543 results on '"Quan Zhou"'
Search Results
2. Research on the Combustion Performance of Municipal Solid Waste in Different Sorting Scenarios: Thermokinetics Investigation via TG–DSC–FTIR–MS
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Bingshuo Li, Wenkuo Zhang, Fan Jia, Tianhua Yang, Suping Bai, and Quan Zhou
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Chemistry ,QD1-999 - Published
- 2023
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3. Optimization Research of Heterogeneous 2D-Parallel Lattice Boltzmann Method Based on Deep Computing Unit
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Shunan Tao, Qiang Li, Quan Zhou, Zhaobing Han, and Lu Lu
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lattice Boltzmann method ,heterogeneous computing ,parallel optimization ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Currently, research on the lattice Boltzmann method mainly focuses on its numerical simulation and applications, and there is an increasing demand for large-scale simulations in practical scenarios. In response to this situation, this study successfully implemented a large-scale heterogeneous parallel algorithm for the lattice Boltzmann method using OpenMP, MPI, Pthread, and OpenCL parallel technologies on the “Dongfang” supercomputer system. The accuracy and effectiveness of this algorithm were verified through the lid-driven cavity flow simulation. The paper focused on optimizing the algorithm in four aspects: Firstly, non-blocking communication was employed to overlap communication and computation, thereby improving parallel efficiency. Secondly, high-speed shared memory was utilized to enhance memory access performance and reduce latency. Thirdly, a balanced computation between the central processing unit and the accelerator was achieved through proper task partitioning and load-balancing strategies. Lastly, memory access efficiency was improved by adjusting the memory layout. Performance testing demonstrated that the optimized algorithm exhibited improved parallel efficiency and scalability, with computational performance that is 4 times greater than before optimization and 20 times that of a 32-core CPU.
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- 2024
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4. Preparation of Fe3O4@SiO2@N-TiO2 and Its Application for Photocatalytic Degradation of Methyl Orange in Na2SO4 Solution
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Li Sun, Xingyu Ouyang, Zilong Li, Zhigang Yuan, Wenbang Gong, Zhen Chen, Shunqi Mei, Ying Liu, and Quan Zhou
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TiO2 ,N-doped ,photocatalytic degradation ,methyl orange ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this paper, Fe3O4@SiO2@TiO2 and N-doped Fe3O4@SiO2@N-TiO2 photocatalysts with magnetic core-shell structures were prepared using a multi-step synthesis method. The materials were analyzed using various techniques, such as X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), selected-area electron diffraction patterns (SAED), and X-ray photoelectron spectroscopy (XPS). The results indicated that the prepared samples had an anatase structure, and N was successfully doped. Fe3O4@SiO2@TiO2 and Fe3O4@SiO2@N-TiO2 with different amounts of nitrogen doping were used for the study of photocatalytic degradation of methyl orange (MO) in pure MO solution, and in MO and Na2SO4 (MO-Na2SO4) mixed solution, respectively. The average photocatalytic degradation rate of MO in pure MO solution with three different batches each of Fe3O4@SiO2@TiO2 and Fe3O4@SiO2@N-TiO2 (3 mL of NH4OH used for doping) under high-pressure mercury lamp irradiation reached 85.25% ± 2.23% and 95.53% ± 0.53%, respectively. The average photocatalytic degradation rate of MO in the MO-Na2SO4 mixed solution with three different batches each of Fe3O4@SiO2@TiO2 and Fe3O4@SiO2@N-TiO2 (3 mL of NH4OH used for doping) under the same irradiation condition reached 90.46% ± 3.33% and 97.79% ± 2.09%, respectively. The results showed that Na2SO4 can promote photocatalytic degradation of MO. The experiment of recycling photocatalysts showed that there was still a good degradation effect after five cycles. Finally, the first-order kinetic model and the photocatalytic degradation mechanism were investigated.
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- 2024
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5. Vacancy manipulating of molybdenum carbide MXenes to enhance Faraday reaction for high performance lithium-ion batteries
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Xin Guo, Changda Wang, Wenjie Wang, Quan Zhou, Wenjie Xu, Pengjun Zhang, Shiqiang Wei, Yuyang Cao, Kefu Zhu, Zhanfeng Liu, Xiya Yang, Yixiu Wang, Xiaojun Wu, Li Song, Shuangming Chen, and Xiaosong Liu
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ordered vacancies ,mxenes ,x-ray absorption fine structure (xafs) ,lithium-ion storage ,mechanism ,Chemistry ,QD1-999 ,Physics ,QC1-999 - Abstract
"Intrinsic" strategies for manipulating the local electronic structure and coordination environment of defect-regulated materials can optimize electrochemical storage performance. Nevertheless, the structure–activity relationship between defects and charge storage is ambiguous, which may be revealed by constructing highly ordered vacancy structures. Herein, we demonstrate molybdenum carbide MXene nanosheets with customized in-plane chemical ordered vacancies (Mo1.33CTx), by utilizing selective etching strategies. Synchrotron-based X-ray characterizations reveal that Mo atoms in Mo1.33CTx show increased average valence of +4.44 compared with the control Mo2CTx. Benefited from the introduced atomic active sites and high valence of Mo, Mo1.33CTx achieves an outstanding capacity of 603 mAh·g−1 at 0.2 A·g−1, superior to most original MXenes. Li+ storage kinetics analysis and density functional theory (DFT) simulations show that this optimized performance ensues from the more charge compensation during charge–discharge process, which enhances Faraday reaction compared with pure Mo2CTx. This vacancy manipulation provides an efficient way to realize MXene's potential as promising electrodes.
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- 2022
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6. Reversible Data Hiding in Encrypted Images Based on the Mixed Multi-Bit Layer Embedding Strategy
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Rui-Hua Liu and Quan Zhou
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reversible data hiding in encrypted images ,high capacity ,separability ,data transfer safety ,adaptive multi-bit layer embedding strategy ,fixed multi-bit layer embedding strategy ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
With the increasing requirements for the security of medical data, military data, and other data transmission, data hiding technology has gradually developed from only protecting the security of secret data to all transmission data. As a necessary technical means, reversible data hiding in encrypted images (RDH-EIs) provides superior performance in terms of security. To simultaneously improve the effectiveness of RDH-EIs, this work proposes a mixed multi-bit layer embedding strategy in encrypted images. The cover image is processed into two categories: available hidden blocks (AHBs) and unavailable hidden blocks (UHBs) at the sender. Then, all data are embedded in the multi-bit layer of the encrypted pixels in AHBs through two embedding strategies to obtain the transmission image. At the receiver, the user can extract the needed data separably according to different keys to achieve error-free extraction of the secret data and lossless recovery of the cover image. The experimental results show that the proposed scheme has the advantages of superior embedding capacity and high decryption quality over the current state-of-the-art works.
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- 2023
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7. Improving Magnetic Field Response of Eddy Current Magneto-Optical Imaging for Defect Detection in Carbon Fiber Reinforced Polymers
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Jiangshan Ai, Quan Zhou, Xu Zhang, Shengping Li, Bing Long, and Libing Bai
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carbon fiber reinforced polymer ,eddy current ,magneto-optical imaging ,nondestructive testing ,phase imaging ,defect detection ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A large number of carbon fiber reinforced polymers have been applied to aircraft and automobiles, and many nondestructive testing methods have been studied to detect their defects. Eddy current magneto-optical imaging nondestructive testing technology has been widely used in the detection of metal materials such as aircraft skin, but it usually requires a large excitation current and, at present, can only detect metal materials with high conductivity. In order to take full advantage of the innate benefits and efficiency of eddy current magneto-optic imaging and enable it to detect defects in carbon fiber reinforced polymers with weak conductivity, it is necessary to improve the magnetic field response of the eddy current magneto-optic imaging system and explore suitable excitation and detection methods. The scanning eddy current magneto-optical imaging nondestructive testing device built in this study has improved the magnetic field response of the system, and the eddy current magneto-optical phase imaging testing method has been proposed to detect the crack defects of carbon fiber reinforced polymers. The effectiveness of the method has been verified by simulation and experiment.
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- 2023
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8. Preparation and Experimental Study of a Low-Initial-Viscosity Gel Plugging Agent
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Bin Huang, Weisen Zhang, Quan Zhou, Cheng Fu, and Shibo He
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Chemistry ,QD1-999 - Published
- 2020
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9. Facile preparation of Cu(II)-modified nitrogen-rich covalent organic polymer for cross-dehydrogenative ortho-aminomethylation of phenols
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Jun Xie, Min Chen, Lin-Ling Peng, Jia-Qi Wu, Quan Zhou, Cong-Shan Zhou, Bi-Quan Xiong, and Yu Liu
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Covalent organic polymers ,Modification. ,Cross-dehydrogenative ortho-aminomethylation. ,Phenols. ,N,N-dimethylanilines. ,Chemistry ,QD1-999 - Abstract
Cu(II)-modified nitrogen-rich covalent organic polymer (Cu/N-COP-1) was fabricated and employed to catalyze the cross-dehydrogenative ortho-aminomethylation of phenols. The Cu/N-COP-1 catalyst displayed excellent catalytic activity under mild conditions without any ligand. Various substituted phenols and N,N-dimethylanilines were successfully converted to the corresponding products. Moreover, the catalyst can be readily reused for at least five consecutive runs without obvious loss of catalytic activity. This can be attributed to the interaction between the nitrogen-containing group of the covalent organic polymer and Cu species, which makes Cu species steadily immobilized on the surface of polymer.
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- 2021
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10. Microwave Absorption of α-Fe2O3@diatomite Composites
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Chenzhi Zhang, Dashuang Wang, Lichao Dong, Kailin Li, Yifan Zhang, Pingan Yang, Shuang Yi, Xingjian Dai, Changqing Yin, Zhilan Du, Xinfang Zhang, Quan Zhou, Zhiyu Yi, Jinsong Rao, and Yuxin Zhang
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diatomite ,α-Fe2O3 ,microwave absorption ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
A neoteric round sieve diatomite (De) decorated with sea-urchin-like alpha-type iron trioxide (α-Fe2O3) synthetics was prepared by the hydrothermal method and further calcination. The results of the electromagnetic (EM) parameters of α-Fe2O3-decorated De (α-Fe2O3@D) showed that the minimum reflection loss (RLmin) of α-Fe2O3@D could reach −54.2 dB at 11.52 GHz and the matched absorber thickness was 3 mm. The frequency bandwidth corresponding to the microwave RL value below −20 dB was up to 8.24 GHz (9.76–18 GHz). This indicates that α-Fe2O3@D composite can be a lightweight and stable material; because of the low density of De (1.9–2.3 g/cm3), the density of α-Fe2O3@D composite material is lower than that of α-Fe2O3 (5.18 g/cm3). We found that the combination of the magnetic loss of sea-urchin-like α-Fe2O3 and the dielectric loss of De has the most dominant role in electromagnetic wave absorption and loss. We focused on comparing the absorbing properties before and after the formation of sea-urchin-like α-Fe2O3 and explain in detail the effects of the structure and crystal shape of this novel composite on the absorbing properties.
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- 2022
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11. A Current Sharing State Estimation Method of Redundant Switched-Mode Power Supply Based on LSTM Neural Network
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Peng He, Quan Zhou, Libing Bai, Songlin Xie, and Weijing Zhang
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switched mode power supply ,current sharing ,ripple wave ,spectrum signature ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Redundant Switched-mode Power supplies (SMPSs) are commonly used to improve electronic systems’ reliability, and accurate estimation of the current sharing state is significant for evaluating the system’s health. Currently, the current sharing state estimation is mainly realized by using current sensors to detect each branch’s current, and the deployment and maintenance costs are high. In this paper, a method for power supply current sharing state estimation based on LSTM recurrent neural network is proposed. By taking advantage of subtle differences in the inherent spectral characteristics of SMPSs, this method only needs to detect the voltage ripple at the switching frequency of the load terminal to estimate the output current of each power supply branch. The verification experiment on the three-power redundant experimental platform shows that the estimation error is less than 10%. The method has the characteristics of simple structure, non-invasion, convenient deployment and maintenance, so it has high application and promotion value.
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- 2022
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12. Study on Photocatalytic Degradation of Acid Red 73 by Fe3O4@TiO2 Exposed (001) Facets
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Li Sun, Quan Zhou, Jiaheng Mao, Xingyu Ouyang, Zhigang Yuan, Xiaoxiang Song, Wenbang Gong, Shunqi Mei, and Wei Xu
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Fe3O4@TiO2 ,Acid Red 73 ,photocatalytic degradation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Water pollution can be treated through the photocatalytic reaction of TiO2 or TiO2 compounds. A solvothermal method was used to prepare Fe3O4 and Fe3O4@TiO2 composite photocatalyst with (001) high-energy facets exposed in the anatase phase. TiO2 and Fe3O4@TiO2 were characterized by field emission scanning electron microscopy, ultraviolet–visible diffuse reflectance spectroscopy, X-ray diffraction spectroscopy and Raman spectroscopy. It was found that the composite Fe3O4@TiO2 can reduce the band gap and maintain a certain proportion of (001) high-energy facet exposure. The band gaps of Fe3O4@TiO2 and TiO2 are 2.5 eV and 2.9 eV, respectively. The exposure percentages of (001) facets of Fe3O4@TiO2 and TiO2 are about 25.2% and 12.1%, respectively. Fe3O4@TiO2 was used for photocatalytic degradation of Acid Red 73, and it was found that Fe3O4@TiO2 could improve the efficiency of photocatalytic degradation of Acid Red 73. The photocatalytic degradation rates of Fe3O4@TiO2 and TiO2 at 24 min were 93.56% and 74.47%, respectively. The cycle experiment of photocatalytic degradation of Acid Red 73 by Fe3O4@TiO2 showed that at the fifth cycle, the rate of dye degradation decreased to 77.05%, but the rate of dye degradation can reach more than 90% after self-cleaning treatment. The photocatalytic degradation mechanism is explained by the energy band theory and the first-order kinetic equation model.
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- 2022
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13. Properties and Mechanisms of Flavin-Dependent Monooxygenases and Their Applications in Natural Product Synthesis
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Yaming Deng, Quan Zhou, Yuzhou Wu, Xi Chen, and Fangrui Zhong
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natural products ,flavin monooxygenases (FMOs) ,flavin-C4a-(hydrogen) peroxide ,flavin-N5-oxide ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Natural products are usually highly complicated organic molecules with special scaffolds, and they are an important resource in medicine. Natural products with complicated structures are produced by enzymes, and this is still a challenging research field, its mechanisms requiring detailed methods for elucidation. Flavin adenine dinucleotide (FAD)-dependent monooxygenases (FMOs) catalyze many oxidation reactions with chemo-, regio-, and stereo-selectivity, and they are involved in the synthesis of many natural products. In this review, we introduce the mechanisms for different FMOs, with the classical FAD (C4a)-hydroperoxide as the major oxidant. We also summarize the difference between FMOs and cytochrome P450 (CYP450) monooxygenases emphasizing the advantages of FMOs and their specificity for substrates. Finally, we present examples of FMO-catalyzed synthesis of natural products. Based on these explanations, this review will expand our knowledge of FMOs as powerful enzymes, as well as implementation of the FMOs as effective tools for biosynthesis.
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- 2022
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14. An Evolutionary Analysis of B-Box Transcription Factors in Strawberry Reveals the Role of FaBBx28c1 in the Regulation of Flowering Time
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Yuntian Ye, Yongqiang Liu, Xiaolong Li, Guangyi Wang, Quan Zhou, Qing Chen, Jiale Li, Xiaorong Wang, and Haoru Tang
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strawberry ,B-box protein ,gene family ,flowering time ,gene expression profiling ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Flowering connects vegetative and generative developmental phases and plays a significant role in strawberry production. The mechanisms that regulate strawberry flowering time are unclear. B-box transcription factors (BBXs) play important roles in the flowering time regulation of plants. Nevertheless, BBXs in octoploid cultivated strawberry (Fragaria ananassa) and their functions in flowering time regulation have not been identified. Here, we identified 51 FaBBXs from cultivated strawberry and 16 FvBBXs from diploid wild strawberry (Fragaria vesca), which were classified into five groups according to phylogenetic analysis. Further evolutionary analysis showed that whole-genome duplication or segmental duplication is a crucial factor that leads to the expansion of the BBX gene family in two strawberry species. Moreover, some loss and acquisition events of FaBBX genes were identified in the genome of cultivated strawberry that could have affected traits of agronomic interest, such as fruit quality. The promoters of FaBBX genes showed an enrichment in light-responsive, cis-regulatory elements, with 16 of these genes showing changes in their transcriptional activity in response to blue light treatment. On the other hand, FaBBX28c1, whose transcriptional activity is reduced in response to blue light, showed a delay in flowering time in Arabidopsis transgenic lines, suggesting its role in the regulation of flowering time in cultivated strawberry. Our results provide new evolutionary insight into the BBX gene family in cultivated strawberry and clues regarding their function in flowering time regulation in plants.
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- 2021
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15. A Fall Posture Classification and Recognition Method Based on Wavelet Packet Transform and Support Vector Machine
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Qingyun Zhang, Jin Tao, Qinglin Sun, Xianyi Zeng, Matthias Dehmer, and Quan Zhou
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falling posture ,classification ,recognition ,wavelet packet transform ,support vector machine ,random forest ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
An accidental fall seriously threatens the health and safety of the elderly. The injuries caused by a fall have a lot to do with the different postures during the fall. Therefore, recognizing the posture of falling is essential for the rescue and care of the elderly. In this paper, a novel method was proposed to improve the classification and recognition accuracy of fall postures. Firstly, the wavelet packet transform was used to extract multiple features from sample data. Secondly, random forest was used to evaluate the importance of the extracted features and obtain effective features through screening. Finally, the support vector machine classifier based on the linear kernel function was used to realize the falling posture recognition. The experiment results on “Simulated Falls and Daily Living Activities Data Set” show that the proposed method can distinguish different types of fall postures and achieve 99% classification accuracy.
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- 2021
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16. Suppression Effect and Mechanism of Amine-Containing MQ Silicone Resin on the Tracking and Erosion Resistance of Silicone Rubber
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Yajun Zhang, Xingrong Zeng, Xuejun Lai, Hongqiang Li, Quan Zhou, and Xiaoyi Huang
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Chemistry ,QD1-999 - Published
- 2017
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17. Solid-Phase Preparation of Al-TiO2 for Efficient Separation of Bioderived Product Danshensu
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Fei Chang, Zhong Bing He, and Quan Zhou
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Chemistry ,QD1-999 - Abstract
Four kinds of Al-TiO2 solid samples with different Ti/Al ratios of 1 : 0.1, 1 : 0.09, 1 : 0.07, and 1 : 0.05 were synthesized via a solid-phase synthesis method and characterized by XRD, SEM, EDS, BET, and other techniques. The prepared solids were used for separation of the bioderived product danshensu, the content of which was determined by UV spectrophotometry. Moreover, the effects of extract concentration, PH value, adsorption time, and ethanol elution volume were investigated. The results showed that these Al-TiO2 samples had good adsorption and desorption ability. Especially, the solid Al-TiO2 with a Ti/Al ratio of 1 : 0.05 is more suitable for the separation of danshensu, exhibiting a higher adsorption (77.70%) under 2 h adsorption time and pH = 3; meanwhile, the high desorption rate (70.29%)was received under 80% ethanol and the sample concentration of 3.0 mg/mL.
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- 2019
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18. In-flight Wind Field Identification and Prediction of Parafoil Systems
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Haitao Gao, Jin Tao, Matthias Dehmer, Frank Emmert-Streib, Qinglin Sun, Zengqiang Chen, Guangming Xie, and Quan Zhou
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wind field ,identification ,prediction ,parafoil system ,autonomous homing ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The wind field is an essential factor that affects accurate homing and flare landing of parafoil systems. In order to obtain the ambient wind field during the descent of a parafoil system, a combination method of in-flight wind field identification and prediction is proposed. First, a wind identification method only using global position system information is derived based on the flight dynamics of parafoil systems. Then a wind field prediction model is constructed using the atmospheric dynamics, and the low-altitude wind field is predicted based on the identified wind field of high-altitude. Finally, simulations of wind field identification and prediction are conducted. The results demonstrate that the proposed method can identify the wind fields precisely and also predict the wind fields reasonably. This method can potentially be applied in practical parafoil systems to provide wind field information for homing tasks.
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- 2020
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19. The Preparation and Properties of Multilayer Cu-MTa2O5 Composite Coatings on Ti6Al4V for Biomedical Applications
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Zeliang Ding, Yi Wang, Quan Zhou, Ziyu Ding, Yiyong Wu, Yuefang Zhu, Wensong Shi, and Quanguo He
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copper ,ta2o5 ,ceramic coating ,ti6al4v ,magnetron sputtering ,Chemistry ,QD1-999 - Abstract
For the enhancement of the anticorrosion and antibacterial performance of the biomedical alloy Ti6Al4V, a novel Cu incorporated multilayer Ta2O5ceramic composite coating Cu-Ta2O5/Ta2O5/Ta2O5-TiO2/TiO2/Ti (coating codeCu-MTa2O5) was developed by radio frequency (RF) and direct current (DC) reactive magnetron sputtering. Meanwhile, to better display the multilayer Ta2O5 coating mentioned above, a monolayer Ta2O5 ceramic coating was deposited onto the surface of Ti6Al4V alloy as a reference. The surface morphology, microstructure, phase constituents, and elemental states of the coating were evaluated by atomic force microscopy, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy, respectively. The adhesion strength, wettability, anticorrosion and antibacterial properties of the coating were examined by a scratch tester, contact angle measurement, electrochemical workstations, and plate counting method, respectively. The results showed that the deposited coatings were amorphous and hydrophobic. Cu doped into the Ta2O5 coating existed as CuO and Cu2O. A Ta2O5-TiO2/TiO2/Ti multi-interlayer massively enhanced the adhesion strength of the coating, which was 2.9 times stronger than that of the monolayer Ta2O5coating. The multilayer Cu-MTa2O5 coating revealed a higher corrosion potential and smaller corrosion current density as compared to the uncoated Ti6Al4V, indicating the better anticorrosion performance of Ti6Al4V. Moreover, a 99.8% antibacterial effect of Cu-MTa2O5 coated against Staphylococcus aureuswas obtained.
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- 2019
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20. Formation of Nanospikes on AISI 420 Martensitic Stainless Steel under Gallium Ion Bombardment
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Zoran Cenev, Malte Bartenwerfer, Waldemar Klauser, Ville Jokinen, Sergej Fatikow, and Quan Zhou
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focused ion beam ,nanospikes ,martensite ,stainless steel ,gallium ,bombardment ,irradiation effects ,sharp needle ,incident angle ,Chemistry ,QD1-999 - Abstract
The focused ion beam (FIB) has proven to be an extremely powerful tool for the nanometer-scale machining and patterning of nanostructures. In this work, we experimentally study the behavior of AISI 420 martensitic stainless steel when bombarded by Ga+ ions in a FIB system. The results show the formation of nanometer sized spiky structures. Utilizing the nanospiking effect, we fabricated a single-tip needle with a measured 15.15 nanometer curvature radius and a microneedle with a nanometer sized spiky surface. The nanospikes can be made straight or angled, depending on the incident angle between the sample and the beam. We also show that the nanospiking effect is present in ferritic AISI 430 stainless steel. The weak occurrence of the nanospiking effect in between nano-rough regions (nano-cliffs) was also witnessed for austenitic AISI 316 and martensitic AISI 431 stainless steel samples.
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- 2019
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21. UMP Kinase Regulates Chloroplast Development and Cold Response in Rice
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Qing Dong, Ying-Xin Zhang, Quan Zhou, Qun-En Liu, Dai-Bo Chen, Hong Wang, Shi-Hua Cheng, Li-Yong Cao, and Xi-Hong Shen
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UMP kinase ,chloroplast development ,abiotic stress response ,rice ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Pyrimidine nucleotides are important metabolites that are building blocks of nucleic acids, which participate in various aspects of plant development. Only a few genes involved in pyrimidine metabolism have been identified in rice and the majority of their functions remain unclear. In this study, we used a map-based cloning strategy to isolate a UMPK gene in rice, encoding the UMP kinase that phosphorylates UMP to form UDP, from a recessive mutant with pale-green leaves. In the mutant, UDP content always decreased, while UTP content fluctuated with the development of leaves. Mutation of UMPK reduced chlorophyll contents and decreased photosynthetic capacity. In the mutant, transcription of plastid-encoded RNA polymerase-dependent genes, including psaA, psbB, psbC and petB, was significantly reduced, whereas transcription of nuclear-encoded RNA polymerase-dependent genes, including rpoA, rpoB, rpoC1, and rpl23, was elevated. The expression of UMPK was significantly induced by various stresses, including cold, heat, and drought. Increased sensitivity to cold stress was observed in the mutant, based on the survival rate and malondialdehyde content. High accumulation of hydrogen peroxide was found in the mutant, which was enhanced by cold treatment. Our results indicate that the UMP kinase gene plays important roles in regulating chloroplast development and stress response in rice.
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- 2019
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22. Sub-Pixel Chessboard Corner Localization for Camera Calibration and Pose Estimation
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Tianlong Yang, Qiancheng Zhao, Xian Wang, and Quan Zhou
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chessboard corner ,camera calibration ,pose estimation ,sub-pixel localization ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This work describes a novel approach to localize sub-pixel chessboard corners for camera calibration and pose estimation. An ideally continuous chessboard corner model is established, as a function of corner coordinates, rotation and shear angles, gain and offset of grayscale, and blurring strength. The ideal model is evaluated by a low-cost and high-similarity approximation for sub-pixel localization, and by performing a nonlinear fit to input image. A self-checking technique is also proposed by investigating qualities of the model fits, for ensuring the reliability of addressing perspective-n-point problem. The proposed method is verified by experiments, and results show that it can share a high performance. It is also implemented and examined in a common vision system, which demonstrates that it is suitable for on-site use.
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- 2018
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23. Transcytosis-inducing biomaterials for actively translocating nanomedicines
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Shiqun Shao, Lei Xu, Quan Zhou, and Youqing Shen
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Transcytosis ,Chemistry ,Cell biology - Published
- 2023
24. In Vivo Evaluation of Near-Infrared Fluorescent Probe for TIM3 Targeting in Mouse Glioma
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Gordon Li, Carmel T. Chan, Heike E. Daldrup-Link, Chinghsin Huang, Sanjiv S. Gambhir, Quan Zhou, Michael Zhang, Wei Wu, and Michael Lim
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Cancer Research ,T cell ,medicine.medical_treatment ,Article ,Flow cytometry ,Mice ,Immune system ,In vivo ,Cell Line, Tumor ,Glioma ,Tumor Microenvironment ,medicine ,Animals ,Humans ,Radiology, Nuclear Medicine and imaging ,Hepatitis A Virus Cellular Receptor 2 ,Fluorescent Dyes ,Tumor microenvironment ,medicine.diagnostic_test ,Chemistry ,Immunotherapy ,medicine.disease ,Isotype ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Oncology ,Cancer research ,Glioblastoma - Abstract
PURPOSE: Current checkpoint inhibitor immunotherapy strategies in glioblastoma are challenged by mechanisms of resistance including an immunosuppressive tumor microenvironment. T cell immunoglobulin domain and mucin domain 3 (TIM3) is a late phase checkpoint receptor traditionally associated with T cell exhaustion. We apply fluorescent imaging techniques to explore feasibility of in vivo visualization of the immune state in a glioblastoma mouse model. PROCEDURES: TIM3 monoclonal antibody was conjugated to a near-infrared fluorescent dye, IRDye-800CW (800CW). The TIM3 experimental conjugate and isotype control were assessed for specificity with immunofluorescent staining and flow cytometry in murine cell lines (GL261 glioma and RAW264.7 macrophages). C57BL/6 mice with orthotopically implanted GL261 cells were imaged in vivo over four days after intravenous TIM3-800CW injection to assess tumor specific uptake. Cell specific uptake was then assessed on histologic sections. RESULTS: The experimental TIM3-800CW, but not its isotype control, bound to RAW264.7 macrophages in vitro. Specificity to RAW264.7 macrophages and not GL261 tumor cells was quantitatively confirmed with the corresponding clone of TIM3 on flow cytometry. In vivo fluorescence imaging of the 800CW signal was localized to the intracranial tumor and significantly higher for the TIM3-800CW cohort, relative to non-targeting isotype control, immediately after tail vein injection and for up to 48 hours after injection. Resected organs of tumor bearing mice showed significantly higher uptake in the liver and spleen. TIM3-800CW was seen to co-stain with CD3 (13%), CD11b (29%), and CD206 (26%). CONCLUSIONS: We propose fluorescent imaging of immune cell imaging as a potential strategy for monitoring and localizing immunologically relevant foci in the setting of brain tumors. Alternative markers and target validation will further clarify the temporal relationship of immunosuppressive effector cells throughout glioma resistance.
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- 2021
25. Photocatalytic Nitroaromatic Prodrug Activation by Functionalized Gold Nanoclusters
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Limei Tian, Ke Hu, Rong Liu, Quan Zhou, Dajiao Cheng, Yinghong Yue, and Fushuang Niu
- Subjects
Chemistry ,medicine.medical_treatment ,Cancer cell ,Photocatalysis ,medicine ,General Materials Science ,Photosensitizer ,Photodynamic therapy ,Prodrug ,Combinatorial chemistry ,Nanoclusters - Abstract
Photocatalytic activation of prodrugs for killing cancer cells is an attractive alternative phototherapy to photodynamic therapy that typically relies on the supply of oxygen. Although prodrugs are...
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- 2021
26. Precise in-situ release of microRNA from an injectable hydrogel induces bone regeneration
- Author
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Jiali Zhao, Quan Xiao, Cenhao Wu, Quan Zhou, Jun Ge, Minfeng Gan, Yingjie Wang, Qi Yan, Hao Yu, Huilin Yang, Wenxin Wang, and Jun Zou
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Bone Regeneration ,technology, industry, and agriculture ,Biomedical Engineering ,Cell Differentiation ,Hydrogels ,General Medicine ,Polyethylene glycol ,Biochemistry ,Controlled release ,Rats ,Biomaterials ,MicroRNAs ,chemistry.chemical_compound ,chemistry ,Tissue engineering ,Osteogenesis ,In vivo ,PEG ratio ,Click chemistry ,Biophysics ,Animals ,Bone regeneration ,Molecular Biology ,Ethylene glycol ,Biotechnology - Abstract
Critical bone defects are a common yet challenging orthopedic problem. Tissue engineering is an emerging and promising strategy for bone regeneration in large-scale bone defects. The precise on-demand release of osteogenic factors is critical for controlling the osteogenic differentiation of seed cells with the support of appropriate three dimensional scaffolds. However, most of the effective osteogenic factors are biomacromolecules with release behaviors that are difficult to control. Here, the cholesterol-modified non-coding microRNA Chol-miR-26a was used to promote the osteogenic differentiation of human mesenchymal stem cells (hMSCs). Chol-miR-26a was conjugated to an injectable poly(ethylene glycol) (PEG) hydrogel through an ultraviolet (UV)-cleavable ester bond. The injectable PEG hydrogel was formed by a copper-free click reaction between the terminal azide groups of 8-armed PEG and dibenzocyclooctyne-biofunctionalized PEG, into which UV-cleavable Chol-miR-26a was simultaneously conjugated via a Michael addition reaction. Upon UV irradiation, Gel-c-miR-26a (MLCaged) released Chol-c-miR-26a selectively and exhibited significantly improved efficacy in bone regeneration compared to the hydrogel without UV irradiation and UV-uncleavable MLControl. MLCaged significantly enhanced alkaline phosphatase activity and promoted calcium nodule deposition in vitro and repaired critical skull defects in a rat animal model, demonstrating that injectable implantation with the precise release of osteogenic factors has the potential to repair large-scale bone defects in clinical practice. Statement of significance Provide a novel and practical strategy via hydrogel for efficient delivery and precisely controlled release of miRNAs into bone defect sites. The hydrogel is formed by polyethylene glycol (PEG), which is crosslinked by ‘click’ reaction. Cholesterol-modified miR-26a loading on the hydrogel is covalently patterned onto the fibers of hydrogel through a UV light-cleavable linker, which prevents undesired release of miRNA. This hydrogel could realize the controlled release of miRNA under light regulation both in vitro and in vivo, thus realize bone regeneration.
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- 2021
27. Enhanced bone regenerative properties of calcium phosphate ceramic granules in rabbit posterolateral spinal fusion through a reduction of grain size
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Linnan Wang, Yonghao Wu, Quan Zhou, Cong Feng, Limin Liu, Xi Yang, Yueming Song, Kai Zhang, Xiangdong Zhu, Xiangfeng Li, Xingdong Zhang, and Yumei Xiao
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Materials science ,QH301-705.5 ,medicine.medical_treatment ,Biomedical Engineering ,chemistry.chemical_element ,Nanotopography ,Calcium ,Apatite ,Article ,Biomaterials ,Osteogenic differentiation ,Osteoinductivity ,Posterolateral spinal fusion ,medicine ,MC3T3 ,Biology (General) ,Bone regeneration ,Materials of engineering and construction. Mechanics of materials ,Microscale chemistry ,Calcium phosphate ceramics ,chemistry ,Spinal fusion ,visual_art ,visual_art.visual_art_medium ,TA401-492 ,Biotechnology ,Biomedical engineering ,Protein adsorption - Abstract
Osteoinductivity is a crucial factor to determine the success and efficiency of posterolateral spinal fusion (PLF) by employing calcium phosphate (Ca-P) bioceramics. In this study, three kinds of Ca-P ceramics with microscale to nanoscale gain size (BCP-control, BCP-micro and BCP-nano) were prepared and their physicochemical properties were characterized. BCP-nano had the spherical shape and nanoscale gain size, BCP-micro had the spherical shape and microscale gain size, and BCP-control (BAM®) had the irregular shape and microscale gain size. The obtained BCP-nano with specific nanotopography could well regulate in vitro protein adsorption and osteogenic differentiation of MC3T3 cells. In vivo rabbit PLF procedures further confirmed that nanotopography of BCP-nano might be responsible for the stronger bone regenerative ability comparing with BCP-micro and BCP-control. Collectedly, due to nanocrystal similarity with natural bone apatite, BCP-nano has excellent efficacy in guiding bone regeneration of PLF, and holds great potentials to become an alternative to standard bone grafts for future clinical applications., Graphical abstract Image 1, Highlights • The nanocrystal of porous BCP ceramic spheres is similar to natural bone apatite. • BCP nanoceramics is conducive to protein adsorption and osteogenic differentiation of MC3T3 cells. • Osteoindutivity of BCP ceramics is a crucial factor to determine the sucess and efficiency of PLF. • BCP ceramic spheres with nanotopography hold great potential in clinical PLF applications.
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- 2021
28. Ruthenium-based PACT agents based on bisquinoline chelates: synthesis, photochemistry, and cytotoxicity
- Author
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Sylvestre Bonnet, Anja Busemann, Ingo Ott, Ingrid Flaspohler, Vincent H. S. van Rixel, Sina K Goetzfried, Xue-Quan Zhou, Maxime A. Siegler, and Claudia Schmidt
- Subjects
Models, Molecular ,Original Paper ,Molecular Structure ,Cell Survival ,Ligand ,Singlet oxygen ,Quantum yield ,chemistry.chemical_element ,Antineoplastic Agents ,Photochemistry ,Biochemistry ,Ruthenium ,Inorganic Chemistry ,chemistry.chemical_compound ,Thioether ,chemistry ,Cell Line, Tumor ,Lipophilicity ,Humans ,Ruthenium Compounds ,Chelation ,Amine gas treating - Abstract
The known ruthenium complex [Ru(tpy)(bpy)(Hmte)](PF6)2 ([1](PF6)2, where tpy = 2,2’:6’,2″-terpyridine, bpy = 2,2’-bipyridine, Hmte = 2-(methylthio)ethanol) is photosubstitutionally active but non-toxic to cancer cells even upon light irradiation. In this work, the two analogs complexes [Ru(tpy)(NN)(Hmte)](PF6)2, where NN = 3,3'-biisoquinoline (i-biq, [2](PF6)2) and di(isoquinolin-3-yl)amine (i-Hdiqa, [3](PF6)2), were synthesized and their photochemistry and phototoxicity evaluated to assess their suitability as photoactivated chemotherapy (PACT) agents. The increase of the aromatic surface of [2](PF6)2 and [3](PF6)2, compared to [1](PF6)2, leads to higher lipophilicity and higher cellular uptake for the former complexes. Such improved uptake is directly correlated to the cytotoxicity of these compounds in the dark: while [2](PF6)2 and [3](PF6)2 showed low EC50 values in human cancer cells, [1](PF6)2 is not cytotoxic due to poor cellular uptake. While stable in the dark, all complexes substituted the protecting thioether ligand upon light irradiation (520 nm), with the highest photosubstitution quantum yield found for [3](PF6)2 (Φ[3] = 0.070). Compounds [2](PF6)2 and [3](PF6)2 were found both more cytotoxic after light activation than in the dark, with a photo index of 4. Considering the very low singlet oxygen quantum yields of these compounds, and the lack of cytotoxicity of the photoreleased Hmte thioether ligand, it can be concluded that the toxicity observed after light activation is due to the photoreleased aqua complexes [Ru(tpy)(NN)(OH2)]2+, and thus that [2](PF6)2 and [3](PF6)2 are promising PACT candidates. Graphic abstract
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- 2021
29. Manganese-Pincer-Catalyzed Nitrile Hydration, α-Deuteration, and α-Deuterated Amide Formation via Metal Ligand Cooperation
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Quan-Quan Zhou, Sayan Kar, David Milstein, Yehoshoa Ben-David, You-Quan Zou, and Yael Diskin-Posner
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Letter ,Nitrile ,010405 organic chemistry ,Ligand ,chemistry.chemical_element ,General Chemistry ,Manganese ,010402 general chemistry ,01 natural sciences ,Toluene ,Medicinal chemistry ,Catalysis ,α-deuteration ,0104 chemical sciences ,Pincer movement ,Solvent ,chemistry.chemical_compound ,manganese pincer complex ,chemistry ,metal−ligand cooperation ,Amide ,nitriles ,hydration - Abstract
A simple and efficient system for the hydration and α-deuteration of nitriles to form amides, α-deuterated nitriles, and α-deuterated amides catalyzed by a single pincer complex of the earth-abundant manganese capable of metal-ligand cooperation is reported. The reaction is selective and tolerates a wide range of functional groups, giving the corresponding amides in moderate to good yields. Changing the solvent from tert-butanol to toluene and using D2O results in formation of α-deuterated nitriles in high selectivity. Moreover, α-deuterated amides can be obtained in one step directly from nitriles and D2O in THF. Preliminary mechanistic studies suggest the transformations contributing toward activation of the nitriles via a metal-ligand cooperative pathway, generating the manganese ketimido and enamido pincer complexes as the key intermediates for further transformations.
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- 2021
30. Effectiveness of chelating agent–assisted Fenton-like processes on remediation of glucocorticoid-contaminated soil using chemical and biological assessment: performance comparison of CaO2 and H2O2
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Quan Zhou, Gao Xiaoting, Zhan Jiaxun, Jie Wang, Yanan Liu, Ai Zhang, Li Zhenyu, and Andere Clement Miruka
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Chemistry ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Microorganism ,General Medicine ,Contamination ,Pollution ,Soil contamination ,chemistry.chemical_compound ,Environmental chemistry ,Soil water ,Environmental Chemistry ,Ecotoxicology ,Chelation ,Citric acid - Abstract
Glucocorticoids (GCs) have drawn great concern due to widespread contamination in the environment and application in treating COVID-19. Most studies on GC removal mainly focused on aquatic environment, while GC behaviors in soil were less mentioned. In this study, degradation of three selected GCs in soil has been investigated using citric acid (CA)-modified Fenton-like processes (H2O2/Fe(III)/CA and CaO2/Fe(III)/CA treatments). The results showed that GCs in soil can be removed by modified Fenton-like processes (removal efficiency gt; 70% for 24 h). CaO2/Fe(III)/CA was more efficient than H2O2/Fe(III)/CA at low oxidant dosage ( 4 h). Besides the chemical assessment with GC removal, effects of Fenton-like processes were also evaluated by biological assessments with bacteria and plants. CaO2/Fe(III)/CA was less harmful to the richness and diversity of microorganisms in soil compared to H2O2/Fe(III)/CA. Weaker phytotoxic effects were observed on GC-contaminated soil treated by CaO2/Fe(III)/CA than H2O2/Fe(III)/CA. This study, therefore, recommends CaO2-based treatments to remediate GC-contaminated soils.
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- 2021
31. The distinctive responses of hyperthermophilic, thermophilic and mesophilic anaerobic digesters to restaurant-discharged oily waste
- Author
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Xiao-Xiao Li, Fan Yang, Li-Jie Wu, Quan Zhou, Yong-Kang Lyu, and Rui-Peng Ren
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Food waste ,Anaerobic digestion ,Digestion (alchemy) ,Grease trap ,Chemistry ,Thermophile ,Bioengineering ,Food science ,Long chain fatty acid ,Applied Microbiology and Biotechnology ,Biochemistry ,Anaerobic exercise ,Mesophile - Abstract
De-oiled grease trap waste (GTW) has been proven appropriate for anaerobic digestion treatment. Continuous hyperthermophilic at 70 ℃, thermophilic and mesophilic digestion were operated in parallel to investigate the distinctive responses to the de-oiled GTW. Mesophilic digestion achieved higher tolerance loading than the others. Biogas production was detected in the recovery period for the inhibited hyperthermophilic digester, and the recovery time lasted approximately 10 days longer than the thermophilic one. The long chain fatty acid (LCFA) concentrations at the starting points of recovery were determined to be 5.6 mmol L−1 and 6.2 mmol L−1 for the hyperthermophilic and thermophilic digestion, respectively. Under the similar lipid loading, food waste with composite fractions was observed favorable for biogas production in the hyperthermophilic digester. Residual lipid concentration remained higher for the hyperthermophilic digestion, about twice more than the others. Furthermore, composite substrate alleviated the inhibition from LCFAs, for the dominant was converted to the ones with shorter chain length.
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- 2021
32. Can hydrogen enriched biogas be used as domestic fuel? - Part II: Pollutants Emission from Combustion of Biogas/H2/air Fuel Mixture
- Author
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Quan Zhou, Yi Chen, Chun Wah Leung, and Udaya Kahangamage
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Pollutant ,Waste management ,Hydrogen ,chemistry ,Biogas ,General Engineering ,Environmental science ,chemistry.chemical_element ,Combustion - Abstract
Biogas is considered a sustainable source of energy which is largely untapped owing to its inherent weaknesses such as low thermal performance and potentially harmful emissions. Its thermal performance and emission characteristics can be enhanced through the technique of enriching with higher grade fuel. In this research study, biogas enriched with hydrogen was tested for its emission characteristics. A synthetic biogas identified as BG60 (60% CH4 and 40% CO2) enriched with 20% hydrogen (80%BG60-20%H2) was used for the test. Experiments were carried out for combustion of the enriched gas for a wide range of Reynolds numbers and equivalence ratios. The results indicate that the enriched fuel emits less CO and NOx than commonly used domestic fuel LPG. It also has a better thermal and emission performance than BG60. The low pollutant emissions compared with LPG, use of renewable feedstock for biogas production, and competitive cost may make the blended 80%BG60-20%H2 an attractive sustainable alternative domestic fuel choice for environmentally conscious urban dwellers of modern cities.
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- 2021
33. Can hydrogen enriched biogas be used as domestic fuel? - Part I – Thermal Characteristics of Blended Biogas/H2 Impinging Flames
- Author
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Chun Wah Leung, Quan Zhou, Yi Chen, and Udaya Kahangamage
- Subjects
Waste management ,Hydrogen ,chemistry ,Biogas ,Thermal ,General Engineering ,Environmental science ,chemistry.chemical_element - Abstract
Biogas is a renewable energy source widely produced by breakdowns of organic matters in natural environment and industry. However, it is not yet an ideal replacement of fossil fuels because its high CO2 content would deteriorate its thermal performance. To upgrade biogas for possible domestic application, hydrogen enrichment is proposed by adding high-grade hydrogen (H2) to biogas in order to improve its flammability and heating value, and reduce pollutant emission. However, most previous studies on blended Biogas/H2 focus on analysing the effects of H2 fraction and nozzle-to-plate distance on the heat flux profile and flame temperature. No comprehensive study has ever demonstrated the influence of the Reynolds number and equivalence ratio under a wide operating range. In this study, a test rig was built to investigate the effects of the Reynolds number and equivalence ratio on heat flux and thermal efficiency of blended biogas/H2 impinging flame. The blended biogas/H2 consisted of 80% biogas and 20% H2 addition in volume. Biogas was artificially made by 60% CH4 and 40% CO2 (BG60). The Reynolds number ranges from 300 to 1500 and equivalence ratio ranges from 1 to 3. A comparative study was also conducted between pure biogas (BG60) and biogas with 20% H2 enrichment.
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- 2021
34. Effect of Thermal Aging on Threshold Field Strength and Relative Permittivity of Cross-Linked Polyethylene with Different Cross-Linking Agent Contents
- Author
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Miao Zhao, Quan Zhou, Qi Fei, Hengyi Zhou, Duan Xujin, and Dai Wan
- Subjects
Low-density polyethylene ,chemistry.chemical_compound ,Cross-linked polyethylene ,Materials science ,chemistry ,Relative permittivity ,Thermal aging ,Field strength ,Electrical and Electronic Engineering ,Composite material ,Polyethylene ,Dissipation ,Space charge - Abstract
This article presents the effect of thermal aging on threshold field strength and relative permittivity of cross-linked polyethylene (XLPE) with different cross-linking agent contents. Here, low-density polyethylene (LDPE) and dicumyl peroxide (DCP) are used as basic experimental material and cross-linking agent, respectively. Eventually, experimental results indicate that thermal aging can gradually make threshold field strength and relative permittivity of XLPE with different DCP contents increase and decrease, respectively. Besides, threshold field strength of XLPE with different DCP contents increases first and then decreases as the increase of DCP content, while relative permittivity of XLPE with different DCP contents decreases first and then increases as DCP content increases at different thermal aging time, etc. These studies in this article are the basis of the research on space charge accumulation and dissipation inside XLPE materials, which are of great significance to the normal operation of XLPE cables.
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- 2021
35. Simultaneous determination of carbofuran and 3-hydroxycarbofuran in duck liver by an UPLC-MS/MS
- Author
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Quan Zhou, Xianqin Wang, Yang Yu, Jianshe Ma, Siyuan Chen, and Congcong Wen
- Subjects
chemistry.chemical_compound ,Chromatography ,chemistry ,Uplc ms ms ,General Chemistry ,3-hydroxycarbofuran ,Carbofuran - Abstract
Carbofuran is a carbamate pesticide, a broad-spectrum, high-efficiency, low-residue, and highly toxic insecticide, acaricide, and nematicide, widely used in agriculture. Carbofuran is most harmful to birds, and birds or insects killed by furan poisoning can be killed by secondary poisoning after being foraged by raptors, small mammals, or reptiles. In this paper, an UPLC-MS/MS method was developed for the determination of carbofuran and its metabolite, 3-hydroxycarbofuran, in duck liver. Liver tissue was first ground into a homogenate and then passed through ethyl acetate liquid-liquid extraction processing samples. Multiple reaction monitoring (MRM) mode was used for quantitative analysis, m/z 222.1 → 165.1 for carbofuran, m/z 238.1 → 180.9 for 3-hydroxycarbofuran and m/z 290.2 → 198.2 for an internal standard. The standard curves of carbofuran and 3-hydroxycarbofuran in duck liver were within a range of 2–2000 ng/g, where the linearity was good, the lower limit of quantification was 2 ng/g. The intra-day precision of carbofuran and 3-hydroxycarbofuran was
- Published
- 2021
36. Enhanced Peroxidase‐mimicking Activity of Plasmonic Gold‐modified Mn 3 O 4 Nanocomposites through Photoexcited Hot Electron Transfer
- Author
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Ke Hu, Wei Feng, Xiaoxuan Han, Hui Zhang, Quan Zhou, and Rong Liu
- Subjects
Nanocomposite ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,General Chemistry ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Nanomaterials ,Electron transfer ,Catalytic oxidation ,Absorption band ,Colloidal gold ,Biosensor ,Plasmon - Abstract
Enzyme-mimicking artificial nanomaterials often termed nanozymes have broad applications in many fields, including biosensing, pollutant degradation and cancer diagnosis. Herein, we introduce a plasmonic gold nanoparticle-modified Mn3 O4 nanozyme (Mn3 O4 -Au). Visible or near infrared light excitation into the plasmonic absorption band of the surface-bound gold nanoparticles enhances the catalytic oxidation of tetramethylbenzidine (TMB). The mechanism of light-enhanced peroxidase activity is proposed based on the Mn3 O4 conduction band mediated hot electron transfer from photoexcited gold nanoparticles to H2 O2 which undergoes further oxygen-oxygen bond cleavage to yield hydroxyl radical. The surface decoration of plasmonic gold nanoparticles endows Mn3 O4 -Au to be a light-regulated nanozyme.
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- 2021
37. Inhibitor of DNA-binding family regulates the prognosis of ovarian cancer
- Author
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Ye-Dong Mei, Huai-Jie Yang, Quan Zhou, and Ya-ling Tao
- Subjects
0301 basic medicine ,Cancer Research ,Normal tissue ,Datasets as Topic ,Down-Regulation ,Kaplan-Meier Estimate ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Text mining ,Databases, Genetic ,Biomarkers, Tumor ,Humans ,Mutational status ,Medicine ,In patient ,RNA, Messenger ,Pathological ,Neoplasm Staging ,Ovarian Neoplasms ,Messenger RNA ,business.industry ,Gene Expression Profiling ,Ovary ,General Medicine ,Prognosis ,medicine.disease ,Progression-Free Survival ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Mutation ,Cancer research ,Female ,Inhibitor of Differentiation Proteins ,Tumor Suppressor Protein p53 ,business ,Ovarian cancer ,DNA - Abstract
Aim: The mechanistic role of inhibitor of DNA binding or differentiation (ID) family in ovarian cancer (OC) has remained unclear. Materials & methods: We used the Oncomine, GEPIA, Kaplan–Meier Plotter, cBioPortal, SurvExpress, PROGgene V2, TIMER, and FunRich to evaluate the prognostic value of IDs in patients with OC. Results: the mRNA transcripts of all IDs were markedly downregulated in OC compared with normal tissue. The prognostic value of IDs was also explored within the subtypes, pathological stages, clinical stages and TP53 mutational status. The group with low-risk IDs showed relatively good overall survival (OS) compared with the high-risk group. Conclusion: ID1/3/4 may be exploited as promising prognostic biomarkers and therapeutic targets in OC patients.
- Published
- 2021
38. Towards the understanding of hyperthermophilic methanogenesis from waste activated sludge at 70 °C: Performance, stability, kinetic and microbial community analyses
- Author
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Yong-Kang Lyu, Quan Zhou, Fan Yang, Rui-Peng Ren, Xiao-Xiao Li, and Li-Jie Wu
- Subjects
Sewage ,biology ,Methanogenesis ,Chemistry ,Microbiota ,020209 energy ,Methanospirillum ,02 engineering and technology ,010501 environmental sciences ,Methanothermobacter ,Pulp and paper industry ,biology.organism_classification ,01 natural sciences ,Kinetics ,Hydrolysis ,Anaerobic digestion ,Bioreactors ,Activated sludge ,0202 electrical engineering, electronic engineering, information engineering ,Degradation (geology) ,Anaerobiosis ,Methane ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Mesophile - Abstract
Anaerobic digestion is promising for waste activated sludge (WAS) degradation. However, conventional processes were generally stuck with limited hydrolysis and poor pathogen destruction. Hyperthermophilic digestion at 70 °C has drawn attention in overcoming those issues at a relatively low energy requirement and operating difficulties. In order to illuminate its operation characteristics, a single-stage hyperthermophilic digester was controlled at 70 °C and operated continuously to degrade WAS. 88.7 mL/g VSadded of methane yield could be achieved in the hyperthermophilic system, fourfold higher than that in the mesophilic system. Kinetic analysis revealed that hyperthermophilic digestion was advantageous in converting the non-degradable fraction. Consequently, hydrolysis under the hyperthermophilic condition was able to be significantly improved. Above 10 d was necessary for the hyperthermophilic system to gain such a high methane production. In the case of stability, the organic loading of higher than 10.2 g VS/L/d resulted in increasing limitation from methanogenesis and accumulation of propionic, butyric and valeric acids. In addition to the dominant acetoclastic genus Methanothrix for methane production in the hyperthermophilic system, two hydrogenotrophic methanogens Methanospirillum and Methanothermobacter reached 18.84% and 8.31%, respectively. The genus Coprothermobacter, affiliated with the phylum Firmicutes, made more contribution to protein hydrolysis in the hyperthermophilic digester.
- Published
- 2021
39. Effects of dacomitinib on the pharmacokinetics of poziotinib in vivo and in vitro
- Author
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Bo Wang, Weiping Ji, Changxiong Wang, Deru Meng, Wang Shuanghu, Shen Jiquan, Dapeng Dai, Quan Zhou, Feifei Chen, and Yunfang Zhou
- Subjects
medicine.drug_class ,Pharmaceutical Science ,RM1-950 ,Pharmacology ,030226 pharmacology & pharmacy ,01 natural sciences ,Tyrosine-kinase inhibitor ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,tyrosine kinase inhibitor ,Pharmacokinetics ,In vivo ,Drug Discovery ,medicine ,drug–drug interaction ,neoplasms ,biology ,ERBB Family ,Cytochrome P450 ,Poziotinib ,General Medicine ,Dacomitinib ,In vitro ,respiratory tract diseases ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,chemistry ,cytochrome p450 ,biology.protein ,Molecular Medicine ,Therapeutics. Pharmacology ,uplc-ms/ms - Abstract
Context Dacomitinib and poziotinib, irreversible ErbB family blockers, are often used for treatment of non-small cell lung cancer (NSCLC) in the clinic. Objective This study investigates the effect of dacomitinib on the pharmacokinetics of poziotinib in rats. Materials and methods Twelve Sprague–Dawley rats were randomly divided into two groups: the test group (20 mg/kg dacomitinib for 14 consecutive days) and the control group (equal amounts of vehicle). Each group was given an oral dose of 10 mg/kg poziotinib 30 min after administration of dacomitinib or vehicle at the end of the 14 day administration. The concentration of poziotinib in plasma was quantified by UPLC-MS/MS. Both in vitro effects of dacomitinib on poziotinib and the mechanism of the observed inhibition were studied in rat liver microsomes and human liver microsomes. Results When orally administered, dacomitinib increased the AUC, Tmax and decreased CL of poziotinib (p
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- 2021
40. Gold Nanoclusters Perform Enzyme-like Photocatalysis for Prodrug Activation
- Author
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Ke Hu, Fushuang Niu, Rong Liu, Dajiao Cheng, and Quan Zhou
- Subjects
chemistry.chemical_classification ,Enzyme ,chemistry ,Photocatalysis ,General Materials Science ,Nanotechnology ,Prodrug ,Nanoclusters ,Nanomaterials - Abstract
Many synthetic nanomaterials known as nanozymes can catalyze biologically relevant molecular transformations just as natural enzyme does. “Photonanozyme” utilizes light as a spatial and temporal co...
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- 2021
41. Homogeneous Reforming of Aqueous Ethylene Glycol to Glycolic Acid and Pure Hydrogen Catalyzed by Pincer‐Ruthenium Complexes Capable of Metal–Ligand Cooperation
- Author
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You-Quan Zou, Michael Rauch, Aviel Anaby, Liat Avram, Yehoshoa Ben-David, Quan Quan Zhou, Linda J. W. Shimon, Moran Feller, Niklas von Wolff, David Milstein, Yael Diskin-Posner, Weizmann Institute of Science [Rehovot, Israël], Laboratoire d'Electrochimie Moléculaire (LEM (UMR_7591)), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), and Department of Chemical Research Support
- Subjects
Green chemistry ,Aqueous solution ,Hydrogen ,010405 organic chemistry ,Organic Chemistry ,technology, industry, and agriculture ,chemistry.chemical_element ,Homogeneous catalysis ,General Chemistry ,010402 general chemistry ,7. Clean energy ,01 natural sciences ,Combinatorial chemistry ,Catalysis ,12. Responsible consumption ,0104 chemical sciences ,Ruthenium ,chemistry.chemical_compound ,chemistry ,[CHIM]Chemical Sciences ,Ethylene glycol ,Glycolic acid - Abstract
International audience; Glycolic acid is a useful and important α-hydroxy acid that has broad applications. Herein, we report the homogeneous ruthenium catalyzed reforming of aqueous ethylene glycol to generate glycolic acid as well as pure hydrogen gas, without concomitant CO2 emission. This approach provides a clean and sustainable direction to glycolic acid and hydrogen, based on inexpensive, readily available and renewable ethylene glycol using 0.5 mol% of catalyst. In-depth mechanistic experimental and computational studies highlight key aspects of the PNNH-ligand framework involved in this transformation.
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- 2021
42. Albumin-binding prodrugs via reversible iminoboronate forming nanoparticles for cancer drug delivery
- Author
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Jianbin Tang, Quan Zhou, Ying Piao, Zhuxian Zhou, Lingqiao Hao, and Youqing Shen
- Subjects
Drug ,media_common.quotation_subject ,Pharmaceutical Science ,Antineoplastic Agents ,02 engineering and technology ,03 medical and health sciences ,chemistry.chemical_compound ,Drug Delivery Systems ,Pharmacokinetics ,In vivo ,Albumins ,Neoplasms ,medicine ,Humans ,Prodrugs ,Bovine serum albumin ,030304 developmental biology ,media_common ,0303 health sciences ,biology ,Chemistry ,Albumin ,Prodrug ,021001 nanoscience & nanotechnology ,Combinatorial chemistry ,biology.protein ,Curcumin ,Nanoparticles ,Camptothecin ,0210 nano-technology ,medicine.drug - Abstract
Albumin-based nanomedicines are important nanoplatforms for cancer drug delivery. The drugs are either physically encapsulated or covalently conjugated to albumin or albumin-based nanosystems. Physical encapsulation is advantageous due to requiring no chemical modification of drug molecules, but many drugs, for instance, camptothecin (CPT) and curcumin (CCM), though very hydrophobic, can't be loaded in or form nanoformulations with albumin. Herein, we demonstrate prodrugs readily binding to proteins via iminoboronates and forming nanoparticles for cancer drug delivery. CPT and CCM were functionalized with 2-acetylphenylboronic acid (2-APBA) to produce prodrugs CPT-SS-APBA and CCM- APBA. The prodrugs bound to bovine serum albumin (BSA) via formation of iminoboronates and the produced BSA/prodrug readily self-assembled into well-defined nanoparticles with high loading efficiency, improved colloidal stability, and much-improved pharmacokinetics. The nanoparticles effectively released drugs in the intracellular acidic environment or the cytosol rich in glutathione (GSH). In vivo, the nanoparticles showed enhanced anticancer efficacy compared with clinically used irinotecan or sorafenib in subcutaneous 4 T1 or HepG2 tumor models. This work demonstrates a versatile protein-binding prodrug platform applicable to protein-based drug formulations and even antibody-drug conjugates.
- Published
- 2021
43. Cu-Catalyzed Oxidative Dual Arylation of Active Alkenes: Preparation of Cyanoarylated Oxindoles through Denitrogenation of 3-Aminoindazoles
- Author
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Zan Chen, Guo-Jun Deng, Jia Liao, Kewen Tang, Liu Yu, Qiao-Lin Wang, Quan Zhou, and Bi-Quan Xiong
- Subjects
chemistry.chemical_classification ,Double bond ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Intramolecular cyclization ,Oxidative phosphorylation ,Alkenes ,010402 general chemistry ,Cleavage (embryo) ,01 natural sciences ,Combinatorial chemistry ,Catalysis ,Oxindoles ,0104 chemical sciences ,Oxidative Stress ,Oxidation-Reduction - Abstract
A novel and mild Cu-catalyzed oxidative dual arylation of carbon-carbon double bonds in acrylamides with 3-aminoindazoles is proposed for the synthesis of cyanoarylated oxindoles. Notably, 3-aminoindazoles are employed as efficient arylating agents via the cleavage of two C-N bonds. This oxidative dual arylation of active alkenes involves a radical process and undergoes a sequence of 3-aminoindazole oxidation, two-C-N-bond cleavage, cyanoaryl radical addition, and intramolecular cyclization.
- Published
- 2021
44. Co-delivery of doxorubicin and SIS3 by folate-targeted polymeric micelles for overcoming tumor multidrug resistance
- Author
-
Shuanghu Wang, Aiping Deng, Ping Zou, Xueying Tan, Quan Zhou, Jinhui Wang, Jingbo Hu, and Peiwu Geng
- Subjects
Abcg2 ,medicine.medical_treatment ,Pharmaceutical Science ,macromolecular substances ,02 engineering and technology ,030226 pharmacology & pharmacy ,Micelle ,03 medical and health sciences ,0302 clinical medicine ,polycyclic compounds ,medicine ,Doxorubicin ,Chemotherapy ,Polymeric micelles ,biology ,Chemistry ,technology, industry, and agriculture ,Transporter ,021001 nanoscience & nanotechnology ,carbohydrates (lipids) ,Multiple drug resistance ,Cancer cell ,biology.protein ,Cancer research ,0210 nano-technology ,medicine.drug - Abstract
Multidrug resistance (MDR) is considered as a critical limiting factor for the successful chemotherapy, which is mainly characterized by the overexpression of ATP-binding cassette (ABC) transporter ABCB1 or ABCG2. In this study, folate-targeted polymeric micellar carrier was successfully constructed to co-delivery of doxorubicin (DOX) and SIS3 (FA/DOX/SIS3 micelles), a specific Smad3 inhibitor which sensitizes ABCB1- and ABCG2-overexpressing cancer cells to chemotherapeutic agents. The ratio of DOX to SIS3 in polymeric micelles was determined based on the anti-tumor activity against resistant breast cells. In addition, FA/DOX/SIS3 micelles exhibited a much longer circulation time in blood and were preferentially accumulated in resistant tumor tissue. Pharmacodynamic studies showed that FA/DOX/SIS3 micelles possessed superior anti-tumor activity than other DOX-based treatments. Overall, FA/DOX/SIS3 micelles are a promising formulation for the synergistic treatment of drug-resistant tumor.
- Published
- 2021
45. Ultrasonic‐triggered Surface Morphological Reconstruction of MoS 2 for Enhanced Ultrasensitive Humidity Sensing
- Author
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Long Zhang, Chao Wang, Jiafan Chen, Hao-Di Wu, Quan Zhou, Shaohui Zhang, Haifeng Zhang, and Ge-Bo Pan
- Subjects
Biomaterials ,chemistry.chemical_compound ,Materials science ,chemistry ,Renewable Energy, Sustainability and the Environment ,Materials Chemistry ,Energy Engineering and Power Technology ,Humidity ,Ultrasonic sensor ,Composite material ,Molybdenum disulfide - Published
- 2021
46. Hydrogen sulfide-activatable prodrug-backboned block copolymer micelles for delivery of chemotherapeutics
- Author
-
Youqing Shen, Jianbin Tang, Jiajia Xiang, Peiwen Xing, Zhuxian Zhou, Shiqun Shao, Quan Zhou, Xin Liu, and Peihong Shen
- Subjects
Polymers and Plastics ,Organic Chemistry ,Bioengineering ,02 engineering and technology ,Prodrug ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,Micelle ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Paclitaxel ,Amphiphile ,Copolymer ,Azide ,0210 nano-technology ,Linker ,Conjugate - Abstract
Amphiphilic block copolymer prodrugs, which can self-assemble into stable core–shell micelles, have been widely used for anticancer drug delivery. However, a major challenge is to design drug-conjugating linkers stable in blood but selectively cleavable inside tumor cells for drug release. Hydrogen sulfide (H2S) is an important gaseous signaling molecule involved in tumor formation, development, and metastasis and is highly upregulated in multiple cancer types. Accordingly, we designed an H2S-sensitive azide-based linker and used it to conjugate paclitaxel (PTX) to a prodrug copolymer (PEG-PAMPTX). The amphiphilic PEG-PAMPTX self-assembled into micelles with a diameter of about 30 nm, stable under normal physiological conditions for long blood circulation. Once in tumors, the intratumoral H2S selectively reduced the azide group into an amino group, triggering self-cyclization to release PTX rapidly. As a result, the micelles showed remarkably enhanced antitumor activity compared to Taxol in a triple-negative breast cancer orthotopic model.
- Published
- 2021
47. Microstructure and properties of monolayer, bilayer and multilayer Ta2O5-based coatings on biomedical Ti-6Al-4V alloy by magnetron sputtering
- Author
-
Wang Yi, Zeliang Ding, Ziyu Ding, Quan Zhou, Tang Yinghong, and Quanguo He
- Subjects
010302 applied physics ,Materials science ,Process Chemistry and Technology ,Alloy ,02 engineering and technology ,engineering.material ,Sputter deposition ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Corrosion ,Amorphous solid ,chemistry.chemical_compound ,Coating ,chemistry ,0103 physical sciences ,Monolayer ,Tantalum pentoxide ,Materials Chemistry ,Ceramics and Composites ,engineering ,Composite material ,0210 nano-technology - Abstract
In recent years, tantalum pentoxide (Ta2O5) ceramic coating has attracted considerable attention in the modification of implants due to its excellent biocompatibility, high corrosion resistance, and good wear resistance. However, the poor adhesion to the substrate degrades its performance and may become a significant obstacle to its clinical application. In the paper, Ta2O5 monolayer, Ta2O5/Ti bilayer, and Ta2O5/Ta2O5-Ti/Ti multilayer coatings were prepared on the Ti-6Al-4V alloy by magnetron sputtering. The microstructure, chemical composition, residual thermal stress, adhesion strength, mechanical properties, tribological behaviors, and corrosion resistance of the coatings were investigated and compared. The results showed that these deposited coatings were composed of an amorphous nano-Ta2O5 phase, and their surfaces were smooth, dense, and homogeneous without any cracks. Ta2O5/Ta2O5-Ti/Ti coatings exhibited lower thermal residual stress than that of the Ta2O5 and Ta2O5/Ti coatings, which could be attributed to the decrease of the coefficient of thermal expansion (CTE) mismatch between the Ta2O5 film and Ti-6Al-4V substrate due to the introduction of the Ta2O5-Ti/Ti double-interlayer. Moreover, Ta2O5/Ta2O5-Ti/Ti coating was significantly superior to Ta2O5 and Ta2O5/Ti coatings in the adhesion strength, mechanical properties, and wear resistance. These Ta2O5-based coatings can provide excellent corrosion protection for Ti-6Al-4V alloy in simulated body fluids (SBF). The Ta2O5 monolayer coating samples showed the best corrosion resistance, mainly due to its thick out-layer Ta2O5 film. These experimental results provide a feasible way to improve the performances of Ta2O5 coating on Ti-6Al-4V alloy.
- Published
- 2021
48. Cobalt induced growth of hollow MOF spheres for high performance supercapacitors
- Author
-
Quan Zhou, Xu Zhang, Da Lei, Anmin Liu, Ning Qu, and Yang Shixuan
- Subjects
Supercapacitor ,Materials science ,chemistry.chemical_element ,Electrochemistry ,Capacitance ,Redox ,Adsorption ,chemistry ,Chemical engineering ,Materials Chemistry ,Density of states ,General Materials Science ,Metal-organic framework ,Cobalt - Abstract
The development of highly-efficient metal organic framework (MOF) based supercapacitors has attracted much attention. In this work, hollow structure Ni/Co-MOFs have been facilely synthesized by using Co ions as structure-directing agents. Various structures of MOFs, such as hollow, yolk–shell and solid spheres, can be easily obtained through adjusting the molar ratio of Ni/Co. The introduction of an appropriate amount of Co ions can induce the formation of hollow spheres, where the hollow structure can offer rich redox reaction sites and provide fast transport pathways. Moreover, adsorption simulations and density of states calculations illustrate that the adsorbability of OH− and the electrochemical activity on the mixed-metallic MOFs are improved after introducing the Co ions, which can promote the reversible redox reaction activity of the electrode materials. The as-obtained hollow Ni/Co-MOF with the optimized amount of Co ions yields a high capacitance of 1498 F g−1 at 1 A g−1, an excellent rate capability of 67% capacitance retention at 30 A g−1 and a good cycling stability of 71% after 3000 cycles at 5 A g−1. This work may provide useful guidance for tuning the structure and electronic properties of MOFs to enhance the electrochemical performance for supercapacitors.
- Published
- 2021
49. The visible-light-induced acylation/cyclization of alkynoates with acyl oximes for the construction of 3-acylcoumarins
- Author
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Yu Liu, Quan Zhou, Fang-Ting Xiong, Kewen Tang, Bi-Quan Xiong, and Pu Chen
- Subjects
Radical ,Organic Chemistry ,Substituent ,Substrate (chemistry) ,Oxime ,Triple bond ,Biochemistry ,Medicinal chemistry ,Acylation ,chemistry.chemical_compound ,chemistry ,Physical and Theoretical Chemistry ,Acetonitrile ,Bond cleavage - Abstract
A nitrogen-centered radical-mediated carbon-carbon bond cleavage strategy is described to synthesize functionalized 3-acylcoumarins. The strategy is enabled by the visible-light-induced acylation/cyclization of alkynoates with various acyl oxime compounds in acetonitrile. The difunctionalization of carbon-carbon triple bonds precedes the generation of iminyl radicals, which is followed by the formation of acyl radicals. The acyl radicals then attack the carbon-carbon triple bonds, followed by 5-exo-trig cyclization and 1,2-ester migration. This strategy has wide substrate adaptability and good substituent tolerance.
- Published
- 2021
50. Bioavailability and Pharmacokinetics of Anisatin in Mouse Blood by Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry
- Author
-
Xiajuan Jiang, Quan Zhou, Jianshe Ma, Xianqin Wang, and Xi Bao
- Subjects
Male ,Article Subject ,Electrospray ionization ,Biological Availability ,Mass spectrometry ,Sensitivity and Specificity ,01 natural sciences ,High-performance liquid chromatography ,General Biochemistry, Genetics and Molecular Biology ,Lactones ,Mice ,chemistry.chemical_compound ,Tandem Mass Spectrometry ,Liquid chromatography–mass spectrometry ,Animals ,Protein precipitation ,Spiro Compounds ,Chromatography, High Pressure Liquid ,Chromatography ,General Immunology and Microbiology ,010405 organic chemistry ,Chemistry ,010401 analytical chemistry ,Selected reaction monitoring ,Reproducibility of Results ,General Medicine ,0104 chemical sciences ,Bioavailability ,Anisatin ,Linear Models ,Medicine ,Sesquiterpenes ,Research Article - Abstract
Background. Anisatin is a neurotoxic sesquiterpene dilactone wildly found in plants of the family Illiciaceae. Due to morphological similarities among Illiciaceae fruits, fatal poisonings are frequent. Objective. This study is aimed at developing a rapid, simple ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method to determine anisatin’s bioavailability in mouse blood and the method’s application to pharmacokinetics. Methods. Blood samples were preprocessed by protein precipitation using acetonitrile. Salicin (internal standard, IS) and anisatin were gradient-eluted by a mobile phase of methanol and water (0.1% formic acid) in a UPLC BEH C18 column. This step involved using an electrospray ionization source of anisatin at a mass-to-charge ratio (m/z) of 327.1 → 127.0 and IS at m/z 285.1 → 122.9 in the negative ion mode with multiple reaction monitoring. Results. The calibration curve ranged from 1 to 2000 ng/ml ( r > 0.995 ), with the method’s accuracy ranging from 86.3% to 106.9%. Intraday and interday precision were lower than 14%, and the matrix effect was between 93.9% and 103.3%. The recovery rate was higher than 67.2%. Conclusions. The developed UPLC-MS/MS method was successfully used for a pharmacokinetic study of oral (1 mg/kg) and intravenous (0.5 mg/kg) administration of anisatin to mice—the absolute bioavailability of anisatin in the mouse blood was 22.6%.
- Published
- 2020
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