39 results on '"Yan, Xiaoming"'
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2. Water-Free Cyclosporine Ophthalmic Solution vs Vehicle for Dry Eye Disease: A Randomized Clinical Trial
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Peng, Rongmei, Jie, Ying, Long, Qin, Gong, Lan, Zhu, Lei, Zhong, Xingwu, Zhao, Shaozhen, Yan, Xiaoming, Gu, Hao, Wu, Huping, Li, Gang, Zhang, Kaiyun, Krösser, Sonja, Xu, Ruxia, and Hong, Jing
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IMPORTANCE: Dry eye disease (DED) is a prevalent eye disorder. Cyclosporine is an effective immunomodulator that is widely used in DED; however, due to its highly hydrophobic nature, delivery of cyclosporine to the ocular surface is challenging. OBJECTIVE: To evaluate the efficacy and safety of SHR8028, a water-free cyclosporine ophthalmic solution, 0.1%, compared with vehicle in Chinese participants with DED. DESIGN, SETTING, AND PARTICIPANTS: This was a multicenter, double-blind, vehicle-controlled, phase 3 randomized clinical trial conducted from March 4, 2021, to July 22, 2022. Adult participants with moderate to severe DED were recruited from 12 hospitals in China. Study data were analyzed April 2, 2022, for the primary analysis. INTERVENTIONS: Following a 14-day run-in period with an artificial tear, participants were randomly assigned (1:1) to receive water-free cyclosporine or vehicle (1 eye drop in each eye twice daily). After a 29-day treatment, participants of both groups were given the option to receive water-free cyclosporine for an additional 12 weeks for longer-term safety assessment. MAIN OUTCOMES AND MEASURES: The primary end points were changes from baseline in total corneal fluorescein staining (tCFS) using the National Eye Institute scale and in dryness score on a visual analog scale at day 29. RESULTS: A total of 206 participants (mean [SD] age, 47.8 [14.2] years; 185 female [90%]) were enrolled, with 103 each in the cyclosporine group and the vehicle group. At day 29, the cyclosporine group experienced improved tCFS compared with vehicle (change [Δ] = −1.8; 95% CI, −2.7 to −1.0; P < .001), with a tCFS score decrease from baseline of −4.8 in the cyclosporine group and −3.0 in the vehicle group. Dryness score decreased from baseline in both groups (−19.2 vs −15.4; Δ = −3.8; 95% CI, −9.2 to 1.6; P = .17). During the 29-day treatment, treatment-related adverse events were reported in 15 participants (14.6%) in the cyclosporine group and 11 participants (10.7%) in the vehicle group. CONCLUSIONS AND RELEVANCE: Results demonstrated superiority of a water-free cyclosporine, 0.1%, eye solution over vehicle in improving tCFS score at day 29 in Chinese participants with DED. However, dryness score (VAS) was not improved at day 29. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05841043
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- 2024
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3. Engineering of Interconnected Ionic Channels in Polybenzimidazole Anion-Exchange Membranes
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Yang, Ruizhen, Wu, Xuemei, Chen, Wanting, Wang, Xiaozhou, Li, Tiantian, Yan, Xiaoming, Wang, Leilei, Cui, Fujun, and He, Gaohong
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To balance the ion conduction and stability of anion-exchange membranes (AEMs), the efficiency of OH–transfer needs to be improved. Here a series of polybenzimidazole-based AEMs (UTA-PBI-x) with comb-shaped tricationic side chains containing two diethoxy spacers and one alkyl spacer were synthesized. It is found that in the low-IEC region, hydrogen-bond network is the dominant contribution to ion transport, while the hydrated ionic channels would gradually become more dominant with increasing ionic content. With an optimal IEC of 1.40 mmol/g, OH–ions could rapidly transfer in the desired hydrated cationic clusters and through the thin intercluster ether-containing hydrogen-bond network domains. Meanwhile, the ether domains guarantee a continuous nonionic phase for resisting water swelling. Consequently, the UTA-PBI-1.40 membrane simultaneously possesses a low swelling ratio of 17.2%, sufficient conductivity of 46.9 mS/cm at 20 °C, excellent mechanical strength (21.1 MPa), and good alkaline stability (∼90% remaining conductivity) in 1 M NaOH for ∼1400 h. A high efficiency of OH–transport (σ/IEC ∼ 103.2) was achieved, which is superior to those of the recently reported AEMs. In a H2/O2fuel cell, the ultrathin UTA-PBI-1.40 membrane achieves a peak power density of 861.6 mW/cm2at 80 °C. This work provides a theoretical and experimental guidance for the design of AEMs with high-efficient OH–transfer.
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- 2023
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4. Radiomics features from 3D‐MPRAGEimaging can differentiate temporal‐plus epilepsy from temporal lobe epilepsy
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Yin, Fangzhao, Yan, Xiaoming, Gao, Runshi, Ren, Zhiwei, Yu, Tao, Zhao, Zhuoling, and Zhang, Guojun
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This study aimed to differentiate temporal‐plus epilepsy (TPE) from temporal lobe epilepsy (TLE) using extraction of radiomics features from three‐dimensional magnetization‐prepared rapid acquisition gradient echo (3D‐MPRAGE) imaging data. Data from patients with TLE or TPE who underwent epilepsy surgery between January 2019 and January 2021 were retrospectively analyzed. Thirty‐three regions of interest in the affected hemisphere of each patient were defined on 3D‐MPRAGE images. A total of 3531 image features were extracted from each patient. Four feature selection methods and 10 machine learning algorithms were used to build 40 differentiation models. Model performance was evaluated using receiver operating characteristic analysis. Eighty‐two patients were included for analysis, 47 with TLE and 35 with TPE. The model combining logistic regression and the relief selection method had the best performance (area under the receiver operating characteristic curve, .779; accuracy, .875; sensitivity, .800; specificity, .929; positive predictive value, .889; negative predictive value, .867). Radiomics analysis can differentiate TPE from TLE. The logistic regression classifier trained with radiomics features extracted from 3D‐MPRAGE images had the highest accuracy and best performance.
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- 2023
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5. Backstepping-Based Direct Power Control for Dual-Cage Rotor Brushless Doubly Fed Induction Generator
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Yan, Xiaoming and Cheng, Ming
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In this article, we propose a backstepping (BS)-based direct power control (DPC) strategy for the dual-cage rotor brushless doubly fed induction generator (DCR-BDFIG). The relationship between the power winding (PW) output power and the control winding (CW) voltage is derived according to the complete mathematical model of DCR-BDFIG. Based on that, a BS-based DPC controller, also known as a nonlinear controller, is designed with the global asymptotic stability analyzed for the grid-connected DCR-BDFIG. Compared with the dual-closed-loop control in the advanced vector control method, only single-closed-loop is required for the PW power in the proposed BS-based control scheme, and thus it has more simple structure and faster responses. The global stability of the proposed control scheme can be easily guaranteed with a Lyapunov function properly selected. In addition, in order to improve the performance of the proposed BS-based DPC strategy under unbalanced network, the resonant controller is introduced to suppress the oscillating components in the PW power, PW current, and CW current, whose harmonic order is twice of the grid frequency referring to the synchronous reference frame. Finally, the detailed experimental results demonstrate the effectiveness of the proposed control strategy.
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- 2023
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6. Optimal pricing and inventory control policy with quantity-based price differentiation
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Lu, Ye, Chen, Youhua "Frank", Song, Miao, and Yan, Xiaoming
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Dynamic programming -- Usage ,Pricing -- Analysis ,Inventory control -- Analysis ,Product price ,Business ,Mathematics - Abstract
A firm facing price dependent stochastic demand aims to maximize its total expected profit over a planning horizon. In addition to the regular unit selling price, the firm can utilize [...]
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- 2014
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7. Optimal control problems for a new product with word-of-mouth
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Yan, Xiaoming and Liu, Ke
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Business ,Business, international ,Engineering and manufacturing industries - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ijpe.2009.03.011 Byline: Xiaoming Yan (a)(b), Ke Liu (a) Abstract: In this paper, we consider a firm to maximize its profit by choosing a production capacity and determining the production and sales policies for a new product during the lifetime of the product. We extend Bass demand process into more general case including the negative effectiveness of word-of-mouth. Under some mild conditions, we show that the optimal sales policy is myopic, then we obtain the closed forms of the optimal production and sales policies in three cases. Furthermore, we can determine the optimal production capacity by solving several equations. Author Affiliation: (a) Institute of Applied Mathematics, Academy of Mathematics and Systems Sciences, Chinese Academy of Sciences, Beijing 100190, PR China (b) School of Computer, Dongguan University of Technology, Guangdong, PR China Article History: Received 13 September 2007; Accepted 6 March 2009
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- 2009
8. Design and analysis of a dual-stator brushless doubly-fed induction machine with a staggered dual-cage rotor
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Cheng, Ming, Zeng, Yu, Yan, XiaoMing, and Zhang, ChangGuo
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In this paper, a new dual-stator brushless doubly-fed induction machine with a staggered dual cage rotor is proposed, with emphasis on the general interconnection rule of the conductor bars for the staggered dual cage rotor. Since the squirrel cage rotor offers the merits of robustness, reliable structure, high slot filling factor, and low rotor resistance comparing to the wound rotor, it is introduced to the dual-stator brushless doubly-fed induction machine to solve the problems of high copper loss and unreliable rotor structure for the dual-stator brushless doubly-fed induction machine with a wound rotor. The originality of this article is to investigate the interconnection rule of conductor bars between the inner and outer cages. The constraint condition that is supposed to be satisfied is deduced by using the rotating magneto-motive force theory, based on which diverse slot/pole combinations are investigated. The performance comparison between the existing and proposed machines is conducted. Finally, a prototype is designed and fabricated. The experimental results verify the effectiveness of the proposed topology.
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- 2022
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9. Prognostic value of high-frequency oscillations combined with multimodal imaging methods for epilepsy surgery
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Yan, Xiaoming, Yin, Fangzhao, Xu, Cuiping, Yu, Tao, Li, Xiaonan, Wang, Wei, Zhang, Xi, Ma, Kai, Zhang, Guojun, and Guo, Lishao
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- 2022
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10. Isolated retro-orbital granulocytic sarcoma relapse of Acute Myeloid Leukemia after allogeneic hematopoietic stem cell transplantation: a case report
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Sun, Xiaona, Rong, Xin, Nie, Hongping, and Yan, Xiaoming
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Background: Granulocytic sarcoma (GS) is rare as an isolated presentation of relapse after allogeneic hematopoietic stem-cell transplantation (allo-HSCT), particularly in adult patients with acute myelogenous leukemia (AML). We report here the case of a 37-year-old man who developed a GS of the retro-orbital as an isolated manifestation of AML relapse 27 months after allo-HSCT.Case report: A 37-year-old man was diagnosed with AML and subsequently received allo-HSCT after clinical chemical remission. The patient suddenly presented with painless exophthalmos of the left eye twenty-seven months after allo-HSCT. Orbital magnetic resonance imaging (MRI) revealed left retro-orbital masses. Histopathology revealed diffused infiltration of leukemic blasts. Further systemic investigation showed no leukemic involvement of his other organs. Isolated retro-orbital relapse of AML was diagnosed. Despite treatment using retro-orbital irradiation, the patient died 6 months after presentation.Conclusion: Our patient had a poor survival prognosis, even with timely diagnosis and proper treatment. Although the ophthalmologist has a secondary role in the diagnosis and treatment of leukemia, a prompt recognition of the ocular manifestations and their significance as a sign of possible extramedullary lesion is crucial.
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- 2022
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11. A Covalent Organic Framework Membrane with Homo Hierarchical Pores for Confined Reactive Crystallization
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Wu, Mengyuan, Jiang, Xiaobin, Meng, Yingshuang, Niu, Yuchao, Yuan, Zhijie, Du, Shaofu, Li, Xiangcun, Ruan, Xuehua, Xiao, Wu, Yan, Xiaoming, and He, Gaohong
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Gas–liquid (G–L) reactive crystallization is a major technology for advanced materials construction, which requires a short diffusion path on the interface to ensure the reactant supply and stable crystal nucleation under ultrahigh supersaturation. Herein, a covalent organic framework (COF) membrane with homo hierarchical pore structures was proposed as an effective interfacial material for the regulation of confined reactive crystallization. By combining the ordered nanopores of COFs and micropores of anodic aluminum oxide (AAO), the COF membrane simultaneously provided an excellent nanoscale diffusion–reaction regulation network as the molecular-level confined G–L reactive interface and adjustable submicrometer gas mass transfer channels. The highly selective construction of CaCO3superstructures was then achieved. When the submicrometer primary pore size rpof the constructed COF membrane ranged from 120 to 1.6 nm, the diffusion mechanism of CO2varied from viscous flow diffusion to Knudsen diffusion. The growth orientation of CaCO3crystals was well confined to obtain spindle-shaped crystals with high selectivity. Meanwhile, the crystal selectivity factor (cube/sphere) increased from 0 to 3.53 under the low interfacial nuclear barrier. Thus, the COF membrane with coupled micro-nanostructures successfully screened the directional preparation conditions for diverse CaCO3superstructures, which also paved a meaningful path for the functional application of COFs in accurate mass transfer control and confined chemical reactions.
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- 2022
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12. Membrane-Assisted Cooling Crystallization for Interfacial Nucleation Induction and Self-Seeding Control
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Xiao, Wu, He, Zeman, Shao, Guanying, Li, Peiyu, Ruan, Xuehua, Yan, Xiaoming, Wu, Xuemei, Li, Xiangcun, He, Gaohong, and Jiang, Xiaobin
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Accurate cooling crystallization control has a significant impact on terminal crystal product quality. Herein, a hollow fiber membrane-assisted cooling crystallization (MACC) was investigated to achieve nucleation induction and self-seeding operation. Poly(tetrafluoroethylene) (PTFE) and polyethersulfone (PES) membranes with thermal conduction properties were introduced to accelerate the nucleation at a supercooled membrane surface, and the detached crystal seeds were then transferred into the crystallizer. A polymeric membrane can achieve nucleation control and hinder the potential secondary nucleation, which has been validated by online detection experiments. This advantage rendered excellent MACC performance in the manufacture of high-purity thiourea crystals, which possessed the desired morphology, a large mean size (>1.35 mm), high purity (>99.5 wt %), and narrower size distribution.
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- 2022
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13. Oxidative stress in corneal stromal cells contributes to the development of keratoconus in a rabbit model
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Liu, Ruixing and Yan, Xiaoming
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Purpose: To investigate the role of oxidative stress in keratocytes in the pathogenesis of keratoconus (KC) using the rabbit cornea as a model.Methods: Immerse the rabbit cornea in collagenase type II solution at room temperature for 30 min in the KC group. The central cornea thickness (CCT), and mean keratometry (Km) were examined before and after the procedure. Reactive oxygen species (ROS), the nuclear translocation of nuclear factor E2-related factor 2 (NRF-2), the expression of heme oxygenase-1 (HO-1) protein, and nicotinamide adenine dinucleotide phosphate (NADPH) Oxidase (NOX) family members NOX-2 and NOX-4 protein levels were examined by immunohistochemistry analysis and Western Blot. The expression levels of HO-1, NOX-2, NOX-4, and NRF-2 mRNA were quantitatively detected by Real-time PCR.Results: A significant increase in Km and a significant decrease in CCT were observed in the KC group compared with the control group after the surgery (both p< 0.001). Immunofluorescence staining showed the rabbit KC model induced a significant increase in ROS production (p< 0.001). The expression of HO-1, NOX-2, NOX-4, and NRF-2 proteins in the KC group were significantly higher than those in the control group (all p< 0.001). RT-PCR results showed the levels of HO-1, NOX-2, NOX-4, and NRF-2 mRNA in KC groups were all significantly increased compared with control groups (all p< 0.05).Conclusions: Oxidative stress and compensatory activation of antioxidant proteins suggest oxidative stress injury in corneal stromal cells plays an important role in the development of KC in a rabbit model.
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- 2021
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14. Fuzzy neuron modeling of incomplete data for missing value imputation.
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Zhang, Zheng, Yan, Xiaoming, Zhang, Liyong, Lai, Xiaochen, and Lu, Wei
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MISSING data (Statistics) , *DATA modeling , *NEURONS - Abstract
• A category-based TS-TRAE model is proposed for incomplete data modeling and missing value imputation. • An iterative learning method is proposed, which updates the missing value variables and model parameters collaboratively. • Incomplete samples are allowed to participate in modeling, which fully uses existing value information. Missing values are a common problem found in many real-world datasets, and cannot be avoided. It is a challenging task to model incomplete data and reasonably impute missing values. This paper focuses on regression imputation and uses a tracking-removed autoencoder (TRAE) to construct the mutual fitting correlation on incomplete data. Considering the differences in regression relationships across different sample categories, we introduce Takagi-Sugeno (TS) fuzzy architecture and propose a category-based tracking-removed autoencoder (TS-TRAE) to model incomplete data for missing value imputation. The TS-TRAE model partitions the incomplete dataset into several subclusters using membership information obtained from fuzzy clustering, then establishes a TRAE-based submodel to mine relationships within each subcluster for precise modeling of incomplete data. During model training, in order to fully utilize all existing values, we treat missing values as variables and propose an iterative learning method that optimizes missing variables and network parameters collaboratively. This method allows incomplete samples to participate in model training while also enabling the imputation of missing values. The TS-TRAE model integrates the inner category structure of incomplete data and the attribute association features effectively. The experimental results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Scalable fabrication of integrated covalent organic framework membrane with selective ion transport for efficient salinity gradient energy harvesting
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Sun, Xiaojun, Di, Mengting, Gao, Li, Jiang, Xiaobin, Ruan, Xuehua, Yan, Xiaoming, and He, Gaohong
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Interfacial polymerization (IP) is a promising approach for preparing covalent organic framework (COF) membranes in energy storage and conversion applications. However, it is a great challenge for traditional IP with water-organic phase to obtain pre-designable and robust COF membranes. Herein, a "one-pot" organic-organic IP/in situ integration approach, constructing three typical β-ketoenamine COF composite membranes with a maximum area of >600 cm2, are reported. The dual organic phases exhibit comprehensive solubility to precursors, facilitating the synthesis of more types of COFs. In this "one-pot" approach, the porous supporting substrate is in situ formed underneath the COF layer via variable-temperature evaporation of two organic solutions without transfer process. It makes some substrate polymers embedded into the COF layer and accomplishes the interlock of two layers at the interface, producing a robust composite membrane. The prepared COF composite membrane exhibits effective sieving capability for Na+/Mg2+and achieves a maximum power density of over 1Wm−2in the reverse electrodialysis power generation, even using the Na+/Mg2+mixed solution. This approach allows for preferably customization of membrane structures, which can expand the applications of COF membranes in separation.
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- 2024
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16. A new long-side-chain sulfonated poly(2,6-dimethyl-1,4-phenylene oxide)/polybenzimidazole amphoteric membrane for vanadium redox flow battery
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Jiang, Bowen, Hu, Lei, Yan, Xiaoming, Sun, Jiahui, Gao, Li, Dai, Yan, Ruan, Xuehua, and He, Gaohong
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A new amphoteric membrane was prepared by blending long-side-chain sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) (S-L-PPO) and polybenzimidazole (PBI) for vanadium redox flow battery (VRFB) application. An acid–base pair structure formed between the imidazole of PBI and sulfonic acid of S-L-PPO resulted in lowered swelling ratio. It favors to reduce the vanadium permeation. While, the increased sulfonic acid concentration ensured that proton conductivity was still at a high level. As a result, a better balance between the vanadium ion permeation (6.1 × 10−9 cm2·s−1) and proton conductivity (50.8 mS·cm−1) in the S-L-PPO/PBI-10% membrane was achieved. The VRFB performance with S-L-PPO/PBI-10% membrane exhibited an EE of 82.7%, which was higher than those of pristine S-L-PPO (81.8%) and Nafion 212 (78.0%) at 120 mA·cm−2. In addition, the S-L-PPO/PBI-10% membrane had a much longer self-discharge duration time (142 h) than that of Nafion 212 (23 h).
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- 2024
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17. Completely Methylene-Free Side Chain Enables Significant Microphase Separation at Medium IECs for Fuel-Cell Anion Exchange Membranes
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Gong, Shoutao, Liu, Anmin, Qaisrani, Naeem Akhtar, Han, Long, Yuan, Minghao, Ren, Yanzhen, Yan, Xiaoming, He, Gaohong, and Zhang, Fengxiang
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The introduction of hydrophobic side chain structures in anion exchange membranes (AEMs) to facilitate ion transport has been widely studied; however, low or moderate hydrophobic hydrocarbon and semifluorinated side chains are insufficient to induce a high degree of microphase separation. Herein, we design and prepare poly(aryl piperidinium) AEMs with completely methylene-free perfluorinated side chains, which can maximize the thermodynamic incompatibility between main- and side chains, thus enhancing microphase separation at medium ion exchange capacities (IECs). According to the molecular dynamics study, the methylene-free perfluorinated side chain leads to better hydration of cations. The hydroxide conductivity of the methylene-free perfluorinated side chain-grafted PAP-pF-1 membrane reaches 124.9 mS cm–1at 80 °C, and the PAP-sF-1 with semifluorinated side chains and PAP-CH-1 with hydrocarbon side chains show lower conductivity (116.8 and 104.0 mS cm–1). The H2/O2fuel cell using the PAP-pF-1 membrane demonstrates a remarkable peak power density (1651 mW cm–2at 80 °C) and durability (greater than 300 h). This work provides a novel insight into enhancing microphase separation in AEMs; it opens up new possibilities for developing high-performance AEMs.
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- 2024
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18. Study on the Microbial Mechanisms of Enhancing Agaricus bisporusGrowth through Inoculation with Pseudomonas putida
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Li, Hongtu, Liu, Lanhua, Xu, Boyang, Yan, Xiaoming, Chen, Qun, Wu, Xiaolei, Wu, Xunfeng, Mu, Dongdong, and Li, Xingjiang
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Introducing Pseudomonas putidaoptimizes the microbial community within the casing layer, thereby enhancing Agaricus bisporusgrowth. Nevertheless, the underlying mechanisms governing microbial community succession within the casing layer following microbial agent introduction remained elusive. This study delineated the interplay among microbial populations in the casing layer across the growth cycle of A. bisporus, comparing cohorts treated with P. putida(AP) against untreated controls (CK). The inoculation with Pseudomonaspromoted the growth of A. bisporus, shortened its growth cycle, and linearly enhanced the relative abundance of key bacterial genera integral to its growth, including Flavobacterium, Rhodoferax, Pseudarthrobacter, and Vogesella(adjusted R2=0.238-0.866). Importantly, a positive correlation was identified between the proliferation of these beneficial bacteria and positive community cohesion (adjusted R2=0.353-0.838). Additionally, analysis of the symbiotic network topology within the AP group indicated a more stable community following inoculation. The niche results (AP=11.7672±1.8938, CK=11.0481±3.1273, P<0.05) underscored the positive impact of Pseudomonasinoculation on ecosystem dynamics. Concentrations of essential nutrients for A. bisporusgrowth, notably readily available phosphorus (On day 17, the AP group was 78.8333±1.26623 mg/kg, while the CK group was 30.0333±0.98658 mg/kg) and readily available potassium (On day 17, the AP group was 2693.9±14.79561 mg/kg, while the CK group was 1646.9333±10.71276mg/kg), were significantly elevated in the AP group. These enhancements strongly correlated with the increased abundance of pivotal microbial populations. Our research provided insights into the application of microbial inoculants to enhance the production of edible fungi.
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- 2024
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19. Electron-Donating C-NH2Link Backbone for Highly Alkaline and Mechanical Stable Anion Exchange Membranes
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Zhang, Fan, Li, Tiantian, Chen, Wanting, Wu, Xuemei, Yan, Xiaoming, Xiao, Wu, Zhang, Yang, Wang, Xiaozhou, and He, Gaohong
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Aryl-ether cleavage and benzylic quaternary ammonium (QA) group degradation are promoted by C═O groups in most commercial anion exchange membrane materials. Herein, a novel strategy of converting C═O groups to the electron-donating C-NH2linkages in conventional poly(arylene ether ketone)s is proposed by reductive amination via Leuckart reaction. Density functional theory (DFT) calculations indicate that the model compound containing C-NH2linkage exhibits much higher barrier heights for aryl-ether cleavage and QA group degradation by enhancing the electronic cloud density on both the ether-connected carbon and the benzylic carbon. The C-NH2linkages also induce hydrogen bond networks in the membranes, which enhance intermolecular interaction and provide additional hydroxide transport sites. As a result, the C-NH2linkage membranes exhibit excellent hydroxide conductivity (108.2 mS cm–1at 80 °C) and tensile strength (48.4 MPa) with high elongation at break (50.8%). The C-NH2linkage membranes also show outstanding alkaline stability with no detectable backbone degradation even in 4 M KOH at 80 °C for 400 h, which is at the top-level among the state-of-the-art main chain architecture AEMs. This study proposes a new strategy for the synthesis of highly stable AEMs based on electron-donating C-NH2link backbone.
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- 2021
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20. High-Performance Anion Exchange Membranes with Para-Type Cations on Electron-Withdrawing C═O Links Free Backbone
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Zhang, Fan, Li, Tiantian, Chen, Wanting, Yan, Xiaoming, Wu, Xuemei, Jiang, Xiaobin, Zhang, Yang, Wang, Xiaozhou, and He, Gaohong
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As critical triggers, both the electron-withdrawing links and neighboring cationic groups induce and accelerate the aryl ether cleavage in the widely used aryl ether containing anion exchange membranes (AEMs). Herein, a novel alkaline stable polyelectrolyte is proposed by converting the electron-withdrawing C═O links in the widely used poly(aryl ether ketone) backbone into the electron-donating C–NH2links, and then grafting faraway para-type cations by Leuckart-Menshutkin reaction without using noble metal catalysts. Contributions of the elimination of electron-withdrawing C═O links and graft of para-type cations to the excellent alkaline stability of the aryl ether containing polyelectrolytes are demonstrated through density functional theory, as the increasing electron cloud density on the ether-connected carbon atom elevates the activation energy barrier to OH–initiated aryl ether cleavage, and the para-type cation is more stable than the conventional ortho-type cation due to the sterical protection and low electrophilicity to benzylic carbon. By converting C═O to C–NH2groups and then tuning the quaternization degree, the remaining C–NH2groups in the polymer backbone could form hydrogen bonding networks to reinforce the membranes. The novel quaternized poly(aryl ether amine) membrane exhibits high conductivity (92.2 mS cm–1at 80 °C), excellent mechanical properties (48.2 MPa, 51.3%), and suppressed swelling ratio (12.8% at 80 °C). Excellent alkaline stability is also confirmed experimentally with no polymer backbone degradation even in harsh conditions (4 M KOH, 80 °C, 400 h), which is at the top level among the state-of-the-art side chain and aryl ether-free types of AEMs.
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- 2020
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21. Bioinspired Hybrid Micro/Nanostructure Composited Membrane with Intensified Mass Transfer and Antifouling for High Saline Water Membrane Distillation
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Jiang, Xiaobin, Shao, Yushan, Li, Jin, Wu, Mengyuan, Niu, Yuchao, Ruan, Xuehua, Yan, Xiaoming, Li, Xiangcun, and He, Gaohong
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Membrane distillation (MD) holds great promise for high-saline solution treatment, but it is typically impeded by the trade-off between the high mass transfer and antifouling properties of the membrane. Herein, a new MD utilized membrane with bioinspired micro/nanostructure (lotus leaf and fish gill) was constructed on commercial PP membrane, which can simultaneously enhance the permeation flux and antifouling in the hypersaline MD operation. On the basis of the classic nucleation theory and hydrodynamics simulation, the nanoscale structure can intensify the interfacial nanoscale turbulent flow and hinder the crystal deposition, which works like the fish gill. In addition, the optimized nanoscale feature size renders the membrane with the heterogeneous nucleation barrier very similar to the homogeneous system, which works like the lotus leaf and hinders the induced nucleation effectively. The microscale structure as the supporting platform of nanostructure can additionally enlarge the effective evaporative surface with superior hydrophobicity and then promote the permeation transfer through the membrane. The hybrid micro/nanostructures render the fabricated membrane with excellent high-permeation flux and significantly prolonged fouling induction time, which sheds light on a new approach for the development of ideal MD utilized membrane.
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- 2020
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22. Permeability of N, P, K-fertilizer nutrient and water vapor through PLA, PLA/PS, and PLA/HA membranes
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Deng, Xiaonan, Ye, Sihong, Liu, Kun, Li, Changfeng, Liu, Fangzhi, and Yan, Xiaoming
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To collect permeability data and establish its database of fertilizer nutrients and water vapor through different polymer membranes for the development of polymer-coated fertilizer, the permeabilities of N-, P-, and K-nutrient from saturated aqueous of urea, NaH2PO4and KCl solution and the permeability of water vapor through the membranes of poly lactic acid (PLA), its blends with polystyrene (PS), and its composites with humic acid (HA) particles were determined experimentally at the temperatures of 288, 298, and 308 K, respectively. The effects of the addition of PS and HA particles, temperature, and coating thickness on the permeability of fertilizer nutrient and water vapor were investigated. It was found that the addition of PS and HA increased the permeability for both the fertilizer nutrients and water vapor. The increase in temperature raised the permeability of N-, P-, and K-nutrient while decrease the permeability of water vapor in the range studied.
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- 2020
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23. Sulfonated polybenzimidazole/amine functionalized titanium dioxide (sPBI/AFT) composite electrolyte membranes for high temperature proton exchange membrane fuel cells usage
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Imran, Muhammad A., Li, Tiantian, Wu, Xuemei, Yan, Xiaoming, Khan, Abdul-Sammed, and He, Gaohong
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The novel sulfonated polybenzimidazole (sPBI)/amine functionalized titanium dioxide (AFT) composite membrane is devised and studied for its capability of the application of high temperature proton exchange membrane fuel cells (HT-PEMFCs), unlike the prior low temperature AFT endeavors. The high temperature compatibility was actualized because of the filling of free volumes in the rigid aromatic matrix of the composite with AFT nanoparticles which inhibited segmental motions of the chains and improved its thermal stability. Besides, amine functionalization of TiO2enhanced their dispersion character in the sPBI matrix and shortened the interparticle separation gap which finally improved the proton transfer after establishing interconnected pathways and breeding more phosphoric acid (PA) doping. In addition, the appeared assembled clusters of AFT flourished a superior mechanical stability. Thus, the optimized sPBI/AFT (10 wt%) showed 65.3 MPa tensile strength; 0.084 S·cm−1proton conductivity (at 160 °C; in anhydrous conditions), 28.6% water uptake and PA doping level of 23 mol per sPBI repeat unit. The maximum power density peak for sPBI/AFT-10 met the figure of 0.42 W·cm−2at 160 °C (in dry conditions) under atmospheric pressure with 1.5 and 2.5 stoichiometric flow rates of H2/air. These results affirmed the probable fitting of sPBI/AFT composite for HT-PEMFC applications.
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- 2020
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24. Membrane-Assisted Antisolvent Crystallization: Interfacial Mass-Transfer Simulation and Multistage Process Control
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Li, Jin, Sheng, Lei, Tuo, Linghan, Xiao, Wu, Ruan, Xuehua, Yan, Xiaoming, He, Gaohong, and Jiang, Xiaobin
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Antisolvent crystallization is an important purification technology for the pharmaceutical and fine chemical industries. Herein, we investigated the mass-transfer mechanism of membrane-assisted antisolvent crystallization (MAAC) and developed a multistage operation to reinforce the manufacturing features of antisolvent crystallization. Computational fluid dynamics simulation results via a developed mathematics model and the experimental images via in situ detection technology jointly illustrated the advantages of MAAC for accurate mass-transfer control. Further, a three-stage MAAC process was investigated to reveal the process control performance. The diverse functional regions of multistage MAAC under different antisolvent addition strategies were then highlighted by manufacturing the crystal products with a narrow size distribution, a uniform aspect ratio, and the desired morphology. Multistage MAAC that intensifies the product capacity under a stable control is a promising direction for new-generation antisolvent crystallization.
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- 2020
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25. Amphoteric-Side-Chain-Functionalized “Ether-Free” Poly(arylene piperidinium) Membrane for Advanced Redox Flow Battery
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Yan, Xiaoming, Zhang, Huaqing, Hu, Zhongyue, Li, Lv, Hu, Lei, Li, Zhi’ang, Gao, Li, Dai, Yan, Jian, Xigao, and He, Gaohong
- Abstract
To solve the stability issue of cost-effective nonfluorinated membranes, an ether-free poly(arylene piperidinium) (PBPip)-based membrane is first applied in redox flow batteries (RFBs). For improved efficiencies of RFB, amphoteric side chains are introduced onto the PBPip. Without an ether bond in the polymer backbone, the membrane shows a good stability in a strong oxidation environment. The Fourier transform infrared (FTIR) spectra exhibit no obvious changes over 30 days of oxidation test. Different from traditional blended amphoteric membranes, the amphoteric side chain allows both cation- and anion-exchange capacities to increase with grafting degree, which leads to a very high total ion-exchange capacity (IEC) (4.19 mmol g–1). Outstanding ion-conduction ability (area resistance: 0.22 Ω cm2) comparable to Nafion 212 (0.24 Ω cm2) is consequently achieved. Ionic cross-linking structure between cationic and anionic groups results in a low swelling rate (13.9%). Combined with the repelling effect of positively charged piperidinium, a low VO2+permeability (1.31 × 10–8cm2s–1) is accomplished. On the basis of these good properties, the membrane exhibits excellent vanadium battery performances, especially at high current densities. The VE and EE both exceed 80% even at 200 mA cm–2. The battery performances have no obvious reductions after 500 cycles. These results indicate that this work provides a new orientation to design the membrane for RFB.
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- 2019
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26. Novel Triple Tertiary Amine Polymer-Based Hydrogen Bond Network Inducing Highly Efficient Proton-Conducting Channels of Amphoteric Membranes for High-Performance Vanadium Redox Flow Battery
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Zhang, Huaqing, Yan, Xiaoming, Gao, Li, Hu, Lei, Ruan, Xuehua, Zheng, Wenji, and He, Gaohong
- Abstract
A novel amphoteric membrane was designed by blending triple tertiary amine-grafted poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-TTA) with sulfonated poly(ether ether ketone) (SPEEK) for vanadium redox flow batteries. An “acid–base pair” effect is formed by the combination of the tertiary amine group and sulfonic group, and extra nonbonding amine groups could be protonated. Both of them constitute a hydrogen bond network, which facilitates proton conduction and also hinders vanadium permeability because of the lowered swelling ratio and Donnan effect. All these contribute to improve the ion selectivity of the membrane while maintaining ionic conductivity. Compared with other amphoteric and SPEEK-based membranes, the membrane exhibits an excellent performance. The amphoteric membrane containing 15% PPO-TTA exhibits an ultralow vanadium permeability of 3.4 × 10–9cm2s–1and a low area resistance of 0.39 Ω cm–2. Consequently, the cell assembled with this membrane shows excellent performances far superior to SPEEK and Nafion 212. The Coulombic efficiency and energy efficiency of the cell are 94.3–98.3 and 90.3–77.1% at 40–200 mA cm–2, respectively, and have no significant reductions after 200 cycles. This performance is at a high level among the amphoteric and SPEEK-based membranes reported in recent years. The cell’s open circuit voltage is maintained for up to 165 h. In addition, the membrane’s chemical stability is improved by the effective barrier to the vanadium ion.
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- 2019
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27. Poly (ether ether ketone ketone) based imidazolium as anion exchange membranes for alkaline fuel cells
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Li, Tiantian, Wu, Xuemei, Chen, Wanting, Yan, Xiaoming, Zhen, Dongxing, Gong, Xue, Liu, Jiafei, Zhang, Shaofeng, and He, Gaohong
- Abstract
An imidazolium functionalized poly (ether ether ketone ketone) (PEEKK-DImOH) anion exchange membrane (AEM) readily soluble in certain low-boiling-point solvents (isopropanol) is prepared. The solubility results are consistent with the results of molecular dynamics simulations. By varying the chloromethylation reaction temperature or concentrated sulfuric acid concentration of PEEKK, the degrees of chloromethylation of PEEKK are changed from 54% to 92%, the corresponding PEEKK-DImOH AEMs with the ion exchange capacities (IECs) of 1.14–1.65 mmol·g−1. The PEEKK-DImOH 92% AEM shows high hydroxide conductivity (31 mS·cm−1), suitable water uptake (94%) and acceptable swelling ratio (39%) at 60 °C. In addition, the PEEKK-DImOH AEMs possess good thermal and alkaline stability. The maximum power density (46.16 mW·cm−2) of fuel cell prepared with PEEKK-DImOH 92% AEM as exchange membrane and ionomer is much higher than that with commercial AHA membranes. All the above results indicate that the PEEKK used in this study is a promising AEM matrix material for alkaline fuel cells.
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- 2018
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28. Amphiprotic Side-Chain Functionalization Constructing Highly Proton/Vanadium-Selective Transport Channels for High-Performance Membranes in Vanadium Redox Flow Batteries
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Yan, Xiaoming, Zhang, Caimian, Dong, Ziwei, Jiang, Bowen, Dai, Yan, Wu, Xuemei, and He, Gaohong
- Abstract
A novel amphiprotic side-chain-functionalized membrane was for the first time designed for vanadium redox flow battery (VFB). Different from frequently used blending amphiprotic membranes, the one proposed here is allowed to possess high anion-exchange capacity (IECa) without sacrificing the cation-exchange capacity (IECc) because both IECaand IECcincreased with the grafting degree of side chains. Having a high IECa, the membrane prepared here exhibits an ultralow vanadium permeability (<10–8cm2s–1), which leads to very high Coulombic efficiencies (97–98% at 40–200 mA cm–2) of VFB and good cell self-discharge durability. Moreover, the high IECccontributes to a decent ionic conductivity (area resistance: 0.5 Ω cm–2), which ensures a high-voltage efficiency of the cell. On the basis of these good properties, the VFB single cell with this membrane achieves a high energy efficiency (e.g., 77.4% at 200 mA cm–2) that is higher than those of Nafion 212 and other reported amphiprotic membranes. These results indicate that the approach proposed here is an ideal option to prepare amphiprotic membranes for VFBs with high efficiency and good durability.
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- 2018
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29. Quaternary-ammonium-immobilized polystyrenes as efficient and reusable heterogeneous catalysts for synthesis of cyclic carbonate: Effects of linking chains and pendent hydroxyl group
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Yan, Xiaoming, Ding, Xuan, Pan, Yu, Xu, Xiaowei, Hao, Ce, Zheng, Wenji, and He, Gaohong
- Abstract
Spherical polystyrene-supported ammonium salts containing different linking chains between the support and ammonium groups were prepared as efficient and easily reusable heterogeneous catalysts for the cycloadditions of CO2and epoxides. The effects of the length of the linking chains and a hydroxyl group pendent on the linking chain on the catalytic performance of ionic liquid immobilized catalysts and their mechanisms were studied through experiments and density functional theory calculations. It was found that, compared with a short linking chain, a long chain can make the halogen anion more negative and provide a larger contact area of the catalysts with the reactants, thus enhancing the reaction kinetics. The hydroxyl group can stretch the C–O bonds of the epoxides, promoting the reaction thermodynamics. As a result, for the cycloaddition of propylene oxide, the yield of propylene carbonate is much higher for the catalyst with a long linking chain (yield: 91.4%) compared with the yield for that with a short chain (yield: 70.9%), and is further increased in the presence of pendent hydroxyl groups (yield: 98.5%). The catalyst also shows a high catalytic activity even at mild temperature and good reusability (yield: ≥ 96% for 10 cycles), and the selectivity is always above 99%.
- Published
- 2017
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30. Morphological Evaluation of Meibomian Glands in Children and Adolescents Using Noncontact Infrared Meibography
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Wu, Yuan, Li, Haili, Tang, Yun, and Yan, Xiaoming
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Purpose:To compare, in vivo, differences in meibomian gland morphology between children and adolescents.Methods:Sixty-nine patients were included in this study and divided into two groups: children (n = 31; age range: 3 to 11 years) and adolescents (n = 39; age range: 12 to 18 years). Images of meibomian glands were obtained by infrared meibography and analyzed using ImageJ software (developed by the National Institutes of Health; available at Sixty-nine patients were included in this study and divided into two groups: children (n = 31; age range: 3 to 11 years) and adolescents (n = 39; age range: 12 to 18 years). Images of meibomian glands were obtained by infrared meibography and analyzed using ImageJ software (developed by the National Institutes of Health; available at http://rsb.info.nih.gov/ij/download.html). Meibomian gland loss, the number of meibomian gland ducts, the relative width of the meibomian gland ducts, and the percent area of the meibomian gland acini were compared between the two groups.Results:Meibomian gland loss was found in both groups, but the meiboscore was not significantly different between the two groups (0.35 ± 0.6 vs 0.41 ± 0.8, Meibomian gland loss was found in both groups, but the meiboscore was not significantly different between the two groups (0.35 ± 0.6 vs 0.41 ± 0.8, t= −0.314, P> .05). The number of meibomian gland ducts (25.85 ± 3.25 vs 23.23 ± 3.06, t= −3.437, P< .05), relative width of the meibomian gland ducts (69.62% ± 5% vs 66.1% ± 7%, t= −2.454, P< .05), and percent area of the meibomian gland acini (57.7% ± 4% vs 55.5% ± 4%, t= 2.571, P< .05) in the upper eyelid were significantly greater in adolescents than in children. However, no significant differences were found in the lower eyelid between the two groups.Conclusions:Meibography is useful for the assessment of ocular surface conditions in children and adolescents. Meibomian gland loss occurs in both children and adolescents. The meibomian glands of the upper eyelid exhibit more morphological changes in adolescents than in children.[[J Pediatr Ophthalmol Strabismus.2017;54(2):78–83.]
- Published
- 2017
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31. New Perspectives on Dry Eye Definition and Diagnosis: A Consensus Report by the Asia Dry Eye Society
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Tsubota, Kazuo, Yokoi, Norihiko, Shimazaki, Jun, Watanabe, Hitoshi, Dogru, Murat, Yamada, Masakazu, Kinoshita, Shigeru, Kim, Hyo-Myung, Tchah, Hung-Won, Hyon, Joon Young, Yoon, Kyung-Chul, Seo, Kyoung Yul, Sun, Xuguang, Chen, Wei, Liang, Lingyi, Li, Mingwu, Liu, Zuguo, Liu, Zuguo, Sun, Xuguang, Chen, Wei, Deng, Yingping, Hong, Jing, Jie, Ying, Li, Mingwu, Li, Ying, Liang, Lingyi, Qi, Hong, Wang, Hua, Yan, Xiaoming, Yang, Wenzhao, Ye, Yufeng, Yuan, Jin, Zhang, Hong, Zhan, Hui, Zhang, Mingchang, Zhao, Shaozhen, Kim, Hyo-Myung, Tchah, Hungwon, Choi, Chul Young, Chung, Eui-Sang, Hyon, Joon Young, Kim, Hyun-Seung, Kim, Mee Kum, Myoung-Joon, Kim, Tae-Im, Lee, Do-Hyung, Lee, Hyung-Keun, Seo, Kyoung Yul, Song, Jong Suk, Yoon, Kyung-Chul, Tsubota, Kazuo, Yokoi, Norihiko, Amano, Shiro, Arita, Reiko, Dogru, Murat, Hori, Yuichi, Kawakita, Tetsuya, Kawashima, Motoko, Koh, Shizuka, Nishida, Kohji, Ogawa, Yoko, Shimazaki, Jun, Watanabe, Hitoshi, Yamada, Masakazu, and Yamaguchi, Masahiko
- Abstract
For the last 20 years, a great amount of evidence has accumulated through epidemiological studies that most of the dry eye disease encountered in daily life, especially in video display terminal (VDT) workers, involves short tear film breakup time (TFBUT) type dry eye, a category characterized by severe symptoms but minimal clinical signs other than short TFBUT. An unstable tear film also affects the visual function, possibly due to the increase of higher order aberrations. Based on the change in the understanding of the types, symptoms, and signs of dry eye disease, the Asia Dry Eye Society agreed to the following definition of dry eye: “Dry eye is a multifactorial disease characterized by unstable tear film causing a variety of symptoms and/or visual impairment, potentially accompanied by ocular surface damage.” The definition stresses instability of the tear film as well as the importance of visual impairment, highlighting an essential role for TFBUT assessment. This paper discusses the concept of Tear Film Oriented Therapy (TFOT), which evolved from the definition of dry eye, emphasizing the importance of a stable tear film.
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- 2017
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32. The control and optimization of macro/micro-structure of ion conductive membranes for energy conversion and storage
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Yan, Xiaoming, Zheng, Wenji, Ruan, Xuehua, Pan, Yu, Wu, Xuemei, and He, Gaohong
- Abstract
Ion conductive membranes (ICMs) are frequently used as separators for energy conversion and storage technologies of fuel cells, flow battery, and hydrogen pump, because of their good ion-selective conduction and low electronic conductivity. Firstly, this feature article reviews the recent studies on the development of new non-fluorinated ICMs with low cost and their macro/micro-structure control. In general, these new non-fluorinated ICMs have lower conductivity than commercial per-fluorinated ones, due to their poor ion transport channels. Increasing ion exchange capacity (IEC) would create more continuous hydrophilic channels, thus enhancing the conductivity. However, high IEC also expands the overall hydrophilic domains, weakens the interaction between polymer chains, enhances the mobility of polymer chains, and eventually induces larger swelling. The micro-scale expansion and macro-scale swelling of the ICMs with high IEC could be controlled by limiting the mobility of polymer chains. Based on this strategy, some efficient techniques have been developed, including covalent crosslinking, semi-interpenatrating polymer network, and blending. Secondly, this review introduces the optimization of macro/microstructure of both per-fluorinated and non-fluorinated ICMs to improve the performance. Macro-scale multilayer composite is an efficient way to enhance the mechanical strength and the dimensional stability of the ICMs, and could also decrease the content of perfluorosulfonic acid resin in the membrane, thereby reducing the cost of the per-fluorinated ICMs. Long side chain, multiple functionalization, small molecule inducing micro-phase separation, electrospun nanofiber, and organic–inorganic hybrid could construct more efficient ion transport channels, improving the ion conductivity of ICMs.
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- 2016
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33. The uptake of europium by reduced graphene oxide-supported nanoscale zerovalent iron investigated by batch and modeling techniques
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Zhu, Hongjie, Gao, Huiyi, Huang, Xiaoming, Kong, Weifang, and Yan, Xiaoming
- Abstract
•The uptake of uranium by tea wastes was strongly dependent on pH and ionic strength.•The maximum adsorption capacities of tea wastes was 29.412mg/g.•Adsorption data can be satisfactorily fitted by diffuse double layer model.
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- 2015
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34. Temporal-insular spreading time in temporal lobe epilepsy as a predictor of seizure outcome after temporal lobectomy
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Zhang, Xi, Zhang, Guojun, Yu, Tao, Xu, Cuiping, Zhu, Jin, Yan, Xiaoming, Ma, Kai, and Gao, Runshi
- Abstract
Insular involvement in temporal lobe epilepsy (TLE) has gradually been recognized since the widespread use of stereoelectroencephalography (SEEG). However, the correlation between insular involvement and failed temporal lobe surgery remains unclear. In this study, we analyzed the surgical outcomes of TLE patients who underwent temporal and insular SEEG recordings and explored the predictors of failed anterior temporal lobectomy (ATL) in these patients with temporal seizures.Forty-one patients who underwent ATL for drug-resistant TLE were examined using temporal and insular SEEG recordings. The clinical characteristics, SEEG data, and postoperative seizure outcomes of these patients were analyzed, and multivariate analysis was used to identify the predictors of surgical outcome.In this series, the ictal temporal discharges invaded the insula in 39 (95.1%) patients. Twenty-three (56.1%) patients were seizure-free (Engel class I) after ATL with at least 1 year follow-up. Only temporal-insular spreading time (TIST) was an independent predictor of postoperative seizure-free outcomes (P= .035). By creating receiver operating characteristic curves for TIST, 400 milliseconds was identified as the cutoff for classification. All patients were classified into 2 groups (TIST ≤ 400 milliseconds and TIST > 400 milliseconds) based on the cutoff value; the difference in seizure-free rates between the 2 groups was significant (P= .001).The very early insular involvement in TLE may be associated with poorer seizure outcomes after ATL. Our findings may be helpful for estimating the appropriate operative procedures and will be valuable for evaluating the prognosis of TLE patients with temporal-insular SEEG recordings and temporal lobectomy.
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- 2022
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35. Optimal pricing, production, and sales policies for new product under supply constraint
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Yan, Xiaoming, Liu, Ke, and Wang, Yong
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This paper considers a firm that sells a durable product with a given market potential. The purpose of the firm is to maximize its profit by determining how much capacity to install before the sales horizon, how many products to produce in accordance with the capacity, and how many products to sell by pricing. Appealing to Pontryagin maximum principle in control theory, the authors obtain the closed-forms of all optimal decisions the firm should make. Furthermore, the optimal production rate and optimal sales rate are both equal to the demand rate, which is caused by the optimal pricing policy during the whole horizon, and the optimal pricing path is increasing with the cost of installing a unit of capacity. Furthermore, numerical analysis reveals the visual impression of the relationship of the parameters.
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- 2014
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36. Hybrid UV photodetector with high photo-to-dark current ratio based on ordered TiO2nanorod arrays and polystyrene sulfate
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Zheng, WenJi, He, GaoHong, Li, XiangCun, and Yan, XiaoMing
- Abstract
Vertically aligned TiO2nanorods arrays were successfully synthesized on FTO glass by wet-chemical method. Based on polystyrene sulfate (PSS) functionalized TiO2nanorods arrays, a sandwich-structured hybrid UV photodetector was fabricated. The photo-to-dark current ratio of the device increases by more than 3 orders of magnitude with typical case, while the dark current is about 10 nA at 1 V bias. The high photoresponse together with the low dark current could probably contribute a large photocurrent and low-power application. The high performance of the hybrid material and facile low-cost fabrication of the UV detector make the devices promising for large-area UV photodetection applications.
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- 2013
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37. The Effect of Latanoprost and Brimonidine on Rabbit Subconjunctival Fibroblasts
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Lark, Kurt Karl, Pasha, Azeem Syed, Yan, Xiaoming, and Edward, Deepak P.
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Subconjunctival fibroblasts play a critical role in scarring and treatment failure in fistulizing surgery for glaucoma. The proliferation of subconjunctival fibroblasts appears to be modulated by topical glaucoma medications. This study was conducted to evaluate the effects of latanoprost and brimonidine on subconjunctival fibroblast proliferation in rabbit eyes.
- Published
- 1999
38. Movement disorders and their stereotactic surgical treatment: a retrospective study of 5126 patients at a single clinical center over 22 years
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Li, Yongjie, Qiao, Liang, Du, Tao, Li, Jianyu, Zhu, Hongwei, Hu, Yongsheng, Yu, Tao, Zhuang, Ping, Zhang, Yuqing, Zhang, Guojun, Zhang, Xiaohua, Ma, Kai, Wang, Yunpeng, Yan, Xiaoming, Ni, Duanyu, Li, Jiping, Ni, Bing, Shu, Wei, Zhang, Xi, Ren, Zhiwei, Wang, Xueyuan, Guo, Song, and Lu, Guang
- Abstract
•Parkinson’s disease is most common movement disorders that necessitates surgery.•Surgical timing is individualized and varies among different movement disorders.•DBS was the dominant surgery for movement disorders, except essential tremor.
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- 2021
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39. Mucoepidermoid Carcinoma of the Eyelid Skin
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Zhang, Cheng, Ticho, Karl E., Ticho, Benjamin H., Edward, Deepak P., Yan, Xiaoming, and Tso, Mark O. M.
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Mucoepidermoid carcinoma involving the eye or its adnexa generally arises from the conjunctiva. We describe a nodular lesion of the lower eyelid skin with histologic features consistent with low-grade mucoepidermoid carcinoma.
- Published
- 1999
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