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The development of biodegradable materials from biomass is a crucial strategy for leveraging biomass resources. A key component in this process is 2,5-bis(hydroxymethyl)furan (BHMF), a significant biomass-derived platform chemical. However, producing BHMF with high selectivity through the selective hydrogenation of 5-hydroxymethylfurfural, while avoiding the creation of unwanted byproducts, is a complex challenge. In our research, we have developed a novel catalyst featuring a magnetic core. This catalyst, which consists of platinum loaded onto a graphene-like shell, has been applied to the catalytic hydrogenation of HMF in an aqueous environment. Under the optimized conditions of 373 K, 3 MPa H2, and 1 h reaction time, a BHMF yield exceeding 99% was achieved. This method presents a promising and effective approach for the high-value conversion of biomass waste into polymer materials and pharmaceutical chemicals. [ABSTRACT FROM AUTHOR]

Sustainable battery recycling is essential for achieving resource conservation and alleviating environmental issues. Many open/closed-loop strategies for critical metal recycling or direct recovery aim at a single component, and the reuse of mixed cathode materials is a significant challenge. To address this barrier, here we propose an upcycling strategy for spent LiFePO4 and Mn-rich cathodes by structural design and transition metal replacement, for which uses a green deep eutectic solvent to regenerate a high-voltage polyanionic cathode material. This process ensures the complete recycling of all the elements in mixed cathodes and the deep eutectic solvent can be reused. The regenerated LiFe0.5Mn0.5PO4 has an increased mean voltage (3.68 V versus Li/Li+) and energy density (559 Wh kg–1) compared with a commercial LiFePO4 (3.38 V and 524 Wh kg–1). The proposed upcycling strategy can expand at a gram-grade scale and was also applicable for LiFe0.5Mn0.5PO4 recovery, thus achieving a closed-loop recycling between the mixed spent cathodes and the next generation cathode materials. Techno-economic analysis shows that this strategy has potentially high environmental and economic benefits, while providing a sustainable approach for the value-added utilization of waste battery materials. Direct recycling of critical battery materials bring promise but a challenge for the mixed cathode chemistries. Here, the authors report a sustainable upcycling approach, transforming degraded LiFePO4 and Mn-rich cathodes into a high-voltage polyanionic material with an increased energy density and economic value. [ABSTRACT FROM AUTHOR]

To obtain large exciting force for elliptical vibrating screen, a new three-exciter vibration system with two elastic coupling coaxial exciters is proposed. For studying the vibration characteristics and synchronization capability of the system, the Lagrange equation is firstly introduced to establish the dynamic model of the system. Then, the steady-state responses of the system are determined. Subsequently, the synchronous condition of the system is discussed by means of the averaged small parameter method and existence conditions of solutions for the synchronization torque balance equations of the vibration system, the synchronous stability condition of the system is established by the stability of the solution of the torque balance equation, and some numerical calculations, computer simulations and vibration experiments are performed to verify the correctness of the theoretical derivation. It can be found that, the ideal synchronization of two elastic coupling coaxial exciters can be achieved by selecting a torsion spring with appropriate stiffness, the two coaxial exciters can realize in-phase synchronization even if power source of either of the two motors is cut off, and the average phase difference angles are very close to the situation when all three motors are powered on. By using the mechanical model and synchronous theory proposed in this paper, a double-layer elliptical shale shaker was developed and has been successfully applied to oil drilling engineering. [ABSTRACT FROM AUTHOR]

TianQin and LISA are space-based laser interferometer gravitational wave (GW) detectors planned to be launched in the mid-2030s. Both detectors will detect low-frequency GWs around 10−2 Hz; however, TianQin is more sensitive to frequencies above this common sweet-spot while LISA is more sensitive to frequencies below 10−2 Hz. Therefore, TianQin and LISA will be able to detect the same sources but with different accuracy depending on the source and its parameters. We consider some of the most important astrophysical sources—massive black hole binaries, stellar-mass black hole binaries, double white dwarfs, extreme mass ratio inspirals, light and heavy intermediate mass ratio inspirals, as well as the stochastic gravitational background of astrophysical origin—that TianQin and LISA will be able to detect. For each of these sources, we analyze how far they can be detected (detection distance) and how well their parameters can be measured (detection accuracy) using a Fisher Matrix analysis. We compare the results obtained by the three detection scenarios (TianQin alone, LISA alone, and joint detection by LISA and TianQin) highlighting the gains from joint detection as well as the contribution of TianQin and LISA to a combined study of astrophysical sources. In particular, we consider the different orientations, lifetimes, and duty cycles of the two detectors to explore how they can give a more complete picture when working together. [ABSTRACT FROM AUTHOR]

In the process of network-based data flow transmission for various applications of information services, there are some problems, such as limited bandwidth and unclear priority level of business data, which affect the end-to-end reliable transmission efficiency because the system cannot perceive the link state. Traditional parallel link redundancy schemes have not fundamentally solved the problems of invulnerability and reliability. On the basis of sorting out the demand of service data flow transmission, this paper proposes a performance verification method of data flow packet scheduling algorithm based on QoS to solve the problems of network delay and congestion, and explores a reliable end-to-end service data flow transmission mode. [ABSTRACT FROM AUTHOR]

Perovskite solar cells with the formula FA1−xCsxPbI3, where FA is formamidinium, provide an attractive option for integrating high efficiency, durable stability and compatibility with scaled-up fabrication. Despite the incorporation of Cs cations, which could potentially enable a perfect perovskite lattice1,2, the compositional inhomogeneity caused by A-site cation segregation is likely to be detrimental to the photovoltaic performance of the solar cells3,4. Here we visualized the out-of-plane compositional inhomogeneity along the vertical direction across perovskite films and identified the underlying reasons for the inhomogeneity and its potential impact for devices. We devised a strategy using 1-(phenylsulfonyl)pyrrole to homogenize the distribution of cation composition in perovskite films. The resultant p–i–n devices yielded a certified steady-state photon-to-electron conversion efficiency of 25.2% and durable stability.We added out-of-plane cations to homogenize the distribution of cations in perovskite films, resulting in a solar cell with improved efficiency and stability. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal is believed to be the "Holy Grail" among all anode materials for next-generation Li-based batteries due to its high theoretical specific capacity (3860 mAh/g) and lowest redox potential (−3.04 V). Disappointingly, uncontrolled dendrite formation and "hostless" deposition impede its further development. It is well accepted that the construction of three-dimensional (3D) composite Li metal anode could tackle the above problems to some extent by reducing local current density and maintaining electrode volume during cycling. However, most strategies to build 3D composite Li metal anode require either electrodeposition or melt-infusion process. In spite of their effectiveness, these procedures bring multiple complex processing steps, high temperature, and harsh experimental conditions which cannot meet the actual production demand in consideration of cost and safety. Under this condition, a novel method to construct 3D composite anode via simple mechanical modification has been recently proposed which does not involve harsh conditions, fussy procedures, or fancy equipment. In this mini review, a systematic and in-depth investigation of this mechanical deformation technique to build 3D composite Li metal anode is provided. First, by summarizing a number of recent studies, different mechanical modification approaches are classified clearly according to their specific procedures. Then, the effect of each individual mechanical modification approach and its working mechanisms is reviewed. Afterwards, the merits and limits of different approaches are compared. Finally, a general summary and perspective on construction strategies for next-generation 3D composite Li anode are presented. [ABSTRACT FROM AUTHOR]

In permafrost regions, permafrost degradation negatively jeopardizes the security of infrastructures, in which large pipeline deformation will happen owing to settlement disaster. Under the scenarios of climate warming and positive oil temperature, how to effectively alleviate permafrost degradation is a critical issue. Numerical evaluation is performed on the influences of the protective measures, which include insulation layer, two-phase closed thermosyphon (TPCT), and combined measures based on the thermo-mechanical coupled model. The numerical results show that most of the heat released from the warm-oil pipeline to soil is isolated by insulation layer, and the expected insulation thickness is 8 cm. On the other hand, TPCT can effectively cool underlying permafrost inhibiting the thaw bulb from growing over time by air-TPCT-soil heat transfer. The combination of insulation layer and TPCT has significantly reduced the pipe stress by more than 60% within 30 years, in which the maximum stress of pipeline is consistently lower than the yield stress. Consequently, the combined measure should be considered for application to ensure pipeline safety in permafrost. [ABSTRACT FROM AUTHOR]

Severe color casts, low contrast, and blur of underwater images caused by light absorption and scattering result in a challenging task for exploring underwater environments. In this paper, we propose a novel joint wavelength compensation and dehazing network (JWCDN) to remove the degradation effects caused by light absorption and scattering. The joint learning framework is based on an improved underwater image formation model that takes into account the vertical (water surface-object path) and horizontal (object-camera path) effects of light propagation in water. By embedding the underwater image formation model into a generative adversarial network, we can jointly estimate the transmission map, wavelength attenuation, and background light via different network modules, and use the underwater image formation model to recover degraded underwater images. To further improve the recovered image, we use an edge-preserving network module to enhance the detail of the recovered image. Moreover, to train the proposed network, we present an effective underwater image synthesis method that generates underwater images using the optical attenuation coefficients of different water types. The synthesis method can simulate the color, contrast, and blur of different underwater imaging environments. Extensive experiments on synthetic and real-world underwater images demonstrate that the proposed method yields comparable or better results on both subjective and objective assessments, compared with several state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Purpose: Although systolic blood pressure (SBP) is associated with acute renal injury (AKI), the relationship between baseline SBP and prognosis in critically ill patients with AKI is unclear. We aimed to assess the linearity and profile of the relationship between SBP at intensive care unit (ICU) admission and in-hospital mortality in these patients. Methods: Data of AKI patients in the ICU settings were extracted from the Medical Information Mart for Intensive Care III database. The association between seven SBP categories (< 100, 100–109, 110–119, 120–129, 130–139, 140–149, and ≥ 150 mmHg) and all-cause in-hospital mortality was assessed by Cox proportional hazard models. Restricted cubic spline analysis for the multivariate Cox model was performed to explore the shape of the relationship between SBP and mortality. Results: A total of 24,202 patients with AKI were included in this study. A typically U-shaped relationship was found between SBP at admission and in-hospital mortality. Among all SBP categories, the lowest risk of death was observed in patients with SBP around 110–119 mmHg, whereas the highest was noted in patients with extremely low SBP (< 100 mmHg), followed by those with extremely high SBP (≥ 150 mmHg). SBP showed a significant interaction with vasopressor use and AKI stage in relation to the risk of in-hospital mortality. Conclusions: SBP upon admission showed a non-linear association with all-cause in-hospital mortality in critically ill patients with AKI. Patients with low or high SBP show an increased risk of mortality compared to patients with normal SBP. [ABSTRACT FROM AUTHOR]

Sympathetic axonal sprouting into dorsal root ganglia is a major phenomenon implicated in neuropathic pain, and sympathetic ganglia blockage may relieve some intractable chronic pain in animal pain models and clinical conditions. These suggest that sympathetic ganglia participated in the maintenance of chronic pain. However, the molecular mechanism underlying sympathetic ganglia-mediated chronic pain is not clear. Here, we found that spared nerve injury treatment upregulated the expression of ADAMTS4 and AP-2α protein and mRNA in the noradrenergic neurons of sympathetic ganglia during neuropathic pain maintenance. Knockdown the ADAMTS4 or AP-2α by injecting specific retro scAAV-TH (Tyrosine Hydroxylase)-shRNA ameliorated the mechanical allodynia induced by spared nerve injury on day 21 and 28. Furthermore, chromatin immunoprecipitation and coimmunoprecipitation assays found that spared nerve injury increased the recruitment of AP-2α to the ADAMTS4 gene promoter, the interaction between AP-2α and histone acetyltransferase p300 and the histone H4 acetylation on day 28. Finally, knockdown the AP-2α reduced the acetylation of H4 on the promoter region of ADAMTS4 gene and suppressed the increase of ADAMTS4 expression induced by spared nerve injury. Together, these results suggested that the enhanced interaction between AP-2α and p300 mediated the epigenetic upregulation of ADAMTS4 in sympathetic ganglia noradrenergic neurons, which contributed to the maintenance of spared nerve injury induced neuropathic pain. [ABSTRACT FROM AUTHOR]

Neural response generation can automatically produce replies for open-domain dialogue systems without hand-crafted rules or templates. Current studies follow a non-context-adaptive paradigm that employs a single response generator to deal with all dialogues. However, as a dialogue progresses, its textual characteristics (e.g., context length, information volume, involving topics) are changing, so are the issues challenging its response generation. Non-context-adaptive response generators are inflexible and may fail to achieve globally good performance without considering the differences existing among dialogues. In this paper, we propose a novel framework named as C ontext-A daptive R esponse G eneration (CARG), which assembles two different response generators to respectively handle long and short dialogues. Specifically, given a dialogue, CARG first classifies it into short or long types according to the number of its containing utterances. For a short dialogue, CARG employs a sequential reader (SR) to concatenates all utterances into a sequence aiming to construct the dialogue context by limited semantics. For a long dialogue where irrelevant noises and relevant contexts both exist, CARG uses a jumping reader (JR) to generate the response, which treats the latest utterance as the anchor and further performs selective context utilization under its guidance. We introduce ensemble learning strategy to conduct the training and testing of CARG. Extensive experimental results on two benchmark chat corpora show that the proposed CARG framework can outperform various competitive baselines, validating its effectiveness on response generation. [ABSTRACT FROM AUTHOR]

Shape control of mesoporous carbon microparticles (MCMPs) is of critical importance; in particular, asymmetric shapes that can yield unique properties have attracted significant attention. However, the tailored synthesis of asymmetric MCMPs with ordered structures remains challenging. Herein, we report a facile route to prepare asymmetric MCMPs by neutral interface-guided 3D-confined self-assembly (3D-CSA) of block copolymer/homopolymer (BCP/hP) blends, followed by a self-templated selective direct carbonization strategy. BCP/hP Janus microparticles with ordered hierarchical mesostructures were prepared with emulsion solvent evaporation-induced 3D-CSA. The continuous phase of BCP domains was then crosslinked. Composite asymmetric MCMPs are successfully generated after selective carbonization of the crosslinked continuous phase. This method allows tuning the shape of MCMPs easily by varying the blending ratio of BCP/hP. The composite asymmetric MCMPs combine the advantages of asymmetric shape, ordered structure, high specific surface area, chemical inertness and thermal stability and could provide great possibilities for applications in catalysis, drug delivery, energy conversion and storage. [ABSTRACT FROM AUTHOR]

Land use is an effective way to reduce carbon emission in the recycling process of municipal sludge compost; meanwhile, heavy metals (HMs) in the sludge can be phytoextracted by ornamental plants. As an eco-friendly soil amendment, citric acid (CA) has been reported to be of great potential aid to phytoremediation, and its effect on ryegrass (Lolium perenne L.) extraction of HMs (Zn, Ni, Pb, Cu, and Cd) from municipal sewage sludge compost-amended (MSSC) soils has been investigated through pot experiments in the study. The growth of ryegrass was significantly promoted under 2 and 4 mmol kg−1 CA treatments. The concentrations of HMs in MSSC soil after 45-day planting were significantly reduced ( p < 0.05 ), and they were further reduced except for Cu while CA treated. The acid-extractable fraction of HMs in the soil was increased significantly as CA treated, and further improvement could be found when CA dose increased, which was due to the decreased soil pH and the complexation of CA with metal ions. The phytoremediation factor (PRF) was proposed to assess the phytoremediation efficiency, which was obtained as a ratio of the product of the biomass and metal concentration of plant shoot between the CA-treated group and the control group. When the CA dose was 6 mmol kg−1, the average PRF of five heavy metals reached 2.29, and Cd was the highest (3.72), demonstrating that CA had great promotion on phytoremediation of heavy metals. This study made a contribution to the research of phytoremediation in sludge land use by demonstrating ryegrass as an ideal bioaccumulator for heavy metals, especially for Cd. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Rib fracture is closely related to thoracic injury with high morbidity and mortality. This study aimed to investigate the clinical effect of Zhang ZhiFei (ZZF) zoning method on the selection of incision and approach in minimally invasive surgery for rib fracture. Methods: A total of 110 patients with rib fractures from July 2017 to July 2019 were enrolled in the study. Preoperative computed tomography and three-dimensional reconstruction of ribs was performed. Then, the rib fractures to be surgically fixed were divided into costal cartilage zone, chest zone, lateral costal zone, high posterior costal zone, low posterior costal subscapular zone, and low posterior costal paraspinal zone, which was called ZZF zoning method. Rib fractures in each zone had unique minimally invasive incision approach, and the open reduction and internal fixation of rib fracture was performed under minimally invasive surgery of corresponding small incision. Results: The average incision length and number of incisions of the 110 patients were 6.2 cm and 1.3, respectively. The average number of internal fixation was 5.3 and the average operation time was 82 min. The postoperative fracture end was well aligned. After 3 months of follow-up, no internal fixation was displaced or detached. Conclusion: Based on the anatomical characteristics of different zones of the chest wall, ZZF zoning method provides a new idea and reference for the selection of incision and approach in minimally invasive internal fixation for rib fracture. [ABSTRACT FROM AUTHOR]

In this work, g-C3N4/melem nanorods hybrids were synthesized via a rapid cooling process with H2SO4-assisted treatments of bulk g-C3N4. The results show that post treatment of pristine g-C3N4 using concentrated H2SO4 can produce a hybrid crystal structure containing both melem and g-C3N4. The melem nanorods were formed based on H2SO4 exfoliation, regrowth process and nanoplates roll-up mechanism through a rapid cooling process. The g-C3N4/melem nanorods hybrids exhibited efficient degradation of methyl orange and the efficiency was nearly 100% in 80 min, which presented much better than bulk g-C3N4 (giving a degradation efficiency of 67% in 80 min). The enhanced photocatalytic performance of g-C3N4/melem nanorods hybrids mainly originates from the synergistic effect of g-C3N4 and melem, which the g-C3N4/melem hybrids can improving the efficiency of photogenerated charge separation of g-C3N4. This study contributes towards an effective strategy for optimizing the crystalline structure and nanostructure of g-C3N4/melem hybrids to enhanced g-C3N4 photodegradation activity. [ABSTRACT FROM AUTHOR]

The construction of digital museum is the inevitable trend of the development of museum cause. At present, there are some problems in the construction of digital museum in China, such as backward concept, low overall level, lack of funds and talents. Digital museum is a museum that uses digital and network technology to present the functions of physical museum on the network in a digital way. It includes three parts: the on-site digital display system of the museum exhibition hall, the museum business management system based on network digital technology and the network platform display system. This paper designs and implements a new intelligent digital museum system based on the hybrid reality technology. Compared with the existing digital museum navigation mode, the system gets rid of the tedious way of navigation, provides tourists with more diverse and realistic cultural relics information, and makes the human–computer interaction more humanized. The museum construction in the future will continue to be digital, networked and intelligent, which provides a good practice platform and a broad development world for the improvement and application of new technologies. Besides, the software-driven data collection and analysis models are combined for the systematic performance improvement of the model. The comparison experiment has shown that the proposed model is efficient. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electrochemical oxygen reduction could proceed via either 4e−-pathway toward maximum chemical-to-electric energy conversion or 2e−-pathway toward onsite H2O2 production. Bulk Pt catalysts are known as the best monometallic materials catalyzing O2-to-H2O conversion, however, controversies on the reduction product selectivity are noted for atomic dispersed Pt catalysts. Here, we prepare a series of carbon supported Pt single atom catalyst with varied neighboring dopants and Pt site densities to investigate the local coordination environment effect on branching oxygen reduction pathway. Manipulation of 2e− or 4e− reduction pathways is demonstrated through modification of the Pt coordination environment from Pt-C to Pt-N-C and Pt-S-C, giving rise to a controlled H2O2 selectivity from 23.3% to 81.4% and a turnover frequency ratio of H2O2/H2O from 0.30 to 2.67 at 0.4 V versus reversible hydrogen electrode. Energetic analysis suggests both 2e− and 4e− pathways share a common intermediate of *OOH, Pt-C motif favors its dissociative reduction while Pt-S and Pt-N motifs prefer its direct protonation into H2O2. By taking the Pt-N-C catalyst as a stereotype, we further demonstrate that the maximum H2O2 selectivity can be manipulated from 70 to 20% with increasing Pt site density, providing hints for regulating the stepwise oxygen reduction in different application scenarios. Controlling O2 reduction pathways can help optimize catalytic activity and product selectivity. Here the authors report facile manipulation of 2e‒ /4e‒ pathways on Pt-coordinated motifs by varying the Pt site density or the coordination environment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Zinc silicate is a promising microwave dielectric material because of its excellent dielectric properties, i.e., low dielectric permittivity (εr) and high quality factor (Q × f). CuxZn1.8-xSiO3.8 ceramics (0 ≤ x ≤ 0.4 with a step of 0.1) were fabricated using a conventional solid-state process, and the Zn-deficient approach was employed to suppress the formation of secondary phases. The X-ray diffraction reveals that Cu2+ doping does not alter the main crystal structure of Zn2SiO4 but the secondary phase of CuO and SiO2 is formed when Cu content exceeds solid solubility. Also, the addition of Cu2+ ions widens the sintering temperature zone, and then reducing sintering temperature by nearly 300 °C. The addition of CuO changes the microstructure of the crystal, but redundant CuO forms the secondary phase and affects the dielectric permittivity of the material. On the other hand, the dielectric permittivity has a linear relationship with the temperature stability coefficient. At x = 0.1 and T = 1010 °C, the quality factor of Cu0.1Zn1.7SiO3.8 ceramics reaches a maximum value of 54,128 GHz, while the dielectric properties also attain the optimal level: εr = 6.70 and τf = − 29.22 ppm/ °C. It is worth emphasizing that the as-fabricated ceramics can be co-fired with copper electrodes, rendering promise in wireless communication technology. [ABSTRACT FROM AUTHOR]

Extreme climatic events such as drought and high temperatures are frequently occurring under the global climate change scenarios causing severe threats to crop yield. Several studies have used individual events, e.g., meteorological drought (dry event), high temperatures (hot event), or compound dry–hot events as predictors of agricultural drought severity. However, only a few studies considered the situation when at least one dry event or hot event appeared. Moreover, the ability to depict drought phenomena, in terms of duration and severity, with the same drought index for different time scales was often inconsistent. This study adopted the meta-Gaussian model (MG) to predict agricultural drought severity for the crops and vegetation growing seasons (from April to September) from the year 1948 to 2014 in China by using two predictors, namely, standardized dry or hot events index (SDHEI) and joint soil moisture deficit index (JSDI). The SDHEI was built based on monthly precipitation and daily temperature, and the JSDI was calculated by combining 1-, 3-, 6-, 9-, and 12-month standardized soil moisture index (SSI) based on monthly root zone soil moisture. The prediction performance of the MG was assessed by employing the Brier skill score (BSS), Nash–Sutcliffe efficiency coefficient (NSE), and root mean square error (RMSE). The severe agricultural drought in the months of April–September of 2010 in China was used as a case study. A visual comparison of this event indicated that the lead JSDI predictions for 1–3 months showed a resembled behavioral pattern with corresponding historical observations for most of the areas of China; however, it had some disagreements in the spatial extent and severity of the agricultural drought in some of the regions. The MG had a great performance with BSS > 0.4, NSE > 0.6, and RMSE < 0.6 for the 1-month lead prediction of JSDI in most of the study areas; however, it turned to be weaker in some regions for the 3-month lead prediction. Overall, the prediction performance of MG in April–June outperformed the same in July–September under the same lead prediction of JSDI. The outcomes of this study might provide scientific guidance for agricultural drought monitoring, early warning, and drought decision-making in China or other countries. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) represent efficient energy storage technology that can help to alleviate fossil fuel-based CO2 emissions. Presently, LIBs are being applied extensively in consumer electronics and electric vehicles, but because of limited resources, there is an urgent need for spent LIB recycling technologies. The complexity of LIBs, especially the electrode part, makes it difficult to achieve precision separations for each single component from the used electrode with low emissions. Herein, we propose a three-step treatment for the separation of cathode components. In detail, detaching of the current collector from the cathode is accomplished by the solvent method, which was found to be an ideal strategy compared with previous reports. Then, a thermal treatment is used to remove the polymer binder in the second step because we demonstrated that it is challenging to separate polyvinylidene fluoride (PVDF) from other cathode components by dissolution with N-methylpyrrolidone. The separation efficiency between the active material and conductive carbon by the polymer solution in the third step showed reasonably good results. We anticipate this work will serve as an important reference for the separation of each single electrode component in both laboratory- and industrial-scale applications. Separation of binder and development of novel binders, which can be easily recycled for sustainable LIBs, are fruitful areas for further research. [ABSTRACT FROM AUTHOR]

The relationships of cooling rate with microstructure and thermal conductivity of vermicular graphite cast iron (VGI) cylinder block were studied, which are important for design and optimization of the casting process of VGI cylinder blocks. Cooling rates at different positions in the cylinder block were calculated based on the cooling curves recorded with a solidification simulation software. The metallographic structure and thermal conductivity were observed and measured using optical microscopy (OM), scanning electrical microscopy (SEM) and laser flash diffusivity apparatus, respectively. The effects of the cooling rate on the vermicularity, total and average areas of all graphite particles, and the pearlite fraction in the VGI cylinder block were investigated. It is found that the vermicularity changes in parabola trend with the increase of cooling rate. The total area of graphite particles and the cooling rate at eutectoid stage can be used to predict pearlite fraction well. Moreover, it is found that the thermal conductivity at room temperature is determined by the average area of graphite particles and pearlite fraction when the range of vermicularity is from 80% to 93%. Finally, the quantitative models are established to calculate the vermicularity, pearlite fraction, and thermal conductivity of the VGI cylinder block. [ABSTRACT FROM AUTHOR]

Zn2SiO4 ceramics are important candidates for microwave dielectric materials applied in wireless communication. However, the appearance of the second phase and stomatal impurity affect the microwave dielectric properties. In this work, Zn2SiO4 ceramics were prepared by the conventional solid-state process under different temperatures according to Zn-deficient formula to suppress the formation of secondary phase. X-ray diffraction showed peaks that coincide with those of Zn2SiO4 PDF card standard without secondary phase. Scanning electron microscopy revealed that there were uniform crystal grains at 1300 °C, and larger grains sizes yielded smaller pore gaps. The dielectric properties of Zn1.8SiO3.8 ceramics sintered at 1300 °C were estimated to εr = 6.451, Q*f = 102,807 GHz, and τf = -32 ppm/°C.. In summary, Zn1.8SiO3.8 ceramics had potential applications in wireless communication technology due to their excellent dielectric property. [ABSTRACT FROM AUTHOR]

The discrete element method (DEM) is used according to the discreteness of the gravel layer to analysis the gravel particle. This paper presents simulations of tri-axial experiment tests and settlement of gravel layer. The stress-strain curves of gravel layer were analysed with different confining pressure through tri-axial numerical test, and the effect with different particle parameters and confining pressures was analysed. The numerical model of gravel layer after the excavation was established by the DEM to statistically analyse the settlement of gravel layer. The analyses results show that confining pressure corresponds to axial pressure that be destroyed of gravel particle model. The static friction coefficient has little effect on the failure of the tri-axial confining experimental model. The experiment model with various particle sizes need higher axial stress that be destroyed than the same particle size. During the collapse of the gravel stratum, the gravels are closer to the top of the hole which have a larger shift of settlement and a faster sedimentation rate. If the gravel are further away from top of the hole which have a smaller shift of settlement and slower sedimentation rate. The settlement of gravel causes the forces variation in all directions. [ABSTRACT FROM AUTHOR]

With the demand for higher energy density and smaller size lithium-ion batteries (LIBs), the development of high specific capacity active materials and the reduction of the usage of inactive materials are the main directions. Herein, a universal method is developed for binder-free electrodes for excellent stable LIBs by rolling the electrospun membrane directly onto the commercial current collector. The rolling process only makes the fiber web denser without changing the fiber structure, and the fiber web still maintains a porous structure. This strategy significantly improves the structural stability of the membrane compared to the direct carbonized electrospun membrane. Moreover, this method is suitable for a variety of polymerizable adhesive polymers, and each polymer can be composited with different polymers, inorganic salts, etc. The electrode prepared by this method can be stably cycled for more than 2000 cycles at a current density of 2500 mA g−1. This study provides a cost-effective and versatile strategy to design the LIB electrode with high energy density and stability for experimental research and practical application. [ABSTRACT FROM AUTHOR]

Dendrobium officinale is a rare and endangered perennial herb in China, which have been used in preparing Chinese tonic medicine for hundreds of years. The severe shortage of this herb and high price have caused that many similar plants were processed as an adulterant and it became difficult to distinguish genuine D. officinale by traditional authentication methods. A sensitive, convenient, and specific method for rapid identification of D. officinale is urgently needed. In the present study, 3D front-face fluorescence technique merged with Independent Component Analysis was used to get the "pure" independent fluorescence signals. The overall 3D-FFF spectra were decomposed into seven independent components (IC). To distinguish D. officinale from other species, IC1 and IC4 were chosen as fluorescence markers and the fluorescence intensity (FI) value at 340 nm/ 442 nm (excitation /emission wavelength) of IC1and 315 nm/ 468 nm of IC4 were used to build a linear model for identifying D. officinale successfully. Compared with other Dendrobium species, D. officinale showed much higher FI1 and FI4 value which is a direct criterion for identification. Meanwhile, even though the FI values of D. officinale may fluctuate due to the difference of growing conditions, the relation between FI1 and FI4 amazingly always fit the linear model constructed (FI4 = 9.9046 + 0.6119FI1, R2 = 0.9811). The linear model is an important finding and specific for D. officinale. Based on the FI value and the goodness of fit in the linear model, D. officinale can be identified quickly. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIB) as energy supply and storage systems have been widely used in electronics, electric vehicles, and utility grids. However, there is an increasing demand to enhance the energy density of LIB. Therefore, the development of new electrode materials with high energy density becomes significant. Although many novel materials have been discovered, issues remain as (1) the weak interaction and interface problem between the binder and the active material (metal oxide, Si, Li, S, etc.), (2) large volume change, (3) low ion/electron conductivity, and (4) self-aggregation of active materials during charge and discharge processes. Currently, the binder-free electrode serves as a promising candidate to address the issues above. Firstly, the interface problem of the binder and active materials can be solved by fixing the active material directly to the conductive substrate. Secondly, the large volume expansion of active materials can be accommodated by the porosity of the binder-free electrode. Thirdly, the ion and electron conductivity can be enhanced by the close contact between the conductive substrate and the active material. Therefore, the binder-free electrode generally exhibits excellent electrochemical performances. The traditional manufacture process contains electrochemically inactive binders and conductive materials, which reduces the specific capacity and energy density of the active materials. When the binder and the conductive material are eliminated, the energy density of the battery can be largely improved. This review presents the preparation, application, and outlook of binder-free electrodes. First, different conductive substrates are introduced, which serve as carriers for the active materials. It is followed by the binder-free electrode fabrication method from the perspectives of chemistry, physics, and electricity. Subsequently, the application of the binder-free electrode in the field of the flexible battery is presented. Finally, the outlook in terms of these processing methods and the applications are provided. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are currently the most important energy storage system. Separators in the battery play a critical role in terms of the rate capability, cycle life, and safe operation. However, commercial separators exhibit poor electrolyte wettability and limited safety. It is also extremely important to eliminate the hazardous small molecules (e.g., H2O and HF) inside the battery to enhance the service life. Herein, a functionalized poly(vinylidene fluoride-co-hexafluoropropylene)@polyacrylonitrile (PVDF-HFP@PAN) separator modified by 4-Å molecular sieves (MS) was fabricated by hydrothermal method for LIBs. MS@PVDF-HFP@PAN separator exhibits high thermal stability and carbonate electrolyte wettability. In addition, it can lower the moisture value in the battery system to 13 ppm, which significantly improves the electrolyte quality. When the current density increased from 0.2 to 5 C, the discharging capacity of the cell with MS@PVDF-HFP@PAN declines from 177.6 to 143.2 mAh g−1, demonstrating an excellent capacity retention of 80.6%. The discharge capacity retention of NMC622 half-cell with MS@PVDF-HFP@PAN after 100 cycles is 98.6% of its initial discharge capacity, which is higher than that of a cell with the Celgard 2400 separator (91.9%). [ABSTRACT FROM AUTHOR]

The prevalence of allergic rhinitis (AR) is increasing worldwide. However, the current systems used to measure levels of immunoglobulin E (IgE) in sera are associated with several disadvantages that limit their further application. Consequently, there is a need to develop novel highly sensitive strategies that can rapidly detect IgE in a quantitative manner. The development of such systems will significantly enhance our ability to diagnose, treat, and even prevent AR. Herein, we describe our experience of using quantum dot-based lateral flow immunoassay (QD-LFIA), combined with a portable fluorescence immunoassay chip detector (PFICD), to detect serum-specific IgE against Dermatophagoides pteronyssinus (Der-p) and Dermatophagoides farinae (Der-f), two common mite allergens in China. Our data showed that our system could detect serum-specific levels of IgE against Der-p and Der-f as low as 0.093 IU/mL and 0.087 IU/mL, respectively. We also established a standard curve to determine serum-specific IgE concentrations that correlated well with the clinical BioIC microfluidics system. The sensitivity of our assay was 96.7% for Der-p and 95.5% for Der-f, while the specificity was 87.2% for Der-p and 85.3% for Der-f. Collectively, our results demonstrate that QD-LFIA is a reliable system that could be applied to detect serum-specific IgE in accordance with clinical demands. This QD-LFIA strategy can be applied at home, in hospitals, and in pharmacies, with reduced costs and time requirements when compared with existing techniques. In the future, this system could be developed to detect other types of allergens and in different types of samples (for example, whole blood). [ABSTRACT FROM AUTHOR]

Understanding the anisotropic behavior of jointed rock mass subjected to various confining pressures is crucial for designing, evaluating the performance and assessing the stability of rock engineering structures. We report here our numerical investigation of the response of stress-dependent anisotropy of a jointed rock mass sourced from the weakly weathered zone of the water inlet slope of the Xiaowan Hydropower Station, China. The finite element method (FEM) that incorporates material heterogeneity and joint network was utilized. Two-dimensional models were established based on the Monte-Carlo method and loaded in different rotational angles with changing confining pressures at the representative elementary volume (REV) size (14 × 14 m). The stress–strain behaviors, failure patterns, deformation modulus and peak strength of the REV models exhibited noticeable stress dependency and directionality. The cohesive strength was anisotropic, whereas there was only an insignificant change in the friction angle with changes in the rotational angle. The effect of confining pressure on the anisotropy index of the deformation modulus was negligible, while the anisotropy index of peak strength decreased gradually with confining pressure. Based on these results, we conclude that stress conditions need to be considered for accurate prediction of the mechanical behavior of a jointed rock mass. [ABSTRACT FROM AUTHOR]

In this paper, a novel enhanced tube with slot dimples aiming to improve heat transfer have been put forward. The flow and heat transfer characteristics of the enhanced tube with slot dimples (ETSD) were numerically analysed and compared with spherical/elliptical dimples. The distributions of temperature, velocity, pressure, Nusselt number and streamlines were carried out to describe the mechanism of heat transfer and fluid flow. Additionally, the effects of dimple depth, length and axis ratios on turbulent fluid flow and heat transfer performances were also being studied in details. It is found that the enhanced tube with slot dimples have an advantage for augmented heat transfer rate compared with the spherical/elliptical dimple tube due to the slot dimples generated greater swirling flow, better fluid mixing, and greater flow blockage. In addition, the slot dimples destroyed the boundary layer, intense flow mixing and formed periodic impinge flows, thus significant improved of thermal–hydraulic performance. The Nu/Nu0 and f/f0 for ETSD increases with the increasing of dimples depth, and decreases with increasing of pitch. The ETSD with D = 1.5 mm, P = 30 mm, R = 2.33 and Re = 5000 provided the largest PEC value about 2.02 in all the case. [ABSTRACT FROM AUTHOR]

In this paper, a new method and manufacture apparatus for producing enhanced tube with dimples and protrusions (ETDP) have been proposed for the first time. The main objective of the present work is to investigate the mechanical responses of the smooth tube in extruding process. Additionally, the effects of extrusion depth, extrusion spacing, teeth radius, and tube wall thickness on deformation, stress, plastic strain, and extrusion force of ETDP were also investigated. From this investigation, it found that the dimples formed due to the smooth tube protruded, and protrusions formed due to the smooth tube dented. The maximum deformation, stress, and plastic strain at protrusion regions are larger than dimples. Among the investigated different extruding parameters, it found that the stress, deformation, and plastic strain increase with the increasing of D and δ. However, it increases with the decreases of extrusion P. In addition, R has no obvious effect on mechanical behavior of ETDP at current arrangement. The results can help to understand the forming process parameters and improve the forming quality. [ABSTRACT FROM AUTHOR]

Aims: Abscisic acid (ABA) has been shown to prime rice seedlings for enhanced tolerance to alkaline stress under both greenhouse and field conditions. This study aimed to understand the mechanism of the ABA priming effect. Methods: Rice seedlings were grown hydroponically and pretreated with ABA (10 μM) for 24 h, and then subjected to alkaline stress simulated by 15 mM Na2CO3 solution (pH 10.87). Paraquat (2.5–25 μM) was used as an intracellular generator of reactive oxygen species (ROS). Results: Compared to the control treatment, pretreatment with ABA significantly mitigated root damage and improved the survival rate of rice seedlings under alkaline conditions. Furthermore, ABA pretreatment increased the antioxidant enzyme activities of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase, and reduced the alkalinity- and paraquat-induced ROS accumulation (O2·- and H2O2) and seedling injury and mortality. In addition, the expression of the ABA-responsive genes SalT and OsWsi18, as well as the stress tolerance-related genes OsJRL, OsPEX11, OsNAC9, OsAKT1 and OsHKT1, was superinduced by ABA pretreatment under alkaline conditions. Conclusions: ABA priming enhances tolerance to alkaline stress by upregulating the antioxidant defense system and stress tolerance-related genes in the roots of rice seedlings. [ABSTRACT FROM AUTHOR]

Photoluminescent CuIn(SexS1 − x)2 (CISeS) nanocrystals (NCs) have been synthesized utilizing copper iodide (CuI) and indium acetate (In(Ac)3) as metal cation precursors, Se powder and n-dodecanethiol (DDT) as selenide and sulfur source, combined with oleylamine and n-dodecanethiol as coordinate ligands at a moderate reaction temperature of 200 °C. The obtained CISeS NCs consisted of a gradient composition that the content of selenide increased from the nuclei to the surface. With the growth of NCs, they exhibited a tunable photoluminescent emission ranging from 722 to 830 nm which was size- and composition-dependent. The photoluminescent quantum yield of the NCs could be further enhanced from 1.2 to 40.7% after ZnS coating due to the formation of ZnCuIn(SexS1 − x)2/ZnS (ZnCISeS/ZnS) core-shell structures with the alloyed core. The photoluminescence emission mechanisms of CISeS NCs indicated that the gradient composition structure of CISeS led to a gradient energy level of its conduction band (CB)/valence band (VB), resulting in the charge transfer from the nuclei to the surface through the quantized CB/VB. This transfer process has quenched fluorescence emission arising from the quantized CB/VB and defect states located in the nuclei, such as irradiation relaxation between quantized CB and VCu′. This mechanism could illuminate why the indium-rich CISeS NCs did not exhibit better photoluminescence properties. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) pipelines are widely used in natural gas transmission systems in urban areas. With the acceleration of urbanization, the scale of PE natural gas pipelines has expanded rapidly. Thus, urban gas pipeline accidents caused by ground overload are inevitable. In this paper, the mechanical behavior of PE pipeline subjected to ground overload was investigated by the finite element method. PE pipe and soil were all established into a three-dimensional finite element model by using continuous solid elements. And parametric analysis was conducted to discuss the effects of pressure parameters, pipeline parameters and soil parameters on PE pipe's mechanical response. The numerical simulation results indicated that the main failure form of buried PE pipe subjected to ground overload is ovalization deformation. With the increase in ground load, the ovalization deformation of the pipeline increases gradually and the maximum stress point of the pipe is transferred from the top (bottom) of the pipe to the midsection of the pipe. The buried depth of pipe, the wall thickness of pipe, internal pressure and backfill type play a great role. Within a reasonable range, it will be safer if the pipe has greater wall thickness, buried depth and internal pressure. Meanwhile, the high soil's elasticity modulus and Poisson ratio backfill type are more conducive to the safety of buried PE pipelines. [ABSTRACT FROM AUTHOR]

Ti3+ self-doped TiO2/BCN heterojunction (Ti3+-TiO2/BCN) was constructed via a hydrothermal method with using NaBH4 as reducing agent. The BCN nanosheets function as a good support to block the agglomeration of Ti3+-TiO2 nanoparticles, which decreased the recombination of photogenerated charge carriers. The Ti3+-TiO2/BCN sample exhibited enhanced electronic conductivity and absorption in visible light region because of the introduction of Ti3+ and oxygen vacancies (Ov). The as-prepared Ti3+-TiO2/BCN sample showed enhanced photoelectrochemical (PEC) performance as confirmed by analyses of LSV, EIS, Bode plots and M-S. Under the visible light irradiation, the optimally Ti3+ self-doped TiO2/BCN heterojunction sample yield a photocurrent density of ∼ 0.69 mA/cm2 at 1.23 V versus RHE, which is over three times as high as BCN and TiO2/BCN at the same conditions. [ABSTRACT FROM AUTHOR]

One of the major areas of research in Horizontal Directional Drilling (HDD) technology is the accurate prediction of the pipeline pull-back load, which influences the project design schemes, selection of the drilling rig type and the mechanism of pull-back for reducing resistance. In this study, the possible contact state between the pipe and the hole is analysed based on the force exerted by the pipe in the circular sector of the hole, and the pull-back resistance of the pipe is calculated according to the bending beam theory. The full-scale model of the pipeline pull-back is established using numerical methods, the results of which are then compared to those obtained in the field test. In the numerical analysis, the resultant force of the mud buoyancy and pipeline gravity is substituted with an equivalent gravitational acceleration in the vertical direction. The results show that the pull-back force is not uniform when the pipe has just entered the hole. When the pull-back load is stabilised, the pull-back force of the pipeline is appropriately linear. After the pipe enters the hole, the variation curve of the pull-back force depends on the various values of the equivalent gravitation acceleration. [ABSTRACT FROM AUTHOR]

In this paper, the working principle and damage mechanism of the high-pressure manifold swivel joints were analyzed. The pressure distribution and velocity variation of the medium in the swivel joint are studied by CFD. The erosion areas and damage patterns of the swivel joints were investigated by practical research and theoretical analysis. Optimization design and improvement of the material, structural and processing technology were suggested. Those results can provide a reference for the design, manufacture and safety assessment of swivel joints. [ABSTRACT FROM AUTHOR]

Decorating a host semiconductor with quantum dots (QDs) is an important strategy for optimizing the separation efficiency and transfer of photogenerated charge carriers. In this work, we designed a heterojunction photoelectrocatalyst in which the (040) facet of BiVO4 was decorated with self-assembled Ag@AgCl QDs (“Ag@AgCl/040BiVO4”). In this photocatalyst, photogenerated charge carriers are efficiently separated using a Z-scheme approach. A facile oil-in-water self-assembly method was employed to generate the composite photocatalyst, which was then characterized via XRD, XPS, SEM, TEM, etc. The results of this characterization indicated that the Ag@AgCl QDs were approximately 5 nm in size and were well dispersed across the (040) crystal facet of BiVO4. PEC measurements indicated that the efficiency of electron-hole separation was enhanced when the BiVO4 was decorated with Ag@AgCl QDs on just one of its facets (040) rather than across all of its surface. An attempt was also made to elucidate the mechanism of interfacial charge transfer in the Ag@AgCl/040BiVO4 system. Decorating a specific crystal facet (040) of BiVO4 with Ag@AgCl QDs was found to facilitate the spatial separation of photogenerated charge carriers and to enhance the redox ability of the system. [ABSTRACT FROM AUTHOR]