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Science China Chemistry 2024年第7期67卷 2206-2214页

作者： menglin xie Ting Li Chao Wu Xiaoling Liu Jinling Ni Siqin Yao Yu Zhou Shibo Xi Jun Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Institute of Sustainability for Chemicals Energy and Environment(ISCE2)Agency for ScienceTechnology and Research(A*STAR)Singapore 627833Republic of Singapore College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

The selective oxidation of cyclohexane is a promising green route for the production of KA oil(cyclohexanol and cyclohexanone),but remains a huge challenge to design high-performing heterogeneous catalysts under mild ***,a pure silica ZSM-12(MTW topology)zeolite was applied as the support to immobilize highly dispersive tetrahedrally coordinated vanadium(V)species and the constructed catalyst 1%V/SZ-12 exhibited high efficiency in the fast and selective oxidation of cyclohexane into cyclohexanone with H_(2)O_(2).The reaction completed within 30 s,affording the selectivity of 99%towards cyclohexanone and the extremely high turnover frequency(TOF)of 5,891 h^(-1).1%V/SZ-12 was facilely reused with stable activity and feasibly extended to the oxidation of various cyclohexane *** one-dimensional 12-membered ring microchannels contributed to the formation and accessibility of tetrahedrally coordinated high valent V5+species as the robust active centers,which activated H_(2)O_(2) to generate V–O–O·,the active oxygen species for the electrophilic attack on cyclohexane to produce cyclohexanone as the sole product.

关键词： zeolite metal doping cyclohexane oxidation heterogeneous catalysis

妇科腹腔镜术后患者恶心呕吐症状认知与积极应对的质性研究

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临床与病理杂志 2024年第4期44卷 555-562页

作者：李春建邓雪莲蒋维连杨薇谢梦林桂林医学院第二附属医院妇科广西桂林541199 桂林医学院第二附属医院手术室广西桂林541199

目的:术后恶心呕吐是妇科腹腔镜手术常见并发症,阻碍了舒适护理和快速康复外科的发展进程。探讨妇科腹腔镜术后患者恶心呕吐症状认知及积极应对体验,为构建干预方案提供借鉴,加快舒适护理和加速康复外科的发展进程。方法:该研究为描述... 详细信息

目的:术后恶心呕吐是妇科腹腔镜手术常见并发症,阻碍了舒适护理和快速康复外科的发展进程。探讨妇科腹腔镜术后患者恶心呕吐症状认知及积极应对体验,为构建干预方案提供借鉴,加快舒适护理和加速康复外科的发展进程。方法:该研究为描述性现象学研究,采用目的抽样法,选取2023年2~4月在桂林医学院第二附属医院就诊的16例妇科腹腔镜术后恶心呕吐患者作为研究对象,进行半结构式深入访谈,采用Colaizzi 7步分析法归纳提炼主题。结果:归纳出4个主题(5个亚主题),包括恶心呕吐相关知识认知不足(缺乏系统的了解途径、缺乏影响因素相关知识、缺乏足够的重视)、恶心呕吐的症状体验(主要为迷走神经相关的症状,伴有循环系统的症状)、对患者情绪和社会交往造成程度不一的不良影响、多模式的应对方式(自我应对方式和专业支持)。结论:患者的症状认知和体验各不相同,自我应对策略依从性不佳,应规范健康宣教体系,建立有效的积极应对策略,以改善患者的心理状态,提高患者的就医体验。

关键词：腹腔镜术后恶心呕吐积极应对质性研究

Mass extinctions, their causes and consequences: an interview with Douglas *** and Shuzhong Shen

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng xie State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public *** spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

Turbulence Statistics of Thermo-Buoyancy Supercritical Fuel Flow in a Regenerative Cooling Channel

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Journal of Thermal Science 2024年第1期33卷 126-137页

作者： SUN Feng xie Gongnan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Active regenerative cooling with supercritical hydrocarbon fuel is considered as the most promising thermal protection *** existence of buoyancy force would lead to strongly anisotropic flow and thermal transport *** is closely related to the cooling performance of the *** elucidate the mechanisms of turbulent transport,the large eddy simulation(LES) was performed to assess turbulence statistics within different turbulence *** results indicated that the buoyancy and inertial force together dominated the change of turbulent ***,the spatial thermal buoyancy effect significantly suppressed the vertical velocity *** is due to the laminar motion caused by the buoyancy force,thereby weakening the thermal *** the statistics of velocity fluctuation,it was found that the buoyancy force and inertial force greatly weaken the vertical and streamwise velocity fluctuation,*** the statistics of thermal transport,the results pointed out that the near-wall heat transport characteristics need to be paid more *** thickness of the temperature mixing boundary layer led to the attenuation of vertical heat flux,which inhibited vertical temperature diffusion and predisposed to extreme conditions of heat transfer *** results can enhance the academic understanding of the heat transfer mechanism of supercritical fluids,and give guidance for further applications of thermal protection.

关键词： active regenerative cooling large eddy simulation(LES) buoyancy force turbulence statistics

Output feedback stabilization of stochastic high-order planar nonlinear systems with stochastic inverse dynamics and output-constraint

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Science China(Information Sciences) 2024年第3期67卷 182-196页

作者： Ruiming xie Shengyuan XU Nanjing University of Science and Technology School of Automation

In this paper, we solve the output feedback control problem of stochastic high-order planar nonlinear systems with output constraint and stochastic integral input-to-state stability(SiISS) inverse dynamics. By employing a key coordinate transformation, a stochastic nonlinear system with output constraint and SiISS inverse dynamics is converted into an unconstrained system. By skillfully constructing an observer and adopting SiISS small-gain conditions, we develop a new output feedback control design and analysis method, and prove that all the closed-system signals are bounded almost surely, the output constraint is not violated almost surely, and the equilibrium point of the closed-loop system is stochastically asymptotically stable.

关键词： stochastic high-order planar nonlinear system outputconstraint stochastic inverse dynamics output feedbackstabilization stochastic integral input-to-state stability(SiISS)

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Fixed-time stabilization of output-constrained stochastic high-order nonlinear systems

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Science China(Information Sciences) 2024年第4期67卷 5-20页

作者： Ruiming xie Shengyuan XU Nanjing University of Science and Technology School of Automation

In this study, the fixed-time stabilization problem of stochastic high-order nonlinear systems with output constraint and high-order and low-order nonlinearities is addressed. A new coordinate transformation is employed to directly convert output-constrained stochastic systems into an equivalent unconstrained *** fully extracting the characteristics of system nonlinearities and using the stochastic fixed-time stability theorem, a new design and analysis method is constructed to guarantee that the trivial solution of the closed-loop system is stochastically fixed-time stable while fulfilling the output constraint.

关键词： stochastic high-order nonlinear system outputconstraint high-order and low-order nonlinearity fixed-timestabilization finite-time stabilization

Review of the research on the development and utilization of clay-type lithium resources

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Particuology 2024年第4期87卷 46-53页

作者： Ruiqi xie Zhihui Zhao Xiong Tong Xian xie Qiang Song Peiqiang Fan Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Yunnan Engineering Research Center for Metal Tailings Resource Utilization Kunming650093China

Since the demands for lithium have been in explosive growth recently and several great clay lithium resources were founded in China,the development and utilization of clay-type lithium resources become a hot *** order to provide a guidance for the concentration and extracting lithium of clay-type lithium resources,this review systematically summarized the main types and characteristics of clay-type lithium resources and the research status of lithium extraction from clay lithium ***,the flotation research status of the main mineral of clay lithium ore was also ***,we discussed the difficulties in the development and utilization of clay-type lithium ore and put forward the subsequent research *** paper can provide a guidance for the con-centration and extracting lithium of clay-type lithium resources in the future.

关键词： Clay lithium Clay mineral flotation Lithium extraction Leaching

Conductive and stable polyphenylene/CNT composite membrane for electrically enhanced membrane fouling mitigation

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 35-47页

作者： Huijuan xie Haiguang Zhang Xu Wang Gaoliang Wei Shuo Chen xie Quan Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

Nanocarbon-based conductive membranes, especially carbon nanotube (CNT)-based membranes, have tremendous potential for wastewater treatment and water purification because of their excellent water permeability and selectivity, as well as their electrochemically enhanced performance (e.g., improved antifouling ability). However, it remains challenging to prepare CNT membranes with high structural stability and high electrical conductivity. In this study, a highly electroconductive and structurally stable polyphenylene/CNT (PP/CNT) composite membrane was prepared by electropolymerizing biphenyl on a CNT hollow fiber membrane. The PP/CNT membrane showed 3.4 and 5.0 times higher electrical conductivity than pure CNT and poly(vinyl alcohol)/CNT (PVA/CNT) membranes, respectively. The structural stability of the membrane was superior to that of the pure CNT membrane and comparable to that of the PVA/CNT membrane. The membrane fouling was significantly alleviated under an electrical assistance of −2.0 V, with a flux loss of only 11.7% after 5 h filtration of humic acid, which is significantly lower than those of PP/CNT membranes without electro-assistance (56.8%) and commercial polyvinylidene fluoride (PVDF) membranes (64.1%). Additionally, the rejection of negatively charged pollutants (humic acid and sodium alginate) was improved by the enhanced electrostatic repulsion. After four consecutive filtration-cleaning cycle tests, the flux recovery rate after backwashing reached 97.2%, which was much higher than those of electricity-free PP/CNT membranes (67.0%) and commercial PVDF membranes (61.1%). This study offers insights into the preparation of stable conductive membranes for membrane fouling control in potential water treatment applications.

关键词： Polyphenylene CNTs Membrane Electro-assistance Membrane fouling mitigation

Transfer learning framework for multi-scale crack type classification with sparse microseismic networks

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International Journal of Mining Science and Technology 2024年第2期34卷 167-178页

作者： Arnold Yuxuan xie Bing QLi Department of Civil and Environmental Engineering Western UniversityLondon N6A 3K7Canada

Rock fracture mechanisms can be inferred from moment tensors(MT)inverted from microseismic ***,MT can only be inverted for events whose waveforms are acquired across a network of *** is limiting for underground mines where the microseismic stations often lack azimuthal ***,there is a need for a method to invert fracture mechanisms using waveforms acquired by a sparse microseismic ***,we present a novel,multi-scale framework to classify whether a rock crack contracts or dilates based on a single *** framework consists of a deep learning model that is initially trained on 2400000+manually labelled field-scale seismic and microseismic waveforms acquired across 692 *** learning is then applied to fine-tune the model on 300000+MT-labelled labscale acoustic emission waveforms from 39 individual experiments instrumented with different sensor layouts,loading,and rock types in *** optimal model achieves over 86%F-score on unseen waveforms at both the lab-and *** model outperforms existing empirical methods in classification of rock fracture mechanisms monitored by a sparse microseismic *** facilitates rapid assessment of,and early warning against,various rock engineering hazard such as induced earthquakes and rock bursts.

关键词： Multi-scale Fracture processes Microseismic Acoustic emission Source mechanism Deep learning

Influence characteristics of water penetration on fibre-reinforced polymer/rigid polyurethane foam interface of the composite cross-arm considering natural ageing

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High Voltage 2024年第1期9卷 81-93页

作者： Jun xie Zhe Zhou Ziqian Liu Haonan Tian Sigang Zhang Qing xie Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina State Grid Gansu Electric Power Company LanzhouChina

Fibre-reinforced polymer(FRP)/rigid polyurethane foam(RPUF)interface is susceptible to moisture intrusion in addition to natural ageing during *** study investigated the influence of moisture intrusion on the FRP/RPUF interface under natural ageing using experiments and molecular dynamics(MD)*** absorption,shear strength,and leakage current tests were used to clarify the changes in the interface *** degradation mechanism of moisture intrusion at the interface under natural ageing was revealed by MD simulation and *** results show that the natural ageing of interfacial materials will slightly reduce the quality of the interface but will reduce the water resistance of the material and promote the process of water intrusion into the *** addition,water mainly invades the interface through *** water penetration,the interfacial bonding strength and insulation performance significantly *** and hydrolysis of interfacial materials are the main reasons for decreased interfacial *** can cause irreversible damage to the interface,increasing interface defects and water *** vicious cycle of material hydrolysis is the ultimate cause of interfacial *** polar molecules produced by this process and the water absorbed by the interface caused the degradation of the interface insulation performance.

关键词： interface polyurethane interfacial