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Chinese Journal of Structural Chemistry 2022年第1期41卷 34-39页

作者： Ya Liu Fangbo yu Feng wang Shengjie Bai Guiwei He State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

Producing chemical fuels from sunlight enables a sustainable way for energy *** various solar fuel generation approaches,photocatalytic CO_(2) reduction has the advantages of simple structure,mild reaction condition,directly reducing carbon emissions,***,most of the current photocatalytic systems can only absorb the UV-visible spectrum of solar ***,finding a way to utilize infrared light in the photocatalytic system has attracted more and more ***,a Z-scheme In_(2)S_(3)-TiO_(2) was constructed for CO_(2) reduction under concentrated natural *** infrared light was used to create a high-temperature environment for photocatalytic *** evolution rates of H2,CO,and C2H5OH reached 262.2,73.9,and 27.56μmol・h^(-1)・g^(-1),respectively,with an overall solar to fuels efficiency of 0.002%.This work provides a composite photocatalyst towards the utilization of full solar light spectrum,and could promote the research on photocatalytic CO_(2) reduction.

关键词： solar energy CO_(2) In_(2)S_(3) TiO_(2)

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Melting Temperature of Individual Electrospun Poly(vinylidene fluoride) Fibers Studied by AFM-based Local Thermal Analysis

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Chinese Journal of Polymer Science 2021年第2期39卷 219-227,I0007页

作者： Ze-Qian wang Zhen-Xing Zhong yu-Ying Ma Xiao-Feng Lu Ce wang Zhao-Hui Su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Alan G.MacDiarmid Institute Jilin UniversityChangchun 130012China

Thermal properties such as melting temperature can well reflect the microstructure of the polymer material, and have practical implications in the application of nanofibers. In this work, we investigated the melting temperature of individual electrospun poly(vinylidene fluoride)(PVDF) nanofibers with diameters ranging from smaller than 200 nm to greater than 2 μm by the local thermal analysis technique. The PVDF fibers obtained under four different conditions were found to crystallize into α and β phases, and the fiber mats showed typical values in the crystallinity and Tm with no significant difference among the four. However, analyses at single fiber level revealed broad distribution in diameter and Tm for the fibers produced under identical electrospinning condition. The Tm of individual nanofibers was found to remain constant at large diameters and increase quickly when reducing the fiber diameter toward the nanoscale, and Tm values of 220-230 ℃ were observed for the thinnest nanofibers, much higher than the typical values reported for bulk PVDF. The Tm and molecular orientation at different positions along a beaded fiber were analyzed, showing a similar distribution pattern with a minimum at the bead center and higher values when moving toward both directions. The results indicate that molecular orientation is the driving mechanism for the observed correlation between the Tm and the diameter of the nanofibers.

关键词： Electrospun fibers PVDF Local thermal analysis Melting temperature

Effects of acupuncture on hypothalamic–pituitary–adrenal axis:Current status and future perspectives

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Journal of Integrative Medicine 2024年第4期22卷 445-458页

作者： Jia-yuan Zheng Jing Zhu yu wang Zhan-zhuang Tian Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceInstitute of Acupuncture ResearchAcademy of Integrative MedicineShanghai Key Laboratory for Acupuncture Mechanism and Acupoint FunctionShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Human Anatomy School of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

The hypothalamic–pituitary–adrenal(HPA) axis is a critical component of the neuroendocrine system,playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus,hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA *** review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture.

关键词： Acupuncture Electroacupuncture Hypothalamic-pituitary-adrenal axis Mechanism Neurotransmitter microRNA

Acoustic characteristics of cold-seep methane bubble behavior in the water column and its potential environmental impact

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Acta Oceanologica Sinica 2020年第5期39卷 133-144页

作者： Jiangong Wei Tingting Wu Xiguang Deng Zongze yu Lifeng wang Gas Hydrate Engineering and Technology Center Guangzhou Marine Geological SurveyGuangzhou 510075China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyGuangzhou 510075China

The amount of methane leaked from deep sea cold seeps is enormous and potentially affects the global warming,ocean acidification and global carbon *** is of great significance to study the methane bubble movement and dissolution process in the water column and its output to the *** bubbles produce strong acoustic impedance in water bodies,and bubble strings released from deep sea cold seeps are called"gas flares"which expressed as flame-like strong backscatter in the water *** characterized the morphology and movement of methane bubbles released into the water using multibeam water column data at two cold *** result shows that methane at site I reached 920 m water depth without passing through the top of the gas hydrate stability zone(GHSZ,850 m),while methane bubbles at site II passed through the top of the GHSZ(597 m)and entered the non-GHSZ(above 550 m).By applying two methods on the multibeam data,the bubble rising velocity in the water column at sites I and II were estimated to be 9.6 cm/s and 24 cm/s,*** velocity is positively associated with water depth which is inferred to be resulted from decrease of bubble size during methane ascending in the *** with numerical simulation,we concluded that formation of gas hydrate shells plays an important role in helping methane bubbles entering the upper water bodies,while other factors,including water depth,bubble velocity,initial kinetic energy and bubble size,also influence the bubble residence time in the water and the possibility of methane entering the *** estimate that methane gas flux at these two sites is 0.4×10~6–87.6×10~6 mol/a which is extremely small compared to the total amount of methane in the ocean body,however,methane leakage might exert significant impact on the ocean acidification considering the widespread distributed cold *** addition,although methane entering the atmosphere is not observed,further research is still needed to

关键词： gas bubble methane cold seep Nigerian Continental Margin Greenhouse effect Makran accretion wedge

Application of networked discrete event system theory on intelligent transportation systems

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Control Theory and Technology 2021年第2期19卷 236-248页

作者： Jiayuan Liang Chaohui Gong yunfeng Hou Miao yu Weilin wang School of Optical-Electrical and Computer Engineering University for Shanghai Science and TechnologyShanghai200093China Zhejiang Research Center on Smart Rail Transportation PowerChina Huadong Engineering Corporation LimitedHangzhouZhejiang311225China

The responses of vehicles to the changes in traffic situations inevitably have delays in observing an event and implementing a control command,which often causes fatal *** far,the methods for handling delays are empirical and cannot be mathematically *** eliminate the accidents caused by such delays,in this paper,we develop mathematically provable methods to handle these ***,we use networked discrete event systems to model the process of driving vehicles and present a supervisory controller for handling delay *** method developed in this paper could serve as a new start for modeling and controlling the responsive behaviors of self-driving vehicles in the future.

关键词： Discrete event systems Automata Supervisory control Automated driving systems

Mechanical anisotropy associated with beddings in shale under Brazilian test conditions:Insights from acoustic emission statistics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第11期16卷 4462-4479页

作者： Yongfa Zhang Yinlin Ji yu Zhao Qinglin Deng Chaolin wang College of Civil Engineering Guizhou UniversityGuiyang550025China Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesPotsdam14473Germany State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resource and Safety EngineeringChongqing UniversityChongqing400044China

A comprehensive understanding of shale’s bedding anisotropy is crucial for shale-related engineering activities,such as hydraulic fracturing,drilling and underground *** this study,seven Brazilian tests were conducted on shale samples at different bedding orientations with respect to the loading direction(0°,45°and 90°)and the disc end face(0°,45°and 90°).An acoustic emission(AE)system was employed to capture the evolution of damage and the temporal-spatial distribution of microcracks under splitting-tensile *** results show that the Brazilian tensile strength decreases with increasing bedding inclination with respect to the disc end face,while it increases with the angle between bedding and loading *** the bedding inclination with respect to the end face facilitates the reduction in b value and enhances the shale’s resistance to microcrack growth during the loading *** between the bedding orientation and the end face suppresses the growth of mixed tensile-shear microcracks,while reducing the bedding angle relative to the loading direction is beneficial for creating mixed tensile-shear and tensile *** observed microscopic failure characteristics are attributed to the competing effects of bedding activation and breakage of shale matrix at different bedding *** temporal-spatial distribution of microcracks,characterized by AE statistics including the correlation dimension and spatial correlation length,illustrates that the fractal evolution of microcracks is independent of bedding anisotropy,whereas the spatial distribution shows a stronger *** evolution features of correlation dimension and spatial correlation length could be potentially used as precursors for shale splitting *** findings may be useful for predicting rock mass instability and analyzing the causes of catastrophic rupture.

关键词： Bedding anisotropy Acoustic emission(AE) Shale Brazilian test Rock failure mechanism Splitting-tensile cracks

Formation of ZnSe magic-size clusters displaying optical absorption doublets from prenucleation clusters

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Nano Research 2024年第7期17卷 6741-6748页

作者： Dingyu Zhao Shasha wang Jiawei Xue Chunchun Zhang Shanling wang Xiaoqin Chen Chaoran Luan Kui yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China Analytical&Testing Center Sichuan UniversityChengdu 610065China College of Biomedical Engineering Sichuan UniversityChengdu 610065China

The formation pathway of colloidal semiconductor ZnSe magic-size clusters(MSCs)in a reaction that display an optical absorption doublet remains poorly *** reaction of Zn(OAc)_(2)/OLA(made from zinc acetate and oleylamine)and tri-noctylphosphine selenide(SeTOP)in OLA in the presence of diphenylphosphine(HPPh_(2))is studied,in which dMSC-345 displays a doublet peaking at 328/345 *** suggest that the development is from the clusters that form in the initial prenucleation stage of the *** clusters are the precursor compound(PC-299)of MSC-299(displaying an absorption singlet peaking at 299 nm).PC-299 transforms to PC-345 at a later *** presence of alcohol(such as methanol or ethylene glycol)promotes another pathway,which is the PC-299 to PC-320 ***-320 transforms to dMSC-320(with a doublet at 305/320 nm),followed by dMSC-345 via *** present study provides additional evidence that clusters(PC-299)form and transform(such as to dMSC-345 via PC-345)in the prenucleation stage of ZnSe quantum dots(QDs).

关键词： magic-size cluster(MSC) prenucleation cluster precursor compound(PC) quantum dot(QD) zinc selenide(ZnSe)

What Role Does the Political Environment Play in Economic Development？ --A Case Study of Fujian Province

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2012年第4期7卷 544-559页

作者： Jingwen yu Chunchao wang School of Economics Fudan University Shanghai 200433 China Department of Economics Jinan University Guangzhou 510632 China

Uncertainty induced by the political environment affects investment risk, and thus affects investment decisions, which have a close relationship with economic development. This paper investigates the economic cost of political instability using the case study of the tense relationship across-Strait in China. We use a synthetic control method to better model the counterfactual analysis of this case study. The intense situation of the relations across-Strait has great influence on the economic development of Fujian province. Fujian province is the closest province in proximity to Taiwan and also possesses the greatest preferential policies for Taiwan Residents direct investment. The empirical results of this study reveal that during 2001-2008 Fujian province＇s average annual loss in GDP per capita was 682.54 yuan. In other words, GDP per capita in Fujian has declined about 12.1 percent annually during this period compared with GDP per capita as calculated by the synthetic control method.

关键词： political environment economic development synthetic controlmethod cross-straits relations

Mutual impact of true triaxial stress, borehole orientation and bedding inclination on laboratory hydraulic fracturing of Lushan shale

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3131-3147页

作者： Yongfa Zhang Anfa Long yu Zhao Arno Zang Chaolin wang College of Civil Engineering Guizhou UniversityGuiyang550025China Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesPotsdam14473Germany

Unconventional resources like shale gas has been the focus of intense research and development for two decades. Apart from intrinsic geologic factors that control the gas shale productivity (e.g. organic matter content, bedding planes, natural fractures, porosity and stress regime among others), external factors like wellbore orientation and stimulation design play a role. In this study, we present a series of true triaxial hydraulic fracturing experiments conducted on Lushan shale to investigate the interplay of internal factors (bedding, natural fractures and in situ stress) and external factors (wellbore orientation) on the growth process of fracture networks in cubic specimens of 200 mm in length. We observe relatively low breakdown pressure and fracture propagation pressure as the wellbore orientation and/or the maximum in situ stress is subparallel to the shale bedding plane. The wellbore orientation has a more prominent effect on the breakdown pressure, but its effect is tapered with increasing angle of bedding inclination. The shale breakdown is followed by an abrupt response in sample displacement, which reflects the stimulated fracture volume. Based on fluid tracer analysis, the morphology of hydraulic fractures (HF) is divided into four categories. Among the categories, activation of bedding planes (bedding failure, BF) and natural fractures (NF) significantly increase bifurcation and fractured areas. Under the same stress regime, a horizontal wellbore is more favorable to enhance the complexity of hydraulic fracture networks. This is attributed to the relatively large surface area in contact with the bedding plane for the horizontal borehole compared to the case with a vertical wellbore. These findings provide important references for hydraulic fracturing design in shale reservoirs.

关键词： True triaxial hydraulic fracturing experiment In situ stress state Bedding planes Natural fractures Wellbore orientation Shale reservoirs