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First-Principles Study on Hexagonal WO_3 for HCHO Gas Sensing Application

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 772-780页

作者： Bo-Lin Tang Guo-Hua Jiang wen-xing chen Jun-Min Wan Department of Materials Engineering Zhejiang Sci-Tech University Key Laboratory of Advanced Textile Materials and Manufacturing Technology (ATMT) Ministry of Education National Engineering Laboratory for Textile Fiber Materials and Processing Technology (Zhejiang)

The adsorption energy, electronic structure, density of states, and electron population for adsorption of HCHO on the hexagonal WO3 （h-WO3）（001） surfaces were investigated by density functional theory calculations. The adsorption energy of HCHO molecule on W and O sites of WO-terminated h-WO3 （001） surface was -0.309 and -0.432 eV compared with the value at -1.936 eV for HCHO molecule on O-terminated h-WO3 （001） surface. According to the calculated results, the adsorption of HCHO on h-WO3 （001） surface was spontaneous with physical adsorption on WO- terminated h-WO3 （001） surface and chemisorption on O-terminated h-WO3 （001） surface. The charge transfer from adsorbed HCHO molecule to WO3 （001） surface was confirmed by the Mulliken population analysis, which suggested the potential application of h-WO3 for HCHO gas detection.

关键词： Semiconductors Surfaces Crystal structure Electronic structure

Preparation of Mesoporous Bi_4(GeO_4)_3 Microspheres from Na_4Ge_9O_(20) Template Microspheres for Photodegradation of Reactive Brilliant Red X-3B

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1156-1161页

作者： Hua chen Guo-Hua Jiang Yong-Kun Liu Lei Li Qin Huang wen-xing chen Department of Materials Engineering Zhejiang Sci-Tech University National Engineering Laboratory for Textile Fiber Materials and Processing Technology (Zhejiang) Key Laboratory of Advanced Textile Materials and Manufacturing Technology (ATMT) Ministry of Education

Mesoporous materials have attracted increasing attention due to their wide application. In this paper, the Na4Ge9020 microspheres were firstly prepared by solvothermal method. Then, the as-prepared Na4Ge9020 microspheres were dispersed into Bi（NO3）3 solution, and the Bi4（GeO4）3 microspheres with mesoporous structure were formed due to the solid-state reaction between bismuth nitrate and Na4Ge9020. The morphology, structure and optical properties were characterized by SEM, EDS, XRD, FITR, BET and UV-Vis diffuse reflectance analysis. The as-prepared products exhibited excellent photocatalytic performance for degradation of reactive brilliant red X-3B under the UV light irradi- ation. A possible photocatalytic mechanism was discussed as well.

关键词： Mesoporous Microspheres Photocatalysis

Effects of N and/or S Doping on Structure and Photocatalytic Properties of BiOBr Crystals

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 460-466页

作者： Guo-Hua Jiang Xia Li Zhen Wei Teng-Teng Jiang Xiang-Xiang Du wen-xing chen Key Laboratory of Advanced Textile Materials and Manufacturing Technology (ATMT) Ministry of EducationZhejiang Sci-Tech University Department of Materials Engineering College of Materials and TextileZhejiang Sci-Tech University

The BiOBr crystals doped with N and/or S have been prepared by a facile and rapid solvothermal method using urea and/or thiourea as doped resource. The morphologies and structures of the as-prepared samples were characterized by SEM, TEM, XRD, XPS and PL spectrum. Their electronic structures have been investigated and discussed using first principles based on the density functional theory. The photocatalytic properties of the products can be adjusted by the content and species of dopants.

关键词： Hydrothermal method Photocatalysis Microstructure and properties

Atomically Dispersed Dual‑Metal Sites Showing Unique Reactivity and Dynamism for Electrocatalysis

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Nano-Micro Letters 2023年第8期15卷 192-204页

作者： Jun‑Xi Wu wen‑xing chen Chun‑Ting He Kai Zheng Lin‑Ling Zhuo Zhen‑Hua Zhao Jie‑Peng Zhang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-Sen UniversityGuangzhou 510275People’s Republic of China Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022People’s Republic of China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China

The real structure and in situ evolution of catalysts under working conditions are of paramount importance,especially for bifunctional ***,we report asymmetric structural evolution and dynamic hydrogen-bonding promotion mechanism of an atomically dispersed *** of Co/Ni-doped MAF-4/ZIF-8 yielded nitrogen-doped porous carbons functionalized by atomically dispersed Co–Ni dual-metal sites with an unprecedented N8V4 structure,which can serve as an efficient bifunctional electrocatalyst for overall water *** importantly,the electrocatalyst showed remarkable activation behavior due to the in situ oxidation of the carbon substrate to form C–OH *** functional theory calculations suggested that the flexible C–OH groups can form reversible hydrogen bonds with the oxygen evolution reaction intermediates,giving a bridge between elementary reactions to break the conventional scaling relationship.

关键词： Metal-organic frameworks Atomically dispersed catalyst Hydrogen bond Overall water splitting

Wave effect of gravitational waves intersected with a microlens field Ⅱ:An adaptive hierarchical tree algorithm and population study

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 241-254页

作者： Xikai Shan Guoliang Li Xuechun chen wen Zhao Bin Hu Shude Mao Department of Astronomy Tsinghua University Purple Mountain Observatory Chinese Academy of Sciences Institute for Frontier in Astronomy and Astrophysics Beijing Normal University School of Physics and Astronomy Beijing Normal University School of Astronomy and Space Science University of Science and Technology of China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of Astronomy University of Science and Technology of ChinaChinese Academy of Sciences

The gravitational lensing wave effect generated by a microlensing field embedded in a lens galaxy is an inevitable phenomenon in strong lensed gravitational waves （SLGWs）.This effect presents both challenges and opportunities for the detection and application of ***,investigating this wave effect requires computing a complete diffraction integral over each microlens in the *** is extremely time-consuming due to the large number of microlenses （10～3-10～6）.Therefore,simply adding all the microlenses is ***,the complexity of the time delay surface makes the lens plane resolution a crucial factor in controlling numerical *** this paper,we propose a trapezoid approximation-based adaptive hierarchical tree algorithm to meet the challenges of calculation speed and *** find that this algorithm accelerates the calculation by four orders of magnitude compared to the simple adding method and is one order of magnitude faster than the fixed hierarchical tree algorithm proposed for electromagnetic *** importantly,our algorithm ensures controllable numerical errors,increasing confidence in the *** with our previous work （***.66,239511,2023）,this paper addresses all numerical issues,including integral convergence,precision,and computational time1).Finally,we conducted a population study on the microlensing wave effect of SLGWs using this algorithm and found that the microlensing wave effect cannot be ignored,especially for Type II SLGWs （from saddle position of the time delay surface） due to their intrinsic geometric structures and their typical intersection with a denser microlensing ***,more than 33%（11%） of SLGWs have a mismatch larger than 1%（3%） compared to the unlensed ***,we found that the mismatch between signal pairs in a doubly imaged GW is generally larger than 10-3,and 61%（25%） of signal pairs have a mismatch larger than 1%（3%）.Therefo

关键词： gravitational lensing diffractional integral algorithm gravitational wave

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聚丙烯腈纳米纤维的高效制备及结晶取向性能

高分子学报 2018年第6期28卷 755-764页

作者：王振安李楠吕汪洋陈文兴浙江理工大学纺织纤维材料与加工技术国家地方联合工程实验室杭州310018

分别采用传统静电纺丝装置和自行搭建的离心-静电纺丝装置制备出聚丙烯腈(PAN)纳米初生纤维,并在热空气浴中和一定外力作用下进行牵伸,牵伸后使其伸长至原长的1倍到3倍.通过广角X射线衍射(WAXD)、扫描电子显微镜(SEM)等方法对2种纺丝方... 详细信息

分别采用传统静电纺丝装置和自行搭建的离心-静电纺丝装置制备出聚丙烯腈(PAN)纳米初生纤维,并在热空气浴中和一定外力作用下进行牵伸,牵伸后使其伸长至原长的1倍到3倍.通过广角X射线衍射(WAXD)、扫描电子显微镜(SEM)等方法对2种纺丝方法制备的PAN纳米初生纤维及经过热空气浴牵伸后的PAN纳米纤维的晶态结构、取向及形貌等进行了表征.研究表明:(1)离心-静电纺丝效率远高于静电纺丝,可达静电纺丝的120倍(离心-静电纺丝纺丝液流速为2 m L/min,静电纺丝纺丝液流速1 m L/h);(2)无论是离心纺丝还是静电纺丝制得的纳米初生纤维结晶度均很低(离心纺丝为25%,静电纺丝为10.1%),但离心纺丝制得的纳米初生纤维有一定的取向(60.5%),而静电纺丝基本没有;(3)经过热空气浴牵伸后,2种纺丝方式制得的纳米纤维结晶度均有所提高(分别为45.8%和36.2%),取向度也有所提高(分别为72.5%和59.8%),随着牵伸温度的提高和牵伸应力的增大,纤维的平均直径不断减小(离心纺丝由675 nm降至510 nm,静电纺丝由460 nm降至355 nm).纳米纤维在制备过程晶态结构及取向的效果有限,但通过热空气浴牵伸可以使晶态结构及取向得到进一步完善.

关键词：离心纺丝静电纺丝聚丙烯腈晶态结构和取向

Graphene Aerogel Composites with Self‑Organized Nanowires‑Packed Honeycomb Structure for Highly Efficient Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 533-547页

作者： Xiao You Huiying Ouyang Ruixiang Deng Qiuqi Zhang Zhenzhong xing Xiaowu chen Qingliang Shan Jinshan Yang Shaoming Dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory of Inorganic Coating Materials CAS Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210People’s Republic of China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China University of Chinese Academy of Sciences Beijing 100039People’s Republic of China

With vigorous developments in nanotechnology,the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave ***,a hierarchical porous structure and composite heterogeneous interface are constructed successfully to optimize the electromagnetic loss *** macro–micro-synergistic graphene aerogel formed by the ice template‑assisted 3D printing strategy is cut by silicon carbide nanowires(SiC_(nws))grown in situ,while boron nitride(BN)interfacial structure is introduced on graphene *** unique composite structure forces multiple scattering of incident EMWs,ensuring the combined effects of interfacial polarization,conduction networks,and magnetic-dielectric ***,the as-prepared composites present a minimum reflection loss value of−37.8 dB and a wide effective absorption bandwidth(EAB)of 9.2 GHz(from 8.8 to 18.0 GHz)at 2.5 ***,relying on the intrinsic high-temperature resistance of SiC_(nws) and BN,the EAB also remains above 5.0 GHz after annealing in air environment at 600℃ for 10 h.

关键词： Hierarchical porous structure Interface High-temperature resistance Graphene aerogel composites Electromagnetic wave absorption

云南绿春县天然次生林和4种人工林树冠层蚂蚁群落多样性

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林业科学研究 2017年第5期30卷 823-830页

作者：赵婧文卢志兴陈又清中国林业科学研究院资源昆虫研究所云南昆明650224

[目的]探讨天然次生林和人工林及人工林树种选择对树冠层蚂蚁群落多样性的影响。[方法]运用树栖蚂蚁陷阱法调查云南省绿春县天然次生林和4种人工林的树冠层蚂蚁群落、植物多样性及植物垂直密度变化。[结果](1)共采集蚂蚁标本17 998头,... 详细信息

[目的]探讨天然次生林和人工林及人工林树种选择对树冠层蚂蚁群落多样性的影响。[方法]运用树栖蚂蚁陷阱法调查云南省绿春县天然次生林和4种人工林的树冠层蚂蚁群落、植物多样性及植物垂直密度变化。[结果](1)共采集蚂蚁标本17 998头,隶属于6亚科29属68种。(2)树冠层蚂蚁多度:紫胶林-玉米混农林>紫胶林>桉树林>橡胶林>天然次生林。(3)树冠层蚂蚁丰富度:紫胶林-玉米混农林>紫胶林>天然次生林>橡胶林>桉树林。(4)树冠层蚂蚁ACE估计值:紫胶林-玉米混农林>紫胶林>天然次生林>桉树林>橡胶林。(5)树冠层蚂蚁多度和丰富度与枯落物盖度、>300 cm处垂直密度和乔木郁闭度呈显著或极显著负相关,而与植物盖度显著正相关;ACE估计值与枯落物盖度、草本植物盖度和乔木郁闭度显著负相关,与175 199.9 cm区段内垂直密度显著正相关。[结论]人工林对蚂蚁多样性保护有一定积极作用,尤其选择乡土树种保护效果更显著,对人工林进行合理的管理有利于保护生物多样性。

关键词：天然次生林人工林树种选择树冠层蚂蚁群落多样性

PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong Liu Xiaolin Li Xiaowei Zhou Wei chen Aidong wen Minna Liu Yi Ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics