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Chinese Journal of Polymer Science 2024年第10期42卷 1566-1577页

作者： Shu-Juan Wang Lu Wang Hong-Zhe Su Zhi-Cheng Wu Qiao-Gen Zhang Wei Fan xin-li jing School of Chemistry Joint Innovation Center of Thermal Protection Materials Xi'an Jiaotong University School of Electrical Engineering Xi'an Jiaotong University School of Textile Science and Engineering Xi'an Polytechnic University

Polydimethylsiloxane (PDMS) is an electron-withdrawing material that is widely used in triboelectric nanogenerators (TENGs). However, PDMS has poor mechanical properties after curing and is easily damaged when subjected to long-term workloads. Thus, the long-term stable operation of TENGs under mechanical deformation cannot be guaranteed. In this work, multiple hydrogen bonds and aromatic disulfide bonds were introduced into PDMS elastomers. These elastomers exhibited high toughness (a tensile strength of 1.91 MPa and an elongation at break of 340%), good recyclability, and room-temperature self-healing properties (healing efficiency of 96.4%in 24 h). Recyclable sandwich-like triboelectric nanogenerators with excellent electrical output performance (13.5 V) and room-temperature self-healing performance (24 h, 98% recovery of self-generating performance) were prepared by utilizing the hydrogen bonding between the PDMS elastomer and MXene. The work reported herein offers theoretical guidance and a compelling strategy for developing high-performance TENG negative friction layers.

关键词： Aromatic disulfide bonds Hydrogen bonds Polydimethylsiloxane Room temperature self-healing Triboelectric nanogenerator

季节性生态旅游地的旅游化过程与机制及其启示——基于新疆赛里木湖案例

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自然资源学报 2024年第7期39卷 1626-1642页

作者：梁增贤李新静中山大学旅游学院珠海519082 新疆历史文化旅游可持续发展重点实验室乌鲁木齐830046

如何平衡保护与开发、淡季与旺季问题是促进生态旅游地高质量发展的关键,而旅游化是生态地区常用的平衡途径。然而,现有旅游化研究缺乏有效的分析工具和解释机制,难以厘清旅游地历时态的阶段性特征、因果机制及其时空影响。拓展旅游化... 详细信息

如何平衡保护与开发、淡季与旺季问题是促进生态旅游地高质量发展的关键,而旅游化是生态地区常用的平衡途径。然而,现有旅游化研究缺乏有效的分析工具和解释机制,难以厘清旅游地历时态的阶段性特征、因果机制及其时空影响。拓展旅游化理论的应用情境,构建包含时空维度的旅游化模型,并开展案例研究,采用观察法、访谈法和收集二手数据等方式获得多源数据,解释与厘清新疆赛里木湖景区由生态牧场到成熟生态旅游地20多年的旅游化过程及其内在机制。研究表明:赛里木湖的旅游化经历政府主导的内部空间旅游化、政府主导的外部空间旅游化、企业主导的深度时空旅游化、政企主导的淡季时间旅游化四个阶段,总体上呈现先内部旅游化、再外部旅游化及先旺季和白天的旅游化、再夜间和淡季旅游化等特征。赛里木湖旅游化的各阶段互有交叉,解决的关键问题和旅游化的驱动力均不同。其中,内部旅游化是构建吸引力的重点,外部旅游化是发挥吸引力的关键,二者应相互协调。本文提出的旅游化模型为理解旅游化的演进规律和各阶段的因果关系及其影响提供了分析工具,为生态旅游地平衡保护与开发、破解淡旺季供需矛盾、促进高质量发展提供路径指引和案例借鉴。

关键词：生态旅游旅游化季节性旅游目的地赛里木湖

Improved BP Neural Network for Transformer Fault Diagnosis

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Journal of China University of Mining and Technology 2007年第1期17卷 138-142页

作者： SUN Yan-jing ZHANG Shen MIAO Chang-xin li jing-meng School of Information and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The back propagation (BP)-based artificial neural nets (ANN) can identify complicated relationships among dissolved gas contents in transformer oil and corresponding fault types, using the highly nonlinear mapping nature of the neural nets. An efficient BP-ALM (BP with Adaptive Learning Rate and Momentum coefficient) algorithm is proposed to reduce the training time and avoid being trapped into local minima, where the learning rate and the momentum coefficient are altered at iterations. We developed a system of transformer fault diagnosis based on Dissolved Gases Analysis (DGA) with a BP-ALM algorithm. Training patterns were selected from the results of a Refined Three-Ratio method (RTR). Test results show that the system has a better ability of quick learning and global convergence than other methods and a superior performance in fault diagnosis compared to convectional BP-based neural networks and RTR.

关键词： transformer fault diagnosis back-propagation artificial neural network momentum coefficient

Synthesis of Nitrogen-Doped Graphene via Thermal Annealing Graphene with Urea

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Chinese Journal of Chemical Physics 2012年第3期25卷 325-329,374页

作者： xin-jing li xin-xin Yu Jin-yang liu Xiao-dong Fan Kun Zhang Hong-bing Cai Nan Pan Xiao-ping Wang Department of Physics University of Science and Technology of China Hefei 230026 China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Tech-nology of China Hefei 230025 China

Chemical doping is an effective method to intrinsically modify the chemical and electronic property of graphene. We propose a novel approach to synthesize the nitrogen-doped graphene via thermal annealing graphene with urea, in which the nitrogen source can be controllably released from the urea by varying the annealed temperature and time. The doped N content and the configuration N as well as the thermal stabilities are also evaluated with X-ray photoelectron spectroscopy and Raman spectra. Electrical measurements indi- cate that the conductivity of doped graphene can be well regulated with the N content. The method is expected to produce large scale and controllable N-doped graphene sheets for a variety of potential applications.

关键词： Graphene Doping Conductivity X-ray photoelectron spectroscopy Ramanspectrum

A modified method for simulating non-stationary multi-point earthquake ground motion

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 201-211页

作者： li Minggao,li xin and Zhou jing State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian China

A spectral-representation-based algorithm is proposed to simulate non-stationary and stochastic processes with evolutionary power,according to a prescribed non-stationary cross-spectral density matrix. Non-stationary multi-point seismic ground motions at different locations on the ground surface are generated for use in engineering applications. First,a modified iterative procedure is used to generate uniformly modulated non-stationary ground motion time histories which are compatible with the prescribed power spectrum. Then,ground motion time histories are modeled as a non-stationary stochastic process with amplitude and frequency modulation. The characteristic frequency and damping ratio of the Clough-Penzien acceleration spectrum are considered as a function of time in order to study the frequency time variation. Finally,two numerical examples are presented to validate the efficiency of the proposed method,and the results show that this method can be effectively applied to the dynamic seismic analysis of long and large scale structures.

关键词： multi-support excitation spatial correlation power spectrum-compatibility non-stationary ground motion simulation

Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

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Rare Metals 2024年第7期43卷 3107-3117页

作者： xin-Yang liu jing-Wei liu Gang li jing-Xiang Zhao College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025China

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and *** this work,by means of the density functional theory(DFT) calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM_(1-4)@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions(OER),oxygen reduction reactions(ORR) and hydrogen evolution reactions(HER).The computed results reveal that the Pd_(2),Pd_(4) and Pt_(1) anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd_(1) and Pt_(2)@graphdiyne can exhibit excellent catalytic performance for water splitting(OER/HER) with the overpotentials of 0.55/0.17 and 0.43/0.03 *** addition,Ni_(1) and Pd_(3) anchored GDY can perform as bifunctional catalysts for metal-air cells(OER/ORR) and fuels cells(ORR/HER) with the overpotentials of 0.34/0.32 and 0.42/0.04 V,***,by precisely controlling the numbers of atoms in clusters,the TM_(1-4) anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

Pituitary apoplexy complicated with subarachnoid hemorrhage caused by incidentaloma following a head injury:case report

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Chinese Medical Journal 2007年第24期120卷 2341-2343页

作者： BAO Yi-jun li xin-guo jing Zhi-tao OU Shao-wu WU An-hua WANG Yun-jie Department of Neurosurgery First Hospital of China Medical University Shenyang 110001 China

Plituitary apoplexy is a rare clinical syndrome caused by acute enlargement of pituitary adenomas, which may be secreting or nonfunctioning, and symptomatic or asymptomatic, resulted from hemorrhage or infarction. Subarachnoid hemorrhage （SAH） is an unusual presentation in patients with pituitary apoplexy, and that following a head injury is more infrequently reported. Here, we report a case of pituitary apoplexy complicated with subarachnoid hemorrhage caused by an incidentaloma after head trauma in an aged man, who experienced a spontaneous regression of the tumor.

关键词： incidentaloma pituitary apoplexy subarachnoid hemorrhage

A Dietary Supplement jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides

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Chinese Journal of Integrative Medicine 2024年第4期30卷 330-338页

作者： MA jing SUN Bo TE li-ger HUANG xin ZUO xin HAN Xiao-ke WANG Shu-song Hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive HealthHebei Reproductive Health HospitalShijiazhuang(050071)China Graduate School of Hebei Medical University Shijiazhuang(050017)China School of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang(050024)China xingtai Infertility Specialist Hospital XingtaiHebei Province(054000)China

Objective To determine the possible protective effects of jinghuosu,a dietary supplement(DS),on tripterygium glycosides(TG)-induced reproductive system injury in rats and its underlying *** A reproductive damage model was established in rats by feeding of ***-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table(n=7 in each):control(C)group,model(M)group,DS group and L-carnitine(LC)*** in M,DS and LC groups received 40 mg/kg TGs *** from the 5th week,after administration of TGs for 4 h every day,rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC,respectively,for protective treatment over the next 4 *** in Group C continued to receive the control ***-eosin staining was used for histopathological analysis of rat testicular ***-linked immunosorbent assay was performed to measure alkaline phosphatase(ALP),lactate dehydrogenase,alcohol dehydrogenase,total antioxidant capacity(T-AOC),superoxide dismutase,glutathione peroxidase(GSH-Px),and malondialdehyde(MDA)*** assay was used to determine the serum testosterone *** real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant *** Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA(Plity,and serum testosterone,serum zinc,testicular zinc,Zrt-,Irt-like protein 1,ALP,luteinizing hormone(LH)receptor,steroidogenic acute regulatory protein,Cytochrome P450 family 11 subfamily A member 1,3β-hydroxysteroid dehydrogenase 1 T-AOC,GSH-Px,nuclear factor erythroid 2-related factor 2,heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1 levels decreased following TG

关键词： dietary supplement jinghuosu tripterygium glycosides reproductive damage infertility

GAN-DIRNet:A Novel Deformable Image Registration Approach for Multimodal Histological Images

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Computers, Materials & Continua 2024年第7期80卷 487-506页

作者： Haiyue li jing Xie jing Ke Ye Yuan Xiaoyong Pan Hongyi xin Hongbin Shen Institute of Image Processing and Pattern Recognition Shanghai Jiao Tong Universityand Key Laboratory of System Control and Information ProcessingMinistry of Education of ChinaShanghai200240China Department of Pathology Ruijin HospitalShanghai Jiao Tong UniversitySchool of MedicineShanghai200025China Department of Computer Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China Global Institute of Future Technology Shanghai Jiao Tong UniversityShanghai200240China

Multi-modal histological image registration tasks pose significant challenges due to tissue staining operations causing partial loss and folding of *** neural network(CNN)and generative adversarial network(GAN)are pivotal inmedical image ***,existing methods often struggle with severe interference and deformation,as seen in histological images of conditions like Cushing’s *** argue that the failure of current approaches lies in underutilizing the feature extraction capability of the discriminator *** this study,we propose a novel multi-modal registration approach GAN-DIRNet based on GAN for deformable histological image *** begin with,the discriminators of two GANs are embedded as a new dual parallel feature extraction module into the unsupervised registration networks,characterized by implicitly extracting feature descriptors of specific ***,modal feature description layers and registration layers collaborate in unsupervised optimization,facilitating faster convergence and more precise ***,experiments and evaluations were conducted on the registration of the Mixed National Institute of Standards and Technology database(MNIST),eight publicly available datasets of histological sections and the Clustering-Registration-Classification-Segmentation(CRCS)dataset on the Cushing’s *** results demonstrate that our proposed GAN-DIRNet method surpasses existing approaches like DIRNet in terms of both registration accuracy and time efficiency,while also exhibiting robustness across different image types.

关键词： Histological images registration deformable registration generative adversarial network cushing’s disease machine learning computer vision

Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

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International Journal of Extreme Manufacturing 2024年第1期6卷 277-294页

作者： Bo Yao Nan Kang Xiangyu li Dou li Mohamed EL Mansori jing Chen Haiou Yang Hua Tan xin lin State Key Laboratory of Solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et Metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic *** essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and *** this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)*** evolution and phase selection of Nd-Fe-B magnets were then clarified in *** results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase *** terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is *** the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B ***,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic ***,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic perfor

关键词： laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

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