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2008年汶川MW7.9地震可能不是由紫坪铺水库诱发的证据

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世界地震译丛 2018年第3期49卷 183-194页

作者： K.Deng s.y.zhou R.Wang R.Robinson C.P.Zhao W.Z.Cheng 宋肖汉北京大学地球与空间科学学院

根据库仑破裂准则,切应力、正应力或是孔隙压力的变化都会对地震的发生产生影响。水库周边地震活动的异常增加现象通常会被认为是由水库蓄水所引起的,因为水库蓄水会增大水库周边地区的地下孔隙压力和库仑应力,从而促使附近的断层发生... 详细信息

根据库仑破裂准则,切应力、正应力或是孔隙压力的变化都会对地震的发生产生影响。水库周边地震活动的异常增加现象通常会被认为是由水库蓄水所引起的,因为水库蓄水会增大水库周边地区的地下孔隙压力和库仑应力,从而促使附近的断层发生破裂。为了研究距离龙门山断层仅有几百米远的紫坪铺水库大坝对2008年5月12日发生的汶川M W7.9地震产生了多大的影响,我们计算了紫坪铺水库2005年10月蓄水以来引起的库仑应力的变化。此外我们还分析了当地地震活动变化和库仑应力变化之间的联系。计算得出的库仑应力变化结果和观察到的地震活动的分析结果均表明:紫坪铺水库活动诱发汶川M W7.9大地震的几率是非常小的。紫坪铺水库的蓄水活动仅可能导致水库附近震源深度小于5km的浅层地震活动频率的增加。

关键词：紫坪铺水库地震活动汶川诱发库仑应力变化水库蓄水证据破裂准则

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Recent development in electrode design for wide-temperature supercapacitors

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science China Chemistry 2025年第1期68卷 96-117页

作者： Jianhong Liu Qiang zhou yuxiao Lin Xinsheng Zhao Guangmin zhou Xiaoxiao Li school of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley shenzhen Institute & Tsinghua shenzhen International Graduate school Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(sCs). The active electrode is one of the most important parts of sC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the sC electrodes aimed for room-temperature application, the sC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of sC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature sC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature sC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature sCs are also proposed.

关键词： supercapacitor wide-temperature electrode design active materials

Exercise preconditioning alleviates ischemia-induced memory deficits by increasing circulating adiponectin

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Neural Regeneration Research 2025年第5期20卷 1445-1454页

作者： Meifeng Zheng Borui Zhang sonata s y yau Kwok-Fai so Li Zhang Haining Ou Department of Rehabilitation Medicine Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Medicine The Fifth Clinical College of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Key Laboratory of CNs Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation sciences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina state Key Laboratory of Brain and Cognitive science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Center for Exercise and Brain science School of PsychologyShanghai University of SportShanghaiChina Neuroscience and Neurorehabilitation Institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina

Cerebral ischemia is a major health risk that requires preventive approaches in addition to drug *** exercise enhances neurogenesis and synaptogenesis,and has been widely used for functional rehabilitation after *** this study,we determined whether exercise training before disease onset can alleviate the severity of cerebral *** also examined the role of exercise-induced circulating factors in these *** mice were subjected to 14 days of treadmill exercise training before surgery for middle cerebral artery *** found that this exercise pre-conditioning strategy effectively attenuated brain infarct area,inhibited gliogenesis,protected synaptic proteins,and improved novel object and spatial memory *** analysis showed that circulating adiponectin plays a critical role in these preventive effects of *** activation of adiponectin receptors by Adipo Ron mimicked the effects of exercise,while inhibiting receptor activation abolished the exercise *** summary,our results suggest a crucial role of circulating adiponectin in the effects of exercise pre-conditioning in protecting against cerebral ischemia and supporting the health benefits of exercise.

关键词： adiponectin cerebral ischemia exercise pre-conditioning hippocampus memory function middle cerebral artery occlusion prefrontal cortex synaptic proteins treadmill exercise

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Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-Lei zhou siwei Wang yong Chen College of Chemistry and Materials science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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Fine-tuning the spatial allocation of phytohormones for smart canopy, smart breeding, and smart agriculture

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science China Life sciences 2025年第1期68卷 309-310页

作者： Tao zhou Lin Li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University HuBei Hongshan Laboratory

The dual challenges of global climate change and population growth have increased demand for higher crop yields per unit area. The innovative technology of smart agriculture aims to synergize breeding, cultivation, and production through the application of biological and informatics technologies. Historically, the “Green Revolution” introduced semidwarf varieties of certain key crops by utilizing mutations affecting gibberellin pathways, which significantly increased planting densities and yields.

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Microstructure and Wear/corrosion Resistance of stainless steel Laser-alloyed with Mn+W_(2)C, Mn+NiWC and Mn+siC

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Journal of Wuhan University of Technology(Materials science) 2025年第1期40卷 283-294页

作者： zhou Rui DIAO Xiaogang sUN yixin school of Metallurgical Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China CITIC Heavy Cast Iron Industry Co. Ltd.Luoyang 417039China

In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LsA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+siC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed *** evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were *** indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LsA with Mn+W_(2)C and Mn+NiWC while siC totally dissolved into the high Mn matrix when adding Mn+*** as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C *** improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.

关键词： laser surface alloying stainless steel carbide type microstructure wear and corrosion resistance

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Distributed fiber optic sensing system for vibration monitoring of 3D printed bridges

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Optoelectronics Letters 2025年第1期21卷 28-34页

作者： ZHAO shuai zhou Ran LUO Mingming LIU Jianfei LIU Xiongfei zhou Tao school of Electronic Information Engineering Hebei University of Technology Tianjin Key Laboratory of Electronic Materials and Devices school of Civil Engineering and Transportation Hebei University of Technology Tianjin Jinhang Institute of Technical Physics

The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities, including design, construction, and maintenance of bridges, tunnels, ports and other infrastructures. In this paper, a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment, covering a vibration frequency from 5 Hz to 25 kHz. The sensing fiber was arranged as an s type layout on the bridge to recognize the standing state, windblown disturbance, and walking vibration. Moreover, the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences, respectively. The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge, which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.

关键词： spinning (fibers)

Controlled cationic ring-opening polymerization of L-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

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science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian Wang Zijing zhou Bin Wang yuesheng Li Tianjin Key Laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice sN2 substitution and configuration-inversion （s→R→s） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich polylactide

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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science China Earth sciences 2025年第1期68卷 62-73页

作者： Xin LI yibo zhou Tao ZHAO Xingjian HE yanhong PAN state Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy