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Energy storage performance and phase transition under high electric field in Na/Ta co-doped AgNbO_(3)ceramics

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Journal of Materiomics 2023年第1期9卷 19-26页

作者： Mingyuan zhao Jing Wang Hao Yuan Zehan Zheng Lei zhao Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College Physics Science and TechnologyHebei UniversityBaoding071002China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China

Lead-free antiferroelectric ceramics with high energy storage performance show great potential in pulsed power ***,poor breakdown strength and antiferroelectric stability are the two main drawbacks that limit the energy storage performance of antiferroelectric ***,highquality(Ag_(1-x)Na_(x))(Nb_(1-x)Ta_(x))O_(3)ceramics were prepared by the tape casting *** breakdown strength was greatly improved as a result of the high density and fine grains,while the antiferroelectric stability was enhanced owning to the M2 *** from the synergistic improvement in breakdown strength and antiferroelectric stability,(Ag_(0.80)Na_(0.20))(Nb_(0.80)Ta_(0.20))O_(3)ceramic reveals a benign energy storage performance of W_(rec)=5.8 J/cm^(3)and h=61.7%with good temperature stability,frequency stability and cycling *** is also found that the high applied electric field can promote the M2-M3 phase transition,which may provide ideas to improve the thermal stability of the energy storage performance in AgNbO_(3)-based ceramics.

关键词： Antiferroelectric ceramics AgNbO_(3)-based ceramics Phase transition Tape casting process

Diffusion and Relaxation Dynamics of Supercooled Polymer Melts

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Chinese Journal of Polymer Science 2018年第10期36卷 1187-1194页

作者： deng Pan zhao-Yan Sun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters College of Physical Science and Technology Yili Normal University Yining 835000 China

The dynamic properties of polymer melts are investigated in the range of normal liquid regime to the supercooled liquid regime. The polymer is modeled as a coarse-grained bead-spring model with chain length ranging from 5 to 160. The mean squared displacement and non-Gaussian parameter are used to describe the self diffusion of polymer beads. We find slow dynamics with decreasing temperature and increasing chain length. The time evolution of non-Gaussian parameters shows two peaks （or one peak one shoulder） in the a-relaxation time, τa, regime and sub-diffusion time regime, respectively, where the first primary peak indicates the dynamic heterogeneity stemmed from the motion of beads, and the secondary peak is the result of correlated motion along a polymer chain. Moreover, the relaxation of polymer beads shows clear two-step decay in supercooled melts and the dynamics shows growing heterogeneity with decreasing temperature. As chain length is increased, a peak of the dynamic susceptibility occurs, and the peak height, x＊4, increases and then reaches a plateau. The curves of the height of the first peak of a2, a2＊, versus τa and the curves of x＊4 versus τa follow two master curves for different chain lengths. Our results indicate the similarity of dynamic heterogeneity dominated by the motion of single bead even the chain length is different. It is interesting to find that the Stokes-Einstein （SE） relation between ra and diffusion coefficient D, D-rq 1, is highly length-scale dependent. The SE relation breaks down in both normal melts regime and supercooled regime at large magnitude of wave vectors, attributed to the non-Brownian motion arising from the chain connectivity and growing heterogeneity due to supercooling. However, the SE relation is reconstructed when the probing length scale is large （at small magnitude of wave vectors）. Our results show a hierarchical physical picture of the supercooled polymeric dynamics.

关键词： Supercooled polymer melt Molecular dynamics simulation Diffusion Relaxation

Assessment of deep groundwater over-exploitation in the North China Plain

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Geoscience Frontiers 2011年第4期2卷 593-598页

作者： Jiansheng Shi zhao Wang zhaoji Zhang Yuhong Fei Yasong Li feng＇e Zhang Jingsheng Chen Yong Qian Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences Shigang Street 406 ShijiazhuangHebei 050061 China

A series of environmental—geological problems have been caused by over-exploitation of deep groundwater（i.e.,confined aquifer water） in the North China *** order to better understand the status of deep groundwater over-exploitation and the resultant environmental—geological problems on a regional scale,the over-exploitation of groundwater has been assessed by way of the groundwater exploitation potential coefficient（i.e.,the ratio of exploitable amount of deep groundwater to current exploitation）, cumulative land subsidence,and long-term average lowering rate of the groundwater *** is a good correlation among the results calculated by the different *** a regional scale,deep groundwater has been over-exploited and there is no further exploitation potential under the current *** groundwater exploitation degree index takes the exploitation in 2003 as the reference for the calculations, so the results mainly reflect the degree of current groundwater *** results of over-exploitation of deep groundwater obtained by land subsidence data and long-term average rate of depression of the water table mainly reflect environmental—geological problems caused by exploitation of deep groundwater.

关键词： North China Plain deep groundwater Assessment of over-exploitation Land subsidence Water table depression

Non-parametric reconstruction of growth index via Gaussian processes

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Science China(Physics,Mechanics & Astronomy) 2019年第9期62卷 110-119页

作者： zhao-Yu Yin Hao Wei School of Physics Beijing Institute of Technology

The accelerated cosmic expansion could be due to dark energy within general relativity(GR), or modified gravity. Differentiating between them using both the expansion history and growth history has attracted considerable attention. In the literature, the growth index γ has been found useful to distinguish these two scenarios. This work aims to consider the non-parametric reconstruction of the growth index γ as a function of redshift z from the latest observational data as of July 2018 via Gaussian processes. We found that f(R) theories and dark energy models within GR(especially ΛCDM) are inconsistent with the results in the moderate redshift range far beyond 3σ confidence level. A modified gravity scenario different from f(R) theories is favored. However, these results can also be due to other non-trivial possibilities in which dark energy models within GR(especially ΛCDM) and f(R) theories may still survive. In all cases, our results suggest that new physics is required.

关键词： cosmology dark energy modified gravity growth index Gaussian processes

基于三维地球模型的中国大陆重力潮汐因子研究

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地球与行星物理论评（中英文） 2025年第1期56卷 83-93页

作者：王振宇赵倩中国地震局地震预测研究所北京100036

潮汐现象是地球对日、月等星体引力的响应,重力潮汐因子对于揭示地球内部结构具有重要作用.中国地震局、中国科学院等自20世纪80年代开始布设首批重力仪,用于研究中国大陆固体潮空间分布特征,到目前为止已建成超过50个台站的重力观测网... 详细信息

潮汐现象是地球对日、月等星体引力的响应,重力潮汐因子对于揭示地球内部结构具有重要作用.中国地震局、中国科学院等自20世纪80年代开始布设首批重力仪,用于研究中国大陆固体潮空间分布特征,到目前为止已建成超过50个台站的重力观测网络.本研究利用该网络的重力潮汐因子观测结果,结合考虑了横向非均匀效应的潮汐理论和三维地球模型,构建了中国大陆及周边地区的重力M_(2)、O_(1)因子分布模型.基于微扰理论,本研究发现P波速度扰动、S波速度扰动、密度扰动及综合效应对重力M_(2)因子影响的幅值范围分别为-0.12%至0.14%、-0.19%至0.17%、-0.08%至0.06%和-0.09%至0.11%(对O1因子的影响为-0.13%至0.28%、-0.27%至0.15%、-0.12%至0.10%和-0.15%至0.05%),影响最显著的区域为喜马拉雅造山带(负值)和华夏古陆东南缘(正值),体现了这些地区的特殊构造.本研究利用最小二乘配置方法对重力潮汐因子的理论值与实测值进行了融合,发现中国大陆及周边地区的重力M_(2)因子幅值范围为1.130至1.175,总体呈现周围低、中心高的特征.重力O1因子幅值范围为1.145至1.195,总体呈现从西北向东南逐渐升高的特征.以上结果可为中国大陆及周边地区重力潮汐因子、地球模型等相关研究提供参考.

关键词：重力潮汐因子三维地球模型数据融合

Lattice Strain Induced by Ion Implantation in AlGaAs/AlGaInAs Quantum Well Samples

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Chinese Physics Letters 2002年第4期19卷 599-601页

作者： Liu Pi-Jun Xia Yue-Yuan Liu Xiang-Dong Yuan feng-Po Pan Jiao-Qing Xue Cheng-Shan Li Yu-Guo zhao Ming-Wen Ma Yu-Chen department of Physics Shandong University Ji'nan 250100 Hebei Semiconductor Research Institute Shijiazhuang 050002 Institute of Crystal Materials Shandong University Ji'nan 250100 Institute of Semiconductor Shandong Normal University Ji'nan 250100

Si+ ions of 350keV have been implanted into AlGaAs/AlGaInAs quantum well samples in the dose range from 5×1013cm-2to 5×1014cm-2. The Raman spectra and high resolution x-ray diffraction (HRXRD) were measured from these implanted samples as well as the non-implanted sample. In the implanted layers the average strain which was evaluated by HRXRD increases with the implantation doses and varies from 0.0011 to 0.0029. The quantum well interface intermixing effect and compositional modification are also observed from HRXRD. At the higher doses, an abnormal annealing procedure takes place and it partly removes damage, but the strain remains almost unchanged in the epilayers.

关键词： Aluminum gallium arsenide

多枝金纳米颗粒催化氢化物还原反应的无标记SERS监测

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聊城大学学报（自然科学版） 2025年第1期38卷 59-67页

作者：王靖淞赵兴娟山东建筑大学理学院山东济南250101

表面增强拉曼散射(SERS)技术,作为一种极具潜力的分子光谱手段,正引领着贵金属纳米粒子在催化化学反应领域的深入研究。其中,金纳米颗粒(AuNP)作为催化剂,在催化氢化物参与的化学反应中展现出卓越的催化性能。通过化学吸附将4-硝基硫酚... 详细信息

表面增强拉曼散射(SERS)技术,作为一种极具潜力的分子光谱手段,正引领着贵金属纳米粒子在催化化学反应领域的深入研究。其中,金纳米颗粒(AuNP)作为催化剂,在催化氢化物参与的化学反应中展现出卓越的催化性能。通过化学吸附将4-硝基硫酚分子(4-NTP)覆盖于AuNP纳米探针表面,通过在纳米探针表面修饰三种不同分枝的多枝金纳米颗粒(短枝纳米星、长枝纳米星和纳米树莓),用于4-硝基硫酚向4-氨基硫酚(4-NTP)的高效催化转化。利用SERS技术监测反应过程,捕捉金属纳米星与溶液界面处分子结构的变化,研究AuNP界面反应的动力学过程。研究结果表明,AuNP的催化活性与其尖端的尖锐程度和分枝的数量密切相关。研究结果为从分子层面理解并优化催化机制提供了借鉴。

关键词：金纳米颗粒表面增强拉曼散射纳米纤维催化活性

Syntheses and Insecticidal Activity of Spirocyclic Tetronic Acid derivatives Containing Oxime Ether Moiety

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Chemical Research in Chinese Universities 2020年第5期36卷 810-815页

作者： zhao Yang CHENG Jingli XIE Zhengang FANG Shaowei zhao Jinhao Ministty of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insert Institute of Pesticide and Environmental ToxicologyZhejiang UniversityHangzhou 310058P.R.China

In order to develop novel spirocyclic tetronic acid lead compounds,a series of new spirocyclic tetronic acid derivatives containing oxime ether moiety was synthesized and *** stmctures of 16 target compounds were characterized by lH NMR spectra,13C NMR spectra and high-resolution mass spectrometer(HRMS).Preliminary bioassays indicated that most of the title compounds displayed excellent insecticidal activity against Aphis fabae and Nilapmyata lugens at 100 mg/*** particular,compound 6k showed the similar activity(LC50=6.87 mg/L)against *** as the spirotetramat(LC50=4.56 mg/L)and had better efIects(LC50=l.64 mg/L)against *** in comparison with spirotetramat(LC5o=7.90 mg/L).The study showed that compound 6k exhibited more promising and broad-spectrum insecticide activity and may serve as a new insecticidal agent for sucking pests.

关键词： Spirocyclic tetronic acid derivative Insecticidal activity Oxime ether moiety

Linkage analysis of chromosome 14 and essential hypertension in Chinese population

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Chinese Medical Journal 2005年第23期118卷 1939-1944页

作者： zhao Wei-yan HUANG Jian-feng GE Dong-liang SU Shao-yong LI Biao GU Dong-feng Division of Population Genetics and Prevention CardiovascularInstitute Fuwai Hospital Peking Union Medical College andChinese Academy of Medical Sciences Beijing 100037 China Institute of Biophysics Chinese Academy of Sciences Beijing100101 China （ National Human Genome Center at Beijing Beijing 100176 China

Background Hypertension is a complex biological trait that influenced by multiple factors. The encouraging results for hypertension research showed that the linkage analysis can be used to replicate other studies and discover new genetic risk factors. Previous studies linked human chromosome 14 to essential hypertension or blood pressure traits. With a Chinese population, we tried to replicate these findings.Methods A linkage about lO centi Morgen analysis and exclusion was performed with the scan was performed on chromosome 14 with 14-microsatellite markers with a density of （cM） in 147 Chinese hypertensive nuclear families. Muhipoint non-parametric linkage mapping were performed with the GENEHUNTER software, whereas quantitative analysis variance component method integrated in the SOLAR package.Results In the qualitative analysis, the highest non-parametric linkage score is 1.0 （ P=0.14） at DI4S261 in the single point analysis, and no loci achieved non-parametric linkage score more than 1.0 in the multipoint analysis. Maximum-likelihood mapping showed no significant results, either. Subsequently the traditional exclusion criteria of the log-of-the-odds score-2 were adopted, and the chromosome 14 with λs≥ 2.4 was excluded. In the quantitative analysis of blood pressure with the SOLAR software, two-point analysis and multipoint analysis suggested no evidence for linkage occurred on chromosome 14 for systolic and diastolic blood pressure.Conclusion There was no substantial evidence to support the linkage of chromosome 14 and essential hypertension or blood pressure trait in Chinese hypertensive subjects in this study.

关键词： essential hypertension linkage analysis chromosome 14 Chinese