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Chemical Research in Chinese Universities 1995年第4期11卷 336-341页

作者： LI Zhi-ru WANG Xiao-peng peng Ji-kang andSUN Chia-chun(Department of Chemistry and Institute of Theoretical Chemistry,Jilin University,Changchun,130023) JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA JILIN UNIV INST THEORET CHEMCHANGCHUN 130023PEOPLES R CHINA

alculations of the nonlinear second-order optical susceptlbilities(β_(ijk))for sub- stituted tl1iophene derivative;with quinoidlike conformation are *** systetems possess small dipole moment;and large differences between dipole mo- ments of ground and first-excited *** optimizations of the molecules investigated were carried out using AM 1 *** calculations were performed using INDO/CI method comboned with a sum-over-states expression for β_(jik). The calculated results sbw that the second-order susceptibility is a function of the na- ture and location of substituents and is larger for disubstituted molecules than monosubstituted molecules. Bipolymeric thiophenemetmne with NH_2/NO_2 groups was calctilated to have a β_μof 79. 920 × 10￣(-30) esu. It was found that the NH_2 and NO_2 groups in above disubstituted molecules are pull-pull groups in ground states,but are usual push-pull groups in the first excited states.

关键词： Nonlinear second-order optical susceptibility INDO/CI,Substituted thiophene derivatives

Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang Yu-kang Lou Lin peng Yuan peng Meng-Meng Wang Ming Zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

A bounding surface visco-plasticity model considering generalized spacing ratio of soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1832-1846页

作者： Xiaosen kang Hongjian Liao Qiangbing Huang Jianbing peng Department of Geological Engineering Chang’an UniversityXi’an710054China Department of Civil Engineering Xi’an Jiaotong UniversityXi’an710049China

The non-unique critical state of soils with time-dependent behaviors is a significant issue in geotechnical engineering ***,previous bounding surface plasticity models cannot predict accurately the non-unique critical state of soils,because the distance between the compression line and critical state line charged by strain-rate effect is basically *** fill this gap,a generalized spacing ratio of soils is defined in the elasto-viscoplastic framework,and a bounding surface visco-plasticity model is formulated and verified,which can consider the generalized spacing ***,the generalized spacing ratio of soils reflects the distance between the compression line and the critical state line of soils with time-dependent ***,the generalized spacing ratio is introduced into an improved anisotropic bounding surface.A new expression of the visco-plastic multiplier is derived by solving the consistency equation of an anisotropic bounding *** the expression,a strain rate index is proposed to account for the strain-rate effect on visco-plastic strain increment,and a visco-plastic hardening modulus is derived to predict the visco-plastic response of soils in overconsolidation *** model is then verified through constant strain rate tests and creep ***,it can capture the non-unique critical states of soils with time-dependent behaviors due to the generalized spacing ratio and the creep rupture of soils due to the visco-plastic multiplier that considers the stress ratio and visco-plastic strain rate.

关键词： Soil Constitutive model Visco-plastic behavior Strain rate Creep Anisotropic

High-entropy Sm_(2)B_(2)O_(7)(B=Ti,Zr,Sn,Hf,Y,Yb,Nb,and Ta) oxides with highly disordered B-site cations for ultralow thermal conductivity

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Journal of Materials Science & Technology 2022年第24期119卷 182-189页

作者： Liang Xu Lei Su Hongjie Wang Hongfei Gao pengfei Guo Min Niu kang peng Lei Zhuang Zhiwei Dai State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

Materials with ultralow thermal conductivity and good thermal stability are of great interest in numerous applications such as energy storage and conversion devices,and thermal insulation *** this work,a family of high-entropy Sm_(2)B_(2)O_(7)(B=Ti,Zr,Sn,Hf,Y,Yb,Nb,and Ta) oxides with highly disordered cations on the B-site has been synthesized by introducing large atomic-size mismatch,mass and charge *** tuning the composition,the high-entropy Sm_(2)B_(2)O_(7) oxides can be engineered from pyrochlore to fluorite structure,accompanied with an order-disorder *** pyrochlore Sm_(2)(Nb_(0.2)Sn_(0.2)Ti_(0.2)Y_(0.2)Zr_(0.2))_(2)O_(7) and fluorite Sm_(2)(Nb_(0.2)Ta_(0.2)Y_(0.2)Yb_(0.2)Zr_(0.2))_(2)O_(7) exhibit low thermal conductivities of 1.35 W·m^(-1)·K^(-1) and 1.23 W·m^(-1)·K^(-1),respectively,indicating their good thermal *** addition,the high-entropy fluorite Sm_(2)(Nb_(0.2)Ta_(0.2)Y_(0.2)Yb_(0.2)Zr_(0.2))_(2)O_(7) also shows average thermal expansion coefficient of 10.2 × 10^(-6)℃^(-1) and high-temperature stability even after thermal exposure at 1600 °C in air for 30 *** results indicate that the high-entropy Sm_(2)B_(2)O_(7)(B=Ti,Zr,Sn,Hf,Y,Yb,Nb,and Ta) can be promising candidates for thermal barrier coatings and thermally insulators.

关键词： High-entropy oxides Atomic sizes mismatch Mass and charge disorder Thermal conductivity Thermal barrier coatings materials

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长龄期混凝土构件强度现场检测对比试验研究

河南科技 2024年第13期51卷 55-60页

作者：康鹏陈顺超刘杰宋帅聂良鹏游鹏升西南林业大学云南昆明650224 云南通衢工程检测有限公司云南昆明650200

【目的】由于受到荷载和环境因素的影响,服役时间较长的混凝土结构劣化现象严重。在不破坏结构且不影响其使用的前提下,及时准确测定混凝土强度对评价桥梁的安全性至关重要。【方法】本研究采用回弹法、超声回弹综合法、后锚固法、钻芯... 详细信息

【目的】由于受到荷载和环境因素的影响,服役时间较长的混凝土结构劣化现象严重。在不破坏结构且不影响其使用的前提下,及时准确测定混凝土强度对评价桥梁的安全性至关重要。【方法】本研究采用回弹法、超声回弹综合法、后锚固法、钻芯法等4种检测方法,在现场检测9个长龄期混凝土构件的混凝土强度,并做对比分析。【结果】回弹法(国家测强曲线)、回弹法(地方测强曲线)、超声回弹综合法(国家测强曲线)、超声回弹综合法(地方测强曲线)、后锚固法与钻芯法的平均误差分别-6.69%、+29.65%、+10.65%、+46.81%、+7.53%。【结论】研究发现,通过采用回弹法与超声回弹综合法得出地方曲线的强度换算值均高于国家曲线的强度换算值。

关键词：长龄期混凝土抗压强度无损检测对比试验

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新型工业化背景下河北省工业互联网平台应用水平探析与路径研究

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新型工业化 2024年第2期14卷 49-57页

作者：袁兵柳杨康鹏平思奇戎彬左璇国家工业信息安全发展研究中心北京100040 河北省电子信息技术研究院河北石家庄050057

工业互联网平台是提升企业数字化竞争力、推动新型工业化发展的重要支撑,其应用水平评价成为衡量我国工业互联网平台高质量发展和规模化应用的重要抓手。本文以河北省工业互联网平台应用水平评价工作为契机,通过工业互联网平台应用推广... 详细信息

工业互联网平台是提升企业数字化竞争力、推动新型工业化发展的重要支撑,其应用水平评价成为衡量我国工业互联网平台高质量发展和规模化应用的重要抓手。本文以河北省工业互联网平台应用水平评价工作为契机,通过工业互联网平台应用推广公共服务平台数据分析得出河北省工业互联网平台应用水平。近年来,河北省工业互联网平台应用水平稳步提升,工业互联网平台应用普及率、工业设备上云率等指标增长态势强劲,但仍存在区域间平台应用水平不均衡、应用价值效益获取滞后、工业知识创新应用难度大、平台应用生态有待完善等问题,本文就此针对性地提出工业互联网平台应用水平提升路径,为相关主体促进工业互联网平台普及应用、加快企业数字化转型步伐提供有益参考。

关键词：工业互联网平台河北省平台应用水平新型工业化

渤海油田小筛管二次防砂井堵塞的动态分析及措施建议

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石化技术 2024年第1期31卷 108-110页

作者：刘召刘国振崔宇丁鹏飞康鹏中海石油(中国)有限公司天津分公司天津300450 中海油能源发展股份有限公司工程技术分公司天津300450

文章通过归纳分析多口小筛管二次防砂井堵塞动态规律,对堵塞源、堵塞机理及堵塞位置进行分析。分析结果表明:二次防砂系统过流面积管理、储层保护、原筛管外环空充填率、原完井系统内的堵塞物处理是小筛管二次防砂完井油井堵塞管理关键... 详细信息

文章通过归纳分析多口小筛管二次防砂井堵塞动态规律,对堵塞源、堵塞机理及堵塞位置进行分析。分析结果表明:二次防砂系统过流面积管理、储层保护、原筛管外环空充填率、原完井系统内的堵塞物处理是小筛管二次防砂完井油井堵塞管理关键。以上结论为小筛管二次防砂井生产异常问题分析提供思路。

关键词：小筛管二次完井油井出砂油井堵塞机理分析动态分析

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Broad-Range Detection of Water Vapor using Cavity Ring-down Spectrometer

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： Bing Chen Jin Wang Yu R.Sun peng kang An-wen Liu Jian-ying Li Xiao-lei He Hefei National Laboratory for Physical Sciences at the Microscale iChem Center University of Science and Technology of China Hefei 230026 China Meteorological Observation Centre China Meteorological Administration Beijing 100081 China

Quantitative measurement of water vapor is essential in many fields including semiconductor industry, combustiondiagnosis,meteorology, and atmospheric studies. We present an optical hygrometer based on cavity ring-down spectroscopy. The instrument is high-vacuum compatible, self-calibrated by using the free-spectral-range of the ring-down cavity made of low-thermal-expansion Invar. Using a single tunable diode laser working at 1.39 μm, detection of trace water vapor in vacuum and in high-purity helium gas, and also determination of humidity at ambient conditions, have been demonstrated. It indicates that the instrument can be used to detect the partial pressure of water vapor in a very broad range from 10?7 Pa to 103 Pa. Such an optical hygrometer can be potentially applied as a primary moisture standard to determine the vapor pressures of water (ice) at low temperatures.

关键词： Cavity ring-down Water vapour Ro-vibrational spectroscopy

Association of frailty with in-hospital outcomes in elderly patients with heart failure

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World Journal of Clinical Cases 2021年第36期9卷 11208-11219页

作者： Yun-peng kang Li-Ying Chen Jia-Jia Zhu Wen-Xian Liu Chang-Sheng Ma Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityNational Clinical Research Center for Cardiovascular DiseasesBeijing 100029China

BACKGROUND Frailty is prevalent in elderly patients with cardiovascular ***,the association between frailty and in-hospital outcomes for elderly patients with heart failure and reduced ejection(HFrEF)remains *** To evaluate the predictive efficacy of frailty,compared with pre-frailty,for adverse events in these *** Elderly patients(≥60 years)with HFrEF were *** was evaluated with the Fried phenotype criteria,and physical performance was evaluated based on handgrip strength and the short physical performance battery(SPPB).The composite incidence of adverse events,including all-cause death,multiple organ failure,cardiac shock,and malignant arrhythmia,during hospitalization was *** Overall,252 elderly individuals with HFrEF[mean age:69.4±6.7 years,male:169(67.0%)]were *** hundred and thirty-five(53.6%)patients were frail and 93(36.9%)were *** patients were older,more likely to be female,to have a lower blood pressure,and to present with left ventricular thrombosis(P all<0.05).Frail patients with HFrEF had a higher incidence of in-hospital mortality(11.9%vs 4.3%,P=0.048).Multivariate analyses showed that female gender(OR=0.422),aging(OR=1.090),poor cardiac functional class(OR=2.167),frailty(OR=2.379),and lower handgrip strength(OR=1.106)were independent predictors of in-hospital adverse events(P all<0.05).CONCLUSION Frailty may be associated with poor in-hospital outcomes for elderly patients with *** influence of frailty on long-term prognosis in these patients deserves further investigation.

关键词： Heart failure with reduced ejection fraction Frailty Elderly Adverse events

Differences in and factors controlling organic matter enrichment in the Ziliujing Formation shale in the Sichuan Basin

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Petroleum Science 2024年第1期21卷 77-86页

作者： peng Li Zhong-Bao Liu He Bi Tao Jiang Rui-kang Bian peng-Wei Wang Xiao-Yu Shang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development Beijing102206China Key Laboratory of Shale Oil/Gas Exploration and Production Technology SINOPECBeijing102206China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China Research Institute of Petroleum Exploration and Development PetroChinaBeijing100083China Chinese Academy of Geological Sciences Beijing100037China No.4 Oil Production Plant in Daqing Oilfield Co Ltd. Daqing163511HeilongjiangChina

Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon *** are two sets of shale,the Dongyuemiao and Da’anzhai Members,in the Ziliujing Formation in the Sichuan *** identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were *** results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the Da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different *** addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early *** made a great difference regarding organic matter accumulation in the two *** general,climate may have played a dominant role in organic matter enrichment in the two sets of shale.

关键词： Lacustrine shale Ziliujing Formation Sichuan Basin Enrichment mechanism of organic matter