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Synthesis,Crystal Structure and Quantum Chemical Investigation of Bis-Schiff Base Compounds derived from2-phenyl-1,2,3-triazole-4-carboxaldehyde with Diamine

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Chinese Journal of Structural Chemistry 2008年第5期27卷 616-621页

作者： XIE Ling LIU Gang wang Yan wang Ji-de CHEN jun-Feng department of Chemistry Key Laboratory of Oil ＆ Gas Fine Chemicals Ministry of Education Xinjiartg University Urumqi 830046 China

Two new schiff base N,N＇-bis（（2-phenyl-2H-1,2,3-triazol-4-yl）methylene）-1,3-propanediamine （1） and N,N＇-bis（（2-phenyl-2H-1,2,3-triazol-4-yl）methylene） -1,4-butanediamine （2） were synthesized by condensation of 2-phenyl-1,2,3-triazole-4-carboxaldehyde with diamine, and characterized by elemental analysis, IR, IH NMR and MS spectra. Their crystal structures were determined by X-ray single crystal diffraction. Both crystals belong to the monoclinic system, space group P21/c. For compound 1（C21H20N8, Mr=384.45）： a = 16.314（3）, b =5.7168（11）, c = 21.316（4） A, β = 105.3（2）°, Z = 4, V = 1917.6（7） A^3, de =1.332 g/cm^3, F（000） = 808,μ = 0.086 mm 1, R = 0.0533 and wR = 0.1460; for compound 2 （C22H22N8, Mr=398.48）： a = 8.6156（17）, b = 5.2964（11）, c = 22.665（5）A, β = 100.54（3）°, Z = 2, V = 1016.8（4） A^3, de= 1.302 g/cm^3, F （000） = 420, μ = 0.083 mm^-1, R = 0.0373 and wR = 0.1155. Based on the crystal data, quantum chemistry calculation was performed on the two title compounds by means of Gaussian 98 program. The molecular orbital energies and atomic net charges population were obtained. Furthermore, we antilyzed their active atoms. The investigation can serve as a theoretical guide to study the synthesis and activity of the title compounds.

关键词： schiff base crystal structure quantum chemical calculation

Influence of NaCI on Cathode Performance of Solid Oxide Fuel Cells

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Chemical Research in Chinese Universities 2013年第4期29卷 747-750页

作者： LIU Run-ru wang de-jun LENG Jing College of Science College of Continuing Education Changchun University Changchun 130022 P. R. China College of Basic Sciences Changchun University of Technology Changchun 130012 P. R. China

degradation induced by sodium chloride in air was investigated for （La0.8Sr0.2）0.98MnO3（LSM） and ***3（LSCF） cathodes in solid oxide fuel cells（SOFC）. Cell performance was measured by volatilizing NaC1 to be supplied to the cathode at a constant current density of 200 mA/em2 for up to 100 h. At 800℃, an exposure of the cathode to 30 mg/L NaC1 caused negligible degradation of LSM at least for 100 h. Slight change in the composition of the cathode materials was observed which may imply the gradual degradation of cell performance for the long-term. In addition, cell performance degradation was compared between 700℃ and 900℃, being poi- soned by 30 mg/L NaCI. degradation was negligible for LSM cathode, while LSCF cathode showed slightly poor to-lerance at 700℃ due to the decomposition of the cathode material. Further studies should be done to clarify the long-term influence of NaCI on cathode performance.

关键词： NaC1 degradation Cathode Solid oxide fuel cell(SOFC)

Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-Li wang Wen-jun Huang de-Li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： deep well Casing integrity Casing wear Casing corrosion Burst strength

Synthesis of Small-sized Coesite Under Lower Pressure

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Chemical Research in Chinese Universities 2010年第3期26卷 352-354页

作者： wang de-jun LIU Xiao-mei ZHU Cheng-jun YAN Duan-ting LIU Fu-lin SU Wen-hui State Key Laboratory of Superhard Materials College of Physics Jilin University Changchun 130021 P R. China Adult Education College of Changchun University Changchun 130022 P. R. China Center of the Condensed Matter Science and Technology Harbin Institute of Technology Harbin 150001 P R. China International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 P. R. China

With the help of high-energy mechanical milling and a-SiO2 as the initial material, we investigated the synthesis of coesite at a high temperature and high pressure under the condition of adding a certain amount of hard Fe filling. The synthetic samples were measured by XRD and Raman spectroscopy. The results show that a small amount of small-sized coesite can be obtained under 2.5 GPa and 973 K.

关键词： Coesite High temperature and high pressure High-pressure micro-area a-SiO2

China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： Wen-jun Tu Long-de wang 无 department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable *** to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a ***,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in *** the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,***“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from *** from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted dur

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

Mechanical properties and microstructure of Mg-treated and Catreated industrial H13 steel after quenching and tempering

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Journal of Iron and Steel Research International 2024年第8期31卷 1987-2001页

作者： jun-ying Yue Dong Hou de-yong wang Tian-peng Qu Xiang-long Li jun Tian School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The effect of magnesium treatment and calcium treatment on the microstructure and mechanical properties of industrial H13 steel after quenching and tempering was *** impact toughness and tensile tests were mainly carried out,and the microstructure was observed by scanning electron microscopy,electron backscattered diffraction,and X-ray *** results show that magnesium treatment is still feasible in industrial *** is mainly manifested in the refinement of lath martensite and *** with calcium treatment,the prior austenite grains and carbides size of industrial H13 steel treated with magnesium decreased by 3.17μm after *** quenching and tempering,the carbides(especially V-rich carbides)in Mg treatment obviously spheroidized and distributed uniformly and increased in quantity *** lath martensite size is reduced from 2.45 to 2.31μ*** suggests that magnesium treatment was able to yield smaller grains and more evenly distributed ***,the impact toughness,yield strength,and ultimate tensile strength of industrial H13 steel with magnesium treatment increased by 28%,65.5 MPa and 123.7 MPa,*** increment of strength mainly comes from dislocation strengthening,grain refinement strengthening,and precipitation strengthening,among which precipitation strengthening accounts for the largest proportion.

关键词： Industrial H13 steel Mg treatment Heat treatment Carbide-Mechanical property

Influence of Carbon-doped Content on Formation Conditions of Coesite

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Chemical Research in Chinese Universities 2009年第6期25卷 920-923页

作者： wang de-jun LIU Xiao-mei ZHU Cheng-jun YAN Duan-ting LIU Yi-xin SUN Ying LIU Fu-lin SU Wen-hui State Key Laboratory of Superhard Materials College of Physics Jilin University Changchun 130021 P. R. China Adult Education College Changchun University Changchun 130022 P. R. China Center of the Condensed Matter Science and Technology Harbin Institute of Technology Harbin 150001 P. R. China International Center for Material Physics Chinese Academy of Sciences Shenyang 110015 P. R. China

The mixtures of a-quartz and graphite powder with different mass ratios were, respectively, high-energetically mechanically milled and then treated under high pressure and high temperature. The influences of carbon content on the synthesis conditions of coesite were investigated. The experimental products were characterized by XRD, TEM, and Raman spectrometry. The results show that the existence of carbon can obviously inhibit the formation of coesite, and the higher the carbon content of the initial material, the higher the pressure for forming coesite.

关键词： Coesite High pressure Mechanical ball-milling α-SiO2 Graphite

Vision-based survey method for extraordinary loads on buildings

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 815-831页

作者： Yang LI jun CHEN Pengcheng wang College of Civil Engineering Tongji UniversityShanghai 200092China China United Engineering Co.Ltd. Hangzhou 310052China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Engineering Structure Safety Shanghai Research Institute of Building Sciences Co.Ltd.Shanghai 200032China

The statistical modeling of extraordinary loads on buildings has been stagnant for decades due to the laborious and error-prone nature of existing survey methods,such as questionnaires and verbal *** study proposes a new vision-based survey method for collecting extraordinary load data by automatically analyzing surveillance *** this purpose,a crowd head tracking framework is developed that integrates crowd head detection and reidentification models based on convolutional neural networks to obtain head trajectories of the crowd in the survey *** crowd head trajectories are then analyzed to extract crowd quantity and velocities,which are the essential factors for extraordinary *** survey areas with frequent crowd movements during temporary events,the equivalent dynamic load factor can be further estimated using crowd velocity to consider dynamic effects.A crowd quantity investigation experiment and a crowd walking experiment are conducted to validate the proposed survey *** experimental results prove that the proposed survey method is effective and accurate in collecting load data and reasonable in considering dynamic effects during extraordinary *** proposed survey method is easy to deploy and has the potential to collect substantial and reliable extraordinary load data for determining design load on buildings.

关键词： load survey extraordinary load live load object detection multiple-object tracking

A GMM approach in coupling internal data and external summary information with heterogeneous data populations

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Science China Mathematics 2024年第5期67卷 1115-1132页

作者： jun Shao Jinyi wang Lei wang Key Laboratory of Advanced Theory and Application in Statistics and Data Science(East China Normal University) Ministry of EducationShanghai 200062China School of Statistics East China Normal UniversityShanghai 200062China department of Statistics University of Wisconsin-MadisonWI 53706USA School of Statistics and Data Science KLMDASRLEBPS and LPMCNankai UniversityTianjin 300071China

Because of advances in data collection and storage,statistical analysis in modern scientific research and practice now has opportunities to utilize external information such as summary statistics from similar studies.A likelihood approach based on a parametric model assumption has been developed in the literature to utilize external summary information when the populations for external and main internal data are assumed to be the *** this article,we instead consider the generalized estimation equation(GEE)approach for statistical inference,which is semiparametric or nonparametric,and show how to utilize external summary information even when internal and external data populations are not the *** approach is coupling the internal data and external summary information to form additional estimation equations and then applying the generalized method of moments(GMM).We show that the proposed GMM estimator is asymptotically normal and,under some conditions,is more efficient than the GEE estimator without using external summary *** of the asymptotic covariance matrix of the GMM estimators are also *** results are obtained to confirm our theory and quantify the improvements by utilizing external *** example is also included for illustration.

关键词： adjustment for heterogeneity constraint data integration generalized method of moments summarystatistic