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Dynamics and Thermodynamics of Porous HMX-like Material Under Shock

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Communications in Theoretical Physics 2009年第11期52卷 901-908页

作者： XU Ai-Guo ZHANG Guang-Cai ZHANG ping PAN xiao-Fei ZHU Jian-Shi National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009-26 Beijing 100088 China

Strong shock may induce complex processes in porous materials. We use the newly developed materialpoint-method to simulate such processes in an HMX-like material. To pick out relevant information, morphological characterization is used to treat with the temperature map. Via the Minkowski funetional analysis the dynamics and thermodynamics of the shock wave reaction on porous HMX-like material are studied. The geometrical and topological properties of the ＂hot-spots＂ are revealed. Numerical results indicate that, shocks in porous materials are not simple jump states as classically viewed, but rather are a complex sequence of compressions and rarefactions. They cover a broad spectrum of states. We can use coarse-grained description to the wave series. A threshold value of temperature presents a Turing pattern dynamical procedure. A higher porosity is generally preferred when the energetic material needs a higher temperature for initiation. The technique of data analysis can be used to other physical quantities, for example, density, particle velocity, some specific stress, etc. From a series of studies along the line, one may get a large quantity of information for desiring the fabrication of material and choosing shock strength according to what needed is scattered or connected ＂hot-spots＂. PACS numbers： ***, 05 Key words： porous material 70.-a, 05.40.-a, *** shock wave, Minkowski functionals

关键词： porous material shock wave Minkowski functionals

科尔沁沙地南缘樟子松人工林碳汇及对气候因子的响应

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水土保持学报 2024年第4期38卷 236-245页

作者：郎明翰张日升凡胜豪肖巍姜涛卢元李书杨刘思琪辽宁省沙地治理与利用研究所辽宁章古台科尔沁沙地生态系统国家定位观测研究站辽宁阜新123000 辽宁省水利事务服务中心沈阳110003 辽宁省沙地治理与利用研究所国家农业环境彰武观测实验站辽宁阜新123000 辽宁省林业调查规划监测院沈阳110122 内蒙古兴安盟林业科学研究所内蒙古兴安盟137400 敖汉旗林业和草原局内蒙古赤峰024399

[目的]以科尔沁沙地南缘不同初植密度沙地樟子松人工林为研究对象,旨在明晰不同初植密度林分碳储量、碳汇功能及其对气候的响应机制,以便于评估森林生态系统的固碳功能及其适应性管理。[方法]利用林分胸高断面积估算樟子松人工林碳储量... 详细信息

[目的]以科尔沁沙地南缘不同初植密度沙地樟子松人工林为研究对象,旨在明晰不同初植密度林分碳储量、碳汇功能及其对气候的响应机制,以便于评估森林生态系统的固碳功能及其适应性管理。[方法]利用林分胸高断面积估算樟子松人工林碳储量及固碳速率,结合气象因子分析其对温度、降水及蒸发的响应,利用GM(1,1)灰色预测模型对2030年林分碳储量进行预测。[结果]不同初植密度樟子松人工林碳储量和固碳速率年际波动趋势基本一致,碳储量逐年增加,固碳速率曲线呈“U”形。初植密度过低或者过高均降低樟子松人工林碳汇能力;在林龄29年之前,碳汇强度最高林分初植密度为1500~2000株/hm^(2),31~42年林龄的林分最优密度为1000~1200株/hm^(2)。林分碳储量随林分密度增加而增加,且二者拟合公式符合Logarithm方程。樟子松人工林固碳速率对降雨无响应。不同初植密度林分的气温对固碳速率响应模式不同,前一年8月及当年3,5,6,7月平均气温是限制高密度、极高密度樟子松人工林碳汇的主要气候因子;前一年8月及当年3,10月平均气温是限制低密度、中密度樟子松人工林碳汇的主要气候因子。由蒸发和密度林固碳速率相关分析可知,低密度樟子松人工林碳汇对蒸发的响应更为敏感。基于GM(1,1)灰色模型可知,过高或者过低初植密度均降低未来樟子松人工林固碳潜力,固碳速率最优初植林分密度为1772株/hm^(2)。[结论]林分初植密度对沙地樟子松林的碳储量和碳汇及其对气候响应存在明显影响,初植密度调整可能是气候变化下樟子松人工林适应管理的关键措施之一。

关键词：碳储量碳汇 GM(1 1)模型初植密度人工林

Value of early diagnosis of sepsis complicated with acute kidney injury by renal contrast-enhanced ultrasound

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World Journal of Clinical Cases 2019年第23期7卷 3934-3944页

作者： Xiu-Yan Wang Yan-ping Pang Tian jiang Shuo Wang jiang-Tao Li Bao-Min Shi Chen Yu Department of Ultrasound Tongji Hospital of Tongji UniversityShanghai 200065China Department of Nephrology Tongji Hospital of Tongji UniversityShanghai 200065China Department of General Surgery Tongji Hospital of Tongji UniversityShanghai 200065China

BACKGROUND The incidence of acute kidney injury(AKI)in patients with sepsis is high,and the prognosis of patients with septic AKI is *** early diagnosis and treatment of septic AKI is of great significance in improving the prognosis of patients with *** To explore the value of contrast-enhanced ultrasound(CEUS),serum creatinine(Scr),and other indicators in the early diagnosis of septic *** Ninety patients with sepsis during hospitalization at Tongji Hospital of Tongji University were recruited as *** patient was recorded with relevant basic data,clinical indicators,and CEUS *** patients were divided into AKI group and non-AKI group according to the results of renal function diagnosis after 48 *** the 7th day,the renal function of the non-AKI group was re-evaluated and the patients were further divided into AKI subgroup and non-AKI *** differences of the indicators in different groups were compared,and the diagnostic value of each indicator and their combination for septic AKI was *** Systemic inflammatory response score(2.58±0.75),blood lactic acid(3.01±1.33 mmol/L),Scr(141.82±27.19μmol/L),blood urea nitrogen(4.41±0.81mmol/L),and rise time(10.23±2.63 s)in the AKI group were higher than those in the non-AKI *** intensity(PI)(10.78±3.98 dB)and wash in slope(WIS)(1.07±0.53 dB/s)were lower than those in the non-AKI *** differences were statistically significant(P<0.05).The PI(12.83±3.77 dB)and WIS(1.22±0.68 dB/s)in the AKI subgroup were lower than those in the non-AKI subgroup,and the differences were statistically significant(P<0.05).The area under curve(AUC)of Scr for the diagnosis of septic AKI was 0.825 with a sensitivity of 56.76% and a specificity of 100%.The AUCs of WIS and PI(0.928 and 0.912)were higher than those of *** sensitivities were 100%,but the specificities were 71.70% and 75.47%.The AUC of the combination of three indicators for the diagnosis of septic AKI was 0.943,which w

关键词： Sepsis Acute kidney injury Serum creatinine Contrast-enhanced ultrasound Peak intensity Wash in slope

On Ordered Ideals in Ordered Semirings

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Journal of Mathematical Research and Exposition 2011年第6期31卷 989-996页

作者： Ai ping GAN Yang Lan jiang Department of Mathematics Jiangxi Normal University Jiangxi 330022 Po R. China jiangxi Police College Jiangxi 330103 P. R. China

An ordered semiring is a semiring S equipped with a partial order ≤ such that the operations are monotonic and constant 0 is the least element of *** this paper,several notions,for example,ordered ideal,minimal ideal,and maximal ideal of an ordered semiring,simple ordered semirings,etc.,are *** properties of them are given and characterizations for minimal ideals are ***,the matrix semiring over an ordered semiring is *** results obtained in this paper are analogous to the corresponding ones on ordered semigroups,and on the matrix semiring over a semiring.

关键词： ordered semiring ordered ideal simple semiring minimal ideal matrix

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氧化法制备电子级高纯黄磷的实验研究

广州化工 2024年第4期52卷 42-44,78页

作者：杜林姜飞丁哲华超陆平陈锦溢姜占坤湖北兴福电子材料股份有限公司湖北宜昌443007 中国科学院过程工程研究所绿色过程与工程重点实验室北京100190 湖北三峡实验室湖北宜昌443007 济南大学化学化工学院山东济南250022

随着电子工业的发展,对电子级高纯黄磷的需求也日益增加。本文采用氧化法制备电子级高纯黄磷,考察了碘酸和双氧水两种氧化剂,分析了不同的双氧水比例、水洗次数对提纯效果的影响。结果表明,与双氧水对比,碘酸引入了Cu、Ag等金属杂质;经... 详细信息

随着电子工业的发展,对电子级高纯黄磷的需求也日益增加。本文采用氧化法制备电子级高纯黄磷,考察了碘酸和双氧水两种氧化剂,分析了不同的双氧水比例、水洗次数对提纯效果的影响。结果表明,与双氧水对比,碘酸引入了Cu、Ag等金属杂质;经过2倍双氧水和2次水洗后Fe、Ca、Co、Mg等21种杂质均达到电子级高纯水平,且去除了77.9%的As杂质。该研究对电子级高纯黄磷的制备具有重要意义。

关键词：电子级高纯化学品高纯黄磷双氧水氧化

Abnormal Twinning Behavior and Constitutive Modeling of a Fine-Grained Extruded Mg-8.0Al-0.1Mn-2.0Ca Alloy under High-Speed Impact along Various Directions

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Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 281-294页

作者： Fei-Yang Chen Peng-Cheng Guo Zi-Han jiang xiao Liu Tie-Jun Song Chao Xie College of Mechanical and Electrical Engineering Central South University of Forestry and TechnologyChangsha410004China College of Mechanical Engineering and Mechanics Ningbo UniversityNingbo315211China College of Mechanical Engineering Xiangtan UniversityXiangtan411105China College of Material Science and Engineering Hunan University of Science and TechnologyXiangtan411201China

To understand the mechanical and twinning behaviors of a fine-grained extruded Mg-8.0Al-0.1Mn-2.0Ca alloy under high-speed impact,impact tests were carried out using a split Hopkinson pressure bar,and microstructures at strains of 0.05,0.10 and 0.20 were obtained using a series of stop rings manufactured by high-strength *** stress response and twinning behavior are closely related to loading direction and applied strain *** true stress-true strain curves are s-shaped in extrusion direction(ED)and c-shaped in transverse direction(TD),showing apparent anisotropy,while the yield strength is insensitive to loading *** identical strain-rate sensitivity is demonstrated by the stress in ED and ***,de-twinning is apparent as the applied strain increases to 0.20,and it is enhanced with increasing the applied strain *** contrast,the twin density in ED samples is clearly higher than that in TD *** modifying the terms of strain hardening and strain rate hardening in the classical JC model,an optimized model is built,which can accurately predict the stress response behavior of the studied alloy under high-speed impact along ED and *** correlation coefficient(R)and average absolute relative error(AARE)are 98.63%and 0.0199 for ED,and 96.88%and 0.0202 for TD,respectively.

关键词： High-speed impact Magnesium alloy Twinning behavior Constitutive model Anisotropy

Effect of Regulatory Network of Exosomes and microRNAs on Neurodegenerative Diseases

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Chinese Medical Journal 2018年第18期131卷 2216-2225页

作者： Dong Li You-ping Li Yun-Xiang Li xiao-Hua Zhu xiao-Gang Du Min Zhou Wen-Bin Li Hong-Yan Deng Department of Environmental Engineering College of Environmental Science and Engineering China West Normal University Nanchong Sichuan 637009 China Department of Engineering and Applied Biology College of Life Science Sichuan Agricultural University Ya'an Sichuan 625014 China Department of Environmental Geology College of Environmental and Civil Engineering Chengdu University of Technology Chengdu Sichuan 610059 China

Objective： A comprehensive review of the network regulation of exosomes and microRNAs （miRNAs） in neurodegenerative diseases was done, centering on the mechanism of the formation of exosomes and miRNAs and the sorting mechanism of exosomal miRNAs, with the aim to provide a theoretical basis in the search of biomarkers and the treatment of neurodegenerative diseases. Data Sources： The comprehensive search used online literature databases including NCBI PubMed, Web of Science, Google Scholar, and Baidu Scholar. Study Selection- The study selection was based on the following keywords： exosomes, miRNAs, central nervous system （CNS）, and neurodegenerative diseases. The time limit for literature retrieval was from the year 2000 to 2018, with language restriction in English. Relevant articles were carefully reviewed, with no exclusions applied to study design and publication type. Results： Exosomes are the smallest nanoscale membranous microvesicles secreted by cells and contain important miRNAs, among other rich contents. In the CNS, exosomes can transport amyloid β-protein, α-synuclein, Huntington-associated protein 1, and superoxide dismutase I to other cells. These events relieve the abnormal accumulation of proteins and aggravating neurological diseases. In some neurodegenerative diseases including Alzheimer＇s disease, Parkinson＇s disease, Huntington＇s disease, and amyotrophic lateral sclerosis, miRNAs are pathologically altered as an inexorable course, suggesting that miRNAs may contribute neurodegeneration. Exosomes and miRNAs form a network to regulate the homeostasis of the CNS, both synergistically and individually. Conclusion： The network of exosomes and miRNAs that regulates CNS homeostasis is a promising biomarker for the diagnosis and treatment of neurodegenerative diseases.

关键词： Central Nervous System Exosomes microRNAs Neurodegenerative Diseases

Lactonization of 5-Phenylfuran-4-arylcarbinol-3-carboxylic Acids under the Catalysis of Boron Trifluoridc Etherate

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Chinese Chemical Letters 1999年第2期10卷 103-104页

作者： xiao ping NIE Xiu Lin YE (Department of Chemistry, Peking University． Beijing， 100871) Department of Chemistry Peking University Beijing 100871 China

?-Phenyl－4－aroylfuran－3－carboxylic acids were reduced in aqueous alkaline solutions ofNaBH4 to afford hydroxy acids in excellent yields． Under the catalysis of boron trifluoride etherate，the hydroxy acids were c... 详细信息

关键词： Lactonization boron trifluoride etherate hydroxy acid

Tetrazole-1-acetic acid as a ligand for copper-catalyzed N-arylation of imidazoles with aryl iodides under mild conditions

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Chinese Chemical Letters 2013年第10期24卷 893-896页

作者： Feng-Tian Wu ping Liu xiao-Wei Ma Jian-Wei Xie Bin Dai School of Chemistry and Chemical Engineering/the Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi University

Tetrazole-l-acetic acid was found to serve as a superior ligand for Cul-catalyzed N-arylation of imidazoles with aryl iodides under a low catalyst loading （5 mol% of Cul）. A variety of aryl iodides could he aminated... 详细信息

关键词： Tetrazole-l-acetic acid N-Arylation Imidazoles Copper Aryl iodides