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理想气体直线过程的再讨论
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作者 伍文宜 《甘肃高师学报》 2002年第2期35-36,共2页
用直线的斜率讨论理想气体直线过程中温度的变化及吸放热的情况 ,并将其结果应用于P -V图上理想气体任意过程吸放热的讨论 ,避免了理想气体任意过程吸放热计算中错误的出现 .
关键词 理想气候 直线过程 斜率 微元过程 温度变化 P-V图 吸热过程 放热过程
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理想气体任意准静态过程吸放热研究 被引量:1
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作者 王子红 《雁北师范学院学报》 2006年第2期84-86,共3页
从微元过程和宏观过程的角度,对理想气体任意准静态过程的吸、放热进行了研究.
关键词 理想气体 准静态过程 微元过程及应放热分界态
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火箭运动动力学方程 被引量:2
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作者 李燕山 《中州大学学报》 1999年第3期85-86,共2页
火箭类物体,在运动过程中主体质量不断变化,用动力学基本方程f=dma/dt分析其运动的理论较多,本文阐明了动力学基本方程f=am同样适合火箭类变质量物体的运动。
关键词 运动动力学 质点系 火箭 反推力 动量定理 牛顿运动方程 运动对象 合外力 不变质量 微元过程
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Blood micronutrient, oxidative stress, and viral load in patients with chronic hepatitis C 被引量:6
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作者 Wang-Sheng Ko Chih-Hung Guo +5 位作者 Maw-Sheng Yeh Li-Yun Lin Guoo-Shyng W. Hsu Pei-Chung Chen Mei-Ching Luo Chia-Yeh Lin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第30期4697-4702,共6页
AIM: To assess the extent of micronutrient and oxidative stress in blood and to examine their linkages with viral loads in chronic hepatitis C patients.METHODS: Hepatitis C virus (HCV)-RNA levels were quantified in th... AIM: To assess the extent of micronutrient and oxidative stress in blood and to examine their linkages with viral loads in chronic hepatitis C patients.METHODS: Hepatitis C virus (HCV)-RNA levels were quantified in the serum from 37 previously untreated patients with chronic hepatitis C. The plasma and erythrocyte micronutrients (zinc, selenium, copper, and iron) were estimated, and malondialdehyde (MDA)contents were determined as a marker to detect oxidative stress. Antioxidant enzymes, superoxide dismutase (SOD),glutathione peroxidase (GPX) and glutathione reductase (GR) activities in blood were also measured. The control group contained 31 healthy volunteers.RESULTS: The contents of zinc (Zn), and selenium (Se)in plasma and erythrocytes were significantly lower in hepatitis C patients than in the controls. On the contrary,copper (Cu) levels were significantly higher. Furthermore,plasma and erythrocyte MDA levels, and the SOD and GR activities in erythrocytes significantly increased in hepatitis C patients compared to the controls. However, the plasma GPX activity in patients was markedly lower. Plasma Se (r= -0.730, P<0.05), Cu (r = 0.635), and GPX (r = -0.675)demonstrated correlations with HCV-RNA loads. Significant correlation coefficients were also observed between HCV-RNA levels and erythrocyte Zn (r = -0.403), Se (r = -0.544), Cu (r = 0.701) and MDA (r = 0.629) and GR (r = 0.441).CONCLUSION: The levels of Zn, Se, Cu, and oxidative stress (MDA), as well as related anti-oxidative enzymes (GR and GPX) in blood have important impact on the viral factors in chronic hepatitis C. The distribution of these parameters might be significant biomarkers for HCV. 展开更多
关键词 MICRONUTRIENT Oxidative stress Viral load Plasma and erythrocytes Hepatitis C
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The transformation and concentration of environmental hazardous trace elements during coal combustion 被引量:1
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作者 YAO Duo-xi ZHI Xia-chen 《Journal of Coal Science & Engineering(China)》 2010年第1期74-77,共4页
Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transf... Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transformations and concentration of 18 traceelements during different coal combustion were discussed.The results show that there aresome content distribution of 18 hazardous trace elements in every burnt product, but thelaw of concentration and dispersion of every trace element during different coal combustionis very different.Experiment results indicate that the transformation and concentrationof trace elements during coal combustion are related to the element contents and occur-rencesof trace elements in raw coal, but are also affected by some man-made factorssuch as the combustion method of boiler, combustion temperature and atmosphere, thetype of precipitators and so on. 展开更多
关键词 environmental hazardous trace elements transformation and concentration coal combustion
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Inhibiting Human Copper Transfer and Tumor Growth
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《Bulletin of the Chinese Academy of Sciences》 2015年第4期250-250,共1页
Copper is a trace element that is required by almost all forms of life.Acting as cofactors for various key metabolism enzymes,copper takes part in many vital biological processes.Previous studies have found the concen... Copper is a trace element that is required by almost all forms of life.Acting as cofactors for various key metabolism enzymes,copper takes part in many vital biological processes.Previous studies have found the concentration of copper is significantly higher in tumor cells than in normal cells.In addition,copper can promote angiogenesis by activating VEGF and FGF signaling. 展开更多
关键词 metabolism activating angiogenesis vital signaling enzymes biochemical regulate targeting Nature
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Effects of microcracks on the poroelastic behaviors of a single osteon 被引量:1
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作者 WU XiaoGang WANG YanQin +3 位作者 WU XiaoHong CEN HaiPeng GUO Yuan CHEN WeiYi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第11期2161-2167,共7页
It has been suggested that microcracks do play a key role in the triggering of the bone remodeling process.In order to evaluate the influence of microcracks on the poroelastic behaviors of an osteon,a finite element m... It has been suggested that microcracks do play a key role in the triggering of the bone remodeling process.In order to evaluate the influence of microcracks on the poroelastic behaviors of an osteon,a finite element model is established and investigated by using the Comsol Multiphysics software.The findings show that the presence of a microcrack in the osteon wall strongly modifies(enlarges)its local fluid pressure and velocity.Especially,the pressure and velocity amplitudes produced in the microcracked region are larger than those of the non-cracked region.Thus,this study can also be used for proposing a likely mechanism that bone can sense the changes of surrounding mechanical environments. 展开更多
关键词 cracked permeability environments remodeling likely Figure surrounding skeleton porosity triggering
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Weathering reflected by the chemical composition of alluvial soils from the Zeya and Selemdzha river valleys 被引量:2
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作者 O.A.SOROKINA M.N.GYSEV 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第5期604-613,共10页
The paper examines the chemical composition of alluvial soils from the Zeya and Selemdzha River valleys, one of the branch rivers in the Amur River basin. It has been established that the compositions of these soils a... The paper examines the chemical composition of alluvial soils from the Zeya and Selemdzha River valleys, one of the branch rivers in the Amur River basin. It has been established that the compositions of these soils are characterized by a relative shortage of practically all analyzed macro-and microelements as compared with UCC(upper continental crust) and PAAS(postArhean Australian average shale) compositions. The chemical composition of alluvial soils approximates that of the soils in NE China and Korea due to similar climatic and geographic conditions. On the basis of relationships between major and trace elements and peculiarities of trace elements concentration it is shown that the alluvial soils in the middle reaches of the Zeya River were formed by the sources largely transformed by chemical weathering processes. By comparison, the soils in the Selemdzha River and lower reaches of the Zeya River(below the Selemdzha River mouth) are dominated by material to a large degree reworked by the physical processes rather than chemical ones. This inference conforms with specific geological settings of the water-collector. 展开更多
关键词 Alluvial soils Weathering indices Amur Zeya
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