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内毒素血症与肝窦内氧化物和抗氧化物平衡 被引量:1
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作者 王振岳 《国外医学(创伤与外科基本问题分册)》 1999年第4期213-216,共4页
内毒素血症引起肝窦内氧化应激的效果既取决于吞噬细胞或肝细胞内产生的活性氧的多少,也取决于肝窦内皮细胞对活性氧的去毒能力。磷酸己糖旁路既可支持氧化物生成途径,也可支持抗氧化物生成途径。内皮细胞葡萄糖摄取的增加和磷酸己糖旁... 内毒素血症引起肝窦内氧化应激的效果既取决于吞噬细胞或肝细胞内产生的活性氧的多少,也取决于肝窦内皮细胞对活性氧的去毒能力。磷酸己糖旁路既可支持氧化物生成途径,也可支持抗氧化物生成途径。内皮细胞葡萄糖摄取的增加和磷酸己糖旁路的加强可上调还原型辅酶Ⅱ依赖的活性氧去毒途径。 展开更多
关键词 内毒素血症 磷酸己糖旁路 氧化物平衡 肝窦
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亚氯酸盐制备二氧化氯的pε-pH图分析 被引量:1
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作者 田朝晖 裴元生 《兰州铁道学院学报》 2002年第1期97-100,共4页
在三元氯氧化物平衡基础上 ,建立了包括HClO2 、ClO-2 、HOCl、OCl-、Cl2 (aq)和Cl的多元氯氧化物pε- pH图 ,探讨了标准状态下电子活度 (pε)和pH对ClO2 制备的影响 .采用Cl2 (aq)和ClO-2 制备ClO2 时 ,理想的pH条件是 1.35~ 1.94 ,p... 在三元氯氧化物平衡基础上 ,建立了包括HClO2 、ClO-2 、HOCl、OCl-、Cl2 (aq)和Cl的多元氯氧化物pε- pH图 ,探讨了标准状态下电子活度 (pε)和pH对ClO2 制备的影响 .采用Cl2 (aq)和ClO-2 制备ClO2 时 ,理想的pH条件是 1.35~ 1.94 ,pε大于 2 3.31;当采用Cl2 (g)与ClO-2 溶液直接接触制备ClO2 时 ,由于Cl2 歧化为HOCl的反应时间缩短 ,可以抑制副产物的形成 . 展开更多
关键词 氧化 亚氯酸盐 反应自由能 pε-pH图 三元氯氧化物平衡
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基于最小Gibbs自由能原理的铁氧化物气固还原热力学研究 被引量:5
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作者 李彬 郭汉杰 +1 位作者 郭靖 孙贯永 《工程科学学报》 EI CSCD 北大核心 2017年第11期1653-1660,共8页
基于最小Gibbs自由能原理建立了铁氧化物气固还原反应的热力学模型,由模型计算结果作出铁氧化物气固还原反应平衡图,与文献中实验数据吻合良好.与常用冶金学教材和热力学数据库中给出的参考数据进行了对比,不同来源的热力学数据差异较大... 基于最小Gibbs自由能原理建立了铁氧化物气固还原反应的热力学模型,由模型计算结果作出铁氧化物气固还原反应平衡图,与文献中实验数据吻合良好.与常用冶金学教材和热力学数据库中给出的参考数据进行了对比,不同来源的热力学数据差异较大.探究了铁氧化物逐级还原的热力学平衡情况.计算了CO和H2混合气体还原铁氧化物的热力学平衡,推导了平衡时气体总利用率η总的计算公式,作出了CO和H2混合气体还原铁氧化物的三维平衡图,并与文献中实验数据对比,验证了结果的正确性. 展开更多
关键词 氧化物 气固还原 最小Gibbs自由能原理 热力学平衡 氧化物还原平衡
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First-principles thermodynamics of metal-oxide surfaces andinterfaces:A case study review 被引量:4
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作者 江勇 许灿辉 蓝国强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期180-192,共13页
An important step for achieving the knowledge-based design freedom on nano-and interfacial materials is attained by elucidating the related surface and interface thermodynamics from the first principles so as to allow... An important step for achieving the knowledge-based design freedom on nano-and interfacial materials is attained by elucidating the related surface and interface thermodynamics from the first principles so as to allow engineering the microstructures for desired properties through smartly designing fabrication processing parameters.This is demonstrated for SnO2 nano-particle surfaces and also a technologically important Ag-SnO2 interface fabricated by in-situ internal oxidation.Based on defect thermodynamics,we first modeled and calculated the equilibrium surface and interface structures,and as well corresponding properties,as a function of the ambient temperature and oxygen partial pressure.A series of first principles energetics calculations were then performed to construct the equilibrium surface and interface phase diagrams,to describe the environment dependence of the microstructures and properties of the surfaces and interfaces during fabrication and service conditions.The use and potential application of these phase diagrams as a process design tool were suggested and discussed. 展开更多
关键词 metal oxide surface phase diagram interface phase diagram equilibrium crystal shape FIRST-PRINCIPLES THERMODYNAMICS
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Fat poetry:a kingdom for PPARγ 被引量:10
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作者 Silvia I Anghel Walter Wahli 《Cell Research》 SCIE CAS CSCD 2007年第6期486-511,共26页
Adipose tissue is not an inert cell mass contributing only to the storage of fat, but a sophisticated ensemble of cellular components with highly specialized and complex functions. In addition to managing the most imp... Adipose tissue is not an inert cell mass contributing only to the storage of fat, but a sophisticated ensemble of cellular components with highly specialized and complex functions. In addition to managing the most important energy reserve of the body, it secretes a multitude of soluble proteins called adipokines, which have beneficial or, alternatively, deleterious effects on the homeostasis of the whole body. The expression of these adipokines is an integrated response to various signals received from many organs, which depends heavily on the integrity and physiological status of the adipose tissue. One of the main regulators of gene expression in fat is the transcription factor peroxisome proliferatoractivated receptor γ (PPARγ), which is a fatty acid- and eicosanoid-dependent nuclear receptor that plays key roles in the development and maintenance of the adipose tissue. Furthermore, synthetic PPAR7 agonists are therapeutic agents used in the treatment of type 2 diabetes. This review discusses recent knowledge on the link between fat physiology and metabolic diseases, and the roles of PPARγ in this interplay via the regulation of lipid and glucose metabolism. Finally, we assess the putative benefits of targeting this nuclear receptor with still-to-be-identified highly selective PPARγ modulators. 展开更多
关键词 adipose tissue energy homeostasis OBESITY peroxisome proliferator-activated receptor
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Electromotive Force for Solid Oxide Fuel Cells Using Biomass Produced Gas as Fuel 被引量:2
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作者 Wei Zhu Yan-hong Yin +2 位作者 Cen Gao Chang-rong Xia Guang-yao Meng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第4期325-328,共4页
The electromotive force (e.m.f.) of solid oxide fuel cells using biomass produced gas (BPG) as the fuels is calculated at 700-1,200 K using an in-house computer program, based on thermodynamic equilibrium analysis... The electromotive force (e.m.f.) of solid oxide fuel cells using biomass produced gas (BPG) as the fuels is calculated at 700-1,200 K using an in-house computer program, based on thermodynamic equilibrium analysis. Tour program also predicts the concentration of oxygen in the fuel chamber as well as the concentration of equilibrium species such as H2, CO, CO2 and CH4. Compared with using hydrogen as a fuel, the e.m.f. for cells using BPG as the fuels is relative low and strongly influenced by carbon deposition. To remove carbon deposition, the optimum amount of H2O to add is determined at various operating temperatures. Further the e.m.f, for cells based on yttria stabilized zirconia and doped ceria as electrolytes are compared. The study reveals that when using BPG as fuel, the depression of e.m.f, for a SOFC using doped ceria as electrolyte is relatively small when compared with that using Yttria stabilized zirconia. 展开更多
关键词 Biomass produced gas Electromotive force Solid oxide fuel cells Thermodynamic equilibrium
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Effect of interlayer anions on chromium removal using Mg–Al layered double hydroxides:Kinetic,equilibrium and thermodynamic studies 被引量:3
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作者 Mohamed Khitous Zineb Salem Djamila Halliche 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第4期433-445,共13页
The influence of interlayer anions such as NO3-, 5042- and Cl- on Mg-AI hydrotalcites for Cr(Vl) removal from aqueous solution was studied. The structure of the prepared LDHs was characterized by XRD, SEM, FTIR, TGA... The influence of interlayer anions such as NO3-, 5042- and Cl- on Mg-AI hydrotalcites for Cr(Vl) removal from aqueous solution was studied. The structure of the prepared LDHs was characterized by XRD, SEM, FTIR, TGA, BET surface area and pHzpc. The sorbent ability and sorption mechanisms were also investigated. The LDHs exhibit high removal for Cr(VI), and the sorbed amount depends on the nature of interlayer anion, which decreased in the following order: NO3- 〉 Cl 〉 SO42-, Nitrate-containing LDH reached a Cr(VI) sorption equilibrium within only 30 min. The effects of operating conditions, including initial concentration, solution pH, agitation time and sorbent amount have been studied in batch mode. The optimum conditions were observed at an initial concen- tration of 100 mg. L- 1, pH = 6, agitation time of 60 min and a sorbent dose of 2 g.L- 1. The equilibrium data were fitted to the Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The Langmuir model was found to sufficiently describe the sorption process, offering a maximum sorption capacity of 71.91 mg-g 1. The sorp- tion kinetic follows pseudo-second-order reaction with high accuracy. Thermodynamic parameters suggested that the sorption process is spontaneous and endothermic in nature. 展开更多
关键词 HydrotalciteCr(VI)SorptionLayered double hydroxideKinetic
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Prediction of Phase Behavior for Styrene/CO2/Polystyrene Mixtures 被引量:1
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作者 吴家龙 潘勤敏 G.L.Rempel 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第6期706-710,共5页
A lattice fluid model, Sanchez-Lacombe equation, is used to predict the phase behavior for a styrene/CO2/polystyrene ternary sys-tem. The binary parameters involved in the equation were optimized using experimental da... A lattice fluid model, Sanchez-Lacombe equation, is used to predict the phase behavior for a styrene/CO2/polystyrene ternary sys-tem. The binary parameters involved in the equation were optimized using experimental data. Phase diagrams and the distribution coefficients of styrene between polymer phase and fluid phase are obtained over a wide range of pressure, temperature and composition. The analysis of ter-nary phase diagrams indicates that this system at relatively high pressure or low temperature may display two-phase equilibrium, and at low pressures or high temperatures three-phase equilibrium may appear. The distribution coefficients of styrene between the fluid phase and the polymer phase increase asymptotically to unity when the concentration of styrene increases. The results provide thermodynamic knowledge for further exploitation of supercritical carbon dioxide assisted devolatilization and impregnation. 展开更多
关键词 ternary phase diagram distribution coefficient POLYSTYRENE supercritical fluid
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The Role of the Dipole Interaction of Molecules with Charged Particles in the Polar Stratosphere
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作者 Yury Belikov Sergey Nikolayshvili 《Journal of Earth Science and Engineering》 2016年第3期115-149,共35页
Our analysis of published results of experiments in the Polar Regions substantiates and further develops our new approach to the photochemical processes in the polar stratosphere involving the charged particles. The d... Our analysis of published results of experiments in the Polar Regions substantiates and further develops our new approach to the photochemical processes in the polar stratosphere involving the charged particles. The dipole interaction of molecules with charged particles, primarily with ions, leads to the adhesion and disintegration of a number of molecules including ozone. Molecules acquire additional energy on the surface of the charged particles, enabling reactions that are not possible in space. Galactic cosmic rays are the main source of ions in the polar stratosphere, their equilibrium concentration at altitudes of 15 to 25 km can reach up ~ (1-5) ~ 103 ions/cm3. Estimations show that if the ozone destruction in the regime of"collision" with ions then the lifetime of ozone will vary from 10 days to 2 months. We suppose that alongside with the chlorine mechanism of ozone destruction there is a mechanism of ozone decay on a charged particle which can act also at those latitudes and altitudes where chlorine oxide CIO is absent, as well as in the night conditions. Here, we demonstrated the close connection of photochemical processes with the dynamic, electrical and condensational phenomena in the stratosphere, in particular, with the accumulation of unipolar charged particles on the upper and lower boundaries of the polar stratospheric clouds and aerosol layers as a result of the activity of the global electric circuit. 展开更多
关键词 Polar stratosphere OZONE charged particles dipole interaction global electric circuit photochemistry.
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慢性阻塞性肺疾病易感基因的研究进展 被引量:6
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作者 安海燕 凌敏 《临床医学》 CAS 2012年第8期105-107,共3页
慢性阻塞性肺疾病(COPD)是以不完全可逆的气流受限为特征的疾病,与肺部对香烟、烟雾等有害气体或有害颗粒的异常炎性反应有关.吸烟是COPD发病机制中的最重要因素.然而,所有大量吸烟者中只有10%~20%发展成COPD[1],约1/4-1/5的COPD患者... 慢性阻塞性肺疾病(COPD)是以不完全可逆的气流受限为特征的疾病,与肺部对香烟、烟雾等有害气体或有害颗粒的异常炎性反应有关.吸烟是COPD发病机制中的最重要因素.然而,所有大量吸烟者中只有10%~20%发展成COPD[1],约1/4-1/5的COPD患者从不吸烟.这些研究证实除吸烟之外还有其他因素对于COPD的发展起重要作用.COPD具有家族聚集性,在父母和孩子之间或同胞之间比配偶间有更强的联系[2].他们的遗传方式并不符合孟德尔的遗传规律,对于遗传易感在COPD的发展过程中起作用提供了证据.本综述将讨论在COPD发展过程中的易感基因的研究进展.在基因多态性的研究中有两个平衡假说引起普遍的关注,这两个平衡就是蛋白酶/抗蛋白酶平衡和氧化物/抗氧化物平衡,本研究主要围绕这两方面的研究进行综述. 展开更多
关键词 慢性阻塞性肺疾病 易感基因 COPD患者 氧化物平衡 异常炎性反应 抗蛋白酶 家族聚集性 基因多态性
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Meta-analysis reveals that reproductive strategies are associated with sexual differences in oxidative balance across vertebrates 被引量:2
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作者 David COSTANTINI 《Current Zoology》 SCIE CAS CSCD 2018年第1期1-11,共11页
Oxidative stress is a key physiological mechanism underlying life-history tradeoffs. Here, I use meta-analytic techniques to test whether sexual differences in oxidative balance are common in vertebrates and to identi... Oxidative stress is a key physiological mechanism underlying life-history tradeoffs. Here, I use meta-analytic techniques to test whether sexual differences in oxidative balance are common in vertebrates and to identify which factors are associated with such differences. The dataset included 732 effect size estimates from 100 articles (82 species). Larger unsigned effect size (meaning larger sexual differences in a given marker) occurred in: reptiles and fish; those species that do not pro- vide parental care; and oviparous species. Estimates of signed effect size (positive values meaning higher oxidative stress in males) indicated that females were less resistant to oxidative stress than males in: reptiles while males and females were similar in fish, birds, and mammals; those species that do not provide parental care; and oviparous species. There was no evidence for a significant sexual differentiation in oxidative balance in fish, birds, and mammals. Effect size was not associ- ated with: the number of offspring; whether the experimental animals were reproducing or not; biomarker (oxidative damage, non-enzymatic, or enzymatic antioxidant), the species body mass; the strain (wild vs. domestic); or the study environment (wild vs. captivity). Oxidative stress tended to be higher in females than males across most of the tissues analyzed. Levels of residual heterogeneity were high in all models tested. The findings of this meta-analysis indicate that diversification of reproductive strategies might be associated with sexual differences in oxidative balance. This explorative meta-analysis offers a starting platform for future research to investigate the rela-tionship between sex and oxidative balance further. 展开更多
关键词 ANTIOXIDANTS OVIPARITY oxidative damage parental care vertebrates viviparity.
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