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PM_(2.5) obtained from urban areas in Beijing induces apoptosis by activating nuclear factor-kappa B

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Military Medical Research 2017年第4期4卷 200-209页

作者： Hui Peng Xiao-Hong Zhao Ting-Ting Bi Xiao-Yan Yuan jia-bin guo Shuang-Qing Peng Evaluation and Research Center for Toxicology Institute of Disease Control and Prevention Academy of Military Medical Sciences Beijing Key Laboratory of Bioactive Substances and Functional Foods Beijing Union University

Background: Particulate matter(PM), which has adverse effects on citizen health, is a major air pollutant in Beijing city. PM_(2.5) is an indicator of PM in urban areas and can cause serious damage to human health. Many epidemiological studies have shown that nuclear factor-kappa B(NF-κB) is involved in PM_(2.5)-induced cell injury, but the exact mechanisms are not well ***: The cytotoxic effects of PM_(2.5) at 25–1600μg/ml for 24 h were determined by MTT assay in Chinese hamster ovary cells(CHO) cells. Flow cytometry was used to determine the apoptosis rate induced by PM_(2.5). The destabilized enhanced green fluorescent protein(d2 EGFP) green fluorescent protein reporter system was used to determine the NF-κB activity induced by PM_(2.5). The expression of pro-apoptotic Bcl-2-associated death promoter(BAD) proteins induced by PM_(2.5) was determined by Western blotting to explore the relationship between PM_(2.5) and the NF-κB signaling pathway and to determine the toxicological mechanisms of PM_(2.5).Results: PM_(2.5) collected in Beijing urban districts induces cytotoxic effects in CHO cells according to MTT assay with 72.28% cell viability rates even at 200μg/ml PM_(2.5) and flow cytometry assays with 26.97% apoptosis rates at 200μg/ml PM_(2.5). PM_(2.5) increases the activation levels of NF-κB, which have maintained for 24 h. 200μg/ml PM_(2.5) cause activation of NF-κB after exposure for 4 h, the activation peak appears after 13.5 h with a peak value of 25.41%. The average percentage of NF-κB activation in whole 24 h is up to 12.90% by 200μg/ml PM_(2.5). In addition, PM_(2.5) decreases the expression level of the pro-apoptotic protein BAD in a concentration-dependent ***: PM_(2.5) induces NF-κB activation, which persists for 24 h. The expression of pro-apoptotic protein BAD decreased with increased concentrations of PM_(2.5). These findings suggest that PM_(2.5) plays a major role in apoptosis by activating the NF-κB signaling path

关键词： Particulate matter NF-κB pathway Apoptosis BAD protein

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“三大考评体系”的实践与思考

消防科学与技术 2013年第8期32卷 915-918页

作者：贾国斌贵州省消防总队贵州贵阳550007

结合消防工作实际,对消防工作绩效考评制度设计、考评方式方法和考评结果运用等内容进行了研究,探讨并建立了以消防执法质量考评、宣传教育考评和公安派出所消防监督工作考评"三位一体"的消防工作绩效考评体系。

关键词：社会消防量化管理绩效考评消防监督

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng Wang Qinyi guo bin Hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

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分子动力学模拟Pb-Au合金的热力学性质

中国有色金属学报 2010年第4期20卷 784-787页

作者：贾国斌刘媛媛杨斌刘大春昆明理工大学真空冶金国家工程实验室昆明650093

采用分子动力学方法模拟Pb8Au2和Pb9Au1两种合金体系的热力学性质。计算不同温度下合金体系的生成焓、生成自由能和过剩自由能,同时计算合金的结合能,从宏观和微观角度分析二元合金原子间相互作用,得到的计算结果与实验数据吻合得很好。

关键词： Pb-Au合金 Pb8Au2合金 Pb9Au1合金分子动力学生成焓生成自由能过剩自由能结合能

Observation of the Superheavy Nuclide ^(271)Ds

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Chinese Physics Letters 2012年第1期29卷 68-70页

作者： ZHANG Zhi-Yuan GAN Zai-guo MA Long HUANG Ming-Hui HUANG Tian-Heng WU Xiao-Lei jia guo-bin LI Guang-Shun YU Lin REN Zhong-Zhou ZHOU Shan-Gui ZHANG Yu-Hu ZHOU Xiao-Hong XU Hu-Shan ZHANG Huan-Qiao XIAO guo-Qing ZHAN Wen-Long Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 Department of Physics Nanjing UniversityNanjing 210093 State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190 China Institute of Atomic Energy Beijing 102413 Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion AcceleratorLanzhou 730000 Graduate University of Chinese Academy of Sciences Beijing 100049

With the recent commissioning of a gas-filled recoil separator at Institute of Modern Physics (IMP) in Lanzhou,the decay properties of 271Ds (Z =110) were studied via the 20sPb(64Ni,n) reaction at a beam energy of 313.3 *** on the separator coupled with a position sensitive silicon strip detector,we carried out the energy-position-time correlation measurements for the implanted nucleus and its subsequent decay α'*** α-decay chain for 271Ds was *** α energy and decay time of the 27iDs nucleus were measured to be 10.644 MeV and 96.8ms,which are consistent with the values reported in the literature.

关键词： decay filled subsequent

维普期刊数据库评论

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大跨连体钢桁架整体提升施工技术

建筑技术 2017年第2期48卷 126-129页

作者：刘家彬郭正兴夏虎东南大学土木工程学院南京210096

南京六合金融大厦连体钢桁架跨度32 m,总重约300 t,为缩短工期、降低成本,工程按"地面拼装、整体提升"的思路,采用液压整体提升施工技术安装连体钢桁架。通过将钢桁架整体提升部分长度,对桁架端部进行整体加固处理;分析在提升点间存在... 详细信息

南京六合金融大厦连体钢桁架跨度32 m,总重约300 t,为缩短工期、降低成本,工程按"地面拼装、整体提升"的思路,采用液压整体提升施工技术安装连体钢桁架。通过将钢桁架整体提升部分长度,对桁架端部进行整体加固处理;分析在提升点间存在不同步的情况下,桁架应力与位移的变化情况;总结5个同步性控制措施的方法,分别解决了在正式提升时桁架总重过大而引起的界面承载力过大,提升过程中桁架挠度过大与人工控制时提升点间不同步的难题。实践表明,整体提升施工技术安全、经济、高效,是同类结构施工的理想方法。

关键词：整体提升连体钢桁架同步控制

2014年浑善达克沙地黄柳生长季水分来源同位素示踪研究

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干旱区研究 2017年第2期34卷 350-355页

作者：菅晶贾德彬郭少峰钱龙娇内蒙古农业大学水利与土木建筑工程学院内蒙古呼和浩特010018

黄柳是我国内蒙古东部和辽宁西部沙丘上广泛分布的多年生灌木,是极佳的固沙树种。通过利用氢同位素示踪方法,测定了2014年浑善达克沙地黄柳生长季茎干水与潜在水源(降水、土壤水、地下水)氢同位素比率δD值,并利用多源线性混合模型Iso S... 详细信息

黄柳是我国内蒙古东部和辽宁西部沙丘上广泛分布的多年生灌木,是极佳的固沙树种。通过利用氢同位素示踪方法,测定了2014年浑善达克沙地黄柳生长季茎干水与潜在水源(降水、土壤水、地下水)氢同位素比率δD值,并利用多源线性混合模型Iso Source,计算了黄柳对各潜在水源的利用比例。结果表明:在5月黄柳80%以上利用120~160 cm土壤水和地下水;6月主要吸收0~40 cm土壤水;7月主要吸收120~160 cm土壤水;8月以地下水为主要水源,利用率为82%。这表明生长在不同季节的黄柳对于各潜在水源的利用有特定的适应结果,同时也说明荒漠灌木可以通过自身的调节朝着最优的方向发展,实现最大限度的水分利用。

关键词：黄柳(Salix gordejevii) 稳定氢同位素 Iso Source模型水分来源

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang jia guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

生命安全指南——保护生命和财产安全的七步曲

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消防技术与产品信息 2007年第1期20卷 62-64页

作者：雷蕾贾国斌

车站夜总会位于美国罗德岛州西沃瑞克镇,2003年发生的一场火灾夺去了夜总会内99人的生命并有150余人受伤.

关键词：生命安全财产安全建筑火灾保护指南手提式灭火器水喷淋系统夜总会