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Fe Kα line profile in AGNs: average shape and redshift dependence

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Research in Astronomy and Astrophysics 2010年第9期10卷 905-914页

作者： Wei-ming Mao chen Hu Jian-min Wang Gang Zhao Shu Zhang Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We collect a sample of 381 （271 type Ⅰ） active galactic nuclei （AGNs） with XMM-Newton observations for an analysis of the dependence of Fe Kα profiles on redshifts to test the potential cosmological evolution of spins of supermassive black holes （SMBHs）. The sample spans a redshift range of z = 0.0008 - 4.76, which allows us to rebin the sample into 7 redshift groups. Phenomenological analysis of the Fe profile suggested that the line width （δ） of the narrow or broad Fe line does not show significant changes in redshift range z 〈 0.3. Using a physical model, we significantly detect a narrow Fe Kα line at 6.4 keV with an average equivalent width （EW） = 160 eV except for the two largest redshift bins. The EW of the Fe line does not show significant changes. We also find a relativistic broad line in three redshift bins （z 〈 0.116, 0.056 〈 z 〈 0.12 and 0.12 〈 z 〈 0.3）with an average EW = 522eV.

关键词： galaxies active -- X-rays general -- methods data analysis

Influence of asymmetric blockage of the drainage system of a deep-buried tunnel on water gushing

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Journal of Mountain Science 2022年第7期19卷 2075-2085页

作者： FU He-lin AN Peng-tao WU Yi-min LI Jie chen Long School of Civil Engineering Central South UniversityChangsha410075China National Engineering Laboratory for Construction Technology of High Speed Railway Central South UniversityChangsha410075China

Asymmetric blockage of drainage systems occasionally occurs,which seriously threatens the safety of tunnel *** on theoretical analysis,a calculation expression of tunnel water inflow involving clogging parameters was *** of the analytical solution was analysed with the Taylor equation and series expansion theorem,and a tunnel under construction was considered to conduct field tests to verify the rationality of the established model and correctness of the derived *** have demonstrated that with increasing drainage system blockage degree,the amount of water inflow in the nonblocked area slowly increases,and the total amount of water in the tunnel gradually *** hydrodynamic pressure in the blocked area non-linearly decreased,and the water inrush velocity and hydraulic gradient in the non-blocked area gradually *** the drainage system was not blocked,the result of tunnel water inflow calculated by the formula derived in this paper was 8.3% higher than the measured *** the drainage system was blocked,the theoretical water inflow was 10.5% higher than the measured *** difference between the measured value and the theoretical value is small,which verifies the effectiveness of the calculation formula of water inflow deduced in this paper.

关键词： Drainage system Asymmetric blockage Water inflow Field test

Microstructure and Optical Characterization of Magnetron Sputtered NbN Thin Films

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Chinese Journal of Aeronautics 2007年第2期20卷 140-144页

作者： DU Xin-kang WANG Tian-min WANG Cong chen Bu-liang ZHOU Long School of Science Beijing University of Aeronautics and Astronautics Beijing 100083 China Mechanical Engineering College Shifiazhuang 050003 China Academy of Space Technology Beijing 100029 China

Some fundamental studies on the preparation, structure and optical properties of NbN films were carried out. NbN thin films were deposited by DC reactive magnetron sputtering at different N2 partial pressures and different substrate temperatures ranging from -50℃ to 600℃. X-ray diffraction analysis （XRD） and scanning electron microscopy （SEM） were employed to characterize their phase components, microstructures, grain sizes and surface morphology. Optical properties inclusive of refractive indexes, extinction coefficients and transmittance of the NbN films under different sputtering conditions were measured. With the increase in the N2 partial pressure, 6-NbN phase structure gets forming and the grain size and lattice constant of the cubic NbN increasing. The deposited NbN film has relatively high values of refractive index and extinction coefficient in the wavelength ranging from 240 nm to 830 nm. Substrate temperature exerts notable influences on the microstructure and optical transmittance of the NbN films. The grain sizes of the 6-NbN film remarkably increase with the rise of the substrate temperature, while the transmittance of the films with the same thickness decreases. Ultra-fine granular film with particle size of several nanometers forms when the substrate is cooled to -50℃, and a remarkable augmentation of transmittance could be noticed under so low a temperature.

关键词： reactive magnetron sputtering NbN thin film microstructure optical properties

Elastocaloric effect and mechanical behavior for NiTi shape memory alloys

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Chinese Physics B 2018年第10期27卷 518-524页

作者： min Zhou Yu-Shuang Li chen Zhang Lai-Feng Li Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The NiTi shape memory alloy exhibits excellent superelastic property and elastocaloric effect. The large temperature change（DT） value of 30 K upon loading and-19 K upon unloading are obtained at room temperature, which are higher than those of the other NiTi-based materials and among the highest values reported in the elastocaloric materials. The asymmetry of the measured DT values between the loading and unloading process is ascribed to the friction *** large temperature change originates from the large entropy change during the stress-induced martensite transformation（MT） and the reverse MT. A large coefficient-of-performance of the material is obtained to be 11.7 at ε= 1%, which decreases with increasing the applied strain. These results are very attractive in the present solid-state cooling, which potentially could replace the vapor compression refrigeration technologies.

关键词： elastocaloric effect shape memory alloy martensitic transformation entropy change

The Impact of Aqueous Medium on Gas Yields and Kinetic Behaviors of Hydrogen Isotope Fractionation during Organic Matter Thermal Degradation

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1466-1477页

作者： LU Shuangfang WANG min XUE Haitao LI Jijun chen Fangwen XU Qingxia Northeast Petroleum University Heilongjiang Province 163318 China

In order to recognize the impact of aqueous medium on gas yields and the kinetic behaviors of hydrogen isotope fractionation during organic matter thermal degradation, the gold tube apparatus was used to conduct thermal simulation experiments by mixing the nC18 with the water of different properties and proportions. The yields of natural gas components, the relation among hydrogen isotope composition of each component and the experimental temperatures vs. heating rates have been obtained, and the results indicate that under the higher temperature conditions, the hydrous experiment has obvious impact on gas yields, such as when more water is added, higher amounts of hydrocarbon gas and H2 are yielded, and the existence of water obviously prolongs the temperature interval with the existence of heavy hydrocarbon gas. It also shows that the hydrogen isotope of hydrocarbon gas generated by the hydrous experiment is obviously lighter than that generated by the anhydrous experiment, and with the increasing amount of added water, the δD value of hydrocarbon gas gradually decreases. Compared with gas yields, the variation of δD value is more sensitive to aqueous medium in the thermal simulation experiment. However, compared with the amount of the added water, the aqueous medium property has smaller impact on the gas yields, which still shows the inherit effect on hydrogen isotope composition of aqueous medium. Through the model simulation and the isotope fractionation behavior analysis, it is validated that the hydrogen isotope fractionation process can be well described by the chemical kinetic model. The difference of reaction fraction of normal methane and D-containing methane is large, corresponding to the same activation energy. The content of normal methane is obviously higher in the part with lower activation energy, while the content of D-containing methane is higher in the part with higher activation energy. Therefore, it will result in larger hydrogen isotope fracti

关键词： hydrogen isotope fractionation chemical kinetics nC18 gas generation hydrous experiment

Sialic acid accelerates the electrophoretic velocity of injured dorsal root ganglion neurons

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Neural Regeneration Research 2015年第6期10卷 972-975页

作者： chen-xu Li Guo-ying Ma min-fang Guo Ying Liu Institute of Brain Sciences Department of Physiology Medical CollegeShanxi Datong University

Peripheral nerve injury has been shown to result in ectopic spontaneous discharges on soma and injured sites of sensory neurons, thereby inducing neuropathic pain. With the increase of membrane proteins on soma and injured site neurons, the negatively charged sialic acids bind to the external domains of membrane proteins, resulting in an increase of this charge. We therefore speculate that the electrophoretic velocity of injured neurons may be faster than non-injured neurons. The present study established rat models of neuropathic pain via chronic constriction injury. Results of the cell electrophoresis test revealed that the electrophoretic velocity of injured neuronal cells was faster than that of non-injured （control） cells. We then treated cells with divalent cations of Ca2＋ and organic compounds with positive charges, polylysine to counteract the negatively charged sialic acids, or neuraminidase to specifically remove sialic acids from the membrane surface of injured neurons. All three treatments significantly reduced the electrophoretic velocity of injured neuronal cells. These findings suggest that enhanced sialic acids on injured neurons may accelerate the electrophoretic velocity of injured neurons.

关键词： This study was supported by the Natural Science Foundation of shanxi Province in China No. 2012011042-3.

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湖北省高端仪器仪表产业标准化建设现状研究

中国标准化 2024年第21期 104-110,162页

作者：董锦绘丁凡杨剑李婳婧涂桂林闵珊湖北省标准化与质量研究院

本文阐述湖北省高端仪器仪表产业的发展现状,并对我国和国外其他国家标准化现状进行研究和分析,结合湖北省高端仪器仪表产业发展现状和对高端仪器仪表企业的实地调研,对湖北省高端仪器仪表标准化建设提出建议,以推动湖北省高端仪器仪表... 详细信息

本文阐述湖北省高端仪器仪表产业的发展现状,并对我国和国外其他国家标准化现状进行研究和分析,结合湖北省高端仪器仪表产业发展现状和对高端仪器仪表企业的实地调研,对湖北省高端仪器仪表标准化建设提出建议,以推动湖北省高端仪器仪表服务型制造高质量发展。

关键词：高端仪器仪表标准化高质量发展

比较手法肺复张和压力控制法肺复张对腹腔镜手术患者术后肺部并发症的影响

维普期刊数据库博看期刊评论

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国际麻醉学与复苏杂志 2024年第3期45卷 259-264页

作者：郭哲源陈雪梅苏尔古格其其格山承鑫李敏王新辉齐向欣许丹阳赤峰学院附属医院麻醉科赤峰024005 汕头大学医学院附属肿瘤医院麻醉科汕头515031

目的比较手法肺复张与压力控制法肺复张在腹腔镜手术中的治疗效果。方法选择90例妇科择期行腹腔镜手术的患者,采用随机数字表法将患者分为3组(每组30例):空白对照组(A组)、手法肺复张组(B组)、压力控制法肺复张组(C组)。3组患者均采用... 详细信息

目的比较手法肺复张与压力控制法肺复张在腹腔镜手术中的治疗效果。方法选择90例妇科择期行腹腔镜手术的患者,采用随机数字表法将患者分为3组(每组30例):空白对照组(A组)、手法肺复张组(B组)、压力控制法肺复张组(C组)。3组患者均采用容量控制模式机械通气,呼吸机参数设置保持一致并在气管插管后每小时及术毕时进行肺复张操作(A组不进行肺复张、B组进行手法肺复张、C组进行压力控制法肺复张)。监测并记录麻醉诱导前5 min(T_(0))、插管后5 min(T_(1))、肺复张前(T_(2))、肺复张后10 min(T_(3))、术毕(T_(4))、拔管后15 min(T_(5))时的平均动脉压(MAP)、心率、脉搏血氧饱和度(SpO_(2));记录T_(1)~T_(4)时的动态肺顺应性(Cdyn)、气道峰压(Ppeak)、呼气末二氧化碳分压(PETCO_(2));T_(0)、T_(5)时进行肺超声检查并采用改良肺部超声检查评分(LUS)对肺复张效果进行评价;记录术后1 d的临床肺部感染评分(CPIS)及术后7 d内3组患者术后肺部并发症(PPC)发生情况;记录手术时间、麻醉时间、拔管时间。结果3组患者美国麻醉医师协会(ASA)分级、体重指数(BMI)、年龄、手术时间、麻醉时间、拔管时间比较,差异无统计学意义(均P>0.05)。A组T_(3)、T_(4)时MAP、心率、Ppeak、PETCO_(2)高于B组、C组(均P0.05)。结论两种肺复张方法均可以改善患者术后肺不张程度,且一定程度上降低PPC的发生率。同时压力控制法肺复张对患者术中气道改善效果更好,对患者术中的血流动力学影响更小,术后肺不张发生率更低。

关键词：腹腔镜手术肺不张肺复张方法术后肺部并发症

Nitrogen uptake regime regulated by ice melting during austral summer in the Prydz Bay, Antarctica

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Acta Oceanologica Sinica 2019年第8期38卷 1-7页

作者： Run Zhang Qiang Ma min chen minfang Zheng Jianping Cao Yusheng Qiu College of Ocean and Earth Sciences Xiamen University Xiamen 361102 China Key Laboratory of Estuarine Ecological Security and Enviromental Health Xiamen University Tan Kah Kee College Zhangzhou 363105 China

Using a combination of stable isotope(15N) and radionuclide(226Ra) analyses, we examine possible controls on the interactions between melting ice and the uptake of nitrogen in the Prydz Bay during the 2006 austral *** find that specific rates of uptake for nitrate and ammonium correlate positively to their concentrations, thus suggesting a substrate effect. In the study area, we observe that regions along open, oceanic water have high fratios(nitrate uptake/nitrate+ammonium uptake), while areas near the Amery Ice Shelf have significantly low fratios. Further analysis reveals a negative correlation between the f-ratio and the melt water fraction, thus implying that the melting of ice plays an essential role in regulating pelagic N dynamics in the Southern Ocean(SO). Stratification, produced by melting ice, should profoundly affect the efficiency of the SO’s biological pump and consequently affect the concentration of CO2 in the atmosphere. Results presented in this study add information to an already significant base of understanding of the controls on pelagic C and N dynamics in the SO. This provides unique insights for either interpreting past changes in geologic records or for predicting future climate change trends.

关键词： nitrogen uptake regime ice melting Prydz Bay Antarctica