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Chinese Science Bulletin 2001年第4期46卷 314-317页

作者： shaokun Chuai Tianhui Hu Jiang Liu Xun Shen Chinese Acad Sci Inst Biophys Beijing 100101 Peoples R China

The respiratory burst is an important physiological function of the neutrophils in killing the bacteria invading in human body. We used chemiluminescence method to measure the exogenous arachidonic acid-stimulated respiratory burst, and measured the cytosolic free calcium concentration in neutrophils by the fluorescence method. It was found that, on one hand, the arachidonic acid-stimulated respiratory burst was enhanced by elevating the cytosolic free calcium concentration in neutrophils with a potent endomembrane Ca2+-ATPase inhibitor, Thapsgargin; on the other hand, chelating the intracellular or extracellular calcium by EGTA or BAPTA inhibited the respiratory burst. Results showed that calcium plays an important regulatory role in the signaling pathway involved in the exogenous arachidonic acid-stimulated respiratory burst of neutrophils.

关键词： arachidonic acid neutrophils respiratory burst chemi-luminescence intracellular calcium extracellular calcium.

Quantifying both climate and land use/cover changes on runoff variation in Han River basin, China

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Frontiers of Earth Science 2022年第3期16卷 711-733页

作者： Jing TIAN Shenglian GUO Jiabo YIN Zhengke PAN Feng XIONG shaokun HE State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Changjiang Institute of Survey PlanningDesign and ResearchWuhan 430010China Bureau of Hydrology Changjiang Water Resources CommissionWuhan 430010China

Climate change and land use/cover change(LUCC)can both exert great impacts on the generation processes of precipitation and ***,previous studies usually neglected considering the contribution component of future LUCC in evaluating changes in hydrological *** this study,an integrated framework is developed to quantify and partition the impact of climate change and LUCC on future runoff ***,a daily bias correction(DBC)method and the Cellular Automaton-Markov(CA-Markov)model are used to project future climate and LUCC scenarios,and then future runoff is simulated by the calibrated Soil and Water Assessment Tool(SWAT)model with different climate and LUCC ***,the uncertainty of future runoff and the contribution rate of the two driving factors are systematically *** Han River basin in China was selected as a case *** indicate that:1)both climate change and LUCC will contribute to future runoff intensification,the variation of future runoff under combined climate and LUCC is larger than these under climate change or LUCC alone;2)the projected uncertainty of median value of multi-models under RCP4.5(RCP8.5)will reach 18.14%(20.34%),12.18%(14.71%),11.01%(13.95%),and 11.41%(14.34%)at Baihe,Ankang,Danjiangkou,and Huangzhuang stations,respectively;3)the contribution rate of climate change to runoff at Baihe,Ankang,Danjiangkou,and Huangzhuang stations under RCP4.5(RCP8.5)are 91%-98%(84%-94%),while LUCC to runoff under RCP4.5(RCP8.5)only accounts for 2%-9%(6%-16%)in the annual *** study may provide useful adaptive strategies for policymakers on future water resources planning and management.

关键词： climate change LUCC runoff response uncertainty analysis contribution rate

Hierarchical Encapsulation and Rich sp^(2)N Assist Sb_(2)Se_(3)-Based Conversion-Alloying Anode for Long-Life Sodium-and Potassium-Ion Storage

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Energy & Environmental Materials 2023年第6期6卷 372-382页

作者： shaokun Chong Meng Ma Lingling Yuan shuangyan Qiao Shihong Dong Huakun Liu Shixue Dou Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics and Xi'an Institute of Biomedical Materials&EngineeringNorthwestern Polytechnical UniversityXi'an 710072China Institute for Superconducting and Electronic Materials University of WollongongWollongong NSW 2522Australia

Sodium-and potassium-ion batteries have exhibited great application potential in grid-scale energy storage due to the abundant natural resources of Na and ***-alloying anodes with high theoretical capacity and low-operating voltage are ideal option for SIBs and PIBs but suffer the tremendous volume ***,a hierarchically structural design and sp^(2)N-doping assist a conversion-alloying material,Sb_(2)Se_(3),to achieve superior life span more than 1000 *** is confirmed that the Sb_(2)Se_(3)evolves into nano grains that absorb on the sp^(2)N sites and in situ form chemical bonding of C-N-Sb after initial *** results indicate that sp^(2)N has more robust interaction with Sb and stronger adsorption capacities to Na^(+)and K^(+)than that of sp3 N,which contributes to the durable cycling ability and high electrochemical activity,*** ex situ transmission electron microscopy and X-ray photoelectron spectroscopy results suggest that the Sb_(2)Se_(3)electrode experiences conversion-alloying dual mechanisms based on 12-electron transfer per formula unit.

关键词： antimony selenide conversion-alloying anode N-doped carbon potassium-ion batteries sodium-ion batteries

时效处理对低压铸造ZL114A合金力学性能及显微组织的影响

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金属热处理 2024年第1期49卷 179-185页

作者：田少鲲金圆平王萍杨堃刘晓霏郭占郁瑞兴范庆利首都航天机械有限公司北京100076

以低压铸造ZL114A合金为研究对象,通过布氏硬度计、万能试验机、光学显微镜等测试手段,对固溶及时效处理后合金的显微组织及力学性能进行了观察、测试。时效初期,合金的强度快速增加,随着时效时间延长,增长趋势放缓;155℃时效12 h后,合... 详细信息

以低压铸造ZL114A合金为研究对象,通过布氏硬度计、万能试验机、光学显微镜等测试手段,对固溶及时效处理后合金的显微组织及力学性能进行了观察、测试。时效初期,合金的强度快速增加,随着时效时间延长,增长趋势放缓;155℃时效12 h后,合金的抗拉强度、屈服强度分别由固溶态的266.7、161.7 MPa增长到333.3、272.3 MPa。合金的断后伸长率则随着时效时间的增加不断下降,由固溶态的12.00%降至155℃时效12 h后的7.00%。时效温度越高,原子扩散驱动力越大,合金的强度增加得越快,达到峰值所需得时间越短,同时断后伸长率也降低得越快。合金强度增加、断后伸长率降低的原因为Mg、Si原子偏聚,并逐渐形成稳定的Mg2Si相。随着第二相的析出转变,其与基体的共格程度逐渐降低,第二相与基体保持半共格关系时,合金的强度最大。

关键词： ZL114A合金时效处理低压铸造力学性能显微组织

不同空气流量下纯钨电极短电弧脉冲放电过程研究

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制造技术与机床 2024年第8期 42-48页

作者：鲁文峰李雪芝汪兵兵张兆明辛少坤新疆大学智能制造现代产业学院新疆乌鲁木齐830017 昌吉学院航空学院新疆昌吉831100

为进一步探索空气中短电弧加工(short electric arc machining, SEAM)放电过程,揭示短电弧放电加工中凹坑形成和材料去除机制,以空气作为介质,探究0 L/min和20 L/min空气流量对电弧-熔池和材料去除过程的影响,并进行对比试验研究。结果... 详细信息

为进一步探索空气中短电弧加工(short electric arc machining, SEAM)放电过程,揭示短电弧放电加工中凹坑形成和材料去除机制,以空气作为介质,探究0 L/min和20 L/min空气流量对电弧-熔池和材料去除过程的影响,并进行对比试验研究。结果表明,脉冲持续时间内,电弧经历快速膨胀、变形膨胀、稳定和熄灭4个阶段。在电弧膨胀阶段,材料以蚀除颗粒去除为主;在电弧稳定阶段,材料以熔融物与蚀除颗粒去除为主;在放电后续熄灭阶段,材料以熔融物去除为主。此外,连续脉冲放电中容易产生爆炸力,进一步增加金属材料去除量。提高空气流量可增大去除颗粒体积和抑制裂纹产生。

关键词：短电弧加工纯钨电极脉冲放电电弧-熔池凹坑

The distribution of dimethylcarbazoles in oils from the Pearl River Mouth Basin, South China Sea

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Chinese Journal Of Geochemistry 2007年第3期26卷 301-304页

作者： ZHANG Chunming ZHAO Hongjing GAO Kunshun YANG shaokun Key Laboratory of Exploration Technologies for Oil and Gas Resources （Yangtze University） Ministry of Education Jingzhou 434023 China Department of Geochemistry Yangtze University Jingzhou 434023 China Bohai Oil Research Institute of Bohai Oil Production Technology ＆ Service Company Tianjin 300452 China China National Offshore Oil Corporation Beijing I00027 China

C2-carbazole isomers have been investigated in crude oils from the Hui-Liu Structure Ridge (HLSR) in the Pearl River Mouth Basin (PRMB), South China Sea. The NH shielded isomer, as well as the NH partially shielded isomers, was detected in high abundance and the NH exposed isomers in lower abundance. A small-enrichment trend of 1,8-dimethylcarbazole (DMC) was observed in crude oils along the western part of HLSR (WPHLSR), which may indicate little effect of migration on the C2-carbazole distributions. Two strikingly different distribution patterns of NH partially shielded isomers were observed in the reservoirs along the WPHLSR: one with a preference of 1,3- and 1,6-DMCs and the other with a preference of 1,4- and 1,5-DMCs. All of the oils occurring in the Upper reservoirs have a preference of 1,3- and 1,6-DMCs, whereas those trapped in the Lower reservoirs show a preference of 1,4- and 1,5-DMCs, which may indicate there are two petroleum migration systems in the WPHLSR.

关键词：石油氮化合物珠江流域南海

电脉冲对9SiCr钢超声滚压表面性能的影响

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表面技术 2024年第19期53卷 186-192页

作者：徐梓真赵天永彭绍坤王猛赵洪甲宁腾飞马浩阳吴鹤石家庄海山实业发展总公司石家庄050200

目的提高9SiCr钢表面硬度、光洁度,获得更好的表面质量。方法对9SiCr钢棒状试样进行车削加工,然后分别进行不同参数下的超声滚压(USRP)和高能电脉冲辅助超声滚压(EP-USRP)加工。通过表面粗糙度测试、微观形貌分析、表层显微维氏硬度测试... 详细信息

目的提高9SiCr钢表面硬度、光洁度,获得更好的表面质量。方法对9SiCr钢棒状试样进行车削加工,然后分别进行不同参数下的超声滚压(USRP)和高能电脉冲辅助超声滚压(EP-USRP)加工。通过表面粗糙度测试、微观形貌分析、表层显微维氏硬度测试,分别评价不同加工状态试样的表面粗糙度、表面形貌、表层一定深度内的硬度梯度分布,并通过光学显微镜和扫描电子显微镜对试样表层形貌进行分析。结果车削后试样的表面粗糙度为0.45μm,经施加压力为1000 N的USRP加工后,试样表面粗糙度为0.043μm,对试样进行EP-USRP加工,当均方根电流密度为0.71 A/mm^(2)时,表面粗糙度降至0.032μm,比单纯USRP加工后试样的表面粗糙度降低了25.6%。经车削后,试样的显微维氏硬度约为550HV,经施加压力为800 N的USRP加工后,试样表层硬度为590HV。当对试样施加均方根电流密度为0.71 A/mm^(2)的EP-USRP处理后,其硬度为612HV,比USRP加工后的硬度增加了3.8%。从硬化层深度来看,经USRP加工后试样径向表层到心部大概有300μm得到硬化,而经EP-USRP加工后硬化层的深度可以增至400μm。从微观形貌分析可以看出,试样表层具有一定深度的细晶层,随着加工状态的不同,晶粒大小和细晶层深度也不同。结论采用USRP、EP-USRP加工都可以在一定程度上提高9SiCr钢的表面质量,电脉冲可以提高USRP加工的效果,进一步提高表面质量。

关键词：电脉冲超声滚压 9SiCr钢粗糙度显微硬度表面质量

Numerical Simulation of Stress Field in Physical Tempering Process of Flat Soda Lime Silica Glass

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 20-30页

作者：刘超英 HE Dongsheng OU Yingchun HE Feng HAO Lizi XU shaokun MA Juanrong China Building Materials Academy Beijing 100024China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China China Helicopter Research and Development Institute Jingdezhen 333001China

Based on the analysis of different theory for glass tempering process,the“structural theory”with stress relaxation and structural relaxation effects was selected to investigate the tempering of flat glass *** geometrical model with small size and non-homogeneous mesh were considered to build the finite element models according to the characteristics of stress *** tempering process of flat glass with12 mm thickness was calculated with the verified finite element *** transient and permanent stress of the central area,edge and corner end of the flat glass are obtained and *** the calculation results of basic case,the transient tensile stress at the upper surface of the central area,the center point of edge,the edge of edge,the edge of corner were 14.30,18.94,40.76 and 34.75 MPa,*** transient tensile stress at these points were dangerous to promote the glass to break during the *** addition,the point at the diagonal line of symmetry plane in the thickness direction,which is 14 mm from corner,has the maximum permanent tensile stress about 70.01 MPa in the flat glass after ***,it is indicated that the corner is the weakest region in the tempered glass.

关键词： nite element tempering stress relaxation structural relaxation compressive stress tensile stress

Land cover changes and the effects of cultivation on soil properties in Shelihu wetland,Horqin Sandy Land,Northern China

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Journal of Arid Land 2013年第1期5卷 71-79页

作者： Jie LIANI XueYong ZHAO XiaoAn ZUO shaokun WANG XinYuan WANG YongQing LUO Naiman Desertification Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China

Land cover change plays an essential role in the alternation of soils properties. By field investigation and applying satellite images, land cover information in the Shelihu wetland was carried out in an area of 2,819 hm2 in 1985, 1995, 2000, 2005, 2010 and 2011, respectively, in Horqin Sandy Land. A total of 57 soil sampling sites across Shelihu were chosen in wet meadow （CL0）, cropland （CL） and sandy land （SL） according to the spatial characteristics of water body change. Soil texture, organic carbon （SOC）, total nitrogen （TN） and total phosphorus （TP） contents, electrical conductivity （EC） and pH were measured at the soil depths of 0-10, 10-20 and 20-40 cm to examine the influence of agricultural conversion and continuous cultivation on soil properties. The results showed that the study area was covered by water body in 1985, which gradually declined afterwards and then reclaimed rapidly at a mean annual rate of 132.1 hm2/a from wet meadow to cropland since 1995. In 2011, water body was drained and the area was occupied by 10.8% of CL0, 76.9% of CL and 12.3% of SL. Large amounts of SOC, TN and TP were accumulated in the above depths in CL0. Soil in CL0 also had higher EC and silt and clay fractions, lower pH than in SL and CL. Soil in SL was seriously degraded with lower contents of SOC, TN and TP than in CL and CL0. SOC, TN content and EC in CL decreased with the increase of cultivation age, while pH showed a reverse trend with significance at plough horizon. The agricultural conversion in Shelihu was driven by the comprehensive factors of precipitation reduction, economic development and intense competitions for irrigation water. Continuous cultivation in this process is not sustainable because of SOC degradation and nutrient content reduction. The key point is that conventional tillage and removal of residuals induced further land degradation. Wetland reclamation for immediate economic interests led to greater costs in the long-term environmental restoration i

关键词： wetland soil degradation wetland reclamation continuous cultivation Horqin Sandy Land

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可调谐脉宽的全固态自锁模突发脉冲激光器

光通信技术 2024年第4期48卷 58-62页

作者：厉泽荣胡淼许蒙蒙王劭昆周雪芳毕美华杭州电子科技大学通信工程学院杭州310018

针对目前脉冲激光器产生突发脉冲功率低、装置复杂等问题,设计一种可调谐脉宽的全固态自锁模突发脉冲激光器,理论分析了腔内法布里-珀罗(F-P)结构的自锁模激光器的突发脉冲产生机理,建立了自锁模突发脉冲激光器的理论模型。实验结果表明... 详细信息

针对目前脉冲激光器产生突发脉冲功率低、装置复杂等问题,设计一种可调谐脉宽的全固态自锁模突发脉冲激光器,理论分析了腔内法布里-珀罗(F-P)结构的自锁模激光器的突发脉冲产生机理,建立了自锁模突发脉冲激光器的理论模型。实验结果表明:随着激光晶体长度的增加,突发脉冲的脉宽变宽;当激光晶体长度为5 mm、泵浦光功率为5.5 W时,获得了光束质量因子为1.42的突发脉冲,突发脉冲的重复频率为13.64 GHz,最大平均输出功率0.78 W,对应的斜效率和光光转化率分别为9.57%和8.73%。

关键词：自锁模激光器 Nd:YVO_(4) 突发脉冲纵模模式分布