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隐身直升机红外辐射与雷达散射特征分析

直升机技术 2024年第2期 14-21页

作者：王磊单勇张靖周陈新蕾南京航空航天大学能源与动力学院进排气技术教育部重点实验室江苏南京210016 南京航空航天大学电子信息工程学院/集成电路学院江苏南京210016

为实现直升机红外/雷达综合隐身,将一体化红外抑制器融入隐身直升机的设计中,通过数值计算得到悬停状态下直升机的温度场、红外辐射特性以及雷达散射特性。结果表明:在一体化红外抑制器引射气流和旋翼下洗气流的作用下,直升机排气混合... 详细信息

为实现直升机红外/雷达综合隐身,将一体化红外抑制器融入隐身直升机的设计中,通过数值计算得到悬停状态下直升机的温度场、红外辐射特性以及雷达散射特性。结果表明:在一体化红外抑制器引射气流和旋翼下洗气流的作用下,直升机排气混合管和后机身都可以得到很好的冷却;尾桨通流作用下的高温排气对左侧机身的局部加热效应更显著;排气系统与后机身一体化设计方案使得机身可以有效地遮挡高温混合管,所以3~5μm波段总红外辐射主要来源于气体和机身蒙皮;而在8~14μm波段,气体红外辐射可以忽略不计;在3 GHz、6 GHz、10 GHz和15 GHz频率下,隐身直升机周向RCS均值都控制在4 dBsm以下,表明一体化设计方案在降低红外辐射的同时也具备较好的雷达隐身能力。

关键词：直升机一体化红外抑制器红外隐身雷达隐身

Expression of steroidogenic acute regulatory protein and its regulation by interferon-gamma in rat corpus luteum

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Chinese Science Bulletin 2000年第23期45卷 2152-2157页

作者： Hongjuan Gao xinlei chen Lei Shi Yixun Liu Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

The steroidogenic acute regulatory protein (StAR) is the key regulatory protein of steroidogenesis. De novo synthesis of StAR protein is required for intramitochondrial translocation of cholesterol to the cytochrome P450 side chain cleavage enzyme which is located on the matrix side of the inner mitochondrial membrane. This is the rate-limiting step of steroid biosynthesis. Using in situ hybridization and immunohistochemistry we studied StAR expression in various stages of the corpora luteal and its regulation by interferon-gamma (IFNγ) in the adult pseudopregnant rat. The results indicated that expression of StAR in the corpora luteal was correlated with progesteron production and IFNγ was capable of inhibiting its expression.

关键词： corpus luteum StAR in situ hybridization immunohistochemistry IFNγ.

紫锥菊提取物对SD大鼠心肌组织氧化应激的保护作用

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中国兽医学报 2024年第1期44卷 141-149页

作者：刘波吴华刘嘉华行倩文陈鑫磊王文胜青海大学农牧学院青海西宁810016

为探究紫锥菊提取物对SD大鼠心肌组织氧化应激的保护作用及相关蛋白表达的影响。选择60只SD大鼠按照随机分组方法分成对照组、不同质量浓度组(10、20、40 mg/kg),每组15只,进行饲养试验。饲养结束后,麻醉并取出心脏,检测心肌组织各生化... 详细信息

为探究紫锥菊提取物对SD大鼠心肌组织氧化应激的保护作用及相关蛋白表达的影响。选择60只SD大鼠按照随机分组方法分成对照组、不同质量浓度组(10、20、40 mg/kg),每组15只,进行饲养试验。饲养结束后,麻醉并取出心脏,检测心肌组织各生化指标及免疫组织化学染色对心肌组织做病理检测。SD大鼠随着添加紫锥菊提取物浓度增加,SD大鼠氧化应激指标ROS含量和MDA含量呈现逐渐降低的趋势,添加10、20、40 mg/kg紫锥菊提取物组SD大鼠ROS和MDA显著低于对照组(P0.05),但有降低的趋势。结果表明,紫锥菊提取物可通过调控SD大鼠心肌组织代谢,增强其抗氧化能力、线粒体功能、能量代谢水平,提高SD大鼠适应能力,且以SD大鼠添加40 mg/kg紫锥菊提取物作用最佳。

关键词：紫锥菊提取物心肌组织低氧适应抗氧化

不同夜间温度条件下外源水杨酸对大豆产量的调控作用

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大豆科学 2024年第4期43卷 439-449页

作者：张仲法宋雯雯徐彩龙陈新蕾吴佩杭王书君陈磊吴存祥烟台大学生命科学学院山东烟台264005 中国农业科学院作物科学研究所/国家大豆产业技术研发中心北京100081

在全球气候变暖的背景下,夜间高温成为大豆高产的不利因素之一。水杨酸(Salicylic Acid,SA)是一种重要的植物激素,外源喷施SA可提升植物应对高温干旱等逆境的能力。为探究夜间高温危害的应对措施,选用2种生育期相近的大豆品种中黄39和中... 详细信息

在全球气候变暖的背景下,夜间高温成为大豆高产的不利因素之一。水杨酸(Salicylic Acid,SA)是一种重要的植物激素,外源喷施SA可提升植物应对高温干旱等逆境的能力。为探究夜间高温危害的应对措施,选用2种生育期相近的大豆品种中黄39和中黄76,设置3个夜间温度(T1:18℃;T2:23℃;T3:28℃),每个夜间温度下设置3个SA浓度处理(SA0:CK;SA1:0.1 mmol·L^(-1) SA;SA2:0.5 mmol·L^(-1) SA)。探讨外源SA对鼓粒期夜间温度升高环境下大豆产量的调控作用。结果表明:与T1+CK处理相比,夜间温度升高,大豆单株荚数、单株粒数、地上部干物质、产量和收获指数均下降,中黄39和中黄76产量分别降低6.34%~27.13%和14.99%~45.66%。夜间温度升高,喷施SA可显著提高大豆净光合速率、地上部干物质、单株荚数和粒数,降低呼吸强度,使产量和收获指数显著提升,中黄39和中黄76表现一致。其中,28℃夜间温度条件下,喷施SA处理大豆产量增幅达45.69%~48.55%。研究结果表明,外施SA可以在一定程度上缓解夜间高温造成的大豆产量损失,提高收获指数。

关键词：大豆夜间温度水杨酸产量收获指数

Grouting-induced ground heave and building damage in tunnel construction:A case study of Shenzhen metro

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Underground Space 2022年第6期7卷 1175-1191页

作者： Zonglei Dong Xuemin Zhang chenxi Tong xinlei chen Han Feng Sheng Zhang School of Civil Engineering Central South UniversityChangsha 410075China

This paper presents a case study of the grouting-induced ground heave and building damage in the tunnel construction of Shenzhen Metro Line 10,which passes through a crowded urban area with water-rich strata in Shenzhen,the province of Guangdong,*** was reported that the ground surface heave of up to approximately 500 mm was observed,and the customs building above the tunnels was seriously damaged because of a 200 mm *** a significant heave was closely associated with the advanced curtain grouting adopted in the tunnel *** this end,the heave of the ground surface and the displacement and deformation of the customs building were *** discrete element method(DEM)was then used to qualitatively analyze the relations between the grouting parameters and the ground *** results demonstrated that the poor dewatering work in the early stages increased the difficulty of *** grouting materials with high viscosity and large grouting pressure were required for water blocking because of the large amount of confined water in the tunnel,resulting in fracture *** ground was then uplifted due to the large inflow of the slurry and the excess pore water ***,the lessons learned from this incident were *** presented case study provides a reference for tunnel construction in urban areas with water-rich strata.

关键词： Grouting Ground heave Building damage Field test Numerical simulation

低氧环境紫锥菊提取物-菊苣酸通过PPAR信号通路对SD大鼠肝脏组织脂肪合成的影响

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中国兽医学报 2024年第1期44卷 135-140页

作者：行倩文吴华刘嘉华刘波张龙飞陈鑫磊马欣茹青海大学农牧学院青海西宁810016

为探究紫锥菊提取物-菊苣酸在低氧环境下影响SD大鼠肝脏脂肪代谢的分子机制。选取60只健康雄性SD大鼠(6~8周龄,(192±7.35)g)(P>0.05),适应性喂养2周后,随机分为对照组、不同浓度CA组(10、20、40 mg/kg),每组15只,连续灌胃49 d。4组大... 详细信息

为探究紫锥菊提取物-菊苣酸在低氧环境下影响SD大鼠肝脏脂肪代谢的分子机制。选取60只健康雄性SD大鼠(6~8周龄,(192±7.35)g)(P>0.05),适应性喂养2周后,随机分为对照组、不同浓度CA组(10、20、40 mg/kg),每组15只,连续灌胃49 d。4组大鼠均自由采食和饮水,灌胃第50天对SD大鼠进行麻醉处理后,采集肝脏组织,并通过油红O染色法计算各组大鼠肝脏组织油滴面积占总面积的百分比以及测定PPAR信号通路关键因子PLIN2、PLIN5、PPARα、PPARγ、RXRα的表达情况。油红O染色结果显示:与对照组相比,添加紫锥菊提取物-菊苣酸组极显著降低油红O染色面积(P<0.01);PPAR信号通路关键因子表达结果显示:与对照组相比,添加紫锥菊提取物-菊苣酸组显著降低PLIN2、PLIN5、PPARα、PPARγ、RXRα的mRNA及蛋白表达量(P<0.05),其中以添加10 mg/kg紫锥菊提取物-菊苣酸组对PLIN2、PLIN5、PPARα、PPARγ、RXRα的mRNA及蛋白表达量效果最显著(P<0.05)。结果表明,紫锥菊提取物-菊苣酸降低脂肪合成相关因子的表达,调控脂肪的合成与储存,预防脂肪的过多累积导致机体脂质代谢紊乱,紫锥菊提取物-菊苣酸改善了低氧诱导的脂质代谢功能障碍,且10 mg/kg组作用效果最好。本研究为紫锥菊提取物-菊苣酸作为高海拔地区预防高原动物脂质代谢紊乱的饲料添加剂的开发利用提供了理论基础。

关键词：低氧菊苣酸 SD大鼠肝脏组织油红O PPAR信号通路脂肪合成

Temporal and spatial expression of MMP-2,-9,-14 and their inhibitors TIMP-1,-2,-3 in the corpus luteum of the cycling rhesus monkey

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Science China(Life Sciences) 2006年第1期49卷 37-45页

作者： chen xinlei GAO Hongjuan GAO Fei WEI Peng HU Zhaoyuan LIU Yixun State Key Laboratory of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100080China

The corpus luteum(CL)is a transient endocrine organ that secretes progesterone to support early *** implantation is unsuccessful,luteolysis is *** tissue re-modeling occurs during CL formation and *** this study,we have studied the possible in-volvement of MMP-2,-9,-14,and their inhibitors,TIMP-1,-2,-3 in the CL of cycling rhesus monkey at various stages by in situ hybridization,immunohistochemistry and microscopic *** re-sults showed that the MMP-2 mRNA and protein were mainly expressed in the endothelial cells at the early and middle stages of the CL development,while their expressions were observed in the luteal cells at the late stage during luteal ***-9 protein was detected in the CL at the early and middle stages,and obviously increased at the late *** expressions of MMP-14 and TIMP-1 mRNA were high at the early and late stages,and low at the middle ***-2 mRNA was high throughout all the stages,the highest level could be observed at the late *** TIMP-3 produc-tion was detected throughout all the stages,but obviously declined during CL ***-9,-14 and TIMP-1,-2,-3 were mainly localized in the cytoplasm of the steroidogenic *** results suggest that the MMP/TIMP system is involved in regulation of CL development in the primate,and the coordinated expression of MMP-2,-14 and TIMP-1,-3 may have a potential role in the CL forma-tion and the functional maintaining,while the interaction of MMP-2,-9,-14 and TIMP-1,-2,-3 might also play a role in CL regression at the late stage of CL development in the primate.

关键词： MMP TIMP corpus luteum rhesus monkey

Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution

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Nano-Micro Letters 2024年第9期16卷 49-94页

作者： Xuan Wang Akang chen xinlei Wu Jiatao Zhang Jichen Dong Leining Zhang Key Laboratory of Cluster Science Ministry of Education of ChinaBeijing Key Laboratory of Photoelectronic and Electrophonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of Chemistry Chinese Academy of SciencesBeijing 100190People’s Republic of China

In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk *** controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various *** this context,the atomic substitution method has emerged as a favorable *** involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting *** this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC *** effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are *** enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these ***,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized.

关键词： Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis

Recent progress on the functionalization of white phosphorus in China

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National Science Review 2024年第06期11卷 308-320页

作者： xinlei Huangfu Zhongzhen Wang Yu chen Junnian Wei Wei Liu Wen-Xiong Zhang Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory of Rare-Earth Materials Chemistry and Applications & Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular Engineering Peking University

Direct synthesis of organophosphorus compounds from white phosphorus represents a significant but challenging subject, especially in the context of ongoing efforts to comprehensively improve the phosphorus-derived chemical industry driven by sustainability and safety concerns. China is the world's largest producer of white phosphorus, creating a significant demand for the green transformation of this crucial feedstock. This review provides an overview of advancements in white phosphorus activation by Chinese research teams, focusing on the direct construction of P–C/N/O/S/M bonds from white phosphorus. Additionally, we offer some insights into prospective directions for the activation and transformation of white phosphorus in the future. This review paper aims to attract more researchers to engage in this area, stimulating follow-up exploration and fostering enduring advances.

关键词： white phosphorus organophosphorus compound activation selectivity efficiency