检索结果-南通市图书馆

Synthesis of lutetium hydrides at high pressures

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2025年第1期10卷 98-104页

作者： Yuan-Ao peng Han-Yu Wang Fu-Hai Su pu Wang Hai-An Xu Lin Liu Lun-Xuan Yu Ross T.Howie Wan Xu Eugene Gregoryanz Xiao-Di Liu University of Science and Technology of China Hefei 230026China Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Centre for Science at Extreme Conditions and School of Physics and Astronomy University of EdinburghEdinburgh EH93FDUnited Kingdom Center for High Pressure Science and Technology Advanced Research Shanghai 201203China

High-pressure synthesis of lutetium hydrides from molecular hydrogen(H_(2))and lutetium(Lu)is systematically investigated using synchrotron X-ray diffraction,Raman spectroscopy,and visual *** demonstrate that the reaction pathway between H_(2)and Lu invariably follows the sequence Lu→LuH_(2)→LuH_(3)and exhibits a notable time dependence.A comprehensive diagram representing the formation and synthesis of lutetium hydrides as a function of pressure and time is *** findings indicate that the synthesis can be accelerated by elevated temperature and decelerated by increased ***,two critical pressure thresholds at ambient temperature are identified:the synthesis of LuH_(2)from Lu commences at a minimum pressure of~3 GPa,while~28 GPa is the minimum pressure at which LuH_(2)fails to transform into LuH_(3)within a time scale of *** underscores the significant impact of temporal factors on synthesis,with the reaction completion time increasing sub-linearly with rising ***,the cubic phase of LuH_(3)can be obtained exclusively through compressing the trigonal LuH_(3)phase at~11.5 *** also demonstrate that the bandgap of LuH_(3)slowly closes under pressure and is noticeably lower than that of LuH_(2).

关键词： synthesis ambient representing

维普期刊数据库

Workshop Structure Design of Frozen Drinks Factory

在线全文

学校读者我要写书评

暂无评论

Asian Agricultural Research 2025年第2期17卷 38-40,44页

作者： peng WAN Zhen zhao Guoyan WEN Yunshuang FU Xiaoli WU Cuizhi LI Zhiyong LU Inner Mongolia Yili Industrial Group Co. Ltd.Hohhot 010110China Key Laboratory of Cattle and Sheep Milk and Meat Products Risk Control and Key Technology State Administration for Market RegulationHohhot 010110China

According to the announcement of General Administration of Quality Supervision,Inspection and Quarantine of the People's Republic of China,the risk of microbial items in frozen drinks is very high,and it is difficult to *** example,a recent spot check showed that 42 kinds of frozen drinks had microbial indicators exceeding the *** of the reason is that the design of the production workshop is not conducive to the rapid removal of production water,resulting in continuous moisture throughout the workshop,which provides a breeding bed for microorganisms to breed and then contaminates the ***,research is carried out from the design point of view to fundamentally reduce the moisture in the workshop and build a dry workshop for frozen drinks production,so as to effectively reduce the risk of microbial contamination of frozen drinks.

关键词： Frozen drinks Microorganisms Structural design

农业社会化服务结构性失衡及影响因素研究——基于新疆棉区例证

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国农机化学报 2025年第2期46卷 326-336页

作者：蒲娟余国新赵向豪曹冲新疆农业大学经济管理学院乌鲁木齐市830052 新疆财经大学经济学院乌鲁木齐市830012 皖西学院经济与管理学院安徽六安237012

农业社会化服务作为小农户和现代农业有机衔接的纽带,对推动我国棉花生产向高质量迈进,实现农业农村现代化有重要作用。基于供求理论构建农业社会化服务结构性供需失衡的理论分析框架,结合新疆棉区的调查数据,采用因子分析和结构方程模... 详细信息

农业社会化服务作为小农户和现代农业有机衔接的纽带,对推动我国棉花生产向高质量迈进,实现农业农村现代化有重要作用。基于供求理论构建农业社会化服务结构性供需失衡的理论分析框架,结合新疆棉区的调查数据,采用因子分析和结构方程模型,从农户视域出发对农业社会化服务结构性供需失衡影响因素进行探究。结果表明:农业社会化服务存在供给主体和服务内容失衡,而渠道失衡不明显;农户禀赋、供给评价及心理需求均对农业社会化服务结构性供需失衡产生正向影响,影响程度由大到小排序为供给评价、农户禀赋、心理需求;族别、所在棉区、种植规模、各项服务评价及需求程度等因素均对社会化服务结构性供需失衡影响突出。鉴于此,提出坚持以为农服务为核心,建立“互联网+农户+农业社会化服务”模式,构建“全程一体化—组织协同—可持续”的服务供应链,深化农业社会化服务结构性改革等对策建议。

关键词：新疆棉区农业社会化服务结构性供需失衡供需理论结构方程模型

维普期刊数据库博看期刊

Effects of Temperature on Functional Response of Anagrus nilaparvatae Pang et Wang (Hymenoptera:Mymaridae) on the Eggs of Whitebacked Planthopper,Sogatella furcifera Horvth and Brown Planthopper,Nilaparvata lugens Stl

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2012年第8期11卷 1313-1320页

作者： MA Ming-yong peng zhao-pu HE Yuan Institute of Plant Protection Hunan Academy of Agricultural Sciences Changsha 412002 P.R.China Key Laboratory of Monitoring and Management of Plant Diseases and lnsects Ministry of Agriculture Nanjing Agricultural University Nanjing 210095 P.R. China

Understanding the temperature affecting parasitic efficiency is critical to succeed in utilizing parasitoid as natural enemy in pest management. Laboratory studies were carried out to determine the effects of temperature on parasitoid preference of female Anagrus nilaparvatae Pang et Wang （Hymenoptera：Mymaridae） to the eggs of whitebacked planthopper （WBPH）, Sogatella furcifera Horváth and brown planthopper （BPH）, Nilaparvata lugens Stl to build a composite model describing changes in parasitic response along a temperature gradient （18, 22, 26, 30, 34°C）. The results showed that attack responses of A. nilaparvatae on WBPH and BPH were the best described by a Type II functional response. The two parameters, attack rates （a） and handling times （Th）, of A. nilaparvatae to both eggs were influenced by the temperature. The maximum attack rates to WBPH （1.235） and BPH （1.049） were at 26 and 34°C, respectively, and the shortest handling times to WBPH （0.063） and BPH （0.057） were at 30 and 26°C, respectively. However, the optimal temperature for parasitic efficiency of A. nilaparvatae to WBPH and BPH eggs was both at 26°C, which showed that the present microclimate temperature of the habitat in the paddyfield was beneficial to A. nilaparvatae and indicated that parasitic efficiency of A. nilaparvatae would be impaired by global warming.

关键词： functional response temperature Anagrus nilaparvatae whitebacked planthopper brown planthopper

维普期刊数据库

Distinct ultrafast dynamics of bilayer and trilayer nickelate superconductors regarding the density-wave-like transitions

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2025年第2期70卷 180-186页

作者： Yidian Li Yantao Cao Liangyang Liu Pai peng Hao Lin Cuiying Pei Mingxin Zhang Heng Wu Xian Du Wenxuan zhao Kaiyi Zhai Xuefeng Zhang Jinkui zhao Miaoling Lin Pingheng Tan Yanpeng Qi Gang Li Hanjie Guo Luyi Yang Lexian Yang State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Key Lab for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China Songshan Lake Materials Laboratory Dongguan 523808China School of Physical Science and Technology ShanghaiTech University and CAS-Shanghai Science Research CenterShanghai 201210China State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China ShanghaiTech Laboratory for Topological Physics Shanghai 200031China Laboratory of High-resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210China Frontier Science Center for Quantum Information Beijing 100084China

In addition to the pressurized high-temperature superconductivity,bilayer and trilayer nickelate superconductors La_(n+1)Ni_nO_(3n+1)(n=2 and 3)exhibit many intriguing properties at ambient pressure,such as orbital-dependent electronic correlation,non-Fermi liquid behavior,and density-wave ***,using ultrafast reflectivity measurement,we observe a drastic difference between the ultrafast dynamics of the bilayer and trilayer nickelates at ambient *** observe a coherent phonon mode in La_(4)Ni_(3)O_(10)involving the collective vibration of La,Ni,and O atoms,which is absent in La_(3)Ni_(2)O_(7).Temperature-dependent relaxation time diverges near the density-wave transition temperature of La_(4)Ni_(3)O_(10),while it is inversely proportional to the temperature in La_(3)Ni_(2)O_(7)above~150 K,suggesting a non-Fermi liquid behavior of La_(3)Ni_(2)O_(7).Moreover,we estimate the electron–phonon coupling constants to be 0.05–0.07 and 0.12–0.16 for La_(3)Ni_(2)O_(7)and La_(4)Ni_(3)O_(10),respectively,suggesting a relatively minor role of electron–phonon coupling in the electronic properties of La_(n+1)Ni_nO_(3n+1)at ambient *** relevant microscopic interaction and dynamic information are essential for further studying the interplay between superconductivity and density-wave transitions in nickelate superconductors.

关键词： Nickelate superconductors Density-wave state Ultrafast dynamics Electron-phonon coupling Coherent phonon

Temporal-specific single-cell atlas of human type A aortic dissection reveals immune cell dynamics and therapeutic targets

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2025年第2期70卷 167-171页

作者： Wenting zhao Juan Chen Yi Xia Zhixi Wei Sitong Wan Huiyuan Guo Yanling Hao Wenjian Jiang Hongjia Zhang Fazheng Ren peng An Yongting Luo Junjie Luo Department of Nutrition and Health China Agricultural UniversityBeijing 100193China Department of Cardiovascular Surgery Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

Stanford type A aortic dissection(STAAD/AD)is a degenerative aortic remodeling disease with an extremely high mortality rate and poor prognosis[1,2].Dissections can be classified into acute(90 d)stages depending on the time interval between the onset of initial symptoms and presentations[3].Patients who survive the acute phase progress to subacute and ultimately chronic stages[4,5].

关键词： dissection acute aortic

Transcription coactivator YAP1 promotes CCND1/CDK6 expression, stimulating cell proliferation in cloned cattle placentas

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2025年第01期 122-138页

作者： Shan-Shan Wu Xiao-Yu zhao Lei Yang Chao Hai Di Wu Xue-Fei Liu Li-Shuang Song Chun-Ling Bai Guang-Hua Su Guang-peng Li State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL) Inner Mongolia University College of Life Sciences Inner Mongolia University

Somatic cell nuclear transfer(SCNT) has been successfully employed across various mammalian species,yet cloned animals consistently exhibit low pregnancy rates, primarily due to placental abnormalities such as hyperplasia and hypertrophy. This study investigated the involvement of the Hippo signaling pathway in aberrant placentaldevelopmentinSCNT-inducedbovine pregnancies. SCNT-derived cattle exhibited placental hypertrophy, including enlarged abdominal circumference and altered placental cotyledon morphology. RNA sequencing analysis indicated significant dysregulation of Hippo signaling pathway genes in SCNT placentas. Coexpression of YAP1 and CCND1 was observed in cloned blastocysts, placental tissues, and bovine placental mesenchymal stem cells(bPMSCs). Manipulation of YAP1expression demonstrated the capacity to regulate bPMSC proliferation. Experimental assays confirmed the direct binding of YAP1 to CCND1, which subsequently promoted CCND1 expression in bPMSCs. Furthermore, inhibition of CDK6, a downstream target of CCND1, attenuated SCNT bPMSC proliferation. This study identified YAP1 as a key regulatory component within the Hippo signaling pathway that drives placental hyperplasia in cloned cattle through up-regulation of CCND1-CDK6 expression, facilitating cell cycle progression. These findings offer potential avenues for enhancing cloning efficiency, with implications for evolutionary biology and the conservation of valuable germplasm resources.

关键词：

面向自动驾驶汽车的新型转向系统设计及仿真分析

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

系统仿真学报 2025年第1期37卷 211-219页

作者：姬鹏赵金鹏姜利民河北工程大学机械与装备工程学院河北邯郸056038

针对目前由于法规要求和技术成熟度的限制,面向自动驾驶汽车的转向系统必须具备驾驶员接管功能的需求,将永磁耦合装置嵌入转向系统中,设计出一款新型转向系统,可实现自动驾驶模式和驾驶员接管模式的切换。对新型转向系统进行整体方案设... 详细信息

针对目前由于法规要求和技术成熟度的限制,面向自动驾驶汽车的转向系统必须具备驾驶员接管功能的需求,将永磁耦合装置嵌入转向系统中,设计出一款新型转向系统,可实现自动驾驶模式和驾驶员接管模式的切换。对新型转向系统进行整体方案设计,该系统能够实现转向盘静默、路感模拟、过载保护和机械转向冗余等功能,在不增加额外硬件的情况下实现转向系统的冗余设计。对该系统的关键部件永磁耦合装置开展了仿真分析和台架测试,对其传递特性进行了研究。搭建了整车和转向系统模型。通过Simulink-CarSim-PreScan联合仿真对新型转向系统进行功能分析,验证了该系统功能安全和冗余设计的有效性。

关键词：自动驾驶转向系统永磁耦合装置模式切换冗余设计

维普期刊数据库博看期刊

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

关键词：