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Research in Astronomy and Astrophysics 2021年第4期21卷 101-109页

作者： zhi-jun zhao Hai-Jing Zhou Yu-Chen Zhang Yun Ling Fang-Yu Xu School of Physics Henan Normal UniversityXinxiang 453007China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Kunming Institute of Physics Kunming 650216China Henan Key Laboratory of Infrared Materials&Spectrum Measures and Applications Xinxiang 453007China

In order to evaluate the ground-based infrared telescope sensitivity affected by the noise from the atmosphere,instruments and detectors,we construct a sensitivity model that can calculate limiting magnitudes and signal-to-noise ratio(S/N).The model is tested with tentative measurements of M’-band sky brightness and atmospheric extinction obtained at the Ali and Daocheng *** find that the noise caused by an excellent scientific detector and instruments at-135℃can be ignored compared to the M’-band sky background ***,when S/N=3 and total exposure time is 1 second for 10 m telescopes,the magnitude limited by the atmosphere is 13.01^(m)at Ali and 12.96^(m)at *** under lessthan-ideal circumstances,i.e.,the readout noise of a deep cryogenic detector is less than 200 e-and the instruments are cooled to below-87.2℃,the above magnitudes decrease by 0.056^(m)at ***,according to observational requirements with a large telescope in a given infrared band,astronomers can use this sensitivity model as a tool for guiding site surveys,detector selection and instrumental thermal-control.

关键词： methods:miscellaneous atmospheric effects telescopes site testing instrumentation:detectors instrumentation:miscellaneous

Mid-infrared atmospheric transmittance at 5100 m-altitude Ali Observatory

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Research in Astronomy and Astrophysics 2020年第8期20卷 316-322页

作者： Fei-Xiang Wang Fang-Yu Xu Jie Guo zhi-jun zhao Rui-Ting Hao Jian-Guo Xiao Yu-Chao Jia Shan-Jie Huang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Yunnan Key Laboratory of Optic-electronic Information Technology Yunnan Normal UniversityKunming 650092China Yunnan KIRO-CH Photonics Co.Ltd Kunming 650217China School of Physics Henan Normal UniversityXinxiang 453007China

Ali in Tibet,5100 m above sea level,is one of the most suitable locations in the world for infrared spectral *** atmospheric transmittances at Ali Observatory and Mauna Kea Observatory were calculated by MODTRAN using radiosonde *** results were 0.848 and 0.789 respectively which indicated better conditions at Ali Observatory.A self-made instrument with a 320×256-pixel HgCdTe infrared focal plane array and a 7.5-cm diameter telescope was utilized for the actual *** the help of standard stars,the on-site and real-time atmospheric transmittance can be obtained as 0.831 by fitting the relation between the measured atmospheric radiation intensity and the zenith angle based on radiation transfer *** paper firstly reports the atmospheric transmittance in the M'band(4.605–4.755μm)at the 5100 m-altitude Ali observatory by actual *** shows that the high-altitude Ali observatory with sufficiently low water vapor content is suitable for observation in the mid-infrared bands.

关键词： infrared atmospheric effects radiation mechanisms:thermal

The role of leptin in striped hamsters subjected to food restriction and refeeding

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Zoological Research 2014年第4期35卷 262-271页

作者： zhi-jun zhao Yong-An LIU Jing-Ya XING Mao-Lun ZHANG Xiao-Ying NI Jing CAO College of Life and Environmental Science Wenzhou University Wenzhou 325027 China School of Agricultural Science Liaocheng University Liaocheng 252059 China

Food restriction （FR） and refeeding （Re） have been suggested to impair body mass regulation and thereby making it easier to regain the lost weight and develop over-weight when FR ends. However, it is unclear if this is the case in small mammals showing seasonal forging behaviors. In the present study, energy budget, body fat and serum leptin level were measured in striped hamsters that were exposed to FR-Re. The effects of leptin on food intake, body fat and genes expressions of several hypothalamus neuropeptides were determined. Body mass, fat content and serum leptin level decreased during FR and then increased during Re. Leptin supplement significantly attenuated the increase in food intake during Re, decreased genes expressions of neuropepetide Y （NPY） and agouti-related protein （AgRP） of hypothalamus and leptin of white adipose tissue （WAT）. Hormone-sensitive lipase （HSL） gene expression of WAT increased in leptin-treated hamsters that were fed ad libitum, but decreased in FR-Re hamsters. This indicates that the adaptive regulation of WAT HSL gene expression may be involved in the mobilization of fat storage during Re, which partly contributes to the resistance to FR-Re-induced overweight. Leptin may be involved in the down regulations of hypothalamus orexigenic peptides gene expression and consequently plays a crucial role in controlling food intake when FR ends.

关键词： Body mass Food restriction Hypothalarnus neuropeptides Leptin Striped hamster

Energy intake, oxidative stress and antioxidant in mice during lactation

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Zoological Research 2015年第2期36卷 95-102页

作者： Guo-Xiao ZHENG Jiang-Tao LIN Wei-Hong ZHENG Jing CAO zhi-jun zhao College of Life and Environmental Science Wenzhou University

Reproduction is the highest energy demand period for small mammals, during which both energy intake and expenditure are increased to cope with elevated energy requirements of offspring growth and somatic protection. Oxidative stress life history theory proposed that reactive oxygen species（ROS） were produced in direct proportion to metabolic rate, resulting in oxidative stress and damage to macromolecules. In the present study, several markers of oxidative stress and antioxidants activities were examined in brain, liver, kidneys, skeletal muscle and small intestine in non-lactating（Non-Lac） and lactating（Lac） KM mice. Uncoupling protein（ucps） gene expression was examined in brain, liver and muscle. During peak lactation, gross energy intake was 254% higher in Lac mice than in Non-Lac mice. Levels of H2O2 of Lac mice were 17.7% higher in brain（P〈0.05）, but 21.1%（P〈0.01） and 14.5%（P〈0.05） lower in liver and small intestine than that of Non-Lac mice. Malonadialdehyde（MDA） levels of Lac mice were significantly higher in brain, but lower in liver, kidneys, muscle and small intestine than that of Non-Lac mice. Activity of glutathione peroxidase（GSH-PX） was significantly decreased in brain and liver in the Lac group compared with that in the Non-Lac group. Total antioxidant capacity（TAOC） activity of Lac mice was significantly higher in muscle, but lower in kidneys than Non-Lac mice. Ucp4 and ucp5 gene expression of brain was 394% and 577% higher in Lac mice than in Non-Lac mice. These findings suggest that KM mice show tissuedependent changes in both oxidative stress and antioxidants. Activities of antioxidants may be regulated physiologically in response to the elevated ROS production in several tissues during peak lactation. Regulations of brain ucp4 and ucp5 gene expression may be involved in the prevention of oxidative damage to the tissue.

关键词： Antioxidant Energy intake Lactation Metabolic rate Oxidative stress Uncoupling protein

The Experimental Study of the Dynamic Buckling of the Bar Subjected to Axial Impact

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The Experimental Study of the Dynamic Buckling of the Bar Su...

Molecular characteristics of Brucella melitensis isolates from humans in Qinghai Province, China

第八届全国冲击动力学学术讨论会

作者： HAN zhi-jun zhao Yong-gang ZHANG Shan-yuan Taiyuan University of Technology,Taiyuan,Shanxi,030024

The dynamic buckling of the elastic perfect columns under axial impact which one end is fixed,and the other end is clamped is studied *** on the outer trigger,the waveform of two strain gauges that are attached in symmetric pairs,on opposite columns faces near the peak of the column’s buckling mode is recorded by *** to measured stress and critical bifurcate time,critical buckling load is *** experimental results show that the dynamic critical load of the columns is distinctly greater than the static one under the same boundary conditions and the effect of stress wave plays an important part in the occurring and the growing of the buckling.

关键词： dynamic buckling bifurcation time the effect stress wave critical buckling load

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Infectious Diseases of Poverty 2021年第2期10卷 64-69页

作者： zhi-jun zhao Ji-Quan Li Li Ma Hong-Mei Xue Xu-Xin Yang Yuan-Bo zhao Yu-Min Qin Xiao-Wen Yang Dong-Ri Piao Hong-Yan zhao Guo-Zhong Tian Qiang LiJian-Ling Wang Guang Tian Hai Jiang Li-Qing Xu Qinghai Institute for Endemic Disease Prevention and Control The department of brucellosis prevention and controlXining 810021QinghaiChina State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Key Laboratory of Plague Prevention and Research Qinghai Institute for Endem ic Disease Prevention and ControlNational Health Commission(2019PT310004)and Key Laboratory for Plague Prevention and Control of Qinghai ProvinceXining 810021QinghaiChina.

Background:The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly,with confirmed cases distributed across 31 ***,the epidemiology of brucellosis transmission has not been fully *** characterize the infecting strains isolated from humans,multiple-locus variable-number tandem repeats analysis(MLVA)and whole-genome single-nucleotide polymorphism(SNP)-based approaches were ***:Strains were isolated from two males blood cultures that were confirmed Brucella m elitensis positive following biotyping and *** DNA was extracted from these two strains,and whole-genome sequencing was ***,SNP-based phylogenetic analysis was performed to compare the two strains to 94 *** strains(complete genome and draft genome)retrieved from online ***:The two Brucella isolates were identified as *** biovar 3(QH2019001 and QH2019005)following conventional biotyping and were found to have differences in their variable number tandem repeats(VNTRs)using *** examination assigned the 96 strains to five genotype groups,with QH2019001 and QH2019005 assigned to the same group,but different ***,the QH2019005 strain was assigned to a new subgenotype,llj,within genotype *** findings were then combined to determine the geographic origin of the two Brucella ***:Utilizing a whole-genome SNP-based approach enabled differences between the two B.m elitensis strains to be more clearly resolved,and facilitated the elucidation of their different evolutionary *** approach also revealed that QH2019005 is a member of a new subgenotype(Hj)with an ancient origin in the eastern Mediterranean Sea.

关键词： Brucella m elitensis Multiple-locus variable-number tandem repeats analysis Whole-genome sequencing Single-nucleotide polymorphism

纳米碳纤维负载磷氧化物催化剂催化丙烷氧化脱氢研究

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天然气化工—C1化学与化工 2005年第6期30卷 1-5,10页

作者：隋志军李平 zhao Tie-jun 赵铁均周静红戴迎春华东理工大学化学工程联合国家重点实验室上海200237

考察了纳米碳纤维(CNF)、活性炭、石墨以及CNF负载磷氧化物催化剂催化丙烷氧化脱氢(ODP)反应性能。采用SEM、HRTEM、XRD、TG和BET表征了催化剂的组成和结构。结果表明炭材料自身对于ODP过程具有较高的活性和选择性,尤其是CNF由于其独特... 详细信息

考察了纳米碳纤维(CNF)、活性炭、石墨以及CNF负载磷氧化物催化剂催化丙烷氧化脱氢(ODP)反应性能。采用SEM、HRTEM、XRD、TG和BET表征了催化剂的组成和结构。结果表明炭材料自身对于ODP过程具有较高的活性和选择性,尤其是CNF由于其独特的结构特点更适合用作ODP过程催化剂。负载磷氧化物提高了CNF催化剂的适用温度,并提高了丙烯产得率。以磷酸氢二铵为前驱体,负载于经液相氧化处理的CNF上可以得到高选择性的ODP过程催化剂,在500℃下,丙烷转化率为42.07%时,丙烯选择性达到39.63%。

关键词：纳米碳纤维磷氧化物催化丙烷氧化脱氢丙烯

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

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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.

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LiDAR-Visual SLAM with Integrated Semantic and Texture Information for Enhanced Ecological Monitoring Vehicle Localization

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Computers, Materials & Continua 2025年第1期82卷 1401-1416页

作者： Yiqing Lu Liutao zhao Qiankun zhao Foreign Environmental Cooperation Center Ministry of Ecology and Environment of PRCBeijing100035China Beijing Computing Center Co. Ltd.Beijing Academy of Science and TechnologyBeijing100083China Beijing Guyu Interactive Artificial Intelligence Application Co. Ltd.Beijing100024China

Ecological monitoring vehicles are equipped with a range of sensors and monitoring devices designed to gather data on ecological and environmental *** vehicles are crucial in various fields,including environmental science research,ecological and environmental monitoring projects,disaster response,and emergency management.A key method employed in these vehicles for achieving high-precision positioning is LiDAR(lightlaser detection and ranging)-Visual Simultaneous Localization and Mapping(SLAM).However,maintaining highprecision localization in complex scenarios,such as degraded environments or when dynamic objects are present,remains a significant *** address this issue,we integrate both semantic and texture information from LiDAR and cameras to enhance the robustness and efficiency of data ***,semantic information simplifies the modeling of scene elements,reducing the reliance on dense point clouds,which can be less ***,visual texture information complements LiDAR-Visual localization by providing additional contextual *** incorporating semantic and texture details frompaired images and point clouds,we significantly improve the quality of data association,thereby increasing the success rate of *** approach not only enhances the operational capabilities of ecological monitoring vehicles in complex environments but also contributes to improving the overall efficiency and effectiveness of ecological monitoring and environmental protection efforts.

关键词： LiDAR-Visual simultaneous localization and mapping integrated semantic texture information

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加压搅拌浸出体系下氧气的气含率

中国有色金属学报 2017年第3期27卷 655-665页

作者：田磊刘燕吕国志唐俊杰赵秋月张廷安东北大学多金属共生矿生态化冶金教育部重点实验室沈阳110819

硫化矿加压浸出体系的氧化过程主要在液相内进行,氧气的气含率对气液固三相反应的最终效果和有价金属的提取率具有重要意义。本研究使用透明石英高压釜和高速照相机等设备,在高温高压条件下,研究推进式搅拌桨工作过程中气液两相混合状... 详细信息

硫化矿加压浸出体系的氧化过程主要在液相内进行,氧气的气含率对气液固三相反应的最终效果和有价金属的提取率具有重要意义。本研究使用透明石英高压釜和高速照相机等设备,在高温高压条件下,研究推进式搅拌桨工作过程中气液两相混合状态和气泡在溶液中的行为规律。结果表明:当搅拌速度从400 r/min上升到550r/min,气含率从0.137%上升到1.58%;当温度从363 K增加到423 K时,气含率从1.22%降低到0.774%;当氧分压从0.2 MPa增加至0.8 MPa,气含率从0.997%降低到0.951%。最后,通过对实验数据进行因次分析,得出气含率的准数方程。

关键词：硫化矿加压浸出气含率因次分析准数方程