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非接触式张力线桥梁挠度测量系统

仪器仪表学报 2008年第5期29卷 1058-1062页

作者：蓝章礼杨小帆重庆交通大学计算机与信息学院重庆400074 重庆大学计算机学院重庆400044

短期和长期挠度的测量是了解和评估土木工程结构行为的必要途径。为精确测量桥梁挠度,提出了一种非接触式张力线桥梁挠度测量系统(NWSWS),该系统具有高精度、低成本、适合于不间断在线监测等优点。阐述了NWSWS的组成与测量原理,分析了... 详细信息

短期和长期挠度的测量是了解和评估土木工程结构行为的必要途径。为精确测量桥梁挠度,提出了一种非接触式张力线桥梁挠度测量系统(NWSWS),该系统具有高精度、低成本、适合于不间断在线监测等优点。阐述了NWSWS的组成与测量原理,分析了系统的测量精度和测量速度,根据系统的结构特点研究了系统可能产生误差的一些原因,对误差的大小进行了估算,提出了降低误差的应对方案。实验结果对该系统的性能进行了验证。目前该系统已运用于一座桥梁的在线挠度监测。

关键词：桥梁挠度测量张力线非接触

Molecular phylogeny of Bactrocera species （Diptera： Tephritidae） inferred from mitochondrial 16s rDNA sequences

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Journal of Agricultural Science and Technology 2009年第6期3卷 24-28页

作者： ZHANG Bin LIU Ying-hong WANG Ze-le ZHAO lan-lan Chongqing Key Laboratory of Entomology ＆ Insect Control Engineering College of Plant Protection Southwest University Chongqing 400013 China Chongqing Agriculture Technique Extension Station Chongqing 400013 China

The fruit flies of the Bactrocera （Diptera： Tephritidae） are one of the major economically important insects in Asia. So far, there are at least seven species found in Chongqing, China. By using mitochondrial 16s rDNA sequences, the phylogenetic relationships among seven Bactrocera species, Bactrocera cucurbitae （Coquillett）, B. tau （Walker）, B. diaphora （Hendel）, B. caudata （Fabricius）, B. scutellata （Hendel）, B. dorsalis （Hendel）, and B. minax （Enderlein） were investigated. Nucleotide diversity within species ranged from 0.3% to 10.9%. According to the result, B. cucurbitae （Coquillett）, B. tau （Walker）, B. diaphora （Hendel）, and B. caudata （Fabricius） have no enough sites to be distinguished among the other species in the 347bp nucleotide sequences of the 16s rDNA gene. At the same time, excluding B. scutellata （Hendel） and B. minax （Enderlein）, the other species recognition sites are not only too little but also discontinuous. Phylogenetic trees calculated from both maximum parsimony and neighbor-joining phylogenetic analysis methods showed that B. cucurbitae and B. tau were closely related, B. diaphora （Hendel） and B. caudata （Fabricius） also had a close relationship. B. minax （Enderlein） has a furthest relationship from the other 6 species. From the results, we can infer that the our data supports previous classification of Bactrocera based on morphological characters in other words, but the Bactrocera subgenera, Zeugodacus is polyphyletic.

关键词： Bactrocera spp 16s rDNA mitochondrial DNA molecular phylogeny

Correspondence:Unified characterization of hydro-mechanical properties of soil-bentonite mixtures exposed to pore-fluid salinity

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第3期22卷 188-194页

作者： Xin LIU Wen-zhe ZHANG Xiao WEI Heng-xing lan Schoolof Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China Research Center of Coastal and Urban Geotechnical Engineering Zhejiang UniversityHangzhou 310058China State Key Laboratory of Resources and Environmental Information System(LREIS) Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

1 Introduction Knowledge on the impact of pore-fluid salinity,characterized by the changes of pH,ionic concentration,material composition,and other factors,on geotechnical engineering applications involving hydro-chem... 详细信息

关键词： salinity fluid soil

Isolation and Crystal Structure of Horminone

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Chinese Journal of Structural Chemistry 2000年第2期19卷 122-125页

作者： CHEN Xiao * LIAO Ren An WENG Lin Hong XIE Qing lan(Institute and State Key Laboratory of Elemento Organic Chemistry, Nankai University, Tianjin, 300071) DENG Feng Jie (Department of Chemistry, Nanchang University, Nanchang 330047) 南开大学元素有机化学国家重点实验室天津 3 0 0 0 71 南昌大学江西南昌 33 0 0 47

The horminone (C 20 H 28 O 4, M r =332.85) was first isolated from the leaves of Rabdosia Serra (Maxim) Hara and its crystal structure was determined by X ray diffraction method. Horminone is orthorhombic with space group P2 1P2 1P2 1, a=7.7186(7), b=9.5506(9), c=24.227(2) , V=1785.9(3)  3, Z=4, D c =1.236 g/cm 3, λ=0.71073 , μ (Mo Kα )=0.085mm -1 , F (000)=720. The structure was refined to R=0.0369, wR= 0.0978 for 2446 reflections with I>2σ(I ). X ray diffraction analysis reveals that there are three six membered rings in the title molecule. Ring A is in the chair conformation, ring C has the structure of quinone and there are two intermolecular hydrogen bonds between two molecules.

关键词： crystal structure rabdosia serra (Maxim) hara abietane quinones

Pharmacological effects of Rg1 in neuropsychopharmacology

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中国药理学与毒理学杂志 2019年第10期 842-843页

作者： GAO Yan CHU Shi-feng ZHANG Zhao ZHANG lan CHEN Nai-hong State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaNeuroscience Center Chinese Academy of Medical Sciences and Peking Union Medical College Department of Pharmacy Xuanwu Hospital of Capital Medical University Hunan University of Chinese Medicine

Panax Ginseng has been used for thousands of years in traditional Chinese medicine(TCM) as a tonic to improver stamina and vitality. Ginsenoside Rg1(Rg1), a saponin extracted from Panax ginseng, is considered one of the most potent pharmacological candidates among TCM. In various diseases related to nervous system, Rg1 has shown excellent pharmacological activities.(1) Stroke: Rg1 has been well documented to be effective against ischemic/reperfusion(I/R) neuronal injury. A systematic review and meta-analysis revealed a marked efficacy of Rg1 in experimental acute ischemic stroke, as manifested by its ability to reduce infract volume and improve neurological score. The protective effects of Rg1 were abolished by injecting of AAV-HIF-mi R-144-sh RNA into the predicted ischemic penumbra.(2) Depression: in addition, Rg1 showed antidepressive effects in chronic unpredictable mild stress(CUMS) model of depression and in gonadectomized(GDX) model of neuroendocrine disturbance. Rg1 displayed antidepressant activity through the modulation of HPA and HPG axis, markedly alleviated depression-like behavior in rats. Long-term Rg1 treatment of CUS-exposed rats also significantly prevented the decrease in dye diffusion and improved the ultrastructure of astrocyte gap junctions in the ***1 upregulated Cx43 expression in PFC reduced by CUS exposure, indicating beneficial effects on the functional activity of gap junction channels in the brain.(3)Parkinson disease(PD): oral treatment with Rg1 significantly attenuated high MPTP-induced mortality, behavior defects, loss of dopamine neurons and abnormal unltrastructure changes in SNpc. It regulated MPTP-induced reactive astrocytes and microglia and decreased the release of cytokines such as TNF-α and IL-1β in ***1 also alleviated the unusual MPTP-induced increase in oligomeric, phosphorylated and disease-related α-synuclein in SNpc.(4) Alzheimer disease(AD): okadaic acid(OKA) intracerebroventricular injection induced memory impai

关键词： ginsenoside Rg1 neuropsychopharmacology multiple targets

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活性炭孔结构调节:理论、方法与实践

新型炭材料 2005年第2期20卷 183-190页

作者：解强张香兰李兰廷金雷中国矿业大学(北京)化学与环境工程学院北京100083

活性炭的吸附性能主要由其孔结构和表面官能团决定,尤其是孔结构对活性炭的性能有时甚至有决定性的影响。因此,根据用途与应用领域对吸附剂性能的要求定向制备具有特定孔结构的活性炭的方法具有重大的意义。通过对活性炭制备过程中孔结... 详细信息

活性炭的吸附性能主要由其孔结构和表面官能团决定,尤其是孔结构对活性炭的性能有时甚至有决定性的影响。因此,根据用途与应用领域对吸附剂性能的要求定向制备具有特定孔结构的活性炭的方法具有重大的意义。通过对活性炭制备过程中孔结构调控方法研究状况的评介,以期对深入理解孔结构对活性炭的意义、阐释孔结构调控机理和方法有所帮助,进而指导制备具有要求结构和性能活性炭的生产实践。

关键词：活性炭孔结构定向制备

DEC1 deficiency protects against bone loss induced by ovariectomy by inhibiting inflammation

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Journal of Biomedical Research 2024年第6期38卷 613-627页

作者： lan Lin Zhiyi Qiang Kaiao Chen Ying Huo Wei Liu Jian Yang Department of Pharmacology Nanjing Medical UniversityNanjingJiangsu 211166China

Studies have shown that differentiated embryo-chondrocyte expressed gene 1(DEC1)promotes osteoblast *** investigate the role of DEC1 in postmenopausal osteoporosis,we used the two genotypes of mice(Dec1+/+and Dec1-/-)to establish an ovariectomy model and found that the bone loss was significantly lower in Dec1-/-ovariectomy mice than in Dec1+/+ovariectomy *** expression levels of RUNX2 and OSX were significantly increased in Dec1-/-ovariectomy mice,compared with Dec1+/+ovariectomy mice;however,the expression levels of NFATc1,c-Fos,CTSK,and RANKL/OPG ratio were significantly decreased in Dec1-/-ovariectomy mice,compared with those in Dec1+/+ovariectomy ***,DEC1 deficiency also suppressed the expression levels of IL-6 and IL-1β.Further results showed that the mRNA expression levels of Runx2,Osx,and Alp were significantly increased in bone marrow mesenchymal stem cells of Dec1-/-ovariectomy mice,compared with those of Dec1+/+ovariectomy ***,the mRNA levels of Il1b,Il6,Tnfa,and Ifng were significantly increased in bone marrow-derived macrophages(BMMs)of Dec1+/+ovariectomy mice,compared with those of Dec1+/+sham mice,but not in Dec1-/-ovariectomy BMMs,when compared with those in Dec1-/-sham ***,the expression levels of p-IκBαand p-P65 were significantly increased in Dec1+/+ovariectomy BMMs,compared with those in Dec1+/+sham BMMs,but did not increase in Dec1-/-ovariectomy BMMs,compared with those in Dec1-/-sham *** together,DEC1 deficiency inhibited the NF-κB pathway induced by ovariectomy,thereby decreasing cytokines and subsequently inhibiting the decrease of osteo-genesis and the increase of osteoclastogenesis caused by *** findings may provide a novel under-standing of postmenopausal osteoporosis development,and offer potential avenues for the disease intervention.

关键词： DEC1 postmenopausal osteoporosis estrogen osteoblasts osteoclasts

SiC_p含量和尺寸对Al基复合材料摩擦学特性的影响

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中国有色金属学报 2005年第3期15卷 458-462页

作者：戈晓岚许晓静蔡兰陈康敏居志兰江苏大学机械工程学院镇江212013

通过分析SiCp/Al基复合材料中第二相SiCp 的含量、分布和尺寸对其性能的影响, 深入地研究了微米、亚微米SiCp/Al复合材料的摩擦磨损特性, 尤其是SiCp/Al复合材料磨损亚表层特性的影响。研究结果表明: 复合材料的磨损是粘着磨损、微切削... 详细信息

通过分析SiCp/Al基复合材料中第二相SiCp 的含量、分布和尺寸对其性能的影响, 深入地研究了微米、亚微米SiCp/Al复合材料的摩擦磨损特性, 尤其是SiCp/Al复合材料磨损亚表层特性的影响。研究结果表明: 复合材料的磨损是粘着磨损、微切削和剥层的共同作用, SiCp 对材料粘着磨损有一定的抑制作用, 且随着SiCp 粒度和含量的增大, SiCp/Al基复合材料的耐磨性也随之增加; 由于 SiCp 承担了部分载荷和表层存在着机械混合层,因此复合材料具有比其基体金属更高的耐磨性。

关键词： SiCp/Al复合材料摩擦表面亚表层机械混合层

Terahertz wide range phase manipulation with super-resolution precision by near-field nonlinear coupling of a digitally coding needle meta-chip

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Photonics Research 2024年第9期12卷 1868-1876页

作者： HUAJIE LIANG HONGXIN ZENG TIANCHI ZHOU HANYU ZHAO SHAOKANG GU LIN ZOU TAO JIANG lan WANG FENG lan SHIXIONG LIANG ZHIHONG FENG ZIQIANG YANG YAXIN ZHANG Huzhou Key Laboratory of Terahertz Integrated Circuits and Systems Yangtze Delta Region Institute(Huzhou)University of Electronic Science and Technology of ChinaHuzhou 313001China Sichuan Engineering Center of Integrated Optoelectronic&Radio Meta-chips School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731China National Key Laboratory of Solid-State Microwave Device and Circuit Hebei Semiconductor Research InstituteShijiazhuang 050051China Zhangjiang Laboratory Shanghai 201204China

Achieving ultra-precise wide-range terahertz(THz)phase modulation has been a long-standing challenge due to the short wavelength and sensitive phase of THz *** paper proposes a new ultra-high precision phase control method employing a digitally coding needle meta-chip embedded in a *** needle tips can effectively couple THz waves via the charge aggregation *** controlling the Schottky diodes with coding voltages,the charge on each meta-structure part can be tuned to form strong or weak resonances,producing phase ***,the massive charge accumulation and the sub-λ∕10 distance between needle tips lead to near-field coupling among multiple ***,modulation of the charge at each tip by multichannel coding voltages enables combined resonance tuning of THz waves,yielding a nonlinear phase ***,a meta-chip containing 8 needle meta-structure units is demonstrated,which breaks through the precision limitation of independent units and realizes super-resolution precision phase modulation similar to super-resolution *** the 213–227 GHz band,we achieve a phase shift exceeding 180°with 11.25°accuracy,and a phase shift of over 170°with an accuracy of 3°.This super-resolution phase modulation strategy provides a new idea for future highprecision applications of THz integrated systems.

关键词： tuning phase resolution