检索结果-南通市图书馆

Disordered Fragments of Chemical Structures Based on Single-crystal X-ray Diffraction

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2020年第4期39卷 698-708页

作者： ZHANG Jun MA xiao-Fan xuan xiao-Peng School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan 453007China Department of Chemistry The Hong Kong University of Science&TechnologyHong KongChina

For the reported chemical structures,the disordered fragments of the structure acting as hosts and guests are common and unmanageable for *** to analyze and treat such disordered assemblies is an important task for *** is often difficult for some researchers to refine the disordered structures,even to mechanically justify the refined consequence in the absence of ***,some examples of disorder refinements selected from the literature,including the disordered assemblies of nitrate,perchlorate,alkyl,aromatic assemblies,and guest solvent molecules,are summarized and discussed to provide practical advice for investigating the disorders for crystallographic researchers and *** refinement approach for these disordered assemblies is also discussed in detail,which is helpful for crystallographers.

关键词： single-crystal X-ray diffraction crystal-structure refinement disorder disordered assemblies

异质钛合金线性摩擦焊接接头拉伸过程数值模拟研究

在线全文

学校读者我要写书评

暂无评论

热加工工艺 2024年第7期53卷 37-40,46页

作者：肖旋秦鼎强毛悦王心成李菊傅莉西北工业大学凝固技术国家重点实验室陕西西安710072 中国航空制造技术研究院航空焊接与连接技术航空科技重点实验室北京100024

基于线性摩擦焊(LFW)接头的组织特征及其材料性能,探索接头分区建模方法,采用有限元技术实现了TC11/TC17异质钛合金LFW接头拉伸过程的数值模拟,揭示了接头拉伸过程中不同焊接区的应力应变演变规律,预测了接头的力学性能和断裂位置。结... 详细信息

基于线性摩擦焊(LFW)接头的组织特征及其材料性能,探索接头分区建模方法,采用有限元技术实现了TC11/TC17异质钛合金LFW接头拉伸过程的数值模拟,揭示了接头拉伸过程中不同焊接区的应力应变演变规律,预测了接头的力学性能和断裂位置。结果表明,在2000 N均布的拉伸加载条件下,可计算预测出TC11/TC17异质钛合金LFW接头的屈服强度、抗拉强度分别为1045、1082 MPa,与实际测量值的误差小于2.5%。拉伸过程中接头在焊核区边缘存在应力峰值。在TC11母材区距焊缝中心24.2 mm位置存在应力和应变集中,应力集中区的应力值在1057 MPa以上,应变最高可达18.52%。该位置出现了颈缩现象,表明TC11/TC17异质钛合金LFW接头在该位置发生断裂。

关键词： TC11/TC17钛合金线性摩擦焊接力学性能纳米压痕

普拉洛芬滴眼液联合高浓度玻璃酸钠滴眼液治疗老年干眼症的疗效分析

在线全文

学校读者我要写书评

暂无评论

中国实用医药 2024年第9期19卷 109-112页

作者：窦莹温小萱刘伟吉林省一汽总医院 130011

目的探讨普拉洛芬滴眼液联合高浓度玻璃酸钠滴眼液治疗老年干眼症的疗效。方法将96例老年单眼干眼症患者随机分为对照组及观察组,每组48例。对照组使用高浓度(0.3%)玻璃酸钠滴眼液治疗,观察组在对照组基础上使用普拉洛芬滴眼液治疗。比... 详细信息

目的探讨普拉洛芬滴眼液联合高浓度玻璃酸钠滴眼液治疗老年干眼症的疗效。方法将96例老年单眼干眼症患者随机分为对照组及观察组,每组48例。对照组使用高浓度(0.3%)玻璃酸钠滴眼液治疗,观察组在对照组基础上使用普拉洛芬滴眼液治疗。比较两组患者的临床疗效,治疗前后的各项干眼指标[泪膜破裂时间(BUT)、基础泪液分泌试验(SⅠt)、角膜荧光素染色(FL)评分]、泪液炎性因子[转化生长因子-β1(TGF-β1)、白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)]水平及症状(干涩、烧灼感、畏光、眼痛)评分。结果观察组治疗总有效率为95.83%,明显高于对照组的75.00%(P<0.05)。观察组治疗后BUT(5.70±0.69)s、SⅠt(8.50±1.14)mm/5 min均长于对照组的(4.82±0.83)s、(7.26±1.09)mm/5 min,FL评分(3.12±0.75)分低于对照组的(4.31±0.97)分(P<0.05)。观察组治疗后泪液中TGF-β1(79.25±14.91)pg/ml高于对照组的(65.07±12.68)pg/ml,IL-6(252.71±70.48)pg/ml、IL-1β(75.32±19.57)pg/ml低于对照组的(351.63±79.45)、(99.73±20.94)pg/ml(P<0.05)。观察组治疗后干涩、烧灼感、畏光、眼痛症状评分分别为(0.83±0.19)、(0.78±0.14)、(0.84±0.13)、(0.92±0.15)分,明显低于对照组的(1.48±0.22)、(1.41±0.23)、(1.45±0.21)、(1.49±0.24)分(P<0.05)。结论普拉洛芬滴眼液联合高浓度玻璃酸钠滴眼液治疗老年干眼症的疗效显著,能有效湿润眼表,延长BUT,改善泪液质量,缓解临床症状。

关键词：老年干眼症普拉洛芬滴眼液高浓度玻璃酸钠滴眼液疗效

Production of Transgenic Anliucheng Sweet Orange(Citrus sinensis Osbeck) with Xa21 Gene for Potential Canker Resistance

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2014年第11期13卷 2370-2377页

作者： LI Ding-li xiao xuan GUO Wen-wu Key Laboratory of Horticultural Plant Biology Ministry of Education/College of Horticulture & Forestry Sciences Huazhong Agricultural University College of Life and Environmental Sciences Gannan Normal University

Citrus canker, an epidemic quarantine disease caused by Xanthomonas axonopodis pv. citri, has brought a great damage in citrus production worldwide. Herein, a rice PRR （pattern recognition receptor） gene Xa21 together with GUS reporter gene and hygromycin phosphotransferase gene （HPT） was introduced into Anliucheng sweet orange （Citrus sinensis Osbeck） via Agrobacterium-mediated transformation of embryogenic callus. The transgenic calluses were screened on MT basal medium containing hygromycin （HYG） and detected by histochemical GUS staining. The transgenic plantlets were recovered through somatic embryogenesis pathway. The regenerated plantlets were accustomed to and maintained in the greenhouse. The transgene integration of recovered plantlets was identiifed by PCR and Southern blot hybridization. It showed that all the transgenic plantlets tested had undergone single copy integration, the expression of Xa21 in eight different transgenic lines detected by qRT-PCR can be divided into three grades, high for T5 and T6, middle for T4 and low for the rest. The tolerance to citrus canker disease of the three recovered transgenic lines T2, T4 and T6 was assessed by in vitro pin-puncture inoculation. The results showed that all the three transgenic lines conferred improved resistance to citrus canker bacterium infection and the T4 transgenic line displayed the highest resistance. The mechanism and feasibility of rice Xa21 in triggering innate immunity in citrus was brielfy discussed.

关键词： citrus canker Xa21 sweet orange pattern recognition receptors (PRRs)

在线全文

学校读者我要写书评

暂无评论

水电工程生态效益评价指标体系研究

长江科学院院报 2024年第9期41卷 8-18页

作者：王鹏翔姜晓萱徐杨王冬霍军军周涛中国长江三峡集团有限公司科学技术研究院北京100038 长江科学院水资源综合利用研究所武汉430010 长江科学院流域水资源与生态环境科学湖北省重点实验室武汉430010 长江水利委员会长江经济带保护与发展战略研究中心武汉430010 中国长江电力股份有限公司武汉443002

针对水电工程生态效益内涵模糊、生态效益价值难以量化等问题,以三峡工程为例,梳理现有生态效益研究,界定了水电工程生态效益内涵。基于河流生态系统服务功能,从供给服务功能、支持服务功能、调节服务功能、文化服务功能4个方面提出水... 详细信息

针对水电工程生态效益内涵模糊、生态效益价值难以量化等问题,以三峡工程为例,梳理现有生态效益研究,界定了水电工程生态效益内涵。基于河流生态系统服务功能,从供给服务功能、支持服务功能、调节服务功能、文化服务功能4个方面提出水电工程生态效益评价框架,构建水电工程生态效益评价指标体系。收集相关数据,针对不同效益指标进行定量分析,采取影子价格法等方法将其转换成可量化的经济价值数据。结果表明,三峡工程供给服务功能效益价值为1 047.83亿元,支持服务功能效益价值为200.74亿元,调节服务功能效益价值为833.8亿元,文化服务功能效益价值为195.56亿元,共计2 277.93亿元。研究结果可为长江流域建立生态产品价值实现机制,完善市场化、多元化生态补偿,提供技术支持。

关键词：生态服务功能价值评估效益评价三峡工程指标体系

Anodic-Cathodic Electrocatalytic Degradation of Phenol with Oxygen Sparged in the Presence of Iron(Ⅱ)

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

Chemical Research in Chinese Universities 2002年第3期18卷 262-266页

作者： ZHOU Ming hua WU Zu cheng xuan xiao dong Department of Environmental Engineering Zhejiang UniversityHangzhou 310027P.R.China

Under oxygen sparged, the synergetic effects of both anodic cathodic electrocatalysis(ACE) and ferrous ion catalyzed anodic cathodic electrocatalysis(FeACE) on phenol degradation were observed in an undivided cell composed of a β PbO 2 anode modified with fluorine resin and a nickel chromium titanium alloy net cathode. Oxygen sparging rate, ferrous concentration, and current significantly affect phenol destruction. The phenol was removed by 10%-13% increasingly under FeACE vs . ACE, and by 12%-15% under ACE vs . anodic electrocatalysis(AE). The phenol destruction was due to the formation of hydroxyl oxidant on the surface of lead oxide at the anode and the reduction of oxygen at the cathode.

关键词： Anodic cathodic electrocatalysis Phenol degradation Advanced oxidation process

西氏熊蜂线粒体基因组结构特征及系统发育分析

在线全文

学校读者我要写书评

暂无评论

草地学报 2024年第8期32卷 2408-2418页

作者：马晓璇梁程博刘道鑫孙国闫京艳青海大学农牧学院青海西宁810016

本研究利用二代测序技术对西氏熊蜂(Bombus sichelii)的线粒体基因组进行了测序、组装和注释,并对其线粒体基因组的组成、结构特征、基因重排及系统发育等方面进行了生物信息学分析。结果表明:西氏熊蜂线粒体基因组长度为15711 bp,包含1... 详细信息

本研究利用二代测序技术对西氏熊蜂(Bombus sichelii)的线粒体基因组进行了测序、组装和注释,并对其线粒体基因组的组成、结构特征、基因重排及系统发育等方面进行了生物信息学分析。结果表明:西氏熊蜂线粒体基因组长度为15711 bp,包含13个蛋白编码基因、22个tRNA基因和2个rRNA基因;线粒体基因组全序列、蛋白编码基因的串联序列、tRNA串联序列、rRNA串联序列的A+T含量均大于80%,表现出明显的碱基偏倚;13个蛋白编码基因的起始密码子均为ATN,终止密码子为TAA,TAG或T--。tRNA二级结构预测发现,trnS 1与其他昆虫具有相同的特征,即缺少DHU臂和DHU环,其余21个tRNA均能形成典型的三叶草结构;系统发育进化分析结果高度支持西氏熊蜂与火红熊蜂(***)隶属于黑熊蜂亚属(Melanobombus)。本研究首次获得西氏熊蜂线粒体基因组序列,初步鉴定了其线粒体基因组的特征,为进一步对熊蜂线粒体基因组学和系统发育关系的研究奠定了基础。

关键词：西氏熊蜂线粒体基因组生物信息学系统发育分析

维普期刊数据库博看期刊

Non-line-of-sight error mitigating algorithm based on scattering models via multi-antenna system

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 18-22页

作者： ZHU xiao-xuan SHI Ming-yang ZHANG Jing TAO xiao-feng Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Wireless Technology Innovation Institute (WTI) Beijing 100876 China

In urban environment with serious blocking of direct paths, the non-line-of-sight （NLOS） propagation influences the location estimation accuracy. In this article, a novel algorithm is developed, which can mitigate the NLOS errors in location estimation significantly. Utilizing multiantenna array, the information of scatterers that cause the NLOS propagation is obtained. Then, we combine the information with TOA/TDOA based location algorithm to estimate the location of mobile station （MS）. The simulation results show that our method can mitigate NLOS errors and enhance the location accuracy greatly.

关键词： multi-antenna location algorithm NLOS time of arrival (TOA)

DR5 is a Suitable System for Studying the Auxin Response in the Poncirus trifoliata-Xanthomonas axonopodis *** Interaction

在线全文

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2020年第5期6卷 277-283页

作者： xuan xiao xiaoyan Li Chunli Chen Wenwu Guo College of Life Science Gannan Normal UniversityGanzhouJiangxi 341000China Key Laboratory of Horticultural Plant Biology(Ministry of Education) College of Horticulture and Forestry SciencesHuazhong Agricultural UniversityWuhan 430070China

The local auxin distribution characteristics in the roots,stems,and leaves of stably transformed plantlets of trifoliate orange(Poncirus trifoliata)with auxin reporter system DR5::GUS-YFP were elucidated in this *** auxin response maxima could be observed in the apex of the root tip,primary phloem of the tender stem,and the margin of the young leaves according to the activity of theβ-glucuronidase(GUS)reporter gene triggered by the auxin responsive DR5 *** responses in the apex of the root tips increased when treated with synthetic auxin 1-naphthylacetic acid(NAA),but decreased when treated with the auxin polar transportation inhibitor 2,3,5-triiodobenzoic acid(TIBA).These results indicated that the DR5 reporter system worked in *** for auxin distribution and response *** orange is highly susceptible to citrus canker *** accumulation was observed visually in the invasion sites of the detached leaves inoculated with Xanthomonas axonopodis ***(Xac)by GUS staining;the upregulated expression of the YFP,GH3.1,GH3.9,and SAUR genes assessed by quantitative real-time PCR(qRT-PCR)also identified auxin accumulation in the inoculated tissues following Xac ***,these findings indicated that the plantlets of *** engineered with the auxin reporter gene provided a promising system for studying auxin responses during Xac infection.

关键词： Poncirus trifoliata DR5 auxin Xanthomonas axonopodis pv.citri