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气动执行器系统节能研究概述

内燃机与配件 2024年第6期 146-148页

作者：李奉奇中铁十二局集团第一工程有限公司陕西西安710038 中铁十二局集团第一工程有限公司西安市博士后创新基地陕西西安710038

气动系统具有简单可靠、传递介质易获取等优势,应用范围不断扩展,但其能量利用率最低仅有20%,限制气动技术进一步发展。本文总结当前国内外气动系统节能技术进展,发现合理利用排气可显著提升节能效率,并将排气利用分类为直接利用排气、... 详细信息

气动系统具有简单可靠、传递介质易获取等优势,应用范围不断扩展,但其能量利用率最低仅有20%,限制气动技术进一步发展。本文总结当前国内外气动系统节能技术进展,发现合理利用排气可显著提升节能效率,并将排气利用分类为直接利用排气、回收利用排气、转化能量形式三种节能方式,分析了不同节能方式的优势,为后续气动系统节能研究提供理论依据。

关键词：节能排气利用回收利用能量转换

Genetic and Association Mapping Study of English Grain Aphid Resistance and Tolerance in Bread Wheat Germplasm

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Journal of Integrative Agriculture 2014年第1期13卷 40-53页

作者： li feng-qi PENG Jun-hua Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of Sciences University of Chinese Academy of Sciences Department of Soil and Crop Sciences Colorado State University

English grain aphid （EGA） is a destructive insect pest of wheat. To identify the loci associated with EGA resistance and tolerance, 70 bread wheat accessions mainly from central Asia were evaluated for EGA resistance and tolerance traits at two locations, and genotyped with 51 SSR markers. Totally, three accessions showed high or moderate levels resistance and 17 genotypes displayed highly or moderately tolerate to EGA. Genetic diversity of these lines was investigated also. After 97 SSR loci which evenly covered all wheat chromosomes were scanned for association, four SSR loci were significantly associated with EGA resistance and four with EGA tolerance. After association analysis was conducted with dynamic aphid densities, we found four loci Xgwm192b, Xgwm391, Xbarc98, and Xgwm613b were detected continuously at different growing stages of wheat. In addition, the loci of EGA resistance/tolerance and Russian wheat aphid resistance were compared. The results generated in this study would be helpful for utilization of the EGA resistance/tolerance germplasm, and for development of mapping populations in EGA resistance breeding programs.

关键词： English grain aphid resistance tolerance association mapping Triticum aestivum

基于系统动力学的平原河网型灌区多尺度下灌溉用水量计算方法研究

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中国农村水利水电 2024年第1期 25-29,36页

作者：李其峰陈彩明李冬晓蔡晨凯王士武浙江省水利河口研究院(浙江省海洋规划设计研究院) 浙江杭州310020 中国电建集团华东勘测设计研究院有限公司浙江杭州311122

以嘉兴市长水塘灌区为研究对象,建立基于系统动力学的灌区水循环过程模拟模型,并引入灌片灌溉水回归系数,应用于灌区灌溉回归水重复利用量模拟分析以及多尺度下灌溉用水量计算。结果表明:通过对模型的率定与验证,模拟得到典型泵站模拟... 详细信息

以嘉兴市长水塘灌区为研究对象,建立基于系统动力学的灌区水循环过程模拟模型,并引入灌片灌溉水回归系数,应用于灌区灌溉回归水重复利用量模拟分析以及多尺度下灌溉用水量计算。结果表明:通过对模型的率定与验证,模拟得到典型泵站模拟水量与实测值基本吻合,相对差绝对值均在15%以内,模拟得到的灌区河网水位变化趋势与实测过程基本一致。模型能够较好的反映灌区水量转化过程,能够为灌区灌溉用水量统计工作提供支撑。

关键词：灌溉用水量回归水重复利用系统动力学平原河网型灌区

Microstructural evolution and mechanical properties of aging high nitrogen austenitic stainless steels

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 729-736页

作者： Zhou-hua Jiang Zu-rui Zhang Hua-bing li Zhen li qi-feng Ma School of Materials and Metallurgy Northeastern University Shenyang 110819 China

The microstructural evolution of 18Crl 8Mn2Mo0.77N high nitrogen austenitic stainless steel in aging treatment was investigated by optical microscopy （OM）, scanning electron microscopy （SEM）, and transmission electron microscopy （TEM）. The results show that hexagonal intergranular and cellular Cr2N with a=0.478 nm and c=0.444 nm and body-centered cubic intermetaUic X phase with a=0.892 nm precipitate gradually in the isothermal aging treatment. The matrix nitrogen depletion due to the intergranular Cr2N precipitation induces the decay of Vickers hardness, and the formation of cellular Cr2N and X phase causes the increase in the values. The impact toughness presents a monotonic decrease and SEM morphologies show the leading brittle intergranular fracture. The tensile strength and elongation deteriorate obviously except for the sample aged for 1 h in yield strength. Stress concentration occurs when the matrix dislocations pile up at the pre- cipitation and matrix interfaces, and the interracial dislocations may become precursors to the misfit dislocations, which can form small cleavage steps and accelerate the formation of cracks.

关键词： microstructural evolution aging mechanical properties austenitic stainless steel secondary phase

PERFORMANCE ANALYSIS AND SIMULATION OF VARIOUS BURST TIME PLAN GENERATION METHODS IN BROADBAND SATELliTE MULTIMEDIA SYSTEM

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Journal of Electronics(China) 2011年第2期28卷 187-197页

作者： feng Shaodong li Guangxia feng qi Institute of Communication Engineering PLA University of Science and Technology Nanjing 210007 China

The Burst Time Plan(BTP) generation is the key for resource allocation in Broadband Satellite Multimedia(BSM) *** main purpose of this paper is to minimize the system response time to users' request caused by BTP generation as well as maintain the Quality of Service(QoS) and improve the channel utilization *** the BTP is generated periodically in order to simplify the implementation of the resource allocation *** on the analysis we find that Periodical BTP Generation(P-BTPG) method cannot guarantee the delay performance,channel utilization efficiency and QoS simultaneously,especially when the capacity requests arrived *** Optimized BTP Generation(O-BTPG) method is given based on the optimal scheduling period and scheduling latency without considering the signaling ***,a novel Asynchronous BTP Generation(A-BTPG) method is proposed which is invoked according to users' requests.A BSM system application scenario is *** results show that A-BTPG is a trade-off between the performance and signaling overhead which can improve the system performance insensitive to the traffic *** method can be used in the ATM onboard switching satellite system and further more can be expended to Digital Video Broadcasting-Return Channel Satellite(DVB-RCS) system or IP onboard routing BSM system in the future.

关键词： Broadband Satellite Multimedia(BSM) Burst Time Plan(BTP) Resource allocation Multiple access Digital Video Broadcasting-Return Channel via Satellite(DVB-RCS)

POLY(MALEIC ANHYDRIDE-CO-ACRYliC ACID)/POLY(ETHYLENE GLYCOL)HYDROGELS WITH pH- AND IONIC-STRENGTH-RESPONSES

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Chinese Journal of Polymer Science 2010年第6期28卷 951-959页

作者： Meng Yang Bo-tian liu Ge Gao Xiao-li liu feng-qi liu College of Chemistry and Macdiarmid Laboratory Jilin University Changchun 130012 China

Poly（maleic anhydride-coacrylic acid）,P（MA-AA）,was synthesized by the free-radical copolymerization of maleic anhydride with acrylic acid,and fast responsive pH-sensitive poly（maleic anhydride-co-acrylic acid）/polyethylene glycol,P（MA-AA）/PEG,hydrogels were prepared using PEG as macromolecular cross-linking ***-IR and ~1H-NMR spectrometry were applied to characterize the structure of P（MA-AA）.The influences of pH and ionic strength on the swelling behavior of P（MA-AA）/PEG hydrogels and the swelling-deswelling changes along with the repeated changes between acid and alkali conditions were *** results showed that there was a hundredfold difference in the swelling ratios between the conditions of acid and alkali,and the swelling capability could not be weakened after multiple swelling-deswelling *** results of swelling kinetics demonstrated that the response rate of P（MA-AA）/PEG hydrogels was very fast,because the swelling transition points always occurred at 10 *** pH-responsive hydrogels reported here might be a smart material for potentially applications in many areas,including biosensors,drug-delivery devices and tissue engineering.

关键词： pH-response P(MA-AA) Macromolecular cross-linking agent External cross-linking

Functional characterization of(E)-β-caryophyllene synthase from lima bean and its up-regulation by spider mites and alamethicin

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Journal of Integrative Agriculture 2017年第10期16卷 2231-2238页

作者： li feng-qi FU Ning-ning ZHOU Jing-jiang WANG Gui-rong Institute of Plant and Environment Protection Beijing Academy of Agriculture and Forestry Sciences Institute of Plant Protection Chinese Academy of Agricultural Sciences Department of Biological Chemistry and Crop Protect Rothamsted Research

（E）-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of （E）-β-caryophyllene synthase in lima bean （Phaseolus lunatus）. Here, we report a new full-length cDNA （PICAHS） encoding （E）-β-caryophyllene synthase, a possible key enzyme of plant defence. The cDNA of PICAHS contains an open reading frame of 1 761 bp, encoding a protein of 586 amino acids with a predicted mass of 67.95 kDa. The deduced amino acid sequence shows 52% identity with sesquiterpene synthase MtCAHS of Med- icago truncatula. Based on phylogenetic analysis, PICAHS is classified as the terpene synthases （TPS）-a subfamily. The recombinant enzyme, expressed in Escherichia coil, catalysed the formation of a major product （E）-β-caryophyllene （82%） and a minor product a-humulene （18%） from farnesyl dJphosphate. Real-time quantitative PCR （qRT-PCR） analysis found that the PICAHS transcript was significantly up-regulated in leaves after treatment with spider mites and alamethicin （ALA）, suggesting its ecological function in plant defence.

关键词： plant defence terpene synthases (E)--caryophyllene lima bean

特发性身材矮小患儿肠道菌群改变及其与体格发育的关系分析

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罕少疾病杂志 2024年第2期31卷 98-99,105页

作者：郭静李凤启王彬彬王芳周口市妇幼保健院(周口市儿科研究所)儿科河南周口466000

目的观察特发性身材矮小(ISS)患儿肠道菌群变化,并分析其与患儿体格发育的关系。方法选取本院2020年5月至2022年5月收治的106例ISS患儿设为ISS组,另同期选取106例在本院行健康体检的正常儿童作为对照组,检测两组体格发育指标[包括身高... 详细信息

目的观察特发性身材矮小(ISS)患儿肠道菌群变化,并分析其与患儿体格发育的关系。方法选取本院2020年5月至2022年5月收治的106例ISS患儿设为ISS组,另同期选取106例在本院行健康体检的正常儿童作为对照组,检测两组体格发育指标[包括身高、体重、身体质量指数(BMI)、骨龄],并收集粪便样本检测肠道菌群,另采用Pearson法分析ISS患儿肠道菌群与体格发育指标的相关性。结果ISS组身高、体重、BMI、骨龄均低于对照组(P0.05);ISS组酵母菌、肠球菌、产气荚膜梭菌水平比较无明显差异(P>0.05),ISS组大肠杆菌水平高于对照组,乳酸杆菌、双歧杆菌、拟杆菌水平低于对照组(P<0.05);ISS患儿乳酸杆菌、双歧杆菌水平与身高、体重、BMI、骨龄呈正相关(P<0.05),拟杆菌水平与身高、体重、BMI呈正相关(P<0.05)。结论ISS患儿乳酸杆菌、双歧杆菌、拟杆菌等厌氧菌水平明显下降,肠杆菌、乳酸杆菌、双歧杆菌、拟杆菌水平与体格发育指标具有相关性,可能是ISS发病的原因之一。

关键词：儿童特发性身材矮小肠道菌群体格发育

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输尿管镜碎石术后感染病原菌与危险因素及感染相关指标水平的预测价值

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中华医院感染学杂志 2024年第8期34卷 1191-1195页

作者：陈怀安刘硕王哲苏军涛张潮苗文隆李凤岐河北北方学院附属第一医院泌尿外科河北张家口075000

目的探讨输尿管镜碎石术后感染的病原学特点、相关因素及肝素结合蛋白(HBP)、β2-微球蛋白(β2-MG)、C-反应蛋白(CRP)水平的预测价值。方法回顾性分析256例2020年2月-2023年2月河北北方学院附属第一医院收治的行输尿管镜碎石术患者临床... 详细信息

目的探讨输尿管镜碎石术后感染的病原学特点、相关因素及肝素结合蛋白(HBP)、β2-微球蛋白(β2-MG)、C-反应蛋白(CRP)水平的预测价值。方法回顾性分析256例2020年2月-2023年2月河北北方学院附属第一医院收治的行输尿管镜碎石术患者临床资料,根据术后感染分为感染组和未感染组(52例/204例)。统计输尿管镜碎石术后感染的病原菌分布特点;采用Logistic分析法分析输尿管镜碎石术后感染的相关因素;采用酶联免疫吸附实验、乳胶免疫比浊法、化学发光法分别检测HBP、β2-MG、CRP水平;比较两组HBP、β2-MG、CRP水平;采用受试者工作特征(ROC)曲线分析HBP、β2-MG、CRP对输尿管镜碎石术后感染的诊断价值。结果输尿管镜碎石术后感染发生率为20.31%(52/256),革兰阴性菌为主;Logistic回归分析结果显示,输尿管镜碎石术后感染的相关因素包括年龄、手术时间、有糖尿病史、导管留置时间(P<0.05);感染组β2-MG、CRP水平较未感染组高(P<0.05),HBP≥0.05ng/ml患者占比较未感染组高(P<0.05);HBP、β2-MG、CRP联合检测诊断输尿管镜碎石术后感染的AUC高于各项单独检测(P<0.05),敏感度和特异度为75.00%,93.60%。结论输尿管镜碎石术后感染发生率较高,多为革兰阴性菌感染,且与患者年龄、手术时间、糖尿病史、导管留置时间相关。输尿管镜碎石术后感染HBP、β2-MG、CRP呈高表达;HBP、β2-MG、CRP联合检测有助于诊断输尿管镜碎石术后感染。

关键词：输尿管结石输尿管镜碎石术感染病原菌危险因素肝素结合蛋白 β2-微球蛋白 C-反应蛋白