检索结果-南通市图书馆

Valence Offsets of Three Series of Alloy Heterojunctions

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1997年第10期14卷 775-777页

作者： ZHENG Jin-cheng WANG ren-zhi ZHENG Yong-mei CAI Shu-hui Department of Physics Xiamen UniversityXiamen 361005

Electron structure of three series of alloy heterojunctions(GaAs)_(x)(Ge_(2))_(1-x)/Ge,(AlAs)_(x)(Ge2)_(1-x)/Ge and Al_(x)G_(1-x)As/Ge are calculated by linear muffin-tin orbital method with atomic-sphere approximation using the average-bond-energy theory in conjunction with a cluster expansion *** results indicate the variations ofΔE_(v)(x)at heterojunctions(GeAs)_(x)(Ge2)_(1-x)/Ge and(AlAs)_(x)(Ge2)_(1-x)/Ge are nonlinear,which are very different from that of Al_(x)Ga_(1-x)As/Ge.

关键词： alloy cluster expansion

Benefits of Conservation Agriculture on Soil and Water Conservation and Its Progress in China

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

Agricultural Sciences in China 2011年第6期10卷 850-859页

作者： LI Ling-ling HUANG Gao-bao ZHANG ren-zhi Bill Bellotti Guangdi Li Kwong Yin Chan Gansu Provincial Key Laboratory of Aridland Crop Science/Faculty of Agronomy Gansu Agricultural University Lanzhou 730070 P.R. China Faculty of Resource and Environment Gansu Agricultural University Lanzhou 730070 P.R.China School of Natural Sciences University of Western Sydney NSW 1797 Australia EH Graham Centre for Agricultural Innovation （Alliance Between Investment ＆ Industry NSW and Charles Sturt University） Wagga Wagga Agricultural Institute NSW 2650 Australia Investment ＆ Industry NSW NSW 2753 Australia

Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture （CA） is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world＇s arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.

关键词： China conservation tillage crop residue mulch no-till soil and water conservation sustainability

Overexpression of IbSnRK1 enhances nitrogen uptake and carbon assimilation in transgenic sweetpotato

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2018年第2期17卷 296-305页

作者： ren zhi-tong ZHAO Hong-yuan HE Shao-zhen ZHAI Hong ZHAO Ning LIU Qing-chang Key Laboratory of Sweetpotato Biology and Biotechnology Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and Utilization Ministry of Education/China Agricultural University

Nitrogen is an important nutrient for plant development. Nitrogen and carbon metabolisms are tightly linked to physiological functions in plants. In this study, we found that the IbSnRK1 gene was induced by Ca（NO3）2. Its overexpression enhanced nitrogen uptake and carbon assimilation in transgenic sweetpotato. After Ca（^15NO3）2 treatment, the -（15）N atom excess, -（15）N and total N content and nitrogen uptake efficiency（NUE） were significantly increased in the roots, stems, and leaves of transgenic plants compared with wild type（WT） and empty vector control（VC）. After Ca（NO3）2 treatment, the increased nitrate N content, nitrate reductase（NR） activity, free amino acid content, and soluble protein content were found in the roots or leaves of transgenic plants. The photosynthesis and carbon assimilation were enhanced. These results suggest that the IbSnRK1 gene play a important role in nitrogen uptake and carbon assimilation of sweetpotato. This gene has the potential to be used for improving the yield and quality of sweetpotato.

关键词： carbon assimilation IbSnRK1 nitrogen uptake sweetpotato

Application and Numerical Simulation of Electromagnetic Stirring in Secondary Cooling Zone During Continuous Casting of Ultra-Thick Slab

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2012年第S2期19卷 977-982页

作者： QU Tian-peng ren Bing-zhi HAN zhi-wei FENG Ke CISDI Chongqing Iron & Steel making Plant Integration Co. Ltd.

The segregation of solute elements at solidification front could be greatly improved by application of electromagnetic stirring(SEM)in secondary cooling *** location of SEM in secondary cooling zone affects the operational *** the present study,based on the application of SEM in Ultra-thick slab continuous casting,the shell thickness was calculated by self-programming code and the results were verified by nail-shooting test.A numerical model was established to calculate the fluid flow of molten steel under shell to determine the suitable SEM location in secondary cooling *** results shows that the velocity of molten steel increases with increase of stirring current which enhance the circulatory flow of unset steel at solidification ***,in order to fully develop ability of SEM it is necessary to select suitable stirring current and mode for ultra-thick slab *** calculation provides theoretical base for application of SEM in secondary cooling zone during ultra-thick slab casting process.

关键词： Electromagnetic stirring Secondary cooling zone Ultra-thick slab Continuous casting

座舱盖作动筒接管嘴断裂研究及施胶粘接密封改进

在线全文

学校读者我要写书评

暂无评论

机械研究与应用 2024年第3期37卷 111-114页

作者：马良冬刘震任宗强皮月亮任义志倪伟欧阳康国营芜湖机械厂安徽芜湖241000 中国航空制造技术研究院北京100000

为解决某装备救生系统座舱盖作动筒液压腔接管嘴断裂导致的座舱盖下降问题,该文对产品的机上安装受力状态、产品工作原理、接管嘴无损检测、失效情况等展开分析,采取有限元仿真模拟和故障复现等手段确定了断裂原因为外力过载。结合故障... 详细信息

为解决某装备救生系统座舱盖作动筒液压腔接管嘴断裂导致的座舱盖下降问题,该文对产品的机上安装受力状态、产品工作原理、接管嘴无损检测、失效情况等展开分析,采取有限元仿真模拟和故障复现等手段确定了断裂原因为外力过载。结合故障原因以及断裂后引发的质量安全风险,制定了一系列措施,以杜绝因误操作等因素导致的接管嘴断裂的情况,确保产品性能稳定可靠。

关键词：接管嘴断裂失效分析有限元分析过载

Factors influencing postoperative mortality one year after surgery for hip fracture in Chinese elderly population

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2013年第14期126卷 2715-2719页

作者： LI Shao-guang SUN Tian-sheng LIU zhi ren Ji-xin LIU Bo GAO Yang Department of Orthopedics Beijing Army General Hospital Beijing 100700 China

Background Disability and death following hip fracture is becoming more common as the population ages. Previous reports have focused on the selection of internal fixation methods and the analysis of the perioperative therapeutic results in the Chinese population. Few studies have focused on factors influencing medium and long term survival after surgery for hip fracture. We conducted a retrospective study on the factors influencing survival one year after hip fracture surgery in our elderly Chinese population to provide a reference for improved treatment and to enhance efficacy. Methods Records from patients undergoing treatment for hip fracture at our hospital from October 2009 through June 2011 were retrospectively reviewed. Through telephone follow-up, the health condition of each patient was surveyed, and the 1-year postoperative mortality was analyzed. The patients＇ age, gender, fracture type, pre-injury health condition, mobility, complications, surgical timing, surgical types, methods of anesthesia, and postoperative complications were analyzed. Univariate and multivariate regression analysis was performed on relevant influencing factors. Results A total of 184 patients had complete data and were followed-up for 12-23 months （average, 16.5 months）. There were 30 deaths （16.3%） at one-year. Univariate analysis revealed that factors such as age, gender, fracture-type, number of co-existing diseases, complications such as chronic obstructive pulmonary disease or sequelae of stroke, American society of Anesthesiology （ASA） scores, anesthesia methods, pre-injury activity, and post-operative complications were significantly different between survival versus mortality groups （P 〈0.05）. Multivariate regression analysis revealed that age, ASA score, pre-injury mobility and combined chronic obstructive pulmonary disease were independent risk factors for death. Conclusion Full consideration of medium-/long-term risk factors in the treatment of hip fracture in the elderl

关键词： elderly hip fracture mortality risk factors

垂穗披碱草根际促生菌的分离鉴定及促生作用研究

在线全文

学校读者我要写书评

暂无评论

草地学报 2024年第6期32卷 1693-1701页

作者：任智慧于乔高士孔王家驹牛德鹏刘美丽呼天明付娟娟西北农林科技大学草业与草原学院陕西杨凌712100 神木市畜牧业发展中心陕西榆林719300

优良的根际生长促生菌(Plant growth-promoting rhizobacteria, PGPR)是生产优质微生物菌肥的重要物质基础。本研究以广布于青藏高原的垂穗披碱草(Campeiostachys nutans Griseb.)为材料,采用平板划线法分离其PGPR,探究菌株的促生特性,... 详细信息

优良的根际生长促生菌(Plant growth-promoting rhizobacteria, PGPR)是生产优质微生物菌肥的重要物质基础。本研究以广布于青藏高原的垂穗披碱草(Campeiostachys nutans Griseb.)为材料,采用平板划线法分离其PGPR,探究菌株的促生特性,通过16S测序确定菌株的分类地位,并进行盆栽试验验证PGPR的促生效果。结果表明,从垂穗披碱草根际土筛选出14株促生特性优良的PGPR,其中,有11株兼具产IAA,ACC脱氨酶以及铁载体的能力。经16S rDNA鉴定,以假单胞菌属为优势菌属,6株属于假单胞菌属(Pseudomonas),2株属于芽孢杆菌属(Bacillus),2株属于葡萄球菌属(Staphylococcus),其他四株分别属于类节杆菌属(Paenarthrobacter)、微杆菌属(Microbacterium)、不动杆菌属(Acinetobacter)和考克氏菌属(Kocuria)。盆栽试验表明,接种14株菌株对多年生黑麦草具有良好的促生效果,并能够提高其光合效率。研究结果丰富了植物根际促生菌菌种资源库,为实现农业“绿色增产”提供优质菌肥种质资源。

关键词：青藏高原垂穗披碱草根际促生菌分离筛选促生作用

维普期刊数据库博看期刊

Fluorescence-Detected Ultrafast Free-Induction Decay in Powdered Rare Earth Solids

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第2期17卷 101-103页

作者： LUO Qi DAI De-Chang YU Xiang-Yang QIU zhi-ren ZHOU Jian-Ying YAN Chun-Hua CHEN zhi-Da State Key Laboratory of Ultrafast Laser Spectroscopy Zhongshan UniversityGuangzhou 510275 State Key Laboratory of Rare Earth Materials Chermistry and Applications Peking UniversityBeijing 100871

Fluorescence interferometry is developed and applied to study ultrafast amplitude and phase dynamics for fleeinduction decay in powdered rare earth solids. The time-resolved phase dynamics of free-induction decay throughout the decaying process is accurately determined by using a novel dual-channel correlation technique and subpicosecond dephasing time is measured for Nd3+ solids at room temperature. The phase dynamics is well simulated with linear coherent polarization theory.

关键词： temperature theory Fluorescence

Hematopoiesis reconstitution and anti-tumor effectiveness of Pai-Neng-Da capsule in acute leukemia patients with haploidentical hematopoietic stem cell transplantation

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

World Journal of Clinical Cases 2022年第14期10卷 4425-4435页

作者： Jiao-Jiao Yuan Ying Lu Jun-Jie Cao ren-zhi Pei Rui-Lan Gao Department of Hematology The Affiliated People’s Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina Institute of Hematology Research The First Affiliated Hospital of Zhejiang Chinese Medical UniversityHang Zhou 310006Zhejiang ProvinceChina

BACKGROUND With the rapid development of haploidentical hematopoietic stem cell transplantation(haplo-HSCT),primary poor graft function(PGF)has become a lifethreatening *** therapies for PGF are *** Chinese patent medicine Pai-Neng-Da(PND)Capsule exerts dual effect in promoting hematopoiesis recovery and regulating ***,the application of PND capsule in hematopoietic stem cell transplantation,especially in the haplo-HSCT setting,has not yet been *** To evaluate the role of PND capsule in acute leukemia patients with *** We retrospectively collected data of acute leukemia patients who underwent haplo-HSCT at the Affiliated People’s Hospital of Ningbo University between April 1,2015 and June 30,***-nine consecutive patients received oral PND capsule from the sixth day to the first month after haplo-HSCT were included in the PND *** addition,31 patients who did not receive PND capsule during haplo-HSCT were included in the non-PND ***,we compared the therapeutic efficacy according to the western medical evaluation indexes and Chinese medical symptom scores,and the survival between the PND group and the non-PND group,using the chi-square test,Fisher’s exact test,and the Kaplan-Meier *** The duration of platelet engraftment was shorter in the PND group than in the non-PND group(P=0.039).The PND group received a lower frequency of red blood cells and platelet transfusions than the non-PND group(P=0.033 and P=0.035,respectively).In addition,PND capsule marginally reduced the rate of PGF(P=0.027)and relapse(P=0.043).After 33(range,4-106)months of follow-up,the 3-year relapse-free survival(P=0.046)and progression-free survival(P=0.049)were improved in the PND group than in the non-PND ***,the therapeutic efficacy of the PND group according to Chinese medical symptom scores was significantly better than that of the non-PND group(P=0.022).Moreover,the adverse events

关键词： Pai-Neng-Da capsule Hematopoiesis reconstitution Anti-tumor Acute leukemia Haploidentical hematopoietic stem cell transplantation Effectiveness