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Journal of Iron and Steel Research International 2012年第10期19卷 64-73页

作者： G subhash chander G Madhusudhan Reddy A Venugopal Rao Swarna Bharathi Institute of Science and Technology Khammam 507002APIndia Defense Metallurgical Research Laboratory Kanchanbagh 500058APIndia

Fundamental investigation of continuous drive friction welding of austenitic stainless steel (AISI 304) and low alloy steel (AISI 4140) is described. The emphasis is made on the influence of rotational speed on the microstructure and mechanical properties such as hardness, tensile strength, notch tensile strength and impact toughness of the dissimilar joints. Hardness profiles across the weld show the interface is harder than the respective parent metals. In general, maximum peak hardness is observed on the stainless steel side, while other peak hardness is on the low alloy steel side. A trough in hardness distribution in between the peaks is located on the low alloy steel side. Peak hardness on the stainless steel and low alloy steel side close to the interface increases with a decrease in rotational speed. All transverse tensile joints fractured on stainless steel side near the interface. Notch tensile strength and impact toughness increase with increase in rotational speed up to 1 500 r/min and decrease thereafter. The mechanism of influence of rotational speed for the observed trends is discussed in the torque, displacement characteristics, heat generation, microstructure, fractography and mechanical properties.

关键词： friction welding dissimilar metal joint austenitic stainless steel low alloy steel microstructure impact toughness tensile strength

Thickness Dependent Physical Properties of Thermally Evaporated Nanocrystalline CdSe Thin Films

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1299-1304页

作者： Anuradha Purohit subhash chander Satya Pal Nehra Mahendra Singh Dhaka Department of Physics Mohanlal Sukhadia University Centre of Excellence for Energy and Environmental Studies Deenbandhu Chhotu Ram University of Science and Technology Microelectronics Research Center Iowa State University of Science and Technology

This paper presents a study on thickness dependent physical properties of cadmium selenide thin films. The films of thickness 445, 631 and 810 nm were deposited employing thermal evaporation technique on glass and ITO-coated glass substrates followed by thermal annealing in air atmosphere at 200 °C. These films were subjected to X-ray diffractometer, UV-Vis spectrophotometer, scanning electron microscopy（SEM） and electrometer for structural, optical,surface morphological and electrical analysis respectively. The structural analysis reveals that the films are nanocrystalline in nature with cubic phase and preferred orientation（111）. The crystallographic parameters such as lattice constant, interplanar spacing, grain size, internal strain, dislocation density, number of crystallites per unit area and texture coefficient are calculated and discussed. The optical band gap is found in the range 1.75-1.92 e V and observed to increase with *** SEM study shows that the annealed films are uniform, fully covered and well defined. The electrical analysis shows that the conductivity is varied with film thickness and found within the order of semiconductor behavior.

关键词： Thin films X-ray diffraction Optical properties Electrical properties Evaporation

Modulatory effects of Azadirachta indica on benzo(a)pyrene-induced forestomach tumorigenesis in mice

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World Journal of Gastroenterology 2006年第17期12卷 2749-2755页

作者： subhash chander Gangar Rajat Sandhir Durg Vijay Rai Ashwani Koul Department of Biophysics Basic Medical Sciences Block Panjab UniversityChandigarhPIN-160014India Department of Biochemistry Basic Medical Sciences Block Panjab UniversityChandigarhPIN-160014India

AIM： To evaluate the chemopreventive effects of aqueous Azadimchta indica （A indica） leaf extract （AAILE） against benzo（a）pyrene [B（a）P]-induced forestomach tumorigenesis in Balb/c mice. METHODS： Female Balb/c mice were divided into four groups of 10-12 animals each. For induction of forestomach tumors, starting from d 14 of the experiment, mice of B（a）P and B（a）P＋A indica groups were given intra-gastric instillations of B（a）P （40 mg/kg）, twice a week for four weeks. Mice ofA indica and B（a）P＋A indica groups were orally administered with AAILE （100 mg/kg）, two weeks prior to B（a）P instillations till the end of the experiment. After 22 wk of the first B（a）P instillation, mice were sacrificed and the forestomachs were analyzed for development of tumors, scanning electron microscopy （SEM） and histopathology. RESULTS： Tumor incidence was observed to be 100% in mice that received only B（a）P. However, treatment with AAILE reduced the tumor incidence by 58.4% as observed in mice of B（a）P＋A indica group when compared to that of B（a）P group. Similarly, the tumor burden and multiplicity were seen to decrease by 87.3% and 69.6% respectively in mice of B（a）P＋A indica group when compared to those of B（a）P group. Scanning electron microscopy analysis showed that AAILE treatment itself did not cause any abnormalities on the surface architecture of forestomach epithelium. In tumorous forestomach, surface disruption was observed. Over the forestomach tumors of B（a）P group of mice certain rounded structures were seen in addition to closely placed tongue-shaped squamous cells. Interestingly, these rounded structures were not observed in B（a）P ＋ A indica group of mice. Histopathalogically, the tumors were identical and diagnosed to be papillomas. Mice from control and A indica groups of mice did not develop any forestomach tumors and showed normal histo-architecture. CONCLUSION： The present data suggest that A indica exerts chemopreventive effects against B（a）P-induced forestomac

关键词： Azadirachta indica Benzo(a)pyrene, Chemoprevention Histopathology Scanning electron microscopy

Genetic dissection of carotenoids in maize kernels using high-density single nucleotide polymorphism markers in a recombinant inbred line population

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The Crop Journal 2017年第1期5卷 63-72页

作者： Orawan Jittham Xiuyi Fu Jing Xu subhash chander Jiansheng Li Xiaohong Yang National Maize Improvement Center of China/Beijing Key Laboratory of Crop Genetic Improvement/China Agricultural University Beijing 100193China

Carotenoids are antioxidants and vitamin A precursors that have important roles in human health. Hence, improving the carotenoid contents in maize kernels is a priority objective for breeders in order to obtain nutritional biofortification outcomes. In the current study, the genetic architecture of carotenoids in maize kernels was explored using a recombinant inbred line(RIL) population derived from a cross between inbred lines By804 and B73. A total of 81 QTLs were detected by using a high-density bin map and a simple sequence repeat(SSR)-based linkage map, with one to seven QTLs for each trait explaining 4.21%–47.53% of the phenotypic variation. A comparison of the QTL mapping efficiency between the two linkage maps revealed that the high-density bin map had higher resolution. In the current study 46 additional QTLs were identified, with 16 being common with previous studies and14 newly identified. Among the results, 29.6%(24/81) of QTLs explained > 10% of the phenotypic variation in the RIL population, and 70.4%(57/81) explained ≤ 10%. These results suggest that a few large-effect QTLs, together with a variable number of minor-effect QTLs,contributed to most of the genetic components of carotenoids in maize kernels.

关键词： Carotenoids QTL mapping SNP SSR Zea mays

A genome scan for quantitative trait loci affecting grain yield and its components of maize both in single-and two-locus levels

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Chinese Science Bulletin 2006年第12期51卷 1452-1461页

作者： YAN Jianbing TANG Hua HUANG Yiqin ZHENG Yonglian subhash chander LI Jiansheng National Maize Improvement Center of China China Agricultural University Beijing 100094 China National Key Lab of Crop Genetic Improvement Huazhong Agricultural University Wuhan 430070 China

By adding thirty-one markers in the pre- vious linkage map, a new genetic linkage map con- taining 205 markers was constructed, spanning a total of 2305.4 cM with an average interval of 11.2 cM. The genotypic errors in the whole genome were de- tected by the statistical method and removed manu- ally. The precision of the linkage map was improved significantly. Main and epistatic QTL were detected by R/qtl, and main QTL were confirmed and refined by multiple interval mapping (MIM). Finally, MIM de- tected seven QTL for rows number, and five QTL for each grain yield, kernels per row and 100-kernel weight. The contribution to genetic variations of QTL varied from 35.3% for grain yield to 61.5% for rows number. Only kernels per row exhibited significant epistatic interactions between QTL. Twenty-four epistatic QTL were detected which distributed on almost all the ten chromosomes. About two-third epistatic QTL were observed between main QTL and another locus, which had no significant effects. These results indicate rather clearly that there are a number of QTL affecting trait expressions, not directly but indirectly through interactions with other loci. Thus, epistatic QTL effects may play a crucial role, if not more important than main QTL effects, in the genetic variation for the measured traits in present study.

关键词：基因扫描分子标记上位QTL 谷物玉米

Identification of unconditional and conditional QTL for oil, protein and starch content in maize

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The Crop Journal 2013年第1期1卷 34-42页

作者： Yuqiu Guo Xiaohong Yang subhash chander Jianbing Yan Jun Zhang Tongming Song Jiansheng Li National Maize Improvement Center of China Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Crop Research Institute Shandong Academy of Agricultural Sciences National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

Oil, protein and starch are key chemical components of maize kernels. A population of 245 recombinant inbred lines(RILs) derived from a cross between a high-oil inbred line, By804, and a regular inbred line, B73, was used to dissect the genetic interrelationships among oil, starch and protein content at the individual QTL level by unconditional and conditional QTL mapping. Combined phenotypic data over two years with a genetic linkage map constructed using 236 markers, nine, five and eight unconditional QTL were detected for oil, protein and starch content, respectively. Some QTL for oil, protein and starch content were clustered in the same genomic regions and the direction of their effects was consistent with the sign of their correlation. In conditional QTL mapping, 37(29/8) unconditional QTL were not detected or showed reduced effects, four QTL demonstrated similar effects under unconditional and conditional QTL mapping, and 17 additional QTL were identified by conditional QTL mapping. These results imply that there is a strong genetic relationship among oil, protein and starch content in maize kernels. The information generated in the present investigation could be helpful in marker-assisted breeding for maize varieties with desirable kernel quality traits.

关键词： Zea mays Oil Protein Starch Unconditional QTL Conditional QTL

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两个玉米自交系苗期叶温的干旱响应研究

作物杂志 2008年第6期 62-65页

作者：刘亚丁俊强 subhash chander 李建生中国农业大学国家玉米改良中心农业部基因组学与遗传改良重点实验室

利用远红外热成像系统的技术,研究玉米自交系综3与87-1苗期叶片对干旱的响应以及生物量的积累变化。结果表明,在遭受中度干旱胁迫的条件下,87-1的相对生物鲜重(0.716)及相对生物干重(0.799)显著高于综3(0.564,0.658),87-1的叶温差(0.30... 详细信息

利用远红外热成像系统的技术,研究玉米自交系综3与87-1苗期叶片对干旱的响应以及生物量的积累变化。结果表明,在遭受中度干旱胁迫的条件下,87-1的相对生物鲜重(0.716)及相对生物干重(0.799)显著高于综3(0.564,0.658),87-1的叶温差(0.30℃)显著高于综3(0.13℃)。通过离体叶片分析,综3离体叶片较87-1失水速率快,叶温在离体短时间内下降更低。表明在响应水分胁迫方面,87-1较综3叶片蒸发量小,叶温变化大,保水能力好,87-1表现出了更强的耐旱性。生物量积累与叶温差存在紧密的相关性,较高叶温差的基因型在遭受到水分胁迫时生物量积累更强。

关键词：玉米叶温远红外热成像干旱

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印度的印刷工业

印刷工业 2009年第5期4卷 25-26页

作者： subhash chander 全印度印刷商联合会

全印度印刷商联合会（AIFMP）成立于1953年，由印度政府认可，是印度印刷商的最高机构。全国各地57个协会都是它的会员。AIFMP努力促进南亚区域合作联盟国家中的印刷厂广泛合作，共创未来。

关键词：印度政府印刷工业区域合作印刷厂

玉米产量及构成因子主效和上位性QTL的全基因组扫描分析

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科学通报 2006年第12期51卷 1413-1421页

作者：严建兵汤华黄益勤郑用琏 subhash chander 李建生中国农业大学国家玉米改良中心华中农业大学作物遗传改良国家重点实验室武汉430070

在此前构建的含174个分子标记的连锁图基础上,新增31个分子标记,并利用统计分析的方法对基因型数据进行检测,剔除基因型明显有误的数据,构建了共包含205个分子标记,平均间距为11．2 cM,覆盖玉米全基因组10条染色体的分子标记连锁图．基... 详细信息

在此前构建的含174个分子标记的连锁图基础上,新增31个分子标记,并利用统计分析的方法对基因型数据进行检测,剔除基因型明显有误的数据,构建了共包含205个分子标记,平均间距为11．2 cM,覆盖玉米全基因组10条染色体的分子标记连锁图．基于统计学的基因型数据检测,能显著提高连锁图构建的准确性．结合一年两点6个重复的田间实验,利用软件R/qtl进行主效和上位性QTL分析,同时利用多区间作图法(MIM)验证主效QTL和主效QTL互作的真实性和位置．通过MIM方法,检测到控制产量、行粒数、行数和百粒重的主效QTL分别为5,5,7和5个,分别能解释35.3％,37．4％(含1个互作QTL),61．5％和39．7％的遗传变异;除行粒数的2个QTL之间存在显著性互作之外,其他性状的主效QTL之间都没有检测到显著性互作存在．同时,还检测到24个上位性互作QTL,这些OTL涉及的位点几乎分布于所有10条染色体．这些互作QTL以主效QTL与无显著效应基因座之间的互作居多,对所有4个性状而言比例接近三分之二．这也说明主效QTL除了单独起作用之外还可以通过与其他没有显著效应的基因座之间互作来影响性状表达．结果表明,上位性QTL在玉米产量性状的遗传中可能与主效QTL一样也起着重要的作用．

关键词：分子标记上位性QTL 数量性状遗传

基于基因型选择提高QTL作图的精度——以一个RIL群体为例(英文)

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Acta Genetica Sinica 2006年第7期33卷 617-624页

作者：严建兵汤继华孟义江马西青滕文涛 subhash chander 李林李建生中国农业大学国家玉米改良中心北京100094

以PCR为基础的分子标记以及其他检测技术的发展,使得大规模的标记分析成为现实。这也为通过大群体标记分析,然后基于基因型选择挑选合适的小群体,从而提高QTL定位准确性和精度提供了可能。以一个包含294个家系的重组自交系(RIL)群体为例... 详细信息

以PCR为基础的分子标记以及其他检测技术的发展,使得大规模的标记分析成为现实。这也为通过大群体标记分析,然后基于基因型选择挑选合适的小群体,从而提高QTL定位准确性和精度提供了可能。以一个包含294个家系的重组自交系(RIL)群体为例,通过基因型选择和随机选择的办法产生了一系列大小不等的亚群体,比较了两类群体QTL定位的结果。分析表明:相同大小的基因型选择群体与随机群体相比性状的表型分布都符合正态分布;标记的偏分离情况也没有明显的差别,都随着群体大小的增大,偏分离的比例也逐渐增大。但同等大小的基因型选择群体比随机群体的交换富集率(CE)要大,且随着选择强度的增大不断增大,如群体大小为270时,CE=1.04,群体大小为30时,CE=1.45。总体上,随着群体大小的增加,不管是随机群体还是选择群体,其QTL检测能力、灵敏性和特异性也随之增加,但选择群体的检测能力、灵敏性和特异性总体上要好于随机群体。当群体大于或等于240时,其QTL检测能力基本没有差别;群体大小大于或等于210时,其QTL检测的灵敏性和特异性也没有什么差别。这也说明:选择强度越大,效果越明显。以QTL1-LOD区间作为衡量QTL精度的一个指标,结果显示所有基因型选择群体都比相同大小随机群体的QTL定位精度高。目前QTL定位研究中,基因型数据较表型数据而言更容易准确获得,因此通过基因型选择可以更好的优化群体结构,减少田间实验的工作量,提高全基因组水平QTL作图的精度,为随后的QTL辅助选择和精细定位以及克隆提供帮助。

关键词：数量性状位点(QTL) 基因型选择重组自交系(RIL) QTL定位精度