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Search Results: 1 - 10 of 249491 matches for " 张姗姗 "
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MSLB事故对主控制室剂量影响研究
Study on the Influence of MSLB Accident on Main Control Room Dose
 [PDF]

孙大威, 潘楠, 姗姗
Nuclear Science and Technology (NST) , 2015, DOI: 10.12677/NST.2015.34018
Abstract: 本文深入的阐述了AP1000主蒸汽管道破裂事故(MSLB)剂量分析基本方法,介绍了一回路、二回路初始放射性释放及碘尖峰释放三种方式的源项计算模型。以AP1000滨海厂址为例,分别评估了MSLB事故后应急可居留系统(VES)模式和非放射性通风系统(VBS)新风过滤模式投入情况下主控制室(MCR)内工作人员的剂量,其剂量结果均可满足HAD 002/01-2010限值要求,事故后主控制室具有良好的可居留性。同时,针对VES投入情况下主控制室剂量影响参数,开展了详细的敏感性分析。研究结果表明,二回路初始存在的碘及碱金属对剂量贡献最大;MCR剂量主要来自于0.052~4 h时间段,由VBS正常通风引入的放射性所产生;破损SG喷放时间、VES模式开始时间、MCR内循环风量为剂量敏感参数,MCR内渗透率、辅助风机风量为剂量不敏感参数。相关研究结论可为优化主控制室设计提供必要的理论参考。
In this paper, main steam line break (MSLB) accident dose assessment method on AP1000 is ela-borated, and three types of radiation source term analysis models are expounded, involving the primary coolant initial activity release, secondary coolant initial activity release and iodine spike release. Based on the AP1000 coastal site, the main control room (MCR) personal doses are eva-luated, during operation of emergency habitability system (VES) mode and nuclear island nonra-dioactive ventilation system (VBS) supplemental air filtration mode, respectively. All the above results can meet the requirement of HAD 002/01-2010, and the main control room has good habi-tability. Meanwhile, detailed parameter sensitivity analysis is performed for MCR dose based on VES mode. Research results have shown that the initial secondary iodine and alkali metals release makes the largest contribution to MCR dose, and the MCR dose mainly results from the VBS normal operation mode activity introduction during the period of 0.052~4 h. The blowdown period of SG, beginning time of VES mode, and recirculation flow are the sensitive parameters to MCR dose, but the in-leakage rate and auxiliary fan flow are insensitive parameters. These research conclusions could provide necessary theory reference to MCR design optimization.

夏季室外光生物反应器培养Chlorella sorokiniana
姗姗,刘和
- , 2015, DOI: 10.3969/j.issn.1673-1689.2015.03.006
Abstract: 搭建了一个6 L容积曝气型垂直柱光生物反应器,在6-8月期间置于室外屋顶运行,旨在考察夏季室外培养微藻Chlorella sorokiniana的可行性。室外培养时,若pH超过8.5,微藻会出现明显絮凝沉淀现象。太阳光入射到反应器的高达(1 700±137) ?滋mol/(m2·s)的光照强度带来的光抑制作用及随之引起的超过48 ℃的高温,对微藻细胞的损伤造成了室外培养的抑制现象。当培养液温度超过40 ℃时,Chlorella sorokiniana几乎不能生长。在反应器周围放置金属镀层反射隔热膜反射板,可以减少(42.21±4.7)%的光照强度,使培养液温度下降2~4 ℃,但晴天时光照强度仍然可达900 ?滋mol/(m2·s)以上,光抑制作用不能很好被解除。为实现微藻在室外反应器中可持续地快速增长,仍需进一步采取措施减弱光照强度。
Aimed to investigate the feasibility of growing Chlorella sorokiniana outdoor in summer,a 6 L aerated vertical column photobioreactor was performed from Jun to Aug on the rooftop. When cultivated outdoor,algae auto-flocculation will happen heavily once pH was over 8.5. The photoinhibition caused by high incident light intensity(1 700±137 ?滋mol/(m2·s))and the algal cells damage resulted from high temperature(48 ℃) lead to inhibition of algal growth. Chlorella sorokiniana is not able to grow well when temperature is over 40 ℃. The installation of reflectors,which covered by reflective thermal insulation mental coatings,could decrease light intensity by 42.21±4.7%,resulting in 2~4 ℃ temperature decrease. However,light intensity still could be more than 900 ?滋mol/(m2·s) on sunny days,making photoinhibition hard to be relieved. To achieve faster algal growth as well as continuous cultivation outdoor,more effort should be made to moderate the light intensity
薯类植物中的淀粉生物合成及关键酶
Starch Biosynthesis and the Key Enzymes of Root and Tuber Plants
 [PDF]

姗姗, 杨俊, 周文智,
Botanical Research (BR) , 2013, DOI: 10.12677/BR.2013.21005
Abstract:

薯类作物富含淀粉,是我国重要的粮食和食品加工原料,也是变性淀粉和生物质能源的优势原材料。淀粉包含直链淀粉和支链淀粉两种组分,生物合成是其唯一的来源。各类作物中淀粉生物合成由多种功能保守的关键酶类相互协调、共同作用来完成。根据其功能,这些酶分为ADP葡萄糖焦磷酸化酶、淀粉合成酶、淀粉分支酶、淀粉去分支酶等。本文综述了近年来这些关键酶在生物学功能及作用机制上的新进展,分析了淀粉合成过程中可能包含的新酶种类如淀粉磷酸化酶、D-酶等的功能,并总结了这些酶类在薯类作物直链淀粉和支链淀粉合成中的功能特点。这为开展薯类作物中淀粉合成酶的鉴别和功能研究,以及建立薯类淀粉结构与性质的关联性提供了重要的参考。
The tuber and root crops are rich in starch in their storage organs and provide important raw mate- rials not only for food and processed food, but also for modified starches and bioenergy. Starch is composed of two types of molecules, amylose and amylopectin. It can only be produced through biosynthetic pathway, a process that involves multiple enzymes of conserved functions in many crops, such as ADP-glucose phos- phorylase, starch synthases, starch branching enzymes and starch debranching enzymes. Here we review re- cent progresses in biological functions and mechanisms of these key enzymes in starch biosynthesis, include- ing new identified enzymes such as starch phosphorylase and D-enzyme. Their features in amylose and amy- lopectin biosynthesis of tuber and root crops were also explored. It not only provides important information for identification and functional analysis of key enzymes in starch biosynthesis but also bridges the gap be- tween starch structure and property of tuber and root crops.

D(-)-二吡啶甲基酒石酸酰胺在不对称氧化合成埃索美拉唑中的应用
姗姗,月成
分子催化 , 2012,
Abstract: D(-)-酒石酸二乙酯(1)分别与2-氨甲基吡啶和4-氨甲基吡啶反应,合成了D(-)-二吡啶甲基酒石酸酰胺2和3。分别以1~3为手性配体与钛酸异丙酯配合,催化过氧化氢异丙苯(CHP)不对称氧化埃索美拉唑前体(Eso-I)合成埃索美拉唑。结果表明,由配体2或3构成的催化体系在埃索美拉唑合成上显示出较高的催化活性和对映选择性。例如,当以2为配体,甲苯为溶剂,在优化的条件下进行反应时,Eso-I的转化率达84.7%,埃索美拉唑的选择性达91.8%,对映体过量值达89.0%。
不同施肥结构和酸调理剂对酸性红菜园土的修复效应
姗姗,杨珠
湖南农业大学学报(自然科学版) , 2012,
Abstract: 采用田间小区试验,研究不同施肥结构和酸调理剂对由第四纪红土发育的酸性红菜园土的酸性、有效养分以及作物产量的影响。结果表明:不同施肥处理间的土壤碱解氮含量差异有统计学意义,辣椒季、小白菜季均以化肥(NPK)处理(40d)最高,辣椒季为(156.80±23.38) mg/kg,小白菜季为(349.35±7.29) mg/kg;有效磷含量辣椒季以化肥处理(60d)最高,为(160.35±31.21) mg/kg,小白菜季以化肥+氧化镁(NPK+MgO)处理的最高,为(211.13±7.34) mg/kg;速效钾含量以化肥+酸化调理剂1号(NPK+SR1)处理的最高,辣椒季均值为(155.6±16.65) mg/kg,小白菜季均值为(278.91±3.5) mg/kg;不同施肥处理对土壤pH、交换性酸(EA)和土壤酸碱缓冲容量(pHBC)影响明显,以化肥+氧化钙(NPK+CaO)、化肥+氧化镁(NPK+MgO)处理能明显降低土壤交换性酸,提高土壤pH和土壤酸碱缓冲容量(pHBC),其pH均值分别提高了1.23和1.7,土壤pHBC值分别达45.9 mmol/kg和49.0 mmol/kg,其他处理的土壤pHBC值仅30 mmol/kg左右;不同处理作物的产量差异有统计学意义,其中辣椒季以化肥(NPK)处理的产量最高,增产率为226.9%,小白菜季以化肥+氧化镁(NPK+MgO)处理的产量最高,增产率为58.7%,施用CaO、MgO能有效降低酸性菜园土的酸性,促进作物显著增产。
农村公共服务支出的济贫效应分析——以贵州省为例
Analysis of Poverty Relieving Effect of Rural Public Service Expenditure——A Case Study of Guizhou Province

姗姗,吴春梅
- , 2016,
Abstract: 对1978-2013年全国的及1978-2014年贵州省的农村公共服务支出与贫困减少的数据进行回归分析,均发现农村公共服务支出对减少农民贫困具有正向促进作用,即农村公共服务支出具有济贫效应。进一步,在对贵州省10个贫困村庄实地调查数据进行因子分析的基础上做回归分析,结果显示农民对本地公共服务供给的满意程度越高,其人均收入水平就越高,这从侧面体现了农村公共服务支出的济贫效应。针对贵州省落后的农村公共服务水平,政府应该在总体规划、农户满意度和基础设施建设中加快推进农村贫困地区的基本公共服务建设、农民主体性建设、特色文化与配套措施建设,创设反贫困的环境条件、内在条件和保障条件,以充分发挥农村公共服务支出在贵州省的济贫效应。
The Data analysis of national 1978-2013time series and 1978-2014time series in Guizhou both show that the expenditure of national rural public service has positive effect to relieve poverty. Meanwhile, regression analysis based on factor analysis of the field survey data in 10 poor villages in Guizhou shows that the higher the satisfaction degree of farmers to the local public service supply is, the higher the level of their income is, which indirectly reflects the poverty relieving function of the rural public service expenditure. In view of the backward rural public service level in Guizhou, it is necessary for the government to make an overall plan, elevate famers’ satisfaction level and speed up the infrastructure construction so as to better the public services, farmers’ subjectivity, local culture and supporting facility in poor rural areas. In addition, qualified environmental condition, internal condition and guarantee condition serve to amplify the poverty relieving function of rural public service expenditure in Guizhou.
基于数据映射算法的近邻存储方法研究
Research on the Method of Neighbour Storage Based on Data Mapping Algorithm
 [PDF]

姗姗
Hans Journal of Data Mining (HJDM) , 2016, DOI: 10.12677/HJDM.2016.64016
Abstract:
随着互联网的高速发展,如何有效地存储海量数据以提供高效的查询效率是一项亟待解决的关键问题。然而,采用现有的例如Chord和P2P等分布式存储方案,面对高维、海量的存储数据时,数据存储规模和开销不断增加,造成存储效率以及数据查询效率不断降低。本文提出了基于数据映射算法的近邻存储方法。实验表明当进行相关性查询时,提高了查询准确率,同时显著降低了网络带宽。
With the high-speed development of the Internet, processing of high-dimensional and massive amounts of data for querying is a key challenge. However, for the traditional distributed storage scheme, such as the P2P network and Chord, the data storage capacity and the switch overheads from the nodes are increasing, thus decreasing the storage efficiency and data query efficiency continuously. In this article, a neighbor data storage approach based on data mapping algorithm is proposed. The experiment results show that the proposed method can improve the query accuracy rate and reduce network bandwidth through relevant query.
掺粉煤灰和矿渣粉的活性粉末混凝土梁受力性能试验研究
郑文忠,姗姗,明辉
建筑结构学报 , 2009,
Abstract: 根据棱柱体试件的受压试验结果,得到了常温养护下活性粉末混凝土(RPC)的优选配合比和基于该配合比的受压应力-应变曲线上升段方程。根据5根钢筋RPC梁受弯性能试验,获得了这类梁纯弯区段在各级荷载作用下受压边缘压应变及应变沿梁高的分布、开裂荷载和极限荷载、各级荷载作用下的变形及裂缝分布与开展,由试验数据可知,相同条件下这类梁的变形及裂缝宽度均比普通钢筋混凝土梁稍大。通过假定用于受弯承载力计算的RPC受压应力-应变曲线关系下降段为直线,结合试验数据分析,获得与极限压应变相对应的RPC压应力的大小,从而得到RPC应力-应变全曲线方程。基于RPC的受压应力-应变全曲线方程建立了RPC梁正截面承载力计算方法。同时基于试验结果给出了在使用荷载作用下这类梁刚度和裂缝的计算方法。
基于集对分析和主成分分析的中国沿海省海洋产业竞争力评价
姗姗,凤成,曹可
资源科学 , 2014,
Abstract: 科学评价沿海各省海洋产业竞争力对于寻找竞争优势、改善竞争劣势、合理制定海洋产业发展战略和规划具有重要意义.本文综合考虑海洋资源环境条件、海洋经济产值、海洋产品产量、区域社会经济支撑等多种因素及其内部相互作用,建立了21个评价指标的省级海洋产业竞争力评价指标体系.以2011年海洋经济统计数据为基础,应用集对分析和主成分分析的方法,分别对11个沿海省(区、市)海洋产业竞争力进行了测算,根据两种分析方法的综合得分,将海洋产业竞争力划分3个层次:广东、山东竞争力最强,应进一步发挥优势,有效提高海洋资源的集约利用水平;天津、河北、辽宁、上海、江苏、浙江、福建竞争力处于中等水平,其中,天津和上海应进一步发挥科技支撑作用,发展优势产业和高新技术产业,其他地区应充分发挥资源优势,加大海洋资源的开发力度,壮大海洋产业;广西、海南竞争力最弱,应深入挖掘发展潜力,加大科技投入,提升海洋产业规模.
高效液相色谱-质谱法测定花生中的植物螯合肽
,王颜红,姗姗
分析化学 , 2009,
Abstract: 以镉胁迫花生为原料,建立了液相色谱-电喷雾电离质谱联用仪测定花生中的植物螯合肽的LC-MS方法。以C18反相柱为分析柱,1%三氟乙酸、乙腈为梯度洗脱淋洗液,能够检测出花生中的植物螯合肽。在本实验条件下,检出限为0.2mg/L;线性范围在0.50~20.0mg/L(r≥0.9974);回收率大于80%。方法灵敏度高,实用性强。应用本方法对实际花生样品中的PC4进行了定量分析。初步证实了花生中存在丙氨酸类植物螯合肽。结果表明,受镉胁迫的花生中均检出不同浓度的PC4。
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