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51.
52.
郑振鹏 《农业图书情报学刊》2011,23(1):87-89,93
文献财产号是图书馆文献财产有效管理手段,是图书在流通中借还和书目查询的基础和依据。由于文献财产号相对比较长,编目输入时容易出错,且编目校对时不够仔细和严格,使得馆藏数据库中出现财产号错误的现象,这将引起流通中错号图书不能外借,增加了图书的拒借率,同时也影响书目数据的质量,从而影响到图书馆自动化管理系统的正常运行和功能实现。针对此问题讨论了如何设计和开发一个基于SUL-CMIS系统的文献财产号检测系统,以便能从馆藏数据库中检测出错误的文献财产号并修改。 相似文献
53.
精子介导生产转hCD59基因猪 总被引:9,自引:0,他引:9
为研究精子介导法生产异种器官移植用转基因猪的效率,将人膜反应性溶解抑制物(hCD59)基因与脂质体混合制成基因/脂质体复合物,分别采用睾丸注射法和基因脂质体复合物/精子共孵育法制备转人hCD59基因猪,其中睾丸注射法处理公猪1头,44 d后配母猪8头,7头受孕(受孕率87.5%),产仔73头,PCR阳性猪3头(阳性率4.3%);外源基因/精子共孵育法处理公猪4头,处理母猪4头,1头受孕(受孕率25%),产仔11头,PCR阳性猪1头(阳性率9%)。从15头受孕母猪共获得84只仔猪,经PCR初步检测,其中4只仔猪为转基因阳性,阳性率4.8%。研究结果表明:通过精子介导法可以获得转基因猪。 相似文献
54.
近年来,计算流体力学(CFD)技术随着计算机科学和流体力学理论的发展而在工业各领域得到广泛使用。用CFD技术对冷库开关门过程进行了非稳态数值模拟,分析了小型冷库开关门过程中门周边温度场的变化,讨论了外界环境对冷库影响的区域,研究模拟了开关门各20s过程的温度场变化情况,发现由冷热空气密度差引起的自然流动是门处空气流动的主要方式。研究表明关门后,冷库下部的空气温度场恢复较快,上部恢复较慢(10s以后才明显下降),20s后温度可大致恢复至开始状态。研究结果证明数值模拟能较好地反映现实情况。 相似文献
55.
烟叶仓库害虫高毒Bt菌株对烟叶品质的影响 总被引:3,自引:0,他引:3
苏云金杆菌Bacillus thuringiensis(Bt)Bt33、Bt53、BtHB是从736株野生型Bt菌中筛选分离的对烟叶仓库害虫烟草粉螟具有高效杀虫活性的菌株。为研究施用苏云金杆菌对烟叶品质的影响,对试验烟叶定期取样进行化学成分测定及单体烟评吸。结果表明,喷施苏云金杆菌菌剂Bt33、Bt53、BtHB后分别于3个月、6个月、9个月、12个月、15个月、18个月、21个月、24个月取样对烟叶化学成分进行分析,各处理总糖、还原糖、总氮、烟碱、蛋白质与同期对照相比,其含量差异不大。12个月后,喷施3种菌剂防治烟叶仓库害虫,其菌剂对烟叶主要香气成分无影响,部分烟叶香气成分可得到改善;单体烟评吸总分各处理均高于对照,香气质、香气量、杂气指标均优于对照。 相似文献
56.
57.
研制的麦秸氨化青贮料综合了氨化与青贮的优点,呈青贮料型。粗蛋白质含量(CP)提高1.5倍(9.69∶3.8l),代替麦秸和部分青贮饲喂奶牛比对照产标准乳提高22.62%(P<0.05);精料利用率提高21.36%,全日粮千物质利用率提高11.04%;吨奶饲料成本降低45.36元;利用青贮窖节省了昂贵的氨化设备;减少了青贮渗出液和氨化过程中氨的损失。为开发秸秆的饲用潜力开辟了新路。 相似文献
58.
In light of growing concerns about obesity, Winson (2004, Agriculture and Human Values 21(4): 299–312) calls for more research into the supermarket foodscape as a point of connection between consumers and food
choice. In this study, we systematically examine the marketing of ready-to-eat breakfast cereals to children in Toronto, Ontario
supermarkets. The supermarket cereal aisle is a relatively unstudied visual collage of competing brands, colors, spokes-characters,
and incentives aimed at influencing consumer choice. We found that breakfast cereal products with higher-than-average levels
of sugar, refined grains, and trans-fats are more likely to feature child-oriented marketing in the form of spokes-characters,
themed cereal shapes/colors, and child incentives on cereal boxes. These forms of visual communication are consistent with
a “health exploitive” pattern of targeted marketing to children in the supermarket setting. Only one aspect of visual communication
is consistent with a “health protective” pattern of marketing to children—cereals shelved within reach of children aged 4–8
had less sugar per serving and were less likely to contain trans-fats than less reachable products. We discuss the implications
of our findings for the measurement and regulation of marketing to children in North American supermarkets.
Brent Berry who has a PhD from the University of Michigan, is an Assistant Professor of Sociology at the University of Toronto in Ontario, Canada. His most recent research has sought to untangle the casual processes underlying socioeconomic disparities in health over the lifecourse. Brent has also developed innovative visual approaches for systematically studying interracial friendships, homelessness, and marketing in supermarkets. Brent has also published work on race and ethnic relations, residential segregation, social theory, and family intergenerational support. His work has been published in Demography, Health, Evaluation Review, Ethnic and Racial Studies, the Journal of Family Issues, and the American Journal of Economics and Sociology. Taralyn McMullen is a doctoral candidate in Sociology at the University of Toronto. Taralyn is interested in the sociology of health and illness, with emphasis on issues of food insecurity. In addition to her collaborative work with Brent Berry, Taralyn has completed a research project examining the link between food insecurity, obesity, and gender discrimination in Canada. 相似文献
Brent BerryEmail: |
Brent Berry who has a PhD from the University of Michigan, is an Assistant Professor of Sociology at the University of Toronto in Ontario, Canada. His most recent research has sought to untangle the casual processes underlying socioeconomic disparities in health over the lifecourse. Brent has also developed innovative visual approaches for systematically studying interracial friendships, homelessness, and marketing in supermarkets. Brent has also published work on race and ethnic relations, residential segregation, social theory, and family intergenerational support. His work has been published in Demography, Health, Evaluation Review, Ethnic and Racial Studies, the Journal of Family Issues, and the American Journal of Economics and Sociology. Taralyn McMullen is a doctoral candidate in Sociology at the University of Toronto. Taralyn is interested in the sociology of health and illness, with emphasis on issues of food insecurity. In addition to her collaborative work with Brent Berry, Taralyn has completed a research project examining the link between food insecurity, obesity, and gender discrimination in Canada. 相似文献
59.
60.
该文研究了北京地区钢结构组合式种子仓房夏季的温湿度及其分布。测试期间,仓外最高气温36.6℃,仓内最高平均空气温度为27.4℃,种堆最高平均温度为25.8℃,仓内外最高空气温差达到9.2℃,仓内空气与种堆最高温差1.6℃;种堆上层温度高于下层温度,但温度梯度较小,最大温差为0.5℃;种堆最高相对湿度为62%,表明该类型仓房内的温湿度条件能满足玉米、小麦等种子贮藏条件。仓房南墙内外墙体表面的最高温度差20.4℃,仓房北墙最高热流量为67.0 W/m2,南墙最高热流量为120.5 W/m2,表明该仓房墙壁密封性能较好。最后对仓房管理和需要进一步研究的方向提出了建议。 相似文献