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241.
休闲农业是农业和旅游业相结合的现代新兴交叉产业,以辽宁为例探讨休闲农业的发展具有现实意义。在介绍我国休闲农业发展背景的基础上,对休闲农业的概念进行了解读,从辽宁休闲农业发展现状入手,采用PEST分析法和SWOT分析法,对休闲农业的内部发展潜力和外部发展环境进行剖析,并据此提出促进辽宁省休闲农业发展的战略措施。 相似文献
242.
甜玉米的蒸煮品质品尝鉴评是评价食味品质的重要环节。了解普通消费者评价甜玉米食味品质的标准及偏好性可以使育种家在改良甜玉米品质和培育优质品种时更有针对性。以17份甜玉米种质为试验材料,在专业鉴评的基础上,请95名普通消费者进行了品尝鉴评,并对获得的评价数据进行调查。普通消费者的评价结果总体上和专业鉴评结果相一致;与好吃程度相关性最高的是风味和甜度,相关系数均在0.950以上;女性普通消费者中果皮厚度与好吃程度的相关系数高达0.930以上,显著高于男性的0.892,而女性消费者中好吃程度与光泽度的相关系数则只有0.501,明显低于男性的0.666。上述结果表明,与普通消费者整体喜好度相关性最高的是风味和甜度;女性消费者对果皮厚度的重视程度高于男性,而男性消费者对光泽度的重视程度高于女性。这些初步调查结果可为育种家们开展更有针对性的甜玉米食味品质改良提供参考依据。 相似文献
243.
为探究打顶时期与留叶数对山东烤烟上部叶生长发育的影响,以中烟100为材料,设置6个不同的打顶时期与留叶数处理,并对上部叶农艺性状、光合特性、碳氮代谢、衰老特性、烤后烟叶化学成分、感官评吸质量及经济性状进行了分析。结果表明,同一打顶时期,多留叶有利于抑制成熟后期上部叶强盛的光合能力,留叶18及20片处理有利于上部叶开片,后期抗氧化酶及NR活性较低,NI活性较高,落黄较快,烤后烟叶化学成分协调,经济性状优良。初花打顶以留叶20片处理品质较好,盛花打顶以留叶18片处理品质较好。同一留叶水平以初花打顶烟叶长宽比适宜,叶面积较大,开片较好,烟叶感官品质较好。综合来看,以初花打顶、留叶20片处理上部叶农艺性状较优,化学成分协调,感官质量较好。 相似文献
244.
The advancing global urbanization puts great pressure on the society and ecosystem, especially in developing countries. Reasonable land-use policies adapted to local conditions are the key issues to prevent disordered urban expansion. Multi-scenario simulation provides a new perspective for differentiated policy formulation based on regional heterogeneity. Regarding the Shaanxi Province, a rapid urbanized area with high spatial heterogeneity in western China, as the study case, we tracked its past land-use changes and predicted the characteristics of urban expansion using the Future Urban-Regional Environment Simulation model. We found that (1) during the past 35 years, built-up land evidently increased accompanied by the loss of cropland, grassland, and unused land. (2) The urban expansion mainly will occur in the areas with flat terrain under three scenarios. (3) The urban expansion will transit into the “requiring land from mountains” pattern in the future, which means that it will gradually spread to areas with higher slopes. (4) Differentiated and optimal development patterns are proposed for different subregions by accounting the loss of ecosystem service in the procedure of urban expansion. This research can help local governments formulate differentiated future macro control of territorial spatial planning to optimize subregional land development. 相似文献
245.
This paper investigates how human capital agglomeration interplays with institutional factors to affect migration destination choice in China. Over the last decades, China has experienced massive internal migration, substantial human capital investment, and the relaxation of its hukou system, thus providing us with a valuable opportunity to examine the role of human capital externality in migration choice. Based on rich data on province-to-province migration flows for different education and hukou groups, we find that migrants in China, especially highly educated and urban-to-urban migrants, have a strong preference to move to provinces with a high agglomeration of human capital. Further examination reveals that low-skilled migrants in China are less likely to benefit from human capital agglomeration because of their lower ability to overcome hukou restrictions. Our findings raise the concern that labor migration under the skill-biased hukou system would enlarge China's regional disparities in human capital and economic development. 相似文献
246.
豇豆胰蛋白酶抑制剂转基因棉花的获得 总被引:22,自引:10,他引:22
利用根癌农杆菌(Agrobacteriumtumefaciens)介导法将豇豆胰蛋白酶抑制剂(Cow-peaTrypsinInhibitor,CpTI)基因转移进入棉花(GosypiumhirsutumL.)。棉花幼苗的下胚轴与携带有CpTI基因和Npt-Ⅱ基因的根癌农杆菌共培养,在选择培养基上诱导出了卡那霉素抗性(Kmr)愈伤组织。选择Npt-Ⅱ阳性的胚性愈伤组织在胚状体诱导培养基上进行胚状体诱导,继而在分化培养基上进行植株分化,最终获得了再生棉花植株。经Npt-Ⅱ分析、PCR及Southern检测证明,外源CpTI基因和标记基因(Npt-Ⅱ基因)存在于转化棉株及其后代中。抗棉铃虫(Heliothisarmigera)生物活性检测表明转基因植株后代具有明显的抗棉铃虫能力。 相似文献
247.
China's stock market enters a stage where the competition's rules as well as the competition's environment are changing continuously,Under such circumstances,to gain the competition advantages is of vital importarce to the existence and development of China's stock companies themselves. As a result, the stock companies should have a thorough analysis of the RBV theory at present, and evaluate its applicability to China's stock companies, Then they should come up with some reformational measures,aiming at improving the competition advantages of domestic stock companies. There fore they are able to make measonable use of the company's resources and accomplish the organic unity combination of the company's valued resources and its strategic administration. These are the key measures used by stock companies to gain the competition cedvantges. 相似文献
248.
The situation and the future of the automotive industry information construction is shown in this paper. The significance of Chinese automotive industry information construction is discussed,and the technology base and system structure is also described. The function and the structure of information system by one application of marketing plotting system in one automobile factory's E-commerce are introduced.The important significance for develop and research of product and strategic decision is shown by building market demand information system. 相似文献
249.
According to the graphics characteristics of metallic doors & windows design and based on the research of graphics dimension restriction problems. This paper provides a new method for parameterized design of metallic doors & windows in virtue of expression solution. In this method, the restrictions of graphic elements have been changed into the parameter expressions of sizes and positions of graphic elements. Through the calculation of such expressions, the parameter driven method has been reached. Thus the parameterization of graphics can be easier and quicker than before. It can be used to setup the open parameterized graphics libraries. 相似文献
250.
Larger quantities of data about flight performance and flight condition are recorded by flight data recorder (FDR) during the aircraft's flying. It is an importance task to make 3D flying animation from the data on the process of flight data. The design ideas and realizing methods about the software of flying animation system driven by the data from relation database are presented. 相似文献