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苏雅楠 《内蒙古科技与经济》2022,(12):62-63+158
文章基于科尔沁左翼后旗实地调查,对努古斯台镇雅莫嘎查黄牛家庭舍饲养殖模式、努古斯台嘎查白音淖尔小区集中养殖模式进行比较研究,以此分析乡村振兴战略视域下不同养殖模式的经济效果和生态效应,探讨哪一种养殖模式具有普适性,更能带动农牧户增收,对科尔沁左翼后旗养殖业的持续发展及乡村振兴具有重要意义。 相似文献
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一、猪的规模养殖与效益 1、猪的规模养殖是牧业产业化的必然趋势。目前我县正在实施国家下达的“瘦肉型猪规模养殖及产业化技术开发”的重大科技推广项目,项目要求:到2000年,全县实行专业化养殖的高瘦肉猪要达到20万头,占出栏总数的40％,各类养猪专业户要达到3700余户。养猪产业化要求集约化生产,并形成一定 相似文献
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本发明涉及一种兼具节水和安全功能的池塘养殖复合系统,属水产养殖技术领域。它由鱼池、人工湿地和生态沟渠3部分有机结合构成,以水流为载体,依次串联形成立体、多级利用、闭合循环的池塘养殖复合系统。鱼池废水通过人工湿地和沟渠进行水质净化、增氧、池塘静态养殖为微流水养殖,而达到池塘鱼类优质高效生态养殖的效果, 相似文献
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近几年来,黟县以市场为导向,大力宣传及普及科技知识,开展科技活动,推广农村实用技术,积极组织实施致富进位工程,加快了养殖业结构调整,促进养殖业迅速发展。畜牧及特色养殖已成为我县农村经济发展的主导产业之一。它在农业总产值所占的比重由原来的10％提高到目前的33.54％,养殖业的结构由常规养殖向多元化、特色化养殖发展。特种养殖,具有经济价值高、产品销路畅的特点,但也有投资大、技术要求高、市场分析不准确的 相似文献
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稻田养殖小龙虾可以增加稻田产量,增加农民收入,是实现生态养殖的代表模式之一,具有重要的推广意义。本文对稻田淡水养殖小龙虾的技术及注意事项进行了详细论述,对稻田淡水小龙虾的养殖具有重要借鉴意义。 相似文献
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Fara P 《Endeavour》2008,32(1):3-4
After he returned from his five-year expedition to the New World, Alexander von Humboldt promoted himself as a Romantic explorer. Although this image pervades British perceptions, political movements have fashioned different heroic versions of Humboldt in Germany and South America. 相似文献
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Our objectives for this article are twofold: first, to examine the convergence of nations with regard to ICT access; and second, to see whether countries in the same continental region (South and East Asia, West and Middle East Asia, Africa, Eastern Europe, Western Europe, North America, South America, and Oceania) or having same initial ICT access have coalesced into groups. We constructed an ICT access index using three indicators (mobile phone, Internet, and broadband use per 100 population) for a sample of 198 nations for the 16-year period from 2000 to 2015. Results show that digital divide has declined in relative terms, but not in absolute terms. The countries, starting at lower ICT levels, are not adopting ICT faster than the leaders. Continental region-wise analysis also shows that the catch-up is maximum for already developed countries, and minimum for countries in African and Oceania continental regions. 相似文献
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方振富 《中国科学院研究生院学报》1987,25(4):307-313
1. The distribution of Salix species among the continents. There are about
526 species of Salix in the world, most of which are distributed in the Northern Hemisphere
with only a few species in the Southern Hemisphere. In Asia, there are about 375 species, mak-
ing up 71.29 percent of the total in the world, including 328 endemics; in Europe, about 114
species, 21.67 percent with 73 endemics; in North America, about 91 species, 17.3 percent with
71 endemics; in Africa, about 8 species, 1.5 percent, with 6 endemics. Only one species occurs
in South America. Asia, Europe and North America have 8 species in common (excluding 4
cultivated species). There are 34 common species between Asia and Europe, 14 both between
Europe and North America and between Asia and North America, 2 between Asia and Africa.
Acording to the Continental Drift Theory, the natural circumstances which promoted speciation
and protected newly originated and old species were created by the orogenic movement of the
Himalayas in the middle and late Tertiary. Besides, the air temperature was a little higher in
Asia than in Europe and North America (except its west part) and the dominant glaciers were
mountainous in Asia during the glacial epoch in the Quaternary Period. Then willows of Eu-
rope moved southwards to Asia. During the interglacial period they moved in opposite direc-
tion. Such a to-and-fro willow migration between Asia and Europe and between and North
America occurred so often that it resulted in the diversity of willow species in Asia. Those
species of willows common among the continents belong to the Arctic flora.
2. The multistaminal willows are of the primitive group in Salix. Asia has 28 species of
multistaminal willows, but Europe has only one which is also found in Asia. These 28 species
are divided into two groups, “northern type” and “southern type”, according to morphology of
the ovary. The boundary between the two forms in distribution is at 40°N. The multistami-
nal willows from south Asia, Africa and South America are very similar to each other and
may have mutually communicated between these continents in the Middle or Late Cretaceous
Period. The southern type willows in south Asia are similar to the North American multista-
minal willows but a few species. The Asian southern type willows spreaded all over the conti-
nents of Europe, Asia and North America through the communication between them before the
Quaternany Period. Nevertheless, it is possible that the willows growing in North America
immigranted through the middle America from South America. The Asian northern type mul-
tistaminal willows may have originated during the ice period.
The multistaminal willows are more closed to populars in features of sexual organs. They
are more primitive than the willows with 1-3 stamens and the most primitive ones in the ge-
nus.
3. The center of origin and development of willows Based on the above discussion it is re-
asonable to say that the region between 20°-40°N in East Asia is the center of the origin and
differentiation of multistaminal willows. It covers Southern and Southwestern China and nor-
thern Indo-China Pennisula. 相似文献
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Technological dynamism in Asia 总被引：1，自引：0，他引：1
We analyze innovation in emerging and newly industrialized economies over the past 30 years, with the emphasis being on Asian economies. We use US patent data to study how the innovative capabilities of Taiwan, South Korea, Hong Kong and Singapore have expanded in relation to emerging economies in Asia and Latin America. We then carry out a sector-level analysis of innovation for South Korea, Taiwan, Singapore, Hong Kong, India and China. We also study the relative importance of foreign multinationals, business groups, individuals, domestic firms and research institutes in innovation. Finally, we study the overall concentration of innovative activity in Asian economies. 相似文献
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相关多元化与归核化的研究综述 总被引：10，自引：0，他引：10
随着美国企业在20世纪80年代后期轰轰烈烈的归核化运动的开展，归核化在西方学术界已经得到了广泛的关注。随后，欧洲、南美、东南亚和日本等地都掀起了回归主业的浪潮。综合了已有的国内外学术界对多元化和归核化的相关研究以及我国目前的发展现状，提出了我国企业在战略选择上的一些建议。 相似文献
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本文分别从产业结构优化、企业竞争力培育、产品高端化三个维度分析美国、日本、韩国、德国、北欧等发达国家和地区现代产业体系的架构体系与特征,总结发达国家现代产业体系演进进程和共同规律,对构建符合河北实际的现代产业体系提供借鉴。 相似文献
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Deepak Kumar Pasupula P. S. Reddy 《Indian journal of clinical biochemistry : IJCB》2014,29(4):479-484
To determine the normal range of Hemoglobin and cutoff values in healthy adults of Southern India, blood samples were analyzed for parameters of RBC and iron metabolism in 177 male and 203 female medical students. The data were compared with the American white population (NHANES III) and the WHO criteria for detection of anemia. The mean values for hemoglobin and hematocrit in male students differed minimally from American white males. However, values for parameters of iron metabolism were lower except total iron binding capacity (TIBC) which was higher. In female students, hemoglobin, hematocrit and parameters of iron metabolism were lower than American white females, except TIBC which was higher. Lower 5th percentile cutoff point (Mean − 1.645 SD) in males and females were 13.5 and 10 g/dl respectively. In conclusion, South Indian adult males have Hb values similar to American male adults, but South Indian females have considerably lower Hb levels than American females, raising the questions about appropriateness of WHO or US criteria for detection of anemia in Indian females. 相似文献
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Since it was introduced into Europe from South America by the Jesuits at the beginning of the 17th century, quinine has been one of the most effective drugs for the treatment of malaria. During this century a number of synthetic antimalarial drugs have been introduced but while these have had considerable success their extensive and sometimes haphazard use, often as an alternative to vector control, has created serious resistance problems. 相似文献
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全球91%的智能网联汽车专利掌握在日本、中国大陆、美国、韩国、德国手中,通过聚焦分析主要国家(地区)智能网联汽车技术发展态势,为我国在该领域的技术发展提供参考。综合应用Derwent Innovation、Derwent Data Analyzer、Innography等专利检索平台和分析工具,在明确智能网联汽车关键技术基础上构建检索策略,从申请趋势、技术生命周期、技术领域、主要专利权人、专利价值等视角,对全球智能网联汽车专利进行宏观分析,对主要国家(地区)专利进行比较研究。 相似文献