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大学生农村创业基地建设的初步研究——以凤阳县大学生创业基地为例 总被引：2，自引：0，他引：2
大学生创业基地是大学生创业理论联系实践的重要环节,是沟通学生、学校和社会的桥梁。本文通过对凤阳县大学生创业基地的实证研究,介绍了创业基地的形成、发展,分析了创业基地存在的问题,并尝试提出相应的解决对策,以促进相关深入研究。 相似文献
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乙烯利浸种对聚乙二醇胁迫下玉米种子萌发的影响 总被引：2，自引：1，他引：1
为了优选出能使玉米种子在干旱胁迫下最佳萌发的乙烯利浸种浓度,用0、100、200、400、800 mg/L的乙烯利对玉米（‘三北2号’）种子浸种24 h,再分别用0%、5%、10%、15%的聚乙二醇(PEG6000)模拟干旱处理,测定20个双重胁迫处理组合下玉米种子发芽率、幼苗长度、MDA含量、CAT活性和POD活性,并运用方差分析和多重比较方法进行差异显著性检验。结果表明：（1）100~800 mg/L的乙烯利都能提高PEG6000胁迫下玉米种子的发芽率和幼苗长度,同时降低MDA含量,增强POD和CAT活性。（2）各指标在200 mg/L乙烯利浸种时与相同PEG水平下0 mg/L乙烯利处理有显著差异(P<0.05)。200 mg/L乙烯利浸种能显著缓解玉米幼苗在5%~15% PEG6000模拟下的干旱胁迫。 相似文献
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在福州与龙岩2个环境下,以烤烟品种‘台烟7号’与白肋烟品种‘白肋21’为亲本构建的127个F2:3家系为材料,对株高、叶长、叶宽、叶片数、分枝数、生育期和茎叶夹角7个性状进行遗传分析。结果表明：2种环境条件下,F2:3家系大部分性状分离明显,且基本符合正态分布,为多基因控制的数量性状,是一个较为理想的QTL作图群体。F2:3家系内各性状都存在不同程度的差异,分枝数变异系数最大,叶长、生育期变异系数最小,表明受环境影响较大。由各性状之间的相关分析得出：在2种环境下,21对性状中均有13对达到极显著水平,其中大部分性状相关系数均大于0.3,说明F2:3群体主要产量性状间具有复杂的相关关系。 相似文献
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苏浙沪休闲渔业发展比较研究 总被引：2，自引：1，他引：1
简述江苏、浙江和上海休闲渔业的发展背景及相关研究成果。提出长三角地区休闲渔业发展的3项动因,一是市场需求促使农业休闲旅游成为国家战略选择,二是全国范围内渔业产业结构在调整中得到优化,三是地方政府加大了投入力度。提炼并详细论述了苏浙沪三地不同的休闲渔业发展模式。通过比较指出,不同模式的形成使三地休闲渔业在发展理念、游客分布、经营主体等方面存在差异。最后提出发展建议,认为建立长三角休闲渔业战略联盟、统一行业规范标准、拓宽开发渠道、推广垂钓竞技、挖掘渔业文化、注重生态资源保护,将利于三地休闲渔业进一步发展。 相似文献
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贵州黑马羊生长发育研究 总被引：1，自引：1，他引：0
为了了解贵州黑马羊生长发育特点,为羔羊培育、肉羊育肥、草场监测、饲养管理提供参考。采用实际观察、试验测定和横纵向比较等方法对黑马羊的生长发育、产肉性能进行分析。结果表明：贵州黑马羊6月龄公、母羊体重为(18.46±3.29) kg和(17.35±3.23) kg,均显著高于贵州黑山羊(P<0.05);周岁公、母羊体重为(29.39±5.51) kg和(24.53±5.67) kg,成年公、母羊体重为(40.08±7.73) kg和(34.90±6.56) kg,周岁和成年公、母羊体重均极显著高于贵州黑山羊 (P<0.01)。周岁公羊、成年羯羊屠宰率为48.50%、51.61%。公、母羊生长速度0—3月龄最快,日增重为129.56、126.33 g;0—6月龄次之,日增重为88.12、84.59 g;其他月龄段逐渐下降。已探索出贵州黑马羊的生长发育规律,生长速度胜过贵州黑山羊,且有其特有的外表特征、遗传性稳定,有必要加快新品种的培育。 相似文献
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土壤磷的动态积累及土壤有效磷的产量效应 总被引：2，自引：0，他引：2
采用田间磷肥试验和田间定位监测相结合的方法,研究了不同磷用量下土壤磷素的动态积累对土壤有效磷(Olsen-P)在大白菜和辣椒上的产量反应,探讨用土壤有效磷反映土壤供磷能力和作为推荐磷肥用量的依据。结果表明:磷肥和土壤Olsen-P在白菜和辣椒上的产量效应均符合一元二次式。土壤磷素收支平衡33.7%~680.4%,土壤Olsen-P占土壤磷积累量的17.7%~28.9%。0~20 cm日光温室土壤磷素收支平衡124.1%~293.6%,0~20 cm土壤Olsen-P的年均积累量为23.1~32.2 mg/kg,土壤Olsen-P占土壤磷积累量的16.6%~24.2%。20~100 cm日光温室土壤Olsen-P的增加量随着施磷时间的延长而逐渐增加。土壤Olsen-P在植物上的产量效应符合一元二次式。农田磷的积累量与土壤Olsen-P的增加量呈直线正相关,土壤Olsen-P的增加量占农田积累磷的17.7%~28.9%。土壤供磷能力和磷素平衡是确定磷肥用量的重要参数。 相似文献
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为了解锡林郭勒草地土壤主要养分的分布及变化规律,利用2006—2011年土壤主要养分测定资料,应用一元线性回归、线性倾向估计、相关分析等数理统计方法进行分析。结果表明：锡林郭勒草地土壤主要养分有机质、全氮、全磷、全钾含量分别为22.371 g/kg、1.053 g/kg、0.36 g/kg、23.737 g/kg,逐层0~5,5~10,10~20,20~30 cm含量变化趋势均随着深度的增加而递减,平均递减率分别为-0.361、-0.031、-0.004、-0.051 (g/kg)/cm,且存在一定的相关性。逐年变化趋势有机质呈显著上升趋势,趋势相关系数为0.8087,通过0.05显著性水平检验,上升速率为1.457 (g/kg)/年。全钾呈显著下降趋势,趋势相关系数为-0.903,通过0.001显著性水平检验,下降速率为2.4806 (g/kg)/年。全氮、全磷变化趋势不显著,变化速率分别为0.015、0.012 (g/kg)/年,不同草原类型土壤养分变化与总体存在一定差异。 相似文献
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磷是植物生长和发育所必需的大量营养元素之一。由于自然或者人为原因,土壤中有效磷的分布严重不均。在长期的进化过程中,植物逐渐形成了复杂的响应机制以维持体内的磷的稳态。植物可以通过改变根系构型、形成菌根共生体、诱导高亲和磷酸盐转运体、诱导分泌有机酸和酸性磷酸酶等多种途径,提高植物吸收和利用磷的效率。目前关于植物对低磷胁迫信号转导和适应机制的研究已比较深入,但是关于植物如何在磷充足、磷富余情况下避免磷毒害方面的研究还尚未明确。为了增加水稻的产量,农民往往施加了过量的化肥,这不仅造成了环境污染,也造成了部分耕地中磷的过量积累。植物也具有精细的调控机制,避免高磷毒害。本研究主要针对植物防止过量积累磷的分子机制进行综述,并对该领域未来的研究重点进行了展望。 相似文献
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David Stuligross 《Asia Pacific viewpoint》2008,49(1):83-97
Abstract: Jharkhand is at the centre of India's struggles to define ‘the environment’ and ‘economically relevant natural resources’. Although cultural labels are applied by leaders who seek influence in these struggles as well as by many of those people who listen, an ethnonational analytic frame does not help answer the questions: How, why and when has the political idea of environment changed in India? When and why has the Jharkhand movement chosen violent tactics? When and why has the Jharkhand statehood movement realised electoral success? Or, why was Jharkhand state formed? To address such questions, a long range historical‐institutional approach is much more fruitful. 相似文献
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Gerry Van Klinken 《Asia Pacific viewpoint》2008,49(1):35-47
Abstract: West Kalimantan (West Borneo) has a history of violent communal conflict.1 It also has extensive forests that have been looted for decades. The argument will be that these two are linked, but not by the grievances of the forest dwellers. Except in its first few days, the two main episodes of 1997 and 1999 were not driven mainly by grievances among marginal groups. Rather, explanations based on the ‘resource curse’ carry more weight. These focus attention on the contested nature of the state, rather than on rebellious activities of marginal groups. When state institutions were thrown into disarray by the sudden resignation of President Suharto in 1998, Dayak militants already close to state power rewrote the rules of local politics by demonstratively ‘cleansing’ certain areas of an unpopular immigrant minority. This theatrical manoeuvre impressed political rivals sufficiently to allow Dayaks to gain control over several timber‐rich districts, which had a thriving black economy. Malays later imitated these techniques to stem the tide. 相似文献
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不同蔬菜对重金属汞、铬、砷、镉、铅积累效应的研究 总被引：3，自引：1，他引：2
为了对辽宁省葫芦岛龙岗区蔬菜生产基地蔬菜生产结构的调整提供科学的参考,采用原子吸收的方法,对该生产基地的土壤与蔬菜中重金属(Hg、Cr、As、Cd、Pb)的含量进行检测。结果表明：该蔬菜基地土壤中Hg的含量平均为0.42 mg/kg,Cr的含量平均为52.20 mg/kg,As的含量平均为34.92 mg/kg,Cd的平均含量为0.93 mg/kg,Pb的含量平均为98.49 mg/kg,说明该地区的土壤中重金属含量基本符合农业生产的要求;该蔬菜基地蔬菜中Hg的含量平均为0.92 μg/kg,Cr的含量平均为120.09 μg/kg,As的含量平均为13.80 μg/kg,Pb的含量平均为94.17 μg/kg,Cd的平均含量为15.65 μg/kg,并且所测定的蔬菜样本中甘蓝在5种重金属的含量上均比其他蔬菜的含量高,但也能符合国家卫生标准。此实验可为该蔬菜区蔬菜生产结构的调整提供一定的参考。 相似文献
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Andrew P. Butcher 《Asia Pacific viewpoint》2004,45(2):255-278
Abstract: This paper considers the convergence of immigration/globalisation and education in New Zealand. The issues of immigrant students at Epsom Normal Primary School were raised nationally in 1995, and this incident serves as a useful departure point to consider some of the challenges involved in bridging the gap between immigration and education. Educational immigration is a notion used by Belich (2001) amongst others, to suggest that immigrants arrive in New Zealand in order to bypass full cost fees paid by international students. This notion, while useful, is challenged. Research undertaken in North Shore City as well as official immigration figures show the complexities of the issue: immigrant communities may be indirect recruiters of these students, but there are also an increasing number of international students becoming permanent residents. Either way, education providers face particular challenges with migrant students, not only in terms of English language abilities, but also in the lack of financial incentive migrant students give to an education provider relative to international students’ contributions. These micro issues are placed in perspective when returning to considering the transient nature of many young migrants exploring opportunities in a globalised world. 相似文献
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WEIPING WU 《Growth and change》2007,38(4):544-566
ABSTRACT Today rapidly growing economies depend more on the creation, acquisition, distribution, and use of knowledge. As such, strategies for enhancing research and innovation capabilities have come to occupy a more important position in many developing nations, including China. Already the leading production center, and often seen as China's economic locomotive, Shanghai is striving aggressively to retain its national preeminence and has launched concerted efforts to increase local innovative output. The primary purpose of this paper is to understand how state‐led efforts have fared in promoting technology innovation. By situating the city in the national and global context, the paper shows that Shanghai has gained a substantial lead in developing an innovation environment with extensive global linkages and leading research institutions. Recent efforts in building up the research and innovation capacity of the enterprise sector have begun to show progress. Although firms are enthusiastic about its future as an innovation center, Shanghai continues to face challenges of inadequate protection of intellectual property, lack of venture capital investment, and the tightening supply of highly qualified knowledge workers. 相似文献
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James Ockey 《Asia Pacific viewpoint》2005,46(2):115-127
Abstract: Many in Thailand have begun to worry about the future, when a new monarch will reign. There is fear that without the wise use of informal royal influence, Thailand may not be able to resolve future crises without major conflict. There have thus been attempts to re‐engineer the political system to increase stability, at the expense of democracy and participation. Yet, of the many achievements of King Bhumibol, perhaps the most overlooked has been his strengthening of the institutions of the monarchy. In this article, I will argue that the institutions of the monarchy have been greatly strengthened in the last four decades. Although the current monarch came to the throne with little institutional support, any future monarch will come to the throne with the assistance of large numbers of personnel, a stable budget and a council of powerful and experienced advisors. The informal role of the monarch in supporting democracy has also been shared, to some degree, with a larger and more influential privy council, and especially with its president. Consequently, future monarchical succession should see considerable continuity and stability. Such preparations make the sacrifice of democracy in pursuit of stability unnecessary and unfortunate. 相似文献
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Acid soils containing high levels of aluminum (Al) are known to severely limit plant growth on over 1.6 billion hectares worldwide.
In the United States, a gradual decline in the pH of many soils both in the Great Plains as well as the Southeast, has caused
many soils to become high in levels of free Al. This worldwide condition encouraged the analysis of wheat (Triticum aestivum L. em Thell.), triticale (X Triticosecale Wittmack), and rye (Secale cereale L.) germplasm from one of the major acid soil regions of the world (Brazil) in order to evaluate and compare the genetic
potential of Al genes for cereal improvement. The objectives were to compare Al-tolerance levels in wheats, triticales, and
ryes by measuring root elongation responses in Al-containing hydroponic nutrient solutions. Root elongation was impaired for
all species grown in 1 mg/L concentrations of Al. Rye had the longest root regrowth and Al-sensitive wheats had the shortest
root regrowth. The triticales containing a 2D(2R) substitution developed in the mid-1970s had the poorest root regrowth of
all triticale types. The newly developed advanced triticale lines (AABBRR) yet to be released for commercial production showed
the highest degree of Al tolerance of all the triticale types and approached or exceeded the levels observed in rye. This
indicated that progress is being made in improving Al-tolerance of triticale in Brazil. Of all the old and new wheat varieties
showing the highest degree of Al-tolerance, none of them were better than ‘BH 1146’ a variety that is at least 50 years old.
This indicated that over the past 50 years, although Brazilian wheat breeders have made yield improvements in wheat production,
they have not improved Al-tolerance. Rye showed a higher degree of Al-tolerance than the other cereals when tested in 1 mg/L
of Al, but as expected, some variation was noted.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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