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1.
秸秆生物反应堆技术是一场农业革命,它是农作物的绿色营养餐,它给农作物提供充足的二氧化碳,提高温室大棚的地温,气温,改良土壤,提高农作物的产量,改善农作物的品质。 相似文献
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植物转基因技术产业化规律探寻 总被引:1,自引:0,他引:1
20 世纪80 年代初发展起来的植物转基因技术,作为植物基因工程的核心技术,可精确改造植物,显著提高作物产量和抗逆性、改良品质性状等,同时能够极大地降低农业生产的成本,缓解不断恶化的农业生态环境,将成为21 世纪解决食物安全、改善人民健康、环境污染、能源短缺等重大社会经济问题最具潜力的技术手段,转基因农作物将占据21 世纪主要农产品的大部分市场。自1983 年第一例转基因植物面世以来,国内外植物转基因技术及其产业化飞速发展,植物转基因技术及其产业已是各国政府和跨国公司的投资重点,基因资源的发掘和占有已成为国际上的竞争制高点,转基因技术及产品的安全性仍是能否产业化的争论焦点,植物生物反应器技术已成为研究热点,而植物抗逆转基因技术仍是目前的研究难点。 相似文献
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中国稀土被推到风口浪尖既是历史的选择,也是现实的无奈从上世纪50年代将稀土元素提取列入我国第一个科技发展规划以来,在历届政府的持续努力下,我国稀土资源开采、萃取和综合利用取得了多项突破性创新,一跃成为全球成本最低、品种最全、产量最高的稀土资源供应国。从2005年以来,中国稀土产品产量占全世界的90%以上。拥有丰富稀土资源的美国、法国等被迫主动封闭其稀土矿山。与此同时,在国内也形成了"稀土原料-稀土新材料-元器件-终端产品"的全产业链,在中国本土的市场消费占据世界35%的份额。但是,由于缺乏对稀土资源开采、利用与保护的战略规划,中国稀土矿产长期处于无序开发状态,乱采滥挖造成的生 相似文献
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生物质能是以生物为载体的一种可再生能源,其原料主要有林业加工采伐剩余物及灌木、农作物秸秆、能源植物、城市和工业有机废弃物、畜禽粪便等五大类.特点足资源储量丰富、可再生性、环保性.利用形式有生物发电、燃料乙醇、生物柴油、沼气等."十五"以来,自治区科技厅积极组织实施新能源发展规划,生物质能发展较快,有些领域科研技术居全同先进水平. 相似文献
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关于中国稀土出口定价权的问题探讨 总被引:4,自引:1,他引:3
稀土作为一种不可替代的高新技术和军事战略资源,在国际贸易中占有重要地位.中国在稀土的储量、产量及出口量上都处于世界首位,但中国在世界稀土市场上却没有获得应有的定价权.这主要是由于中国企业分散经营、实行"低价竞销"以至于市场势力缺失所造成的.文章基于对中国稀土生产与贸易情况的分析,从稀土市场结构以及政策因素入手,找出了稀土贸易定价权缺失的主要原因,并从行业管理与出口管理两个角度,对此问题提出了实际可行的建议. 相似文献
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发光是稀土元素的一个主要功能,稀土是发光材料的宝库。稀土元素独特的4f电子结构使其拥有众多的能级,发光波长涵盖从真空紫外到红外,但是目前只有为数很少的跃迁被用于发光材料,大多数跃迁未被利用。稀土离子的发光4f电子在不同能级之间的跃迁(f-f跃迁和f-d跃迁),以及4f电子与配体之间发生的电荷迁移,或与基质、缺陷和陷阱之间发生的能量交换,使稀土的发光和光吸收别具一格,在发光与激光等光学材料中获得了多方面的应用。稀土元素自身的半径、光学电负性的规律也使得它们在发光材料中起到独有的作用。 相似文献
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一、世界稀土资源的储量及分布情况
稀土具有丰富优异的光、电、磁、超导、催化等性能,广泛应用于尖端科技领域和军工领域,有工业味精、新材料之母的美誉,是一种不可替代的高新技术和军事战略元素。稀土元素在地壳中并不稀少,只是分散而已。 相似文献
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秸秆生物反应堆技术的推广应用——以甘肃省平凉市为例 总被引:1,自引:0,他引:1
一、秸杆生物反应堆技术产生的背景及意义
(一)秸秆生物反应堆技术产生的背景
秸秆生物反应堆技术是山东省秸秆生物工程技术研究中心经多年试验开发出的一项农业有机栽培实用新技术。该技术的主要原理是采用生物技术将植物秸秆通过发酵反应转化为农作物所需要的二氧化碳、热量等有机和无机养料, 相似文献
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Whether lax environmental regulations are an important attractionfor mobile capital remains one of the most controversial issuesin the area of regulatory federalism. While the extant literaturedoes a nice job of estimating the effects of environmental regulationon the spatial allocation of new plant births, one neglectedarea of research is the effect that environmental regulationhas on plant relocation decisions. This paper uses an annual(198090) county level panel data set to examine the relationshipbetween air quality regulatory stringency and the destinationchoice of relocating plants. We estimate empirical models usingboth parametric and semi-nonparametric specifications. Empiricalresults from both models suggest that air quality regulationsalter significantly the destination choices of relocating plants. 相似文献
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We study the effects of environmental tax policy in a dynamic overlapping generations model of a small open economy with environmental quality incorporated as a durable consumption good. Raising the energy tax may yield an efficiency gain if agents care enough about the environment. The benefits are unevenly distributed across generations since capital ownership, and the capital loss induced by a tax increase, rises with age. A suitable egalitarian bond policy can be employed in order to ensure everybody gains to the same extent. With this additional instrument the optimal energy tax can be computed. 相似文献
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The purpose of this paper is to present information gathered in a multi‐stage sample survey of 193 rural homesteads in the Gcumisa ward of KwaZulu. The survey area was stratified into two regions of different agricultural potential. Estimates of human population, off‐farm employment, crop production expenditure, land utilization and homestead income are projected for the strata Sample observations relating to occupations, wages and cash remittances are also presented. Conclusions drawn relate primarily to the effects of yield expectations, farm size and off‐farm employment opportunities on crop production. 相似文献
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As a developing country with great regional disparities, China's rapid urbanization has had important impacts on environmental quality. In this study, the drivers‐mechanisms‐effects (DME) model is built, which shows how element agglomeration, scale growth, knowledge accumulation and industry evolution drive the environmental system to change during the urbanization process. An econometric regression model using provincial panel data is further constructed to empirically analyze the impacts of urbanization on environmental quality. It is shown that during the process of urbanization in China, element agglomeration and knowledge accumulation help to improve environmental quality but with weak positive effect, while growing urban scale and industrial structure have obvious negative effects on environmental quality. The “inverted‐U shape” (up first and then down) change in the environmental quality during China's urbanization process is obvious. It is critical that China concentrates on the transformations of both city development paths and urbanization models to reduce resource and environmental costs as much as possible. 相似文献
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China's food security has been facing several challenges, which are likely to be worsened due to climate change. The purpose of this paper is to provide an evidence on the impacts of climate change on China's agriculture, with particular attention to the market and trade responses. Using projected crop yield changes for China and its' main trading partners under changing climate, we employ an agricultural partial equilibrium model (CAPSiM) and a linked national and global equilibrium model (CAPSiM-GTAP) to assess the impacts on food production, price, trade and self-sufficiency of China. Our results show that climate change will have significant effects on crop production though with large differences among crops. Under the worst climate change scenario RCP 8.5, wheat yield in China is projected to decline by 9.4% by 2050, which is the biggest yield reduction among the crops. However, the market can also respond to the climate change, as farmers can change inputs in response to reduced yields and rising prices. As a result, production losses for most crops are dampened. For example, wheat production loss under RCP8.5 reduces to only 4.3% due to market response. The adverse impacts on crop production will be further reduced after accounting for the trade response as farmers adjust production to much higher prices in the more severely affected countries. The paper concludes that we need to learn more from farmers who optimize their production decisions in response to the market and trade signals during climate change. A major policy implication is that policymakers need to mainstream the market and trade responses into national plans for climate adaptation. 相似文献
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Based on a nationwide representative county-level dataset from China, this article empirically examines the spillover effects of air pollution from neighboring coal-fired power plants on local mortality rates due to cardiovascular and respiratory diseases. We combine data on power plants' industrial output with information on wind direction and speed to proxy for air pollution, and find that air pollution from neighboring power plants indeed has significant negative effects on local public health. The resulting treatment costs are also enormous. Our findings shed light on the necessity of intergovernmental cooperation in environmental governance. 相似文献
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This paper establishes a two-sector general equilibrium model of a small open economy to examine the impact of environmental pollution on income inequality via brain drain. The results of the equilibrium modelling show that environmental pollution in the source country can widen the income gap between skilled and unskilled workers and that brain drain caused by environmental pollution will amplify this effect; furthermore, improving the environmental quality in the recipient country will widen the skilled-unskilled income gap in the source country. Our empirical results show that deteriorating the environmental quality in the source country increases income inequality and that brain drain caused by environmental quality will amplify the effect. Our sample is divided into four sub-samples: stage of national development, level of national income, status of environmental pollution and situation of brain drain. We find that environmental pollution has different effects on income inequality via brain drain in these sub-samples. Comparing the heterogeneous components of environmental quality, we find that brain drain caused by diminished ecosystem vitality and by air quality affecting human health will widen income inequality but that other factors related to environmental quality have no significant impacts on the effect of brain drain on income inequality. The results of a robustness test support these conclusions. 相似文献
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In the past, crop insurance schemes have based indemnity payments on individual producers' yields. Insurance of individual yields does not cope efficiently with systemic risk and therefore fails in areas where crop yields are correlated across space. Area yield insurance provides an alternative and eliminates the problems of moral hazard and adverse selection associated with individual yield insurance. Area yield insurance therefore effectively copes with systemic risk. In this study, principles of area yield insurance were applied to yield data on small-scale cane growers in KwaZulu-Natal and used to calculate pure premium rates. The viability of a government-subsidised area yield insurance scheme for small-scale cane farmers was assessed in terms of affordability to the government, the farmers and private insurance companies. The empirical results obtained from this study indicate that such a scheme may pose great expense to the government and, as a result, may not be viable in South Africa. This topic needs further study, while other risk management strategies should also be considered. 相似文献
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《World development》2002,30(5):891-898
We investigate long-term productivity trends in a representative intensive rice cropping system using periodic farm level survey data spanning more than 20 years of the Green Revolution in two rice bowls of the Philippines. Estimation of production functions with year dummy variables shows substantial declines in productivity from the early 1980s to the mid-1990s. Examination of secondary data shows, however, that the survey years were unrepresentative of long-term trends and were unduly influenced by exogenous yield shocks. Correction for these effects removes the productivity decline, but shows that productivity has stagnated. A renewed emphasis on increasing crop genetic yield potential may be necessary in order to improve productivity and restore the contribution of this important farming system to poverty alleviation. 相似文献