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1.
介绍了电镀镍污泥浸出工艺中氨回收的工艺流程、使用原材料和各单元操作,并对各单元操作的技术条件进行了理论分析和实践检验.  相似文献   
2.
Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass, hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing, andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices. At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent. At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon prices above $70,biofuels dominate all other agriculturalmitigation strategies.  相似文献   
3.
采用Wistar大鼠50只分别饮用含氟化钠150mg/L和含氟化钠150mg/L加不同剂量亚硒酸钠水.二个月后断头处死,取肺,脾作肥大细胞(MC),糖元PAS反应,DNA(Feulgen)反应观察.结果:肺,脾氟化钠(150mg/L)组肥大细胞与正常组比较,无明显变化.糖元PAS反应,DNA(Feulgen)反应减弱;氟化钠(150mg/L)加亚硒酸钠(2.0mg/L)组,肥大细胞显著增加,糖元PAS反应,DNA(Feulgen)反应程度增强.提示:硒在保护氟引起肺,脾损伤过程中,可能对肺、脾的肥大细胞增生和活化起促进作用.  相似文献   
4.
We assess the impact of a potential TTIP bilateral free trade agreement on the EU and US bio‐economies (feedstock, biofuels, by‐products, and related competing crops) and major trade partners in these markets. The analysis develops a multi‐market model that incorporates bilateral trade flows (US to EU, EU to US, and similarly with third countries) and is calibrated to the OECD‐FAO baseline for 2013–2022 to account for recent policy decisions. The major policy reforms from a TTIP involve tariff and TRQ liberalisation and their direct contractionary impact on US sugar supply, EU biofuel production, and indirect negative effect on US high fructose corn syrup (HFCS) production. EU sugar and isoglucose production expand along with US ethanol and biodiesel and oilseed crushing. EU sugar would flow to the US, US biofuels and vegetable oil to the EU. We further quantify non‐tariff measures (NTM) affecting these trade flows between the EU and the US. EU oilseed production contracts, and EU crushing expands with improving crushing margins following reduced NTM frictions. Our analysis reveals limited net welfare gains with most net benefits reaped by Brazil and not the two trading partners of the TTIP.  相似文献   
5.
Many countries are promoting biofuels as a substitute for scarce oil. This paper develops a dynamic model of land allocation between food and energy and shows how the model can be calibrated using standard optimization techniques. Some possible implications of the trade-offs between food and energy are discussed. Specifically, we show that the effect of mandates is mainly felt through increased land conversion, which increases indirect carbon emissions Crude oil prices do not decrease significantly because of leakages.  相似文献   
6.
我国细胞治疗产业发展现状研究   总被引:1,自引:0,他引:1  
王蕾 《科技和产业》2018,(11):27-29
中国在细胞治疗领域的基础研究位列世界前列,一些龙头企业正在积极进行相关技术的研发,加紧全产业链的布局,我国的细胞治疗产业正处于成功商业化和临床受益的爆发点。介绍了我国细胞治疗的市场环境、政策环境、国内外最新研究进展和我国细胞治疗行业代表企业的发展情况,提出了未来我国发展细胞治疗产业的关键挑战,并对今后的发展方向进行了展望。  相似文献   
7.
德国将生命科学界定为“引领性先进学科”,而系统生物学、计算神经科学与医学基因组学是生命科学研究的前沿学科。德国联邦政府通过系列措施大力推进上述三个领域的研发创新。文章对德国生命科学领域项目实施情况、重点领域进展和支持其研究创新政策机制特点进行了分析和归纳。  相似文献   
8.
该文结核分枝杆菌感染后,抗原提呈细胞表面Toll样受体(toll-like receptors,TLR)表达差异、抗原提呈细胞的增殖、分化以及相关信号通路作一阐述.  相似文献   
9.
在用户对系统带宽以及传输速率要求越来越严格的当下,小蜂窝技术成为解决室内和热点场景覆盖和容量问题的有效途径。为了缓解小蜂窝中切换失败率和乒乓切换率之间的矛盾,首先建立了小蜂窝网络场景下的切换模型,通过采用参考信号接收功率方案对用户终端(UE)的移动轨迹进行跟踪而达到速度估计的目的;之后,推导分析了该模型中切换失败概率、乒乓切换概率与切换触发时间、UE速度的关系;最后,采用遍历算法对切换触发时间进行优化选择。仿真结果表明,所提方案能够将切换失败概率降低到接近于零,同时将乒乓切换率降低了10%,很好地缓解了两者之间的矛盾,更适合于对乒乓切换敏感的高速移动UE。  相似文献   
10.
Statistical offices are concerned with problems of protecting confidential information when publishing data in statistical tables. One method to avoid disclosure is the method of cell suppression, in which the values of the sensitive cells in the table are suppressed from publication. To prevent the values of the sensitive cells from being calculated from the tables totals, additional suppressions are necessary. The problem of minimizing the loss of information caused by the additional suppressions is a difficult optimization problem. We present and compare the performance of some heuristics for cell suppression for general three-dimensional tables.  相似文献   
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