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1.
曾佑生 《中国资源综合利用》2004,(4):23-26
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.
Introduction Anaplastic lymphoma kinase (ALK) targeting drugs provide an important option for advanced non-small cell lung cancer patients with this distinct tumor type; however, there is considerable uncertainty as to which drug provides the optimal value after crizotinib treatment. This study estimated the cost-utility of alectinib vs ceritinib from a US payer perspective.Methods A cost-utility model was developed using partition survival methods and three health states: progression-free (PF), post-progression (PP), and death. Survival data were derived from the key clinical trials (alectinib: NP28761 &; NP28673, ceritinib: ASCEND I and II). Costs included drugs, adverse events, and supportive care. Utilities were based on trial data and the literature. One-way and probabilistic sensitivity analyses (PSA) were performed to assess parameter uncertainty.Results Treatment with alectinib vs ceritinib resulted in increases of 2.55 months in the PF state, 0.44 quality adjusted life-years (QALYs), and $13,868, yielding a mean cost/QALY of $31,180. In the PSA, alectinib had a 96% probability of being cost-effective at a willingness-to-pay of $100,000/QALY. Drivers of model results were drug costs and utilities in the PF health state. The ICER ranged from $10,600–$65,000 per QALY in scenario analyses, including a sub-group analysis limited to patients with prior chemotherapy and crizotinib treatment.Conclusions Treatment with alectinib in ALK?+?crizotinib-treated patients increased time progression-free and QALYs vs ceritinib. The marginal cost increase was driven by longer treatment durations with alectinib. This model demonstrates that alectinib may be considered a cost-effective treatment after progression on crizotinib. 相似文献
4.
The Impact of an EU–US Transatlantic Trade and Investment Partnership Agreement on Biofuel and Feedstock Markets
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John C. Beghin Jean‐Christophe Bureau Alexandre Gohin 《Journal of Agricultural Economics》2017,68(2):321-344
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.
介绍了一种太阳能电池片胶带全自动贴付机的具体设计方案,设备在经过一段时间的试生产后达到了预期的设计效果。 相似文献
6.
自动摄像系统ICOS PVI-6能跟踪太阳能电池在丝网印刷制作正面电极的过程,研究各种印刷质量问题造成的电性能变化趋势。本试验以156mm×156mm多晶P型硅片为例,启动PVI-6系统,进行识别太阳能电池正面银电极的断线条数,当监控到断线的印刷质量问题后在生产过程中及时擦拭网版、调整印刷参数,后使用Berger分类检测系统测试试验电池片的电性能,与未使用监控系统的情况进行比较,电池片的电性能得到了明显提高。 相似文献
7.
8.
《Journal of medical economics》2013,16(1):55-62
AbstractBackground: Transfusion of blood products is often necessary for patients undergoing stem cell transplantation (SCT). The need for red cell and platelet transfusion may vary significantly depending on the type of transplantation and underlying disease.Methods: In an attempt to evaluate the need and volume of transfusions in patients undergoing SCT at University of Kansas Medical Center, the authors retrospectively evaluated the transfusion data of all patients who received SCT between 2000 and 2005.Results: A total of 138 (90%) out of 154 patients undergoing autologous SCT and 24 (43%) out of 56 patients with allogeneic SCT exhibited total hematopoietic engraftment and freedom from transfusion (FFT). Time to achieve FFT (median; range) for RBC units for autologous SCT (12; 0–183) was significantly shorter compared with allogeneic SCT (16.5; 0–373). Number of RBC units (median; range) transfused were significantly less in patients undergoing autologous SCT (4; 0–26) compared to patients undergoing allogeneic SCT (6.5; 0–54). The median cost of transfusion was significantly higher in patients undergoing allogeneic SCT (red cell: $2,015; platelet: $4,480) compared to patients undergoing autologous SCT (red cell: $1,240; platelet: $2,520). The authors recognize that this was a retrospective single-center study and practice guidelines may vary from center to center.Conclusion: Authors conclude that transfusion of blood products is an expensive but integral part of SCT, more so for allogeneic SCT than for patients undergoing autologous SCT. Total FFT is a desirable long-term goal of successful marrow transplantation. 相似文献
9.
动物对环境温度的适应,会使自身的细胞内转录和表达模式发成变化,以适合环境的变化,此时它会出现新的基因开放和新蛋白因子的合成,这总的来说是动物对自身的一种保护方式。本文从基因水平、蛋白质水平、细胞膜水平等三个方面综述了动物对环境温度适应的研究概况,并讨论了动物对环境温度适应的分子生物学机制以及在进化中的意义。 相似文献
10.
对近年来国内外生物气固体氧化物燃料电池发电领域的研究进行了归纳分析。在介绍生物气产生和氧离子型固体氧化物燃料电池产电原理的基础上,总结了固体氧化物燃料电池以生物质产出的生物气为燃料发电所涉及的电化学反应;介绍了国外研究者对该类发电过程进行的试验和模拟研究;同时,对生物气结合固体氧化物燃料电池的研究进展进行了分析。得出的结论为,生物气结合固体氧化物燃料电池进行产电具有重大的实际和环保意义。 相似文献