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41.
CeOx doping on a TiO-SiO supporter enhances Ag based adsorptive desulfurization for diesel 《燃料化学学报》2016,44(8):943-953
In this work, the impact of CeOx doping on a TiO2-SiO2 supporter on the Ag based adsorptive desulfurization for Chinese standard diesel was studied. The dispersion and valence states of Ce, Ti and Ag species were characterized, and the impact of Ce doping was investigated. The results indicated that Ce species and Ti species were dispersed evenly on the surface of SiO2 via a novel co-impregnation method. Following CeOx doping, the Ag species were in the form of oxides (about 5nm) instead of metallic Ag particles (about 35nm), which is due to the large amount of coordinative unsaturated sites provided by the interaction between CeOx and TiO2, as well as the oxidation-reduction property of CeOx. The Ag in the active oxide state (Ag2O2) and dispersed evenly on the supporter could interact with sulfur compounds more favorably, and therefore showed a good performance in the adsorptive desulfurization. In both static batch and dynamic breakthrough desulfurization tests, Ag-CeOx/TiO2-SiO2 was proved to be a more efficient adsorbent compared with Ag-TiO2-SiO2. It was found that the desulfurization performance of Ag-TiO2-SiO2 exhibited an excellent improvement (22.5%) after being doped with CeOx. In the static equilibrium tests, the equilibrium sulfur capacity of Ag-CeOx/TiO2-SiO2 was up to 5.38mg/g for CN-II diesel (sulfur content 952.9mg/kg) and the sulfur content of the CN-IV diesel (sulfur content 39.0mg/kg) after desulfurization was less than 10mg/kg, which could meet the CN-V standard. 相似文献
42.
《新拆迁条例》规范了房屋征收部门和房地产开发商、被征收入的拆迁补偿行为.运用演化博弈研究了城市商业性拆迁过程中开发商与被拆迁户之间行为特征,以及不同收益约束下各种均衡演化结果:开发商和被拆迁户均采取强硬策略导致群体性突发事件爆发;少数"钉子户"提出过分补偿要求迫使开发商接受;开发商采取暴力拆迁策略损害被拆迁户合法权益.进而讨论了政府部门提供外生性制度安排介入到城市商业性拆迁过程.政府部门在城市商业性拆迁事件中决策需要考虑多种因素的权衡.其中,逐步摆脱"土地财政"依赖,依法实施《新拆迁条例》禁止开发商的暴力拆迁行为,促使少数补偿标准期望值过高的"钉子户"回归理性态度,有利于双方达成理性双赢的(协商拆迁,让步同意)的演化均衡结果. 相似文献
43.
Optimal cloud use of quartic force fields: The first purely commercial cloud computing based study for rovibrational analysis of SiCH− 下载免费PDF全文
Ryan C. Fortenberry Russell Thackston 《International journal of quantum chemistry》2015,115(23):1650-1657
Commercial cloud computing (CCC) has the promise of an untold number of computing nodes available for the researcher as long as he or she has the financial means to absorb these costs and the administrative skills necessary to effectively utilize the resources. The key is finding how to maximize parallelization for a minimum of monetary and management costs. Previous work has shown that CCC resources are viable for use on large numbers of small‐to‐medium sized quantum chemical computations. Composite energy quartic force fields (QFFs) are a highly‐attractive platform for subsequent testing of CCC resources to find the proper balance between time savings of the cloud versus monetary expenditure. Use of this type of potential energy surface has lead to highly‐accurate rovibrational data in earlier work. QFFs use large numbers of stand‐alone energies that have to be computed for various molecular geometries. At each geometry, different methods and/or basis sets are used to efficiently generate accurate representations of the nuclear potential. For this initial study, the small molecular anion, SiCH? of interest in astrochemistry, is chosen for analysis as it can be done cheaply on the cloud while still providing insight into the nature of CCC usage. Additionally, no rovibrational data exists for this molecule making it the first molecule quantum chemically computed purely via CCC tools. © 2015 Wiley Periodicals, Inc. 相似文献
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ABSTRACTThe specific activities of 226Ra, 232Th and 40K of 26 samples of granite produced in Xinjiang of China were measured by a high-purity germanium detector, and their radiological hazards of radium equivalent, external hazard index, internal hazard index, absorbed dose rate, annual effective dose rate, gamma index and alpha index were evaluated. The results indicate that the overall average specific activities of 226Ra, 232Th and 40K obtained in the investigated samples are below the world’s average granite values. The average radium equivalent is within the recommended limit of 370?Bq?kg?1. The results obtained further show that the mean values of external hazard index, internal hazard index, absorbed dose rate, annual effective dose rate, gamma index and alpha index are 0.65, 0.77, 111.7?nGy?h?1, 0.55 mSv?y?1, 0.89 and 0.23, respectively. These mean values established that radiological hazards are also found to be below the international recommended values. The results are compared with granite samples from other countries or China-Taiwan province. It can be noticed that the specific activity values of granite samples produced in China are lower or similar to that of other countries or China-Taiwan province, however there are higher specific activity values for 226Ra and 232Th in individual samples, which need to provide proper radiation monitoring before use considering the long term health effect. 相似文献
45.
This study was aimed at determining the effect of high pressures in the range of 100–1000 MPa/15 min, applied in 100 MPa increments, on the coagulating and proteolytic activity of commercial coagulants produced with genetic engineering methods: Maxiren, Chymogen, Chymax and of a natural rennin preparation, Hala. The coagulating activity of Hala preparation differed compared with the other preparations, due to greater resistance to high pressures, especially in the range of 500–600 MPa. The preparations produced with genetic engineering methods lost their capability for milk protein coagulation by 500 MPa. Pressurization at 200 MPa contributed to their reduced capability for casein macroproteolysis. In contrast, an increase in Chymax, Chymogen, Maxiren and Hala preparations’ hydrolytic capability for the macroproteolysis of isoelectric casein was observed upon pressure treatment at 100 and 400 MPa and for microproteolysis after pressure treatment at 200 MPa. Storage (48 h/5°C) of the pressurized preparations had an insignificant effect on their coagulating and proteolytic activities. 相似文献
46.
Guilherme Tsuguio Tanaka Fabrício de Oliveira Ferreira Carlos Eduardo Ferreira da Silva Danilo Luiz Flumignan Jos Eduardo de Oliveira 《Journal of Chemometrics》2011,25(9):487-495
Samples of commercial gasoline, from the National Program of Fuel Quality Monitoring of the National Petroleum Agency, were collected from gas stations located in the Midwestern state of Sao Paulo, Brazil, and analyzed by several physicochemical standard methods established by ANP Resolution no. 309. Also, important information related to tampering was analyzed with the marker solvent. Statistical analysis and exploratory chemometric were employed to discriminate the presence of markers of solvents in commercial gasoline. The results showed that statistical and chemometric parameters such as atmospheric distillation temperatures T10 and T90, RON, benzene and saturated and aromatic hydrocarbons satisfactorily describe the presence of marker solvent, usually with a probability exceeding 70%. Furthermore, after optimizing the SIMCA algorithm, sensitivity in the training set with cross‐validation leave‐one‐out (83.8%) and the set of prediction (77.1%) were revealed. The proposed method will become indispensable and recommended for discriminating samples of fuels for commercial applications in routine monitoring programs and quality control. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
47.
商业银行是我国银行体系的主体,提高银行的经营效率和服务水平是当前金融改革的重点。已有的研究较多关注于银行的收益,对银行的非期望产出如呆坏账及服务水平等关注较少。本文运用多个处理非期望产出的DEA模型,对2008年中国商业银行的效率进行了评价分析。文章在改进熵DEA方法的基础上,利用指标体系对商业银行的综合效率进行了测度并对比了处于多模型条件下模型的区分度问题。研究结果显示,呆坏账、服务水平(等待时间)等非期望产出对商业银行的效率意义重大;股份制商业银行的效率普遍高于国有商业银行,因此国有商业银行的股份制改造是一个积极的方向。最后,根据实证分析的结果提出的效率改进建议对商业银行的自身发展和管理当局的改革规划都具有重要的指导意义。 相似文献
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在企业占有市场的模型分析中,运用分支理论和动力学系统理论,发现企业在等价的同一产品中对科研投资和广告宣传产品的力度进行调整时,会导致企业在一定的市场中所占有的市场份额出现分支;并随科研投资和宣传产品资金的增加,企业所占市场份额会进入混沌状态. 相似文献