982 resultados para Teste de raiz unitária e co-integração
Resumo:
从生物质汽化制取的燃料气,其主要成份是 CO_2、H_2、O_2、N_2、CH_4、CO 六种气体。但在不同的工艺条件下,各组份的含量差异很大。在工艺试验中,需要及时监测各种组份含量的变化,摸索最佳工艺条件,这就要求缩短分析周期。为此我们改装了一台 SP-2307色谱仪。用 Ar 作载气,只用一个热导检测器,一次进样就可完成上述六种气体的分析。改装时增加气体自动进样系统,提高了分析的准确度。
Resumo:
研究了H_2和CO在CuO-ZnO_Al_2O_3催化床中转化成H_2O和CO_2的实验装置和实验结果,论证了不同床层工作温度、系统压力、杂质浓度、流量及露点温度等因素对氧化铜床工作性能的影响;测得了H_2和CO在CuO-ZnO-Al_2O_3床上的转化特性曲线等变化规律,获得了转化容量、工作周期和转化效率等实验数据,确定了最佳运行参数。结果表明,使用CuO_ZnO-Al_2O_3床可使净化后的H_2和CO的体积分数都小于2×l0 ̄(-6),满足高温气冷堆的净化要求。为高温气冷堆中氧化铜床装置提供了可靠的设计数据。
Resumo:
Numerical analysis was used to study the deposition and burning characteristics of combining co-combustion with slagging combustion technologies in this paper. The pyrolysis and burning kinetic models of different fuels were implanted into the WBSF-PCC2 (wall burning and slag flow in pulverized co-combustion) computation code, and then the slagging and co-combustion characteristicsespecially the wall burning mechanism of different solid fuels and their effects on the whole burning behavior in the cylindrical combustor at different mixing ratios under the condition of keeping the heat input samewere simulated numerically. The results showed that adding wood powder at 25% mass fraction can increase the temperature at the initial stage of combustion, which is helpful to utilize the front space of the combustor. Adding wood powder at a 25% mass fraction can increase the reaction rate at the initial combustion stage; also, the coal ignitability is improved, and the burnout efficiency is enhanced by about 5% of suspension and deposition particles, which is helpful for coal particles to burn entirely and for combustion devices to minimize their dimensions or sizes. The results also showed that adding wood powder at a proper ratio is helpful to keep the combustion stability, not only because of the enhancement for the burning characteristics, but also because the running slag layer structure can be changed more continuously, which is very important for avoiding the abnormal slag accumulation in the slagging combustor. The theoretic analysis in this paper proves that unification of co-combustion and slagging combustion technologies is feasible, though more comprehensive and rigorous research is needed.
Resumo:
Microporous HZSM-5 zeolite and mesoporous SiO2 supported Ru-Co catalysts of various Ru adding amounts were prepared and evaluated for Fischer-Tropsch synthesis (FTS) of gasoline-range hydrocarbons (C-5-C-12). The tailor-made Ru-Co/SiO2/HZSM-5 catalysts possessed both micro- and mesopores, which accelerated hydrocracking/hydroisomerization of long-chain products and provided quick mass transfer channels respectively during FTS. In the same time. Ru increased Cor reduction degree by hydrogen spillover, thus CO conversion of 62.8% and gasoline-range hydrocarbon selectivity of 47%, including more than 14% isoparaffins, were achieved simultaneously when Ru content was optimized at 1 wt% in Ru-Co/SiO2/HZSM-5 catalyst.
Resumo:
Tb/Yb共掺的石英光纤的上转换绿光发光研究,研究了最佳浓度配比和发光机理。
Resumo:
合成甲醇铜系催化剂是广泛用于工业反应的高活性催化剂。但对含硫气体十分敏感,易硫中毒。本论文通过常压、220 ℃反应温度下硫中毒对催化活性、反应物吸附性质、催化剂表面组成与体相结构、孔分布的影响探讨了铜系催化剂硫中毒机理。同时通过考察CO、H_2在米中毒铜系催化剂上咐附、脱附、程脱及竞争吸附的性质,探讨了CO、H_2吸附机理。得到以下结果。常压下,铜系催化剂遇含硫气体引起不可逆中毒。当硫浓度较低时,H_2S占据了铜活性中心,使CO不能在该吸附中心吸附,造成失活。由于H_2S吸附引起催化剂表面铜晶相冲长也是失活的直接原因。中毒时,硫并非均匀吸附,而主要是吸附在50~80A孔内。H_2S浓度较高时,硫与催化剂反应形成硫化物是失活的主要原因。H_2在铜系催化剂上的吸附当吸附温度为225 ℃时可分为两部分,可逆吸附与不可逆吸附。可逆吸附中心属铜吸附中心,不可逆吸附中心是H_2与部分吸附的CO共同的竞争的咐附中心。CO在该温度下的可逆吸附发生在催化剂铜活性表面上。
Resumo:
钙钛石型复合氧化物由于具有许多独特的物理化学性质,如多种类型的磁性和导电性、对多种物理和化学因素的敏感性、高温下的稳定性和结构的明确易调性等长期以来一直受到固体物理、固体化学和催化科技工作者重视,本文第一部分详细总结了文献中有关这类氧化物的结构、电子状态、电磁性质、表面吸附性能、稳定性以及反应机理和催化性能等方面的重要结果。第二部分为催化剂的制备和表征方法。第三部分针对文献中研究较少的B位取代钙钛石型氧化物,系统研究了系列化合物LaM_yM'_(1-y)O_a (M, M' = Mn, Fe, Co)的固体物理化学性质和对NH3和CO氧化反应的催化性能,讨论了它们之间的关系。1. 催化剂的制备、晶体结构与光谱性质。2. LaM_yM'_(1-y)O_3(M、M' = Mn、Fe、Co)r的氧化还原性质和稳定性。3. 过渡金属离子的状态及其之间的相互作用。4. 催化剂中氧的形态。5. 氨氧化性能与固体物化性质之间的关系。6. 一氧化碳氧化与固体物化性质之间的关系。