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91.
92.
Rivard C. J. Himmel M. E. Vinzant T. B. Adney W. S. Wyman C. E. Grohmann K. 《Applied biochemistry and biotechnology》1989,(1):461-478
Economic evaluations of the capital costs for anaerobic digestion systems for gas production show that the reactor is a significant
cost component. The successful application of high solids digestion of processed MSW (e.g., greater than 10% solids within
the digester) would allow a decrease in reactor volume with maintenance of relatively high gas production rates. However,
high solids slurries do not mix well in conventional stirred tank reactors. A horizontal shaft, hydraulically driven reactor
was designed and fabricated to test the anaerobic digestion of high solids concentrations. Digester performance was evaluated
as a function of experimental parameters such as nutrient requirements, feeding rates, pH control, and agitator design/ rotation
speed; horsepower of mixing was also evaluated for the reactor. Several startup protocols were examined to obtain a biologically
stable anaerobic fermentation at high solids levels. 相似文献
93.
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The solubility of glycine,
-alanine,
-valine,
-leucine, and
-isoleucine in water was measured at 298.15 K and pressures up to 400 MPa. The standard deviation of the logarithm of the solubility is 0.001–0.003, equal to or better than the accuracy of atmospheric pressure measurement in the literature (0.001–0.05). A variety of solubility phenomena were observed. The solubility of glycine decreased with increasing pressure, whereas that of
-alanine increased. The
-valine and
-isoleucine have a solubility maximum at around 100 MPa, and
-leucine seems to exhibit a solid-phase phase transition at around 200 MPa. Pressure coefficient of the solubilities at 0.10 MPa is compared with that thermodynamically estimated in reference to aqueous density measurements of glycine and
-alanine at 298.15 K and 0.10 MPa, supporting a reliability of our high-pressure measurements. 相似文献
96.
在实验室固定床反应装置上,选用Mo-Ni-P/Si-Al工业催化剂,对精煤液化中油进行了加氢裂化制取喷气燃料的实验。考察了反应温度、空速对芳烃加氢转化及产品馏分分布的影响。通过加氢裂化,降低了油品芳烃含量,提高了喷气燃料馏分的收率。在总压为15MPa,反应温度为350—360℃,空速为0.8—1.0h~(-1)条件下,获得了芳烃含量低于10w%的低结晶点的优质喷气燃料产品。并对煤液化中油制取的喷气燃料的组成和性质进行了分析和评价。 相似文献
97.
98.
构筑了MgO部分稳定的ZrO2基固体电解质电化学电池测量EAF的实验装置,测定了Sm2CuO4的标准Gibbs生成自由能。结果表明化合物RE2CuO23(RE=La,Nd,Sm,Eu)随着镧系元素离子半径减小,热力学稳定性下降,并用晶体场理论解释了这一规律。 相似文献
99.
煤炭液化复合铁系催化剂的研究 总被引:1,自引:0,他引:1
用微型高压釜,以杂酚油为溶剂,在反应温度400℃,氢初压6.08MPa,反应时间30分钟的条件下,研究了多种含铁矿物质、复合铁系催化剂对煤炭液化的催化效果。并用高压DTA技术进一步证实了复合铁系催化剂的良好液化加氢活性。 相似文献
100.
Human serum is routinely measured for total calcium content in clinical studies. A definitive high-accuracy and low-uncertainty method is required for reference measurements to underpin medical diagnoses. This study presents a novel octopole collision cell ICP-MS, high-accuracy, methodology and comparison of that technique with double-focusing sector field ICP-MS and an ICP-OES method. Double-matched isotope dilution mass spectrometry (IDMS) was employed for ICP-MS techniques and an exact matching bracketing technique using scandium as an internal standard was used for ICP-OES analysis. Medium resolution mode was utilised for double-focusing sector field ICP-MS analysis to resolve the dominant interferences on the 44Ca/42Ca isotope pair. Hydrogen reaction gas was employed to chemically resolve a number of polyatomic interferences predominantly through charge transfer reactions in the octopole collision cell. Comparison data presented for NIST CRM 909b human serum analysis from all three techniques demonstrates highest accuracy (99.6%) and lowest uncertainty (1.1%) for octopole collision cell ICP-MS. Data from ICP-OES using a non-IDMS technique produces comparably accurate data and low-uncertainties. The much higher total expanded uncertainties for double-focusing sector field ICP-MS compared with octopole collision cell data are explained by lower precision on the measurement of the 44Ca/42Ca isotope ratio. Data for octopole collision cell ICP-MS submitted for an international blind trial comparison (CCQM K-14) demonstrated excellent agreement with the mean of all participants with a low expanded uncertainty. 相似文献