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生物质流化床富氧气化的实验研究 总被引:12,自引:7,他引:12
在常压流化床装置上进行了生物质在富氧条件下定向气化的实验研究。实验主要考察了氧的当量比和氧体积分数对气化气组成、碳转化率和气体热值的影响。当量比值是与温度紧密联系的一个量,本实验主要通过调节进料量来改变它的值,随着当量比的变化(0.21~0.29),燃气成分也会改变,其中变化最大的是H2、CO。H2体积分数显著增加,CO和CH4体积分数有降低的趋势,使燃气热值降低;氧体积分数是富氧气化过程中较重要的参数,在实验研究的范围内,发现增大氧气体积分数可以提高H2体积分数及有利于调节H2/CO(体积分数)的比值。当氧气体积分数从21%提高到45%,H2体积分数从20%增加到27.7%,H2/CO(体积分数)从0.38增加到0.75,比较接近合成液体燃料的气体比值。 相似文献
995.
气相色谱法测定鱼和肉中有机磷农药残留量 总被引:10,自引:0,他引:10
采用气相色谱法测定鱼和肉中有机磷农药残留量,对国标法作了部分改进,从而使可测的有机磷农药组份增加一个甲基对硫磷,且灵敏度和分辨率均有所提高,同时使国标法中未完全分离的马拉硫磷和对硫磷得到完全分离。 相似文献
996.
Siying Lv Yinuo Gao Min Zhao Xinyu Jiang Xiaodong Li Jing Yang Sen Chen Shihai Cui 《Journal of separation science》2022,45(10):1693-1701
Recent findings unfold that biomass materials with the micro/mesoporous structure were often treated as adsorbents for organic substances. In this work, a one-step calcination method was adopted in the preparation of magnetic porous green bean biomass material. It has the properties of magnetism and porosity after the addition of Co(NO3)2 and high-temperature calcination. A variety of characterizations have been operated, including energy dispersive X-ray detector, vibrating sample magnetometer, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller analysis, and so on. It has a specific surface area of 168.1611 m2/g and a pore volume of 0.1764 cm3/g. The material was used in magnetic solid-phase extraction of three polychlorinated biphenyls: 2-chlorobiphenyl, 4-chlorobiphenyl, and 2,2,5-trichlorobiphenyl. Several factors were investigated, such as material amount, eluents, adsorption time, solution pH, salinity, and reusability. Under optimized conditions, good recoveries (90.24–93.34%) were achieved with the relative standard deviation in a range from 2.30 to 4.83%. Three real water samples (tap, river, and lake water) were tested to verify the accuracy of the method. This method can be successfully used in the analysis of some polychlorinated biphenyls congeners in water. 相似文献
997.
Native fungal biomass of fungiAbsidia orchidis, Penicillium chrysogenum, Rhizopus arrhizus, Rhizopus nigricans, and modified spruce sawdust (Picea engelmanii) sequestered metals in the following decreasing preference pb>Cd>Ni. The highest metal uptake was qmax = 351 mg Pb/gA. orchidis biomass. P.chrysogenum biomass could accumulate cadmium best at 56 mg Cd/g. The sorption of nickel was the weakest always at < 5 mg Ni/g. The spruce
sawdust was modified by crosslinking, oxidation to acidic oxoforms, and by substitution. The highest metal uptake was observed
in phosphorylated sawdust reaching qmax = 224 mg Pb/g, 56 mg Cd/g, and 26 mg Ni/g. The latter value is comparable to the value of nickel sorption by wet commercial
resin Duolite GT-73. Some improvement in metal uptake was also observed after reinforcement of fungal biomass. 相似文献
998.
Static Vickers indentation tests were performed on Homalite specimens with an intent to obtain the residual stress distribution beneath the indentation. The indented specimens were placed in a circular polariscope to view the fringe patterns corresponding to the induced residual stress. Similitude analysis was later employed to identify the functional relationship between the various parameters related to an indentation test. The analysis resulted in a unified relationship that can assist in the determination of residual stress in nontransparent materials subjected to similar geometric and loading conditions. The shear stress contours provided here can also be used as guidelines to verify constitutive models under complex three-dimensional loads. 相似文献
999.
酶免疫分析技术在农药残留分析中的应用 总被引:2,自引:0,他引:2
介绍了水、土壤和食品中农药残留的酶免疫分析技术的原理、类型及方法的开发与应用。引用文献22篇。 相似文献
1000.
Speech watermarking has become a promising solution for protecting the security of speech communication systems. We propose a speech watermarking method that uses the McAdams coefficient, which is commonly used for frequency harmonics adjustment. The embedding process was conducted, using bit-inverse shifting. We also developed a random forest classifier, using features related to frequency harmonics for blind detection. An objective evaluation was conducted to analyze the performance of our method in terms of the inaudibility and robustness requirements. The results indicate that our method satisfies the speech watermarking requirements with a 16 bps payload under normal conditions and numerous non-malicious signal processing operations, e.g., conversion to Ogg or MP4 format. 相似文献