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101.
102.
Influence of Inoculum Source and Pre-incubation on Bio-Methane Potential of Chicken Manure and Corn Stover 总被引:1,自引:0,他引:1
Yeqing Li Lu Feng Ruihong Zhang Yanfeng He Xiaoying Liu Xiao Xiao Xinxin Ma Chang Chen Guangqing Liu 《Applied biochemistry and biotechnology》2013,171(1):117-127
In order to investigate the effects of inoculum source and pre-incubation on methane production performance of chicken manure (CM) and corn stover (CS), two sets of bio-methane potential tests using non- and pre-incubated inocula (digested sludge from a municipal wastewater treatment plant (DSMW) and digested sludge from a chicken manure treatment plant (DSCM)) were conducted at 37 °C. Modified Gompertz and first-order models were used to evaluate the kinetic parameters. The results revealed that DSMW was better than DSCM in digesting organic substrates (CM and CS), since the average ultimate methane yields were 351 mL g?1 volatile solid (VS)added for CM and 300 mL g?1 VSadded for CS when DSMW was used as inoculum, and 298 mL g?1 VSadded for CM and 218 mL g?1 VSadded for CS when DSCM was used as inoculum, respectively. Nevertheless, there was no significant difference (p?>?0.05) in the ultimate methane yields between non- and pre-incubated inoculum for digesting CM and CS, regardless of the inoculum source. However, when evaluating the kinetic parameters of anaerobic digestion, the correlation coefficient, maximal methane production rate, and hydrolysis rate constant were slightly higher using pre-incubated inoculum as compared to non-incubated inoculum. 相似文献
103.
Haibo Wang Lei Chen Xiuling Tang Yanyan Jia Guangqing Li Xiaoli Sun Aidong Wen 《Journal of chromatography. A》2013,1271(1):153-162
We have developed a series of new C10 dipeptide stationary phases via a simple and effective synthetic method. The preparation of the new phases involves the synthesis of silanes and the surface modification of silica. Chromatographic evaluations of these columns were performed using the Engelhardt, Tanaka, and Neue test mixtures. The applicability of these new stationary phases was also evaluated using a series of diagnostic probes including acids, bases or neutral compounds and several generic applications. These new C10 dipeptide stationary phases showed excellent hydrolytic stability over a wide pH range. Like other existing amide-embedded columns, these new stationary phases exhibit higher retention for polar and hydrophilic compounds and different selectivity as compared to conventional C18 columns. These new phases are compatible with 100% aqueous mobile phases, and also provide high column efficiency and good peak shapes for both acidic and basic compounds. 相似文献
104.
Let Ta,φ be a Fourier integral operator defined by the oscillatory integral■,where ■ and ■,satisfying the strong non-degenerate condition. It is shown that if ■ and ■,then Ta,? is a bounded operator from L~∞(Rn) to BMO(Rn). 相似文献
105.
Huogen Luo Wenxu Liang Chao Wei Dun Wu Xia Gao Guangqing Hu 《Molecules (Basel, Switzerland)》2022,27(12)
Contact metamorphism in coal is usually characterized by a rapid, brief, and exotherm reaction that can change the geothermal gradient. In this process, coal adjacent to the intrusive body can form thermally altered coal-based graphite (TACG). In order to further study the structural changes of TACG at different distances from the intrusive body, four TACG samples were collected in the Zhuji coal mine in the Huainan Coalfield, North China, and their vitrinite reflectance and Raman spectra were measured using polarizing microscopy and Raman spectroscopy. The results showed that: (1) affected by the temperature and stress of magmatic hydrothermal intrusion, the clay minerals in the coal seams appeared distributed in strips; the occurrence of ankerite and pyrite in the coal seams near the magmatic intrusions could be due to a late magmatic hydrothermal mineralization; (2) the Rmax − Rmin correlation for the TACG samples under study showed that thermal metamorphism was the main factor leading to the graphitization of the TACG samples, without an obvious pressure effect; (3) with the increase of the graphitization process, the D- and G-band showed some similar changes, specifically, their peak positions shifted to lower wave numbers, and the full width at half maximum (FWG and FWD) gradually decreased; the difference was that the intensity of the G-band increased, while that of the D-band decreased; (4) the graphitization degree of the TACG samples increased with the increase of the transverse size of the crystals, while the FWG and FWD values of the G- and D-band decreased; (5) in comparison to natural graphite, the TACG still presented structural defects. 相似文献