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21.
KS Min AR Khan MK Kwon YJ Jung Z Yun Y Kiso 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(8):909-915
The performance of a laboratory‐scale anaerobic acidogenic fermenter fed with a mixture of blended kitchen food‐waste and primary sludge from a sewage treatment plant was investigated for the production of volatile fatty acids (VFA). The operating variables for acidogenic fermentation were kitchen food‐waste content (10 and 25 wt %), hydraulic retention time (HRT: 1, 3 and 5 days), temperature (ambient: 18 ± 2 °C, and mesophilic: 35 ± 2 °C) and pH (varied from 5.2 to 6.7). The experimental results indicated that effluent VFA concentrations and VFA production rates were higher at ambient temperature than at mesophilic conditions. The net amount of VFA with 10 wt % food‐waste increased up to 920 mg dm?3 with an increase of HRT, but contrasting results (a decrease of 2610 mg dm?3) were found due to the conversion of VFA into biogas in the case of 25 wt % food‐waste, which increased significantly at HRT of 3–5 days. In terms of biogas composition (CO2 and CH4), the organic matter was converted into CO2 through the oxidative pathway by facultative species at low temperature while mesophilic temperature and optimum pH (6.3–7.8) played a pivotal role in increasing rate of conversion of VFA into biogas by methanogenesis. Rates of VFA production and their conversion are dependent on the food‐waste content in the mixture. Yet, the higher concentration of food‐waste (25% compared with 10%) did not produce VFA proportionally due to the increased rate of conversion of VFA into gaseous products. The maximum VFA production rate (0.318 g VFAproduced g?1 VSfed day?1) was achieved in the 10 wt % food‐waste at ambient temperature and at a 5‐day HRT. Copyright © 2005 Society of Chemical Industry 相似文献
22.
This article reviews the steps necessary to configure and implement a complex router internetwork. This article will specifically concentrate on Cisco routers, and since they support Transmission Control Protocol/Internet Protocol (TCP/IP) natively, it will concentrate on a backbone network employing that protocol. 相似文献
23.
The effects of (+/-)-LG50643, a new N-quaternary tropinic ester of phenylcyclohexene carboxylic acid, endowed with a potent antimuscarinic activity, have been investigated on muscarinic receptor-mediated responses of the guinea-pig trachea to electrical field stimulation. An isolated preparation which allows the simultaneous measurement of tritiated acetylcholine release (prejunctional effect) and smooth muscle contraction (postjunctional effect) was used. The guinea-pig epithelium-deprived trachea was stimulated with 500 pulses (20 Hz, 1 ms, 9 V for 5 s, 30 s apart) in the presence of indomethacin (1 microM). Three successive pre- and postjunctional responses were observed. The potencies (-logEC50) of (+/-)-LG50643 for pre- and postjunctional muscarinic receptors were determined and compared with those of selective muscarinic antagonists. In addition, the affinity values of (+/-)-LG50643 for muscarinic-receptor subtypes were determined in radioligand binding experiments in cerebral cortex, heart and salivary glands of rat as target tissues for M1, M2 and M3 receptors, respectively. The results obtained in both functional and binding assays indicate (+/-)-LG50643 is a potent and selective antagonist for the M3-receptor subtype. 相似文献
24.
Seventy-three spinal cord injured patients with central cord syndrome who had undergone inpatient rehabilitation, were studied retrospectively with regard to their demographic, neurologic and functional characteristics. There were 67 males and six females with a mean age of 53.5 years. Falls was the commonest mechanism of injury (54.8%) followed by motor vehicle accidents. Eleven patients sustained cervical fractures and 41 had radiological evidence of cervical spondylosis. Seventeen patients had sensory impairment and significant spasticity was present in 14 patients. Significant improvements in the admission/discharge ASIA motor scores and Modified Barthel Index (MBI) scores (P < 0.001) were noted after rehabilitation. Ninety-two percent of patients were continent of bladder on discharge compared to 64.4% on admission. Multiple regression analysis revealed three factors associated with a better functional outcome, namely, higher admission MBI scores, absence of spasticity and younger age (P < 0.05). 相似文献
25.
AR Hart B Jestico C Antill M Taylor JF Mayberry 《Canadian Metallurgical Quarterly》1996,110(4):247-249
We studied 100 healthy children looking for lactose malabsortion. We performed in all of them the lactose breath test. We found a 10% with lactose malabsortion. There was no correlation between lactose breath test and fecal reducing substances. 相似文献
26.
HJ Berger KP van Spaendonck MW Horstink EL Buytenhuijs PW Lammers AR Cools 《Canadian Metallurgical Quarterly》1993,23(2):341-359
The pyrolytic behavior of inulin, a (2-->1)-linked fructofuranan, is described. Parallel investigations of the pyrolysis of glucose and of fructose were conducted to supplement the inulin results and to aid comparison with previous results from glucans. Effects of neutral and basic additives are emphasized. As with glucans, the addition of such additives (especially basic) increases the yields of the one-, two-, and three-carbon products (as well as of hexosaccharinolactones), while generally decreasing the yields of anhydro sugar and furan derivatives. The former products include glycolaldehyde, acetol, dihydroxy-acetone, acetic acid, formic acid, and lactic acid. Mechanistic speculations are made regarding the origins of these compounds, as well as of furan derivatives and saccharinic acid lactones. Parallels with alkaline degradation are considered. 相似文献
27.
This study examines the relationship between the first cycle of in-vitro fertilization (IVF) and subsequent cycles. The results of all IVF cycles conducted at The Hammersmith Hospital or The Royal Masonic Hospital between 1988 and 1995 were studied including those cycles where egg recovery was abandoned due to poor ovarian response. All patients underwent a standardized treatment protocol. Of those women who achieved a clinical pregnancy during their first IVF attempt, 33% achieved a pregnancy during their second cycle, statistically significantly different from the 24% of patients conceiving during a second cycle who had failed to conceive during their first. 36% of those who achieved a biochemical pregnancy in their first cycle became pregnant in their second. Age was an important factor in the success of IVF treatment, with pregnancy rates of 48% in the 20-25 year age group falling to 8% in those aged > or =41 years. Cumulative pregnancy rates were 26% after one cycle, increasing to 43% after two cycles and reached 80% after seven cycles. A previous pregnancy significantly improved a couple's probability of conception in a later IVF cycle. Overall pregnancy rates per cycle were constant for the first three attempts. Cumulative pregnancy rates continued to rise to 72% after six cycles. Thus the more cycles a couple undergo (up to six) the greater their chance of a pregnancy. 相似文献
28.
29.
This article presents data from a population-based, random-digit dialing telephone survey of 1228 employed adults in Washington State, conducted 1989 through 1990. Eighty-one percent of men and 91% of women reported work-site smoking restrictions. Employees in work sites with no-smoking policies were less likely to be current smokers; men in work sites with policies restricting smoking smoked fewer cigarettes on both workdays and nonworkdays. Forty-eight percent of male and 53% of female smokers reported reduced smoking as a result of work-site policy. Work-site smoking policies, intended to protect against smoke exposure, may also reduce employee smoking. 相似文献
30.