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21.
从实验室保藏的9株黑曲霉菌株和1株宇佐美曲霉菌株中,通过初筛和复筛获得了一株高产酸性果胶酶菌株一宇佐美曲霉(Aspergillus usamii)YL-1。YL-1菌株产酶发酵条件为:29℃静置培养72h,期间在24h翻曲1次。采用单因素试验确定了该茵株固态发酵优化培养基组成为:250mL锥形瓶装发酵基料10g(麸皮8g+豆饼粉2g),食用果胶0.9g,玉米浆0.5mL,吐温-800.15%,(NH4)2SO4 2.0%,KH2PO40.4%(均相对于基料),料水比1:1,自然pH。酸性果胶酶活力最高达4831 IU/g干曲。 相似文献
22.
介绍了以酸性气体为原料,采用湿式接触法制取98.5%浓硫的酸的新工艺及其操作参数,技术要点和设备结构,并给出了不同生产工艺技术经济指标的比较结果。 相似文献
23.
介绍用戈尔膜分离技术处理硫酸、磷酸装置废水的工艺过程及操作特点。针对山东红日集团硫酸、磷酸装置废水的特点,提出中和、过滤、固-液分离工艺。运行情况表明,排水清澈透明,各项指标达到国家排放标准,可以循环使用。该处理工艺具有流程简单,占地面积小、运行成本低、操作管理方便等特点。 相似文献
24.
在酸性硫酸盐土壤未垦和已垦地上进行的磷矿粉田间试验结果表明,未垦地上直接施用磷矿粉对水稻有显著的增产作用,主要表现在促进水稻株高、分蘖数、穗数的增加上.但在已垦地上磷矿粉对水稻的增产作用不甚明显.施肥后对相关的土壤肥力状况变化也进行了报道. 相似文献
25.
Zhu Z. Y. Yates R. A. Caldwell J. D. 《Journal of the American Oil Chemists' Society》1994,71(2):189-194
Temperature programmed desorption (TPD) was used to evaluate the active sites of several filter aids that have been promoted
for use by the deep-frying industry: activated carbon, aluminas, bleaching earths, diatomaceous earth, silica and synthetic
magnesium silicate. TPD analysis determines both the total surface concentration of the active sites and the details of their
intensity distribution. A correlation analysis was made between the adsorbents' oil treatment performance and the observed
acidic/basic sites. For some of the adsorbents, the adsorption of free fatty acids and the percent change in the color of
the oil was shown to relate to the total basic sites and acid sites, respectively. The study also showed that other factors
might affect these adsorptivities. 相似文献
26.
原油中的酸性组分是天然表面活性物质,影响油/水乳状液的稳定性,相关研究对采出液破乳有重要参考价值。作者研究了原油中酸性组分对油/水乳状液破乳效果、乳状液粘度、油/水接触角、界面膜强度的影响,结果如下:随w(酸性组分)从2.25%增加到2.65%,85℃时,脱水率由81.2%降低至14%,粘度由212.3mPa·s增加到1 452mPa·s,乳状液的稳定性大幅度增加;随w(酸性组分)增加,油/水接触角减小,界面膜强度增加;虽然间隔都是0.2%,w(酸性组分)为2.25%和2.45%时,油/水接触角、单滴破裂率相差较大,但w(酸性组分)为2.45%和2.65%时相差较小。 相似文献
27.
The production of acidic α-amylase by a novel acidophilic bacterium Bacillus acidicola TSAS1 was optimized in submerged fermentation using statistical approaches. The process parameters that significantly affected α-amylase production (starch, K(2)HPO(4), inoculum size and temperature) were identified by Plackett and Burman design. The optimum levels of the significant variables as determined using central composite design of response surface methodology are starch (2.75%), K(2)HPO(4) (0.01%), inoculum size [2% (v/v) containing 1.9×10(8) CFU ml(-1)], and temperature (33°C). An overall 2.4 and 2.9-fold increase in enzyme production has been attained in batch and fed-batch fermentations in the laboratory fermentor, respectively. 相似文献
28.
钨和铼的色层分离研究 总被引:1,自引:0,他引:1
以^187W,^188W-^188Re为示踪剂,为W和Re在阴离子交换色层柱和酸性Al2O3色层柱上的吸附和解吸行为进行了系统研究,给出了W和Re的放射化学分离程序,实验结果表明,无论是阴离子交换色层柱还是酸性氧化铝层柱都可使钨,铼达到满意的分离,推荐的分离程序可用于无载体^186Re的制备。 相似文献
29.
Synthesis and evaluation of new long alkyl side chain acetamide, isoxazolidine and isoxazoline derivatives as corrosion inhibitors 总被引:3,自引:0,他引:3
2-(Alkylsulfanyl)-N-(pyridin-2-yl) acetamide derivatives were synthesized via amidation reaction of acyl chlorides bearing S atom in the long chain with 2-aminopyridine. Derivatives of isoxazolidine and isoxazoline were synthesized through 1,3-dipolar cycloaddition reactions with three different long chain alkenes containing O or S as hetero atoms and C,N-diphenyl nitrone or benzonitrile-N-oxide, respectively. Synthesized compounds were characterized with their FT-IR, 1H NMR spectra and then their physical properties and corrosion prevention efficiencies were investigated. All compounds were tested with steel coupons in acidic medium by gravimetric method, and also some of them were tested with steel stripe in paraffin based mineral oil medium via standard method. Acidic test was done with a medium concentration of 2 M HCl for 20 h at room temperature. Mineral oil was used and the test in this medium was done at 60 °C constant temperature but varying time from 42 to 63 h. The best inhibition was generally obtained at 50 ppm inhibitor concentration in the acidic medium. All tested inhibitors except two of them in oil medium also showed promising inhibition efficiencies. 相似文献
30.
The effects of marinating time (30, 60, 120 and 180 min) and acidic marinade pH (3.0, 3.2, 3.4, 3.6, 3.8, 4.0 and 4.2) on the instrumental and sensory properties of cooked Chinese-style marinated chicken were investigated. With increasing marinating time up to 180 min, a significant (P < 0.05) increase in surface redness (a∗ value) and the dark pink sensory attribute was observed, along with a corresponding decrease in lightness (L∗ value) and colour penetration. Increased marinating times of 120–180 min were found to produce more acceptable end products with increased scores for colour, aroma and flavour attributes. Marinade uptake was greater at higher marinade pH levels of 3.8, 4.0 and 4.2, with the highest marinade uptake (3.34%) recorded at pH 4.0. As changes to core meat pH were not observed, the effect of marinating time (up to 180 min) and marinade pH on the instrumental and sensory properties of Chinese-style marinated chicken were located principally at the surface of samples. Consumers considered surface colour as contributing to acceptability of marinated chicken to a greater degree compared to colour penetration. 相似文献