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101.
102.
酶水解小麦秸秆纤维素研究 总被引:1,自引:0,他引:1
对小麦秸秆纤维素的生物降解进行了探索。考察了酶的用量、底物浓度、pH值及其在线控制、反应时间诸因素对酶解反应的影响。实验结果表明最适宜反应条件为:酶/小麦秸秆=0 04、秸秆浓度为5%、反应时间3天、在线控制pH值4 8,在此条件下,酶解率可达60 4%。 相似文献
103.
Pretreatment of Corn Stalk by Steam Explosion 总被引:3,自引:0,他引:3
A steam explosion pretreatment,which is one of the best ways of pretreating plant stalk,is applied at various severities to corn stalk.It could effectively modify the super-molecular structure of com stalk and defibrat-ing corn stalk into individual components.The relationship between yield of reducing sugar and the operating con-ditions,including temperature,pressure of steam explosion pretreatment and acidity,is also established.Experi-mental results prove that the steam explosion substantially increases the yidld of reducing sugar,and the optimal condition for steam explosion is as follows;the pressure is 2.0MPa,the pressure-retaining time 300s,the initial acid concentration 1%and the acid treatment time 24h. 相似文献
104.
玉米变性淀粉压裂液稠化剂的研制 总被引:4,自引:0,他引:4
对玉米淀粉经化学和物理变性制得变性淀粉。将该变性淀粉与少量植物胶XDF复配制成压裂液稠化剂。并对该稠化剂的理化性能、用量、复配比例以及压裂液的配方、性能和影响凝胶的因素进行了研究。结果表明:用该稠化剂配成的压裂液粘度高、流变性好、摩擦阻力小、易破胶、低残渣、低伤害,是一种适用于80℃以下低温的优良压裂液。 相似文献
105.
对一株里氏木霉突变株液体发酵产纤维素酶的培养条件进行了优化,确定培养基的最适碳源和氮源种类及添加量(g/L)分别为:小麦秸秆15,小麦麸皮5,尿素10~15,(NH4)2SO412,NH4NO35;最适培养条件为:接种种龄72h,接种孢子悬液浓度2×107个/mL,培养温度30~32℃,pH值5 0,培养时间144h,摇瓶转速180r/min,装液量75mL/250mL三角瓶.在培养里氏木霉的培养基中同时接种黑曲霉(二者孢子数比为60∶1)进行混合培养,β 葡萄糖苷酶的产量是对照试验的2 9倍,明显改善了纤维素酶系的比例,提高了它们之间的协同作用效果,在最适培养条件下,粗酶液的β 葡萄糖苷糖活和FPA酶活分别达到127 6U/mL和84 8U/mL. 相似文献
106.
107.
曲贵伟 《辽东学院学报(自然科学版)》2004,11(2):45-47
通过连续三年的施用生物有机肥料,结果表明:土壤的物理性质得到一定的改善,其中pH下降达3.53~5.39%,容重则提高0.37%~4.97%;产量显著提高,可达2.02%~80.3%。同有机无机混合肥料、有机肥料及化学肥料相比,具有明显优势。 相似文献
108.
In this study, the potential of organic acids (formic acid, acetic acid) in a catalytical and mechanocatalytic conversion of lignocellulosic barley straw to valuable sugars is explored using sulfuric acid as a reference. Acid-catalyzed hydrolysis has been carried out with acid-impregnated samples as well as unmodified barley straw. In the mechanocatalytical approach, pretreatment consists of impregnation with the acid catalyst and mechanical treatment by ball milling following chemical hydrolysis. Straw samples and residues were analyzed by Fourier transform infrared spectrometry (FT-IR) whereas hydrolysate analysis was based on total reducing sugar (TRS) determination following the DNS method and capillary electrophoresis (CE) analysis. The results indicated that acetic acid and formic acid are rather mild acids yielding low TRS levels compared to the reference acid. Mechanocatalytical pretreatment slightly increased TRS yields, but not significantly. Strikingly, sulfuric acid showed an efficient conversion efficiency yielding almost 45% of TRS. Furthermore, this study provided evidence for the acetylation of straw components when acetic acid was used as catalyst. Alkali hydrolysis induced the de-esterification, but revealed no significant increase of TRS yields. 相似文献
109.
Study of the impact of a new hurdle technology composed of electro‐activated solution and low heat treatment on the canned pea and corn quality and microbial safety 下载免费PDF全文
Viacheslav Liato Steve Labrie Marzouk Benali Mohammed Aïder 《International Journal of Food Science & Technology》2016,51(1):180-193
The objective of this work was to evaluate the quality of sterilised canned pea and corn in electro‐activated brine solutions at moderate temperatures. The lowest change in vitamin C was associated with the lowest heat treatment, while the short treatment time resulted in significant changes in texture and colour of vegetables. Best texture profile was obtained with the acid electro‐activated brine solution for pea and corn. The neutral electro‐activated brine solution resulted in a less firm texture for pea and corn. The green colour and brightness of canned pea were higher when neutral solution was used (a* = ?8.4 ± 0.3) than for the acidic one (a* = ?3.7 ± 0.6). The yellowness of corn was better with the neutral electro‐activated brine solution (b* = 36.32 ± 1.24) than with the acidic one (b* = 28.44 ± 2.39). Thirty‐three percent decrease of energy consumption was obtained using the electro‐activation technology. 相似文献
110.
In this study, the structural factors controlling the enzymatic saccharification of rice straw cellulose were examined by preparing structure-modified rice straw samples such as dewaxed, alkali-treated, oxidized, and swollen rice straw. It was found that the initial enzymatic saccharification rate of the various structure-modified samples was largely controlled by the initial cellulose surface area of the cellulose unit. Although the presence of lignin limited the cellulose surface area, there was no strong relationship between the lignin content and the initial reaction. On the other hand, the long-term enzymatic saccharification of rice straw cellulose highly depended on the lignin removal rate (lignin content). It was also found that silica is not a crucial factor in controlling the enzymatic saccharification. 相似文献