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1.
通过α-淀粉酶、葡萄糖淀粉酶、胰蛋白酶处理莲子浆,探索出了酶解莲子浆的最佳工艺条件.实验表明,在pH值为6.5,温度95℃下α-淀粉酶水解的最佳条件为酶与底物之比为24U/g莲子、底物浓度5%、水解时间为30min;在pH值为4.0,温度60℃下葡萄糖淀粉酶糖化的最佳条件为酶与底物之比为10000U/g莲子,底物浓度为11%,时间为11hr;在pH值为7.5,温度40℃下胰蛋白酶水解的最佳条件为酶与底物之比为16 000U/g莲子、底物浓度5%、水解时间为5hr.水解率可达56.25%,可得澄清透明的莲子原液.  相似文献   

2.
采用生物-化学联合处理方法,研究棉杆皮脱胶工艺.通过正交实验,确定了果胶酶脱胶处理的最佳工艺为果胶酶浓度12%(o.w.f),温度40℃,时间30h,pH值4.4,浴比1:30;化学脱胶处理的最佳工艺为NaOH质量浓度8 g/L,H2O2质量浓度7g/L,温度100℃,时间45min,浴比1:50.  相似文献   

3.
为提高植物染料染色重现性,采用冷冻干燥法对黄柏植物染料进行了粉末提取.将提取的黄柏染料粉末对棉针织物进行相关的对比实验,探讨了染液浓度、pH值、上染温度、处理时间、浴比等工艺参数对染色重现性的影响.实验结果证明,该方法可提高黄柏染料的染色重现性,重现性高达100%.最佳工艺参数为质量浓度10g/L,温度80℃,染色时间20min,浴比1:60.  相似文献   

4.
VFA及pH值变化对UBF退浆废水效能的影响   总被引:1,自引:0,他引:1  
重点研究VFA及pH值变化对UBF厌氧反应器处理难降解退浆废水的影响,试验结果表明,在进水COD=2656 mg/L、HRT大于9 h时,VFA与pH值逐渐趋于平稳,有沼气生产;保持比较高浓度的碳酸氢盐碱度可以保持厌氧工艺稳态运行,使反应器pH值变化较小;本试验条件下,控制进水COD/SO4 2-≥2、CD浓度小于5.3 g/L,UBF反应器处理效果最佳,且进水pH值可在8.0左右。  相似文献   

5.
牛奶纤维/棉混纺针织物的漂白工艺   总被引:1,自引:0,他引:1  
研究了双氧水质量浓度、碳酸钠质量浓度、硅酸钠质量浓度、尿素质量浓度、渗透剂质量浓度、时间、温度、浴比等因素对牛奶纤维/棉混纺针织物漂白效果的影响.根据正交实验得出较优的牛奶纤维/棉混纺针织物漂白工艺:双氧水质量浓度25g/L,碳酸钠质量浓度4g/L,渗透剂JFC质量浓度2g/L,硅酸钠质量浓度4g/L,尿素质量浓度7g/L,浴比1∶20,时间60min,温度90℃.实验结果同时表明弱碱环境下,牛奶纤维/棉混纺针织物过氧化尿素氧漂的效果优于过氧化氢氧漂的效果.  相似文献   

6.
肖顺华 《广西科学》2003,10(1):45-46,62
以A3钢为基体,在不同钼酸钠浓度、络合剂用量、pH值、温度条件下,化学镀Ni-Mo-P三元合金,探讨钼酸钠浓度、络合剂用量、pH值、温度对镀层沉积速度的影响,得出最佳工艺条件为:钼酸钠浓度0.2 g/L;柠檬酸钠浓度45 g/L;pH值9;温度90 C。  相似文献   

7.
响应面分析法优化棉针织物的国产碱性果胶酶精练工艺   总被引:4,自引:0,他引:4  
采用国产碱性果胶酶对棉针织物的精练加工进行了响应面分析法最优工艺研究.首先考察了沸水预处理对酶精练效果的影响,然后采用中心组合设计法进行试验,并用SAS统计软件进行响应面回归分析、典型分析和岭嵴分析,优选出国产碱性果胶酶精练工艺条件为:pH值9.1,温度57℃,时间1.25 h,果胶酶质量浓度1.0 g/L.验证试验表明优选工艺参数较为理想.  相似文献   

8.
采用免烫整理树脂KNITTEX FA CONC在低温条件下对棉梭织面料进行潮交联,通过对织物残留含潮率、催化剂用量、树脂用量、堆置反应时间、工作液pH值的研究,确定了免烫树脂整理棉梭织面料的最优工艺参数:织物残留含潮率7%,催化剂用量130g/L,树脂用量200g/L,堆置反应时间应在16h,pH值控制在2.0左右.相对于干态交联,经该整理工艺处理的棉梭织面料抗皱免烫效果好,甲醛含量符合国家相关法令.  相似文献   

9.
苎麻脱胶过程中木聚糖酶最佳作用条件探讨   总被引:4,自引:0,他引:4  
采用均匀试验设计方法,讨论了木聚糖酶在苎麻脱胶过程中,温度、pH值和酶浓度对其酶活力的影响.通过回归分析,得到回归方程和最适酶作用条件:当pH=9.0,酶液=51 mL(即生苎麻/g∶酶液/mL=1∶17),温度=50 ℃时,Y即残胶率是17.629%.经过微量稀碱处理后,残胶率下降到2%左右,达到纺织工业的要求.  相似文献   

10.
絮凝法处理酒厂糟液废水的研究   总被引:1,自引:1,他引:0  
介绍利用共聚型高分子絮凝剂对酒糟废液进行处理 ,处理后的糟水中悬浮物质量浓度小于0 5g/L .并探讨了聚合物的类型、加量、分子量、浓度、pH值、温度等对处理效果的影响 .经絮凝处理后的废液 ,悬浮物的浓度从 4 5g/L下降至 0 5g/L以下 ,且废液粘度大大降低  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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