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1.
利用微生物提高作物秸秆饲用价值的研究   总被引:2,自引:0,他引:2  
研究了微生物(乳酸菌和酵母菌混合发酵物)发酵玉米秸秆对饲用价值和奶牛饲喂效果的影响。实验处理为用筛选的微生物制剂发酵纯秸秆粉、纯秸秆粉补充氮源(豆粕粉)和碳源(玉米粉),对照为清水发酵上述原料。结果表明,作物秸秆粉经微生物发酵后有机酸(以乳酸计)含量接种后24h内大幅度提高,之后持续缓慢增加,而清水发酵的对照则没有酸积累现象;与清水发酵对照和不发酵原料相比,微生物发酵处理纯秸秆粉的粗蛋白、粗脂肪和粗纤维变化无明显差异;但发酵原料中补充碳、氮源后,微生物发酵处理的粗脂肪、维生素B含量大幅度提高,粗纤维含量显著降低,粗蛋白含量变化不明显。奶牛试验表明,与清水发酵玉米秸秆相比,微生物发酵秸秆处理产奶量增加了17.0%,乳脂率增加了1.01%。  相似文献   

2.
以液态奶为原料,以卡地干酪青霉(Penicilliumcandidum)、娄地青霉(Penicilliumroquefo)和雅致放射毛霉(Actinomucorelegans)为发酵菌种,通过测定发酵奶的游离脂肪酸(freefatacid,FFA)和游离氨基酸(freeaminoacid,FAA)含量,选出最佳发酵菌种为雅致放射毛霉.优化后的发酵条件为:雅致放射毛霉接种量(按孢子数计)1.94×10。mL,在29℃、95r/min下摇床培养4d,发酵奶中的游离脂肪酸和游离氨基酸分别为4.28%和0.37%.为了加速发酵奶中风味物质的形成,继而对脂肪酶和蛋白酶水解发酵奶进行了单因素实验和正交实验,确定最佳酶解条件为脂肪酶添加量为1.5%,无水奶油添加量为12%;蛋白酶添加量为0.15%,大豆粉添加量为6%,经55℃酶解8h后发酵奶中的游离脂肪酸、游离氨基酸和脂解率分别为11.12%、1.12%和71.6%.在此条件下对水解产物进行喷雾干燥得到的霉菌发酵型奶酪粉水分含量9.71%,蛋白质含量为29.21%,粗脂肪含量27.23%,基本与进口奶酪粉接近(水分含量7.35%,蛋白质含量35.53%,粗脂肪含量24.91%).  相似文献   

3.
蔬菜废弃物固体发酵生产饲料蛋白   总被引:10,自引:0,他引:10  
通过平板点种刺激圈及混合菌种发酵试验,确定高山娃娃菜废弃物发酵的最佳菌种组合及其最佳接种量和接种比例;通过固体发酵试验,确定了发酵培养基的最佳氮源、无机盐以及添加量;采用正交实验,确定了最佳发酵条件.结果表明:采用绿色木霉+白地霉+产朊假丝酵母为发酵菌种,加入1%的尿素、1.5%的硫酸铵、0.2%硫酸镁、0.4%的磷酸氢二钾和0.4%的过磷酸钙,采用不灭菌固体发酵工艺,并按接种10%,比例为1:2:2,蔬菜废弃物和麸皮(比例为85:15),在1L的三角瓶中投放量100g,温度27℃下发酵96h,产物蛋白质含量高达15.97%,提高了75%,营养成分平衡后,易作为饲料.  相似文献   

4.
微生物预处理可增加沼气的产量,但实验室培养菌种的成本较高,笔者采用堆放新鲜玉米秸秆的预处理法,对堆放厚度、堆放时间对微生物活性和浓度进行比较,并对堆放前后的化学成分测试比较。采用自行设计的可控性干式厌氧发酵装置,对预处理前后的玉米秸秆分别与牛粪、污泥作为接种物进行发酵,对玉米秸秆中纤维素变化及产沼气效果进行试验研究。试验结果表明:堆放20 d中层玉米秸秆酶活数值较高,且此玉米秸秆中纤维素、木质素、半纤维素的质量分数比未经处理的分别减少了5.8%、16.8%和5.7%,中温干式发酵实验中,玉米秸杆与牛粪质量为1∶1混合发酵时,堆放预处理后累计产气量比未预处理前累计产气量高24.4%;玉米秸杆与污泥质量为1∶1混合发酵时,堆放预处理后累计产气量比未预处理前累计产气量高23.27%。  相似文献   

5.
将玉米淀粉在一定条件下,以NaClO为氧化剂,NaOH为糊化剂,硼砂为粘合剂,冷法制成粘度稳定、初始粘接力强的适合瓦楞纸用玉米淀粉粘合剂.实验表明,具有最佳原料配合比为氧化剂量为40%,粉水比1:8,NaOH量为10%.  相似文献   

6.
以玉米秸秆为原料,利用纤维素酶和康宁木霉将玉米秸秆转化为可发酵糖,皮状丝孢酵母利用可发酵糖生产微生物油脂。采用正交试验,分别通过检测发酵物中还原糖含量和油脂产量,确定微生物油脂生产的最佳条件。研究结果表明:利用纤维素酶和康宁木霉处理玉米秸秆,在纤维素酶添加量为0.15%,康宁木霉接种量为10%,处理温度为26℃,处理时间为6 d的条件下,可获得还原糖含量为4.852 g/L的玉米秸秆降解物。利用皮状丝孢和酵母发酵玉米秸秆降解物生产微生物油脂,在皮状丝孢酵母接种量为9%,培养温度为26℃,培养时间为7 d的条件下,每100 g发酵产物中,可获得微生物油脂3.321 g。  相似文献   

7.
为了比较不同预处理温度对玉米秸秆暗发酵制氢性能的影响,在不同温度(40、80、120、160 ℃和200 ℃)下,采用1% H2SO4和2% NaOH两种试剂分别对玉米秸秆进行预处理,再进行中温暗发酵实验,接种物来源于以猪粪为原料的厌氧消化后的沼液。结果表明:最佳的预处理条件为80 ℃下,采用1% H2SO4对玉米秸秆预处理60 min,其单位总固体(TS)产氢量达到27 mL/g,比未预处理玉米秸秆提高了56.27%,且最大产氢速率最高可达到15.42 mL/h,比未预处理玉米秸秆的最大产氢速率提高了83.57%。玉米秸秆产氢最适宜的pH值范围为5.0~5.5,不同预处理温度会对产酸量和产酸的组分造成影响,发酵类型均为丁酸型发酵。因此,预处理温度是影响暗发酵制氢性能的一个重要因素。  相似文献   

8.
用玉米秸秆生产单细胞蛋白的菌种选育及发酵工艺   总被引:2,自引:0,他引:2  
通过硫酸常温酸解玉米秸秆粉,以正交试验优选发酵菌株、培养基组成及培养条件.实验表明,采用绿色木霉(Trichodermaviride)3.2774,(NH4)2SO425 g/L,酸解秸秆200 g/L,温度30℃,250 mL摇瓶装液量30 mL,搅拌转速200 r/min时,还原糖得率最高.以绿色木霉3.2774为出发菌株,经紫外诱变、糖化实验、稳定性实验等选育出绿色木霉NUA-051菌株,传代8次,发酵糖化率为40.7%~45.3%,具有遗传稳定性.以蛋白质得率为目标,通过5 L发酵罐正交试验确立了以酸解玉米秸秆为原料生产单细胞蛋白的发酵工艺,即酸解玉米秸秆150 g/L,木霉发酵48 h,接种酵母量2%,(NH4)2SO415 g/L,KH2PO46 g/L,MgSO4.7H2O0.4 g/L,通风量4 L/(L.min),搅拌转速500 r/min,pH值5,温度35℃.木霉发酵时间40 h,酵母发酵时间24 h,发酵总周期64 h.  相似文献   

9.
南瓜双歧发酵乳的工艺研究   总被引:1,自引:0,他引:1  
以鲜牛乳、南瓜粉为主要原料,辅以一定的辅料,进行乳酸发酵,采用正交实验选择最佳配方。结果表明:以鲜乳为原料,加入1%南瓜粉,接种3%的发酵茵种(Lb:St=1:1)和1.5%的双歧杆菌菌种,在43℃恒温条件下发酵2~3h,再置于8℃的冰箱中后发酵冷藏10~12h,所得双歧发酵乳组织均匀,口感细腻,酸甜适度,具有南瓜特有的滋味和芳香,特别适宜于糖尿病患者食用。  相似文献   

10.
以香梨果汁与啤酒大麦为主要原料,结合啤酒工艺和香槟酒工艺,通过低温发酵开发酿造型香梨果啤。研究结果表明:麦汁与梨汁混合比为1:1,主发酵温度为10℃,酒花添加量为1.3kg/m^3,发酵效果较好,其最终产品酒精度≤3.8%,固形物含量5.5%,pH值3.9,可获得理想的口感。  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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