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1.
The catalytic wet air oxidation of aqueous solution containing 1000 ppm aniline was conducted in a trickle-bed reactor packed with a novel nanocasted Mn-Ce-oxide catalyst (surface area of 300 m2/g) prepared using SBA-15 silica as a hard template. A range of liquid hourly space velocities (5-20 h(-1)) and temperatures (110-140 degrees C) at 10 bar of oxygen were tested. The experiments were conducted to provide the intrinsic performance of the catalysts. Complete aniline conversion, 90% TOC conversion, and 80% nitrogen mineralization were achieved at 140 degrees C and 5 h(-1). Blank experiments yielded relatively low homogeneous aniline (<35%) and negligible TOC conversions. Fast deactivation of the catalysts was experienced due to leaching caused by complexation with aniline. Acidification of the solution with HCI (molar HCI to aniline ratio of 1.2) was necessary to avoid colloidization and leaching of the nanoparticulate catalyst components. The catalyst displayed stable performance for over 200 h on stream.  相似文献   

2.
通过比较不同菌种麸曲酯化酶合成乳酸乙酯的能力,筛选适用于白酒生产的乳酸乙酯酯化酶高产菌株。利用常压室温等离子(ARTP)诱变对出发菌株进行诱变,结合三丁酸甘油酯平板透明圈法初筛,液态产酯化酶的二级快速筛选,结合固态培养产酶的三级筛选,获得一株乳酸乙酯酯化酶高产突变株黑曲霉(Aspergillus niger)T206。在液态产酶最佳条件下其乳酸乙酯合成量由出发黑曲霉T103的430.15 mg/L提高到530.18 mg/L,提高了23.56%,固态产酶最佳条件下由出发菌的727.88 mg/L提高到了892.15 mg/L,提高了22.71%。经5代传代培养,产酶性能稳定。  相似文献   

3.
低温常压等离子体处理羊毛改性技术研究   总被引:18,自引:1,他引:18  
卢可盛 《上海纺织科技》2004,32(2):31-33,59
在介绍等离子体处理羊毛纤维一般机理的基础上,着重研究低温常压等离子体连续处理羊毛的表面改性技术。对相关设备的设计和配置、技术路线和工艺参数的选择等,作了详细的论述。文章认为低温常压等离子体处理羊毛改性技术有工业推广和市场应用的较广阔前景。  相似文献   

4.
为提高核酸酶P1的发酵酶活,以桔青霉菌株CK-3为出发菌株,利用常压室温等离子体(ARTP)诱变方法,获得了3株(CK-3-1,CK-3-7,CK-3-9)高产核酸酶P1菌株,其中CK-3-9突变株酶活较高,其核酸酶Pl发酵酶活达到1232 U/m L,比出发菌株CK-3(酶活866 U/m L)提高到了42.2%,遗传实验表明稳定性好,有望用于工业化生产。   相似文献   

5.
In order to develop a catalyst with high activity for catalytic wet oxidation (CWO) processing at lower temperatures (35 degrees C) and atmospheric pressure, a new CuO-MoO3-P2O5 catalystwas synthesized by a solid-state reaction method and was characterized by X-ray diffraction (XRD), Fourier transformation infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), selected area electronic diffraction (SAED), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS) for elemental mapping. Methylene blue (MB) was adopted to investigate the catalytic activity of CuO-MoO3-P2O5 in CWO processing. The results show that this new catalyst has a high catalytic activity to decolorize MB under mild condition. The color removal of MB (the initial concentration was 0.3 g L(-1) and initial pH was 5) can reach to 99.26% within 10 min at 35 degrees C and atmospheric pressure. Catalyst lifespan and selectivity were also tested, and the results show that after the catalyst was used three times, catalyst activity still remains. Selectivity testing shows that CuO-MoO3-P2O5 has high catalytic activity on degradation of MB, whereas this catalyst has less impact on methyl orange (the color removal was 99.65% for MB and 55% for methyl orange under the same conditions). According to the experimental results, a possible mechanism of catalytic degradation of MB was proposed.  相似文献   

6.
常压室温等离子体诱变选育高产酸植物乳杆菌   总被引:2,自引:0,他引:2  
采用常压室温等离子体(ARTP)对从酸马奶中筛选的植物乳杆菌(Lactobacillus plantarum)YL15进行诱变,选育出产酸能力高并且发酵性能稳定的乳酸菌菌株,并对其遗传稳定性及最适生长温度和最适pH进行研究。结果表明,通过单因素试验确定最佳诱变条件为在120 W照射100 s,致死率为91.09%。通过溶钙圈法和酸度测定筛选出目标菌株YL15-4。初始菌株YL15产酸量为10×10-3 mol/L,诱变菌株YL15-4与初始菌株YL15相比较,其产酸能力提高了50%,产酸量达到15×10-3 mol/L,其最适生长温度和最适生长pH值分别37 ℃、5.0,并且遗传稳定性良好。  相似文献   

7.
该研究以BS120作为出发菌株,通过常压室温等离子体诱变(atmospheric and room temperature plasma,ARTP)技术进行诱变处理,第一轮以40 mg/L 8-氮鸟嘌呤为筛选拮抗物进行筛选,得到核黄素产量和得率分别提升61. 60%和58. 12%的菌株BSG1。第二轮诱变以300 mg/L寡霉素为筛选拮抗物进行筛选,筛选获得菌株BSG3,核黄素产量和得率较BS120分别提升83. 59%和78. 76%。将核黄素操纵子表达质粒pMX45转入BSG3中,得到菌株BSG5,核黄素产量达到(4 467. 08±99. 47) mg/L,得率为(42. 56±1. 25) mg/g葡萄糖,较BS120分别提高140. 94%和120. 52%,展现了良好的核黄素发酵性能和遗传稳定性。  相似文献   

8.
对从葡萄表面筛选的Y_6菌株进行常压室温等离子体(ARTP)诱变,通过单因素试验确定,处理时间100s,致死率98.70%为最佳诱变条件。采用三苯基氯化四氮唑(TTC)法、溴甲酚绿法以及杜氏小管等筛选出产酒精和产酸强的目标菌株Y_6-8,同时对其遗传稳定性进行研究。结果表明,将诱变菌株Y_6-8与出发菌株接进糖度相同的葡萄汁中,诱变菌株的产酒精、产酸能力分别提高了28.13%和214.93%,并且遗传性能稳定。  相似文献   

9.
以谷氨酸棒杆菌(Corynebacterium glutamicum)23798为原始菌株,对其进行常温常压等离子体(ARTP)诱变,以磺胺胍抗性和氨基酸与茚三酮特异显色为筛选标记,以期得到高产L-异亮氨酸的诱变谷氨酸棒杆菌,并对其遗传稳定性进行研究。结果表明,原始菌株23798经过ARTP诱变处理180 s后,经0.4 mg/mL磺胺胍抗性筛选、多孔板高通量筛选、发酵培养复筛,选育出一株高产L-异亮氨酸诱变谷氨酸棒杆菌(Corynebacterium glutamicum)B1。该菌株在摇瓶中发酵培养48 h,L-异亮氨酸产量达18.5 g/L,比原始菌株提高62.03%,且遗传性状稳定。  相似文献   

10.
利用常压室温等离子体(ARTP)诱变技术对酿酒酵母(Saccharomyces cerevisiae)NX4进行诱变,采用平板初筛、冰酒模拟汁发酵复筛低产挥发酸的突变菌株,并对其遗传稳定性及耐受性进行分析。同时利用该菌株酿造冰葡萄酒,对其理化指标、感官品质及挥发性风味物质进行分析。结果表明,获得一株低产挥发酸的突变体菌株T2-5,其具有良好的遗传稳定性。与原始菌株NX4相比,具有更高的糖耐受性和更低的酒精耐受性,利于在冰酒中应用。利用该菌株酿造的冰酒挥发酸产量降低26.4%,感官评分较高(77.14分),香气浓郁度有所降低,但持久性增强,具有典型的花香、蜂蜜、蜜桃、柠檬、甜瓜等热带水果香气。  相似文献   

11.
Detoxification of highly toxic polychlorinated aromatic compounds such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like compounds such as coplanar polychlorinated biphenyls (co-PCBs) under mild conditions (atmospheric pressure and room temperature) was achieved by a simple stirring operation for 24 h using metallic calcium in ethanol, without any tedious decomposition procedures and harsh conditions such as high temperature and/or high pressure. Metallic calcium can be kept stable under atmospheric conditions for a long period as compared to metallic sodium since the surface is coated with CaCO3, which is formed in the contact with air. Moreover, ethanol, which is one of the safest solvents for humans, acts not only as a solvent but also as an accelerator due to its ablility to remove the carbonated coating. This decomposition method for PCDDs, PCDFs, and co-PCBs therefore is one of the most economical and environmentally friendly detoxification methods with respect to the input energy and safety of reagents used. Concentration for each isomer of PCDDs, PCDFs, and co-PCBs was reduced in 98.32-100% conversions by treatment in ethanol at room temperature. The toxicity equivalency quantity (TEQ), which was measured by the HRGC-HRMS analysis, for the total residues of isomers was reduced from 22,000 to 210 pg TEQ/mL of hexane (conversion: 99.05%) at room temperature. By refluxing over 24 h, the conversion increased up to 99.45%.  相似文献   

12.
地衣芽孢杆菌(Bacillus lincheniformis)可以利用葡萄发酵产生四甲基吡嗪,四甲基吡嗪广泛应用于食品、临床和其他领域。该文以地衣芽孢杆菌BL1为出发菌株,采用常压室温等离子体诱变系统进行诱变,根据脱脂奶粉平板初筛、摇瓶发酵复筛,连续传代培养后得到遗传稳定的四甲基吡嗪产量较高的突变株BT12,该菌株摇瓶发酵生产四甲基吡嗪的最大产量为43.16 g/L,相比出发菌株的37.89 g/L的提高了13.91%。  相似文献   

13.
采用常压室温等离子体诱变技术处理黑曲霉B0201,选育高产单宁酶突变株,为单宁酶的发酵生产提供优良菌株。确定等离子体处理条件,采用稀释平板培养法挑选突变株,利用变色圈法和分光光度法测定产酶量,获得最佳诱变时间为180 s,正突变率高达19%。通过2%的高浓度单宁酸显色平板初筛850株菌,液态摇瓶发酵复筛90株菌,得到高产单宁酶的菌株B1401。诱变后单宁酶酶活为17.61 U/g,是原始菌株酶活8.94 U/g的2倍左右,且传代菌种产单宁酶稳定性良好。   相似文献   

14.
采用新型常压室温等离子体射流诱变拟无枝酸菌CCTCC M2011265(Amycolatopsis sp.),在等离子体对菌株致死率为61.71%的条件下,以香兰素产量为指标的正突变率达到17.6%,其中复筛得到遗传稳定性的高产突变株LQ-6,香兰素产量达到6.78 g/L,对前体阿魏酸的摩尔产率为72.14%,比出发菌株提高了21.29%,同时其香兰素合成代谢途径中的关键酶脱乙酰酶活性提高了43.2%,香兰素氧化酶活性降低了38.7%。  相似文献   

15.
该研究采用常压室温等离子体(ARTP)诱变技术对黑曲霉(Aspergillus niger)xj进行诱变,通过考察致死率与正突变率确定最佳诱变时间,通过发酵培养选育高产微生物絮凝剂菌株。结果表明,黑曲霉xj的最佳诱变照射时间为90 s;经初筛共得到416株诱变菌株;经复筛得到10株絮凝活性较高的诱变菌;再经同步发酵培养,比较突变菌的生长状态、絮凝活性及遗传稳定性,获得2株絮凝活性较高、稳定遗传的突变菌株A90-34与A90-37,其对高岭土悬液的絮凝率分别为94.12%和94.96%,与原始菌株相比,分别提高26.19%、27.03%,连续传代7次仍具有良好的遗传稳定性,絮凝率维持在92%~95%。  相似文献   

16.
常压室温等离子体快速诱变筛选高脯氨酸产率突变株   总被引:5,自引:2,他引:5  
为提高脯氨酸得率,采用新型常压室温等离子体(ARTP)诱变L-脯氨酸生产菌株———嗜醋酸棒杆菌(出发菌株为谷氨酸生产菌,菌拉丁名ATCC-13870),结合48孔板的高通量筛选手段,在致死率为99%的条件下,获得了16株生长速率和脯氨酸产率变化的菌株。发酵实验结果表明,筛选得到的高产脯氨酸突变体D3在发酵48 h,其脯氨酸浓度从原始菌对照组的54.7 g/L提高到65.8 g/L。  相似文献   

17.
目的通过等离子体诱变筛选获得高产虾青素的雨生红球藻突变株。方法将常压室温等离子体应(atmospheric and room temperature plasma,ARTP)用于雨生红球藻的诱变育种处理。ARTP在常温下以输入功率100 W、处理距离2mm、气体流速10 L/min处理雨生红球藻40s,雨生红球藻的致死率达90%以上。在此条件下获得诱变株后,以虾青素合成抑制剂作为筛选剂,成功筛选获得一株虾青素高产藻株M45。结果该突变株的生物量和生长速率分别较出发株提高了6.45%和8.57%。突变株M45的虾青素含量达3.1%,较出发株提高了51.96%;虾青素产量为71.92 mg/L,相比于出发株提高了61.73%,且遗传稳定性实验表明,M45生产性能稳定。结论经等离子体诱变获得的突变株M45虾青素含量高,生产性能稳定,具有一定的工业应用前景,等离子体诱变方法适用于雨生红球藻的育种。  相似文献   

18.
利用常压室温等离子体(ARTP)技术对黑曲霉(Aspergillus niger)FXY进行诱变处理,并对菌株的遗传稳定性及所产木聚糖酶的酶学性质进行了研究。结果表明,筛得一株高产木聚糖酶且能稳定遗传的菌株ARTP-82,其所产木聚糖酶酶活为175.33 U/mL,较出发菌株提高了120.8%。酶活的提高与酶比活力增加有关、与菌株生物量增加无关;该木聚糖酶的最适温度为45.0 ℃、最适pH值为7.0,在该温度和pH值条件下酶的稳定性良好。  相似文献   

19.
建立了各卷烟纸在不同地点(不同大气压)透气度线性换算修正方程,经过验证40~70CU卷烟纸在不同地点(不同大气压)透气度修正后的准确性大于98.2%。因此,该方法可以指导不同地点卷烟纸透气度的测定、换算和比较。  相似文献   

20.
研究了高压处理中压力和温度对华根霉脂肪酶的活力和稳定性的影响,并利用活性酶变性酶的双态模型考察了酶的热变性,并构建压力—温度二元相图。研究结果表明:在0.1~200.0 MPa时,华根霉脂肪酶活力随压力提升而增加,其中在压力200 MPa时酶活达到最高值,是常压下初始酶活的116%;当压力超过200 MPa时,酶活开始降低,尤其在400~600MPa范围内迅速降低。压力—温度协同作用下华根霉脂肪酶的加工稳定性数据显示,在200 MPa、40℃下酶热稳定性最佳,压力超350 MPa时酶热稳定性显著降低。  相似文献   

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