硫酸盐还原菌对喷气燃料腐蚀性质的影响

选取脱硫弧菌属及脱硫肠状菌属两种硫酸盐还原菌作为试验对象分别进行培养观察,通过试验模拟储存喷气燃料底层水发生硫酸盐还原菌污染,并根据银片腐蚀试验及MPN计数法考察硫酸盐还原菌能否利用喷气燃料中的含硫化合物进行生长代谢及硫酸盐还原菌对喷气燃料腐蚀性质的影响。结果表明:硫酸盐还原菌自身不能直接利用喷气燃料中的含硫化合物进行正常的生长代谢;硫酸盐还原菌可以造成喷气燃料银片腐蚀不合格且银片在油相中的腐蚀级别高于水相;底层水中的硫酸盐还原菌浓度越高,其腐蚀银片的速度就越快;在当前试验体系下,当底层水中硫酸盐还原菌的浓度超过9.5个/mL时即可造成喷气燃料银片腐蚀不合格。     

喷气燃料银片腐蚀机理及解决方法

综述了喷气燃料银片腐蚀机理及解决方法。结果发现,引起银片腐蚀试验不合格的原因是活性硫化物,主要是单质硫。采用补充精制工艺,可以解决喷气燃料的银片腐蚀问题,对产品的相关性能没有影响。     

十二烷烃降解菌的筛选,鉴定及降解条件的优化

在以十二烷为唯一碳源的筛选培养基中,从辽河油田采油井附近长期被石油污染的土壤中,分离、筛选出一株可以以十二烷烃作为唯一碳源的高效的微生物降解菌种。通过一系列的形态特征及生理生化特征的实验结果,可以鉴定为假单胞菌属。通过改变菌种培养过程的不同条件,可以得到其对菌株生长及十二烷降解的影响,实验结果表明:该菌株降解十二烷的最适温度为37℃,最适接种量为10%,最适降解的正十二烷浓度为500 mg/L,最适pH值为8.0,在最佳条件下,十二烷72 h内降解率达到65.2%。     

微波场下喷气燃料银片腐蚀图像颜色识别

为研究微波场下喷气燃料银片腐蚀图像颜色识别,本文对比了多个颜色空间模型,经过分析验证:HSV和LAB颜色模型用于喷气燃料银片腐蚀图像颜色识别,其识别度较高,可广泛应用于微波场下腐蚀图像的颜色识别。HSV颜色空间可用于检测所测油样的具体腐蚀级别上,LAB颜色空间用于检测待测油样是否腐蚀上,研究结果为喷气燃料银片腐蚀图像颜色等级自动识别提供了理论研究基础。     

微生物在变压器油中的生长研究

取土壤样通过富集、分离、纯化等方法,得到能以变压器油为唯一碳源的好氧细菌和厌氧细菌,说明自然环境中的确存在能利用变压器油为碳源生长繁殖的细菌.在不同条件下,以变压器油为唯一碳源进行好氧和厌氧培养,当体系在无游离水条件下、温度≥50℃或pH值≤5.0时,微生物均不能生长繁殖,说明在变压器油工作状态下,微生物不能在其中生长繁殖.从运行中的介损值偏高的变压器中取油样,未检测出微生物.     

绿色木霉菌对喷气燃料理化性质影响的研究

对绿色木霉菌(Trichoderma viride)油水体系进行培养,并对喷气燃料理化性质进行分析。试验结果表明,随着培养时间的延长,喷气燃料中颗粒数明显增加,而诱导时间以及表面张力减小。另外,喷气燃料中绿色木霉菌的存在加速了铜片腐蚀,这对储存油罐以及输油管道构成巨大威胁。说明木霉菌作为一个主导污染真菌对喷气燃料的理化性质有重要影响。     

黄孢原毛平革菌降解光氧化褐煤的过程特性

研究了黄孢原毛平革菌降解光氧化内蒙胜利褐煤的过程特性,分析了降解过程的微量热曲线,并比较了降解液、纯培养液及培养基溶煤液的pH值、表面张力及450 nm处吸光度A_(450)值随培养时间的变化情况。结果表明,黄孢原毛平革菌降解光氧化内蒙胜利褐煤的微量热曲线可分为迟缓期、指数生长期、稳定期和衰亡期,与菌株的生长曲线相吻合,降解过程释放的总热量为186.73 kJ·g~(-1),降解时间为15.1 d,指数生长期生长速率常数k为4.040 8×10~(-4) min~(-1);黄孢原毛平革菌在生长代谢过程中产生了碱性物质和表面活性剂,与纯培养液相比,降解液的pH值降低、表面张力增强;黄孢原毛平革菌纯培养液和培养基溶煤液的A_(450)值均很小,充分证实黄孢原毛平革菌的作用使得光氧化内蒙胜利褐煤发生了降解。     

正十六烷降解菌的分离、鉴定及降解特性

以正十六烷为唯一碳源进行选择性富集培养,从石油污染土壤中筛选出1株正十六烷降解菌;根据形态观察和自动化鉴定分析,初步确定其为铜绿假单胞菌(Pseudomonas aeruginosa);采用气相色谱法测定了其对正十六烷的降解作用。结果表明,该菌株降解正十六烷的作用明显,在pH值为7.0时降解效果最好。     

航空燃料系统微生物危害及防护

航空燃油能够为微生物提供合适的生长环境,如水分及微生物生长所需的碳源、氮源和微量元素等。微生物在航空燃油中生长繁殖会对航空燃料系统造成腐蚀。这种微生物腐蚀会严重影响航空器和燃料系统的安全。本文对航空燃料系统微生物腐蚀的原因、危害及普遍采用的防护方法方法进行综述并对航空燃料系统的微生物腐蚀防护研究进行展望。     

产表面活性物质的低温菌去除冬季海水中石油污染物研究

冬季发生的溢油对海洋环境危害巨大。利用低温微生物进行石油污染物修复是一种有效方法。本研究从石油污染的表层海水中筛选出一株能以石油烃为唯一碳源并且在接近海水冰点的低温下依然能保持活性的低温菌,该菌株能产生表面活性物质促进石油烃降解。实验结果表明,在低温下该菌株能利用多种碳源产生表面活性剂,其中以正十六烷和柴油为唯一碳源时发酵液的表面张力可分别降低到28和35 mN/m。在接近海水冰点的条件下,经过90 d的培养,该菌株可将海水中的柴油降解33%,添加生物表面活性剂后可将降解率提高到39%。     

月桂酰胺丙基氧化胺的吸附性能研究

合成了月桂酰胺丙基氧化胺(LAO),利用p H计测定了其等电点,利用高效液相色谱仪、表面张力仪分别研究了p H和温度等因素对其在石英砂表面吸附性能的影响以及其对十二烷-水-玻璃三相接触角的影响。结果表明:LAO的等电点在p H=9左右;随着p H升高,LAO水溶液的临界胶束浓度降低;随着温度和p H的升高,LAO在石英砂表面的吸附量下降;随着LAO质量浓度的增加,十二烷-水-玻璃三相接触角先增加后减小至平衡;LAO在石英砂表面的吸附为双层吸附。     

Chemical characterization and physicochemical behavior of biosurfactants

Microbes have been isolated from soil and water samples after an enrichment culture process with kerosene and tested for biosurfactant production by measuring the surface and interfacial tensions and emulsification power of culture broths. The isolation and characterization of extracellular surface-active agents from the culture broth of Pseudomonas aeruginosa 44T1 strain have been made. Preliminary structure identification with specific TLC reagents of the CHCl₃MeOH (2:1) extracts showed two spots with a glycolipidic structure and Rf values of 0.70 and 0.45, respectively, using the solvent system CHCl₃:MeOH:H₂O (65:25:4). Separation of surface active agents by Chromatographic absorption column in Florisil or silica gel and further spectroscopic study (IR, 1H-NMR, 13C-NMR) and chemical degradation techniques (acid and alkaline hydrolysis) gave a structure of β[β(2-0-α-L-rhamnopyranosyloxy)decanoyl] decanoic acid and β[β (2-0-α-L-rhamnopyranosyl-α-L-rhamnopyranosyloxy) decanoyloxy] decanoic acid (glycolipid A and glycolipid B, respectively) for the two glycolipids detected. A new method of mass spectrometry, fast atom bombardment mass spectrometry (FABMS), was used to probe molecular structure. The mass spectra obtained contain molecular weight recognition and sequence information signals, and they are in agreement with the proposed structures. Physicochemical evaluations of the two isolated glycolipids were made. The minimum surface tension obtained was 25 mN/m in water solutions. At pH 7 the CMC value was 11 ppm. In both cases, at pH 3 the CMC was displaced to lower and at pH 9 it was displaced to higher concentration values. Glycolipid B showed a lower value of interfacial tension (0.2 mN/m) than glycolipid A (1.0 mN/m). Glycolipid A showed a lower CMC value at alkaline pH, whereas glycolipid B had a lower CMC at acidic pH than at alkaline pH.     

Biosurfactant production by <Emphasis Type="Italic">Bacillus coagulans</Emphasis>

A new biosurfactant producer, Bacillus coagulans, was isolated from soil. Its 24-h-old culture broth had a low surface tension (27–29 mN/m). Optimization of cell growth of this bacterium led to maximal biosurfactant production with glucose or starch as the organic carbon source, a pH in the range 4.0–7.5, and incubation temperatures from 20 to 45°C. The crude biosurfactants obtained after neutralization and lyophilization of the acid precipitate yielded a minimal aqueous solution surface tension value of 29 mN/m and an interfacial tension value of 4.5 mN/m against hexadecane. The critical micelle concentration of the crude biosurfactants was 17 mg/L. Addition of NaCl to the aqueous solution of the crude product caused lowering of surface tension at both the aqueous solution-air and aqueous solution-n-hexadecane interfaces. These results indicate that the biosurfactants obtained have potential environmental and industrial applications and may have uses in microbially enhanced oil recovery.     

十一烯酸基乳化剂制备及应用研究

利用十二醇(DA)与十一烯酸(UA)/马来酸酐(MAH)共聚物通过酯化反应制备了UMA-DA聚合物，并将聚合物作为乳化剂用于UA与甲基丙烯酸甲酯(MMA)的乳液聚合中。FT-IR分析表明：DA中的羟基与UMA共聚物中的酸酐发生了反应。¹H NMR结果表明：在δ 3.2~3.4处有明显的—O—CH₂—质子信号，表明成功制备了UMA-DA共聚物。通过表面张力法对UMA皂化物的临界胶束浓度(CMC)值进行了测定，UMA-DA的CMC值为9.6 g/L，此时表面张力γ_CMC为23.04 mN/m, UMA-DA的γ_CMC值要远低于纯水(71.97 mN/m)。在乳液聚合时，随UMA-DA用量的不断增加，乳液粒径和粒径分散系数(PDI)增大，凝胶率逐渐减小。当自制乳化剂UMA-DA用量为总单体的10%且UA与MMA质量比10 : 90时乳液较为稳定，总单体转化率为98.1%。     

航煤液相加氢产品腐蚀性因素分析及对策

航煤产品铜片腐蚀主要与某些活性硫化物和有机酸相关,这些活性硫化物主要包括元素硫、硫化氢、硫氢化铵、硫醇、硫的氧化物、磺酸和酸性磺酸酯等.另外,航煤产品中存在其他杂质,如碱性物质、氯化物等也能对铜片产生腐蚀.加氢精制后航煤原料中有机酸、硫醇和碱性物等基本脱除,但由于航煤原料中含有微量氮,加氢后能与硫、氯生成硫氢化铵和氯化...     

酵母菌的磁性载体固定化及处理精炼大豆油废水

采用发酵性丝孢酵母菌处理精炼大豆油废水,首先利用海藻酸钠和所制备的Fe₃O₄磁性载体分别对酵母菌进行固定化,然后分别用酵母菌、磁性载体、海藻酸钠固定化酵母菌和磁性载体固定化酵母菌来处理精炼大豆油废水。对处理结果进行对比分析,结果显示：4种物质中,磁性载体固定化酵母菌对精炼大豆油废水处理36 h时效果最佳。pH值6.0比较适合磁性载体固定化酵母菌的生长,处理36 h的废水中的酵母菌的OD₆₀₀值为19.78。通过研究不同pH值和不同接种量条件对磁性载体固定化酵母菌处理精炼大豆油废水的情况,得到处理废水的较优条件：废水pH值6.0,酵母菌接种量10%,处理时间36 h,此条件下废水的化学需氧量(COD)值为2 430 mg/L。     

DYNAMIC SURFACE EFFECT ON THE BOILING OF MIXTURES

It is possible that the critical boiling heat flux of mixtures exceeds that of the components considerably. This effect has been attributed to the slowing down in bubble growth rate caused by the exhaustion of the volatile component near the vapor-liquid interface (the F effect) and the retardation of bubble coalescence due to surface tension gradient caused by the evaporation of component of lower surface tension (the M effect). The growth and coalescence of vapor bubbles are dynamic processes. The surface tension of a fast stretching surface of a binary mixture is higher than the static value because the component of lower surface tension cannot diffuse to the adsorbed layer promptly. This dynamic effect is represented quantitatively by a Y function.

The Y values for various binary systems are plotted versus concentration along with the F and M values in comparison with the critical heat flux values. The resemblance between these curves shows that F, M and Y effects are all partial reasons for the increasing of the critical heat flux. They are interrelated and further studies are desirable. The agreement between variation of the tray efficiencies of a fractionation distillation column and that of the Y values shows another example of that the dynamic surface effect is an important factor in many heat and mass transfer operations     

DYSB两性双子表面活性剂的合成与性能测定

以无水对氨基苯磺酸、1,4-二溴正丁烷、溴代十二烷、溴乙烷为主要原料,由氨的烷基化和季铵化反应合成了丁撑-双(乙基十二烷基对磺酸苯基)溴化铵(DYSB),属于磺基甜菜碱两性双子表面活性剂,其水溶液在25℃时的表面活性数据为:cmc=5.0×10-4mol/L,γcmc=25.8 mN/m。研究了无机阳离子和无机阴离子作为反离子对目标产物水溶液表面活性的影响,随着无机盐(NaCl、MgCl2、Na2SO4)浓度的增大,DYSB水溶液表面张力逐渐减小,最终趋于一定值,并且阴离子型反离子对目标产物表面活性的影响比阳离子型反离子的大。     

Biodesulfurization of dibenzothiophene sulfone by Arthrobacter sp. and studies with oxidized Illinois No. 6 coal

A bacterium identified as Arthrobacter sp. was grown on dibenzothiophene (DBT) sulfone as a sole source of sulfur, producing sulfite and sulfate. Sulfur in DBT sulfone (1.0 mM) was nearly quantitatively converted to sulfate by the organism. The organism could also use DBT sulfone as a sole source of carbon and energy. There was evidence for transient accumulation of benzoic acid in the culture medium after growth of the cells slowed. The DBT sulfoxide analogue 9-fluorenone was converted by resting cells to a product identified as 1,10-dihydroxy-1,10-dihydrofluoren-9-one, suggesting that DBT sulfone may be metabolized via an angular hydroxylation resulting in carbon- sulfur bond cleavage. This strain of Arthrobacter showed no ability to desulfurize oxidized Illinois No. 6 coal.     

无患子皂素的表面活性及复配增效性能

无患子皂素是一种天然非离子型表面活性剂,30℃时其临界胶束浓度(cmc)值为0.1g/L,最低表面张力(g_cmc)为48.48mN/m,具有较好的表面活性。30～60℃之间,无患子皂素的g_cmc与cmc值基本保持不变;溶液偏酸性时,无患子皂素的最低表面张力下降幅度较大,cmc值不变;盐度对无患子皂素表面性能有一定的影响。此外,无患子皂素具有较好的抗硬水能力,且与其他合成表面活性剂复配有一定的增效作用,尤其是与十六烷基三甲基溴化铵形成的复配体系,其临界胶束浓度增效50.0%,并且降低表面张力的能力增效4.08%。无患子皂素起泡性强,泡沫稳定,国标GB/T 7162—1994条件下(溶液浓度C=2.5g/L)泡沫高度H₀为135.6mm,且复配体系的初始泡沫高度均有一定的增加。