利用两种微生物的协同作用进行柴油的深度脱硫

红串红球菌通过4S途径降解二苯并噻吩(DBT)产生 和2-羟基联苯(2-HBP). 和2-HBP的存在对红串红球菌的进一步脱硫有抑制作用, 加入脱 和2-HBP 的菌株可以解除 和2-HBP对红串红球菌脱硫反应的抑制, 使该反应继续向生成产物的方向移动, 从而提高其脱硫率. 在脱硫菌和专一性降解 的水解好氧菌(代号: PYS)的协同作用下可以使高浓度的DBT从1.142 mmol/L降到0.0468 mmol/L, 降解率达到95.9%, 比没有加PYS时提高32%的脱除率. 在油水比为1∶9的条件下, 可以将柴油中的硫从554 mg/mL降到306 mg/mL, 降解率达到44.8%.     

传质助剂对柴油生物脱硫过程的影响

以从胜利油田被高含硫原油污染的土壤中筛选到的根癌土壤杆菌UP-3为研究对象,考察了模拟油体系中传质助剂对该菌株生物脱硫效果的影响,同时研究了在传质助剂存在条件下油水比、反应时间和硫含量对UP-3生物脱硫性能的影响。结果表明,该生物脱硫菌在脱除含硫化合物的同时不消耗其它烃类物质;传质助剂吐温80能够提高UP-3对模拟油中的脱硫率;吐温80存在时,UP-3在3d内可将模拟油（含硫量200mg／L）中98．01％的硫脱除;UP-3对柴油最高的脱硫率仅达到31．81％,需要进一步提高其对有机硫化物的脱硫活性。     

复杂精油--丁香油的挥发性成分分析

利用GC-MS联用技术和双柱定性法对烟用精油——丁香油的挥发性成分进行分析,共鉴定出28种化学成分,主要成分为丁香酚、石竹烯、环氧石竹烯等。本文着重讨论了GC-MS联用技术分析复杂精油时的定性定量问题。分析结果为香精香料的质量控制、产品开发和调香等提供指导作用。     

Ortho-Hydroxylation of Phenol by Tyrosinase Model Compounds

A series of tyrosinase model ligands and complexes containing polyimidazoles were prepared. 2, 4-Di-tert-butyl-phenol was ortho-hydroxylated by the binuclear copper (I) complex [Cu2(6a)(CH3CN)2](ClO4)2 8a and molecular dioxygen under mild conditions with up to 80.4% yield, 91.4% selectivity and 92.0% conversion.     

复合菌体及单一菌体催化的微生物燃料电池产电机理初步研究

利用淡水沉积物作为接种源构建了微生物燃料电池,考察苯酚对该微生物燃料电池性能的影响.结果表明,在淡水沉积物接种的微生物燃料电池中,电流的产生是由富集在电极表面的细菌引起的.苯酚降低了细菌消耗葡萄糖的速率,并在加入相同量葡萄糖的情况下,延长了产电时间.另一方面,实验还研究了一株从沉积物微生物燃料电池中分离出的单菌株的产电情况.该菌株在微生物燃料电池中需要借助自身代谢产生有电极反应活性的中间产物才能产电.GC-MS分析表明,中间产物中有吩嗪类物质,该类物质可在该细菌细胞与石墨电极之间充当电子传递介体,实现电子从细胞向电极的传递.     

原油中含氧化合物的质谱分析

本文介绍自原油分离含氧化合物,酯化混合酸和用毛细管气相色谱-质谱(GC-MS)鉴定其组分的方法。色谱-质谱分离并鉴定出C_8—C_(30)的脂肪酸、分子量为484和498的二对藿烷酸的立体异构体,烷基酚,邻苯二甲酸酯等,并首次发现石油中含有癸二酸二异辛酯类组分。     

Separation of Biphenyl Nitrile Compounds by Microemulsion Electrokinetic Chromatography with Mixed Surfactants

A mixture of nine biphenyl nitrile compounds with high hydrophobicity and similar structures was successfully separated by microemulsion electrokinetic chromatography (MEEKC) within 30 rain. The buffer system contained 100 mmol/L sodium dodecyl sulfate (SDS), 80 mlnol/L sodium cholate (SC), 0.81% heptane, 7.5% n-butanol, 10% acetonitrile and 10 mmol/L borate. The addition of SC, organic modifiers, sample preparation and temperature all showedremarkable effect on the separation. Meanwhile, the MEEKC method was briefly compared with micellar electrokinetic chromatography (MEKC) method.     

中心切割GC-MS法分析煤液化油中的酚类化合物

使用碱洗提酚法提取煤液化油中的酚类化合物,然后结合Deans Switch装置和LTM色谱柱模块,采用中心切割气相色谱(GC)-质谱(MS)法对提取的酚类化合物进行定性。采用GC建立标准曲线,对煤液化油中主要酚类化合物的质量分数进行测定,并测定了煤液化油中邻甲基苯酚、2-乙基苯酚、4-丙基苯酚和5-茚酚4种酚类化合物的加标回收率。结果表明,在煤液化油中共定性出51种酚类化合物,测定了其中的35种酚类化合物的质量分数,其量占煤液化油总量的2.54(wt)%,苯酚和烷基苯酚占35种酚类化合物的88.2(wt)%。煤液化油中4种酚类化合物的加标回收率高,重复性好。     

Mechanism of Chlorination by Means of Deuterated Model Compounds

β,β-Dideuterated poly(viny1 chloride) (β,β -d2-PVC) was chlorinated under conditions of photochemical suspension chlorination in concentrated hydrochloric acid with addition of chloroform as a swelling agent, and also under conditions of thermal solution chlorination in tetrachloroethane. The ¹H-NMR spectra of chlorinated β,β -d₂PVC (β,β -d₂CPVC) were measured. The deuterium concentration was determined in combustion products of β,β -d₂CPVC as the D₂O:H₂ O ratio by means of mass spectroscopy. It was found that the concentration of CHC1- groups decreases in both the photochemical suspension chlorination and in the thermal solution chlorination. The structural nonidentity of β,β -d₂PVC chlorinated in suspension and in solution was confirmed.     

Biodiesel Production by Single and Mixed Immobilized Lipases Using Waste Cooking Oil

Biodiesel is one of the important biofuels as an alternative to petroleum-based diesel fuels. In the current study, enzymatic transesterification reaction was carried out for the production of biodiesel from waste cooking oil (WCO) and experimental conditions were optimized, in order to reach maximum biodiesel yield. Bacillus stearothermophilus and Staphylococcus aureus lipase enzymes were individually immobilized on CaCO₃ to be used as environmentally friendly catalysts for biodiesel production. The immobilized lipases exhibited better stability than free ones and were almost fully active after 60 days of storage at 4 °C. A significant biodiesel yield of 97.66 ± 0.57% was achieved without any pre-treatment and at 1:6 oil/methanol molar ratio, 1% of the enzyme mixture (a 1:1 ratio mixture of both lipase), 1% water content, after 24 h at 55 °C reaction temperature. The biocatalysts retained 93% of their initial activities after six cycles. The fuel and chemical properties such as the cloud point, viscosity at 40 °C and density at 15 °C of the produced biodiesel complied with international specifications (EN 14214) and, therefore, were comparable to those of other diesels/biodiesels. Interestingly, the resulting biodiesel revealed a linolenic methyl ester content of 0.55 ± 0.02% and an ester content of 97.7 ± 0.21% which is in good agreement with EN14214 requirements. Overall, using mixed CaCO₃-immobilized lipases to obtain an environmentally friendly biodiesel from WCO is a promising and effective alternative for biodiesel production catalysis.     

Synthesis and Electrochemical Behavior of Mixed Organoboron/Organomercury Compounds

As part of our ongoing interest in the synthesis and reduction chemistry of organoboron species, we have investigated the synthesis of mixed organoboron/organomercury complexes by reaction of the Li(THF)₄ salt of dimesityl‐1, 8‐naphthalenediylborate with 1, 2‐(HgCl)₂C₆F₄ and 1, 3‐(HgCl)₂C₆F₄, respectively. The resulting tetranuclear B₂Hg₂ complexes ( 2 and 3 , respectively) were characterized by multinuclear NMR spectroscopy and single‐crystal X‐ray analysis. The cyclic voltammogram of complex 2 , which features a B–Hg–Hg‐B core connected by an ortho‐phenylene (Hg–Hg connection) and two peri‐naphthalenediyl linkers (B–Hg connection), shows significant coupling of the two electroactive boryl units, presumably via a direct σ interaction of the vacant p orbitals of the four neighboring Lewis acids. This conclusion is supported by DFT calculations, which show that the LUMO of 2 spans the four Lewis acids, with a major in phase contribution from the boron 2p orbitals and the mercury 6p orbitals.     

Separation and Chemical Characterization of Wetting Crude Oil Compounds

To improve the understanding of wettability, especially the influence of colloidal stability and composition of crude oil, wetting experiments on quartz sand were performed with an asphaltene-rich oil, a resin-rich oil, and with model oils containing different colloid compositions. A two-step procedure was developed to investigate the wetting behavior. In the first step those crude oil components were extracted, which preferentially wet solid surfaces. The extracted crude oil components were characterized in the second step. The amount of adsorbed oil components correlates with the stability of the crude oil colloids: low colloidal stability of crude oil leads to larger amounts of adsorbed components than does high colloidal stability. The addition of resins and/or low molecular weight asphaltenes to the crude oil stabilizes the crude oil colloids; i.e., a lower amount of wetting components are isolated by extraction in such systems. To find out, which fraction of the adsorbed oil components determines the wetting behavior of a crude oil, the wetting properties of the toluene solutions of these fractions were compared to those of the toluene solutions of the precipitated crude oil colloids. The fractions extracted with the solvent systems chloroform and methanol/chloroform showed nearly the same wetting behavior as the crude oil colloids. These fractions are characterized by the highest molecular weights, higher sulfur compositions, and the lowest H/C ratios. On the other hand, the nitrogen compounds predominate in the acetone fraction.     

俄罗斯直馏柴油中硫化物的分离富集与结构鉴定

采用选择性氧化剂和还原剂对俄罗斯直馏柴油中的硫醚类硫化物和噻吩类硫化物分别进行分离和富集,得到两者的浓缩液。运用质谱技术对分离出的硫化物结构进行鉴定。结果表明:氧化还原法是分离俄罗斯直馏柴油中硫化物的有效方法;硫醚类硫化物浓缩液中鉴定有烷基四氢噻吩和烷基四氢噻喃类化合物,四氢噻喃类硫化合物的烷基取代碳数在C4~C13范围;噻吩类硫化物浓缩液中有烷基侧链长度为C0~C9之间的苯并噻吩,烷基侧链长度为C0~C3之间的二苯并噻吩。     

Enhanced Biodegradation of Alkane Hydrocarbons and Crude Oil by Mixed Strains and Bacterial Community Analysis

In this study, two strains, Acinetobacter sp. XM-02 and Pseudomonas sp. XM-01, were isolated from soil samples polluted by crude oil at Bohai offshore. The former one could degrade alkane hydrocarbons (crude oil and diesel, 1:4 (v/v)) and crude oil efficiently; the latter one failed to grow on alkane hydrocarbons but could produce rhamnolipid (a biosurfactant) with glycerol as sole carbon source. Compared with pure culture, mixed culture of the two strains showed higher capability in degrading alkane hydrocarbons and crude oil of which degradation rate were increased from 89.35 and 74.32?±?4.09 to 97.41 and 87.29?±?2.41 %, respectively. In the mixed culture, Acinetobacter sp. XM-02 grew fast with sufficient carbon source and produced intermediates which were subsequently utilized for the growth of Pseudomonas sp. XM-01 and then, rhamnolipid was produced by Pseudomonas sp. XM-01. Till the end of the process, Acinetobacter sp. XM-02 was inhibited by the rapid growth of Pseudomonas sp. XM-01. In addition, alkane hydrocarbon degradation rate of the mixed culture increased by 8.06 to 97.41 % compared with 87.29 % of the pure culture. The surface tension of medium dropping from 73.2?×?10^?3 to 28.6?×?10^?3 N/m. Based on newly found cooperation between the degrader and the coworking strain, rational investigations and optimal strategies to alkane hydrocarbons biodegradation were utilized for enhancing crude oil biodegradation.     

Epigenetic Modifications Induced by Olive Oil and Its Phenolic Compounds: A Systematic Review

Many studies demonstrated that olive oil (especially extra virgin olive oil: EVOO) phenolic compounds are bioactive molecules with anti-cancer, anti-inflammatory, anti-aging and neuroprotective activities. These effects have been recently attributed to the ability of these compounds to induce epigenetics modifications such as miRNAs expression, DNA methylation and histone modifications. In this study, we systematically review and discuss, following the PRISMA statements, the epigenetic modifications induced by EVOO and its phenols in different experimental systems. At the end of literature search through “PubMed”, “Web of Science” and “Scopus”, 43 studies were selected.Among them, 22 studies reported data on miRNAs, 15 on DNA methylation and 13 on histone modification. Most of the “epigenomic” changes observed in response to olive oil phenols’ exposure were mechanistically associated with the cancer preventive and anti-inflammatory effects. In many cases, the epigenetics effects regarding the DNA methylation were demonstrated for olive oil but without any indication regarding the presence or not of phenols. Overall, the findings of the present systematic review may have important implications for understanding the epigenetic mechanisms behind the health effects of olive oil. However, generally no direct evidence was provided for the causal relationships between epigenetics modification and EVOO health related effects. Further studies are necessary to demonstrate the real physiological consequences of the epigenetics modification induced by EVOO and its phenolic compounds.     

顶空气相色谱法测定大蒜主要含硫化合物在烹饪后油脂中的含量

采用顶空毛细管气相色谱法/氢火焰离子化检测器,分析了大蒜中主要含硫化合物(如:二烯丙基硫醚、二烯丙基二硫醚、二烯丙基三硫醚)在烹饪后油脂中的含量变化。优化的色谱条件为以DM2WAX石英弹性毛细管色谱柱进行分离,平衡温度为403 K,搅拌速度为500 r/min,平衡时间为20 min。在所考察的浓度范围内,该方法呈现出良好的线性关系,相关系数大于0.999,检出限为0.001~0.025 mg/L,3种含硫化合物的平均回收率为97.1%~103.0%。     

混合价化合物概述及进展

混合价化合物在分子材料和生命科学的研究领域起着重要作用 ,本文就混合价化合物的定义、存在、历史及分类等作一简单介绍。