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旨在为米糠油适度加工提供数据支撑，对来自国内3个工厂的不同加工阶段米糠油的理化指标、组成、色泽和微量成分进行了测定。结果表明：A、B、C 3个工厂的米糠油在精炼后酸值（KOH）分别由24.22、18.95、17.21 mg/g降至0.15 mg/g以下，脂肪酸脱除率高达99%以上，过氧化值分别降至0.99、1.54、0.71 mmol/kg，精炼后米糠油酸值、过氧化值均达到GB/T 19112—2003中一级油标准；3个工厂的米糠油在加工过程中其游离脂肪酸含量变化趋势与酸值的变化趋势一致；精炼后米糠油甘一酯含量降低了58.9%~84.9%，主要在物理脱酸和脱臭时脱除，甘二酯含量变化不大，甘三酯含量增加了12.8%~23.9%；3个工厂米糠油脂肪酸组成在加工过程中没有明显变化；精炼后米糠油中叶绿素被有效脱除，色泽均达到国标一级油标准；米糠油的微量成分在加工过程中变化极大，其中谷维素出现明显的损失，损失率高达80.8%~94.1%，主要在化学脱酸时损失，甾醇损失率为21.2%~42.6%，主要在化学脱酸时损失，维生素E含量变化趋势存在差异，A工厂维生素E含量增加30.2%，B、C工厂维生素E损失率分别为31.7%、55.6%；角鲨烯损失率为659%~963%，主要发生在脱臭工序。综上，企业应根据自己的定位，合理调整精炼工序，优化精炼工艺参数，生产出符合企业追求的米糠油产品。Aiming to provide data support for the moderate processing of rice bran oil, the physicochemical indexes, composition, colour and trace components of rice bran oil at different processing stages from three different plants in China were determined. The results showed that the acid value of rice bran oil from three plants A, B and C after refining reduced from 24.22, 18.95 mgKOH/g and 17.21 mgKOH/g to less than 0.15 mgKOH/g respectively, and the fatty acid removal rate is more than 99%. The peroxide value was reduced to 0.99, 1.54 mmol/kg and 0.71 mmol/kg respectively. The acid value and the peroxide value of the refined rice bran oil reached the standard of first-grade oil in the GB/T 19112-2003. The change trend of free fatty acid content in rice bran oil in three plants was consistent with that of acid value. The monoglyceride content in rice bran oil decreased by 58.9%-84.9%, mainly removed in the physical deacidification and deodorization, the diglyceride content did not change much, and the triglyceride content increased by 128%-239%. The fatty acid composition of rice bran oil in the three plants did not change significantly during processing. After refining, chlorophyll in rice bran oil was effectively removed, and the colour reached the national standard of first-grade oil. The trace componens of rice bran oil changed greatly during processing, among which oryzanol appeared obvious loss, with the loss rate 80.8%-94.1%, mainly loss in chemical deacidification; sterol loss rate was 21.2%-42.6%, mainly loss in chemical deacidification; vitamin E changed differently, vitamin E content increased by 30.2% in plant A, but reduced by 31.7% and 55.6% in plant B and plant C respectivevly. The loss rate of squalene was 659%-96.3%, mainly occurred in the deodorization. To sum up, the enterprise should adjust the refining process reasonably according to its own position, optimize the refining parameters, and produce the rice bran oil products in line with the enterprise′s pursuit.

旨在实现大豆油的精准适度加工和开发零反式脂肪酸的双温脱臭工艺，分析了大豆油常规单温脱臭(脱臭温度240~260 ℃)精炼的原油、中和油、脱色油、脱臭油和降温脱臭(脱臭温度240~260 ℃降至220 ℃左右)精炼的脱臭油中生育酚、甾醇等有益微量成分和反式脂肪酸、3-氯丙醇酯等有害微量成分的含量变化。结果表明：大豆油常规单温脱臭精炼工艺下，生育酚和甾醇在各精炼工段均有损失，总损失率分别为15.01%~22.35%、11.51%~21.54%，其中生育酚主要在脱臭工段损失，损失率达10.53%~19.85%，而甾醇在中和、脱臭工段损失严重，损失率分别为5.81%~1317%、1.22%~9.18%；精炼大豆油中反式脂肪酸含量为0.761%~1.487%；3-氯丙醇酯含量在中和工段减少，在脱色工段波动，在脱臭工段明显上升，精炼大豆油中3-氯丙醇酯含量为0300~1.048 mg/kg；随着脱臭温度的降低，反式脂肪酸含量递减，生育酚和甾醇含量总体有所提升，当脱臭温度降至220 ℃时，接近零反式脂肪酸目标（

为了系统研究我国主要进口的特级初榨橄榄油性质，比较分析了我国主要进口的8种西班牙和意大利特级初榨橄榄油的脂肪酸组成、酸值、过氧化值及微量成分含量，并对其进行了挥发性成分分析及感官评价。结果表明：西班牙特级初榨橄榄油的C18∶ 1（77.22%）和C23∶ 0（0.94%）含量平均值高于意大利样品（分别为72.46%和0.64%），西班牙特级初榨橄榄油的酸值、过氧化值低于意大利样品；西班牙特级初榨橄榄油中含有γ-生育酚和δ-生育三烯酚，而意大利样品中未检出这两种，且西班牙特级初榨橄榄油中α-生育酚含量平均值（189.58 mg/kg）高于意大利样品（161.26 mg/kg），角鲨烯含量平均值（6 127.83 mg/kg）远高于意大利样品（4 083.50 mg/kg），两者甾醇含量差异很小。虽然西班牙特级初榨橄榄油的醛类含量平均值低于意大利样品，但酯类含量更高。感官评价发现，西班牙特级初榨橄榄油的果味、苦味、辣味评分皆高于意大利样品。综上，西班牙特级初榨橄榄油的酸值、过氧化值较低，α-生育酚、角鲨烯含量高于意大利样品，且感官评分较高。 In order to systematically study the properties of extra virgin olive oil mainly imported to China, the fatty acid composition, acid value, peroxide value, trace components content of eight kinds of extra virgin olive oil imported from Spain and Italy were compared and analyzed, and their volatile components analysis and sensory evaluation were carried out.The results showed that the average contents of C18∶ 1 (77.22%) and C23∶ 0 (0.94%) in Spainish extra virgin olive oil were higher than those of Italian samples (72.46% and 0.64%). The acid value and peroxide value of Spainish extra virgin olive oil were lower than those of Italian samples. γ- Tocopherol and δ- tocotrienols were detected in Spainish samples, but not detected in Italian samples, and the average α-tocopherol content(18958 mg/kg) in Spanish samples was higher than that in Italian samples (161.26 mg/kg).The average squalene content (6 127.803 mg/kg) in Spanish samples was much higher than that in Italian samples (4 083.50 mg/kg), and there was little difference in sterol content between Spanish and Italian samples. Although the average content of aldehydes in Spanish samples was lower than that in Italian samples, the content of esters was higher. Sensory evaluation showed that the fruitiness, bitterness and pungent scores of Spanish samples were higher than those of Italian samples. In conclusion, the acid value and peroxide value of Spainish samples are lower, the contents of α- tocopherol and squalene are higher than that of Italian samples, and the sensory score is higher.

The drive to achieve greater energy efficiencies is well‐established in the fine chemical industries with distillation processes being a key focus due to their disproportionate energy consumption totaling more than 40% of the overall plant. The objective of this paper is to specifically focus on the energy efficiency benefits that would be realized by employing intensified distillation column configurations on a high purity, multicomponent, high recovery industrial methanol distillation where a middle boiling trace ethanol component must be managed to ensure on specification production (<10 ppm wt. ethanol in product and <5 ppm impurities in bottoms). Based on technology maturity constraints, five column configurations were selected for further analysis, comprising a direct synthesis configuration, a side draw column, a Petlyuk inspired recovery column arrangement, a divided wall column, and a cut divided wall column. These configurations were then simulated on an industrial process simulator where all configurations were able to match the strict industrial product specifications and design limits. The energy usage of the column configurations was improved through a systematic analysis, and the results revealed that all intensified columns have a superior energy usage compared to the direct synthesis configuration but with the gains limited to only 3%. An unbiased consideration of the energy efficiency results, together with other external factors including cost of capital and operability, shows that the recovery column configuration would be the most practical choice despite the presence of the divided wall column configuration which represents a greater level of intensification and integration. [ABSTRACT FROM AUTHOR]

Abstract: The only pressurized black liquor gasifier currently in operation is located in Sweden. The composition of the main components in the gas has been reported previously. The main components are H2, CO, CO2, N2, CH4, and H2S. In the present work, trace components in the gas have been characterized and the results are hereby reported for the first time. Samples were taken at two occasions during a one year period. The benzene concentration in the gas varied only slightly and the average concentration was 158ppm. Benzene is formed by thermal cracking of the biomass. The COS concentration varied substantially and the average concentration was 47ppm. The variations may be related to how the quench is operated. A few ppm of C2-hydrocarbons were also observed in the gas and the variation was probably a result of varying oxygen to black liquor ratio. No tars were observed in the gas. However, tar compounds, such as phenanthrene, pyrene, fluoranthene and fluorene were detected in deposits found on the pipe walls after the gas cooler. The concentration of particles in the synthesis gas was very low; <0.1mg/Nm3, which is comparable to the particulate matter in ambient air. Submicron particles were comprised of elements such as C, O, Na, Si, S, Cl, K, and Ca, and these particles probably originated from the black liquor. Larger particles were comprised mainly of Fe, S and Ni and these particles probably resulted from corrosion of steel in the plant pipe-work. In summary, the concentrations of trace components and particles in the gas are quite low. [Copyright &y& Elsevier]

This study gives relevant information on the variation of concentrations of certain volatile organic compounds (BTEX, alkanes, organochlorides and terpenes) emitted by open cells receiving municipal solid waste. These compounds represent a large fraction of the total trace components present in landfill gas. The VOC measurements were carried out in the atmosphere of an open landfill cell as a function of time and meteorological parameters, but also as a function of the activity of trucks unloading waste and compaction vehicles, in order to identify the factors that influence VOC emissions. Comparisons were performed systematically between the surface of the open cell and the corresponding mechanical activity. The measurements carried out during the course of the day highlighted the influence of air temperature and waste composition on VOC emissions while measurements of activity showed that the activity of fresh waste compaction vehicles is responsible for the highest VOC emissions. Such information is essential since most of the data in the literature relate to analyses of VOC traces in the biogas network and not in the air of the open cells as a function of different parameters (i.e. meteorological parameters, activity on the site). The highest VOC concentrations (in μg/m3) in the area of an open cell were obtained for: tetrachloroethylene (9810), toluene (8230), limonene (4550), m-xylene (3980) and trichloroethylene (3680). The results showed that the TWA values (the time-weighted average concentrations for up to an 8-h workday) established by INRS/France for the personnel in the station were complied with on the site studied. [Copyright &y& Elsevier]

Abstract: When determining volatile organohalogen compounds in an aqueous matrix, specific properties of these compounds should be taken into consideration, when preparing aqueous standard solutions used for calibration and during model investigations, namely: [•] low boiling points; [•] high vapor pressure; and, [•] relatively low solubility in water. Because of the significance of this problem and the lack of practical information available in the literature, we carried out model investigations of stability of selected volatile analytes in aqueous solutions. The experimental results were used to estimate the time after which the result of determination may not reflect the true concentration of the analyte. The investigations provided information on: [•] the method of preparation of model solutions (in appropriate containers); [•] the method of storage and the storage time of these solutions; and, [•] number of repetitions needed in the final determination (repeated sampling of the solution from a volumetric flask, which requires the flask to be opened for each sampling). This parameter is especially important when determining the repeatability and the reproducibility in validating the procedure for TLHS-DAI-GC-ECD. [Copyright &y& Elsevier]

Background: Longstanding, successful use of combinations of phytopharmaceuticals in traditional Chinese medicine (TCM) has caught the attention of several pharmacologists to natural medicines. However, the development and popularisation of TCM is mainly limited because of the unavailability of reports clarifying the mechanisms of action and pharmacologically active ingredients in such formulations. Previous studies on natural medicines have mostly focused on their dominant components using forward pharmacology which often neglects trace components. It is necessary to assess the pharmacological and therapeutic superiority of many such trace components in comparison with single constituents.Purpose: In this study, we aimed to propose a new pharmacological research strategy for TCM. In particular, we presented the possibility that the effective mechanism of action of trace components of TCM is based on synthetic lethality. We sincerely hope to explore this theory further.Method: We obtained retrieve published research information related to synthetic lethality, phytochemicals and Chinese medicine from PubMed and Google scholar. Based on the inclusion criteria, 71 studies were selected and discussed in this review.Results: As an interaction among genes, synthetic lethality can amplify co-regulatory biological effects exponentially. Synthetic strategies have been successfully applied for research and development of anti-tumour agents, including poly ADP-ribose polymerase inhibitors and clinical combination of chemotherapeutic agents for efficacy enhancement and toxicity reduction. TCM drugs contain several secondary metabolites to combat environmental stresses, providing a multi-component basis for corresponding synergistic targets. Therefore, we aimed to study whether this method could be used to identify active components present in trace amounts in TCM drugs. Based on a reverse concept of target-component-effect and identified synergistic targets, we explored the mechanisms of action of weakly active components present in trace amounts in TCM drugs to assess combinations of potential synergistic components.Conclusion: This pattern of synthetic lethality not only elucidated the mechanisms of action of TCM drugs from a new perspective but also inspired future studies on discovering naturally occurring active components. [ABSTRACT FROM AUTHOR]