Effective technology for processing industrial volatile organic compounds by the atmospheric pressure microwave plasma torch

In this study,we investigated the abatement of volatile organic compounds(VOCs)by the atmospheric pressure microwave plasma torch(AMPT).To study the treatment efficiency of AMPT,we used the toluene and water-based varnish to simulate VOCs,respectively.By measuring the compounds and contents of the mixture gas before/after the microwave plasma process,we have calculated the treatment efficiency of AMPT.The experimental results show that the treatment efficiency of AMPT for toluene with a concentration of 17.32×10^(4) ppm is up to 60 g/kWh with the removal rate of 86%.For the volatile compounds of water-based varnish,the removal efficiency is up to 97.99%.We have demonstrated the higher potential for VOCs removal of the AMPT process.

Empirical Likelihood Statistical Inference for Compound Poisson Vector Processes under Infinite Covariance Matrix

The paper discusses the statistical inference problem of the compound Poisson vector process(CPVP)in the domain of attraction of normal law but with infinite covariance matrix.The empirical likelihood(EL)method to construct confidence regions for the mean vector has been proposed.It is a generalization from the finite second-order moments to the infinite second-order moments in the domain of attraction of normal law.The log-empirical likelihood ratio statistic for the average number of the CPVP converges to F distribution in distribution when the population is in the domain of attraction of normal law but has infinite covariance matrix.Some simulation results are proposed to illustrate the method of the paper.

Polyphenolic Compound and the Degree of Browning in Processing Apple Varieties

Polyphenolic compound in processing apple （Malus domestica Borkh.） varieties and the relationship between polyphenol content and enzymatic browning were studied to provide reference for raw material selection and processing method optimization. The content of polyphenol compound in 10 processing apple varieties （4 cider and 6 juice varieties） were analyzed using the Folin-Ciocalteu method and HPLC. The degree of browning and the activities of polyphenol oxidase were also studied. The content and proportion of the polyphenol varied depending on the variety. Bitter varieties globally showed a higher polyphenol concentration than sweet or acid varieties. Proanthocyanidins, chlorogenic acid, （＋）-catechin, （-）-epicatechin were high-concentrated polyphenols in apple fruits. Phloridzin, the unique polyphenol of apple, was abundant in the bitter variety Frequin rouge fruit. Total polyphenols, proanthocyanidins, （＋）-catechin, and phloridzin had higher correlations with browning. The correlation was low between chlorogenic acid and browning. The polyphenolic profiles were correlated with the apple types. Cider apples contained more polyphenol than juice apple varieties. The content of flavan-3-ol has a close relationship with fruit browning.

Source,Process and End Treatment Technology of Volatile Organic Compounds in Oil Storage

Oil storage is a source of volatile organic compounds( VOCs). Volatile organic compounds can cause different damages to the environment,animals and plants. Therefore, it is important to control the discharge of VOCs in oil storage. In this paper,the control technology of sources of VOCs pollution in oil storage was analyzed from the source,process and end treatment,and measures for the prevention and control of VOCs pollution in oil storage were proposed.

Large Deviation Principle for a Form of Compound Nonhomogeneous Poisson Process

By the Cramér method, the large deviation principle for a form of compound Poisson process S(t)=∑N(t)i=1h(t-Si)Xi is obtained,where N(t), t>0, is a nonhomogeneous Poisson process with intensity λ(t)>0, Xi, i≥1, are i.i.d. nonnegative random variables independent of N(t), and h(t), t>0, is a nonnegative monotone real function. Consequently, weak convergence for S(t) is also obtained.

Treatment of pharmaceutical wastewater containing recalcitrant compounds in a Fenton-coagulation process

The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreated by UASB （upflow anaerobic sludge bed） and a SBR （sequencing batch reactor） process. The residual recalcitrant compounds, measured by gas chromatographymass spectrometry （GC-MS）, mainly consisted of alcohols, phenols, and nitrogenous and sulfur compounds. The experimental results indicated that when the Fenton＇s reaction was conducted at pH=3.0, H2O2CODOcr=0.27, H2O2/Fe^2＋=3：1 and 30 min of reaction time, and the coagulation process operated at a sulfate aluminum concentration of 800 mg/L and pH value of 5.0, the color and COD in the wastewater decreased by 94% and 73%, respectively; with a finale COD concentration of 267 mg/L and color level of 40 units, meeting the secondary standard of GB8978-1996 for industrial wastewater.

IN-SITU HVEM STUDY ON PHASE TRANSITION OF YBa_2Cu_3O_(7-x) SUPERCONDUCTING COMPOUND IN PROCESS OF HEATING

In-situ HVEM observation on phase transition of the YBa_2Cu_3O_(7-x) superconducting compound in pro- cess of heating was carried out,and high temperature X-ray diffraction analysis in air and X-ray diffraction phase analysis for the sample treated in vacuum condition were made.The results showed that the temperature of phase transition is related to oxygen content in the sample and in general,is 100℃ to 120℃ lower in vacu- um condition than in air.At 320℃ to 350℃ twin bands begin to disappear,and some Cu_2O are formed on the surface of the sample and transit from orthorhombic YBa_2Cu_3O_(7-x) to arthorhombic Y_2BaCuO_5 compound. This transition was completed at about 500℃.Above 900℃,this compound consists of the Y_2BaCuO_5, BaCuO_2,Y_2O_3 and some other minor compounds.No phase transition was observed during cooling the sample.

Measuring Tail Dependence for Aggregate Collateral Losses Using Bivariate Compound Shot-Noise Cox Process

In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used to count collateral losses. A homogeneous Poisson process is also examined as its counterpart for the case where the catastrophic loss frequency rate is deterministic. Joint Laplace transform of the distribution of the aggregate collateral losses is derived and joint Fast Fourier transform is used to obtain the joint distributions of aggregate collateral losses. For numerical illustrations, a member of Farlie-Gumbel-Morgenstern copula with exponential margins is used. The figures of the joint distributions of collateral losses, their contours and numerical calculations of risk measures are also provided.

Mutagenic and Estrogenic Effects of Organic Compounds in Water Treated by Different Processes: A Pilot Study

Objective In this study, a pilot-scale investigation was conducted to examine and compare the biotoxicity of the organic compounds in effluents from five treatment processes (P1-P5) where each process was combination of preoxidation (O3), coagulation, sedimentation, sand filtration, ozonation, granular activated carbon, biological activated carbon and chlorination (NaClO). Methods Organic compounds were extracted by XAD-2 resins and eluted with acetone and dichlormethane (DCM). The eluents were evaporated and redissolved with DMSO or DCM. The mutagenicity and estrogenicity of the extracts were assayed with the Ames test and yeast estrogen screen (YES assay), respectively. The organic compounds were detected by GC-MS. Results The results indicated that the mutation ratio (MR) of organic compounds in source water was higher than that for treated water. GC-MS showed that more than 48 organic compounds were identified in all samples and that treated water had significantly fewer types and concentrations of organic compounds than source water. Conclusion To different extents, all water treatment processes could reduce both the mutagenicity and estrogenicity, relative to source water. P2, P3, and P5 reduced mutagenicity more effectively, while P1 reduced estrogenicity, most effectively. Water treatment processes in this pilot plant had weak abilities to remove Di-n-butyl phthalate or 1, 2-Benzene dicarboxylic acid.

即食乌龙头黄花菜复合食品加工工艺研究

为延申乌龙头和黄花菜的产业链和综合利用,优化乌龙头黄花菜复合食品的品质,以新鲜乌龙头和黄花菜为主要原料,以食用植物油、食盐、白砂糖、香辛料为调味料,通过单因素试验确定调味料的种类和添加量,通过正交试验确定乌龙头黄花菜复合食品调味料的配比。正交试验结果表明,食盐添加量1.4%、香辛料添加量0.45%、白砂糖添加量4%、食用植物油添加量9%时可制得色泽诱人、口感鲜嫩香脆、乌龙头甘醇味浓、营养丰富的乌龙头黄花菜复合食品,其感官评分为98.47分。该生产工艺和方法合理,安全可靠,值得推广。

Impact of Preparation Process on the Protein Structure and on the Volatile Compounds in <i>Eisenia foetida</i>Protein Powders

Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above 42°C. Protein solubility was also studied. The addition of dissociating reagents allowed concluding that solubility was decreased during oven drying due to thermo denaturation including hydrogen bonds. The volatile compounds of the different powders were extracted by solid phase micro-extraction and identified by mass spectrometry. Volatile compounds were related to lipid oxidation and Maillard reactions occurring during the preparation of the powders. High drying temperatures led to more volatile compounds resulting from Maillard reactions. In the protein powder preparation process, a fractionation step led to a “pulp fraction” and a “juice fraction” of earthworms. The “pulp fraction” contained less odorant volatile compounds resulting from Maillard reactions than the “juice fraction” did.

复合益生菌固态发酵断奶仔猪配合饲料工艺参数的优化及品质评定

利用复合益生菌联合发酵技术对断奶仔猪配合饲料进行固态厌氧发酵,通过不同的工艺参数:接菌量、发酵温度、发酵水分和发酵时间,探讨对发酵饲料品质的影响。结果显示:不同的参数对配合饲料品质有明显影响。采用5.0%接种量、35%发酵水分、37℃发酵温度和72 h发酵时间,可有效提高配合饲料中粗蛋白、乳酸、游离氨基酸的含量和益生菌数量,降低发酵饲料霉菌数量,改善发酵饲料风味和品质,防止饲料霉变和虫蛀。发酵后的配合饲料颜色金黄、气味芳香、质地松散而不黏连。

加工方式对大豆油中挥发性物质的影响

为探究加工方式对大豆油风味物质的影响,采用电子鼻与顶空固相微萃取-气相色谱-质谱联用相结合的方法分析浸提、热榨和冷榨3种方式加工的大豆油挥发性物质的差异。结果表明:在3种大豆油样品中共检出86种挥发性物质,其中浸提油53种,热榨油54种,冷榨油45种,主要包括醛类、醇类、酮类、酸类、酯类、萜烯类、杂环类(呋喃和吡嗪)以及烃类等化合物。在3种大豆油中检出相同的挥发性物质有24种。主成分分析和层次聚类分析结果表明加工方式对大豆油风味的影响较大。采用气味活度值(OAV)判定3种大豆油样品的关键风味物质,浸提油中检出关键风味物质15种,以3-壬烯-2-酮等物质为主,使浸提油具有浆果风味。热榨油中检出关键风味物质16种,其中2,5-二甲基吡嗪等杂环类物质使热榨油具有独特的烘焙风味。冷榨油中检出12种关键风味物质,以(E,E)-2,4-庚二烯醛等醛类物质为主,使冷榨油具有天然油脂风味。偏最小二乘回归分析表明电子鼻与气相色谱-质谱联用的检测结果间存在较好相关性。

基层疾病预防控制机构复合型人才评价指标体系构建

目的 构建基层疾病预防控制机构复合型人才评价指标体系,为基层疾控机构评价复合型人才提供参考。方法 根据冰山模型理论、德尔菲法和层次分析法,对甄选的专家进行咨询和问卷调查,计算各评价指标的权重并排序,建立基层疾控机构复合型人才评价指标体系。结果 共进行两轮专家咨询,协调系数分别为0.633和0.743,建立7个一级指标、17个二级指标在内的基层疾控机构复合型人才评价指标体系,符合一致性检验要求。一级指标分别为人员基本情况、学识水平、专业知识与技能、学习与创新能力、组织力与执行力、沟通协作能力、抗压能力与特殊成就,权重分别为0.083 01、0.089 03、0.093 79、0.125 30、0.223 08、0.205 30和0.180 49。其中二级指标位列前3位为处理疫情及重大事件能力、团队意识及协作能力、现任岗位工作能力。结论 基层疾控机构复合型人才评价工作中评价权重应向组织力与执行力指标倾斜,沟通协作能力指标也应给予重视;研究指标具有一定的科学性和实用性,为基层疾病预防控制机构选拔人才提供参考。

功率器件封装用Cu-Sn全IMC接头制备及其可靠性研究进展

随着功率半导体器件的服役环境越来越恶劣,以碳化硅(SiC)为代表的第三代半导体凭借其优异的高温性能成为行业应用主流。但目前尚缺乏与之相匹配的低成本、耐高温的互连材料,成为了制约行业发展的瓶颈。Cu-Sn全金属间化合物(IMC)因其成本低、导电性好且满足低温连接、高温服役的特点被认为是理想的SiC芯片互连材料之一。针对功率半导体器件封装,对国内外近年来Cu-Sn全IMC接头的制备方法和可靠性进行了分析和综述,并讨论了目前亟待解决的问题和未来的发展趋势。

基于GC-IMS技术分析五种市售不同工艺油莎豆油理化品质与风味差异

为研究市售不同工艺油莎豆油理化品质与风味的差异性,采用气相离子迁移谱(Gas Chromatography-Ion Mobility Spectroscopy,GC-IMS)技术结合主成分分析法对比不同工艺(物理压榨、热榨、亚临界萃取、高压冷榨和冷榨工艺)油莎豆油挥发性化合物之间的差异性。GC-IMS结果显示,不同工艺油莎豆油中共鉴定出76种挥发性化合物,其中包括酯类12种、醇类16种、醛类29种、酮类9种、酸类5种、呋喃类3种、吡嗪类1种、硫类1种。热榨组醛类、酯类和呋喃类物质相对含量较高(53.54%,13.06%,5.41%)。不同工艺油莎豆油风味差异性主要来源于四种关键风味物质:1-烯-3-辛醇、壬醛、(E)-2-辛烯醛和己醛。主成分分析(Principal Component Analysis,PCA)结果表明PC1和PC2分别为48.7%和30.1%,累计差异贡献率为78.8%,不同工艺油莎豆油风味物质差异显著,能够对不同工艺油莎豆油良好区分。Pearson相关性分析结果表明不同工艺油莎豆油b*值与酸价、过氧化值、p-丙二醛值和1-烯-3-辛醇之间呈显著正相关(0.57<r<0.88,P<0.05)。本研究结对市售油莎豆油生产加工、理论研究和质量检测等领域具有一定的参考价值。

果品挥发性风味物质的研究进展

水果是居民膳食的重要组成部分,挥发性风味物质是评价果实品质的重要指标之一,对果实的整体风味和消费者的接受程度都有很大的影响。研究水果中挥发性风味物质的组成和含量,对于鲜果贮藏及其加工市场都具有重要意义。该文介绍水果中挥发性风味物质的常用提取方法与分析技术,总结水果在贮藏和加工过程中挥发性风味物质的变化,并对未来水果挥发性风味物质的研究方向进行展望。

浸渍方式对高海拔‘赤霞珠’葡萄酒挥发性风味物质的影响

以我国西南高山葡萄酒产区的‘赤霞珠’葡萄为原料,采用不同浸渍方式进行酿造,通过对葡萄酒理化指标和挥发性香气成分进行检测分析,明确浸渍方式对高海拔葡萄酒挥发性香气品质的影响。结果表明,发酵后延长浸渍处理的酒样具有更高的可滴定酸、酒精度、残糖和总酚含量;不同浸渍处理下酒样的挥发性物质中均以醇类和酯类物质含量较高,但处理间风味物质组成差异较大;发酵前冷浸渍处理酒样的风味物质最多,达到61种,其主要差异化合物为异戊醇、正己醇和苯乙醇等具有花香和青草香的醇类化合物;发酵后延长浸渍处理酒样的差异化合物种类更加丰富,且以呈甜果香的乙酸乙酯等酯类化合物含量更高。感官评价结果表明,与常规浸渍发酵相比,发酵前冷浸渍和发酵后延长浸渍处理的酒样呈现出更强的花果香和香料味,且发酵后延长浸渍处理酿造的葡萄酒具有更浓郁的果香和更复杂的风味结构。本研究结果为优化我国高海拔地区优质葡萄酒的酿造工艺提供了一定的参考。

新型橡杜复合改性沥青的制备参数研究

为改善橡胶沥青的高温性能和储存稳定性能,基于具有橡塑二重性的可再生资源——杜仲胶对橡胶沥青的改性增强机理,以沥青常规性能试验和微观观测为手段,研究了杜仲胶与橡胶粉反应时间和温度、橡杜复合改性剂掺量对橡杜复合改性沥青(REMA)性能的影响,提出了最佳制备工艺。结果表明:杜仲胶能够显著改善橡胶沥青的性能,REMA具有很好的施工和易性和储存稳定性;改性剂掺量对REMA的性能有显著的影响,杜仲胶和橡胶粉反应时间对REMA影响较大,杜仲胶和橡胶粉反应温度对REMA影响较小。结合宏观性能试验结果和微观检测分析,制备REMA的最佳工艺参数为:杜仲胶和橡胶粉反应时间为1.0~1.5 h,杜仲胶和橡胶粉反应温度为170~180℃,橡杜复合改性剂掺量为基质沥青质量的20%~25%。

不同预处理和干燥方式下养心菜粉色泽、功能成分和抗氧化性水平的比较

为了研究养心菜的加工适用性,拓展其利用途径,采用未预处理(Untreated,UT)、沸水漂烫(Boiling Water Blanching,BWB)、沸水+护色漂烫(COLOR Protection+Water Blanching,CPB)、蒸汽漂烫(Steam Blanching,SB)与冻融(Freeze-Thawing,FT)五种预处理方式处理后,分别进行热风干燥(Hot Air Drying,HA)、热泵干燥(Heat Pump Drying,HP),得到UT HP、UT HA、BWB HP、BWB HA、CPB HP、CPB HA、SB HP、SB HA、FT HP及FT HA 10种养心菜粉,比较不同预处理方式和干燥方式下养心菜色泽、功能成分及抗氧化能力水平的变化。结果表明:UT HP没食子酸和山萘酚含量最高,但色泽差、叶绿素含量较低,干燥时间长;CPB HP的干燥时间短,Vc含量最高,具有较高的抗氧化水平,但没食子酸含量较低;SB HP总酚、总黄酮、槲皮素含量最高,其他品质指标介于中间;FT HP养心菜具有最好的色泽、最高的叶绿素、游离氨基酸含量,但总酚、总黄酮、槲皮素、山萘酚以及抗氧化水平低。从主成分分析来看,BWB HP、CPB HP、SB HP和BWB HA、CPB HA、SB HA的养心菜品质分别具有一定的相似性,UT HP、FT HP、UT HA、UT HA和其有明显差异。该文综合比较了养心菜不同预处理及干燥方法的优劣,在养心菜下游的功能性食品的开发过程中,可以根据需求选择合适的干燥方法。