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Fate and degradation of nonylphenolic compounds during wastewater treatment process 被引量:2
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作者 Jing Lian Junxin Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第8期1511-1518,共8页
In order to explore the biodegradation behavior of nonylphenolic compounds during wastewater treatment processing, two full-scale wastewater treatment plants were investigated and batch biodegradation experiments were... In order to explore the biodegradation behavior of nonylphenolic compounds during wastewater treatment processing, two full-scale wastewater treatment plants were investigated and batch biodegradation experiments were conducted. The biodegradation pathways under the various operational conditions were identified from batch experiments: shortening of ethoxy-chains dominated under the anaerobic condition, whereas oxidizing of the terminal alcoholic group prevailed over the other routes under the aerobic condition. Results showed that the anoxic condition could accelerate the biodegradation rates of nonylphenolic compounds, but had no influence on the biodegradation pathway. The biodegradation rates of nonylphenol (NP) and short-chain nonylphenol polyethoxylates (NPnEOs, n: number of ethoxy units) increased from the anaerobic condition, then the anoxic, finally to the aerobic condition, while those of long-chain NPnEOs and nonylphenoxy carboxylates (NPECs) seemed similar under the various conditions. Under every operational condition, long-chain NPnEOs showed the highest biodegradation activity, followed by NPECs and short-chain NPnEOs, whereas NP showed relatively recalcitrant characteristics especially under the anaerobic condition. In addition, introducing sulfate and nitrate to the anaerobic condition could enhance the biodegradation of NP and short-chain NPnEOs by supplying more positive redox potentials. 展开更多
关键词 nonylphenolic compounds wastewater treatment process biodegradation pathways
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Polyphenolic Compound and the Degree of Browning in Processing Apple Varieties 被引量:17
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作者 SONG Ye YAO Yu-xin +3 位作者 ZHAI Heng DU Yuan-peng CHEN Feng WEI Shu-wei 《Agricultural Sciences in China》 CAS CSCD 2007年第5期607-612,共6页
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 pr... 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. 展开更多
关键词 APPLE processing varieties polyphenolic compounds BROWNING polyphenol oxidase
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Source,Process and End Treatment Technology of Volatile Organic Compounds in Oil Storage 被引量:1
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作者 Yuan Yuan Chen Tingting +1 位作者 Zhao Fengjie Sun Hui 《Meteorological and Environmental Research》 CAS 2019年第2期83-90,共8页
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 i... 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. 展开更多
关键词 OIL STORAGE VOLATILE organic compounds Whole process TREATMENT TREATMENT TECHNOLOGY
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Optimal Dividend Strategies in a Double Compound Poisson Risk Process
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作者 LI Shijun MING Ruixing HUANG Longshengt 《Wuhan University Journal of Natural Sciences》 CAS 2011年第2期133-138,共6页
In this paper, we consider a double compound Poisson risk model involving two independent classes ofinsurance risks with a threshold dividend strategy. We derived the integro-differential equations (IDE) with certai... In this paper, we consider a double compound Poisson risk model involving two independent classes ofinsurance risks with a threshold dividend strategy. We derived the integro-differential equations (IDE) with certain boundary conditions for the present value of dividends until ruin. When the claims from both classes are exponentially distributed, we show that the threshold dividend strategy is an optimal dividend strategy. 展开更多
关键词 double compound Poisson process the value function integro-differential equation threshold dividend strategy generalized Lundberg’s fundamental equation
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Treatment of pharmaceutical wastewater containing recalcitrant compounds in a Fenton-coagulation process 被引量:3
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作者 Bukuru Godefroid 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第3期459-463,共5页
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 pretreat... 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. 展开更多
关键词 pharmaceutical wastewater GC-MS recalcitrant compounds Fenton's reaction coagulation process advanced wastewater treatment
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Large Deviation Principle for a Form of Compound Nonhomogeneous Poisson Process
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作者 杨文权 胡亦钧 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期217-221,共5页
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... 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. 展开更多
关键词 large deviation principle compound Poisson process weak convergence
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IN-SITU HVEM STUDY ON PHASE TRANSITION OF YBa_2Cu_3O_(7-x) SUPERCONDUCTING COMPOUND IN PROCESS OF HEATING
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作者 王瑞坤 邸秀萱 +4 位作者 王振海 贺庆 俞定安 周和平 王英 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期99-103,共5页
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 ... 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. 展开更多
关键词 HVEM SUPERCONDUCTING compound IN process OF HEATING IN-SITU HVEM STUDY ON PHASE TRANSITION OF YBa2Cu3O Cu
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Effective technology for processing industrial volatile organic compounds by the atmospheric pressure microwave plasma torch
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作者 Da-Shuai Li Ling Tong 《Journal of Electronic Science and Technology》 EI CAS CSCD 2023年第2期87-94,共8页
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 var... 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. 展开更多
关键词 Atmospheric microwave plasma Industrial volatile organic compounds(VOCs)processing Spectroscopic diagnostic
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Empirical Likelihood Statistical Inference for Compound Poisson Vector Processes under Infinite Covariance Matrix
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作者 程从华 《Journal of Donghua University(English Edition)》 CAS 2023年第1期122-126,共5页
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 con... 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. 展开更多
关键词 compound Poisson vector process(CPVP) infinite covariance matrix domain of attraction of normal law empirical likelihood(EL)
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Measuring Tail Dependence for Aggregate Collateral Losses Using Bivariate Compound Shot-Noise Cox Process
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作者 Jiwook Jang Genyuan Fu 《Applied Mathematics》 2012年第12期2191-2204,共14页
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 ... 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. 展开更多
关键词 AGGREGATE COLLATERAL LOSSES BIVARIATE compound Cox process Shot Noise process Farlie-Gumbel-Morgenstern Copula Tail Dependence Joint Fast Fourier Transform
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Impact of Preparation Process on the Protein Structure and on the Volatile Compounds in <i>Eisenia foetida</i>Protein Powders 被引量:1
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作者 Elias Bou-Maroun Camille Loupiac +5 位作者 Aurélie Loison Bernadette Rollin Philippe Cayot Nathalie Cayot Elil Marquez Ana Luisa Medina 《Food and Nutrition Sciences》 2013年第11期1175-1183,共9页
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... 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. 展开更多
关键词 Eisenia foetida PROTEIN POWDER DRYING process PROTEIN Structure VOLATILE compounds HS-SPME/GC-MS
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Mutagenic and Estrogenic Effects of Organic Compounds in Water Treated by Different Processes: A Pilot Study
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作者 LU Yi LYU Xue Min +3 位作者 XIAO San Hua YANG Xiao Ming WANG Ya Zhou TANG Fei 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期571-581,共11页
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 ... 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. 展开更多
关键词 Water treatment processes Organic compounds Yeast estrogen screen(YES assay) Ames test GC-MS
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黄绿卷毛菇酚类物质的提取、抗氧化与降血糖活性
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作者 秦琴 朱青永 +5 位作者 杨帅 陈启和 马明珠 余佳莉 刘政捷 赵亚东 《食品工业科技》 北大核心 2026年第2期249-257,共9页
为探究黄绿卷毛菇酚类物质最佳提取工艺,分析其抗氧化和降血糖活性。本研究通过响应面试验法优化黄绿卷毛菇酚类物质最佳提取工艺,并研究了黄绿卷毛菇酚类物质的体外抗氧化、降血糖活性。结果表明:酚类物质最佳工艺为乙醇浓度48.19%,料... 为探究黄绿卷毛菇酚类物质最佳提取工艺,分析其抗氧化和降血糖活性。本研究通过响应面试验法优化黄绿卷毛菇酚类物质最佳提取工艺,并研究了黄绿卷毛菇酚类物质的体外抗氧化、降血糖活性。结果表明:酚类物质最佳工艺为乙醇浓度48.19%,料液比1:38 g/mL,超声时间35.70 min,在此条件下酚类物质得率为7.74±0.24 mg/g。对DPPH自由基清除率IC_(50)为43.85μg/mL,对ABTS+自由基清除率为7.81 mmol/g Trolox,对FRAP铁离子还原能力为1.58 mmol/g FeSO_(4)。在体外降血糖试验中,黄绿卷毛菇酚类物质对α-淀粉酶抑制率IC_(50)为2.79 mg/mL,对α-葡萄糖苷酶抑制率IC_(50)为9.85 mg/mL。综上,黄绿卷毛菇酚类物质优异的抗氧化和降血糖活性表明其具有良好开发潜力。 展开更多
关键词 黄绿卷毛菇 酚类物质 工艺优化 超声辅助提取 抗氧化 降血糖
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卤制肥肠加工过程中风味品质的动态变化研究
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作者 曲霞 李明宇 +3 位作者 尉文涵 王振宇 张德权 张春江 《核农学报》 北大核心 2026年第2期334-343,共10页
为探究卤制肥肠在预制加工过程中的挥发性风味特征及品质变化规律,本研究利用电子鼻、电子舌、顶空固相微萃取-气相色谱-质谱联用仪(HS-SPME-GC-MS)等技术进行定性、定量分析。结果表明,卤制肥肠加工过程中共鉴定出36种挥发性风味物质,... 为探究卤制肥肠在预制加工过程中的挥发性风味特征及品质变化规律,本研究利用电子鼻、电子舌、顶空固相微萃取-气相色谱-质谱联用仪(HS-SPME-GC-MS)等技术进行定性、定量分析。结果表明,卤制肥肠加工过程中共鉴定出36种挥发性风味物质,其中丙醛、1-辛烯-3-醇、乙酸乙酯、乙基麦芽酚、吲哚和丁香酚等风味化合物的气味活性值(OAV)>1,而乙基麦芽酚、丁香酚以及茴香脑的变量重要性投影(VIP)>1,表明上述风味化合物对肥肠的风味形成至关重要。进一步分析发现,吲哚类物质是卤制肥肠中的特色挥发性风味化合物,由肥肠中氨基酸的代谢产生,对肥肠特色风味的形成具有重要影响,但其含量过高时会影响产品感官品质。与卤制后的样品相比,经-35℃速冻后,卤制肥肠挥发性风味物质总含量增至1080.98μg·kg^(-1),吲哚含量显著升高,产品的肉香减弱、异味(如吲哚的粪臭味、脂肪氧化产生的酸败味)增强、口感的弹性和回复性下降。本研究揭示了卤制肥肠加工过程中风味品质形成的规律,为其工业化生产中的品质控制提供了理论支持和技术指导。 展开更多
关键词 卤制肥肠 关键工艺点 挥发性风味物质 异味物质 预制菜肴
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不同吸附剂对冷榨油茶籽油品质的影响研究
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作者 张远鹏 左宗明 +5 位作者 周奕如 王澍 殷娇娇 钟武 何东平 高盼 《粮食与油脂》 北大核心 2026年第1期18-25,共8页
对比单一及复配吸附剂对精炼油茶籽油理化特性、安全性指标及营养成分的协同效应,揭示吸附剂自身污染导致的塑化剂、苯并[a]芘(BaP)迁移风险,并发现活性炭与凹凸棒土的功能互补性。基于此,提出活性炭-凹凸棒土功能复配新工艺,经正交优... 对比单一及复配吸附剂对精炼油茶籽油理化特性、安全性指标及营养成分的协同效应,揭示吸附剂自身污染导致的塑化剂、苯并[a]芘(BaP)迁移风险,并发现活性炭与凹凸棒土的功能互补性。基于此,提出活性炭-凹凸棒土功能复配新工艺,经正交优化确定最佳条件:活性炭与凹凸棒土质量比1∶4、复配吸附剂添加量3%(以油质量计)、温度85℃、时间40 min,在此条件下成功实现安全与营养的高效平衡,BaP含量降至1.06μg/kg,酚类化合物含量为23.47 mg/kg,且酸价、过氧化值等关键指标均符合食用油标准。证明在吸附精炼工艺中复配吸附剂对油茶籽油品质具有良好的调控作用。 展开更多
关键词 油茶籽油 吸附精炼 苯并[A]芘 塑化剂 酚类化合物 复配工艺
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三七抗动脉粥样硬化药理机制研究进展
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作者 方芳 《中华中医药学刊》 北大核心 2026年第1期199-203,共5页
动脉粥样硬化(atherosclerosis,AS)是一种慢性血管炎症性疾病,是心脑血管疾病的主要病理基础。AS的发生、发展涉及炎症反应、氧化应激、脂质浸润、血管内皮细胞功能障碍、血管平滑肌细胞增殖、巨噬细胞极化、自噬稳态失衡等多种病理机... 动脉粥样硬化(atherosclerosis,AS)是一种慢性血管炎症性疾病,是心脑血管疾病的主要病理基础。AS的发生、发展涉及炎症反应、氧化应激、脂质浸润、血管内皮细胞功能障碍、血管平滑肌细胞增殖、巨噬细胞极化、自噬稳态失衡等多种病理机制。三七是我国传统的活血化瘀药物之一,临床常应用三七与多味中药配伍抗AS治疗,疗效确切。现代药理学显示,三七的活性成分主要有皂苷类、三七素、黄酮等。作为皂苷类的三七总皂苷(panax notoginseng saponins,PNS)是评价三七质量的重要指标和发挥药效的主要物质基础,含多种单体,被证实具有抗AS、改善脑缺血再灌注损伤等多种药理作用。通过对三七有效成分药理作用及其抗AS的药理机制进行分析,梳理三七临床抗AS常用复方的作用机制,探讨三七的炮制方法对其抗AS作用的影响,以期为三七更好地应用于AS的治疗及深入药理作用研究提供参考。 展开更多
关键词 三七 动脉粥样硬化 药理作用 复方 炮制
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滇红加工过程中香气品质形成研究进展
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作者 曹祖菲 娜花花 +3 位作者 文涵湘 林茂 王白娟 刘晓慧 《食品研究与开发》 2026年第1期199-206,共8页
香气是决定茶叶品质的关键因素。随着分子化学、分子生物学和代谢组学等的发展,对滇红的香气形成的研究有着长足进展,该文综述滇红茶的香气品质化学物质基础、加工工艺的影响因素和检测手段,以及当前滇红茶香气研究的局限性,以期更好地... 香气是决定茶叶品质的关键因素。随着分子化学、分子生物学和代谢组学等的发展,对滇红的香气形成的研究有着长足进展,该文综述滇红茶的香气品质化学物质基础、加工工艺的影响因素和检测手段,以及当前滇红茶香气研究的局限性,以期更好地阐明滇红茶香气品质形成的全过程,为滇红茶加工过程中香气的形成提供理论依据。 展开更多
关键词 滇红茶 香气 加工工艺 关键呈香物质 检测手段
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广泛靶向代谢组学分析不同蜜处理加工方法对小粒咖啡非挥发性化合物的影响
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作者 喻好好 付兴飞 +5 位作者 毕晓菲 李忠贤 董文江 李贵平 李亚男 胡发广 《食品工业科技》 北大核心 2026年第3期1-11,共11页
为探究不同蜜处理加工方法中非挥发性化合物的代谢差异,采用UPLC-MS/MS广泛靶向代谢组学对不同脱胶率下(CH,脱胶率100%;WH,脱胶率约80%;YH,脱胶率为40%~50%;RH,脱胶率为20%~25%;BH,脱胶率0%)的咖啡生豆进行系统分析。结果显示,在5种不... 为探究不同蜜处理加工方法中非挥发性化合物的代谢差异,采用UPLC-MS/MS广泛靶向代谢组学对不同脱胶率下(CH,脱胶率100%;WH,脱胶率约80%;YH,脱胶率为40%~50%;RH,脱胶率为20%~25%;BH,脱胶率0%)的咖啡生豆进行系统分析。结果显示,在5种不同脱胶率处理的咖啡生豆中共鉴定到1682种代谢物,多元统计分析表明脱胶率明显改变了非挥发性化合物的代谢轮廓。以VIP>1,log_(2)|FC|>1和P<0.05为阈值,筛选得到192种差异代谢物,其中氨基酸及其衍生物、有机酸、酚酸以及糖类是最主要的代谢物类别,在影响咖啡豆风味特性方面起着重要的作用。通过趋势分析,鉴定到93种非挥发性化合物的相对含量随脱胶率的降低而持续增加。京都基因与基因组百科全书(KEGG)结果显示,这些化合物在肌醇磷酸代谢、戊糖与葡萄糖酸的相互转化、半乳糖代谢、氨基糖和核苷酸糖代谢、链霉素的生物合成、吲哚生物碱生物合成以及碳水化合物消化吸收中显著富集(P<0.05)。根据最小二乘判别分析(PLS-DA)模型,确定了以N-乙酰氨基酸为主的10种潜在标志性化合物以区分不同脱胶率的蜜处理方法。研究结果揭示了咖啡果胶对咖啡豆的非挥发性化合物的影响,为通过发酵控制提升咖啡风味特性提供了理论参考。 展开更多
关键词 广泛靶向代谢组学 蜜处理法 云南小粒咖啡 非挥发性化合物
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Differences of the oxidation process and secondary organic aerosol formation at low and high precursor concentrations 被引量:4
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作者 Tianzeng Chen Yongchun Liu +6 位作者 Biwu Chu Changgeng Liu Jun Liu Yanli Ge Qingxin Ma Jinzhu Ma Hong He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第5期256-263,共8页
Current atmospheric quality models usually underestimate the level of ambient secondary organic aerosol(SOA), one of the possible reasons is that the precursors at different concentrations may undergo different oxidat... Current atmospheric quality models usually underestimate the level of ambient secondary organic aerosol(SOA), one of the possible reasons is that the precursors at different concentrations may undergo different oxidation processes and further affect SOA formation. Therefore, there is a need to perform more chamber studies to disclose the influence. In this work, SOA formation over a wide range of initial precursor concentrations(tens of ppb to hundreds of ppb levels) was investigated in a 30 m3 indoor smog chamber,and mainly through the analysis of multiple generations of VOCs detected from HR-To FPTRMS to expound the difference in the oxidation process between low and high precursor concentrations. Compared to high initial concentrations, gas-phase intermediates formed at low concentrations had a higher intensity by about one order of magnitude, and the lowvolatility compounds also had a higher formation potential due to the competition between semi-volatile intermediates and precursors with oxidants. In addition, the formed SOA was more oxidized with higher f44 value(0.14 ± 0.02) and more relevant to real atmosphere than that formed at high concentrations. This work should help to deeply understand SOA formation and improve the performance of air quality models for SOA simulation. 展开更多
关键词 Secondary organic AEROSOL AROMATIC hydrocarbons AEROSOL mass spectrometer Low-volatility compounds OXIDATION processes
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The electrochemical advanced oxidation processes coupling of oxidants for organic pollutants degradation: A mini-review 被引量:16
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作者 Jun Li Yangju Li +2 位作者 Zhaokun Xiong Gang Yao Bo Lai 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第12期2139-2146,共8页
The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different o... The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different oxidants(e.g.,persulfate(PS),peroxymonosulfate(PMS),and ozone(O3)),including EAOPs-PS systems,EAOPs-PMS systems,EAOPs-peroxone systems,and photoelectro-oxidants systems,for the organic compounds degradation.The coupling system of EAOPs with oxidants is an effective way to improve the generated free radicals(e.g.,HO^·and SO4^·-) concentration and to accelerate pollutant degradation.In this review,we make a summary of the homogeneous and heterogeneous EAOPs-oxidant processes.The reaction mechanisms of EAOPs combined with different oxidants are elucidated in detail,as well as the synergistic effect for improving the degradation and mineralization efficiency. 展开更多
关键词 Electrochemical advanced oxidation processes Organic compounds OXIDANTS Free radicals Reaction mechanism
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