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Correlation between dominant bacterial community and non-volatile organic compounds during the fermentation of shrimp sauces 被引量:3
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作者 Ruichang Gao Huijie Liu +3 位作者 Ying Li Hongying Liu Yue Zhou Li Yuan 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期233-241,共9页
Shrimp sauce,one of the traditional salt-fermented food in China,has a unique flavor that is influenced by the resident microflora.The quality of salt-fermented shrimp sauce was evaluated in this work by determining t... Shrimp sauce,one of the traditional salt-fermented food in China,has a unique flavor that is influenced by the resident microflora.The quality of salt-fermented shrimp sauce was evaluated in this work by determining the total volatile basic nitrogen(TVB-N),the amino acid nitrogen(AAN),organic acid,5’-nucleotide and free amino acids(FAA).Moreover,the dynamics of microbial diversity during processing was investigated by using high-throughput sequencing technology.The results showed that the AAN,TVB-N,organic acid,5’-nucleotide and FAA content were in range of 0.93-1.42 g/100 mL,49.91-236.27 mg/100 mL,6.65-20.68 mg/mL,3.51-6.56 mg/mL and 81.27-102.90 mg/mL.Among the microbial diversity found in the shrimp sauce,Tetragenococcus,Flavobacterium,Polaribacter,Haematospirillum and Staphylococcus were the predominant genera.Correlation analysis indicated that the bacteria Tetragenococcus and Staphylococcus were important in the formation of non-volatile compounds.Tetragenococcus positively correlated with a variety of FAAs;Staphylococcus positively correlated with 5’-nucleotides.The analysis indicated that Tetragenococcus and Staphylococcus were the core genera affecting non-volatile components.These findings indicate the dynamics of the bacterial community and non-volatile components inter-relationships during shrimp sauce fermentation and provide a theoretical basis for improving the fermentation process of shrimp sauce. 展开更多
关键词 Shrimp sauces Non-volatile compounds Bacterial community Electronic tongue correlation analysis
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Volatile Compounds Selection via Quantile Correlation and Composite Quantile Correlation: A Whiting Case Study 被引量:1
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作者 Ibrahim Sidi Zakari Assi N’guessan +1 位作者 Alexandre Dehaut Guillaume Duflos 《Open Journal of Statistics》 2016年第6期995-1002,共9页
The freshness and quality indices of whiting (Merlangius merlangus) influenced by a large number of chemical volatile compounds, are here analyzed in order to select the most relevant compounds as predictors for these... The freshness and quality indices of whiting (Merlangius merlangus) influenced by a large number of chemical volatile compounds, are here analyzed in order to select the most relevant compounds as predictors for these indices. The selection process was performed by means of recent statistical variable selection methods, namely robust model-free feature screening, based on quantile correlation and composite quantile correlation. On the one hand, compounds 2-Methyl-1-butanol, 3-Methyl-1-butanol, Ethanol, Trimethylamine, 3-Methyl butanal, 2-Methyl-1-propanol, Ethylacetate, 1-Butanol and 2,3-Butanedione were identified as major predictors for the freshness index and on the other hand, compounds 3-Methyl-1-butanol, 2-Methyl-1- butanol, Ethanol, 3-Methyl butanal, 3-Hydroxy-2-butanone, 1-Butanol, 2,3-Butane- dione, 3-Pentanol, 3-Pentanone and 2-Methyl-1-propanol were identified as major predictors for the quality index. 展开更多
关键词 Volatile compounds Freshness and Spoilage Indices Quantile correlation Composite Quantile correlation Sure Independence Screening
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Comprehensive lipidomics and volatile compounds profiling reveals correlation of lipids and flavors in DHA-enriched egg yolk
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作者 Nian Wang Jie Wang +6 位作者 Yao Zhang Zongyuan Wu Dan Wang Huaming Xiao Xin Lyu Hong Chen Fang Wei 《Oil Crop Science》 CSCD 2023年第1期27-34,共8页
DHA-enriched eggs have gained popularity due to their unique nutritional value,but their flavor can be challenging for some consumers to accept.The study analyzed the correlation of lipids and flavors in DHA-enriched ... DHA-enriched eggs have gained popularity due to their unique nutritional value,but their flavor can be challenging for some consumers to accept.The study analyzed the correlation of lipids and flavors in DHA-enriched egg yolks using comprehensive lipidomics and volatile compound analysis.The results showed that 411 lipids were detected in two egg yolk samples.Among them,148 lipid species,including 48 DHA-containing lipids,were significantly higher in DHA-enriched egg yolks than in Common ones(P<0.05).Furthermore,of the 24 volatile compounds detected,the contents of benzaldehyde,heptanal,hexanal,decanal and 2-nonanone in DHA-enriched egg yolks were significantly higher than in Common egg yolks(P<0.05).The“fishy”smell characteristic of DHAenriched egg yolks was mainly caused by volatile aldehydes,which may be produced through the hydrolysis of lipids in the egg yolk to free fatty acids and further oxidation.Analysis of the correlation network diagram revealed that phospholipids containing docosahexaenoic acid(DHA),linoleic acid,or oleic acid chains were the main contributors to the characteristic flavor of DHA-enriched egg yolks.Overall,this study explored the effect of different lipids on the flavor of DHA-enriched egg yolks and provided a theoretical basis for the production and improvement of DHA-enriched eggs. 展开更多
关键词 DHA-Enriched egg yolk LIPIDOMICS DHA-Lipids Volatile compounds correlation analysis
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Oil-source rock correlation and quantitative assessment of Ordovician mixed oils in the Tazhong Uplift, Tarim Basin 被引量:11
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作者 Li Sumei Pang Xiongqi +2 位作者 Zhang Baoshou Xiao Zhongyao Gu Qiaoyuan 《Petroleum Science》 SCIE CAS CSCD 2010年第2期179-191,共13页
The origin of the marine oils in the Tarim Basin has long been a disputed topic. A total of 58 DST (drill stem test) crude oil and 8 rock samples were investigated using a comprehensive geochemical method to charact... The origin of the marine oils in the Tarim Basin has long been a disputed topic. A total of 58 DST (drill stem test) crude oil and 8 rock samples were investigated using a comprehensive geochemical method to characterize and identify the origin of the Ordovician oils in the Tazhong Uplift, Tarim Basin, northwest China. Detailed oil–oil and oil–source rock correlations show that the majority of the oils have typical biomarker characteristics of the Middle-Upper Ordovician (O2+3) source rock and the related crude oil. These characteristics include a distinct "V-shaped" relative abundance of C27, C28 and C29 regular steranes, low abundance of dinosterane, 24-norcholestanes, triaromatic dinosteroids and gammacerane. Only a few oils display typical biomarker characteristics indicating the Cambrian–Lower Ordovician (∈-O1) genetic affinity, such as linear or anti "L" shape distribution of C27, C28 and C29 regular sterane, with relatively high concentrations of dinosterane, 24-norcholestanes, triaromatic dinosteroids and gammacerane. It appears that most of the Ordovician oils in the Tazhong Uplift were derived from the O2+3 intervals, as suggested by previous studies. However, the compound specific n-alkane stable carbon isotope data indicate that the Ordovician oils are mixtures from both the ∈-O1 and O2+3 source rocks rather than from the O2+3 strata alone. It was calculated that the proportion of the∈-O1 genetic affinity oils mixed is about 10.8%-74.1%, with an increasing trend with increasing burial depth. This new oil-mixing model is critical for understanding hydrocarbon generation and accumulation mechanisms in the region, and may have important implications for further hydrocarbon exploration in the Tarim Basin. 展开更多
关键词 BIOMARKER compound specific isotope oil–source rock correlation mixed oil
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Effect of pressure cooking on phenolic compounds of quinoa 被引量:1
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作者 Qianwei Ma Zhixiang Li +2 位作者 Thanutchaporn Kumrungsee Wenda Huang Ruge Cao 《Grain & Oil Science and Technology》 CAS 2023年第3期127-134,共8页
Due to good nutritional properties and potential health benefits,quinoa has gained an increasing attention.The study aimed to analyze the effect of pressure cooking on the composition,antioxidant activity,antibacteria... Due to good nutritional properties and potential health benefits,quinoa has gained an increasing attention.The study aimed to analyze the effect of pressure cooking on the composition,antioxidant activity,antibacterial activity and bioavailability of phenolic compounds in four types of quinoa,and to evaluate the correlation between phenolics and its biological activities by correlation analysis.The results showed that different varieties of quinoa contained different phenolic components and their biological activities were different.Pressure cooking could significantly increase(P<0.05)the phenolic contents of quinoa,and decrease in vitro digestibility of protein.The antioxidant activity,antibacterial activity and bioavailability of quinoa were also enhanced which were positively related with phenolic contents.HPLC analysis indicated that at least twelve phenolic compounds were found in quinoa,and hyperoside,sinapic acid,rutin and ferulic acid occupied a majority of them.Correlation analysis suggested that hyperoside,quercetin,sinapic acid,ferulic acid and gallic acid made the key contribution to antioxidant and antibacterial activities of phenolic compounds of quinoa.The results provided valuable information for quinoa processing with phenolics as functional ingredient. 展开更多
关键词 QUINOA Pressure cooking Phenolic compounds Bioactivity correlATION
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Influence of Reactive Volatile Organic Compounds on Ozone Production in Houston-Galveston-Brazoria Area
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作者 Samarita Sarker Raghava R. Kommalapati Ziaul Huque 《Journal of Environmental Protection》 2015年第4期399-408,共10页
Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-... Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-attainment area for ozone (O3). A summer episode of May 28 to July 2, 2006 is simulated using Comprehensive Air Quality Model with extensions (CAMx). During this period O3 concentration in HGB often exceeds the National Ambient Air Quality Standards (NAAQS) 0.075 ppm of average 8 hour O3 concentration. HGB area has numerous point sources. Various studies found that some specific volatile organic compounds are very reactive in atmosphere. The objective of this study is to analyze the influence of volatile organic compounds present in point source emissions on the air quality of HGB area. For this purpose ozone sensitivity for HGB area is analyzed by the ratio of hydrogen peroxides (H2O2) to nitric acid (HNO3). HGB area is found NOx limited but reactive VOCs are found to be influential too. From (1-4 June, 2006) maximum O3 concentration was found on weekend, June 3. VOCs such as Acetaldehyde (ALD2), Formaldehyde (FORM) and Alkane (ETHA) showed good correlation with O3 concentrations on that day. In addition, Peroxyacetyl nitrate (PAN) formation was found correlated to higher ozone production. Criteria pollutant Sulfur dioxide (SO2) was found to influence the ALD2 and ETHA concentrations, and thus indirectly influenced O3 production. 展开更多
关键词 Comprehensive Air Quality Model with Extensions (CAMx) Nitrogen Oxides (NOx) Ozone (O3) VOLATILE Organic compound (VOC) correlation of VOC with O3
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Resolution of Suspected Tank Release of Diesel Fuel Using Diagnostic Compounds and Biomarkers
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作者 Jun Lu Deborah Dees Kowalewski 《Journal of Environmental Protection》 2016年第3期473-480,共8页
During a routine inspection in a petroleum product terminal, hydrocarbon staining was found in soil along the perimeter of a diesel fuel tank. As the observation was made a few days after a magnitude 5.1 earthquake in... During a routine inspection in a petroleum product terminal, hydrocarbon staining was found in soil along the perimeter of a diesel fuel tank. As the observation was made a few days after a magnitude 5.1 earthquake in the general area of the terminal, the hydrocarbon staining in the soil was suspected to be a result of a leak from the tank. The observation triggered an immediate tank inspection, which included examination of tank exterior, piping and connections;pressure testing;wall thickness gauging;and an inventory check. Results of the initial inspection suggested that there were no integrity issues with the tank. Before more vigorous and more disruptive inspections were conducted, chemical fingerprinting was conducted to assess the nature of soil staining and potential connection with the “suspected” tank leak. Samples were collected from the site, including a diesel fuel sample from the tank, a light non-aqueous phase liquid (LNAPL) sample from the monitoring well in the immediate vicinity, and representative soil samples from the perimeter of, and beneath, the tank. A tiered laboratory analytical approach was taken, which included initial gas chromatography-flame ionization detector carbon chain analysis and final gas chromatography-mass spectrometry or detailed fingerprint analyses. Based on the results of initial inspection, knowledge of LNAPL mobility in response to earthquake seismic waves, and chemical fingerprints of representative samples, it was determined that the soil staining was not a result of suspected tank release but remobilization of hydrocarbons from the historically impacted soil beneath the tank to the soil along the perimeter of the tank. 展开更多
关键词 Tank Leak Seismic Wave LNAPL Mobility Diagnostic compounds Biomarkers Source Identification and correlation
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废弃葡萄枝条复配基质栽培果类蔬菜配方筛选
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作者 马丽娟 魏锋 +2 位作者 张亚红 葛静 周娟 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第2期136-145,共10页
【目的】通过对葡萄枝条堆肥化处理形成复配基质并栽培果类蔬菜,筛选出适合果菜生长发育的最佳基质配方,为废弃葡萄枝条循环利用提供理论依据。【方法】比较发酵后的葡萄枝条、草炭和珍珠岩3者体积比为20∶50∶30(T_(1))、30∶40∶30(T_... 【目的】通过对葡萄枝条堆肥化处理形成复配基质并栽培果类蔬菜,筛选出适合果菜生长发育的最佳基质配方,为废弃葡萄枝条循环利用提供理论依据。【方法】比较发酵后的葡萄枝条、草炭和珍珠岩3者体积比为20∶50∶30(T_(1))、30∶40∶30(T_(2))、40∶30∶30(T_(3))、50∶20∶30(T_(4))和商品基质(CK)的理化性质,测定在不同基质配比下种植3种果菜(黄瓜、茄子、番茄)的生长特性和品质指标,并对各指标进行相关性分析。【结果】不同基质理化性质均在果菜生长发育的适宜范围。与CK相比,黄瓜和茄子的T_(3)产投比差值为0.64和0.38;番茄的T_(4)产投比差值为3.02。典型晴天T_(3)和CK的基质温度日较差分别为6.01℃和5.75℃;典型阴天T_(4)基质平均温度较CK高1.17℃。3种果菜的生长及品质指标与基质特性相关性达到显著或极显著水平,其中黄瓜的生长及品质指标与基质全磷含量相关性最高,茄子与基质电导率(EC)值相关性最高,番茄与基质速效氮相关性最高。【结论】黄瓜和茄子在T_(3)处理下生长发育较好,番茄在T_(4)处理下生长发育较好。T_(3)和T_(4)处理的复配基质可作为废弃葡萄枝条栽培化的推荐配方,为葡萄园废弃物再利用提供新途径。 展开更多
关键词 葡萄枝条 复配基质 相关性 配方筛选 果类蔬菜
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鄂尔多斯盆地大牛地气田上古生界致密气轻烃地球化学特征
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作者 倪春华 吴小奇 +5 位作者 王萍 王付斌 贾会冲 朱建辉 张毅 姜海健 《石油实验地质》 CAS CSCD 北大核心 2024年第2期366-379,共14页
大牛地气田是鄂尔多斯盆地典型致密砂岩大气田之一。为了更深入了解该区天然气的成因和来源,揭示天然气运移相态,对大牛地气田上古生界致密气开展了轻烃地球化学特征分析。研究表明,该区上古生界致密气C5-7轻烃组成具有异构烷烃优势分布... 大牛地气田是鄂尔多斯盆地典型致密砂岩大气田之一。为了更深入了解该区天然气的成因和来源,揭示天然气运移相态,对大牛地气田上古生界致密气开展了轻烃地球化学特征分析。研究表明,该区上古生界致密气C5-7轻烃组成具有异构烷烃优势分布,C6-7轻烃组成中芳烃含量整体偏低(<10%),甚至未检出芳烃,C7轻烃组成具有甲基环己烷优势分布特征,甲基环己烷相对含量均超过50%。上二叠统下石盒子组天然气K_(1)值、K_(2)值均与二叠系山西组和石炭系太原组天然气一致,而δ^(13)C_(1)值则与山西组天然气一致,与太原组天然气有明显不同。与山西组天然气相比,下石盒子组天然气整体具有偏低的苯/正己烷、苯/环己烷和甲苯/正庚烷比值,以及明显偏高的正庚烷/甲基环己烷比值。轻烃地球化学特征及烷烃气碳氢同位素组成综合表明,大牛地气田上古生界天然气为典型煤成气,其中山西组和太原组天然气均为原地自生自储,而下石盒子组天然气为下伏山西组烃源岩生成的天然气经历了游离相垂向运移聚集形成,太原组烃源岩不具有显著贡献。受天然气运移和水溶等作用影响,庚烷值、异庚烷值、苯/正己烷比值等轻烃指标直接用于判识大牛地气田致密气成熟度会存在偏差。 展开更多
关键词 轻烃化合物 成熟度 天然气成因 气源对比 运移相态 大牛地气田 鄂尔多斯盆地
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应力波作用下红砂岩复合动态断裂特征研究
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作者 解北京 李晓旭 +3 位作者 栾铮 陈思羽 陈铭进 梁天宇 《矿业科学学报》 CSCD 北大核心 2024年第1期42-52,共11页
为探究应力波作用下红砂岩的复合动态断裂特性,采用分离式霍普金森压杆和数字图像技术对带预制裂缝的半圆盘三点弯曲试样开展冲击加载实验,分析加载率、波长对红砂岩动态拉伸、断裂特征的影响。结果表明:①红砂岩试样加载率与动态抗拉... 为探究应力波作用下红砂岩的复合动态断裂特性,采用分离式霍普金森压杆和数字图像技术对带预制裂缝的半圆盘三点弯曲试样开展冲击加载实验,分析加载率、波长对红砂岩动态拉伸、断裂特征的影响。结果表明:①红砂岩试样加载率与动态抗拉强度、断裂韧度及破坏率均呈一次函数关系;断裂能随加载率增大而增长415.27%。②随着波长增加,动态抗拉强度增长742.14%,其中断裂能增长54.49%,但能量吸收率呈下降趋势;裂纹扩展平均速度增长4.09%,且首尾裂纹应变增长时间出现滞后现象;破坏率增长效应得到强化。③冲击速度8 m/s时试件主裂纹首尾监测点位的应变平均增加84.31%。 展开更多
关键词 分离式霍普金森杆 半圆盘三点弯曲 应力波 复合断裂 数字图像相关
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现代工艺六堡茶渥堆过程中茶汤色泽及主要滋味品质成分动态变化 被引量:3
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作者 许皓 肖虹菲 +5 位作者 林家威 欧行畅 欧阳建 黄甜 刘仲华 黄建安 《食品与发酵工业》 CAS CSCD 北大核心 2024年第11期317-326,共10页
通过对现代工艺六堡茶渥堆过程样品进行感官审评及电子舌、色差、主要生化成分测定,研究六堡茶渥堆过程中色泽及滋味成分的变化规律,并探讨了滋味属性的变化与滋味成分之间的相关性及滋味活度值(taste active value,TAV)。结果表明,现... 通过对现代工艺六堡茶渥堆过程样品进行感官审评及电子舌、色差、主要生化成分测定,研究六堡茶渥堆过程中色泽及滋味成分的变化规律,并探讨了滋味属性的变化与滋味成分之间的相关性及滋味活度值(taste active value,TAV)。结果表明,现代工艺渥堆过程中,六堡茶酸味、苦味上升,涩味、鲜味及咸味下降,色差L值波动变化,a、b值逐渐升高,汤色由黄转变为橙红,游离氨基酸、黄酮、茶多酚、茶叶碱、儿茶素总量、氨基酸组分总量显著下降(P<0.05),可可碱、咖啡碱、没食子酸显著上升(P<0.05),水浸出物含量呈波动变化。游离氨基酸、黄酮、酯型儿茶素、DL-儿茶素(DL-catechin, DL-C)及部分氨基酸组分与酸味和苦味显著负相关,与涩味、鲜味及咸味显著正相关,咖啡碱与没食子酸则相反;茶多酚与涩味显著正相关。咖啡碱、可可碱、没食子酸、DL-C及酯型儿茶素对渥堆过程中六堡茶的滋味具显著贡献(TAV> 1),其中酯型儿茶素与没食子酸是六堡茶渥堆过程滋味品质形成的重要化合物,氨基酸组分对六堡茶滋味无显著贡献。 展开更多
关键词 六堡茶 渥堆 电子舌 滋味成分 相关性 滋味活度值
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不同虫茶及其植物原料的抗氧化作用效果比较 被引量:1
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作者 袁冬寅 张芬 +6 位作者 陈家献 欧淑琼 彭靖茹 张栩浩 黄寿辉 温立香 林玲 《食品安全质量检测学报》 CAS 2024年第3期310-319,共10页
目的比较研究酸枣叶虫茶、茶叶虫茶及其植物原料的体外抗氧化能力。方法采用高效液相色谱法及分光光度法等方法检测酸枣叶、茶叶、酸枣叶虫茶及茶叶虫茶中多酚、总黄酮、咖啡碱、游离氨基酸及可溶性糖含量,并以自由基的清除能力及铁离... 目的比较研究酸枣叶虫茶、茶叶虫茶及其植物原料的体外抗氧化能力。方法采用高效液相色谱法及分光光度法等方法检测酸枣叶、茶叶、酸枣叶虫茶及茶叶虫茶中多酚、总黄酮、咖啡碱、游离氨基酸及可溶性糖含量,并以自由基的清除能力及铁离子还原力作为抗氧化能力的评价指标。结果茶叶中多酚含量最高,显著高于酸枣叶及两种虫茶(P<0.05);酸枣叶中总黄酮、咖啡碱及可溶性糖的含量最高,均显著高于茶叶及两种虫茶(P<0.05),且酸枣叶虫茶不含咖啡碱;茶叶虫茶的游离氨基酸含量最高,显著高于酸枣叶虫茶及植物原料(P<0.05);在抗氧化能力测定中,茶叶对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、羟自由基(·OH)、超氧阴离子自由基(superoxide anion radicals,·O_(2)^(-))、2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)ammonium salt,ABTS]阳离子自由基的清除能力及铁还原能力最高,均显著高于酸枣叶及两种虫茶(P<0.05),而茶叶虫茶的抗氧化活性最弱。Spearman相关性分析表明,4个样品的DPPH自由基、·OH、·O_(2)^(-)、ABTS阳离子自由基清除能力、铁还原力及抗氧化效能综合指数均与多酚、可溶性糖、游离氨基酸含量的相关系数较高,其与多酚、可溶性糖含量分别呈极显著、显著正相关(P<0.01,P<0.05),与游离氨基酸含量均呈显著负相关(P<0.05)。结论植物原料的抗氧化活性强于虫茶,且酸枣叶虫茶强于茶叶虫茶,多酚、可溶性糖是决定两种虫茶及其植物原料抗氧化活性的重要物质。 展开更多
关键词 虫茶 植物原料 活性物质 抗氧化活性 相关性
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产气糟辣椒的微生物与挥发性风味物质研究及相关性分析 被引量:3
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作者 付为艺 苏伟 +2 位作者 母应春 陈添艳 尹学东 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期143-151,I0001,I0002,共11页
为探究夏季引起糟辣椒产气胀罐的潜在微生物及其对挥发性风味的影响,对正常、微产气、产气胀罐的3种样品进行研究,并将微产气样品置于30℃贮存,加速发酵产气,跟踪指标变化。高通量测序结果表明,产气样品的优势细菌门为厚壁菌门,优势细... 为探究夏季引起糟辣椒产气胀罐的潜在微生物及其对挥发性风味的影响,对正常、微产气、产气胀罐的3种样品进行研究,并将微产气样品置于30℃贮存,加速发酵产气,跟踪指标变化。高通量测序结果表明,产气样品的优势细菌门为厚壁菌门,优势细菌属为乳酸杆菌属,是潜在的产气菌株;优势真菌门为子囊菌门,优势真菌属为刺盘孢属。顶空固相微萃取气相色谱-质谱联用共检测到39种挥发性化合物,其中正常样品25种,产气样品29种,酸类物质种类增加,醇类和酯类物质种类减少。通过主成分分析和正交偏最小二乘判别分析得到产气前后挥发性风味物质差异显著,并利用投影变量重要性因子筛选出14种重要风味物质。基于Pearson相关系数,发现乳酸杆菌属与其他细菌属存在负相关关系,细菌属与酯类物质存在正相关关系,真菌属与醇类物质存在负相关关系。此结果可为糟辣椒的安全质量控制研究奠定基础。 展开更多
关键词 产气糟辣椒 高通量测序 微生物多样性 挥发性风味物质 相关性分析
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基于专利数据库对脉痹处方规律及核心中药的数据挖掘研究 被引量:1
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作者 杨振宇 李纪新 +3 位作者 李丙泉 顾晨浩 李晨 郭丹丹 《中国医药导报》 CAS 2024年第6期21-25,33,共6页
目的 基于国家专利复方,探寻中医药干预脉痹的遣方用药规律。方法 计算机检索国家专利数据建库至2023年3月有关中医药干预脉痹的专利复方,运用Excel进行数据清洗和频次、性味、归经的统计,SPSS Modeler18.0和R.4.3.1进行中药关联性及层... 目的 基于国家专利复方,探寻中医药干预脉痹的遣方用药规律。方法 计算机检索国家专利数据建库至2023年3月有关中医药干预脉痹的专利复方,运用Excel进行数据清洗和频次、性味、归经的统计,SPSS Modeler18.0和R.4.3.1进行中药关联性及层次聚类分析,Cytoscape 3.9.1对共现网络进行可视化升级。结果 本研究纳入专利复方124项,涉及中药324味;高频中药包括丹参、黄芪等;药性以寒、温为主,药味以苦、甘、辛居多,归经主要归肝经;常见药对包括“黄芪-丹参”等;常用角药组合包含“山楂-丹参-川芎”等;层次聚类得到4组聚类组合。结论 专利复方治疗脉痹以活血祛瘀,化浊降脂,补益气血为主,本研究梳理了治疗脉痹的核心中药,以期为临床遣方用药和未来新药研发提供思路。 展开更多
关键词 脉痹 动脉粥样硬化 复方 专利 数据挖掘 层次聚类 中介中心性 Phi相关系数
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Pichia kudriavzevii生物强化对酱香型白酒酒醅微生物群落结构及挥发性风味组分的影响 被引量:1
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作者 倪冰倩 夏韩硕 +5 位作者 闵伟红 朱华 王昆 李微微 李秀婷 张成楠 《食品科学技术学报》 EI CAS CSCD 北大核心 2024年第2期93-108,130,共17页
乙酸苯乙酯具有玫瑰花香、蜂蜜香、苹果香等风味特征,是酱香型白酒的重要风味物质。高产乙酸苯乙酯酵母菌的筛选及发酵应用对于改善酱香型白酒风味,提高白酒品质具有重要意义。从酱香型白酒酿造过程的酒醅样品中筛选得到1株乙酸苯乙酯... 乙酸苯乙酯具有玫瑰花香、蜂蜜香、苹果香等风味特征,是酱香型白酒的重要风味物质。高产乙酸苯乙酯酵母菌的筛选及发酵应用对于改善酱香型白酒风味,提高白酒品质具有重要意义。从酱香型白酒酿造过程的酒醅样品中筛选得到1株乙酸苯乙酯产量相对较高的菌株Pichia kudriavzevii X-8,将其应用于酱香型白酒模拟发酵实验。结果表明:A组(未添加菌株Pichia kudriavzevii X-8)和B组(添加菌株Pichia kudriavzevii X-8)酒醅样品中挥发性化合物分别有60、65种,其中B组的酯类、醇类、酸类及其他风味物质的种类及含量均高于A组。发酵30 d后,B组乙酸苯乙酯质量比(0.214μg/g)约为A组(0.121μg/g)的2倍。B组特有的优势属为Weissella和Pichia,2组酒醅样品中Lactobacillus和Pediococcus,Saccharomycopsis和Saccharomyces的菌落丰度也存在差异。加入Pichia kudriavzevii X-8后,对酒醅的理化指标影响不大,增强了水质量分数、酸度及风味物质与真菌属微生物的相关性,提高了乙酸苯乙酯及其他重要风味物质的含量。研究结果旨在为酱香型白酒品质提升和功能菌株在酱香型白酒中的实际应用提供理论参考。 展开更多
关键词 酱香型白酒 生物强化 乙酸苯乙酯 挥发性风味物质 微生物群落 相关性分析
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复合地层中盾构施工掘进参数相关性及预测研究 被引量:3
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作者 何华飞 林雪冰 +3 位作者 胡朋 贾柏源 陈逸民 宋克志 《现代城市轨道交通》 2024年第5期88-95,共8页
在盾构掘进过程中,众多掘进参数交织在一起,规律错综复杂。科学地分析这些参数之间的规律与相关性,对于盾构的实时控制至关重要。依托济南地铁R2左线工程,基于机器学习方法对复合地层中盾构施工的掘进参数进行研究。首先,分析地层参数... 在盾构掘进过程中,众多掘进参数交织在一起,规律错综复杂。科学地分析这些参数之间的规律与相关性,对于盾构的实时控制至关重要。依托济南地铁R2左线工程,基于机器学习方法对复合地层中盾构施工的掘进参数进行研究。首先,分析地层参数与盾构掘进参数之间的关系,通过相关性分析发现,6个掘进参数中,盾构的总推进力和刀盘扭矩与其他参数的相关性尤为显著。然后,利用支持向量机算法,对不同地层中盾构总推进力和刀盘扭矩进行预测。预测结果与实际监测结果基本一致,证明这种方法的有效性。最后,为进一步提高预测精度,采用PSO算法对盾构掘进参数预测模型进行优化。优化后的模型总推进力R2提升约3%,刀盘扭矩R2提升约10%,优化效果十分显著。该项研究可为复合地层中盾构施工参数选择提供重要参考。 展开更多
关键词 盾构施工 复合地层 机器学习 掘进参数 相关性分析 支持向量机
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四川烤烟Amadori化合物特征及其与感官品质关联分析
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作者 李晓阳 靳冬梅 +4 位作者 庞夙 庞雪莉 邱军 魏玉西 曹建敏 《云南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期84-92,共9页
【目的】探究烤烟中Amadori化合物与烟叶品质的关系。【方法】以四川初烤烟叶为材料,采用统计学方法研究四川不同香型烤烟中Amadori化合物的含量特征及其与烟叶感官品质的关系。【结果】(1)四川烤烟Amadori化合物中1-脱氧-1-L-脯氨酸-D... 【目的】探究烤烟中Amadori化合物与烟叶品质的关系。【方法】以四川初烤烟叶为材料,采用统计学方法研究四川不同香型烤烟中Amadori化合物的含量特征及其与烟叶感官品质的关系。【结果】(1)四川烤烟Amadori化合物中1-脱氧-1-L-脯氨酸-D-果糖(Fru-Pro)含量最高,其次为1-脱氧-1-L-丙氨酸-D-果糖(Fru-Ala);大多数Amadori化合物的含量在清甜香型烤烟与蜜甜香型烤烟、醇甜香型烤烟间差异显著,但在后两者间的差异不大;清甜香型烤烟的Amadori化合物总量、Fru-Pro含量和1-脱氧-1-L-谷氨酸-D-果糖(Fru-Glu)含量极显著高于蜜甜香型和醇甜香型烤烟,葡萄糖胺、Fru-Ala、1-脱氧-1-L-缬氨酸-D-果糖(Fru-Val)、1-脱氧-1-L-亮氨酸-D-果糖+1-脱氧-1-L-异亮氨酸-D-果糖(Fru-Leu+Ile)和1-脱氧-1-L-苯丙氨酸-D-果糖(Fru-Phe)的含量显著或极显著低于蜜甜香型和醇甜香型烤烟。(2)大多数Amadori化合物的含量与前体氨基酸含量呈显著或极显著正相关,其中葡萄糖胺、Fru-Glu、1-脱氧-1-L-甘氨酸-D-果糖(Fru-Gly)和l-脱氧-1-L-色氨酸-D-果糖(Fru-Trp)的含量与全部8种前体氨基酸含量呈极显著正相关性。(3)大部分Amadori化合物与感官品质指标呈负相关,仅Fru-Pro与香气量呈极显著正相关;而Amadori化合物转化率与感官品质指标间以正相关为主。(4)Mantel检验表明:Amadori化合物与其转化率间的关联性较强,且大多为正相关;Amadori化合物及其转化率主要影响烤烟的香气特性,葡萄糖胺对烤烟感官品质影响最大,含量过高对烟叶品质不利。【结论】Amadori化合物与烤烟感官品质关系密切,且大部分Amadori化合物对感官品质有负面影响。总体来看,Amadori化合物对烤烟香气特性影响最大,其次为口感特性,对烟气特性影响最小。 展开更多
关键词 烤烟 AMADORI化合物 感官品质 相关性
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鄂尔多斯盆地甘泉-富县地区延长组长9-长7段烃源岩地球化学特征及长8致密油源对比
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作者 蒋杨 弓虎军 蒲仁海 《沉积与特提斯地质》 CAS CSCD 北大核心 2024年第3期656-670,共15页
为评价鄂尔多斯盆地甘泉—富县地区长9—长7段烃源岩品质,探讨长8致密油油气来源问题,通过TOC、氯仿沥青“A”、岩石热解参数、镜质体反射率、有机质显微组分、生物标记化合物、单体碳同位素等技术方法,研究该区长9—长7段烃源岩生烃潜... 为评价鄂尔多斯盆地甘泉—富县地区长9—长7段烃源岩品质,探讨长8致密油油气来源问题,通过TOC、氯仿沥青“A”、岩石热解参数、镜质体反射率、有机质显微组分、生物标记化合物、单体碳同位素等技术方法,研究该区长9—长7段烃源岩生烃潜力、母质来源及沉积环境,并对长8段原油样品进行地球化学分析及油源对比。结果表明:(1)研究区主要发育长9、长8、长7三套暗色泥岩,长9—长7段暗色泥岩有机质类型为Ⅱ1~Ⅱ2型;其TOC含量为3.25%~7.92%,生烃潜量为3.06~38.13 mg/g,氯仿沥青“A”含量为0.18%~0.69%,为最好烃源岩,且均处于高成熟演化阶段。(2)长9—长7段暗色泥岩样品形成于典型的淡水湖泊环境,长9沉积期为氧化—亚氧化沉积环境,长8沉积期为弱还原沉积环境,长7沉积期为强还原沉积环境,长9—长7段烃源岩母质来源为低等水生生物和陆源高等植物混源。(3)研究区长81与长82原油为同一类原油,长9—长7段烃源岩对长8致密油均有贡献,其中以长7烃源岩为主。 展开更多
关键词 鄂尔多斯盆地 烃源岩评价 生物标志化合物 油源对比
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VMD引导的轮对与轴承复合故障诊断方法
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作者 易彩 林建辉 +3 位作者 汪浩 廖小康 吴文逸 冉乐 《西南交通大学学报》 EI CSCD 北大核心 2024年第1期151-159,共9页
针对列车轮对轴承系统复合故障难以辨识与诊断问题,提出一种变分模态分解(variational mode decomposition,VMD)引导的多故障特征提取匹配方法.首先,为避免预定义模式数在运行过程中对先验知识依赖从而对诊断结果造成影响,对原始轴箱振... 针对列车轮对轴承系统复合故障难以辨识与诊断问题,提出一种变分模态分解(variational mode decomposition,VMD)引导的多故障特征提取匹配方法.首先,为避免预定义模式数在运行过程中对先验知识依赖从而对诊断结果造成影响,对原始轴箱振动数据进行逐阶VMD分解,模式数为2~N;其次,对VMD分解获取的本征模态函数(VMD intrinsic mode functions,VIMF)进行相关峭度计算,提取相关峭度最大的VIMF;然后,将相关峭度最大的VIMF进行平方包络分析,提取故障特征频率;最后,将所提方法与快速峭度谱、相关峭度谱方法进行对比.仿真信号和试验数据分析表明:所提方法完全规避了VMD模型中关键参数K的选择问题,可以准确、有效地分别提取出轮对和轴承的故障特征;与快速谱峭度与相关谱峭度方法相比,获取的故障特征谐波分量在数量和信噪比上均具有明显优势. 展开更多
关键词 变分模态分解 复合故障诊断 轮对轴承 相关峭度 平方包络
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不同产区雪茄烟叶Amadori化合物含量与品质的关系分析
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作者 施友志 申民翀 +7 位作者 王剑 潘勇 杜甫 赵泽玉 李子玮 王琰琰 贾志忠 袁晓龙 《特产研究》 2024年第4期20-24,共5页
为探究不同产区雪茄烟叶中Amadori化合物含量差异,选取5个产区的68个雪茄烟叶,采用高效液相色谱质谱方法测定不同产区雪茄烟叶Amadori化合物含量及其相关性,以及与化学品质指标之间相关性。结果表明,不同产区雪茄烟Amadori化合物总量整... 为探究不同产区雪茄烟叶中Amadori化合物含量差异,选取5个产区的68个雪茄烟叶,采用高效液相色谱质谱方法测定不同产区雪茄烟叶Amadori化合物含量及其相关性,以及与化学品质指标之间相关性。结果表明,不同产区雪茄烟Amadori化合物总量整体表现为上部叶>中部叶>下部叶,各含量数据基本服从正态分布,其中Fru-Ala含量最高。各Amadori化合物间大多呈现正相关性。不同产区雪茄Amadori化合物含量整体表现为四川>云南>湖北>海南>多米尼加。Fru-Asn、Fru-Gly、Fru-Leu、Fru-Phe、Fru-Pro、Fru-Val与总糖、还原糖、烟碱、糖碱比极显著正相关性。Fru-Phe、Fru-Tyr、Fru-Ile和Fru-Ala只与钾氯比呈显著负相关。本研究可为不同产区雪茄烟叶的内含物差异及转化相关研究提供理论支撑。 展开更多
关键词 雪茄烟叶 AMADORI化合物 产区 相关性
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