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基于HS-SPME-GC-MS分析凤香型白酒中风味物质条件优化

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酿酒 2024年第4期51卷 92-98页

作者：凤旭凯张亚芳董飘然张永利金成勇陕西西凤酒股份有限公司陕西宝鸡721406

该文使用气相色谱质谱联用仪(gas chromatography-mass spectrometry,GC-MS)对凤香型白酒中风味物质成分进行分析,在进样前对萃取的样品量、萃取时间、萃取温度、平衡时间、解析时间6个条件进行优化,以期得到更全面的风味物质的组成。... 详细信息

该文使用气相色谱质谱联用仪(gas chromatography-mass spectrometry,GC-MS)对凤香型白酒中风味物质成分进行分析,在进样前对萃取的样品量、萃取时间、萃取温度、平衡时间、解析时间6个条件进行优化,以期得到更全面的风味物质的组成。实验结果表明:对10 m L样品中加入0.3 g/L氯化钠,在50℃条件下萃取30 min,解析2 min,能够得到较好的GC-MS分析结果,共定性出81种风味物质,包括酯类、醇类、酸类、芳香化合物等。该项研究为进一步筛选出凤香型白酒特征香气物质提供技术支持。

关键词：凤香型白酒顶空固相微萃取风味物质

Ozone generation enhanced by silica catalyst in packed-bed DBD reactor

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Plasma Science and Technology 2021年第8期23卷 89-94页

作者： Xin ZENG yafang zhang Liangyin GUO Wenquan GU Ping YUAN Linsheng WEI School of Resources Environmental&Chemical Engineering Nanchang UniversityNanchang 330031People's Republic of China

In this paper,three dielectric barrier discharge(DBD)configurations,which were plain DBD with no packing,DBD with packed pure quartz fibers and DBD with packed loaded quartz fibers,were employed to investigate the effect and catalytic mechanism of catalyst materials in a packed-bed ozone *** the experimental results,it was clear that the DBD configuration with packed pure fibers and packed loaded fibers promotes ozone *** the packed-bed reactor,ozone concentration and ozone yield were enhanced by an increase of electric field in the discharge gap with the packed-bed ***,the enhancement of ozone concentration and yield for the DBD reactor packed by loaded fibers with silica nanoparticles was due to the catalysis of silica nanoparticles on the fiber *** adsorption of silica nanoparticles on the fiber surface can prolong the retention time of active species and enhance surface reactions.

关键词： DBD ozone generation packed-bed reactor silica catalysis surface reaction

基于GC-O-MS和OAV法鉴定西凤酒中关键香气成分

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酿酒 2024年第5期51卷 69-73页

作者：张亚芳凤旭凯董飘然张永利金成勇陕西西凤酒股份有限公司陕西宝鸡721406

采用顶空-固相微萃取(Headspace Solid-Phase Microextraction,HS-SPME)和气相色谱-嗅闻-质谱联用(Gas Chromatography-Olfactory-Mass Spectrometry,GC-O-MS)技术结合香气活度值(Odor Activity Value,OAV)分析鉴定西凤酒中关键香气成分。结果显示,鉴定出89种挥发性化合物,主要包含酯类60种,占相对总含量95.17%;其他还包括醇类12种、醛酮类9种等。经GC-O直接嗅辨分析共确定了5大类香气印象,分别为果香、酒香、木香、焦香和蜜香。综合OAV和GC-O-MS分析,最终确认丁酸乙酯、庚酸乙酯、己醛、戊酸乙酯、丁酸异戊酯、己酸乙酯、月桂酸乙酯可以表现出“果香”特征,且丁酸乙酯、己醛、庚酸乙酯、戊酸乙酯、辛酸乙酯对“果香”具有较大的贡献(245.0

关键词：西凤酒 GC-O-MS OAV 香气物质

pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages for enhanced MDR reversal and chemotherapy

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Asian Journal of Pharmaceutical Sciences 2021年第3期16卷 363-373页

作者： Yong Xu Shi Wang Longshun Yang Yuhang Dong yafang zhang Guoqing Yan Rupei Tang Engineering Research Center for Biomedical Materials Anhui Key Laboratory of Modern BiomanufacturingSchool of Life SciencesAnhui UniversityHefei 230601China

TPGS approved by FDA can be used as a P-gp inhibitor to effectively reverse multi-drug resistance(MDR)and as an anticancer agent for synergistic antitumor ***,the comparatively high critical micelle concentration(CMC),low drug loading(DL)and poor tumor target limit its further clinical *** overcome these drawbacks,the pH-sensitive star-shaped TPGS copolymers were successfully constructed via using pentaerythritol as the initial materials,ortho esters as the pH-triggered linkages and TPGS active-ester as the terminated MDR *** amphiphilic star-shaped TPGS copolymers could self-assemble into free and doxorubicin(DOX)-loaded micelles at neutral aqueous *** micelles exhibited the lower CMC(8.2×10^(−5) mg/ml),higher DL(10.8%)and long-term storage and circulation stability,and showed enhanced cellular uptake,apoptosis,cytotoxicity,and growth inhibition for in vitro MCF-7/ADR and/or MCF-7/ADR multicellular spheroids and in vivo MCF-7/ADR tumors via efficiently targeted drug release at tumoral intracellular pH(5.0),MDR reversal of TPGS,and synergistic effect of DOX and ***,the pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages are potentially useful to clinically transform for enhanced MDR cancer treatment.

关键词： TPGS Ortho esters Star-shaped copolymers MDR reversal

Influence of Intersection Angle of Prefabricated Cracks on Impact Failure of Flattened Brazilian Disc

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Journal of Wuhan University of Technology(Materials Science) 2021年第6期36卷 884-890页

作者： LIU Hao zhang yafang YIN Guoqi OU Chenggui LU Juan HUO Yongjie Shenzhen Municipal Design Research Institute Co.Ltd Shenzhen 518029China School of Civil Engineering Guangzhou UniversityGuangzhou 510006China

Both experimental and numerical approaches were used to study dynamic failure properties and patterns of flattened Brazilian discs,containing two prefabricated cracks intersected at a varying *** of crack initiation,propagation,and cut-through were scrutinized and influences of the intersection angle on specimen strength and acoustic emission performance were also *** primary cracks initialize near the middle or the tip points of the upper prefabricated crack,and they continue to develop along the load direction and finally cut through the *** secondary cracks could be observed in directions almost horizontal or parallel to the directions of prefabricated ***,it is found that stress intensity factor reaches its maximum for specimen with intersection angle of 0 degree.

关键词： crack flattened brazilian disc impact load SHPB failure process acoustic emission

Impact Failure of Flattened Brazilian Disc with Cracks——Process and Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2020年第5期35卷 1003-1010页

作者： zhang yafang LIU Hao YIN Guoqi OU Chenggui LU Juan HE Juan School o f Civil Engineering Guangzhou UniversityGuangzhou 510006China Shenzhen Municipal Design Research Institute Co.Ltd. Shenzhen 518029China

Split Hopkinson pressure bar(SHPB)has been used to study the dynamic failure pattern of flattened mortar Brazilian disc under impact *** disc contains several prefabricated cracks paralleled to each *** FEM has also been adopted to simulate such failure *** mechanism of crack initiation,propagation and cut-through have been scrutinized with both experimental and numerical *** of the number of the prefabricated cracks on the specimen strength and acoustic emission(AE)performance can be observed and *** results show that the strength decreases and AE counts increases,when the number of the prefabricated cracks increases.

关键词： paralleled cracks flattened brazilian disc impact load SHPB failure process acoustic emission

云南省不同民族中老年人群健康状况及影响因素研究

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中国农村卫生事业管理 2024年第3期44卷 214-221页

作者：李小菊张亚访李戎陈杰严朝芳黄源邓睿昆明医科大学公共卫生学院云南昆明650500

目的从身体、心理和社会维度,了解云南省不同民族中老年人健康现状并探索其影响因素,为维护促进中老年人健康提供参考。方法采用多阶段随机整群抽样,在云南省6个县(市)抽取2750名中老年人进行问卷调查。结果云南省中老年人中日常生活活... 详细信息

目的从身体、心理和社会维度,了解云南省不同民族中老年人健康现状并探索其影响因素,为维护促进中老年人健康提供参考。方法采用多阶段随机整群抽样,在云南省6个县(市)抽取2750名中老年人进行问卷调查。结果云南省中老年人中日常生活活动失能率、抑郁检出率和中低社会支持率分别为40.55%、20.22%和60.81%。Logistic回归分析结果显示,影响中老年人生理健康状况的主要因素有民族、性别、年龄、受教育程度、婚姻状况和亲属照顾;影响中老年人心理健康的主要因素有民族、性别、慢性病患病情况;影响中老年人社会健康的主要因素有居住地、年龄、婚姻状况、孩子数量及亲属照顾。上述差异均有统计学意义(P<0.05)。结论云南省中老年人的整体健康状况并不理想,性别和民族身份是影响生理和心理健康的重要因素,未来宜继续落实基本公共卫生服务,加大对少数民族女性健康的关注,采取针对性的服务或干预措施。

关键词：中老年人健康状况日常生活活动能力抑郁社会支持

Isolation and characterization of rl_(t), a gene that controls leaf rolling in rice

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Chinese Science Bulletin 2014年第25期59卷 3142-3152页

作者： Lei Li Xiang Xue Zongxiang Chen yafang zhang Yuyin Ma Cunhong Pan Junkai Zhu Xuebiao Pan Shimin Zuo Key Laboratory of Crop Genetics and Physiology of Jiangsu Province College of Agriculture Yangzhou University/Key Laboratory of Plant Functional Genomics of the Ministry of Education Department of Biochemical Engineering Yangzhou Polytechnic College Lixiahe Agricultural Research Institute of Jiangsu Province

Moderate leaf rolling is one of the most important morphological traits in rice breeding for plant *** studies have shown that the rl(t)gene has a high breeding potential for developing hybrid-rice varieties with an ideal ideotype,because it leads to an appropriate leaf rolling index(LRI)of about 30%in the heterozygous state,and had a positive effect on grain *** this study,we isolated rl(t)and performed a preliminary investigation of its function in regulating leaf rolling in *** sequencing identified a single base change(G to T)in the finely mapped region(11 kb)containing rl(t),and this is located in 30-untranslated region(30-UTR)of the only predicted gene,Roc5(Rice outermost cell-specific).The expression level of Roc5 is significantly higher in the rl(t)mutant than in the *** RNAi and overexpression analysis,we found that the expression level of Roc5 correlated with LRI and leaf bulliform area,and wasalso associated with leaf abaxial or adaxial *** results confirmed that Roc5 controls leaf rolling in a dosage-dependent *** analysis revealed a conserved 17-nt sequence(called the GU-rich element)in the 30-UTR of HD-GL2(Homeodomain-Glabra2)family genes including *** on the model of this element in regulating mRNA stability in mammals,we speculate that the single nucleotide change in this element accounts for the higher expression level of Roc5 in the rl(t)mutant compared to the wild-type,which ultimately leads to adaxial rolling of the *** discovery further enhances our knowledge of the molecular mechanisms underlying leaf rolling in rice.

关键词：水稻育种基因家族 RL 卷叶分离控制特性理想株型

Analyze the Performance of Electroactive Anticorrosion Coating of Medical Magnesium Alloy Using Deep Learning

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Computers, Materials & Continua 2024年第4期79卷 263-278页

作者： Yashan Feng yafang Tian Yongxin Yang Yufang zhang Haiwei Guo Jing’an Li Advanced Functional Materials Laboratory Zhengzhou Railway Vocational and Technical CollegeZhengzhou450000China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450000China

Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.

关键词： Medical magnesium alloys hydrogen gas anticorrosion total acidity potential of the hydrogen(pH)