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月月粉TGAs基因结构及RcTGA2抗灰葡萄孢菌功能分析 被引量:1
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作者 高鹏华 张颢 +4 位作者 晏慧君 陈宇春 范元兰 鄢波 邱显钦 《植物遗传资源学报》 CAS CSCD 北大核心 2021年第4期1157-1166,共10页
TGA(TGACG motif-binding factor)转录因子是bZIP转录因子家族中重要的一组,对植物病原菌侵染具有广谱抗性。本研究鉴定了月月粉月季(Rosa chinensis Jacq.Old Blush)TGA家族成员,并对其理化性质、亚细胞定位、进化特征和表达模式进行... TGA(TGACG motif-binding factor)转录因子是bZIP转录因子家族中重要的一组,对植物病原菌侵染具有广谱抗性。本研究鉴定了月月粉月季(Rosa chinensis Jacq.Old Blush)TGA家族成员,并对其理化性质、亚细胞定位、进化特征和表达模式进行分析。鉴定获得7个RcTGAs,均包含bZIP1(cl21462)和DOG1(pfam14144)的保守结构域,氨基酸大小为324-545aa,分子量在36.68-60.17KD之间,等电点在5.52-8.96之间,二级结构主要为α-螺旋,均为亲水性蛋白,主要位于细胞核内。进化分析将来自月月粉月季、拟南芥(Arabidopsis thaliana(L.)Heynh.)、野草莓(Fragaria vesca L.)、水蜜桃(Prunus persica(L.)Batsch)、苹果(Malus domestica(Suckow)Borkh.)的TGAs分为6个亚组。qPCR实验表明,灰葡萄孢菌侵染月季花瓣RcTGA4表达量无显著变化,RcTGA6随侵染时间的延长表达量呈下降趋势。RcTGA1/2表达呈显著上升的趋势,RcTGA5/7呈现先上升后下降的趋势,表明RcTGA1/2/3/5/7可能在月季-灰霉菌互作过程中发挥了重要作用,这5个基因可作为进一步抗病研究和功能分析的候选基因。通过VIGS沉默RcTGA2基因,灰葡萄孢菌侵染48 h后,月季花瓣病斑直径显著增大,表明RcTGA2与月季对灰葡萄孢菌的抗性有关。 展开更多
关键词 tgas 月季灰霉病 灰葡萄孢菌 生物信息学分析 实时荧光定量PCR VIGS
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热重分析/红外光谱-气相色谱-质谱联用技术测定松针中6种常见微塑料
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作者 韩卓 刘禹慧 +2 位作者 魏晓菲 李彭辉 宋善军 《分析测试学报》 CAS CSCD 北大核心 2024年第8期1249-1256,共8页
该研究基于热重分析/红外光谱-气相色谱-质谱(TGA/FTIR-GC-MS)联用技术建立了可用于聚乙烯(PE)、聚丙烯(PP)、聚苯乙烯(PS)、聚氯乙烯(PVC)、聚对苯二甲酸乙二酯(PET)、聚碳酸酯(PC)6种常见微塑料的定性定量检测方法。方法检出限为0.03~... 该研究基于热重分析/红外光谱-气相色谱-质谱(TGA/FTIR-GC-MS)联用技术建立了可用于聚乙烯(PE)、聚丙烯(PP)、聚苯乙烯(PS)、聚氯乙烯(PVC)、聚对苯二甲酸乙二酯(PET)、聚碳酸酯(PC)6种常见微塑料的定性定量检测方法。方法检出限为0.03~1.11μg,相对标准偏差为4.0%~12%(n=3),加标回收率为80.4%~93.3%。应用所建立的方法对来自武夷山、青海湖、大兴安岭等12个采样点的松针样品进行分析,得到6种微塑料的浓度范围为0.01~3.15μg·mg^(-1)。此外,样品中6种塑料均有检出,检出率依次为PE、PP和PS(100%)、PET(92%)、PC(60%)、PVC(8%)。该方法可为我国微塑料环境污染评估及环境行为研究提供技术支持。 展开更多
关键词 热重分析/红外光谱-气相色谱-质谱(TGA/FTIR-GC-MS)联用技术 微塑料 松针 定量分析
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A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications
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作者 Wadah Mohammed Zeinab Osman +1 位作者 Salah Elarabi Bertrand Charrier 《Journal of Renewable Materials》 EI CAS 2024年第4期721-736,共16页
The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable app... The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing. 展开更多
关键词 BAGASSE kenaf bast fibers cotton stalks TGA DSC FTIR
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高氯酸盐对Al/PTFE活性材料热反应行为的影响
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作者 周丹 李如江 +1 位作者 周鹏 王梦飞 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第7期150-157,共8页
为了研究高氯酸盐对Al/PTFE二元活性材料热反应行为的影响,选用高氯酸钾(KClO_(4))和高氯酸钠(NaClO_(4))作为填充材料,采用湿混法分别制备了KClO_(4)/Al/PTFE和NaClO_(4)/Al/PTFE三元活性材料样品。利用扫描电子显微镜(SEM)观察了样品... 为了研究高氯酸盐对Al/PTFE二元活性材料热反应行为的影响,选用高氯酸钾(KClO_(4))和高氯酸钠(NaClO_(4))作为填充材料,采用湿混法分别制备了KClO_(4)/Al/PTFE和NaClO_(4)/Al/PTFE三元活性材料样品。利用扫描电子显微镜(SEM)观察了样品的微观形貌;采用同步热分析技术(TGA-DSC)、 X射线衍射技术(XRD)以及自建的燃烧测试装置,对高氯酸盐/Al/PTFE三元活性材料体系的热性能和燃烧性能进行了研究。结果显示:高氯酸盐粉末和Al粉均匀分布在PTFE基底上。通过TG-DSC同步热分析实验发现高氯酸盐/Al/PTFE活性材料体系分解反应的开始温度均低于Al/PTFE活性材料。其中,KClO_(4)/Al/PTFE三元活性材料的分解放热量略低于NaClO_(4)/Al/PTFE三元活性材料;KClO_(4)的分解温度在PTFE的催化作用下降低,且KClO_(4)/Al/PTFE三元活性材料的放热峰值温度也降低了29.1℃;而NaClO_(4)/Al/PTFE三元活性材料的放热峰值温度提高了7.5℃。相比NaClO_(4),KClO_(4)的加入有助于C的利用。在点火实验中,高氯酸盐的引入可有效增加Al/PTFE活性材料体系的燃烧持续时间、爆燃持续时间,并提高了最高压力,但也降低了体系的升压速率、增加了达到最大压力的时间。 展开更多
关键词 高氯酸盐/Al/PTFE 活性材料 TGA:DSC XRD 燃烧
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Surface Morphology and Thermo-Electrical Energy Analysis of Polyaniline (PANI) Incorporated Cotton Fabric
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作者 Md.Shohan Parvez Md.Mustafizur Rahman +1 位作者 Mahendran Samykano Mohammad Yeakub Ali 《Energy Engineering》 EI 2024年第1期1-12,共12页
With the exponential development in wearable electronics,a significant paradigm shift is observed from rigid electronics to flexible wearable devices.Polyaniline(PANI)is considered as a dominant material in this secto... With the exponential development in wearable electronics,a significant paradigm shift is observed from rigid electronics to flexible wearable devices.Polyaniline(PANI)is considered as a dominant material in this sector,as it is endowed with the optical properties of both metal and semiconductors.However,its widespread application got delineated because of its irregular rigid form,level of conductivity,and precise choice of solvents.Incorporating PANI in textile materials can generate promising functionality for wearable applications.This research work employed a straightforward in-situ chemical oxidative polymerization to synthesize PANI on Cotton fabric surfaces with varying dopant(HCl)concentrations.Pre-treatment using NaOH is implemented to improve the conductivity of the fabric surface by increasing the monomer absorption.This research explores the morphological and structural analysis employing SEM,FTIR and EDX.The surface resistivity was measured using a digital multimeter,and thermal stability is measured using TGA.Upon successful polymerization,a homogenous coating layer is observed.It is revealed that the simple pre-treatment technique significantly reduces the surface resistivity of Cotton fabric to 1.27 kΩ/cm with increasing acid concentration and thermal stability.The electro-thermal energy can also reach up to 38.2°C within 50 s with a deployed voltage of 15 V.The modified fabric is anticipated to be used in thermal regulation,supercapacitor,sensor,UV shielding,antimicrobial and other prospective functional applications. 展开更多
关键词 POLYANILINE cotton in-situ polymerization SEM TGA heating fabric
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热分析技术在弹性体材料中的应用
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作者 焦冰晶 肖恒 +2 位作者 吕小王 曹红宝 田雨 《弹性体》 CAS 2024年第3期70-80,共11页
热分析技术是评价弹性体材料热行为的主要手段之一。通过热分析技术全面深入地研究弹性体的物化特性,对改善和提高弹性体的应用性能具有重要的现实意义和价值。本文介绍了常见的热分析方法,包括:差示扫描量热法(DSC)、热机械分析法(TMA... 热分析技术是评价弹性体材料热行为的主要手段之一。通过热分析技术全面深入地研究弹性体的物化特性,对改善和提高弹性体的应用性能具有重要的现实意义和价值。本文介绍了常见的热分析方法,包括:差示扫描量热法(DSC)、热机械分析法(TMA)、动态热机械分析(DMA)、热重分析(TGA)技术及热分析联用技术在弹性体材料中的应用研究进展。综述了热分析技术表征弹性体材料的特点及优势,同时展望了热分析技术的应用前景。 展开更多
关键词 弹性体 热分析 差示扫描量热法(DSC) 热机械分析法(TMA) 动态热机械分析(DMA) 热重分析技术(TGA) 热分析联用技术
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澳大利亚更新法瑞西单抗产品信息警示视网膜血管炎的风险
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《中国处方药》 2024年第6期I0001-I0001,共1页
澳大利亚药品管理局(TGA)调查了接受法瑞西单抗(商品名:罗视佳)治疗的患者发生视网膜血管炎和/或视网膜闭塞性血管炎的风险,认为需要在该药品的产品信息(PI)和消费者药品信息(CMI)中进一步强化对上述风险的警示。澳大利亚TGA已更新法瑞... 澳大利亚药品管理局(TGA)调查了接受法瑞西单抗(商品名:罗视佳)治疗的患者发生视网膜血管炎和/或视网膜闭塞性血管炎的风险,认为需要在该药品的产品信息(PI)和消费者药品信息(CMI)中进一步强化对上述风险的警示。澳大利亚TGA已更新法瑞西单抗的产品信息(第4.4节和第4.8节)以提示新增安全信息,并向开具玻璃体内注射处方的眼科医生发布致医务人员函。此外,还对消费者药品信息进行更新以反映上述修订。 展开更多
关键词 药品信息 视网膜血管炎 玻璃体内注射 眼科医生 医务人员 澳大利亚 TGA 警示
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不同浓度四甲基戊二酸拌种对玉米苗期生长的影响
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作者 任士伟 贾莉莉 +3 位作者 王龙 刘村平 朱晓洁 孟鑫 《农业工程技术》 2024年第7期20-22,共3页
为探究不同浓度四甲基戊二酸(TGA)拌种对玉米幼苗生长、物质积累和根茎物质分配的影响,试验设计0~100 mg/L多个梯度浓度拌种,然后测量低温情况下玉米幼苗的生长发育情况。试验结果表明,TGA拌种浓度在6.25~50.00 mg/L时能够促进玉米苗期... 为探究不同浓度四甲基戊二酸(TGA)拌种对玉米幼苗生长、物质积累和根茎物质分配的影响,试验设计0~100 mg/L多个梯度浓度拌种,然后测量低温情况下玉米幼苗的生长发育情况。试验结果表明,TGA拌种浓度在6.25~50.00 mg/L时能够促进玉米苗期生长,同时物质积累和营养物质向根系转移。其中,TGA浓度为12.5 mg/L时表现效果为佳。但该次试验浓度设计非等差浓度设计,仍存在局限性,后期有必要缩小浓度梯度进行再次试验。 展开更多
关键词 TGA 玉米 拌种 苗期 出苗率 物质积累 物质分配
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高校化学TGA、SEM和XRD的微视频教学探索
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作者 姚平平 卢怡 +8 位作者 杨宇翔 张敏 田振芬 杨昊宇 龙应钊 徐志珍 孙学芹 刘金库 王海文 《广州化工》 CAS 2023年第15期177-179,共3页
高校化学专业实验为研究性教学的重要环节,既承担知识和技能的传授,同时启迪学生的创造性思维并提升其素质。后疫情时期,开展大学化学专业实验混合式教学模式势在必行。作为一种多功能、性能优良的无机化学材料,纳米氧化锌被科学家们持... 高校化学专业实验为研究性教学的重要环节,既承担知识和技能的传授,同时启迪学生的创造性思维并提升其素质。后疫情时期,开展大学化学专业实验混合式教学模式势在必行。作为一种多功能、性能优良的无机化学材料,纳米氧化锌被科学家们持续关注。以掺铝氧化锌(ZAO)为例介绍表征其结构、形貌和热失重的三种大型仪器的操作短视频制作:热失重分析仪(TGA)、飞纳扫描电子显微镜(SEM)和X射线粉末衍射仪(XRD)。期待为新冠肺炎疫情常态化防控背景下,高校化学专业实验、创新实验和科普平台的建立提供素材及方法借鉴。 展开更多
关键词 微视频制作 ZAO TGA SEM XRD
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A Study on the Effect of Low Calcium Ultra-fine Fly Ash as a Partial Sustainable Supplementary Material to Cement in Self-compacting Concrete 被引量:2
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作者 Adapala Sunny Suprakash Karthiyaini S 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期330-341,共12页
The aim and scope of the present study were to determine the efficacy of UFFA in evaluating the workability,static and dynamic stabilization properties,retention period,and slump loss of SCC systems in their fresh sta... The aim and scope of the present study were to determine the efficacy of UFFA in evaluating the workability,static and dynamic stabilization properties,retention period,and slump loss of SCC systems in their fresh state,as well as their compressive strength at various ages.Microstructure(SEM and XRD)of blended SCC systems were studied.Also,the thermogravimetry behavior of blended SCC specimens were researched.According to the evaluated results,incorporating up to 20%UFFA into fresh concrete improved its performance due to its engineered fine particle size and spherical geometry,both of which contribute to the enhancement of characteristics.Blends of 25%and 30%of UFFA show effect on the water-binder ratio and chemical enhancer dosage,resulting in a loss of homogeneity in fresh SCC systems.The reduced particle size,increased amorphous content,and increased surface area all contribute to the pozzolanic reactivity of the early and later ages,resulting in denser packing and thus an increase in compressive strength.The experimental results indicate that UFFA enhances the properties of SCC in both its fresh and hardened states,which can be attributed to the particles’fineness and their relative effect on SCC. 展开更多
关键词 ultra fine fly ash self-compacting concrete WORKABILITY SEGREGATION compressive strength microstructure TGA
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杨木与甘蔗渣共热解的研究
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作者 杨琳 刘莹 +1 位作者 杨森 张璇 《农业科学》 2023年第7期670-676,共7页
本研究利用热重分析仪研究了甘蔗渣和杨木的热解特性,并分析了混合比例对甘蔗渣和杨木共热解特性的影响,并利用热裂解仪–气相色谱/质谱联用仪(Py-GC/MS)研究了甘蔗渣和杨木共热解的产物分布。结果表明,杨木的热解过程主要分为三个阶段... 本研究利用热重分析仪研究了甘蔗渣和杨木的热解特性,并分析了混合比例对甘蔗渣和杨木共热解特性的影响,并利用热裂解仪–气相色谱/质谱联用仪(Py-GC/MS)研究了甘蔗渣和杨木共热解的产物分布。结果表明,杨木的热解过程主要分为三个阶段,而甘蔗渣的热解过程则被分为四个阶段。甘蔗渣的添加无法改变起始热解温度但使得最大热解速率对应温度向高温区移动,这说明共混会延缓纤维素的热解。共混物的半纤维素热解阶段表观活化能相较于杨木和甘蔗渣更高,这说明共混抑制了半纤维素的热解。而当杨木含量较高的情况下,纤维素热解活化能最低,这表明杨木和甘蔗渣共热解的纤维素热解阶段存在协同作用。此外,杨木和甘蔗渣的共热解还对于醛类化合物的生成具有协同作用,可以提高其相对含量。 展开更多
关键词 杨木 甘蔗渣 共热解 TGA 动力学
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玉米TGA转录因子家族全基因组鉴定及盐胁迫相关表达分析
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作者 孟新超 殷恒梅 +4 位作者 张兴政 汪林林 曹昆 朴京培 刘剑锋 《江西农业大学学报》 CAS CSCD 北大核心 2023年第3期631-642,共12页
[目的]TGA基因家族是玉米中的一类转录因子,是植物生长发育、响应生物胁迫和非生物胁迫的关键调控因子。玉米是我国重要粮食作物,其胁迫响应分子机制的研究对于玉米生产具有重要理论意义。[方法]利用生物信息学方法对玉米TGA基因家族的... [目的]TGA基因家族是玉米中的一类转录因子,是植物生长发育、响应生物胁迫和非生物胁迫的关键调控因子。玉米是我国重要粮食作物,其胁迫响应分子机制的研究对于玉米生产具有重要理论意义。[方法]利用生物信息学方法对玉米TGA基因家族的理化性质、亚细胞定位、进化关系、染色体定位与共线性、基因结构和基因表达进行分析。利用高通量转录组数据,明确各基因在玉米不同组织、不同发育时期的表达水平以及盐胁迫条件下的响应,利用qRT-PCR对盐胁迫响应的TGA基因进行表达验证。[结果]通过同源比对在玉米全基因组中共筛选到21个TGAs同源序列,都包含bZIP结构域和DOG1结构域,蛋白定位的预测均定位于细胞核。进化分析显示ZmTGA家族基因可划分为5个群组。共线性分析显示ZmTGA家族成员中有7对基因在进化过程中存在共线性关系,玉米ZmTGA家族与单子叶植物(水稻)TGA基因组成共线性基因数量大于其与双子叶植物(大豆和拟南芥)对比的数量。转录组数据分析结果显示,ZmTGAs在不同组织中表达模式不同,ZmTGAs家族基因普遍在根中表达。基因表达分析显示ZmTGA7和ZmTGA11受盐胁迫诱导表达。[结论]利用生物信息学等方法在玉米全基因组中共筛选到21个ZmTGA同源序列,并分析了基因、蛋白结构及理化性质等。共线性分析也发现7对基因在进化过程中存在共线性关系。组织特异性表达分析表明在不同组织中表达模式不同,暗示ZmTGAs在玉米生长发育过程中对不同组织起调控作用。盐胁迫转录组及表达水平分析结果显示ZmTGA7和ZmTGA11其表达受高盐胁迫诱导,可能参与玉米盐胁迫响应调控。 展开更多
关键词 玉米 TGA 进化分析 表达分析
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淋洗类化妆品中塑料微珠的测定 被引量:2
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作者 洪灯 谢文 +3 位作者 胡起立 高丽红 徐可 刘婷 《香料香精化妆品》 CAS 2023年第6期147-151,共5页
采用乙醇水溶液对洁面乳、沐浴露、磨砂膏等淋洗类化妆品进行加热分散,定性滤纸对固体颗粒进行过滤提取,红外光谱定性分析,并对红外光谱鉴定为塑料材质的颗粒再进行热重分析(TGA)和差示扫描量热分析(DSC),提高定性分析结果的可靠性。结... 采用乙醇水溶液对洁面乳、沐浴露、磨砂膏等淋洗类化妆品进行加热分散,定性滤纸对固体颗粒进行过滤提取,红外光谱定性分析,并对红外光谱鉴定为塑料材质的颗粒再进行热重分析(TGA)和差示扫描量热分析(DSC),提高定性分析结果的可靠性。结果表明:10种淋洗类化妆品中含有固体颗粒,其中1种固体颗粒鉴别为聚乙烯塑料,其余9种为植物纤维素。采用激光粒度仪对聚乙烯塑料的粒度分布进行了考察,80%微粒粒度集中在150~600μm;采用超景深显微镜对聚乙烯塑料的微观尺度进行分析,塑料颗粒呈现明显球形状态。该标准化的分析操作方法能满足淋洗类化妆品中塑料微珠的定性测定需求,并为淋洗类化妆品中塑料微珠的管控提供技术支撑。 展开更多
关键词 红外光谱 淋洗类化妆品 塑料微珠 热重分析(TGA) 差示扫描量热分析(DSC) 粒度分析
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谷子TGA转录因子家族全基因组鉴定与分析
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作者 高倩 秦迎迎 杨致荣 《山西农业科学》 2023年第5期469-477,共9页
TGA转录因子在植物器官发育和抗病反应中发挥着重要作用。为了探究C4模式植物谷子TGA基因家族成员的结构和功能,为进一步探索TGA转录因子的生物学功能提供理论基础,以拟南芥TGA基因家族的氨基酸序列为参考序列,从xiaomi基因组中鉴定出16... TGA转录因子在植物器官发育和抗病反应中发挥着重要作用。为了探究C4模式植物谷子TGA基因家族成员的结构和功能,为进一步探索TGA转录因子的生物学功能提供理论基础,以拟南芥TGA基因家族的氨基酸序列为参考序列,从xiaomi基因组中鉴定出16个TGA基因,命名为SiTGA1~SiTGA16,并利用生物信息学软件对其结构和表达模式进行分析。结果表明,SiTGAs在9条染色体上均有分布,其中在2号和5号染色体上均含有3个基因;在3、4号和6号染色体分别分布有2个基因;在1、7、8号和9号染色体上分别仅有1个基因。理化性质分析结果显示,SiTGAs的二级结构主要为α-螺旋,无规卷曲次之;SiTGAs亚细胞主要定位在细胞核。进化关系结果显示,16个SiTGAs分属6个亚类,这些亚家族分别含有4、4、1、5、1、1个基因,与高粱的亲缘关系最近,其中亲缘关系近的SiTGAs的基因结构、保守基序、保守结构域具有保守性。TGA基因家族成员的进化关系及SiTGAs在谷子中的表达模式结果显示,谷子TGA基因家族在谷子的抗逆反应、抗病反应、花器官发育以及茎尖、芽尖分生组织调控和根尖干细胞群维持中起着重要作用。 展开更多
关键词 谷子 xiaomi TGA转录因子 基因家族 生物信息学
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Flexible Biofoams Based on Furanics and Fatty Acids Esterified Tannin
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作者 Elham Azadeh Ummi Hani Abdullah +3 位作者 Christine Gerardin Antonio Pizzi Philippe Gerardin Cesar Segovia 《Journal of Renewable Materials》 EI 2023年第10期3625-3645,共21页
Water repellant,flexible biofoams using tannin esterified with various fatty acid chains,namely lauric,palmitic and oleic acids,by reaction with lauryl chloride,palmitoyl chloride,and oleyl chloride were developed and... Water repellant,flexible biofoams using tannin esterified with various fatty acid chains,namely lauric,palmitic and oleic acids,by reaction with lauryl chloride,palmitoyl chloride,and oleyl chloride were developed and their characteristics compared with the equivalently esterified rigid biofoams.Glycerol,while initially added to control the reaction temperature,was used as a plasticizer yielding flexible biofoams presenting the same water repellant character that the equivalent rigid foams.Acetaldehyde was used as the cross-linking agent instead of formaldehyde,as it showed a better performance with the esterified tannin.The compression results showed a significant decrease of the Modulus of Elasticity(MOE)of the flexible foams in relation to that of the rigid foams,confirming their flexible character.The lauryl-and palmitoyl-esterified biofoams presented similar mechanical properties,while the oleyl-esterified biofoam presented different mechanical and morphological result not really showing the expected flexibility.Both the esterified rigid and flexible tannin-based biofoams showed good water resistance and their sessile drop contact angle analysis as a function of time confirmed this characteristic.Scanning Electron Microscope(SEM)analysis showed the flexible foams to present a higher proportion of closed cells than the rigid foams.Conversely,the cells depth of the flexible foams was lower than that of the rigid foam.As regards their thermal resistance,the flexible foams showed a slight loss of mass compared to the rigid ones without glycerol.Both types of foams presented much lower surface friability of non-esterified rigid foams. 展开更多
关键词 Flexible tannin-furanic foams esterified tannins water repellence TGA SEM compression
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超声造影、DWI及血清TPO-Ab、TSH、TGA对甲状腺乳头状癌的诊断价值分析
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作者 赵亚影 禹海贺 +2 位作者 张圳锋 张东显 柴青芬 《中国CT和MRI杂志》 2023年第10期80-83,共4页
目的 探讨超声造影(CEUS)、磁共振扩散加权成像(DWI)及血清抗甲状腺过氧化物酶抗体(TPO-Ab)、促甲状腺激素(TSH)、抗甲状腺球蛋白抗体(TGA)对甲状腺乳头状癌(PTC)的诊断价值。方法 收集我院2019年1月至2022年1月92例经病理证实为PTC患... 目的 探讨超声造影(CEUS)、磁共振扩散加权成像(DWI)及血清抗甲状腺过氧化物酶抗体(TPO-Ab)、促甲状腺激素(TSH)、抗甲状腺球蛋白抗体(TGA)对甲状腺乳头状癌(PTC)的诊断价值。方法 收集我院2019年1月至2022年1月92例经病理证实为PTC患者作为PTC组,92例为甲状腺良性肿瘤患者作为良性组。比较两组的血清TPO-Ab、 TSH、TG A水平、超声征象与表观扩散系数(ADC)值,评估血清TPO-Ab、TSH、TGA、CEUS以及DWI单项以及联合诊断与病理诊断结果 ,同时分析血清TPOAb、TSH、TGA、CEUS以及DWI对PTC的诊断价值。结果 PTC组的血清TPO-Ab、TSH、TGA水平均高于良性组(P<0.05);PTC组的淋巴肿大、钙化、回声不均匀、边界不清、形态不规则比例高于良性组(P<0.05);PTC组血流分级以Ⅱ-Ⅲ级为主,良性组以Ⅰ-Ⅱ级为主,两组血流分级比较,差异有统计学意义(P<0.05);PTC组的ADC值低于良性组(P<0.05)。本研究经Kappa一致性检测结果 显示,血清TPO-Ab诊断结果 和病理诊断结果 为一致性中等(P<0.05);血清TSH、TGA、CEUS、DWI诊断结果 和病理诊断结果 为高度一致性(P<0.05);联合检测诊断结果 和病理诊断结果 为一致性完全相同(P<0.05),并且联合检测的一致性最高。联合诊断的灵敏度(86.96%)、阴性预测值(86.36%)分别高于血清TPO-Ab、TSH、TGA、CEUS以及DWI的单一指标诊断。结论 PTC患者血清TPO-Ab、TSH、TGA水平升高,CEUS、DWI联合血清TPO-Ab、TSH、TGA在PTC诊断中具有较高的临床应用价值,可以提高诊断准确率。 展开更多
关键词 CEUS DWI TPO-AB TSH TGA 甲状腺乳头状癌 诊断价值
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Preparation and Investigation of Mechanical and Physical Properties of Flax/Glass Fabric Reinforced Polymer Hybrid Composites
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作者 Sayed Hasan Mahmud Md. Washim Akram +1 位作者 Md. Fuad Ahmed Md. Atik Bin Habib 《Journal of Textile Science and Technology》 2023年第3期165-182,共18页
Synthetic reinforced composites affect the environment adversely and have become a global concern, causing increased natural composite demand for sustainability and cost effectiveness. Glass is a popular material that... Synthetic reinforced composites affect the environment adversely and have become a global concern, causing increased natural composite demand for sustainability and cost effectiveness. Glass is a popular material that is highly consumed in reinforced composites for its superior mechanical strength. As opposed to that, flax obtained from flax stalks can be used as an alternative reinforcing material with synthetic fibers to minimize manmade fiber consumption. Hence, this research work addresses a few flax/glass-reinforced hybrid composites by using a thermoset polyester matrix. Here, six categories of samples are made, like neat flax, neat glass, and flax/glass fabric reinforced hybrid composite, followed by different stacking layer sequences and hand layout techniques during processing. Afterwards, the mechanical behavior, thermal stability, morphological behavior, and water absorption of hybrid samples were investigated. Among the developed samples, neat glass (NG) composite exhibits superior mechanical properties, while neat flax (NF) shows the lowest result. It is apparent that the mechanical properties and thermal stability of hybrid samples are in between NF and NG because, by adding glass with flax fabric, the strength of hybrid samples is increased. Moreover, it is noticeable that, due to multiple stacking layers of flax and glass, hybrid 3 and hybrid 4 show better strength than consecutive single stacking layers in hybrid 1 and hybrid 2. Among all hybrid composites, the H4 shows comparatively better mechanical and thermal properties due to having the glass layers on the outermost surface. In summary, this research work demonstrated the feasibility of flax fabric with glass fabric as a reinforced hybrid composite that can be used in automobile inner bodies, household furnishing, and home interior decoration. 展开更多
关键词 Flax-Glass Fabric Reinforced Composites Mechanical Properties SEM TGA Polyester Resin
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Preparation and Investigation of Mechanical and Physical Properties of Flax/Glass Fabric Reinforced Polymer Hybrid Composites
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作者 Sayed Hasan Mahmud Md. Washim Akram +1 位作者 Md. Fuad Ahmed Md. Atik Bin Habib 《Journal of Flow Control, Measurement & Visualization》 2023年第3期165-182,共18页
Synthetic reinforced composites affect the environment adversely and have become a global concern, causing increased natural composite demand for sustainability and cost effectiveness. Glass is a popular material that... Synthetic reinforced composites affect the environment adversely and have become a global concern, causing increased natural composite demand for sustainability and cost effectiveness. Glass is a popular material that is highly consumed in reinforced composites for its superior mechanical strength. As opposed to that, flax obtained from flax stalks can be used as an alternative reinforcing material with synthetic fibers to minimize manmade fiber consumption. Hence, this research work addresses a few flax/glass-reinforced hybrid composites by using a thermoset polyester matrix. Here, six categories of samples are made, like neat flax, neat glass, and flax/glass fabric reinforced hybrid composite, followed by different stacking layer sequences and hand layout techniques during processing. Afterwards, the mechanical behavior, thermal stability, morphological behavior, and water absorption of hybrid samples were investigated. Among the developed samples, neat glass (NG) composite exhibits superior mechanical properties, while neat flax (NF) shows the lowest result. It is apparent that the mechanical properties and thermal stability of hybrid samples are in between NF and NG because, by adding glass with flax fabric, the strength of hybrid samples is increased. Moreover, it is noticeable that, due to multiple stacking layers of flax and glass, hybrid 3 and hybrid 4 show better strength than consecutive single stacking layers in hybrid 1 and hybrid 2. Among all hybrid composites, the H4 shows comparatively better mechanical and thermal properties due to having the glass layers on the outermost surface. In summary, this research work demonstrated the feasibility of flax fabric with glass fabric as a reinforced hybrid composite that can be used in automobile inner bodies, household furnishing, and home interior decoration. 展开更多
关键词 Flax-Glass Fabric Reinforced Composites Mechanical Properties SEM TGA Polyester Resin
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Matrix-Material Fabrication Technique and Thermogravimetric Analysis of Banana Fiber Reinforced Polypropylene Composites
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作者 Nazrul Islam M.A Gafur 《Journal of Building Material Science》 2023年第2期15-24,共10页
From the environmental consideration,it would be very interesting to use natural fibers such as banana,jute or coir as reinforcement materials instead of artificial fibers or any kind of synthetic materials.Natural fi... From the environmental consideration,it would be very interesting to use natural fibers such as banana,jute or coir as reinforcement materials instead of artificial fibers or any kind of synthetic materials.Natural fibers have many advantages over synthetic ones.Polypropylene banana fiber composites(PPBC)are prepared using untreated and alkali-treated banana fibers at 10-25%by weight of the fiber loading.The thermal properties of polypropylene natural fiber composites are very important for technological uses.Thermogravimetric measurements show that the incorporation of banana fiber into PP enhances the thermal stability of composites containing treated fibers,in comparison with untreated fibers.A composite of biodegradable polypropylene(PP)reinforced with short banana natural fibers was prepared by melt blending followed by a hot press molding system.The thermal properties of matrix materials were studied using thermogravimetric analyzers TGA units.It is observed that the introduction of short banana fibers slightly improved the thermo oxidative stability of PP-banana composites.Physical and chemical changes occurred through dehydration,phase transition,molecular orientation,crystallinity disruption,oxidation and decomposition,and incorporation of several functional groups.Systematic investigations of the thermal behavior of polymers in gas,vacuum or inert atmosphere give the knowledge of how change takes place in polymers.To understand such changes thermogravimetric analysis(TGA)and thermal analysis(TG)were performed.It is observed reinforcement of short banana fiber leads to little improvement in the thermooxidative stability of PPBC.Due to the enhancement of thermo-mechanical properties,such composites may be used as building materials namely roof materials,selling materials and many other engineering applications. 展开更多
关键词 Polypropylene banana composites(PPBC) Natural fiber Oxidative stability Thermogravimetric analysis(TGA) DECOMPOSITION
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天能加速全球化战略——天能全球化联盟(TGA)正式成立
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作者 天能 《中国自行车》 2023年第1期57-57,共1页
2022年10月21日,由天能股份集团发起,学术、法律、金融、产品、生产技术以及管理运营等领域的各家企业及专家代表共同响应参与的天能全球化联盟(TGA)在深圳正式成立。通商律师事务所、瑞穗银行(中国)有限公司、北京大学、伟赛力管理咨... 2022年10月21日,由天能股份集团发起,学术、法律、金融、产品、生产技术以及管理运营等领域的各家企业及专家代表共同响应参与的天能全球化联盟(TGA)在深圳正式成立。通商律师事务所、瑞穗银行(中国)有限公司、北京大学、伟赛力管理咨询有限公司、中建材海外经济合作有限公司、江西巴特威新能源科技有限公司、天能新能源(湖州)有限公司、天能帅福得能源股份有限公司、浙江天能资源循环科技有限公司、浙江集秀元智能装备有限公司等50多家单位成为首批会员单位。 展开更多
关键词 管理运营 律师事务所 资源循环 全球化战略 新能源 能源股份 智能装备 TGA
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