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电场对辣根过物氧化酶紫外-可见光谱及其活性有效期的影响
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作者 许强 杨科利 高红艳 《种子》 CSCD 北大核心 2009年第8期48-50,共3页
辣根过氧化物酶经电场处理,测试处理放置12 d辣根过氧化物酶的紫外-可见光谱和活性。结果表明:辣根过氧化物酶的紫外-可见光谱发生了明显变化,说明电场可以较长时间的影响酶蛋白的构象;辣根过氧化物酶活性普遍降低,酶活性降低可能是由... 辣根过氧化物酶经电场处理,测试处理放置12 d辣根过氧化物酶的紫外-可见光谱和活性。结果表明:辣根过氧化物酶的紫外-可见光谱发生了明显变化,说明电场可以较长时间的影响酶蛋白的构象;辣根过氧化物酶活性普遍降低,酶活性降低可能是由酶构象的改变引起。研究结果对解释静电宏观生物效应具有重要意义。 展开更多
关键词 电场 辣根过物氧化酶 紫外-可见光谱 构象 活性
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水平二(四年级)《跨跳过物的练习方法》教学设计
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《体育教学》 2016年第12期18-19,共2页
一、指导思想本课以“健康第一”为指导思想,以《义务教育体育与健康课程标准(2011版)》为依据,结合《浙江省义务教育体育与健康课程指导纲要》精神,以“技术、体能、运用”三维度构建单元策略,在课堂教学中注重“教材三个一”,关注... 一、指导思想本课以“健康第一”为指导思想,以《义务教育体育与健康课程标准(2011版)》为依据,结合《浙江省义务教育体育与健康课程指导纲要》精神,以“技术、体能、运用”三维度构建单元策略,在课堂教学中注重“教材三个一”,关注常态课的七个基本要求,在实施过程中,在教学设计上,针对学生身心特点,选择更多的练习方法,在玩中学,学中练,提升教学实效, 展开更多
关键词 水平二 跨跳过物:练习方法 教学设计
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摹略万物之然——后期墨家认识论
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作者 董志铁 《山东师范大学学报(人文社会科学版)》 北大核心 2003年第6期10-14,共5页
 后期墨家在继承墨子唯物思想的基础上,论述了认识的基础、认识的过程及认识过程中的阶段性、认识所得知识的不同来源及种类,批判了以往认识论中的一些错误命题。后期墨家的认识论系统,感性、理性认识并重,理性认识以感性认识为基础。...  后期墨家在继承墨子唯物思想的基础上,论述了认识的基础、认识的过程及认识过程中的阶段性、认识所得知识的不同来源及种类,批判了以往认识论中的一些错误命题。后期墨家的认识论系统,感性、理性认识并重,理性认识以感性认识为基础。这种认识论对认识主体作用的强调有重要的理论与现实意义。 展开更多
关键词 后期墨家认识论 "过物" "论" "为知"
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Freestanding oxide membranes:synthesis,tunable physical properties,and functional devices
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作者 Ao Wang Jinfeng Zhang Lingfei Wang 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期2-17,1,I0002,共18页
The study of oxide heteroepitaxy has been hindered by the issues of misfit strain and substrate clamping,which impede both the optimization of performance and the acquisition of a fundamental understanding of oxide sy... The study of oxide heteroepitaxy has been hindered by the issues of misfit strain and substrate clamping,which impede both the optimization of performance and the acquisition of a fundamental understanding of oxide systems.Recently,however,the development of freestanding oxide membranes has provided a plausible solution to these substrate limitations.Single-crystalline functional oxide films can be released from their substrates without incurring significant damage and can subsequently be transferred to any substrate of choice.This paper discusses recent advancements in the fabrication,adjustable physical properties,and various applications of freestanding oxide perovskite films.First,we present the primary strategies employed for the synthesis and transfer of these freestanding perovskite thin films.Second,we explore the main functionalities observed in freestanding perovskite oxide thin films,with special attention to the tunable functionalities and physical properties of these freestanding perovskite membranes under varying strain states.Next,we encapsulate three representative devices based on freestanding oxide films.Overall,this review highlights the potential of freestanding oxide films for the study of novel functionalities and flexible electronics. 展开更多
关键词 freestanding oxide membranes transition metal oxides thin films electronic devices
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The application of metal-organic frameworks and their derivatives for lithium-ion capacitors
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作者 ZHAO Sha-sha ZHANG Xiong +5 位作者 LI Chen AN Ya-bin HU Tao WANG Kai SUN Xian-zhong MA Yan-wei 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期872-895,共24页
There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of t... There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of traditional rechargeable batteries with the superior power density and long life of supercapacitors(SCs).Nevertheless,the development of LICs is still hampered by limited kinetic processes and capacity mismatch between the cathode and anode.Metal-organic frameworks(MOFs)and their derivatives have received significant attention because of their extensive specific surface area,different pore structures and topologies,and customizable functional sites,making them compelling candidate materials for achieving high-performance LICs.MOF-derived carbons,known for their exceptional electronic conductivity and large surface area,provide improved charge storage and rapid ion transport.MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability.Additionally,MOF-derived metal compounds/carbons provide combined effects that increase both the capacitive and Faradaic reactions,leading to a superior overall performance.The review begins with an overview of the fundamental principles of LICs,followed by an exploration of synthesis strategies and ligand selection for MOF-based composite materials.It then analyzes the advantages of original MOFs and their derived materials,such as carbon materials and metal compounds,in enhancing LIC performance.Finally,the review discusses the major challenges faced by MOFs and their derivatives in LIC applications and offers future research directions and recommendations. 展开更多
关键词 Lithium-ion capacitors MOFS Transition metal oxide Energy density Power density
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四物过敏煎联合驷马穴埋针治疗小儿慢性荨麻疹30例 被引量:5
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作者 李云海 文希 吴杰妍 《辽宁中医杂志》 CAS 2021年第9期181-184,共4页
目的明确四物过敏煎联合驷马穴埋针治疗小儿慢性荨麻疹的临床疗效。方法将90例慢性荨麻疹儿童患者随机分为对照组、中药组、针药组,每组30例。对照组给予地氯雷他定治疗;中药组给予四物过敏煎治疗,针药组给予四物过敏煎联合驷马穴埋针治... 目的明确四物过敏煎联合驷马穴埋针治疗小儿慢性荨麻疹的临床疗效。方法将90例慢性荨麻疹儿童患者随机分为对照组、中药组、针药组,每组30例。对照组给予地氯雷他定治疗;中药组给予四物过敏煎治疗,针药组给予四物过敏煎联合驷马穴埋针治疗,两组均治疗4周。分别于治疗前、治疗后评价临床疗效;采用ELISA法检测血清中IgE及C3、C4补体的表达;统计治疗过程中的不良反应,随访1个月计算复发率。结果治疗后,对照组总有效率66.7%(20/30),中药组总有效率90.0%(27/30),针药组总有效率93.3%(28/30)。3组比较,中药组和针药组总有效率优于对照组(P<0.01),而中药组和针药组之间差异无统计学意义(P>0.05)。治疗后3组IgE水平均较本组治疗前明显降低(P<0.01),中药组和针药组低于对照组(P<0.01),针药组低于中药组(P<0.01)。除对照组治疗后C4水平无明显变化外,其余C3、C4水平均较本组治疗前明显升高(P<0.01或P<0.05),中药组和针药组高于对照组(P<0.01),针药组高于中药组(P<0.05)。治疗后对照组有1例病人出现口干,2例病人出现嗜睡,中药组和针药组患者均无明显不良反应发生。1个月后,对照组中有效20例,复发3例,复发率15%;中药组有效27例,复发1例,复发率3.7%;针药组有效28例,复发1例,复发率3.5%。中药组和针药组复发率明显低于对照组(P<0.01)。结论该研究发现四物过敏煎联合驷马穴埋针治疗小儿慢性荨麻疹,可明显减轻荨麻疹症状,降低血清IgE表达,提高血清补体C3、C4水平,降低复发率,值得临床推广应用。 展开更多
关键词 过敏煎 慢性荨麻疹 小儿 驷马穴 埋针 疗效
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益智方对急性衰老模型小鼠记忆障碍的作用 被引量:3
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作者 沈丽霞 王继峰 《中国老年学杂志》 CAS CSCD 北大核心 2007年第3期206-207,共2页
目的探讨益智方(YZF)对AlCl3致急性衰老模型小鼠记忆障碍的保护作用及其机制。方法应用AlCl3制备小鼠记忆障碍模型,采用避暗试验和跳台试验,观察不同剂量YZF对记忆障碍模型小鼠的保护作用,并对各剂量组小鼠进行脑组织超氧化物歧化酶(SOD... 目的探讨益智方(YZF)对AlCl3致急性衰老模型小鼠记忆障碍的保护作用及其机制。方法应用AlCl3制备小鼠记忆障碍模型,采用避暗试验和跳台试验,观察不同剂量YZF对记忆障碍模型小鼠的保护作用,并对各剂量组小鼠进行脑组织超氧化物歧化酶(SOD)活性及血浆和脑组织谷胱甘肽过氧化物酶(GSH-Px)活性测定。结果YZF两个剂量组均能明显改善记忆障碍,增加SOD和GSH-Px活性。结论YZF对AlCl3致急性衰老小鼠记忆障碍具有保护作用,其作用机制可能是通过增强GSH-Px和SOD活性,清除氧自由基对中枢神经系统神经细胞的损伤。 展开更多
关键词 益智方(YZF) ALCL3 学习记忆 超氧化歧化酶(SOD) 谷胱甘肽过物酶(GSH-Px)
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Effects of Drought Stress on Activity of POD and CAT in Wheat during Generation Period 被引量:5
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作者 陈军 高贵珍 +2 位作者 方雪梅 张兴桃 吕晓娇 《Agricultural Science & Technology》 CAS 2013年第11期1529-1531,共3页
[Objective] This study aimed to investigate the changes in activity of POD and CAT in wheat during generation period under drought stress. [Method] Four wheat cultivars, including Yunong 51, Zhoumai 22, Jimai 19 and H... [Objective] This study aimed to investigate the changes in activity of POD and CAT in wheat during generation period under drought stress. [Method] Four wheat cultivars, including Yunong 51, Zhoumai 22, Jimai 19 and Huaimai 22, were selected as experimental materials and cultured under drought stress simulated by different concentrations of PEG6000, to determine the activity of POD and CAT. [Result] POD and CAT activity in wheat during generation period increased gradual y under stress of 5% and 15% PEG6000 from 0 to 120 h; POD and CAT activity in wheat under stress of 15% PEG6000 increased more compared with that under stress of 5% PEG6000; POD and CAT activity in wheat under stress of 25% and 35% PEG6000 increased first and then decreased. Stress duration significantly af-fected the activity of POD and CAT in wheat during generation period. [Conclusion] This study provided theoretical references for breeding drought-tolerant wheat. 展开更多
关键词 WHEAT Germination period POD activity -CAT activity
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Effects of Manganese Stress on POD Activities and Isozymes of Soybean 被引量:7
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作者 王廷璞 王静 孙晓艳 《Agricultural Science & Technology》 CAS 2011年第1期33-36,共4页
[Objective]The aim was to discuss the internal reason of some inherited characteristics and genetic differences of different varieties of poisoned soybeans in molecule level.[Method]Soybeans were cultivated by water c... [Objective]The aim was to discuss the internal reason of some inherited characteristics and genetic differences of different varieties of poisoned soybeans in molecule level.[Method]Soybeans were cultivated by water culture and treated for 10 days under natural light conditions.The influence of increasing concentration of manganese(0-120 mg/L) on the POD activities and isoenzyme of roots stems and leaves of soybean were studied.[Result]Results showed that the POD activities in roots,stems and leaves firstly increased and then decreased with increasing concentration of manganese.There were differences in the response of POD isoenzyme zymograms to manganese stress in different organs,the POD isoenzyme activity and quantities of soybean roots changed apparently when the manganese concentration increased,while the POD isoenzyme activity and quantities of soybean stems and leaves kept stable.[Conclusion]The isoenzyme zymograms changes of different organs of soybean were related to the resistance of soybean to manganese stress. 展开更多
关键词 MANGANESE POD ISOENZYME
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Effects of Catalase and Ascorbate Peroxidase on the Root Growth of Rice under Cadmium Stress 被引量:9
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作者 宋新华 王凯 +1 位作者 郭蕾蕾 赵凤云 《Agricultural Science & Technology》 CAS 2011年第9期1256-1259,共4页
[Objective] The research aimed to study the correlations between catalase(CAT) and ascorbate peroxidase(ASP) and the growth and development of rice roots under cadmium stress.[Method] Taking rice variety Zhonghua ... [Objective] The research aimed to study the correlations between catalase(CAT) and ascorbate peroxidase(ASP) and the growth and development of rice roots under cadmium stress.[Method] Taking rice variety Zhonghua No.11 as materials,the changes of rice seedlings under the treatment conditions of Cd,Cd+CAT inhibitor,Cd+APX inhibitor were studied.[Result] Under Cd stress,inhibition of CAT activity caused the significant inhibition on the growth of aerial parts,decreased the number of adventitious roots and lateral roots,but it can significant promote the elongation growth of adventitious roots and lateral roots.Moreover,the length of the first lateral root from root tip on the primary roots and adventitious roots was also increased than control.When APX activity was inhibited,the growth changes of rice were similar with that treated by CAT inhibitor.[Conclusion] CAT and APX may play important roles in the regulation of rice root system growth in both non-stress and Cd-stressed rice 展开更多
关键词 Cd stress CATALASE Ascorbate peroxidase
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Heterogeneous catalytic activation of peroxymonosulfate for efficient degradation of organic pollutants by magnetic Cu^0/Fe_3O_4 submicron composites 被引量:10
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作者 聂刚 黄佳 +3 位作者 胡冶州 丁耀彬 韩小彦 唐和清 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期227-239,共13页
Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-pr... Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-prepared magnetic Cu^0/Fe3O4 submicron composites were composed of Cu^0 and Fe3O4 crystals and had an average size of approximately 220 nm.The Cu^0/Fe3O4 composites could efficiently catalyze the activation of PMS to generate singlet oxygen,and thus induced the rapid degradation of rhodamine B,methylene blue,orange Ⅱ,phenol and 4-chlorophenol.The use of0.1 g/L of the Cu^0/Fe3O4 composites induced the complete removal of rhodamine B(20 μmol/L) in15 min,methylene blue(20 μmol/L) in 5 min,orange Ⅱ(20 μmol/L) in 10 min,phenol(0.1mmol/L) in 30 min and 4-chlorophenol(0.1 mmol/L) in 15 min with an initial pH value of 7.0 and a PMS concentration of 0.5 mmol/L.The total organic carbon(TOC) removal higher than 85%for all of these five pollutants was obtained in 30 min when the PMS concentration was 2.5 mmol/L.The rate of degradation was considerably higher than that obtained with Cu^0 or Fe3O4 particles alone.The enhanced catalytic activity of the Cu^0/Fe3O4 composites in the activation of PMS was attributed to the synergistic effect of the Cu^0 and Fe3O4 crystals in the composites.Singlet oxygen was identified as the primary reactive oxygen species responsible for pollutant degradation by electron spin resonance and radical quenching experiments.A possible mechanism for the activation of PMS by Cu^0/Fe3O4 composites is proposed as electron transfer from the organic pollutants to PMS induces the activation of PMS to generate ^1O2,which induces the degradation of the organic pollutants.As a magnetic catalyst,the Cu^0/Fe3O4 composites were easily recovered by magnetic separation,and exhibited excellent stability over five successive degradation cycles.The present study provides a facile and green heterogeneous catalysis method for the oxidative removal of organic pollutants. 展开更多
关键词 Heterogeneous catalysis Magnetic Cu^0/Fe3O4 composite PEROXYMONOSULFATE Singlet oxygen Oxidative degradation
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Occurrences of Yttrium in Soil and Its Potential Impacts on Paddy Rice Triticum aestivum 被引量:1
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作者 冯秀娟 张素贞 +3 位作者 朱易春 马彩云 潘阳 高咪 《Agricultural Science & Technology》 CAS 2013年第12期1783-1787,共5页
[Objective] The effects of yttrium nitrate (YNO3) on biomass and antioxi- dant systems of paddy rice (Yttrium (Y); Oxidative stress; Dismutases (SOD); Per- oxidases (POD), Catalases (CAT), Paddy rice (Trit... [Objective] The effects of yttrium nitrate (YNO3) on biomass and antioxi- dant systems of paddy rice (Yttrium (Y); Oxidative stress; Dismutases (SOD); Per- oxidases (POD), Catalases (CAT), Paddy rice (Triticum aestivum)) together with the occurrences of Y in soils were investigated to assess its ecotoxicological effects on plant. [Method]Y solutions with various concentrations were sprinkled on soil sam- ples, which were well mixed and then put into culture dishes to culture paddy rice seeds for further evaluation. [Result] The results indicated that 25-100 mg/kg Y treatments significantly increased the biomass (total weight, root weight, shoot weight and leaf weight), chlorophyll (CHL) content and protein content of paddy rice, whereas 200-800 mg/kg Y treatments had a converse effect. Similarly, biomarker for the antioxidant systems including superoxide dismutases (SOD), peroxidases (POD) and catalases (CAT) all exhibited similar trends in both shoots and roots of paddy rice. At the same time, the malonaldehyde (MDA) content increased at from 25 to 100 mg/kg and decreased with concentrations of Y from 100 to 800 mg/kg in both shoots and roots of paddy rice. This indicated that Y could stimulate the growth of plant at low concentration, but inhibit the growth at relatively high concen- tration. [Conclusion] The levels of Y were 641+49, 328_+16 and 473_+40 mg/kg in soils collected from mining area, farmland and navel orange orchard respectively. The levels of Y in the investigated area were higher than the benefit level (100 mg/kg), which could cause low biomass as well as low activity of SOD, POD and CAT in paddy rice. Therefore, a more careful use of Y is necessary in crop management. 展开更多
关键词 Yttrium (Y) Oxidative stress Dismutases (SOD) Peroxidases (POD) Catalases (CAT) Paddy rice (Yttrium (Y) Oxidative stress Dismutases (SOD) Per- oxidases (POD) Catalases (CAT) Paddy rice (Triticum aestivum))
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Study on the Cloning and Isolation of sus scrofa GPX2 Gene by RACE Method 被引量:2
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作者 赵华 周继昌 +2 位作者 李俊刚 赵莹 王康宁 《Agricultural Science & Technology》 CAS 2008年第1期24-28,共5页
[Objective] Using molecular biotechnology to clone the sus scrofa GPX2 gene. [Method] Using total RNA of sus scrofa duodenum as template, degenerated primer pairs were designed according to the homology alignment anal... [Objective] Using molecular biotechnology to clone the sus scrofa GPX2 gene. [Method] Using total RNA of sus scrofa duodenum as template, degenerated primer pairs were designed according to the homology alignment analysis of GPX2 gene of human, rat, mouse, dog and cattle. A sus scrofa GPX2 gene sequence of 330 bp was obtained by RT-PCR application method. Primes were designed respectively according to the known sequence, sus scrofa GPX2 gene was isolated and cloned by 3-RACE and 5-RACE method and analyzed the gene sequence. [Result] A mRNA sequence of 924 bp was successfully cloned and isolated in this research. This sequence contained complete 3'end and had higher sequence homology with human,mouse,cattle and dog GPX2 gene, and there was codon called TGA which encoding Sec on the position of No. 114-116 gene. [Conclusion] Sequence alignment analysis showed that the cloned gene was sus scrofa GPX2 gene ( NCBI GenBank database, the sequence number was D098982). 展开更多
关键词 Gene clone sus scrofa GPX2 RACE RT-PCR
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Analysis of Protein and Isoenzyme of LiLum davidii var.unicolor,Lilium Asiatic Hybrids and Their Hybrid F_1 被引量:1
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作者 李雪 杨彩玲 +2 位作者 张鸣 霍彩霞 朱彦荣 《Agricultural Science & Technology》 CAS 2011年第1期54-57,共4页
[Objective]The paper was to provide theoretical basis for selection of parental combination and early identification of hybrids.[Method]The soluble protein and peroxidase of LiLum davidii var.unicolor,Lilium Asiatic h... [Objective]The paper was to provide theoretical basis for selection of parental combination and early identification of hybrids.[Method]The soluble protein and peroxidase of LiLum davidii var.unicolor,Lilium Asiatic hybrids and their filial generations were analyzed using polyacrylamide gel electrophoresis technique.[Result]The protein spectrum of filial generation with L.davidii var.unicolor as parent not only appeared the homologous band as parent with darker coloring,but also had new bands compared with parent.Peroxidase zymogram of hybrid F1 mainly displayed incomplete complementary and hybrid type of parent.[Conclusion]Protein spectrum and peroxidase zymogram could be used as the biochemical markers for the identification of hybrids of lily,which could also detect the target traits of plant. 展开更多
关键词 LiLum davidii var.unicolor Lilium Asiatic hybrids Hybrid F1 PROTEIN PEROXIDASE
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Plant Traits and Soil Chemical Variables During a Secondary Vegetation Succession in Abandoned Fields on the Loess Plateau 被引量:79
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作者 王国宏 《Acta Botanica Sinica》 CSCD 2002年第8期990-998,共9页
Species dynamics in terms of both plant biological traits, ecological strategies and species richness as well as soil chemical variables during a secondary succession in abandoned fields on the Loess Plateau along a t... Species dynamics in terms of both plant biological traits, ecological strategies and species richness as well as soil chemical variables during a secondary succession in abandoned fields on the Loess Plateau along a temporal sere from 3 a to 149 a were studied. The results indicated that (I) Soil total C and N increased while soil pH, total K and Na decreased with years since abandonment. No noticeable trend was found in the case of soil P along the successional sere. On the other hand, total CaO of the surface layer (0 - 10 cm) decreased, but that of the two deeper layer, (20 - 30 cm, 40 - 50 cm) increased with years since abandonment. Soil C, N, K and P decreased, while Na, CaO and soil pH increased with increasing soil depth. (2) Species richness peaked at both mid-stage of the successional sere and the intermediate portion of soil chemical variables gradient. (3) An ideal dominant species in the early successional stage were annuals with stable seed pool, CR-life strategy, S-regeneration strategy, and strong competitive ability on relatively poor soil, while perennials capable of intensive lateral spread and colonal ability, requiring high nutrient supply, and having Clife strategy would be the dominant species in the subsequent stages. Plant traits, such as perennial-life history, C-, CR-, SC-, SR-, S- and R-life strategies, W-, S-, Bs- VBs- and V-regeneration strategies, were over- represented throughout the whole sere among the other species. (4) Some traits, such as C-, SC-life strategies, ability of clonality, perennial-life history, well-developed lateral spread ability, V- and VBs-regeneration strategies, seed animal. dispersal mode, flowering time of autumn, fruit types of legumen and nut, were more or less correlated with increased soil total C, N and K, while S-, SR-, R-, CR-life strategies, annual-, biannual-life history, non-clonal ability, S-regeneration strategy, poor lateral spread ability, and fruit types of utricle, capsule were associated with increased soil total Na, CaO and pH. The results suggested that steppes should be the dominant native vegetation coinciding with the large-scaled eco-climatic conditions on the Loess Plateau. 展开更多
关键词 abandoned fields plant trait soil chemical variable SUCCESSION Loess Plateau
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Catalytic removal of volatile organic compounds using ordered porous transition metal oxide and supported noble metal catalysts 被引量:27
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作者 刘雨溪 邓积光 +2 位作者 谢少华 王治伟 戴洪兴 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1193-1205,共13页
Most of volatile organic compounds (VOCs) are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalys... Most of volatile organic compounds (VOCs) are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalysts. Many catalysts including transition metal oxides, mixed metal oxides, and sup‐ported noble metals have been developed. Among these catalysts, the porous ones attract much attention. In this review, we focus on recent advances in the synthesis of ordered mesoporous and macroporous transition metal oxides, perovskites, and supported noble metal catalysts and their catalytic oxidation of VOCs. The porous catalysts outperformed their bulk counterparts. This excel‐lent catalytic performance was due to their high surface areas, high concentration of adsorbed oxy‐gen species, low temperature reducibility, strong interaction between noble metal and support and highly dispersed noble metal nanoparticles and unique porous structures. Catalytic oxidation of carbon monoxide over typical catalysts was also discussed. We made conclusive remarks and pro‐posed future work for the removal of VOCs. 展开更多
关键词 Volatile organic compound Catalytic combustion Porous transition metal oxide Perovskite-type oxide Supported noble metal catalyst
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Regulation of Heat Shock Factor AtHsfA1a on Ascorbate Peroxidase under Heat Stress in Arabidopsis thaliana 被引量:1
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作者 郭丽红 谭越 杨晓虹 《Agricultural Science & Technology》 CAS 2016年第8期1786-1789,共4页
[Objective] This study was conducted to investigate the regulation of heat shock factor AtHsfA1a on ascorbate peroxidase under heat stress in Arabidopsis thaliana. [Method] After heat stress treatment on transgenetic ... [Objective] This study was conducted to investigate the regulation of heat shock factor AtHsfA1a on ascorbate peroxidase under heat stress in Arabidopsis thaliana. [Method] After heat stress treatment on transgenetic A. thaliana with silenced endogenetic AtHsfA1a gene and wild A. thaliana plants as materials, the change in activity of APX enzyme was analyzed by spectrophotometry, the expression level of APX gene was investigated by real-time fluorescent quantitative PCR, and the binding condition of AtHsfAla with the promoter region of APX gene was analyzed by chromatin immunoprecipitation assay. [Result] The activity and mRNA level of APX in plants with silenced endogenetic AtHsfAla gene were higher than those in wild plants. Fragments of the promoter region of APX gene were not screened from the plants with silenced endogenetic AtHsfA1a gene, but found in wild plants. [Conclusion] This study provides a theoretical basis for the understanding of the important role of AtHsfAla in resistance to stress in plant, and is of great significance to the revealing of mechanism of resistance to stress in plant. 展开更多
关键词 Arabidopsis thaliana Heat shock factor AtHsfAla Aascorbate peroxidase Heat stress
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Effects of Excessive Mg2+ on the Germination Characteristics of Crop Seeds 被引量:23
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作者 马恩 付莎莎 张宏波 《Agricultural Science & Technology》 CAS 2008年第2期26-29,共4页
[ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,... [ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2+ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2+ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2+ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2+ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops. 展开更多
关键词 Mg^2+ stress MAIZE SOYBEAN SEEDS GERMINATION
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Two Novel Hydroperoxylated Lycopodium Alkaloids from Huperzia serrata 被引量:3
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作者 谭昌恒 马晓强 +2 位作者 周慧 蒋山好 朱大元 《Acta Botanica Sinica》 CSCD 2003年第1期118-121,共4页
Two novel hydroperoxylated Lycopodium alkaloids, 11alpha-hydroperoxyphlegmariurine B (1) and 7-hydroperoxyphlegmariurine B (2), along with a known compound, phlegmanurine B (3), were isolated from the total alkaloid f... Two novel hydroperoxylated Lycopodium alkaloids, 11alpha-hydroperoxyphlegmariurine B (1) and 7-hydroperoxyphlegmariurine B (2), along with a known compound, phlegmanurine B (3), were isolated from the total alkaloid fraction of the Chinese medicinal herb Huperzia serrata (Thunb.) Trev. Their structures and relative configurations were elucidated on the basis of spectroscopic analyses. 展开更多
关键词 Huperzia serrata Lycopodium alkaloids 11 alpha-hydroperoxyphlegmariurine B 7-hydroperoxyphlegmaniurine B
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Effects of Cu2+ and Cd2+ Stress on Growth and POD Activity of Tomato Seedling 被引量:2
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作者 赵迎春 《Agricultural Science & Technology》 CAS 2008年第2期106-108,125,共4页
The growth situation and peroxidase (POD) of seedlings of two tomato cultivars were investigated under the stress of different concentrations of Cu^2+ and Cd^2+ . The toxicity differences of Cu^2+ and Cd^2+ to t... The growth situation and peroxidase (POD) of seedlings of two tomato cultivars were investigated under the stress of different concentrations of Cu^2+ and Cd^2+ . The toxicity differences of Cu^2+ and Cd^2+ to tomato seedlings and the corresponding differences between two tomato cultivars were observed through the stress trial with the ahove two heavy metal ions, The resubs showed that low concentration of Cu^2+ and Cd^2+ could promote the growth and could enhance the POD activity of tomato seedlings, while high concentratiun Cu^2+ and Cd^2+ could inhibit seedling growth and POD activity of tomato seedlings. Cd^2+ functioned more obviously than that of Cu^2+ , two tomato cultivars also presented difference in response to heavy metal stress. 展开更多
关键词 Cu^2+ Cd^2+ Tomato seedling POD
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