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11种植物提取物对枸杞蚜虫的拒食和毒杀活性测定 被引量:22
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作者 张建英 杨贵军 +1 位作者 于有志 杨乐 《农业科学研究》 2007年第1期21-23,共3页
测定了11种植物乙醇提取物对枸杞蚜虫的拒食和毒杀活性,结果表明:苍耳、钩腺大戟、蒺藜、狼毒和伏毛铁棒锤提取液对枸杞蚜虫具有明显的拒食活性,狼毒、蒺藜和葫芦巴提取液处理枸杞蚜虫72 h,校正死亡率达90%以上,其中狼毒毒杀活性最强.
关键词 植物提取物 枸杞蚜虫 拒食 触杀
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柔性脂质体的促渗作用研究(英文) 被引量:5
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作者 胡新 刘艳 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第1期34-37,共4页
In this article different types of ultradeformable liposomes were designed and the properties of transdermal delivery were studied with sodium salicylate as model drug. These results showed that liposomes with stron... In this article different types of ultradeformable liposomes were designed and the properties of transdermal delivery were studied with sodium salicylate as model drug. These results showed that liposomes with strong hydrophilic surfactant added is a new type of penetration enhancer. 展开更多
关键词 Ultradeformable liposomes SURFACTANTS Sodium salicylate
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Single atom doping induced charge-specific distribution of Cu1-TiO_(2) for selective aniline oxidation via a new mechanism
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作者 Jiaheng Qin Wantong Zhao +6 位作者 Jie Song Nan Luo Zheng-Lan Ma Baojun Wang Jiantai Ma Riguang Zhang Yu Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期98-111,共14页
Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile... Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile,identifying the active site also represents a significant obstacle,primarily due to the intricate electronic environment of single atom site doped metal oxide.Herein,a single atom Cu doped TiO_(2)catalyst(Cu_(1)-TiO_(2)) is prepared via a simple“colloid-acid treatment”strategy,which switches aniline oxidation selectivity of TiO_(2) from azoxybenzene to nitrosobenzene,without using additives or changing solvent,while other metal or nonmetal doped TiO_(2) did not possess.Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate,two PhNOH condense to azoxybenzene over TiO_(2) catalyst.As for Cu_(1)-TiO_(2),the charge-specific distribution between the isolated Cu and TiO_(2) generates unique Cu_(1)-O-Ti hybridization structure with nine catalytic active sites,eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene.This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites. 展开更多
关键词 Single atom doped metal oxide Aniline oxidation Selectivity New mechanism Active site
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Comparative Study of the Biological Activities of the Skin Secretions from Six Common Chinese Amphibians 被引量:28
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作者 赖仞 赵宇 +3 位作者 杨东明 查宏光 李文辉 张云 《Zoological Research》 CAS CSCD 北大核心 2002年第2期113-119,共7页
Water soluble skin secretions of six common Chinese amphibians were studied for their biological and enzymatic activities.The skin secretions of Tylototriton verrucosus,Bombina maxima ,and Bufo andrewsi were f... Water soluble skin secretions of six common Chinese amphibians were studied for their biological and enzymatic activities.The skin secretions of Tylototriton verrucosus,Bombina maxima ,and Bufo andrewsi were found toxic to mice with the intraperitoneal LD 50 of 11 5?mg/kg,18 8?mg/kg,and 264?mg/kg,respectively.No acute lethal toxicities were observed for the skin secretions of Rana nigromaculata,Rana guentheri and Rana limnocharis in a dose up to 500?mg/kg.The lethal toxicities of the skin secretions of T verrucosus and B maxima to mice are in the same grade as those of Viperidae snake venoms.The toxic components in T verrucosus and B maxima skin secretions are the proteins with molecular weights ranging from 3 to 60?kDa.All the skin secretions had both proteolytic activity and trypsin inhibitory activity.The skin secretions from T verrucosus , B maxima and B andrewsi also displayed wide spectrum antimicrobial activity.On the other hand,the skin secretions from B andrewsi and B maxima showed cytotoxicity on human cancer cells.All the six samples had not significant effects on mammalian blood coagulation system.Phospholipase A 2 activity was only found in the skin secretions of T verrucosus .None of these skin secretions showed acetylcholine esterase activity. 展开更多
关键词 AMPHIBIAN TOXICITY ANTIMICROBIAL Skin secretions Biological activity
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Study on Physiological Activity of the Resistance of Medicago sativa to Thrips 被引量:4
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作者 刘玉良 米福贵 +3 位作者 特木尔布和 王普昶 马小廷 闫蓉 《Agricultural Science & Technology》 CAS 2009年第3期115-119,共5页
[Objective] The experiment explored of resistance of different Medicago sativa through synthetic variations of all physiological indexes and the correlation analysis between physiological activity and damage degree af... [Objective] The experiment explored of resistance of different Medicago sativa through synthetic variations of all physiological indexes and the correlation analysis between physiological activity and damage degree after thrips damage. [Method] According to studying physiological activity (POD activity, SOD activity, PPO activity, PAL activity, MDA content and free proline content) of alfalfa in alfalfa resistance to different number of thrips, the correlation between physiological activity and resistance was investigated. [Result] It was shown that there were negative correlations among POD, SOD, PPO, PAL, MDA, free praline and the number of thrips, and there were negative correlations among POD, SOD, PPO, PAL, MDA, free praline and CAT. The content changes of POD,SOD,PPO,CAT,MDA and free proline in high resistant alfalfa were slow and PAL was quick and the activities of PPO,PAL,CAT were high, and the activities of POD、SOD were low. [Conclusion] The research provided theoretical basis and materials for identifying resistance varieties of alfalfa to thrip. 展开更多
关键词 Medicago sativa (Alfalfa) Thrips Physiological index Correlation
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Effects of β-Amino Butyric Acid Induced Rice Blast Resistance on Reactive Oxygen Metabolism 被引量:5
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作者 李莉 郭晓丽 +5 位作者 刘晓梅 温嘉伟 张秀容 孙辉 赵宇 任金平 《Agricultural Science & Technology》 CAS 2009年第3期112-114,共3页
[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly sus... [Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly susceptible to disease as experimental material, the changes of catalase(CAT), and superoxide dismutase(SOD) and MDA activities in rice treated by BABA were investigated. [Result] In rice plants treated by BABA, the activities of CAT and SOD increased, meanwhile the MDA content also rose to some extent, resulting in the disease resistance to rice blast. [Conclusion] By influencing reactive oxygen metabolism, BABA endows rice plants with resistance to rice blast. BABA is safe to environment and has highly resistance-inducing capacity, it could be generalized in production. 展开更多
关键词 β-Amino butyric acid Rice blast Induced resistance
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Catalytic cracking of light diesel over Au/ZSM-5 catalyst for increasing propylene production 被引量:8
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作者 祁彩霞 王云霞 +1 位作者 丁孝涛 苏慧娟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1747-1755,共9页
The catalytic cracking of light diesel oil (235–337 &#176;C) over gold‐modified ZSM‐5 was investigated in a small confined fluidized bed at 460 &#176;C and ambient pressure. Different Au/ZSM‐5 catalysts were p... The catalytic cracking of light diesel oil (235–337 &#176;C) over gold‐modified ZSM‐5 was investigated in a small confined fluidized bed at 460 &#176;C and ambient pressure. Different Au/ZSM‐5 catalysts were prepared by a modified deposition‐precipitation method by changing the preparation procedure and the amount of gold loading and were characterized by X‐ray diffraction, N2 adsorp‐tion‐desorption, temperature‐programmed desorption of NH3, transmission electron microscopy and inductively coupled plasma spectrometer. It was found that a small amount of gold had a posi‐tive effect on the catalytic cracking of light diesel oil and increased propylene production at a rela‐tively low temperature. The maintenance of the ZSM‐5 MFI structure, pore size distribution and the density of weak and strong acid sites of the Au/ZSM‐5 catalysts depended on the preparation pa‐rameters and the Au loading. Simultaneous enhancement of the micro‐activity and propylene pro‐duction relies on a synergy between the pore size distribution and the relative intensity of the weak and strong acid sites. A significant improvement in the micro‐activity index with an increase of 4.5 units and in the propylene selectivity with an increase of 23.2 units was obtained over the Au/ZSM‐5 catalyst with an actual Au loading of 0.17 wt%. 展开更多
关键词 Fluid catalytic cracking Gold modification Propylene selectivity Micro-activity test
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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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Study on Damage Characteristics of Weedy Rice 被引量:1
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作者 郭勋斌 季宏癉 +3 位作者 冯长云 陈伟民 顾克礼 袁秦 《Agricultural Science & Technology》 CAS 2015年第4期789-792,共4页
In this study, several typical tralts of weedy rice and its damage charac-teristics were analyzed. The resuIts showed that the shattering of weedy rice was sometimes weaker than that of conventional rice. The newIy-ha... In this study, several typical tralts of weedy rice and its damage charac-teristics were analyzed. The resuIts showed that the shattering of weedy rice was sometimes weaker than that of conventional rice. The newIy-harvested weedy rice seeds have certaln dormant period and a Iong active period, whiIe the conventional rice seeds have no dormant period but have a Iimited active period. In the direct seeding and intercropping rice fields where weedy rice occurs seriousIy Iast year, if not controI ed timeIy, weedy rice may caused a damage above 28%, sometimes even above 99%. After one season of cuItivation, the underground weedy rice and conventional rice seeds wiI be carbonized, Iosing their activity. The germination of underground weedy rice can be first induced, and when the Iast-season wheat is harvested, the germinated weedy rice can be kiI ed with 41% gIyphosate (3 000 mI/hm2), thus the damage and expansion of weedy rice wiI be effectiveIy controI ed. 展开更多
关键词 Weedy rice SHATTERING Seed activity DAMAGE CHARACTERISTICS
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A Bioactive Diterpene from the Chinese Herb Aster souliei 被引量:2
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作者 张永红 王燕玲 +2 位作者 蔡爱华 王勤 程东亮 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第4期285-287,共3页
Aster souliei Franch, (Compositae) is a. herbaceous plant distributed innorth China. It has been used in folk medicine as antipyretic, detoxicant, expectorant andantitussive. In an effort to find biologically active c... Aster souliei Franch, (Compositae) is a. herbaceous plant distributed innorth China. It has been used in folk medicine as antipyretic, detoxicant, expectorant andantitussive. In an effort to find biologically active components from Chinese medicinal plants ' ,we have examined the aerial parts of this herb, leading to the isolation of a clerodane-typediterpene, 18, 19-dihydroxy-5α, 10β-neo-cleroda-3, 13 (l4)-dien-16, 15-butenolide (1). In thispaper we report the structural elucidation, and the antitumor and antibacterial activities of thiscompound. It was found that 1 possesses moderate cytotoxicity against human leukemia cells (HL-60)and activity against microorganisms. 展开更多
关键词 aster souliei COMPOSITAE DITERPENE CYTOTOXICITY antibacterial activity
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Density functional theory study of influence of impurity on electronic properties and reactivity of pyrite 被引量:8
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作者 李玉琼 陈建华 +1 位作者 陈晔 郭进 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1887-1895,共9页
The electronic property of pyrite supercell containing As,Se,Te,Co or Ni hetero atoms were calculated using density functional theory(DFT),and the reactivities of pyrite with oxygen and xanthate were discussed by fr... The electronic property of pyrite supercell containing As,Se,Te,Co or Ni hetero atoms were calculated using density functional theory(DFT),and the reactivities of pyrite with oxygen and xanthate were discussed by frontier orbital methods.The cell volume expands due to the presence of impurity.Co and Ni mainly affect the bands near Fermi levels,while As mainly affects the shallow and deep valence bands,and Se and Te mainly affect the deep valence bands.Electronic density analysis suggests that there exists a strong covalent interaction between hetero atom and its surrounding atoms.By frontier orbital calculation,it is suggested that As,Co and Ni have greater influence on the HOMO and LUMO of pyrite than Se and Te.In addition,pyrite containing As,Co or Ni is easier to oxidize by oxygen than pyrite containing Se or Te,and pyrite containing Co or Ni has greater interaction with collector.These are in agreement with the observed pyrite practice. 展开更多
关键词 PYRITE IMPURITY density functional theory electronic properties REACTIVITY
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Screening of a Novel Bioflocculant-producing Strain and Research on Its Flocculation 被引量:4
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作者 周爱华 梁生康 单宝田 《Agricultural Science & Technology》 CAS 2012年第9期1997-2000,2005,共5页
[Objective] This study aimed to screen a bacterial strain capable of producing bioflocculant. [Method] A bacterial strain T-11 capable of producing bioflocculant was isolated from activated sludge. Detailed tests on t... [Objective] This study aimed to screen a bacterial strain capable of producing bioflocculant. [Method] A bacterial strain T-11 capable of producing bioflocculant was isolated from activated sludge. Detailed tests on the morphological, physiological and biochemical characteristics were carried out and identification was performed to identify the strain. Finally, the bioflocculant was isolated and purified, and the flocculating activity and chemical characteristics were measured. [Result] It was identified as Serratia plumuthica based on its morphological, physiological and biochemical characteristics. This strain secreted flocculant best in a culture medium which included sucrose and NaNO3. The maximal cell growth was achieved within 10 h and the flocculating activity paralleled to it. It was found to be effective for flocculation of kaolin suspension, when added at a final concentration of 0.7 mg/L, over a range of pHs (2-7), and temperature (approximately 30-80 ℃). Chemical analysis indicated that the bioflocculant was an acidic polysaccharide consisting of glucose, glucuronic acid and galactose, talose and altrose. Infrared spectrum analysis also revealed typical characteristics of polysaccharides. [Conclusion] The biofloccu- lants produced by strain T-11 can greatly improve the ability of activated sludge to settle. 展开更多
关键词 BIOFLOCCULANT Flocculating activity POLYSACCHARIDE Serratia plumuthica
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Facile preparation of nanocrystal-assembled hierarchical mordenite zeolites with remarkable catalytic performance 被引量:9
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作者 袁扬扬 王林英 +4 位作者 刘红超 田鹏 杨淼 徐舒涛 刘中民 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1910-1919,共10页
The present study reports a novel strategy to fabricate nanocrystal-assembled hierarchical MOR zeolites. This is the first demonstration of hierarchical MOR without preferential growth along the c-axis, which facilita... The present study reports a novel strategy to fabricate nanocrystal-assembled hierarchical MOR zeolites. This is the first demonstration of hierarchical MOR without preferential growth along the c-axis, which facilitates mass transfer in the 12-membered ring channels of MOR zeolite for the conversions involving bulky molecules. The facile method involves the combined use of tetraethylammonium hydroxide (TEAOH) and commercial surfactants, in which TEAOH is essential for the construction of nanocrystal assemblies. The surfactant serves as a crystal growth-inhibiting agent to further inhibit nanocrystalline particle growth, resulting in enhanced mesoporosity. The hierarchical MOR assembled particles, constructed of 20-50-nm crystallites, exhibit superior catalytic properties in the alkylation of benzene with benzyl alcohol compared with the control sample, as the hierarchical MOR possesses a larger external surface area and longer c-axis dimension. More importantly, the material shows improved activity and stability in the dimethyl ether carbonylation to methyl acetate reaction, which is a novel route to produce ethanol from syngas. 展开更多
关键词 Nanocrystal-assembled Mordenite Tetraethylammonium hydroxide Surfactant Catalytic activity
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Phosphorus Starvation-induced Expression of Leaf Acid Phosphatase Isoforms in Soybean 被引量:10
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作者 田江 廖红 +1 位作者 王秀荣 严小龙 《Acta Botanica Sinica》 CSCD 2003年第9期1037-1042,共6页
Leaf acid phosphatase (APase) activities of 274 soybean genotypes were surveyed under field conditions with two levels of P supplies, and a nutrient solution culture experiment with eight selected genotypes was subseq... Leaf acid phosphatase (APase) activities of 274 soybean genotypes were surveyed under field conditions with two levels of P supplies, and a nutrient solution culture experiment with eight selected genotypes was subsequently conducted under greenhouse conditions to further characterize APase activity and its isoform expression induced by P starvation. Results from the field experiment showed that there was a great genotypic variation for leaf APase activity among the tested soybean genotypes from different origins, and APase activity in many of the tested genotypes (about 60%) was generally increased in the treatment without P fertilizer addition. Results from the nutrient solution culture experiment showed that APase activity in all the eight tested genotypes was generally enhanced by P starvation. Six isoforms of APases were detected in isoelectric focusing gels with samples from both young and old leaves. The activity of all the six isoforms was increased by P starvation, but no new APase isoform was induced. Our results suggest that leaf APase activity could serve as an enzymatic indicator of P starvation for soybean; the increase in leaf APase activity under low P stress was mainly caused by the increase in the activity of existing isoforms but not by the induction of new isoforms. 展开更多
关键词 acid phosphatase activity phosphorus starvation isoelectric focusing gel acid phosphatase isoform SOYBEAN
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Novel Stilbene Glycosides from Polygonum multiflorum 被引量:11
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作者 肖凯 宣利江 +1 位作者 徐亚明 白东鲁 《Acta Botanica Sinica》 CSCD 2002年第12期1491-1494,共4页
Two new stilbene glycosides (1 and 2), together with nine known compounds (3-11), were isolated from the water extract of Polygonum multiflorum Thunb. The structures of the new compounds were elucidated by their c... Two new stilbene glycosides (1 and 2), together with nine known compounds (3-11), were isolated from the water extract of Polygonum multiflorum Thunb. The structures of the new compounds were elucidated by their chemical properties and spectroscopic analyses, including extensive 2D NMR experiments. Compound 2 showed strong DNA cleavage activity, and compounds 1, 2 and 10 (2, 3, 4′, 5_tetrahydroxy_ trans _stilbene_2_O_β_ D _glucopyranoside) exhibited significant inhibition of lipid peroxidation. 展开更多
关键词 Polygonum multiflorum stilbene glycoside DNA cleavage activity inhibition of lipid peroxidation
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Influence of Ga and In on microstructure and electrochemical properties of Mg anodes 被引量:4
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作者 冯艳 王日初 彭超群 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2650-2656,共7页
The influence of Ga and In on the electrochemical properties of Mg anode materials were investigated by the polarization and galvanostatic curve tests. The microstructure and the corroded surface of the Mg-In-Ga alloy... The influence of Ga and In on the electrochemical properties of Mg anode materials were investigated by the polarization and galvanostatic curve tests. The microstructure and the corroded surface of the Mg-In-Ga alloys were observed by scanning electron microscopy (SEM). The corrosion product of the Mg-0.8%In (mass fraction) and Mg-0.8%Ga-0.3%In alloy were determined by X-ray diffraction. The results show that no second phase exists in the Mg-xIn (x=0-0.8%) allloys. Intergranular compounds containing Ga and In elements occur in the Mg-0.8%In-xGa (x=0-0.8%) alloys. The addition of In into Mg as well as the addition of 0.05%-0.5%Ga into Mg-In alloy promotes the corrosion resistance. The addition of Ga into Mg-In alloys also promotes the electrochemical activity. The Mg-0.8%In-0.8%Ga alloy has the most negative mean potential,-1.682 V, which is more negative than -1.406 V in AZ91D. The corrosion type of the Mg-In-Ga alloys is general corrosion and the corrosion product is Mg(OH)2. 展开更多
关键词 Mg anode alloying element GA In galvanostatic curve corrosion resistance electrochemical activity
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Physicochemical Characters of rPoIFN-α and Its Antiviral Activity in vitro 被引量:3
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作者 汤仁树 赵俊 王明丽 《Agricultural Science & Technology》 CAS 2010年第1期65-68,共4页
[Objective]The research aimed to test and identify the physicochemical characters and antiviral activity in vitro of semi-finished product of the recombinant porcine rPoIFN-α. [Method]HEp-2/VSV system was used to tes... [Objective]The research aimed to test and identify the physicochemical characters and antiviral activity in vitro of semi-finished product of the recombinant porcine rPoIFN-α. [Method]HEp-2/VSV system was used to test the antiviral activity of three batches of rPoIFN-α. Using recombinant human IFN-α as reference,the titer of interferon was measured. The semi-finished product of rPoIFN-α with the known titer were treated with 0.25% trypsin,HCl and mouse anti-porcine IFN-α monoclonal antibody. And the anti-viral activity of each batch of rPoIFN-α was detected. The physicochemical characters of rPoIFN-α were evaluated. The inhibition of induced cytopathic effect of rPoIFN-α on PPV (Porcine parvovirus) and PRV (Porcine pseudorabies) on swine kidney cell (PK-15) was determined. And the antiviral activity of rPoIFN-α in vitro was observed. [Result]The titers of semi-finished products of rPoIFN-α titrated by HEp-2/VSV system could reach 1.5×105 IU/ml,with the specific activity of 1.1×106 IU/mg. The residual rate of the tier of rPoIFN-α treated by 0.25% trypsin at 37 ℃ for 1 h was less than 1%. And that treated with HCl (pH of 2.0) for 72 h was up to 95%. And that treated at 56 ℃ for 30 min and that treated by mouse anti-porcine IFN-α monoclonal antibody at 37 ℃ for 1 h were higher than 47% and about 1% respectively. The antiviral test in vitro showed that 50 and 500 IU/ml rPoIFN-α could inhibit the induced cytopathic effect of PRV and PPV on PK-15 cell lines. [Conclusion]rPoIFN-α had the basic physicochemical characters of IFN-α. And it could inhibit the induced cytopathic effect of PRV and PPV on PK-15 cell lines,but there was dosage difference. 展开更多
关键词 Porcine interferon α Physicochemical character Antiviral activity
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Photocatalytic activity and kinetics for acid yellow degradation over surface composites of TiO_2-coated activated carbon under different photocatalytic conditions 被引量:3
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作者 曾孟雄 李佑稷 +2 位作者 马明远 陈伟 李雷勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1019-1027,共9页
TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to es... TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate. 展开更多
关键词 PHOTOCATALYSIS TiO2-coated activated carbon acid yellow composite catalyst
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Study on Kinetic Characteristics of Alliinase 被引量:4
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作者 葛艳辉 赵俊英 +1 位作者 闵笛 冯炘 《Agricultural Science & Technology》 CAS 2008年第1期139-142,共4页
[Objective] The kinetic characteristics of alliinase was studied to select the optimum reaction performance. [Method] Alliinase activity was measured to analysis the influence of temperature, pH, substrate concentrati... [Objective] The kinetic characteristics of alliinase was studied to select the optimum reaction performance. [Method] Alliinase activity was measured to analysis the influence of temperature, pH, substrate concentration and metal iron. [Result] Alliinase was an enzyme with thermal instability. Its optimum reaction temperature was 29℃ and pH value was 6.1. The Vmax was 0. 439 IU/mg and Km was 0.483 mmol/L by using natural extract as substrate. Alliinase activity was activated when the K^+ , Mg^2+ , Na^+ and Cd^2+ existed and alliinase activity was inhibited when Cu^2+ existed. [Condusion] Results showed that the kinetic characteristics of alliinase supply the academic foundation for development and application of garlic medical products. 展开更多
关键词 Allium sativum ALLIINASE Kinetic characteristics
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Synthesis, Surface Activity, and Antifogging Property of Triethanolamine Monolaurate Ester 被引量:2
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作者 蔡梦军 李青青 陈雪梅 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期223-229,I0002,共8页
Triethanolamine monolaurate ester was synthesized by lauric acid and triethanolamine (TEA) with a molar ratio around 1:1 and the esterification process was investigated and optimized. The esterification product of ... Triethanolamine monolaurate ester was synthesized by lauric acid and triethanolamine (TEA) with a molar ratio around 1:1 and the esterification process was investigated and optimized. The esterification product of lauric acid with TEA was characterized by infrared spectra and nuclear magnetic resonance. The surface tension (TCMC) at the critical micelle concentration (CMC) was determined, and the antifogging properties of triethanolamine laurate ester on low-density polyethylene (LDPE) films were also measured. The results indicated that the yield of triethanolamine monolaurate ester was more than 69% under optimized esterification condition, the CMC value and 7CMC of esterification product was 0.91 p.g/mL and 22.1 mN/m in aqueous solution at 25 ℃, respectively. The first-drop time and ten-drop time was 257 and 86 s, respectively, and the antifogging duration of triethanolamine laurate ester on the surface of LDPE film at 60 ℃ was more than 150 h. 展开更多
关键词 TRIETHANOLAMINE LAURATE SURFACTANT Antifogging property
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