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Expression Detection of DMRTs and Two sox9 Genes in Takifugu rubripes (Tetraodontidae, Vertebrata) 被引量:15
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作者 SHEN Xueyan CUI Jianzhou YANG Guanpin GONG Qingli GU qianqun 《Journal of Ocean University of China》 SCIE CAS 2007年第2期182-186,共5页
Sex determination and sex differentiation are important phenomena in fish, but the mechanisms of sex determination in Takifugu rubripes are poorly understood. In our study, the expression patterns of genes for DMRTs ... Sex determination and sex differentiation are important phenomena in fish, but the mechanisms of sex determination in Takifugu rubripes are poorly understood. In our study, the expression patterns of genes for DMRTs (DMRT1, DMRT2 and DMRT3),sox9a and sox9b in T. rubripes tissues were verified with the Reverse Transcription (RT)-PCR detection. It is showed that DMRT1 expressions in testis and ovaries were much lower, and no expressions were fotmd in muscle, blood and tailfin. However, expressions for DMRT2 and DMRT3 were not found in the tissues stated above. Transcripts of sox9a were detected in muscle, fin, ovary and testis, but not in blood, whereas sox9b expression was only detected in ovary. The expression patterns of DMRTs, sox9a and sox9b in T. rubripes gonads suggest that these genes may not be sex-specific. 展开更多
关键词 DMRTs RT-PCR sex determination SOX9 Talafugu rubripes gene expression OVARY
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A Polysaccharide-Degrading Marine Bacterium Flammeovirga sp.MY04 and Its Extracellular Agarase System 被引量:5
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作者 HAN Wenjun GU Jingyan +4 位作者 YAN Qiujie LI Jungang WU Zhihong GU qianqun LI Yuezhong 《Journal of Ocean University of China》 SCIE CAS 2012年第3期375-382,共8页
Bacteria of the genus Flammeovirga can digest complex polysaccharides (CPs), but no details have been reported regarding the CP depolymerases of these bacteria. MY04, an agarolytic marine bacterium isolated from coast... Bacteria of the genus Flammeovirga can digest complex polysaccharides (CPs), but no details have been reported regarding the CP depolymerases of these bacteria. MY04, an agarolytic marine bacterium isolated from coastal sediments, has been identified as a new member of the genus Flammeovirga. The MY04 strain is able to utilize multiple CPs as a sole carbon source and grows well on agarose, mannan, or xylan. This strain produces high concentrations of extracellular proteins (490 mg L-1 ± 18.2 mg L-1 liquid culture) that exhibit efficient and extensive degradation activities on various polysaccharides, especially agarose. These proteins have an activity of 310 U mg-1 ± 9.6 U mg-1 proteins. The extracellular agarase system (EAS) in the crude extracellular enzymes contains at least four agarose depolymerases, which are with molecular masses of approximately 30-70 kDa. The EAS is stable at a wide range of pH values (6.0-11.0), temperatures (0-50℃), and sodium chloride (NaCl) concentrations (0- 0.9 mol L-1). Two major degradation products generated from agarose by the EAS are identified to be neoagarotetraose and neoagarohexaose, suggesting that β-agarases are the major constituents of the MY04 EAS. These results suggest that the Flammeovirga strain MY04 and its polysac-charide-degradation system hold great promise in industrial applications. 展开更多
关键词 Flammeovirga polysaccharide degradation extracellular agarase system neoagaro-oligosaccharide
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The Cytotoxic Constituents from Marine-derived Streptomyces 3320^(#) 被引量:4
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作者 REN Hong GU qianqun +1 位作者 CUI Chengbin ZHU Weiming 《Journal of Ocean University of China》 SCIE CAS 2006年第1期75-81,共7页
The present work studies the chemical constituents from marine-derived streptomyces 3320^# and their antitumor activities. The n-BuOH extract of the ferment broth of 3320^# was chromatographed on silica gel, Sephadex ... The present work studies the chemical constituents from marine-derived streptomyces 3320^# and their antitumor activities. The n-BuOH extract of the ferment broth of 3320^# was chromatographed on silica gel, Sephadex LH-20, ODS columns and HPLC to separate the compounds with antitoumor activities. Their structures were identified using IR, UV, NMR, MS spectroscopic techniques and compared with published data. The antitumor activities of the isolates were assayed using SRB method and flow cytometry assay, accompanied with the morphological observation of the cells under light micro- scope against mammalian tsFT210 cells. Ten compounds, cyclo-(Ala-Leu) 1, cyclo-(Ala-Ile) 2, cyclo-(Ala-Val) 3, cyclo- (Phe-Pro) 4, cyclo-(Phe-Gly)5, cyclo-(Leu-Pro)6, 1-methyl-1, 2, 3, 4-tetrahydro-β-carboline-3-carboxylic acid 7, N-(4- hydroxyphenethyl) acetamide 8, 4-methyoxy-l-(2-hydroxy) ethylbenzene 9 and uridine 10, were isolated from the ferment broth of streptomyces 3320^# . Among them, compounds 6, 7, 8 and 10 showed potent cytotoxicity against the tsFT210 cell with the IC50 values of 3.6, 7.2, 5.2 and 1.6 mmol L-1, respectively. Compounds 8, 10 also exhibited apoptosis inducing activity under 2.0 mmol L-1. Compounds 6, 7, 8 and 10 are the principle bioactive constituents responsible for the antitumor activities of marine streptomyces 3320^#. Compound 7 was isolated from this species for the first time. 展开更多
关键词 marine-derived streptomyces secondary metabolites structural identify bioassay-guided fractionation antitumor activity
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The Antitumor Components from Marine-derived Bacterium Streptoverticillium luteoverticillatum 11014 Ⅱ 被引量:4
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作者 LI Dehai ZHU Tianjiao FANG Yuchun LIU Hongbing GU qianqun ZHU Weiming 《Journal of Ocean University of China》 SCIE CAS 2007年第2期193-195,共3页
Eight known compounds were isolated from a marine-derived bacterium Streptoverticillium luteoverticillatum 11014 using bioassay-guided fractionations. Their structures were identified by spectral analysis as bis (4-h... Eight known compounds were isolated from a marine-derived bacterium Streptoverticillium luteoverticillatum 11014 using bioassay-guided fractionations. Their structures were identified by spectral analysis as bis (4-hydroxybenzyl) ether (1), p-hydroxyphenylethyl alcohol (2), N-(4-hydroxyphenethyl) acetamide (3), indole-3 carboxylic acid methyl ester (4), dibenzo[b,e] [1,4]dioxine (5), thymine (6), cytosine deoxyribonucleoside (7) and 2, 3-butanediol (8). These compounds were evaluated for their cytotoxic activities against K562 cell line with the SRB method for the first time. Compounds 2 and 4 showed cytotoxcities with IC50 values of 101.1 and 165.3 μolL^-1, respectively. All compounds were isolated from S. luteoverticillatum 11014 for the first time. 展开更多
关键词 marine-derived bacterium Streptoverticillium luteoverticillatum antitumor activity
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Secondary Metabolites of a Deep Sea Derived Fungus Aspergillus versicolor CXCTD-06-6a and Their Bioactivity 被引量:3
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作者 KONG Xianglan CAI Shengxin +3 位作者 ZHU Tianjiao GU qianqun LI Dehai LUAN Yepeng 《Journal of Ocean University of China》 SCIE CAS 2014年第4期691-695,共5页
In order to obtain novel secondary metabolites, a deep sea inhabiting fungus Aspergillus versicolor CXCTD-06-6a was investigated. One new diketopiperazine brevianamide W(1a), as well as five known diketopiperazine alk... In order to obtain novel secondary metabolites, a deep sea inhabiting fungus Aspergillus versicolor CXCTD-06-6a was investigated. One new diketopiperazine brevianamide W(1a), as well as five known diketopiperazine alkaloids, diketopiperazine V(1b), brevianamide Q(2), brevianamide R(3), brevianamide K(4), and brevianamide E(5), were isolated from the Et OAc extract of the fermentation broth. Their structures were elucidated by spectroscopy techniques(NMR, MS). The six compounds exhibited moderate radical scavenging activity against DPPH with clearance ratio of 55.0%(1a and 1b), 53.7%(2), 46.2%(3), 61.4%(4) and 19.3%(5) at a concentration of 13.9 μmol L-1, respectively; while the positive control ascorbic acid showed a ratio of 70.3% at the concentration of 28.4 μmol L-1. 展开更多
关键词 deep sea fungus secondary metabolite DIKETOPIPERAZINE
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Construction of a Metagenomic DNA Library of Sponge Symbionts and Screening of Antibacterial Metabolites 被引量:3
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作者 CHEN Juan ZHU Tianjiao +6 位作者 LI Dehai CUI Chengbin FANG Yuchun LIU Hongbing LIU Peipei GU qianqun ZHU Weiming 《Journal of Ocean University of China》 SCIE CAS 2006年第2期119-122,共4页
To study the bioactive metabolites produced by sponge-derived uncultured symbionts, a metagenomic DNA library of the symbionts of sponge Gelliodes gracilis was constructed. The average size of DNA inserts in the libra... To study the bioactive metabolites produced by sponge-derived uncultured symbionts, a metagenomic DNA library of the symbionts of sponge Gelliodes gracilis was constructed. The average size of DNA inserts in the library was 20 kb. This library was screened for antibiotic activity using paper disc assaying. Two clones displayed the antibacterial activity against Micrococcus tetragenus. The metabolites of these two clones were analyzed through HPLC. The result showed that their metabolites were quite different from those of the host E. coli DNA and the host containing vector pHZ132. This study may present a new approach to exploring bioactive metabolites of sponge symbionts. 展开更多
关键词 metagenomic DNA library SPONGE SYMBIONTS METABOLITE bioactivity
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Structures and Antiviral Activities of Butyrolactone Derivatives Isolated from Aspergillus terreus MXH-23 被引量:2
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作者 MA Xinhua ZHU Tianjiao +3 位作者 GU qianqun XI Rui WANG Wei LI Dehai 《Journal of Ocean University of China》 SCIE CAS 2014年第6期1067-1070,共4页
A new butyrolactone derivative,namely butyrolactone Ⅷ (1),and six known butyrolactones (2-7) were separated from the ethyl acetate (EtOAc) extract of the fermentation broth of a fungus,Aspergillus terreus MXH-2... A new butyrolactone derivative,namely butyrolactone Ⅷ (1),and six known butyrolactones (2-7) were separated from the ethyl acetate (EtOAc) extract of the fermentation broth of a fungus,Aspergillus terreus MXH-23.The chemical structures of these metabolites were identified by analyzing their nuclear magnetic resonance (NMR) and mass spectrometry (MS).Known butyrolactone derivatives contain an α,β-unsaturated γ-lactone ring with α-hydroxyl and y-benzyl,and butyrolactone Ⅷ (1) was the first butyrolactones contains α-benzyl and γ-hydroxyl on α,β-unsaturated lactone ring.All of the butyrolactone derivatives were tested for their anti-influenza (H 1N 1) effects.Derivatives 4 and 7 showed moderate antiviral activities while the newly-identified,derivative 1,did not. 展开更多
关键词 sponge-derived fungus secondary metabolite butyrolactone anti-influenza activity
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Linear polyketides produced by co-culture of Penicillium crustosum and Penicillium fellutanum 被引量:1
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作者 Guihong Yu Peng Sun +8 位作者 Reyilamu Aierken Chunxiao Sun Zhenzhen Zhang Qian Che Guojian Zhang Tianjiao Zhu qianqun Gu Mingyu Li Dehai Li 《Marine Life Science & Technology》 SCIE CAS 2022年第2期237-244,共8页
Two new polyketides, penifellutins A (1) and B (2), possessing a 22 carbon linear skeleton, were isolated from a co-culture of the deep-sea-derived fungi Penicillium crustosum PRB-2 and Penicillium fellutanum HDN14-32... Two new polyketides, penifellutins A (1) and B (2), possessing a 22 carbon linear skeleton, were isolated from a co-culture of the deep-sea-derived fungi Penicillium crustosum PRB-2 and Penicillium fellutanum HDN14-323. Meanwhile, two esterification products of 1, penifellutins C (3) and D (4), were obtained because compound 1 could be esterified spontaneously when stored in methanol. Their configurations were difficult to determine because of chiral central crowdedness, structural flexibility and instability. As such, we solved this issue by comprehensively using Mo2(OAc)4-based CD experiments, density functional theory calculation of 13C NMR, DP4 + probability analysis and many chemical reactions, including making acetonide derivative, Mosher’s method, PGME method, etc. Compounds 1 and 2 show obvious inhibitory activity on the liver hyperplasia of zebrafish larvae at a concentration of 10 μmol/L, while 3 and 4 show no activity, indicating that two carboxyls in the structure are important active sites. 展开更多
关键词 CO-CULTURE POLYKETIDES Extraction and isolation Structure elucidation ANTIPROLIFERATION
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Effect of diluents on the extraction of uranium (VI) with N-oetanoyl-2-methylpiperidine
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作者 XIANGQun BAOBo-Rong +1 位作者 qianqun SHAOHua 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第3期168-170,共3页
The extraction of uranium ((Ⅵ) from nitric acid solution with N-octanoyl-2-methylpiperidine (OMPPD)in eight diluents and the dependence of distribution ratio on temperature and concentrations of both aqueous nitricac... The extraction of uranium ((Ⅵ) from nitric acid solution with N-octanoyl-2-methylpiperidine (OMPPD)in eight diluents and the dependence of distribution ratio on temperature and concentrations of both aqueous nitricacid and OMPPD were investigated. The interaction among OMPPD, the extracted species and diluent has been dis-cussed. The experiments show that the extraction ability of OMPPD decreases gradually for eight diluents in the fol-lowing order: benzene, toluene, n-octane, sulfonated kerosene, cyclohexane, carbon tetrachloride, 1,2-dichloroetheneand chloroform. It cannot be interpreted only on the basis of polarity of diluents. 展开更多
关键词 辛酰基 萃取工艺 硝酸 OMPPD
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Strain and Culture Medium Optimization for Production Enhancement of Prodiginines from Marine-Derived Streptomyces sp. GQQ-10
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作者 LI Xueping ZHANG Guojian +2 位作者 ZHU Tianjiao LI Dehai GU qianqun 《Journal of Ocean University of China》 SCIE CAS 2012年第3期361-365,共5页
A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employe... A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employed for medium optimization. In the single factor method, the effects of soluble starch, glucose, soybean flour, yeast extract and sodium acetate on PGs production were investigated individually. In the subsequent OAD experiments, the concentrations of these 5 key nutritional components combined with salinity were further adjusted. The mutant strain GQQ-M6 gave a 2.2-fold higher PGs production than that of the parent strain; OAD experiments offered a PGs yield of 61mg L-1, which was 10 times higher than that of the initial GQQ-10 strain under the original cultivation mode. 展开更多
关键词 prodiginines marine-derived streptomycete optimization culture media mutation
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水库坝基防渗技术与稳定性分析 被引量:1
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作者 马谦群 《云南水力发电》 2024年第3期67-69,81,共4页
在新建或扩建水库工程时,为确保水库质量满足要求,使其能够正常运行,坝基防渗的研究意义重大。以深圳市清林径水库坝基防渗工程为背景,针对目前面对的工程现状和工程地质条件,提出了坝基防渗设计方案和施工质量控制要点,采用的帷幕灌浆... 在新建或扩建水库工程时,为确保水库质量满足要求,使其能够正常运行,坝基防渗的研究意义重大。以深圳市清林径水库坝基防渗工程为背景,针对目前面对的工程现状和工程地质条件,提出了坝基防渗设计方案和施工质量控制要点,采用的帷幕灌浆结合混凝土墙在水库坝基防渗应用效果好,确保新建水库防渗性能满足生产生活的需要,增加深圳市储备应急库容,提高深圳市供水安全保障的需要。 展开更多
关键词 水库坝基 防渗技术 帷幕灌浆 稳定性分析
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云南南涧首次发现独立钴矿床
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作者 程迁群 梁元钊 +6 位作者 刘明勇 雷阳艾 谢行 朱振东 李书程 豆松 郑晓军 《矿产勘查》 2024年第5期906-908,共3页
钴(Co)是全球关键矿产,也是中国紧缺战略性矿产,随着新能源产业的快速发展,其重要性日益凸显,成为全球勘查开发和投资并购的热点。钴广泛应用于新能源汽车、军事、航空、化工和医疗等领域,目前最主要的用途是锂离子电池的正极材料和制... 钴(Co)是全球关键矿产,也是中国紧缺战略性矿产,随着新能源产业的快速发展,其重要性日益凸显,成为全球勘查开发和投资并购的热点。钴广泛应用于新能源汽车、军事、航空、化工和医疗等领域,目前最主要的用途是锂离子电池的正极材料和制造航天发动机所需的高温合金。 展开更多
关键词 投资并购 新能源汽车 新能源产业 航天发动机 锂离子电池 勘查开发 高温合金 钴矿床
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CNTs增强Sn-Bi基复合钎料回流焊焊点显微组织及力学性能
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作者 黄清 彭倩群 +1 位作者 张文妍 毛育青 《精密成形工程》 北大核心 2024年第11期160-167,共8页
目的为了解决Sn-Bi焊点难以满足高密度封装结构长期服役可靠性要求的难题,研制了CNTs增强Sn-Bi基复合钎料,并分析了复合钎料对焊点组织与力学性能的影响。方法采用机械混合方式制备了不同碳纳米管(CNTs)含量(0%、0.01%、0.025%、0.1%、0... 目的为了解决Sn-Bi焊点难以满足高密度封装结构长期服役可靠性要求的难题,研制了CNTs增强Sn-Bi基复合钎料,并分析了复合钎料对焊点组织与力学性能的影响。方法采用机械混合方式制备了不同碳纳米管(CNTs)含量(0%、0.01%、0.025%、0.1%、0.25%,质量分数)的Sn-58Bi基复合钎料,随后采用回流焊方法对Cu薄板进行搭接焊。通过SEM、EDS等技术分析了焊点内的显微组织及界面金属间化合物(Inermetallic Compound,IMC)变化,并使用拉力测试仪研究了焊点剪切强度的变化规律。结果Cu/Sn-58Bi/Cu焊点的显微组织主要为黑色树枝状富Sn相和灰白色层片状富Bi的共晶组织,界面处IMC成分为扇贝状的Cu_(6)Sn_(5)相。添加CNTs可以明显细化组织晶粒,当CNTs质量分数为0.025%时,组织细化最明显。在Sn-58Bi钎料中添加一定量的CNTs可以明显提高焊点的剪切性能,当CNTs质量分数为0.025%时,焊点剪切性能最优,其剪切强度为27.5MPa,相较于Sn-58Bi/Cu焊点,提高了43.37%。结论在一定范围内,随着CNTs含量的增加,Sn-Bi-CNTs复合钎料焊点的显微组织得到明显细化,焊点拉剪性能显著提高。 展开更多
关键词 碳纳米管 Sn-Bi钎料 回流焊焊点 微观组织 拉剪性能
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云南个旧锡铜多金属矿集区找矿方向及靶区优选 被引量:2
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作者 罗太旭 王宗元 +4 位作者 黄合祥 肖述刚 孙聪伍 程迁群 余莉 《矿产与地质》 2021年第5期823-831,848,共10页
在前期研究成果的基础上,进一步总结个旧矿区成矿地质条件、成矿规律、控矿模式等,通过对矿区成矿环境、成矿时期、成矿顺序的再认识,借鉴近年来在矿区找矿工作中获得的成功经验,结合矿区现状和实际,提出个旧矿区新一轮找矿方向和思路:... 在前期研究成果的基础上,进一步总结个旧矿区成矿地质条件、成矿规律、控矿模式等,通过对矿区成矿环境、成矿时期、成矿顺序的再认识,借鉴近年来在矿区找矿工作中获得的成功经验,结合矿区现状和实际,提出个旧矿区新一轮找矿方向和思路:一是东区以马拉格矿田以南的芦塘坝—麒麟山地区、老厂东凹、风流山地区、仙人洞—龙树脚地区为四大重点目标区域;二是西区以张保寨—梨花寨、八里寨—头道水村一带、陡岩锡矿外围及深部作为重点找矿突破目标区域,采取地质、物探、化探相结合方式,以已知矿床、矿点为中心,逐步向外围或深部寻求找矿突破。 展开更多
关键词 锡铜多金属矿 找矿方向 靶区优选 云南个旧
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谷氨酸信号调控玉米幼苗耐热性的生理生化机制 被引量:1
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作者 艾千群 杨慧琴 +2 位作者 杨思琦 刘宪斌 杨利云 《植物生理学报》 CAS CSCD 北大核心 2023年第10期1923-1932,共10页
本研究通过对玉米幼苗外施不同浓度α-酮戊二酸(α-OG)及谷氨酸(Glu)预处理分别提高幼苗内源和外源Glu水平,研究Glu信号对热胁迫(46℃,16 h)下玉米幼苗生长发育及耐热性的影响。结果表明:与蒸馏水处理相比,不同浓度α-OG及Glu预处理显... 本研究通过对玉米幼苗外施不同浓度α-酮戊二酸(α-OG)及谷氨酸(Glu)预处理分别提高幼苗内源和外源Glu水平,研究Glu信号对热胁迫(46℃,16 h)下玉米幼苗生长发育及耐热性的影响。结果表明:与蒸馏水处理相比,不同浓度α-OG及Glu预处理显著提高幼苗在热胁迫下存活率,并以40 mmol·L^(-1)α-OG(α-OG-40)及1 mmol·L^(-1)Glu(Glu-1.0)效果最佳。α-OG-40及Glu-1.0预处理显著提高热胁迫前后的幼苗株高、根长、总叶绿素含量、组织活力,降低了丙二醛(MDA)水平,显著增强幼苗整体素质。α-OG-40及Glu-1.0预处理显著提高热胁迫前后幼苗中可溶性蛋白、可溶性糖、脯氨酸及甜菜碱含量,增强幼苗的渗透调节能力。α-OG-40及Glu-1.0预处理显著提高热胁迫前后幼苗中抗坏血酸过氧化物酶(APX)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPX)、超氧化物歧化酶(SOD)及谷胱甘肽还原酶(GR)活性,加强活性氧清除能力,降低热胁迫对幼苗损伤。 展开更多
关键词 玉米幼苗 谷氨酸信号 生长发育 耐热性 生理及生化机制
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铝合金薄板FSLW界面hook沟成形特征及其对接头力学性能的影响
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作者 王金锴 毛育青 +4 位作者 戴浩 彭倩群 李智勇 刘泽宇 柯黎明 《航天制造技术》 2023年第6期7-12,共6页
本文选用1mm厚2A12-T4铝合金薄板进行搅拌摩擦搭接焊实验,通过改变焊接速度,研究其对焊接界面hook沟成形特征及接头力学性能的影响。结果表明,hook沟成形特征受焊接热输入影响较大,当采用95mm/min低焊接速度焊接时,由于焊接热输入大,塑... 本文选用1mm厚2A12-T4铝合金薄板进行搅拌摩擦搭接焊实验,通过改变焊接速度,研究其对焊接界面hook沟成形特征及接头力学性能的影响。结果表明,hook沟成形特征受焊接热输入影响较大,当采用95mm/min低焊接速度焊接时,由于焊接热输入大,塑性金属沿焊缝厚度方向上发生剧烈的环形迁移运动,促使hook尾部向上弯曲并堆积大量金属氧化物,有效搭接厚度较小;增加焊接速度至118mm/min时,焊接热输入降低,焊核区塑性金属挤压界面冷金属向上迁移的能力下降,导致hook沟尾部开始向下弯曲;继续提高焊接速度至235mm/min时,hook尾部受到塑性金属向下迁移的力大于向上迁移的力,迫使其向下弯曲,但在尾部产生了机械互锁效应,且焊缝有效搭接厚度明显增大,所获的接头拉剪力最大,高达3.790kN,其平均抗拉线强度为400N/mm,接头呈现明显的韧性断裂;继续增大焊接速度,则不利于提高接头成形质量。 展开更多
关键词 铝合金薄板 搅拌摩擦搭接焊 hook沟 成形特征 力学性能
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