检索结果-南通市图书馆

Competition of bloom-forming marine phytoplankton at low nutrient concentrations

Journal of Environmental Sciences 2011年第4期23卷 656-663页

作者： hanhua hu Jun Zhang Weidong Chen State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. School of Life Sciences Xiamen University Xiamen 361005 China Department of Gene Regulation and Drug Discovery Beckman Research Institute City of Hope National Medical Center Duarte CA 91010 USA

Competition of three bloom-forming marine phytoplankton （diatom Skeletonema costatum, and dinoflagellates Prorocentrum minimum and Alexandrium tamarense） was studied through a series of multispecies cultures with different nitrate （NaNO 3 ） and phosphate （NaH 2 PO 4 ） levels and excess silicate to interpret red tide algae succession. S. costatum outgrew the other two dinoflagellates in nitrate and phosphate replete cultures with 10 μmol/L Na 2 SiO 3 . Under nitrate limited （8.82 μmol/L NaNO 3 ） conditions, the growth of S. costatum was also dominant when phosphate concentrations were from 3.6 to 108 μmol/L. Cell density of the two dinoflagellates only increased slightly, to less than 400 and 600 cells/mL, respectively. Cell density of S. costatum decreased with time before day 12, and then increased to 4000 cells/mL （1.5 mg/L dry biomass） at NaNO 3 concentrations between 88.2 and 882 μmol/L with limited phosphate （0.36 μmol/L NaH 2 PO 4 ） levels. In addition, P. minimum grew well with a maximal cell density of 1690–2100 cells/mL （0.5–0.6 mg/L dry biomass）. Although S. costatum initially grew fast, its cell density decreased quickly with time later in the growth phase and the two dinoflagellates were dominant under the nitrate-limited and high nitrate conditions with limited phosphate. These results indicated that the diatom was a poor competitor compared to the two dinoflagellates under limited phosphate; however, it grew well under limited nitrate when growth of the dinoflagellates was near detection limits.

关键词： Alexandrium tamarense nitrate phosphate Prorocentrum minimum red tides Skeletonema costatum

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Role of two phosphohexomutase genes in glycogen synthesis in Synechocystis sp. PCC6803

引用

Chinese Science Bulletin 2013年第36期58卷 4616-4621页

作者： LIU Lian hu hanhua GAO Hong XU XuDong State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences

Phosphohexomutases catalyze the interconversion between hexose-6-phosphate and hexose-1-phosphate and play important roles in polysaccharide *** Synechocystis *** 6803,sll0726 is predicted to encode PGM(phosphoglucomutase),slr1334is predicted to encode a PGM/PMM(phosphomannomutase)bifunction *** comparison to the wild type,a sll0726-null mutant showed 3.4%PGM activity but 45%–69%glycogen ***-regulation of slr1334,an essential gene,by using a copper regulated promoter further decreased the PGM activity in the sll0726::KmrPpetE-slr1334 double mutant to 0.3%of the wild type ***,the glycogen content was not further decreased in *** vitro,recombinant Sll0726 or Slr1334 showed predicted enzyme *** results indicate that a relatively high level of glycogen can be maintained in Synechocystis mutants with low levels of PGM *** high PGM activity in the cyanobacterium may be required for turnover of glycogen or synthesis of other polysaccharides or oligosaccharides.

关键词：糖原合成集胞藻 e基因铂族金属多糖合成金属活性调控启动子突变体

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Producing Designer Oils in Industrial Microalgae by Rational Modulation of Co-evolving Type-2 Diacylglycerol Acyltransferases

引用

Molecular Plant 2017年第12期10卷 1523-1539页

作者： Yi Xin Yandu Lu Yi-Ying Lee Li Wei Jing Jia Qintao Wang Dongmei Wang Fali Bai hanhua hu Qiang hu Jin Liu Yantao Li Jian Xu Single-Cell Center CAS Key Laboratory of Biofuels and Shandong Laboratory of Energy Genetics Qingdao Institute of BioEnergy and Bioprocess TechnologyChinese Academy of Sciences Qingdao Shandong 266101 China Institute of Marine and Environmental Technology University of Maryland Center for Environmental Science and University of Maryland Baltimore CountyBaltimore MD 21202 USA Institute for Food and Bioresource Engineering and Department of Energy and Resource Engineering College of Engineering Peking University Beijing 100871China Center for Microalgal Biotechnology and Biofuels Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China Diatom Biology Group Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China Core Laboratory Qingdao Institute of BioEnergy and Bioprocess Technology Chinese Academy of Sciences Qingdao Shandong 266101 China University of Chinese Academy of Sciences Beijing 100049 China These authors contributed equally to this article.

Microalgal oils, depending on their degree of unsaturation, can be utilized as either nutritional supplements or fuels; thus, a feedstock with genetically designed and tunable degree of unsaturation is desirable to maximize process efficiency and product versatility. Systematic profiling of ex vivo （in yeast）, in vitro, and in vivo activities of type-2 diacylglycerol acyltransferases in Nannochloropsis oceanica （NoDGAT2s or NoDGTTs）, via reverse genetics, revealed that NoDGAT2A prefers saturated fatty acids （SFAs）, NoDGAT2D prefers monounsaturated fatty acids （MUFAs）, and NoDGAT2C exhibits the strongest activity toward polyunsaturated fatty acids （PUFAs）. As NoDGAT2A, 2C, and 2D originated from the green alga, red alga, and eukaryotic host ancestral participants of secondary endosymbiosis, respectively, a mecha- nistic model of oleaginousness was unveiled, in which the indigenous and adopted NoDGAT2s formulated functional complementarity and specific transcript abundance ratio that underlie a rigid SFA：MUFA：PUFA hierarchy in triacylglycerol （TAG）. By rationally modulating the ratio of NoDGAT2A＇：2C^D transcripts, a bank of N. oceanica strains optimized for nutritional supplement or fuel production with a wide range of degree of unsaturation were created, in which proportion of SFAs, MUFAs, and PUFAs in TAG varied by 1.3-, 3.7-, and 11.2-fold, respectively. This established a novel strategy to simultaneously improve productivity and quality of oils from industrial microalgae.

关键词： biofuels degree of unsaturation genetic engineering diacylglycerol acyltransferase Nannochloropsis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

铜山铜矿采场防灭火试验研究

引用

金属矿山 2001年第5期30卷 48-51页

作者：胡汉华长沙矿山研究院

介绍了铜山铜矿矿石自燃发火特征及用稀水泥浆阻燃灭火的方法。通过井下灭火试验 ,得出了铜山铜矿合理的阻燃灭火参数 ,证明在铜山铜矿矿石条件下 ,选用稀水泥浆灭火是可行的。

关键词：铜矿自燃阻燃稀水泥浆灭火试验灭火材料

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced expression of antifreeze protein genes drives the development of freeze tolerance in an Antarctica isolate of Chlorella vulgaris

引用

Progress in Natural Science:Materials International 2009年第9期19卷 1059-1062页

作者： huiying Li, Xiaoxiang Liu, Yali Wang, hanhua hu, Xudong Xu * State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

In adaptation to new environments, organisms may accumulate mutations within encoding sequences to modify protein characteristics or acquire mutations within regulatory sequences to alter gene expression levels. With the development of antifreeze capability as the example, this study presents the evidence that change in gene expression level is probably the most important mechanism for adaptive evolution in a green alga Chlorella vulgaris. C. vulgaris NJ-7, an isolate from Antarctica, possesses an 18S rRNA sequence identical to that of a temperate isolate, SAG211-11b/UTEX259, but shows much higher freeze tolerance than the later isolate. The chromosomal DNA/cDNA of four antifreeze genes, namely hiC6, hiC12, rpl10a and hsp70, from the two isolates of C. vulgaris were cloned and sequenced, and very few variations of deduced amino acid sequences were found. In contrast, the transcription of hiC6, hiC12 and rpl10a was greatly intensified in NJ-7 compared to that in UTEX259, which is correlated to the significantly enhanced freeze tolerance of the Antarctica isolate.

关键词： Chlorella vulgaris Antarctica isolate Temperate isolate Freeze tolerance Gene expression

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

复杂边坡滑动面确定的联合搜索法

引用

岩石力学与工程学报 2010年第4期29卷 814-821页

作者：曹平张科汪亦显胡汉华中南大学资源与安全工程学院湖南长沙410083

针对复杂边坡特点,提出改进的滑动面搜索变量选取方式,通过左、右出滑点和弧高控制滑动面位置,搜索变量取值范围不再需要经验假定。使用分区间搜索策略,以寻找最危险滑动面和潜在危险滑动面,同时也将搜索区域分割,增大算法搜索到全局最... 详细信息

针对复杂边坡特点,提出改进的滑动面搜索变量选取方式,通过左、右出滑点和弧高控制滑动面位置,搜索变量取值范围不再需要经验假定。使用分区间搜索策略,以寻找最危险滑动面和潜在危险滑动面,同时也将搜索区域分割,增大算法搜索到全局最优值的可能性。利用混沌优化算法和复合形法联合搜索算法确定复杂边坡的最小安全系数和滑动面,充分利用混沌搜索和复合形法各自的优点,有效地避免陷入局部最小值,并克服混沌优化耗时较长的不足。通过对复杂边坡实例的计算,结果证明,采用改进搜索变量的基本复合形法寻优成功率比传统搜索变量高出40%～60%。联合搜索法的最小安全系数集中于1.70～1.72,全局搜索能力远远优于基本复合形法。多级边坡工程算例的分析表明,该边坡的4条潜在滑动面,其安全系数与最小安全系数相差不超过7.6%,最小仅相差3.6%,但相应的滑动面位置与最危险滑动面完全不同。

关键词：边坡工程简化Bishop法搜索变量分区间搜索策略混沌优化复合形法

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

黄金矿山的通风系统改造问题探讨

引用

矿业研究与开发 2006年第5期26卷 79-82页

作者：胡汉华中南大学资源与安全工程学院湖南长沙410083

讨论了自然风压的特性及在黄金矿山通风系统改造中的利用问题,认为黄金矿山通风系统在改造前,首先应该优化通风网络。优化通风网络可应用通路法。非用风通路中不在用风通路中出现的分支可视为短路分支,应从通风网络中去掉。包含两条及... 详细信息

讨论了自然风压的特性及在黄金矿山通风系统改造中的利用问题,认为黄金矿山通风系统在改造前,首先应该优化通风网络。优化通风网络可应用通路法。非用风通路中不在用风通路中出现的分支可视为短路分支,应从通风网络中去掉。包含两条及以上的用风分支的通路可视为污风串联通路,应去掉某些分支消除这些通路,如果为了消除污风串联通路而使网络退化为不连通网络时,则只能通过调整井下作业时间去掉某些用风分支来解决。

关键词：通风网络优化自然通风通风系统改造风流短路污风串联

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

微藻高CO_2耐受机制及其在生物减碳领域的应用

引用

哈尔滨工业大学学报 2015年第4期47卷 9-14页

作者：李凤娟高大文胡晗华城市水资源与水环境国家重点实验室(哈尔滨工业大学) 哈尔滨150090 中国科学院水生生物研究所藻类生物学重点实验室武汉430072

为更好地利用微藻实现碳捕获和生物质生产,研究微藻高CO2耐受/驯化的过程及其基本机制尤为必要.综述了微藻对高CO2耐受的生理现象、可能的耐受机制及分子响应机制的研究进展,分析了耐受高CO2微藻在生物减排、生物燃料开发等领域的应用前... 详细信息

为更好地利用微藻实现碳捕获和生物质生产,研究微藻高CO2耐受/驯化的过程及其基本机制尤为必要.综述了微藻对高CO2耐受的生理现象、可能的耐受机制及分子响应机制的研究进展,分析了耐受高CO2微藻在生物减排、生物燃料开发等领域的应用前景,指出筛选耐受高CO2微藻并结合合理利用生理和基因工程手段以达到高效固碳的目标,是解决环境问题同时提高大规模微藻培养生产力的有效途径.

关键词：生物减排微藻高CO2耐受生物质转化

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pd@Ag nanosheets in combination with amphotericin B exert a potent cryptococcacidal effect

Pd@Ag nanosheets in combination with amphotericin B exert a ...

引用

2016全国中西医结合皮肤性病学术年会

作者： Chao Zhang Mei Chen Wei Fang Chen Ye hanhua hu Zhenzong Fa Jiu Yi Wan-qing Liao Shanghai Key Laboratory of Molecular Medical Mycology Shanghai Institute of Medical MycologySecond Military Medical University PLA Key Laboratory of Mycosis Department of Dermatology and VenereologyChangzheng Hospital State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Centre of Chemistry for Energy Materials and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University Department of Urology Changhai HospitalSecond Military Medical University UEM department Xinjiang Medical university

Silver nanoparticles have received considerable interest as new nanoantibiotics" with the potential to kill drug-resistant ***,a class of new core-shell nanostructures,Pd@Ag nanosheets(Pd@Ag NSs),were created using deposition techniques and demonstrated excellent inhibitory effects on various bacteria in *** this study,we evaluated the antifungal activity of Pd@Ag NSs against common invasive fungal *** these organisms,Cryptococcus neoformans complex species was most susceptible to Pd@Ag NSs,which exhibited potent antifungal activity against various molecular types or sources of cryptococcal strains including fluconazole-resistant *** anticryptococcal activity of Pd@Ag NSs was significantly greater than fluconazole and similar to that of amphotericin B(AmB).At relatively high concentrations,Pd@Ag NSs exhibited fungicidal activity against Cryptococcus spp.,which can likely be attributed to the disruption of cell integrity,intracellular protein synthesis,and energy ***,Pd@Ag NSs also exhibited strong synergistic cryptococcacidal effects at low concentrations in combination with AmB but exhibited much better safety in erythrocytes than AmB,even at the minimal fungicidal ***,Pd@Ag NSs may be a promising adjunctive agent for treating cryptococcosis,and further investigation for clinical applications is required.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

基于熵权的灰色沉降组合预测模型及应用

引用

矿业研究与开发 2007年第4期27卷 12-13,24页

作者：谢正文胡汉华中国计量学院计量技术工程学院浙江杭州310018 中南大学资源与安全工程学院湖南长沙410083

基于"组合预测"思想,提出了一种对多种常用预测模型进行熵权法计算权重的组合预测方法,从而可根据有限的沉降实测数据预测沉降发展。工程实例分析表明,基于熵权的灰色沉降组合预测模型能够充分挖掘各模型的有用信息,大大提高了预测精度。

关键词：沉降熵权灰色预测组合预测

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：