检索结果-南通市图书馆

Dynamics of the ruminal microbial ecosystem, and inhibition of methanogenesis and propiogenesis in response to nitrate feeding to Holstein calves

引用

Animal Nutrition 2021年第4期7卷 1205-1218页

作者： Abimael Ortiz-Chura Jose Gere Gisela Marcoppido Gustavo Depetris Silvio Cravero Claudia Faverin cesar pinares-patino Angel Cataldi d Maria E.Ceron-Cucchi Institute of Pathobiology CICVyA National Institute of Agricultural TechnologyIPVetUEDD INTA-CONICETHurlinghamC1686Argentina Engineering Research and Development Division National Technological University(UTN)National Scientific and Technical Research Council(CONICET)Buenos AiresC1179Argentina Agricultural Experimental Station of Balcarce National Institute of Agricultural Technology(INTA)BalcarceB7620Argentina Institute of Agrobiotechnology and Molecular Biology IABIMONational Institute of Agricultural Technology(INTA)National Scientific and Technical Research Council(CONICET)HurlinghamC1686Argentina The Agribusiness Group Lincoln UniversityPO Box 85016Lincoln7674New Zealand

It is known that nitrate inhibits ruminal methanogenesis,mainly through competition with hydrogenotrophic methanogens for available hydrogen(H2)and also through toxic effects on the ***,there is limited knowledge about its effects on the others members of ruminal microbiota and their *** this study,we investigated the effects of dietary nitrate inclusion on enteric methane(CH4)emission,temporal changes in ruminal microbiota,and fermentation in Holstein *** animals were maintained in individual pens for 45 *** were randomly allocated to either a control(CTR)or nitrate(NIT,containing 15 g of calcium nitrate/kg dry matter)*** emissions were estimated using the sulfur hexafluoride(SF6)tracer *** microbiota changes and ruminal fermentation were evaluated at 0,4,and 8 h *** this study,feed dry matter intake(DMI)did not differ between dietary treatments(P>0.05).Diets containing NIT reduced CH4 emissions by 27%(g/d)and yield by 21%(g/kg DMI)compared to the CTR(P0.05)but differed with time,and post-feeding(P<0.05).Increases in the concentrations of ruminal ammonia nitrogen(NH3-N)and acetate were observed,whereas propionate decreased at 4 h post-feeding with the NIT diet(P<0.05).Feeding the NIT diet reduced the populations of total bacteria,total methanogens,Ruminococcus albus and Ruminococcus flavefaciens,and the abundance of Succiniclasticum,Coprococcus,Treponema,Shuttlewortia,Succinivibrio,Sharpea,Pseudobutyrivibrio,and Selenomona(P<0.05);whereas,the population of total fungi,protozoa,Fibrobacter succinogenes,Atopobium and Erysipelotrichaceae L7 AE11 increased(P<0.05).In conclusion,feeding nitrate reduces enteric CH4 emissions and the methanogens population,whereas it decreases the propionate concentration and the abundance of bacteria involved in the succinate and acrylate pathways.D

关键词： Methane emission Nitrate Microbiota Ruminal fermentation

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

Leaching kinetics in cyanide media of Ag contained in the industrial mining-metallurgical wastes in the state of Hidalgo, Mexico

引用

International Journal of Mining Science and Technology 2014年第5期24卷 689-694页

作者： Juan Hernandez Francisco patino Isauro Rivera Iván Alejandro Reyes Misrael Uriel Flores Julio cesar Juarez Martín Reyes Research Centre in Materials and Metallurgy Autonomous University of Hidalgo Pachuca 42184 Mexico

The leaching kinetics in cyanide media of the silver contained in the Dos Carlos waste tailings at the City of Pachuca de Soto, Hidalgo State, Mexico were carried out. The used material contained the following chemical composition: 56 10-6of Ag, 0.6 10 6of Au and 70.43%(by weight) of SiO2; 7.032%(by weight) of Al2O3; 2.69%(by weight) of Fe; 0.46%(by weight) of Mn; 3.98%(by weight) of K2O; 3.34%(by weight) of CaO; 2.50%(by weight) of Na2O; 0.04%(by weight) of Zn; 0.026%(by weight) of Pb. The mineralogical phases present were the following: Silica, albite, argentite, berlinite, orthoclase, potassium jarosite, and natrojarosite. In the leaching kinetics in cyanide media, and under the studied conditions,the effect of the CN concentration on the reaction rate has no effect on the whole process of alkaline cyanidation, of which the reaction order is n 0. Temperature has an effect on the cyanidation rate of the reaction, with an activation energy of 47.9 KJ/mol. At the same time, when the particle size decreases there is an increase in the reaction rate, which is inversely proportional to the particle diameter; when increasing the NaOH concentration there is an increase in the reaction rate Kexp, with a reaction order(n) of 0.215 under the studied ranges.

关键词： Silver Waste tailings Cyanidation Leaching

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

Columnar joints in the patino Formation sandstones, Eastern Paraguay： a dynamic interaction between dyke intrusion, quartz dissolution and cooling-induced fractures

引用

Episodes 2008年第3期31卷 302-308页

作者： Victor Fernandez Velazquez Paulo cesar Fonseca Giannini Claudio Riccomini Alethea Ernandes Martins Sallun Jorge Hachiro Celso de Barros Gomes Eseola de Artes Ciencias e Humanidades Universidade de Sao Paulo Rua Arlindo Betio 1000 03828-080 Sao Paulo Brasil Instituto de Geociencias Universidade de Sao Paulo Rua do Lago 562 05508-080 Sao Paulo Brasil Insfituto Geolegico Secretaria do Meio Ambiente Av. Miguel Estefano 3900 04301-903 Sao Paulo Brasil.

The Patiho Formation sandstones, which crop out in Aregud neighborhood in Eastern Paraguay and show columnar joints near the contact zone with a nephelinite dyke, have as their main characteristics the high pro- portion of syntaxial quartz overgrowth and a porosity originated from different processes, initially by dissolu- tion and later by partial filling and fracturing. Features like the presence of floating grains in the syntaxial cement, the transitional interpenetrative contact between the silica-rich cement and grains as well as the intense fracture porosity are strong indications that the cement has been formed by dissolution and reprecipita- tion of quartz from the framework under the effect of thermal expansion followed by rapid contraction. The increase of the silica-rich cement towards the dyke in association with the orthogonal disposition of the columns relative to dyke walls are indicative that the igneous body may represent the main heat source for the interstitial aqueous solutions previously existing in the sediments. At macroscopic scale, the increasing of inter- nal tensions in the sandstones is responsible for the nucleation of polygons, leading to the individualization of prisms, which are interconnected by a system of joints, formed firstly on isotherm surfaces of low tem- perature and later on successive adjacent planes towards the dyke heat source.

关键词：柱状连接砂岩巴拉圭南美洲动力学

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

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

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

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：