检索结果-南通市图书馆

The Ontogenesis and Ontogenetic Structure of Lagochilus proskorjakovii Ikram (Lamiaceae) Coenopopulations in Nuratau Mountain Range (Uzbekistan)

引用

American Journal of Plant Sciences 2016年第6期7卷 928-936页

作者： A. K. Akhmedov h. F. Shomurodov Z. b. Nomozova Department of botany and Plant Physiology Samarkand State University Samarkand Uzbekistan Institute of the Gene Pool of Plants and Animals Academy of Sciences Republic of Uzbekistan Tashkent Uzbekistan

Lagochilus proskorjakovii Ikram is a strict endemic in Nuratau ridge (north-western spurs of the mountain range of the Pamir-Alai). It grows as a part of Amygdalus bucharica and Perovskia scrophulariifolia formation, where the total projective cover of grass does not exceed 20%. In natural conditions growth, ontogeny of L. proskorjakovii is simple and complete. The duration of ontogenesis in the condition of Nuratau is no more than 22 - 23 years. Studied coenopopulations are normal, but are not complete. Coenopopulation self-maintenance is carried out by the seed of renewal. The characteristic spectrum of coenopopulation centered, with a peak in the middle-generative individuals. In most cases, specific developmental spectrum of coenopopulation coincides with the characteristic ones. The absence or small proportion of the young fraction in surveyed of coenopopulation is related to the elimination of young fragile individuals. According to the classification of “delta-omega”, the most of coenopopulations are maturing which confirms the positive state of coenopopulation demography. Studied the ontogeny and structure of adult endemic Nuratau established that the species belongs to caudexum shrubs, perennial that forms the axis of the short multicipital caudex. buds renewal is at a height of 2 - 3 cm above the substrate. Investigated coenopopulations L. proskorjakovii are successiveness conditions. In addition to the Artemisia juncea + Perovskia scrophulariifolia + Ferula ovina + Stipa hohenackeriana community 1st coenopopulation (CP) mature;the 2nd CP is mature which was a part of the Amygdalus bucharica + Perovskia scrophulariifolia + Prangos pobularia + bromus scoparius community;3rd CP is maturing being a part of Lonicera nummulariifolia + Perovskia scrophulariifolia + hypericum scabrum + bromus danthoniae community and the 4th CP is mature which occurred in Amygdalus bucharica + Ferula varia + Acroptilon repens + Taeniath

关键词： Demographic Characteristics Ontogenetic Spectrum Maturing Mature Plant Community Coenopopulation Types

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

Increase in reproductive ability of high-producing cows, and qualitative parameters of their offspring, under conditions of intensive milk production

引用

Asian pacific Journal of Reproduction 2018年第4期7卷 167-171页

作者： Khamidulla b.baimishev Murat h.baimishev Vasily S.Grigoryev Alexander P.Kokhanov Inna V.Uskova Ismagil N.Khakimov Department of Anatomy Obstetricsand SurgerySamara State Agricultural Academy446442Ust-KinelskiiUchebnaya ulSamaraRussia Department of Epizootology Pathologyand PharmacologySamara State Agricultural Academy446442Ust-KinelskiiUchebnaya ulSamaraRussia Department of Animal Nutrition and husbandry Volgograd State Agricultural University400002Universitetskii ProspVolgogradRussia Department of Animal Nutrition and husbandry Samara Stage Agricultural Academy446442Ust-KinelskiiUchebnaya ulSamaraRussia

Objective: To study the methods of increasing the reproductive qualities and indices of viability in the offspring of holstein cows under conditions of intensive milk production. Methods: Studies were conducted on 3 groups of holstein cows with 30 heads in each group. Animals of the experimental groups had a different length physiological period. The study focused on experimental groups of animals: the reproductive indicators, the viability of newborn calves, and their growth rate. All the digital materials of the experimental data were processed by the method of variation statistics for the significance of the difference of the compared parameters using the Student's criterion, adopted in biology and zootechnics. Results: Studies found that reduction of the duration of the service period, along with a simultaneous increase in the inter-lactation period to 80–90 days, increased the reproductive capacity of the cows, and enhances the viability of the offspring compared with their peers. Conclusions: The study revealed the optimal duration of the physiological periods in high-producing cows under conditions of intensive milk production technology.

关键词： Correction Fertility Labor Viability

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

Microstructure and mechanical properties of TiAl/TiAl joints brazed with a newly developed Ti–Ni–Nb–Zr quaternary filler alloy

引用

Progress in Natural Science:Materials International 2022年第6期32卷 758-768页

作者： h.S.Ren Y.L.Shang X.Y.Ren Y.J.Jing h.P.Xiong Y.Y.Cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

A novel Ti-Ni-Nb-Zr quaternary filler alloy with the composition of Ti-(19～25)Ni-(15～25)(Nb+Zr)(wt.%) was *** filler alloy was composed of(Ti,Nb)ss,(Ti,Zr,Nb)ss+(Ti,Zr)2Ni,α-Ti and Ti2Ni *** was fabricated into filler foil with a thickness of about 45 μm by a rapid solidification *** results indicate that the liquidus temperature of the Ti-Ni-Nb-Zr brazing alloy was about 978℃,and the brazing alloy presented excellent wettability on TiAl *** TiAl joint mainly consisted of β/b2 phase,Ti2Al,Ti2AlNi and α2-Ti3Al *** diffusion of Al atom from base metal to brazed seam led to the formation of Ti2Al and *** that no previously references on XRD pattern of Ti2AlNi compound can be found,Ti2AlNi cast alloy specimen was specially prepared and XRD peaks were specially *** micro-hardness and bending strength tests of the Ti2AlNi phase were carried out,and the results were 761 hV and 192 MPa,*** brazing parameters of 1010 ℃/10 min offered the joint shear strength of 280 MPa at room temperature,and the joints exhibited tensile strength of 372 MPa at room temperature and 340 MPa at 750 ℃,indicating that the newly developed filler alloy could offer a stable high-temperature strength.

关键词： TiAl brazing Filler alloy Microstructure Mechanical properties

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

Comparison on Immune Efficacy of Avian Influenza Virus Re-5 Strain and SS Strain in Guangxi Sanhuang Chickens

引用

Animal husbandry and Feed Science 2011年第5期3卷 23-25,29页

作者： LU cai-xia LI Jun-cheng hE Yin-e Guangxi Agricultural College Nanning 530007 China

[ Objective] To compare immune efficacy of avian influenza virus （AIV） Re-5 strain （hSN1 subtype） and SS strain （ h9 subtype） in Guangxi Sanhuang chickens. [Method] A total of 180 Sanhuang chickens were selected from a breeding chicken farm in Guilin City of Guangxi and assigned into four groups （ n = 45）. At 145 days old, the chickens in the group I and II were respectively inoculated with AIV Re-5 strain and AIV SS strain, but they were kept in cages separately. The two control groups were not inoculated. Antibody levels were determined at 170 days old. [ Result] The level of antibodies against AIV Re-5 strain was significantly higher in the chickens of the group I and group II than in the corresponding control groups, respectively （ P 〈 0.01 ）. The level of antibodies against AIV SS strain was not significantly different between the group I and its control group or between the group II and its control group. [ Conclusion] The antibody level of chickens can be increased by the AIV Re-5 strain but not by the AIV SS strain.

关键词： Guangxi Sanhuang chickens h5 vaccine h9 vaccine Immune efficacy

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

基于小波的扰动流场下细胞形态图像

引用

上海交通大学学报 2008年第2期42卷 274-278页

作者：韩亚刚蔡坤宝蔡绍皙蒋稼欢张莉重庆大学电气工程学院重庆400030 重庆大学通信工程学院重庆400030 重庆大学生物工程学院重庆400030

研制带后向台阶的流动腔实验装置,将内皮细胞成功地种植到流动腔底部,并在扰动流场作用下加以培养;应用基于多分辨率分析的二维小波图像压缩以及图像降噪与压缩方法,对图像进行了有效的降噪与压缩.流动腔内位于第1、2和3位置的细胞在扰... 详细信息

研制带后向台阶的流动腔实验装置,将内皮细胞成功地种植到流动腔底部,并在扰动流场作用下加以培养;应用基于多分辨率分析的二维小波图像压缩以及图像降噪与压缩方法,对图像进行了有效的降噪与压缩.流动腔内位于第1、2和3位置的细胞在扰动流场剪切应力作用12 h后,摄取它们的图像并进行了灰度直方图分析.分析表明,细胞形态与其所受的剪切应力有密切的关系,即细胞沿剪应力的方向发生拉伸现象,剪应力的幅值越大,拉伸越显著.反映在直方图上,细胞承受剪应力的增加导致其图像的直方图中心向灰度值低端移动.研究结果对流动腔实验装置的集成化、微型化和图像的实时处理与显示具有一定的价值.

关键词：细胞形态图像小波变换图像压缩图像降噪流动腔

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

应用于宽带Δ-∑ ADC的多级运算放大器

引用

华南理工大学学报（自然科学版） 2017年第1期45卷 42-47页

作者：徐肯蔡敏贺小勇华南理工大学电子与信息学院广东广州510640

为提高运算放大器的带内增益和带宽,提出了一款应用于长期演进(LTE)接收机中宽带Δ-∑模数转换器(ADC)的四级运算放大器.该运算放大器采用前馈Gm-C和密勒补偿相结合的混合型频率补偿方法,以保证运算放大器的稳定性.文中采用0.13μm1P6M ... 详细信息

为提高运算放大器的带内增益和带宽,提出了一款应用于长期演进(LTE)接收机中宽带Δ-∑模数转换器(ADC)的四级运算放大器.该运算放大器采用前馈Gm-C和密勒补偿相结合的混合型频率补偿方法,以保证运算放大器的稳定性.文中采用0.13μm1P6M CMOS工艺设计了一款高性能的四级运算放大器,并将该运算放大器应用于宽带Δ-∑ADC中.测试结果显示:该运算放大器在1.5 V供电电压下可获得72.8 d b的直流增益、442 Mhz的增益带宽积和101 V/μs的转换率;在相同的功耗和带宽下,该放大器的带内(0~10 Mhz)增益比传统的两级放大器提高了6 d b以上;采用该运算放大器的宽带Δ-∑ADC在10 Mhz的信号带宽下具有68 d b的信噪比和78 d b的无杂散动态范围.

关键词：运算放大器多级频率补偿宽带放大器 Δ-∑调制模数转换器

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

First-Principle Calculations of half-Metallic Double Perovskite La_(2)bb'O_(6)(b,b'=3d transition metal)

引用

Communications in Computational Physics 2013年第6期14卷 174-185页

作者： Y.P.Liu S.h.Chen h.R.Fuh Y.K.Wang Department of Physics National Taiwan Normal UniversityTaipei 116Taiwan Institute of Physics Academia SinicaTaipei 115Taiwan Graduate Institute of Applied Physics National Taiwan UniversityTaipei 106Taiwan Center for General Education and Department of Physics National Taiwan Normal UniversityTaipei 116Taiwan

In this paper,we present calculations based on density functional theory using generalized gradient approximation(GGA)in double perovskite structure La_(2)bb'O_(6)(b,b'=3d transition metal)out of 45(C_(2)^(10))combinational *** 4 types of magnetic states,namely,ferromagnetic(FM),ferrimagnetic(FiM),antiferromagnetics(AF),and nonmagnetic(NM)with full structure optimization,13 possible surviving,stable FM/FiM-hM materials containing 6 FM-hM materials(La_(2)ScNiO_(6),La_(2)CrCoO_(6),La_(2)CrNiO_(6),La_(2)VScO_(6),La_(2)VZnO_(6),and La_(2)VNiO_(6))and 7 FiM-hM materials(La_(2)VFeO_(6),La_(2)ZnCoO_(6),La_(2)TiCoO_(6),La_(2)CrZnO_(6),La_(2)CrMnO_(6),La_(2)ScFeO_(6),and La_(2)TiMnO_(6))are *** the correlation effect(GGA+U),there are 6 possible half-metallic stable,surviving(hM)materials containing 3 FMhM materials(La_(2)ScNiO_(6),La_(2)CrCoO_(6),and La_(2)CrNiO_(6))and 3 FiM-hM materials(La_(2)VFeO_(6),La_(2)ZnCoO_(6),and La_(2)TiCoO_(6)).

关键词： half-metallic materials double perovskites structure first-principle density functional theory

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

Transient growth in Poiseuille-Rayleigh-bénard flows of binary fluids with Soret effect

引用

Applied Mathematics and Mechanics(English Edition) 2016年第9期37卷 1203-1218页

作者： Jun hU D.hENRY h.bENhADID Xieyuan YIN Institute of Applied Physics and Computational Mathematics Beijing 100088China Laboratoire de Mecanique des Fluides et d'Acoustique CNRS/Universitd de LyonEcole Centrale de Lyon/universite Lyon 1/INSA de LyonECL36 avenue Guy de Collongue69134 Ecully CedexFrance Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China

The transient growth due to non-normMity is investigated for the Poiseuille- Rayleigh-benard problem of binary fluids with the Soret effect. For negative separation factors such as ψ = -0.1, it is found that a large transient growth can be obtained by the non-normal interaction of the two least-stable-modes, i.e., the upstream and downstream modes, which determine the linear critical boundary curves for small Reynolds numbers. The transient growth is so strong that the optimal energy amplification factor G（t） is up to 10^2 - 10^3. While for positive separation factors such as ψ = 0.1, the transient growth is weak with the order O（I） of the amplification factor, which can even be computed by the least-stable-mode. however, for both cases, the least-stable-mode can govern the long-term behavior of the amplification factor for large time. The results also show that large Reynolds numbers have stabilization effects for the maximum amplification within moderate wave number regions. Meanwhile, much small negative or large positive separation factors and large Rayleigh numbers can enlarge the maximum transient growth of the pure streamwise disturbance with the wavenumber α= 3.14. Moreover, the initial and evolutionary two-dimensional spatial patterns of the large transient growth for the pure streamwise disturbance are exhibited with a plot of the velocity vector, spanwise vorticity, temperature, and concentration field. The initial three-layer cell vorticity struc- ture is revealed. When the amplification factor reaches the maximum Gmax, it develops into one cell structure with large amplification for the vorticity strength.

关键词： binary fluid Soret effect transient growth Poiseuille-Rayleigh-benard flow

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

Photocatalytic degradation kinetics in Rhodamine b dye degradation with poriferous TiO_2 photocatalyst

引用

Journal of Marine Science and Application 2006年第2期5卷 60-64页

作者： WANG Zheng-ping JIAO cai-shan ChEN Xing-juan College of Chemical Engineering Harbin Engineering University Harbin 150001 China

A type of poriferous TiO2 material was prepared using cetyl trimethyl ammonium bromide as a template agent and butyl tetra titanate as a precursor. Through studying the photocatalytic kinetic activity of Rhodamine b photocatalytic degradation reaction with a UV-1601PC ultraviolet-visible spectrophotometer, the photocatalytic degradation process of Rhodamine b was found to not correspond to the first-order kinetic process completely. According to the reaction phenomenon, the photocatalytic degradation process of Rhodamine b with poriferous TiO2 involved two irreversible reactions. The kinetic model was tested using experimental data.

关键词： poriferous TiO2 photocatalyst kinetics Rhodamine b

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

The prevalence of hbsAg in Elderly hui Ethnicities residents In Ningxia

引用

Journal of hainan Medical University 2017年第9期23卷 67-69页

作者： hong-Lan cai hui-Yun Fan Zhi-Zhong Wang The department of Pain Qinghai Province People's HospitalQinghai Xining810007 Ningxia International Travel health care Center YinchuanNingxia750001China Department of Epidemiology and Statistic at School of Public health and Management Ningxia Medical UniversityYinchuan750004

Objective:To explore the prevalence of hbsAg in hui ethnicities aged 55 years and older. Methods:blood serum hbsAg biomarker was examined by immune colloidal gold dipstick for 6582 hui ethnicities, descriptive analysis applied to explore the distribution of prevalence of ***: Total of 372 subjects were positive of hbsAg with a prevalence of 4.68%;There were no significant differences between male and female for prevalence of hbsAg, however, an significant differences was detected among age groups,and the differences age group in older women. ALT and AST level higher in hbsAg positive group than those hbsAg negative ***: The hui elderly had a relatively lower prevalence of hbsAg than general population, further study needed to explore possible factors contribute to the low prevalence.

关键词： Elderly hui ethnicities hepatitis b surface antigen Prevalence

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

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：