检索结果-南通市图书馆

Vegetation composition differentiation and species-environment relationships in the northern part of Isfahan Province, Iran

引用

Journal of Arid Land 2017年第2期9卷 161-175页

作者： Hadi KARGAR-CHIGANI seyed akbar javadi Ghavamodin ZAHEDI-AMIRI seyed Jamaleddin KHAJEDDIN Mohamad JAFARI Department of Range Management Science and Research Branch Islamic Azad University Faculty of Natural Resources University of Tehran Range and Watershed Management Division Department of Natural Resources Isfahan University of Technology

A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axi

关键词： rangeland classification ordination multivariate analysis plant groups Isfahan Province

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

Fabrication of (Ti,Hf)-rich NiTiHf Alloy Using Graphitic Mold and Crucible

引用

Journal of Materials Science & Technology 2014年第3期30卷 280-284页

作者： Mahdi Moshref-javadi Majid Belbasi seyed Hossein seyedein Mohammad Taghi Salehi School of Metallurgy & Materials Engineering Iran University of Science & Technology (IUST)

In this research, fabrication of a （Ti,Hf）-rich NiTiHf alloy by using vacuum induction melting （VIM） process and a graphitic crucible was investigated. For this purpose, casts with the nominal composition of Ni49Ti38Hf15 were prepared in graphitic crucible and mold. Optical microscopy （OM）, scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDS）, X-ray diffraction （XRD）, and differential scanning calorimetry （DSC） tests were employed to characterize the samples. Results demonstrated that microstructure of the first cast was composted of a B2 austenite phase as well as a great amount of two differently formed （Ti,Hf）C carbides. Moreover, no austenite ＊-＊ martensite transformation peak was detected in the DSC curve of this sample, indicating a drastic decline in the transformation temperatures. In the succeeding cast, however, owing to the formation of carbide layers on the inner surfaces of the graphitic crucible and mold during the initial casting process, the amounts of carbides decreased remarkably. This cast exhibited transformation temperatures above 100℃, while XRD pattern denoted the presence of B19t monoclinic martensite phase at room temperature. All in all, results confirmed that VIM process using graphitic mold and crucible can be considered as an appropriate method for the fabrication of （Ti,Hf）-rich NiTiHf high temperature shape memory alloys.

关键词： High temperature shape memory alloys NiTi Martensite Casting Transformation temperatures Microstructure

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

Antiviral optical techniques as a possible novel approach to COVID-19 treatment

引用

Journal of Innovative Optical Health Sciences 2021年第3期4卷 1-18页

作者： Fereshteh Moshfegh Farshad Khosraviani Negar Moghaddasi seyedeh Fatemeh seyed javadi Limoodi Ebrahim Boluki Department of Dentistry New Vision University 1a Evgeni Mikeladze StreetTbilisi 0159Georgia School of Dentistry University of California Los Angeles10833 Le Conte CHSCA 90095USA School of Dentistry Shiraz University of Medical Sciences Zand Street P.O. School of Dentistry Tehran University of Medical Sciences North Karegar Street P.O. Blood Transfusion Research Center High Institute for Research&Education in Transfusion Medicine TehranIran

The current pandemic SARS-CoV-2(also known as 2019-nCoV and COVID-19)viral infection is growing globally and has created a disastrous situation all over the *** of the biggest challenges is that no drugs are available to treat this life-threatening *** no drugs are available for definitive treatment of this disease and the mortality rate is very high,there is an utmost need to cure the infection using novel *** study will point out some new antimicrobial technologies that have great potentials for eradicating and preventing emerging *** can be considered as treatments of choice for viral infections in the future.

关键词： SARS-CoV-2 COVID-19 light therapy photodynamic therapy photocatalysis ARDS

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

Thermal performance of a single U-tube ground heat exchanger:A parametric study

引用

Journal of Central South University 2021年第11期28卷 3580-3598页

作者： seyed Soheil MOUSAVI AJAROSTAGHI Hossein javadi seyed Sina MOUSAVI Sébastien PONCET Mohsen POURFALLAH Faculty of Mechanical Engineering Babol Noshirvani University of TechnologyBabol 47148-71167Iran Faculty of Mechanical Engineering Mazandaran University of Science and TechnologyBabol 47166-85635Iran Faculty of Civil Engineering Babol Noshirvani University of TechnologyBabol 47148-71167Iran Department of Mechanical Engineering Universitéde Sherbrooke2500 Boulevard de l'UniversitéSherbrookeQuébecJ1K 2R1Canada

In this research,the thermal performance of a single U-tube vertical ground heat exchanger is evaluated numerically as a function of the most influential flow parameters,namely,the soil porosity,volumetric heat capacity,and thermal conductivity of the backfill material,inlet volume flow rate,and inlet fluid *** results are discussed in terms of the variations of the heat exchange rate,the effective thermal resistance,and the effectiveness of the ground heat *** show that the inlet volume flow rate,inlet fluid temperature,and backfill material thermal conductivity have significant effects on the thermal performance of the ground heat exchanger,such that by decreasing the inlet volume flow rate and increasing the backfill material thermal conductivity and inlet fluid temperature,the outlet fluid temperature decreases *** the contrary,the soil porosity and backfill material volumetric heat capacity have negligible effects on the studied ground heat exchanger’s thermal *** lowest inlet fluid temperature reaches a the maximum effective thermal resistance of borehole and soil,and consequently the minimum heat transfer rate and ***,multilinear regression analyses are performed to determine the most feasible models able to predict the thermal properties of the single U-tube ground heat exchanger.

关键词： single U-tube ground heat exchanger numerical simulation heat exchange rate effectiveness multilinear regression analysis

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

Analysis of the glucokinase gene in Iranian families with maturity onset diabetes of the young

引用

Journal of Diabetes Mellitus 2013年第4期3卷 192-198页

作者： Meisam javadi Houshang Rafatpanah seyed Morteza Taghavi Jalil Tavakolafshari Rashin Ganjali Narges Valizadeh seyedeh Seddigheh Fatemi Bu-Ali Research Center Mashhad University of Medical Sciences Mashhad Iran Immunogenetics Department Immunology Research Center Bu-Ali Research Center Mashhad University of Medical Sciences Mashhad Iran Internal Medicine Department Ghaem Hospital and Endocrine Research Center Mashhad University of Medical Sciences Mashhad Iran Mashhad University of Medical Sciences Mashhad Iran

Non insulin dependent diabetes mellitus (NIDDM) as a most common form of diabetes is a major public health problem;there is a subgroup of NIDDM patients who develop the disease at an early age and show a dominant mode of inheritance. This type is nominates Maturity onset diabetes of the young (MODY). The prevalence of MODY is difficult to access, and patients with MODY genes mutations are often identified during routine screening for other purposes. MODY2 was linked to glucokinase gene (GCK) mutations, and accounted for 8% to 56% of MODY, with the highest prevalence found in the southern Europe. The aim of this study was to examine the prevalence and nature of mutations in GCK gene in Iranian paients. We have screened GCK mutations by polymerase chain reaction (PCR);single stranded conformation polymorphism (SSCP) technique in 12 Iranian families with clinical diagnosis of MODY, included 30 patients (8 males and 22 females) and their 21 family members. PCR products with abnormal mobility in denaturing gradient gel electrophoresis (DGGE) were directly sequenced. We identified 6 novel mutations in GCK gene in Iranian families (corresponding to 36.6% prevalence). Our findings and the last study on MODY1 highlight that in addition to GCK, other MODY genes such as MODY3 and MODYX may play a significant role in diabetes characterized by monogenic autosomal dominant transmission. There is an important point that the genetic recognation can be used to pre-symptomatically identify family members at risk for developing MODY.

关键词： Maturity Onset Diabetes of the Young 2 (MODY2) Glucokinase (GCK) Mutation SSCP PCR

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

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

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：