检索结果-南通市图书馆

Mineralogy and radioactivity of pegmatites from South Wadi Khuda area,Eastern Desert,Egypt

Chinese Journal Of geochemistry 2010年第4期29卷 343-354页

作者： Mohamed F.Raslan Mohamed A.Ali Mohamed g.el-Feky Nuclear Materials Authority P.O.Box 530El MaadiCairoEgypt

Radioactive minerals in pegmatites associated with granitic rocks are commonly encountered in the south of the Wadi Khuda area and found as dyke-like and small *** are observed within garnet-muscovite granites near the contact with older *** surveys indicated that the studied pegmatites vary in dimensions ranging from 2 to 10 m in width and from 10 to 500 m in *** are composed mainly of intergrowth of milky quartz,reddish-pink K-feldspar and plagioclase together with small pockets of *** radiometric measurements indicated that radioactivity in pegmatites is more than twice that of their enclosing country *** measurements revealed that the average contents of U and Th increase gradually from rocks of dioritic to granodioritic composition(1.5×10-6 U and 4.3×10-6 Th) and increase significantly in biotite granites(5.8×10-6 U and 15.2×10-6 Th) but drastically decrease in muscovite granites(2.2×10-6 U and 5.6×10-6 Th).The average contents of U and Th of anomalous pegmatites are 95.3×10-6 and 116.9×10-6,respectively,indicating their uraniferous *** the south of the Wadi Khuda area,pegmatites are low in average Th/U(1.4) and high in average U/K(35.6),which suggests that uranium concentrating processes did not affect the pegmatites,indicating poor *** investigations of the studied pegmatites revealed the presence of secondary uranium minerals(kasolite and autunite),in addition to zircon,thorite,apatite,garnet and *** and secondary radioactive mineralizations indicated that the mineralization is not only magmatic,but also *** microprobe analyses showed distinct cryptic chemical zoning within thorite where UO2 decreases from core to *** feature in thorite is sporadic,suggesting non-uniform redistributions of UO2 within thorite during magmatic processes.

关键词：放射性核素伟晶岩矿物学黑云母花岗岩平均含量沙漠埃及电子探针分析

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

Petrology, geochemistry, radioactivity, and M–W type rare earth element tetrads of el Sela altered granites, south eastern desert,Egypt

引用

Acta geochimica 2019年第1期38卷 95-119页

作者： A.M.el Mezayen M.A.Heikal M.g.el-Feky H.A.Shahin I.K.Abu Zeid S.R.Lasheen geology Department Faculty of Science Al Azhar University Nuclear Material Authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul Hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of el Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the el Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. It is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the el Sela shear zone. Major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/Hf and higher Y/Ho than the normal ratio are consistent with hydrothermal alteration. Most samples had rare earth element(REE)-patterns with an M-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, uranium-bearing, and uraniferous Fe and Mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： geochemistry REE-tetrad effect Radioactive minerals Radiometric measurements Qash Amer el Sela

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

Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

引用

Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： M.H.Abd-el Salam S.el-gamal M.Mohsen D.M.Abd el-Maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （g） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDMS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDMS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDMS loaded with different contents of filler has been studied. Mullins ratio （RM） was found to be dependent on the filler type and content. It was found that, RM increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. Moreover, the hysteresis in PDMS-CB composites was more pronounced than in PDMS-g composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDMS composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

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

Oxytocin improves testicular blood flow without enhancing the steroidogenic activity in Baladi goats

引用

Asian pacific Journal of Reproduction 2022年第5期11卷 223-230页

作者： Mohamed g.Hedia Amr S.el-Shalofy Department of Theriogenology Faculty of Veterinary MedicineCairo UniversityGiza 12211Egypt

Objective:To investigate the effects of a single oxytocin injection on plasma steroid concentrations,testicular blood flow measures(resistive and pulsatility indexes),and testicular echogenicity in Baladi ***:Twelve Baladi goat bucks were randomly allocated into 2 groups and received an intravenous injection of either 0.7 IU/kg oxytocin or normal saline 0.9%.Venous blood samples were collected,and testicular blood flow Doppler parameters(i.e.,peak systolic velocity,end-diastolic velocity,time average maximum velocity,resistive index,and pulsatility index)were assessed for supratesticular arteries in the left and right testes immediately before(0),and at 5,30,60,and 120 min after ***:Plasma concentrations of testosterone significantly decreased in the oxytocin group at 60 min post-treatment compared to the control group,whereas plasma concentrations of estradiol-17βwere not affected(P>0.05).Both resistive index and pulsatility index declined in the oxytocin group at 60 min post-treatment compared to the control group(Pel intensity increased at 30 min post-treatment in the oxytocin group compared to the control group(Pgnificantly increases testicular blood flow and decreases plasma testosterone concentrations in male Baladi goats.

关键词： Bucks Blood flow Doppler Estradiol-17β goat Oxytocin Testicular artery Testosterone

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

Releases of phosphate fertilizer industry in the surrounding environment:Investigation on heavy metals and polonium-210 in soil

引用

Journal of Environmental Sciences 2010年第9期22卷 1387-1397页

作者： M.Aoun A.g.el Samrani B.S.Lartiges V.Kazpard Z.Saad Lebanese Atomic Energy Commission Lebanese University Faculty of SciencesPlatform for Research and Analysis in Environmental Sciences Nancy University-LEM-ENSg/INPL-CNRS-15 Av.du Charmois

Distribution of Cu, Zn, Pb, Cr, Ni, Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determined. Nineteen sampling sites were distributed around the industrial zone on a surface area of about 100,000 m^2. Atomic absorption spectroscopy and Alpha spectroscopy were used to quantify the heavy elements and polonium-210, respectively. Investigation on a particle scale was conducted by TEM and SEM coupled to EDX and X-ray cartography to determine the nature of heavy elements carriers and their distribution. Heavy elements were mainly concentrated inside the particle size fraction 〈 50 μm. Their levels decreased with distance increasing from the industry. According to the reference soil, enrichment factors were about 10, 15, 32 and 100 times for Zn, Pb, Cu, and Cr, respectively inside the particle size fraction 〈 50 μm on the closest sites to the industry. The main contaminant sources were transport and storage of row materials and the free release of phosphogypsum waste. Heavy elements were entrapped inside agglomerates of sulfates, phosphates and iron oxihydroxides in a diffused shape. Polonium-210 with an enrichment factor of about 56, showed the same behavior of the spatial distribution of the trace elements.

关键词： heavy elements phosphogypsum fortilizer industry polonium-210 Alpha spectrometry

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

Production,characterization and biological activities of acidic exopolysaccharide from marine Bacillus amyloliquefaciens 3MS 2017

引用

Asian Pacific Journal of Tropical Medicine 2017年第7期10卷 715-725页

作者： Samah A.el-Newary Abeer Y.Ibrahim Mohsen S.Asker Manal g.Mahmoud Mohamed E.el Awady Department of Medicinal and Aromatic Plants Research National Research CentreDokkiCairoEgypt Microbial Biotechnology Department National Research CentreDokkiCairoEgypt

Objective: To evaluate in-vitro antioxidant, anti-inflammatory and antitumor abilities against human breast adenocarcinoma(MCF7) and human prostate cancer(PC3) as well as the suppressor effect of bacterial exopolysaccharide(BAEPS) on Ehrlich ascites carcinoma(EAC). Methods: In-vitro antioxidants characters of BAEPS were determined using various methods, while anti-inflammatory activity was estimated against cyclooxygenase(COX-1 and COX-2). In-vitro study, anticancer against MCF7 and PC3 were assessed by the mitochondrial dependent reduction of yellow MTT. In in-vivo study against EAC progression, mice were inoculated with EAC cells and then were orally administered BAEPS at 200 mg/kg after 24 h(equals to 0.10 of determined LD50)/10 d. Results: BAEPS was acidic exopolysaccharide contained uronic acid(12.3%) and sulfate(22.8%) with constitution of glucose, galactose and glucuronic acid in a molar ratio1.6: 1.0: 0.9, respectively, with a molecular mass of 3.76伊104 g/mol. BAEPS appeared potent antioxidant characters as free radical scavenging, oxygen reactive species scavenging and metal chelation, while its reducing power was low. BAEPS showed selective anti-inflammatory activity against COX-2 than COX-1, COX-2 selective. BAEPS exhibited potent and selective effect to breast cell cancer MCF7, the death percentage was 65.20% with IC_(50)=70 μg/m L and IC_(90)=127.40 μg/m L. BAEPS decreased counted viable EAC cells and induced non-viable cells. BAEPS improved all assessed hematological parameters. These improvements were reflected in the increasing median survival time and significant increment(Pgood margin of safety. The anti-tumor activity of BAEPS may be due to its content from sulfated groups and uronic acids and they have antioxidant and anti-inflammatory properties.

关键词： Antioxidant Anti-inflammatory Anti-tumor Ehrlich ascites carcinoma Exopolysaccharide Bacillus amyloliquefaciens

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

Development of Cd-doped Co Nanoparticles Encapsulated in graphite Shell as Novel electrode Material for the Capacitive Deionization Technology

引用

Nano-Micro Letters 2013年第4期5卷 303-313页

作者： Nasser A.M.Barakat Khalil Abdelrazek Khalil Ahmad g.el-Deen Hak yong kim Organic Materials and Fiber Engineering Department Chonbuk National University Chemical Engineering Department Minia University Mechanical Engineering Department (NPST) King Saud University Dept of Bionano System Engineering College of Engineering Chonbuk National University

Because of the low energy requirement and the environmentally safe byproducts, the capacitive deionization water desalination technology has attracted the attention of many researchers. The important requirements for electrode materials are good electrical conductivity, high surface area, good chemical stability and high specific capacitance. In this study, metallic nanoparticles that are encapsulated in a graphite shell(Cd doped Co/C NPs) are introduced as the new electrode material for the capacitive deionization process because they have higher specific capacitance than the pristine carbonaceous materials. Cd doped Co/C NPs perform better than graphene and the activated carbon. The introduced nanoparticles were synthesized using a simple sol gel technique. A typical sol gel composed of cadmium acetate, cobalt acetate and poly(vinyl alcohol)was prepared based on the polycondensation property of the acetates. The physiochemical characterizations that were used confirmed that the drying, grinding and calcination in an Ar atmosphere of the prepared gel produced the Cd doped Co nanoparticles, which were encapsulated in a thin graphite layer. Overall, the present study suggests a new method to effectively use the encapsulated bimetallic nanostructures in the capacitive deionization technology.

关键词： Capacitive deionization Water desalination Bimetallic nanoparticles Specific capacitance

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

geochemistry, mineralogy, and radioactivity of the Abu Furad Area, Central Eastern Desert, Egypt

引用

Acta geochimica 2019年第2期38卷 307-326页

作者： A.M.el Mezayen E.K.Abu Zeid W.S.Hosny M.g.el-Feky S.M.Omar S.A.Taalab geology Department Faculty of Science Al Azhar University Nuclear Material Authority Cairo Egypt

Abu Furad is in the Central Eastern Desert,Egypt. It comprises metasediments, metavolcanics,metagabbros, syn-to late-orogenic granites, and post-orogenic granites, in addition to numerous dykes and veins of different shapes and composition invading all the older rocks cropping out in the study area. Field, petrographic,mineralogical, and chemical investigations led to the classification of Abu Furad granites as quartz diorite, tonalite,granodiorite, and *** oxide and trace element data revealed that the syn-to late-orogenic granites and post-orogenic granites are peraluminous. Syn-to lateorogenic granites originated from calc-alkaline volcanic arc–related magma; while the post-orogenic granites(syenogranite) are highly fractionated, calc-alkaline granite from a within plate regime. Radiometrically, the studied quartz diorite, tonalite, and granodiorite had lower uranium and thorium contents and higher eU/eTh ratios than the syenogranites. This may indicate that the syn-to late-orogenic rocks originated from sources depleted in these elements. The average e Th/eU ratio of syenogranites was higher than that of average continental crust, suggesting that the syenogranites are relatively depleted in U. The studied altered syenogranites were strongly enriched in U and Th compared to the Earth's crust. On the other hand, the average of e U in pegmatites is lower than the global average for uraniferous pegmatites. The most recorded accessory minerals in the altered syenogranites were thorite, fergusonite, samarskite, columbite, zircon, monazite, xenotime,apatite, fluorite, sphene, atacamite, and malachite, in addition to chromium and nickel inclusions.

关键词： Hydrothermal alterations Major oxide and trace elements Radiometry Mineralogy geochemistry Altered syenogranites Egypt

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

Transition of children with inflammatory bowel disease: Big task,little evidence

引用

World Journal of gastroenterology 2009年第30期15卷 3744-3747页

作者： Wael el-Matary Division of Pediatric gastroenterology Hepatology and NutritionStollery Children's HospitalFaculty of MedicineUniversity of AlbertaEdmontonAlberta T6G 2J3Canada

Children with chronic long-term disorders need to move to the adult practice at some point in their life. Establishing a smooth and efficient transition process is a complicated task. Transition of medical care to adult practice is def ined as the purposeful planned movement of adolescents and young adults with chronic physical and medical conditions from child-centered to adultoriented health care systems. This step is of the utmost importance for several reasons. There is an obvious deficiency of research in this area especially when it comes to pediatric inflammatory bowel disease (IBD). There is a considerable difference in individual practice among different centers. Also, age of transition varies among different countries and sometimes, even within the same country, transition age may vary among different provinces and districts! Interestingly, local politics and many factors other than children’s welfare often play a role in deciding the age that older children move to adult practice at. This review discusses transition of children with IBD in view of the available evidence.

关键词： Transition Inflammatory bowel disease Adolescent

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

The Essential Oil of Ocimum americanum from Senegal and gambia as a Source of Methyleugenol for the Control of Bactrocera dorsalis, Fruit Fly

引用

Journal of Agricultural Chemistry and Environment 2024年第1期13卷 133-141页

作者： Yoro Tine Antonio Alain Coffi Sinzogan Ousmane Ndiaye Cebastiana Sambou Alioune Diallo Ismaila Mbenga Kemo Badji el Hadji Omar Dieng Assa Balayara Jeanne Diatta Cheikhouna gaye Julien Paolini Jean Costa Alassane Wele Saliou Ngom Laboratoire de Chimie Organique et Thérapeutique Faculté de Médecine Pharmacie et Odontologie Université Cheikh Anta Diop Dakar Sénégal Faculte des Sciences Agronomiques Universite d’Abomey Calavi Cotonou Benin Ecole Nationale Supérieure d’Agriculture (ENSA) Université Iba Der Thiam de Thiès Thiès Sénégal Direction de la Protection des Végétaux Rufisque Sénégal Laboratoire de Chimie des Produits Naturels Université de Corse Corte France National Agricultural Research Institute (NARI) Sere Kunda Gambia Institut Sénégalais de Recherches Agricoles (ISRA) Dakar Sénégal

The fruit fly, Bactrocera dorsalis (Diptera: Tephritidae) is one of the most important pests in all mango-producing areas, particularly in West Africa. In Senegal, O. americanum leaves have been used for several years to control this fly. However, to our knowledge, no chemical studies have been carried out. Thus, the aim of this study is to determine the chemical composition of the essential oil of O. americanum leaves collected in Senegal and gambia. The essential oil obtained by hydrodistillation of these leaves is analyzed by gC/FID and gC/MS. Yields of essential oils from O. americanum leaves are 3.84% and 2.13%, respectively. Analysis of these essential oils by gC/FID and gC/MS allowed the identification of 23 compounds representing almost 100% of the total compositions. These essential oils are mainly dominated by methyleugenol (72.0% and 75.8%, respectively). Other components in significant percent are trans-β-caryophyllene (13.9% and 13.0%, respectively), germacrene D (4.1% and 3.7%, respectively), β-elemene (3.3% and 0.9%, respectively). Due to the high methyleugenol content, this study explains the attractive potential of O. americanum towards B. dorsalis. In perspective, we plan to evaluate the attractive effect of the essential oil and leaf powder of O. americanum against B. dorsalis, a real pest of mango orchards in Senegal.

关键词： Ocimum americanum Essential Oils Methyleugenol Bactrocera dorsalis gC/MS

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：