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海藻酸钠复合天然化学物质涂膜对鲜切莲藕保鲜效果的影响

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江苏农业学报 2021年第1期37卷 175-184页

作者：张春洁 mohamed Hawali Bata Gouda 王俊豪彭思佳孔晓雪张秋婷罗海波南京师范大学食品与制药工程学院江苏南京210023

利用响应面法优化鲜切莲藕复合涂膜保鲜剂。根据不同保鲜剂的功能特性,选择7种保鲜剂(L-半胱氨酸、柠檬酸、草酸、L-精氨酸、海藻酸纳、亚麻籽胶、壳聚糖),考察不同质量分数保鲜剂对鲜切莲藕色泽的影响。以此单因素试验结果为基础,采用D... 详细信息

利用响应面法优化鲜切莲藕复合涂膜保鲜剂。根据不同保鲜剂的功能特性,选择7种保鲜剂(L-半胱氨酸、柠檬酸、草酸、L-精氨酸、海藻酸纳、亚麻籽胶、壳聚糖),考察不同质量分数保鲜剂对鲜切莲藕色泽的影响。以此单因素试验结果为基础,采用Design-Expert.V8.***.6.1软件进行响应面试验方案设计。结果表明,所选7种保鲜剂均可显著(P<0.05)延缓鲜切莲藕表面褐变;鲜切莲藕复合涂膜保鲜剂最佳组合为:0.50%海藻酸钠+0.27%L-半胱氨酸+0.76%柠檬酸。在此条件下鲜切莲藕贮藏12 d后色差值为1.86,菌落总数为2.69×10^(5)CFU/g,与回归方程预测值相近。表明海藻酸钠复合L-半胱氨酸和柠檬酸涂膜处理可有效延缓鲜切莲藕表面褐变和微生物腐败,维持较好的鲜切莲藕商品品质。

关键词：鲜切莲藕涂膜保鲜剂品质货架寿命

Tethering of Homo and Block Glycopolymer Chains onto Montmorillonite Surface by Atom Transfer Radical Polymerization

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Open Journal of Organic Polymer Materials 2012年第4期2卷 80-88页

作者： Amal Amin Heba Kandil Ahmed Ramadan mohamed Nader Ismail Chemistry Department Faculty of Science Helwan University Cairo Egypt Polymers & Pigments Department National Research Center Giza Egypt

Well-defined homo glycopolymer/montmorillonite (MMT) nanocomposite (gly1) was prepared successfully by the “grafting from” technique from the modified surface of MMT via surface initiated atom transfer radical polymerization (si-ATRP) of 3-O-methacryloyl-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose (gly) in the presence of Cu(I)Br/ bi- pyridyl at 90?C in xylene. Well-defined diblock copolymers (gly2, gly3, gly4 and gly5) were also synthesized via the same technique by using comonomers of methylmethacrylate (MMA) or styrene (St) with glycomonomer (gly) using the same catalytic system. The formed nanocomposites showed both intercalated and exfoliated structures, as judged by XRD and TEM measurements. Further analyses were performed on such nanocomposites to confirm their formation such as TGA and DSC. The structures of the attached polymers to MMT were characterized by 1H NMR.

关键词： Glycopolymers Polymer/Layered silicates Nanocomposites si-ATRP Montmorillonite

Study of the Central Heavy-Ion Collision with Emulsion at 4.5 A GeV/c

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Journal of Modern Physics 2011年第7期2卷 669-674页

作者： Alblomy Abd El-Daiem mohamed Abdo Khalifa Atef Abdel-hafiez 不详

We have investigated the main experimental characteristics(multiplicity correlation ,angular distributions and the analysis of emission of the shower particles produced at target fragments in central collisions of 28si+AgBr at 4.5AGeV/c has shown a formation of hadronic and baryonic clusters. Events of central collisions are defined, here, as those having no projectile charged fragments, even a singly charged one, emitted within 30 of the beam direction.

关键词： Multiplicity Correlation Multiplicity Distributions Hadronic Clusters Baryonic Clusters

甘肃枣子沟金矿床成矿过程分析——来自矿床地质特征、金的赋存状态及稳定同位素证据

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吉林大学学报（地球科学版） 2012年第4期42卷 1039-1054页

作者：曹晓峰 mohamed Lamine Salifou Sanogo 吕新彪何谋春陈超朱江唐然坤刘智张彬中国地质大学资源学院武汉430074 中国地质大学地质过程与矿产资源国家重点实验室武汉430074 北京矿通资源开发咨询有限责任公司北京100037

枣子沟金矿位于同仁-夏河-岷县金成矿带,矿区赋矿地层为三叠纪中统古浪堤组下段细碎屑岩及灰岩,并发育大量闪长质脉岩。矿体既产于地层中,也出现在脉岩或其接触带中,但其产状均严格受NE、NW及近SN向3组断裂构造控制,控矿构造为高角度的... 详细信息

枣子沟金矿位于同仁-夏河-岷县金成矿带,矿区赋矿地层为三叠纪中统古浪堤组下段细碎屑岩及灰岩,并发育大量闪长质脉岩。矿体既产于地层中,也出现在脉岩或其接触带中,但其产状均严格受NE、NW及近SN向3组断裂构造控制,控矿构造为高角度的张剪性及旋扭性断裂。热液成矿期可划分为黄铁矿-石英阶段,黄铁矿-毒砂-(闪锌矿-方铅矿-黄铜矿-辉银矿-绢云母-绿泥石-)石英阶段,辉锑矿-石英-方解石阶段及石英-方解石阶段。围岩蚀变类型主要为硅化、方解石化及绢云母化。环境扫面电镜及电子探针测试数据表明,金呈显微可见金存在于矿物裂隙和粒间隙中或以纳米不可见金捕获在载金矿物中。成矿期不同硫化物金的质量分数均高出检测限,其范围为0.003%～0.658%,平均值为0.257%。枣子沟金矿床具有卡林型金矿床的典型特征。氢氧同位素数据显示成矿流体主要来自大气水,硫同位素数据则表明硫主要来自沉积地层。其成矿过程可能为深切割断裂导通地下水,在深部被加热循环萃取围岩中成矿物质,并在浅表张性断裂中充填交代围岩,致使成矿物质沉淀富集成矿。金的迁移形式可能存在AuH3siO04、Au(HS)2-、H2Au(Sb,As)S02和HAu(Sb,As)S3-等多种迁移方式。成矿早阶段可能以金硅络合物的解体为主,成矿晚阶段则可能是硫氢(锑)络合物发生解体,致使金与硫化物同时沉淀,以显微纳米金的形式包含在硫化物中。

关键词：枣子沟微细浸染型金矿成矿期稳定同位素金的赋存状态

The Efficiency of a p-n Solar Diode as a Function of the Recombination Velocity within the Depletion Layer

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Optics and Photonics Journal 2012年第4期2卷 326-331页

作者： mohamed K. El-Adawi Najla S. Al-Shameri Physics Department College of Science for Girls Dammam University Dammam KSA Physics Department Faculty of Education Ain Shams University Cairo Egypt

The role of the carrier’s recombination velocity si within the depletion Layer of p-n junction solar cell and the external bias voltage Va across the junction in determining the current density “J” through the cell is revealed. The unsteady carrier diffusion equation is solved under illumination conditions considering a source spectral function G(λ). The efficiency of the device as a function of si , Va , G(λ) is obtained. Computations considering a silicon solar cell are given as an illustrative example.

关键词： Efficiency Diffusion Equation Recombination Velocity

Effect of a High silver Stress on the Element Transfers from a Smectite-Type Clay Substrate to Plants

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Green and Sustainable Chemistry 2012年第2期2卷 76-89页

作者： Khadija Semhi Norbert Clauer Sam Chaudhuri René Boutin mohamed Hassan Department of Geology Kansas State University Manhattan USA Laboratoire d’Hydrologie et de Géochimie de Strasbourg (CNRS-UdS) Strasbourg France Sultan Qaboos University Muscat Oman

Two species of radishes, Raphanus sativus and Raphanus raphanistrum, were grown in the laboratory in the same substrate consisting of a smectite-type clay, which was watered at the beginning of the experience with 50 ml of a solution containing either none or 1000, 2000 or 4000 mg/L of AgNO3, respectively. Occurrence of the toxic metal in the substrate outlines higher element uptakes by the cultivated species Raphanus sativus than by the wild species Raphanus raphanistrum, except for the highest degree of Ag pollution. After a one-month growth in the Ag-polluted substrate, Raphanus sativus was depleted in most of the major, trace and rare-earth elements, except for Al, Fe, Th, Ag and U that increased in the radishes from substrate polluted by 2000 mg/L of AgNO3, and Sr, Co, Ni, U and Ag that increased in the radishes from substrate polluted by 4000 mg/L of AgNO3. Raphanus raphanistrum was enriched in all elements except si, Na, Rb and K in the polluted substrate. The uptake was monitored by a cation-exchange process in the rhy-zosphere between mineral particles and the watering solution in the presence of various enzymes with specific activities that induced a variable uptake with the REEs being even fractionated. These activities most probably depend on combined factors, such as the plant species, and the chemical and physical properties of the substrate. The results obtained here reveal also that accumulation of nutrient elements and others in the plants is not uniform at a given Ag pollution of the substrate and therefore at a given Ag contamination in the same plant species.

关键词： Ag Pollution Plant-Growth Experiment Smectite-Type Clay Substrate Soil-Plant Element Transfers REE Fractionation

Microspherules-Bearing White Sandstone: Implication of Cosmic Impact Event near Jurassic-Cretaceous Boundary in West Central sinai, Egypt

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Journal of Geoscience and Environment Protection 2016年第7期4卷 53-65页

作者： Hanan S. Badawy Ahmed M. Zayed mohamed G. Shahien Geology Department Faculty of Science Beni-Suef University Beni-Suef Egypt

The presence of glass microspherules enclosing relict grains, shattered quartz and silicon carbide in white sandstone beds near the Jurassic-Cretaceous boundary in west central sinai indicates a cosmic impact event. Characterization of the impact microspherules and proposing a reasonable scenario for their origin are the aims of this work. Field observations, optical, binocular, scanning electron and high-resolution transmitted electron microscopy investigations and chemical analyses were carried out. The study revealed that glass microspherules have high Al2O3 and FeO contents and low CaO and MgO contents. The high content of Al2O3 indicates that the source of microtektite-like microspherules is attributed to the melting of a clay-rich sandstone and carbonaceous matter, while the high content of FeO indicates admixing with projectile matter. The reaction between silica and carbon was carried out under conditions of high temperature (T > 1000°C) and carbon (C/si > 1) which resulted in the production of silicon carbide with microdiamond intergrowth. Consequently, this intergrowth is in accordance with the impact origin via rapid condensation and growth within a vapor phase. In spite of the fact that no source crater has been recognized to date in the study area, the authors propose at least a single cosmic impact event scenario for the recorded glass microspherules in west central sinai. The impact excavated the Paleozoic siliciclastic sedimentary rocks and then the glass microspherules showered the area of study. The deposition of microtektite-like glass particles within the white sandstone beds of the Malha Formation took place in the fluvial plain terrestrial environment. This setting precluded severe post-depositional reworking, yielding preservation of the glass particles in a primary layer. Eventually, lateral migration of the braided channels led to the reworking of the microspherules layer and the spatial disper

关键词： Impact Glass Microtektites Ejecta Nubian Sandstone siC

Phosphate Solubilization by <i>Bacillus subtilis</i>and <i>Serratia marcescens</i>Isolated from Tomato Plant Rhizosphere

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Journal of Environmental Protection 2018年第3期9卷 266-277页

作者： Eman A. H. mohamed Azza G. Farag Sahar A. Youssef Botany and Microbiology Department Faculty of Science Damanhour University Damanhour Egypt Department of Biotechnology Faculty of Science Taif University Taif KSA Department of Virus and Phytoplasma Research Institute of Plant Pathology Research Agriculture Research Centre Cairo Egypt

Plants need phosphorus for many physiological activities in a form of phosphate anions. Three different bacterial strains (Bacillus subtilis PH, Serratia marcescens PH1, and Serratia marcescens PH2), recently isolated from tomato plant rhizosphere, have high phosphate solubilization index (si from 2.8 to 3.2) on Pikovskaya agar medium (which contains calcium phosphate). Moreover, phosphate release from calcium in Pikovskaya broth over 5 days is increasing with cell growth for the different isolates. The most efficient phosphate solubilization case is the mixed culture of the 3 strains (OD475 is almost 1). On the other hand, pH values decreased dramatically with time due to organic acids secretion and the maximum acidification level is recoded for Serratia marcescens PH2 (pH = 1.94). Interestingly, the isolates are resistance to important pesticides (oxamyl, thiophanate methyl, and captan) that are commonly used in the sampling area. This resistance is very favorable and increases the persistence of the phosphate solubilizing bacteria in contaminated soils. The isolates are therefore plant symbionts and growth promoting agents.

关键词： Phosphate Solubilization Pikovskaya Medium Bacillus subtilis Serratia marcescens

Thermal degradation of diethanolamine at stripper condition for CO 2 capture: Product types and reaction mechanisms

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