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Fabrication of hollow silica microspheres utilizing a hydrothermal approach

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Chinese Chemical Letters 2014年第4期25卷 627-629页

作者： haitham mohammad Abdelaal Ceramics Department The National Research Center

Hollow silica microspheres （HSmSs） have been successfully fabricated via a facile hydrothermal route using D-glucose as the sacrificial template and sodium silicate powder as the silica precursor. The resulting silica hollow particles were characterized by scanning electron microscopy （SEm）, transmission electron microscopy （TEm）, X-ray diffraction （XRD）, and infrared spectroscopy （IR）. The surface area was determined using the BET method. SEm and TEm images exhibited micro-sized silica hollow particles with a size of -1.5μm.

关键词： Silica Hollow materials Glucose Hydrothermal method

The chromite deposits associated with ophiolite complexes, Southeastern Desert, Egypt: Petrological and geochemical characteristics and mineralization

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Chinese Journal Of Geochemistry 2006年第4期25卷 307-317页

作者： Gehad m. saleh Nuclear materials Authority P.O.Box: 530 El Maadi Cairo Egypt

The podiform chromitites occur in a well-preserved mantle sequence consisting of lherzolite-harzburgite with abundant lenses of olivine dunite. The podiform chromitite deposits are common as small and irregularly shaped masses in the Southeastern Desert (SED) of Egypt. The podiform chromitites exhibit a wide range of compositions from high Cr to high Al varieties. The Cr of chrome spinel ranges from 0.67 to 0.88 in olivine-dunite, quite similar to that of the high-Cr chromitite, whereas it is around 0.62 in lherzolite-harzburgite. Primary hydrous mineral inclusions, amphibole and phlogopite, in chrome spinel have been reported for the first time from the Pan-African Proterozoic podiform chromitites. On the other hand, petrographic and geochemical evidence suggests that podiform chromitites in the SED of Egypt were formed as a result of crystallization of mafic melts, probably of boninitic composition, the boninitic parental magmas were probably produced by a second stage of melting above a subduction zone. Three types of chromite ores can be distinguished within the SED of Egypt: (a) sulphide-poor podiform ores; (b) brecciated ores; and (c) sulphide-rich ores. Two textural types of inclusions in chromite are distinguished: (1) primary silicate inclusions generally have high mg-number (>96), Cr and Ni, and are dominated by pargasitic amphibole, forsterite, diopside, enstatite and Na-phlogopite. A diversity of primary and secondary platinum group minerals (PGm) is described from the chromitites, including alloys, sulphides, sulpharsenides and arsenides of Ru, Os, Ir, Rh, Ni, Cu, Fe and Co; (2) in addition to primary PGm and hydrous silicates, the fluids are of low to moderate salinity, sodium-dominated aqueous solutions with complex gas contents. Variable amounts of water, hydrogen, hydrocarbons, carbon dioxides and nitrogen have been determined in inclusion-rich samples. The chondrite-normalized PGE patterns of lherzolite-harzburgite and olivine-dunite have negative

关键词：铬铁矿沉淀蛇绿岩复合物东南沙漠埃及岩石学

Geologic relationships and mineralization of peralkaline/alkaline granite-syenite of the Zargat Na’am ring complex, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2006年第2期25卷 97-111页

作者： Gehad m. saleh Nuclear materials Authority P.O. Box: 530 EL Maadi Cairo Egypt

The Zargat Na’am ring complex crops out 90 km NW of Shalatin City in the Southeastern Desert of Egypt. The ring complex forms a prominent ridge standing high above the surrounding mafic-ultramafic hills. It is cut by two sets of joints and faults which strike predominantly NNW-SSE and E-W, and is injected by dikes, porphyritic alkaline syenites, and felsite porphyries. It consists of alkali syenites, alkali quartz syenites, and peralkaline arfvedsonite-bearing granitic and pegmatitic dikes and sills. The complex is characterized locally by extreme enrichments in REEs, wolframite and rare, high field strength metals (HFSm), such as Zr and Nb. The highest concentrations ({1.5} wt% Zr, {0.25} wt% Nb, {0.6} wt% ∑REEs) occur in aegirine-albite aplites that formed around arfvedsonite pegmatites. Quartz-hosted melt inclusions in arfvedsonite granite and pegmatite provide unequivocal evidence that the peralkaline compositions and rare metal enrichments are primary magmatic features. Glass inclusions in quartz crystals also have high concentrations of incompatible trace elements including Nb (750×10+{-6}), Zr (2500×10+{-6}) and REEs (1450×10+{-6}). The REEs, Nb and Zr compositions of the aegirine-albite aplites plot along the same linear enrichment trends as the melt inclusions, and Y/Ho ratios mostly display unfractionated, near-chondritic values. The chemical and textural features of the aegirine-albite aplites are apparently resultant from rapid crystallization after volatile loss from a residual peralkaline granitic melt similar in composition to the melt inclusions.

关键词：花岗岩埃及矿化作用地质条件

Geology and rare-earth element geochemistry of highly evolved, molybdenite-bearing granitic plutons, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2007年第4期26卷 333-344页

作者： Gehad m. saleh Nuclear materials Authority P.O.Box: 530 El Maadi Egypt

The field relations, mineralogy, and major and trace elements (including REE analyses of whole-rock samples and minerals) of granites and their associated molybdenite + uranium mineralized aplites in Southeastern Desert, Egypt, have been studied. The granites are leucocratic and mostly peraluminous in nature with muscovite increasing at the expense of biotite. The chemical and mineralogical characteristics of the granitic rocks indicate that their melts originated from the LILE-enriched mantle wedge by partial melting and are contaminated by crustal melts, followed by thermogravitational processes. Leucogranites with higher Na2O/K2O ratios from Um Dargag and Um maiat crystallized under H2O-saturated equilibrium conditions in which the exsolved vapor continuously migrated away. The REE patterns of the granites studied are characterized by LREE enrichments and negative Eu anomalies. In comparison, the potassic aplites and the more sodic leucogranites are depleted in LREE, enriched in HREE and show more remarkable negative Eu anomalies. Allanite and monazite are the most important REE carriers in the granites. These minerals are strongly enriched in LREE, whereas fluorite and xenotime, which are more abundant in the aplites, are enriched in HREE. The average Lu/Ce ratio represents the fractionation trend with respect to HREE. It is 0.71 for radioactive fluorite, and it increases to 1.22 for non-radioactive fluorite. The high REE contents of molybdenite represent re-deposition of the mobilized mo and REE. Due to the strong control of accessory minerals, the REEs are of limited use in petrogenetic modelling of highly evolved granitic systems.

关键词：辉钼矿稀土资源褐帘石独居石西南地区沙漠地带埃及

Rare metal-bearing pegmatites from the Southeastern Desert of Egypt:Geology,geochemical characteristics,and petrogenesis

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Chinese Journal Of Geochemistry 2007年第1期26卷 8-22页

作者： Gehad m.saleh Nuclear materials Authority P.O.Box:530 El-MaadiCairoEgypt

The pegmatite province of the Southeastern Desert (SED) is part of a pegmatite district that extends from Egypt (extends to 1200 km2). Rare metal pegmatites are divided into (1) unzoned, Sn-mineralized; (2) zoned Li, Nb, Ta and Be-bearing; and (3) pegmatites and pegmatites containing colored, gem-quality tourmaline. The Rb/Sr data reflect a crustal origin for the rare metal pegmatites and indicate that the original SED magma was generated during the peak of regional metamorphism and predates the intrusion of post-tectonic leucogranites. These bodies developed an early border zone consisting of coarse to very coarse muscovite+quartz+alkali feldspar, followed by an intermediate zone of dominant quartz+feldspar+muscovite rock. Garnet, tourmaline, beryl, galena, pyrite, amblygonite, apatite and monazite are rare accessories in both zones. Cassiterite tends to concentrate in replacement zones and along fractures in albite+quartz+muscovite-rich portions. The highest concentrations of cassiterite occur in irregular greisenized zones which consist dominantly of micaceous aggregates of green Li-rich muscovite, quartz, albite and coarse-grained cassiterite. The different metasomatic post-solidification alterations include sodic and potassic metasomatism, greisenization and tourmalinization. Geochemically, the pegmatite-generating granites have a metaluminous composition, showing a differentiation trend from coarse-grained, unfractionated plagioclase-rich granite towards highly fractionated fine- to medium-grained, local albite-rich rock. Economically important ore minerals introduced by volatile-rich, rare metal-bearing fluids, either primarily or during the breakdown of the primary mineral assemblages, are niobium-tantalum oxides, Sn-oxides (cassiterite), Li-silicates (petalite, spodumene, euctyptite, and pollucite), Li-phosphates (amblygonite, montebrasite and lithopilite) and minor REE-minerals (Hf-zircon, monazite, xenotime, thorian, loparite and yttrio-fluorite). The pol

关键词：埃及东南部沙漠稀有金属伟晶岩地质地球化学特征岩石成因

URANIUm mINERALIZATION IN THE mUSCOVITE-RICH GRANITES OF THE SHALATIN REGION, SOUTHEASTERN DESERT, EGYPT

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Chinese Journal Of Geochemistry 2006年第1期25卷 1-15页

作者： GEHAD m. saleh NUCLEAR mATERIALS AUTHORITY P.O.BOX: 530 EL MAADI CAIRO EGYPT

The younger granitoids of the Shalatin district in the Southeastern Desert of Egypt, are of biotite and two-mica granite compositions. The geochemistry of rare-earth elements (REE), yttrium, thorium and uranium forms the basis for many important methods to reconstruct igneous petrogenesis. Since the recognition that REE, Y, Th, U-rich accessories may play an important role in controlling the geochemistry of crustal melts, a considerable amount of work has been done in an attempt to understand their effects. However, this effort has been almost exclusively focused on three minerals: zircon, monazite and apatite. Nevertheless, the variety of REE-Th-U-rich accessories in granite rocks are neither limited to these three minerals nor are they always the main REE, Y, Th carriers. The geochemistry of REE, Y, Th and U reflects the behavior of accessories and some key major minerals such as garnet and feldspars, and may therefore give valuable information about the conditions of partial melting, melt segregation and crystallization of granite magmas in different crustal regimes. The geochemistry of U and Th during magmatic differentiation has been studied in many granites from different areas and it has been known that the U and Th contents of granitic rocks generally increase during differentiation, although in some cases they decrease. The Th/U ratio can either increase or decrease, depending on redox conditions, the volatile content or alteration by endogene or supergene solutions. The accessory assemblage of muscovite-rich granites and high-grade rocks is composed of monazite, xenotime, apatite, Th-orthosilicate, secondary U-mineralization and betafite-pyrochlore. REE, Y, Th and U are not suitable for geochemical modeling of granitoids by means of equilibrium-based trace element fractionation equations, but are still useful petrogenetic tools.

关键词：铀矿化作用稀土元素花岗岩沙漠埃及

The Odd Log-Logistic Weibull-G Family of Distributions with Regression and Financial Risk models

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Journal of the Operations Research Society of China 2022年第1期10卷 133-158页

作者： mahdi Rasekhi Emrah Altun morad Alizadeh haitham m.Yousof Department of Statistics Malayer UniversityMalayerIran Department of mathematics Bartin UniversityBartinTurkey Department of Statistics Persian Gulf UniversityBushehrIran Department of Statistics Mathematics and InsuranceBenha UniversityBenhaEgypt

A new generalization of the Weibull-G family is proposed with two extra shape param*** mathematical properties are derived in great *** the Weibull and normal distributions as baseline distributions,two models are *** first model is a location-scale regression model based on a new extension of the Weibull *** second model is a new two-step financial risk model to forecast the daily value at *** flexibility and applicability of the proposed models are investigated by means of five real data sets on the lifetime and financial *** findings of the study show that proposed models work well and produce better results than other well-known models for financial risk modeling and censored lifetime data analysis.

关键词： Odd log-logistic-G family Weibull-G family Regression model Value at risk Simulation maximum likelihood Financial risk modeling

Personality Assessment Based on Natural Stream of Thoughts Empowered with machine Learning

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Computers, materials & Continua 2023年第7期76卷 1-17页

作者： mohammed Salahat Liaqat Ali Taher m.Ghazal haitham m.Alzoubi College of Engineering and Technology University of Science and Technology of FujairahFujairahUAE School of Information Technology Skyline University CollegeUniversity City Sharjah1797UAE Center for Cyber Security Faculty of Information Science and TechnologyUniversiti Kebangsaan Malaysia(UKM)43600Malaysia School of Business Skyline University CollegeUniversity City Sharjah1797SharjahUAE

Knowing each other is obligatory in a multi-agent collaborative *** may develop the desired know-how of each other in various aspects such as habits,job roles,status,and *** different distinguishing characteristics related to a person,personality traits are an effective predictive tool for an individual’s behavioral *** has been observed that when people are asked to share their details through questionnaires,they intentionally or unintentionally become *** knowingly or unknowingly provide enough information in much-unbiased comportment in open writing about *** writings can effectively assess an individual’s personality traits that may yield enormous possibilities for applications such as forensic departments,job interviews,mental health diagnoses,*** of consciousness,collected by James Pennbaker and Laura King,is one such way of writing,referring to a narrative technique where the emotions and thoughts of the writer are presented in a way that brings the reader to the fluid through the mental states of the ***-over,computationally,various attempts have been made in an individual’s personality traits assessment through deep learning algorithms;however,the effectiveness and reliability of results vary with varying word embedding *** article proposes an empirical approach to assessing personality by applying convolutional networks to text *** Encoder Representations from Transformers(BERT)word embedding technique is used for word vector generation to enhance the contextual meanings.

关键词： Personality traits convolutional neural network deep learning word embedding

Blockchain for secure and decentralized artificial intelligence in cybersecurity: A comprehensive review

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Blockchain(Research and Applications) 2024年第3期5卷 184-208页

作者： Ahmed m.Shamsan saleh Department of Information Technology University of TabukTabuk47512Saudi Arabia

As the use of artificial intelligence (AI) grows within the field of cybersecurity, so does the demand for secure and decentralized AI systems to protect against potential cyber threats. Blockchain technology has emerged as the ideal approach for increasing both the security and privacy of AI systems since it provides decentralized and immutable data storage. This systematic literature review focuses on the integration of blockchain technology with decentralized AI within cybersecurity. It provides a comprehensive taxonomy of blockchain technology and decentralized AI for cybersecurity, serving as the starting point for the study. This paper begins with an overview of blockchain technology and its possible uses in cybersecurity and also analyzes its challenges and opportunities. Decentralized AI is also covered in the study, along with its potential advantages and difficulties in decentralized AI cybersecurity. Building on that foundation, this study provides convincing findings highlighting the beneficial relationships between blockchain technology and decentralized AI for cybersecurity, contributing to a nuanced comprehension of their integration. moreover, it offers real-world uses of blockchain-enabled, decentralized AI to discuss its usefulness in tackling cybersecurity concerns. Finally, this paper discusses future research directions for blockchain-enabled decentralized AI in cybersecurity, including potential applications and implications of this technology in the field, emphasizing the potential of blockchain-enabled decentralized AI in cybersecurity to enhance security, privacy, and trust in AI systems.

关键词： Blockchain Artificial intelligence Decentralized Cybersecurity