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Dynamics of CO_2 Emission and Biochemical Properties of a Sandy Calcareous Soil Amended with Conocarpus Waste and Biochar

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Pedosphere 2015年第1期25卷 46-56页

作者： mohamed el-MAHROUKY Ahmed Hamdy el-NAGGAR Adel Rabie USMAN Mohammad Al-WABel Soil Science Department College of Food & Agriculture Sciences King Saud University Department of Soil Science Faculty of Agriculture Ain Shams University Department of Soils and Water Faculty of Agriculture Assiut University

Biochar is a carbon-rich product obtained by biomass pyrolysis and considered a mean of carbon sequestration. In this research, a sandy calcareous soil from the Farm of the College of Food & Agriculture Sciences, King Saud University, Saudi Arabia, was amended with either woody waste of Conocarpus erectus L.(CW) or the biochar(BC) produced from CW at rates of 0(control), 10, 30 and 50 g kg-1. The effects of the amendments on soil p H, dissolved organic carbon(DOC), microbial biomass carbon(MBC), CO2 emission and metabolic quotient(q CO2) of the sandy calcareous soil were studied in a 60-d incubation experiment. The results showed that the addition of CW led to a significant decrease in soil p H compared to the control and the addition of BC. The CO2-C emission rate was higher in the first few days of incubation than when the incubation time progressed. The cumulative CO2-C emission from the soil amended with CW, especially at higher rates, was higher(approximately 3- to 6-fold) than that from the control and the soil amended with BC. The BC-amended soil showed significant increases in CO2-C emission rate during the first days of incubation as compared to the non-amended soil, but the increase in cumulative CO2-C emission was not significant after 60 d of incubation. On the other hand, CW applications resulted in considerably higher cumulative CO2-C emission, MBC and DOC than the control and BC applications. With the exception of 0 day(after 1 h of incubation), both CW and BC applications led to lower values of q CO2 as compared to the control. The power function kinetic model satisfactorily described the cumulative CO2-C emission. Generally, the lowest values of CO2 emission were observed in the soil with BC, suggesting that the contribution of BC to CO2 emission was very small as compared to that of CW.

关键词： dissolved organic carbon metabolic quotient microbial biomass carbon power function kinetic model soil pH

Review on friction stir welding of dissimilar magnesium and aluminum alloys: Scientometric analysis and strategies for achieving high-quality joints

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Journal of Magnesium and Alloys 2023年第11期11卷 4082-4127页

作者： mohamed M.Z.Ahmed mohamed M.el-Sayed Seleman Dariusz Fydrych Gürel ÇAM Department of Mechanical Engineering College of Engineering at Al KharjPrince Sattam Bin Abdulaziz UniversityAl Kharj 11942Saudi Arabia Department of Metallurgical and Materials Engineering Faculty of Petroleum and Mining EngineeringSuez UniversitySuez 43512Egypt Faculty of Mechanical Engineering and Ship Technology Institute of Machines and Materials TechnologyGdańsk University of TechnologyGabriela Narutowicza Street 11/12Gdańsk 80-233Poland Department of Mechanical Engineering Iskenderun Technical UniversityIskenderunHatay 31200Turkiye

Magnesium and aluminum alloys continually attract interest as lightweight structural materials for transport applications. However, joining these dissimilar alloys is very challenging. The main obstacle that hinders progress in dissimilar Mg-Al joining is the formation of brittle intermetallic compounds(IMCs). As a solid-state joining technique, FSW is an excellent candidate to attenuate the deleterious IMC effects in dissimilar Al-Mg joining due to the inherent low heat inputs involved in the process. However, the IMCs, namely Al_(3)Mg_(2) and Al_(12)Mg_(17) phases, have also been reported to form during Al-Mg dissimilar FSW;their amount and thickness depend on the heat input involved;thus,the weld parameters used. Since the heat dissipated in the material during the welding process significantly affects the amount of IMCs,the heat input during FSW should be kept as low as possible to control and reduce the amount of IMCs. This review aims to critically discuss and evaluate the studies conducted in the dissimilar Al/Mg FSW through a scientometric analysis and also with a focus on the strategies recently applied to enhance joint quality. The scientometric analysis showed that the main research directions in Mg/Al FSW are the technological weldability of aluminum and magnesium during FSW, structural morphology, and mechanical properties of dissimilar welded joints. Considering the scope of application of the aforementioned joints, the low share of articles dealing with environmental degradation and operational cracking is surprising. This might be attributed to the need for well-developed strategies for obtaining high-quality and sustainable joints for applications. Thus, the second part of this review is conventional, focusing mainly on the new strategies for obtaining high-quality Mg/Al joints. It can be concluded that in addition to the necessity to optimum welding parameters to suppress the excessive heat to limit the amount and thickness of IMC formed and improv

关键词： Friction stir welding(FSW) Al-alloys Mg-alloys Dissimilar material welding Intermetallics Weld performance

Dolomite apatite separation by amphoteric collector in presence of bacteria

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Journal of Central South University 2013年第6期20卷 1645-1652页

作者： elmahdy Ahmed el-Mofty Salah Abdel-Khalek mohamed Abdel-Khalek Nagui el-MidanyAyman Central Metallurgical Research and Development Institute Mining Petroleum and Metallurgical Engineering DepartmentCairo University

Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the MgO to less than 1%. A phosphate content of 0.7% MgO and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.

关键词： dolomite phosphate amphoteric collector bacteria bio-flotation carbonate minerals

Epigenetic regulation of insulin-like growth factor axis in hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第9期22卷 2668-2677页

作者： Hend mohamed el Tayebi Ahmed Ihab Abdelaziz The Molecular Pathology Research Group Department of Pharmacology and Toxicology Faculty of Pharmacy and Biotechnology German University in Cairo

The insulin-like growth factor(IGF) signaling path-way is an important pathway in the process of hepa-tocarcinogenesis,and the IGF network is clearly dysregulated in many cancers and developmental *** hepatocellular carcinoma(HCC),only a minority of patients are eligible for curative treatments,such as tumor resection or liver ***,there is a high recurrence of HCC after surgical tumor *** research efforts have focused on targeting IGF axis members in an attempt to find therapeutic options for many health *** this review,we shed lights on the regulation of members of the IGF axis,mainly by micro RNAs in *** RNAs in HCC attempt to halt the aberrant expression of the IGF network,and a single micro RNA can have multiple downstream targets in one or more signaling *** micro RNAs is a relatively new approach for identifying an efficient radical cure for HCC.

关键词： Hepatocellular carcinoma Insulin-like growth factors Insulin-like growth factor receptors Epigenetics microRNAs

A Novel Approach in Hydrogeochemical Exploration for Uranium Mineralization:an Example from West Central Sinai,Egypt

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Acta Geologica Sinica(English Edition) 2015年第6期89卷 1895-1913页

作者： Ahmed E.el-RAYES mohamed O.ARNOUS Suez Canal University Faculty of SciencesGeology Department

Groundwater in contact with ore deposits may acquire a chemical composition that could be used as a guide for exploration. Eight well-water samples are collected from a known uraniummineralized area near Abu Zenima, west central Sinai to examine the applicability of using the hydrogeochemical technique in the search for uranium mineralization in similar arid areas. The analytical chemical data of the ground water is compared with ground radiometric measurements. The obtained results indicate that groundwater affected by uranium mineralization has a specific relativity of major anions expressed essentially as SO_4〉Cl〉HCO_3 and to a lesser extent as Cl〉SO_4〉HCO_3, associated as a rule with low magnesium content. This association constitutes a signature of uranium mineralization on the composition of groundwater in west central Sinai and could be used as an important exploration guide in the search for uranium deposits in similar areas. Anomalies in Ni, Fe, Zn and Cr and other pathfinder elements in groundwater can furnish geochemical guides to uranium ores. The immobile trace element anomalies, including Zn, Ni and Fe are strongly distributed near the orebody; whereas the relatively mobile trace elements, including Co, U, V and Cr, constitute the dispersion haloes away from the orebody. A new hydrogeochemical discrimination diagram is constructed to be used as a quick and cost effective exploration tool in the search for uranium occurrences in environmentally similar arid areas. Based on the obtained results, a new site for uranium occurrence, west of W. Baba, is delineated and recommended for future detailed geological and geochemical surveying.

关键词： Hydrogeochemical exploration Uranium ores geospatial mapping graphical explorationtool remote sensing Sinai

Micro-fabrication of ceramics:Additive manufacturing and conventional technologies

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Journal of Advanced Ceramics 2021年第1期10卷 1-27页

作者： Hany HASSANIN Khamis ESSA Amr elSHAER mohamed IMBABY Heba H.el-MONGY Tamer A.el-SAYED School of Engineering Canterbury Christ Church UniversityCanterburyCT11QUUK University of Birmingham EdgbastonB152TTUK Kingston University London Penrhyn RoadKingston Upon ThamesSurreyKT12EEUK Department of Mechanical Design Faculty of EngineeringMatariaHelwan UniversityP.O.Box.11718CairoEgypt Jubail University College Mechanical EngineeringKingdom of Saudi Arabia Center for Applied Dynamics Research(CADR) School of EngineeringUniversity of AberdeenAberdeenAB243UEUK

Ceramic materials are increasingly used in micro-electro-mechanical systems(MEMS)as they offer many advantages such as high-temperature resistance,high wear resistance,low density,and favourable mechanical and chemical properties at elevated ***,with the emerging of additive manufacturing,the use of ceramics for functional and structural MEMS raises new opportunities and *** paper provides an extensive review of the manufacturing processes used for ceramic-based MEMS,including additive and conventional manufacturing *** review covers the micro-fabrication techniques of ceramics with the focus on their operating principles,main features,and processed *** that need to be addressed in applying additive technologies in MEMS include ceramic printing on wafers,post-processing at the micro-level,resolution,and quality *** paper also sheds light on the new possibilities of ceramic additive micro-fabrication and their potential applications,which indicates a promising future.

关键词： micro-electro-mechanical system(MEMS) micro-fabrication ceramics micro parts additive manufacturing

Induction of sub-G0 arrest and apoptosis by seed extract of Moringa peregrina（Forssk.） Fiori in cervical and prostate cancer cell lines

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Journal of Integrative Medicine 2019年第6期17卷 410-422页

作者： Maged mohamed Maher Abou-Hashem Dina mohamed Abo-elmatty Noha Mostafa Mesbah Ahmed mohamed Abd el-Mawgoud Faculty of Pharmacy Pharmacognosy DepartmentZagazig UniversityZagazig 44511Egypt Faculty of Pharmacy Biochemistry DepartmentSuez Canal UniversityIsmailia 41522Egypt Egyptian International Pharmaceuticals Industries Company Tenth of Ramadan City 44629Egypt

Objective: This study investigated cytotoxicity and induction of apoptosis in human cervical cancer cells(HelA) and prostate cancer cells(PC-3) using the most active fraction of Moringa peregrina seed ***: Dried and powdered seeds were extracted using 95% ethanol. The total ethanolic extract was further dissolved in distilled water and separated into petroleum ether, chloroform, ethyl acetate and aqueous extracts. Based on the results of in vitro anticancer studies of all extracts, the most highly active extract was selected for evaluation of apoptosis induction and cell cycle analysis on HelA and PC-3 cells at its half maximal inhibitory concentration using flow cytometry;DNA fragmentation by agarose gel electrophoresis and the expression of protein were measured by Western ***: The chloroform fraction from the ethanolic extract of M. peregrina(CFEE) was the most active antitumor fraction. The selectivity index, determined using the normal Vero cell line, indicated that CFEE had a high degree of selectivity against HelA and PC-3 cells. CFEE induced apoptosis, confirmed by cell cycle arrest at sub-G0 phase and DNA fragmentation. CFEE induced an increase in mRNA expression of caspase-3, a decrease in Bcl-2 mRNA expression, and decreased ATP levels. CFEE increased protein expression of caspase-3 and decreased protein expression of poly-ADP-ribose polymerase-1(PARP-1).Flow cytometric analysis showed an appreciable increase in the number of cells in the early apoptotic stage in CFEE-treated HelA and PC-3 cells. CFEE treatment significantly increased lipid peroxidation(malondialdehyde level) in HelA and PC-3 ***: Seed extract of M. peregrina displayed a significant antitumor effect through apoptosis induction in HelA and PC-3 cells.

关键词： Moringa peregrina Fractionation Antiproliferation Apoptosis

Effect of smart sprinkler irrigation utilization on water use efficiency for wheat crops in arid regions

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 26-35页

作者： Hussein Mohammed Al-Ghobari mohamed Said Abdalla el Marazky Department of Agricultural Engineering College of Food and Agriculture Sciences King Saud UniversityRiyadh 11451Kingdom of Saudi Arabia

The smart irrigation system(SIS)developed in this research is a valuable tool for scheduling irrigation and quantifying water required by *** was implemented and tested under sprinkler irrigation system to irrigate wheat crops(YecoraRojo).Results obtained from this system were compared with the control irrigation system(CIS),whose scheduling method was based on data from an automatic weather *** indicated significant savings in applied water using the *** addition,the use of the SIS conserved 12%of irrigation water compared to CIS and obtained an economical *** water use efficiency(WUE)under SIS had generally higher values(1.64 kg/m^(3))compared to CIS(1.46 kg/m^(3)).Hence,the application of SIS technology provides significant advantages on WUE and irrigation water use efficiency(IWUE).Relatively high WUE and IWUE were found for the irrigation treatment(80%of evapotranspiration under SIS).Results showed that the irrigation requirements of wheat increased(100%of ETc under CIS)with increasing evapotranspiration(ETc)but excessive irrigation could decrease WUE and *** results indicated that extreme irrigation might not produce higher yield or optimal economic benefit,thus,suitable irrigation schedules by using SIS must be established and extendable to other agricultural crops.

关键词： smart irrigation system(SIS) sprinkler irrigation scheduling water use efficiency arid region evapotranspiration grain yield

Amination of biochar surface from watermelon peel for toxic chromium removal enhancement

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Chinese Journal of Chemical Engineering 2021年第8期34卷 199-222页

作者： mohamed A.el-Nemr Ibrahim M.A.Ismail Nabil M.Abdelmonem Ahmed el Nemr Safaa Ragab Department of Chemical Engineering Faculty of EngineeringCairo UniversityGizaEgypt Renewable Energy Program Zewail City of Science and TechnologyEgypt Environmental Division National Institute of Oceanography and FisheriesKayet BeyEl-AnfoushyAlexandriaEgypt

Watermelon peel residues were used to produce a new biochar by dehydration *** new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI)ions from aqueous solution has been *** biochars,Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA,were made from watermelon peel via dehydration with 50%sulfuric acid to give Melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give Melon-BO-NH_(2) or Triethylenetetramine(TETA)to give *** prepared biochars were characterized by BET,BJH,SEM,FT-IR,TGA,DSC and EDAX *** highest removal percentage of Cr(VI)ions was 69%for Melon-B,98%for Melon-BO-NH_(2) and 99%for Melon-BO-TETA biochars of 100 mg·L^(−1) Cr(VI)ions initial concentration and 1.0 g·L^(−1) adsorbents *** unmodified biochar(Melon-B)and modified biochars(Melon-BO-NH_(2) and Melon-BO-TETA)had maximum adsorption capacities(Q_(m))of 72.46,123.46,and 333.33 mg·g^(−1),*** amination of biochar reduced the pore size of modified biochar,whereas the surface area was *** obtained data of isotherm models were tested using different error function *** Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA,*** adsorption rate was primarily controlled by pseudo-second–order rate ***,the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption *** adsorption for the Melon-B,Melon-BO-NH_(2) and Melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction.

关键词： Waste treatment Powder technology Citrullus lanatus Hexavalent chromium Biochar amination Adsorption