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National science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David M.Bell Tiantian Wang houssni Lamkaddam Tianqu Cui Lu Qi Mihnea surdu Dongyu Wang Lin Du Imad El haddad Jay G.slowik Andre s.h.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(sOAs). Previous smog chamber studies found that the sOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient sOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to sOA formation has not been directly observed. here, by deploying a newly-developed oxidation flow reactor to study sOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed sOA, i.e.>2 times more than VOCs. This previously missing sOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that sOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

一株柠檬内生细菌Z10的分离鉴定及其抑菌活性的发酵条件优化

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微生物学通报 2024年第5期51卷 1641-1658页

作者：钱程叶景 Khadija ei Galai 张琴高梦蝶杨新宇喻艳玲唐松安徽工程大学生物与食品工程学院安徽芜湖241000

【背景】近年来,从植物内生菌的发酵产物中挖掘抑菌活性成分已成为寻找新型生物活性成分的重要途径。【目的】寻找新的具有高效抗菌活性的植物内生菌,并探究其产生抗菌活性物质的最优发酵条件和抑菌机制。【方法】利用组织分离法和划线... 详细信息

【背景】近年来,从植物内生菌的发酵产物中挖掘抑菌活性成分已成为寻找新型生物活性成分的重要途径。【目的】寻找新的具有高效抗菌活性的植物内生菌,并探究其产生抗菌活性物质的最优发酵条件和抑菌机制。【方法】利用组织分离法和划线法从柠檬皮和籽核中分离内生菌株,按照滤纸片和牛津杯法筛选对病原菌具有较强抑制作用的菌株,通过形态观察和16s rRNA基因序列分析确定活性菌株的分类地位,基于微孔板法检测活性菌株发酵液提取液(B02c)的抑菌效果,以单因素试验和响应面试验设计对发酵条件进行优化,并通过碘化丙啶/sYTO-9探针标记结合流式细胞术检测B02c对检定菌细胞膜的影响。【结果】从柠檬籽核中筛选出一株对金黄色葡萄球菌(staphylococcus aureus)具有显著抑制作用的菌株Z10,鉴定为芽孢杆菌(Bacillus sp.);菌株Z10的最佳发酵条件为柑橘皮渣添加量1.6 g/100 mL、ph 6.8、接种量10.0%、转速172 r/min、培养时间36 h,优化后B02c的抑菌率达到84.36%,较优化前提升16.36%;B02c对金黄色葡萄球菌的最低抑制浓度(minimum inhibitory concentration,MIC)为3.125 mg/mL,其能够破坏金黄色葡萄球菌细胞膜的完整性。【结论】柠檬内生菌Z10在优化发酵条件后获得的B02c对金黄色葡萄球菌具有良好的抑菌效果,在新型、高效的天然抑菌活性物质筛选及其工业化生产中具有一定应用前景。

关键词：分离鉴定芽孢杆菌内生菌抑菌机制发酵优化

Therapeutic Effect of Dimethyl Dimethoxy Biphenyl Dicarboxylate on Collagen-Induced Arthritis in Rats

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Chinese Journal of Integrative Medicine 2015年第11期21卷 846-854页

作者： Roba M Talaat Amira s Abo-ei-Atta sabah M Farou Karima I ei-Dosoky Molecular Biology Department Genetic Engineering and Biotechnology Research InstituteMenofia UniversitySadat Branch Pathology Department Faculty of MedicineTanta University

Objective： To study the effect of oral administration of dimethyl dimethoxy biphenyl dicarboxylate （DDB） on adjusting angiogeneic/inflammatory mediators and ameliorating the pathology of bones in rats with collagen-induced arthritis （CIA）. Methods： Wistar rat model of CIA was set up using bovine collagen type h. Fifty rats were divided into five groups randomly： normal, CIA model, DDB treatment, methotrexate （MTX） treatment, and combined DDB＋MTX treatment. Ankle joints of rats were imaged with digital X-ray machine to show the destruction of joints. Fore and hind paw and knee joints were removed above the ankle joint then processed for haematoxylin and eosin staining. Plasma levels of vascular endothelial growth factor （VEGF）, platelet derived growth factor, interleukin-8 （IL-8）, IL-4, tumor necrosis factor α （TNF-α）, and cyclooxygenase-2 （COX-2） were quantified by enzyme-linked immunosorbent assay. Nitric oxide levels were detected by Griess reagent. Results： Compared with the CIA model group, a remarkable reduction in various angiogenic （VEGF and IL-8） and inflammatory mediators （TNF-α, IL-4 and COX-2） after treatment with DDB either alone or combined with MTX （P〈0.05 or P〈0.01）. histopathological and X-ray findings were confirmatory to the observed DDB anti-arthritic effect. The DDB-treated group showed amelioration in signs of arthritis which appeared essentially similar to normal. Conclusion： Our data shed light on the therapeutic efficacy of DDB in experimental rheumatoid arthritis （RA） compared with a choice drug （MTX） and it may be offered as a second-line drug in the treatment of RA.

关键词： rheumatoid arthritis collagen-induced arthritis dimethyl dimethoxy biphenyl dicarboxylate angiogenesis inflammation

Preparation, Characterization, Biological Activity and 3D Molecular Modeling of Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） Complexes of some sulfadrug schiff Bases

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Chinese Journal of Chemistry 2012年第4期30卷 881-890页

作者： EL-Ghamry,h.A. sakai,K. Masaoka,s. ei-Baradie,K.Y Issa,R.M. Chemistry Department Faculty of ScienceTanta UniversityTantaEgypt Chemistry Department Faculty of ScienceKyushu UniversityFukuokaJapan Institute for Molecular science National Institutes of Natural SciencesJapan

Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） complexes of schiff bases derived from the condensation of sulfaguanidine with 2,4-dihydroxy benzaldehyde （hL1）, 2-hydroxy-l-naphthaldehyde （hL2） and salicylaldehyde （hL3） have been synthesized. The structures of the prepared metal complexes were proposed based on elemental analysis, molar conductance, thermal analysis （TGA, DsC and DTG）, magnetic susceptibility measurements and spectroscopic techniques （IR, UV-Vis, and EsR）. In all complexes, the ligand bonds to the metal ion through the azomethine nitrogen and a-hydroxy oxygen atoms. The structures of Pd（Ⅱ） complex 8 and Ru（Ⅲ） complex 9 were found to be polynuclear. Two kinds of stereochemical geometries; distorted tetrahedral and distorted square py- ramidal, have been realized for the Cu（Ⅱ） complexes based on the results of UV-Vis, magnetic susceptibility and EsR spectra whereas octahedral geometry was predicted for Co（Ⅱ）, Mn（Ⅱ） and Ru（Ⅲ） complexes. Ni（Ⅱ） com- plexes were predicted to be square planar and tetrahedral and Pd（Ⅱ） complexes were found to be square planar. The antimicrobial activity of the ligands and their metal complexes was also investigated against the gram-positive bac- teria staphylococcus aures and Bacillus subtilis and gram-negative bacteria, Escherichia coli and Pesudomonas aeruginosa, by using the agar dilution method. Chloramphenicol was used as standard compound. The obtained data revealed that the metal complexes are more or less, active than the parent ligand and standard. The X-ray crys- tal structure of hL3 has been also reported.

关键词： sulfaguanidine transition metal complexes spectral studies biological activity crystal structure mo- lecular modeling

Oxidative leaching kinetics of molybdenum-uranium ore in h2sO4 using h2O2 as an oxidizing agent

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Frontiers of Chemical science and Engineering 2013年第1期7卷 95-102页

作者： T. A. Lasheen M. E. ei-Ahmady h. B. hassib A. s. helal Nuclear Materials Authority Cairo Egypt Chemistry Department Faculty of Science Cairo University Giza Egypt

The processing of molybdenum-uranium ore in a sulfuric acid solution using hydrogen peroxide as an oxidant has been investigated. The leaching temperature, hydrogen peroxide concentration, sulfuric acid concentration, leaching time, particle size, liquid-to-solid ratio and agitation speed all have significant effects on the process. The optimum process operating parameters were： temperature： 95℃; h2O2 concentration： 0.5 M; sulfuric acid concentration： 2.5 M; time： 2 h; particle size： 74 gm, liquid-to-solid ratio： 14 ： 1 and agitation speed： 600 rpm. Under these experimental conditions, the extraction efficiency of molybdenum was about 98.4%, and the uranium extraction efficiency was about 98.7%. The leaching kinetics of molybdenum showed that the reaction rate of the leaching process is controlled by the chemical reaction at the particle surface. The leaching process follows the kinetic model 1 - （1-X）1/3 = kt with an apparent activation energy of 40.40 kJ/mole. The temperature, concentrations of h202 and h2sO4 and the mesh size are the main factors that influence the leaching rate. The reaction order in h2sO4 was 1.0012 and in h202 it was 1.2544.

关键词： leaching of molybdenum leaching of uranium kinetics

Antibody to El peptide of hepatitis C virus genotype 4 inhibits virus binding and entry to hepG2 cells in vitro

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World Journal of Gastroenterology 2006年第16期12卷 2530-2535页

作者： Mostafa K EL-Awady Ashraf A Tabll Khaled Atef samar s Yousef Moataza h Omran Yasmin ei-Abd Noha G Bader-Eldin Ahmad M salem samir F Zohny Wael T ei-Garf Department of Biomedical Technology National Research CenterCairoEgypt Department of Biochemistry Faculty of ScienceAin Shams UniversityCairoEgypt

AIM： To analyze the neutralizing activity of antibodies against E1 region of hepatitis C virus （hCV）. specific polydonal antibody was raised via immunization of New Zealand rabbits with a synthetic peptide that had been derived from the E1 region of hCV and was shown to be highly conserved among hCV published genotypes. METhODs： hyper-immune hCV E1 antibodies were incubated over night at 4 ℃ with serum samples positive for hCV RNA, with viral loads ranging from 615 to 3.2 million IU/mL. Treated sera were incubated with hepG2 cells for 90 min. Blocking of viral binding and entry into cells by anti E1 antibody were tested by means of RTPCR and flow cytometry. REsULTs： Direct immunostaining using FITC conjugated E1 antibody followed by Flow cytometric analysis showed reduced mean fluorescence intensity in samples pre-incubated with E1 antibody compared with untreated samples. Furthermore, 13 out of 18 positive sera （72%） showed complete inhibition of infectivity as detected by RT-PCR. CONCLUsION： In house produced E1 antibody, blocks binding and entry of hCV virion infection to target cells suggesting the involvement of this epitope in virus binding and entry. Isolation of these antibodies that block virus attachment to human cells are useful as therapeutic reagents.

关键词： Flow cytometry hepatitis C virus E1 envelope Therapeutic antibodies Direct immuno-fluorescence hepG2 cells

Folded novel accurate analytical and semi-analytical solutions of a generalized Calogero–Bogoyavlenskii–schiff equation

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Communications in Theoretical Physics 2021年第9期73卷 26-36页

作者： Mostafa M A Khater s K Elagan M A El-shorbagy s h Alfalqi J F Alzaidi Nawal A Alshehri Department of Mathematics Faculty of ScienceJiangsu University212013ZhenjiangChina Department of Mathematics Obour High Institute For Engineering and Technology11828CairoEgypt Department of Mathematics Faculty of ScienceTaif University P.O.Box 11099Taif 21944Saudi Arabia Department of Mathematics College of Science and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of Basic Engineering science Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt Department of Mathematics Faculty of Science and ArtsMahayil Asir King Khalid UniversityAbhaSaudi Arabia

This paper studies the analytical and semi-analytic solutions of the generalized Calogero–Bogoyavlenskii–schiff(CBs)*** model describes the(2+1)–dimensional interaction between Riemann-wave propagation along the y-axis and the x-axis *** extended simplest equation(EsE)method is applied to the model,and a variety of novel solitarywave solutions is *** solitary-wave solutions prove the dynamic behavior of soliton waves in *** accuracy of the obtained solution is verified using a variational iteration(VI)semi-analytical *** analysis and the match between the constructed analytical solution and the semi-analytical solution are sketched using various diagrams to show the accuracy of the solution we *** adopted scheme’s performance shows the effectiveness of the method and its ability to be applied to various nonlinear evolution equations.

关键词： generalized Calogero-Bogoyavlenskii-schiff equation accurate analytical semianalytical solutions

Low-temperature alteration of uranium–thorium bearing minerals and its significance in neoformation of radioactive minerals in stream sediments of Wadi El-Reddah, North Eastern Desert, Egypt

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Acta Geochimica 2020年第1期39卷 96-115页

作者： O.A.Ebyan h.A.Khamis A.R.Baghdady M.G.El-Feky N.s.Abed Geology Department Faculty of ScienceAin Shams UniversityCairo 11566Egypt Nuclear Materials Authority(NMA) P.O.Box 530El-MaadiCairoEgypt

The stream sediments of Wadi El Reddah(North Eastern Desert,Egypt)are geochemically and mineralogically *** content of radioactive and other heavy minerals is mainly represented by thorite,uranothorite,zircon,monazite,xenotime,columbite,fergusonite,and unknown rare earth elements(REEs)bearing minerals as well as *** emphasis on REE content of thorite,uranothorite,zircon and xenotime has been done to correlate them with the increase of uranium contents in these *** key evidence for the presence lowtemperature alteration processes includes the presence of some zircon crystals as remnants after complete dissolution of the overgrowth zircon in severe acidic environment,the sulphur content,biogenic minerals,occurrence of unusual minerals as cassiterite pore filling in zircon,variation in the REEs content from the surrounding granites to the stream sediments and the abundance of monazite in the surrounding *** minerals are partially and/or completely altered,which indicated by the pseudomorphism of zircon by xenotime,thorite,and uranothorite.

关键词： Zircon Thorite Xenotime Radioactive minerals Low-temperature alteration Wadi El-Reddah

synthesis of Novel 3-substituted PyridothienopyrimidineDerivatives with Biological Evaluation as Antimicrobial Agents

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Chemical Research in Chinese Universities 2016年第6期32卷 967-972页

作者： Farag A. E1-Essawy Nader M. Boshta Ayman K. ei-sawaf Areal A. Nassar Mohamed s. Khalafalah Preparatory Year Deanship Basic Science Department Prince Sattam Bin Abdulaziz University KSA Chemistry Department Faculty of Science Menoufia University Shebin EI-Koam Egypt Collage of science and humanitles Prince Sattam Bin Abdulaziz University KSA Faculty of Education for Girls Prince Sattam Bin Abdulaziz University KSA

Novel 3-substituted pyridothienopyrimidine derivatives have been synthesized via the reaction of 2-{7,9-dimethyl-4-oxopyrido[3′,2′：4,5]thieno[3,2-d]pyrimidin-3（4h）-yl}acetohydrazide（5） with a variety of activereagents and chemicals. structures of the newly synthesized compounds were established based on spectral *** resulting pyridothienopyrimidine derivatives were evaluated for their possible antimicrobial activity and some ofthem represent a new class of potentially antimicrobial compounds, especially compounds 9 and 18 which displayedthe highest activity against Gram-positive bacteria, Gram-negative bacteria, and Fungi in MIC range of 0.12--1.95 μg/mL.

关键词： Nitrogen-containing heterocycle Pyridothienopyrimidine Thieno[2,3-b]pyridine Antimicrobial

hydrogen storage of Mgi-xMxh2 （M--Ti, V, studied using first-principles calculations re）

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Chinese Physics B 2012年第9期21卷 477-483页

作者： M.Bhihi M.Lakhal h.Labrim A. Benyoussefa A.ei Kenz O.Mounkachi E.K.hlil Laboratoire de Magnetisme et de Physique des hautes Energies associe au CNRST (URAC 12) Departement de PhysiqueB.P. 1014 Faculte des Sciences Universite Mohammed V-Agdal Rabat Morocco National Centre for Energy Sciences and Nuclear Techniques ONESTEN Morocco Institute of Nanomaterials and Nanotechnologies MACslR Rabat Morocco hassan II Academy of science and Technology Rabat Morocco Institut N6el CNRS-UJF 38042 Grenoble Cedex 9 France

In this work, the hydrogen storage properties of the Mg-based hydrides, i.e., Mgl-xMxh2 （M=Ti, V, Fe, 0≤ x ≤ 0.1）, are studied using the Korringa-Kohn-Rostoker （KKR） calculation with the coherent potential approximation （CPA） . In particular, the nature and concentrations of the alloying elements and their effects are studied. Moreover, the material＇s stability and hydrogen storage thermodynamic properties are discussed. In particular, we find that the stability and the temperature of desorption decrease without significantly affecting the storage capacities.

关键词： first-principles calculation formation energy electronic structure hydrogen storage