检索结果-南通市图书馆

mineralization of ^(14)C-ring Labelled 2,4-D in egyptian Soils Under Aerobic and Anaerobic Conditions

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

Biomedical and environmental Sciences 2002年第4期15卷 306-314页

作者： S．m．A．D．zayed m．FARGHALY 等 NationalReserachCenter DokkiCairoEgypt

Obiectives To study the mineralization of 2,4-D in clay and clay loam egyptian soils under subtropical conditions over a period of 90 d. methods Using 14C-ring labelled pesticide, laboratory studies under aerobic and anaerobic conditions were conducted. 14C-activity in solutions was directly determined by liquid scintillation counting. Unextractable soil residues were determined by combustion. The nature of methanolic '4C-residues was determined by thin layer and high performance liquid chromatographic analysis. Results Under aerobic conditions 10%-14% of applied dose was mineralized during 90 d irrespective of soil type. The soil extractable pesticide residues decreased with time and the bound residues gradually increased. The highest binding capacity of about 26%-29% was observed in clay soil under aerobic conditions after 90 d. A good balance sheet was obtained and the percentage recovery was generally between 91% and 100%. Conclusion The mineralization of 2,4-D in clay soil was higher than that in clay loam soil under anaerobic conditions. Under aerobic conditions, the soil type had no influence on mineralizaion capacity of 2,4-D during 90 d. The soil binding increased with time whereby the extractable 14C-residues simultaneously decreased. Chromatographic analysis of the methanol extractable l4C-residues of soils revealed the presence of 2,4-D as a main product together with 2,4-dichlorophenol.

关键词： 14C-ring labelled Organochlorine pesticide egyptian soil Radiochemicals

ReAL PALeY-WIeNeR THeORemS FOR THe SPACe-TIme FOURIeR TRANSFORm

在线全文

学校读者我要写书评

暂无评论

Acta mathematica Scientia 2023年第3期43卷 1105-1115页

作者： Youssef eL HAOUI mohra zayed ecole Normale Supérieure(eNS-meknès) Moulay Ismail UniversityMeknesMorocco mathematics Department College of ScienceKing Khalid UniversityAbhaSaudi Arabia

This paper presents an extension of certain forms of the real Paley-Wiener theorems to the minkowski space-time algebra. Our emphasis is dedicated to determining the space-time valued functions whose space-time Fourier transforms(SFT) have compact support using the partial derivatives operator and the Dirac operator of higher order.

关键词： Paley-Wiener theorem minkowski algebra space-time algebra space-time Fourier transform

Structure Investigation of Xylenols and Their Redox Products by Thermal and Spectral methods of Analyses

在线全文

学校读者我要写书评

暂无评论

分析测试学报 1992年第4期 18-28页

作者： m.A.zayed Chemistry Department Cairo University Giza Faculty of Science A.R.egypt

The structures of 2, 6- and 3,4-xylenols together with their iodine redox products Ⅰ-Ⅲwere studied and critically investigated. Characterization of these matrials involves elemental, the-rmogravimetric, differential thermogravimetric and differential thermal analyses. IR and NmRspectrometry were used for the study of structural formulae of the obtained redox products. Theidentification and characterization of these materials confirm the proposed schemes representingredox reactions of xylenols with iodine. It also explained the schemes representing fragmentationof the investigated compounds by thermal analyses. Thin layer chromatography was also used forseparation and identification of redox products obtained in the reaction media.

关键词： Structure Investigation of Xylenols and Their Redox Products by Thermal and Spectral methods of Analyses

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

effect of Cobalt Doping on the microstructure and Tensile Properties of Lead Free Solder Joint Subjected to electromigration

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2016年第11期32卷 1129-1136页

作者： m.Nasir Bashir A.S.m.A.Haseeb Abu zayed mohammad Saliqur Rahman m.A.Fazal Department of mechanical engineering University of Malaya

Rapid Cu diffusion is one of the main causes of electromigration（em） failure in lead-free solder *** this study, an effort has been made to investigate the detrimental effects of em on microstructure and mechanical performance of solder joint by introducing Co nanoparticles（NP） doped flux at the interface between SAC305 solder and copper substrate. em tests were conducted on un-doped SAC305 and Co-doped SAC305 solder joints for different time intervals, with the maximum duration of 1128 h. A DC current was applied to the both types of solder joints to achieve a current density of 1 × 104A/cm2. em tests were performed in an oil bath maintained at a constant temperature of 80 °C. It is found that Codoped flux significantly reduced the formation of cracks and voids at the cathode interface. Co atoms entered into the lattice of Cu6Sn5 leading to the formation of（Cu, Co）6Sn5. This thermodynamically stabilized the interfacial intermetallic（ImC） layers both at the anode and cathode sides and suppressed the change in their thickness. The average anodic growth rate of（Cu, Co）6Sn5 interfacial ImC in the doped sample was about one order of magnitude lower compared with that of Cu6Sn5 in the un-doped ***-NP also improved the tensile strength considerably before and after em. The report suggests that the reliability of solder joint during em can be improved by using Co-NP doped flux.

关键词： electromigration damages Tensile strength Intermetallic compounds Nanoparticles Reliability

environmental chemical study on the marsh of Fatimid cemetery at Aswan City, egypt

在线全文

学校读者我要写书评

暂无评论

Journal of environmental Sciences 2002年第4期14卷 464-473页

作者： m.e.Soltan Chemistry Department Faculty of Science

environmental chemical study were carried out on the Fatimid cemetery marsh at Aswan City(24°1'N and 32°9'e), egypt. marsh contents(warter, soil, sediment, metal and nonmetal bearing salts, and emergent weed) were analysed to known the source of marsh water, speciation of the different elements between the marsh contents, and the toleration of emergent weed (Phargmites australies) for different metals and their bioaccumulation coefficients. Thus, metals(Ca, mg, Na, K, Ni, Fe, mn, Cu, Zn, Cd and Pb) and nonmetals(CO 2- 3, HCO - 3, Cl -, SO 2- 4, PO 3- 4, NO - 3, SiO 2, organic matter and pH value) were determined in the samples. According to the chemical analysis, and applying the base exchange equation(water type) and calculate the hydrochemical parameters for marsh water samples, we can indicate that the marsh water is ground water with Na SO 4 type and deep meteoric genesis. Topsoil of marsh dry land characterized by CaCl as dominant salt,while NaCl is a dominant salt in subsoil. The elevated pH values of marsh contents minimized the metal solubilities in different samples. Phragmites australies showed a strong ability to accumulate mn and Fe in the aerial part in opposite to Co, Ni and Cd.

关键词： marsh water soil sediment emergent weed egypt

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

Clinical correlates of common corneal neovascular diseases: a literature review

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(english edition) 2015年第1期8卷 182-193页

作者： Nizar Saleh Abdelfattah mohamed Amgad Amira A zayed Hamdy Salem Ahmed e elkhanany Heba Hussein Nawal Abd el-Baky Doheny Image Reading Center Doheny Eye InstituteUniversity of California Faculty of medicine Cairo University Department of Surgery Mayo Clinic Faculty of medicine University of Alexandria Department of medical Oncology Mayo Clinic Faculty of Oral and Dental medicine Cairo University Antibody Laboratory Protein Research DepartmentGenetic Engineering and Biotechnology Research InstituteCity for Scientific Research and Technology Applications

A large subset of corneal pathologies involves the formation of new vessels(neovascularization), leading to compromised visual acuity. This article aims to review the clinical causes and presentations of corneal neovascularization(CNV) by examining the mechanisms behind common CNV-related corneal pathologies, with a particular focus on herpes simplex stromal keratitis,contact lenses-induced keratitis and CNV secondary to keratoplasty. moreover, we reviewed CNV in the context of different types of corneal transplantation and keratoprosthesis, and summarized the most relevant treatment available so far.

关键词： cornea neovascularization herpes simplex keratitis keratoplasty contact lens keratoprosthesis

Influence of the Choice of NN Potential model on γd→τ~0d Observables near η-Threshold

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

Chinese Physics Letters 2016年第4期33卷 14-18页

作者： e.m.Darwish Physics Department Faculty of ScienceTaibah University Physics Department Faculty of ScienceSohag University

Influence of the choice of the NN potential model governing the deuteron wave function on the observables for coherent π0-photoproduction on the deuteron near η-threshom is investigated by using a three-body model for the intermediate ηN N system with separable two-body interactions. Results for unpolarized differential cross section and polarization observables are predicted. It is revealed that the choice of the NN potential model has a visible effect on the differential cross section and most of the polarization observables, especially in the photon energy range of 600-800 meV and extreme backward pion angles. We find that the deviation among results obtained by using different deuteron wave functions is quite large. The use of the CD-Bonn NN potential for deuteron wave function doubles the differential cross section in this kinematic region. Compared with the experimental data from CLAS collaboration for differential cross section, sizeable discrepancies are found.

关键词： of in Observables near Threshold NN that for on CLAS