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Transactions of Nonferrous Metals Society of China 2020年第7期30卷 1790-1802页

作者： Ren-jie FAN Shokouh ATTARILAR Mahmoud SHAMSBORHAN Mahmoud EBRAHIMI ceren gode Hatice VarolOZKAVAK Department of Mechanical Engineering Tongling Vocational and Technical CollegeTongling 244061China School of Metallurgy and Materials Engineering Iran University of Science and TechnologyTehranIran Department of Engineering Mahabad BranchIslamic Azad UniversityMahabadIran Department of Mechanical Engineering University of ZakhoZakhoKurdistan RegionIraq Department of Mechanical Engineering Faculty of EngineeringUniversity of MaraghehMaraghehIran School of Denizli Vocational Technology Program of MachinePamukkale UniversityDenizliTurkey Department of Mechanical and Metal Technology Technical Sciences Vocational SchoolIsparta University of Applied SciencesIspartaTurkey

The use of a constrained groove pressing(CGP) method to plastically deform AA6063 aluminum alloy led to the improved surface properties. It was found that hardness magnitude is dramatically improved and its uniformity is considerably decreased after the first pass, while subsequent passes result in better hardness behavior for the processed material. Also, the elongated grains formed in the first pass of the CGP are gradually converted to the equiaxed counterparts by adding pass numbers. Eventually, higher corrosion resistance of the sample by imposing the CGP process is related to the quick formation of passivation film and the change in the morphology of the second phase and precipitates which hinder their electrochemical reactions and decrease the potential localized attack sites.

关键词： mechanical properties corrosion resistance aluminum alloy constrained groove pressing technique grain refinement hardness distribution homogeneity

Severely deformed copper by equal channel angular pressing

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Progress in Natural Science:Materials International 2017年第2期27卷 244-250页

作者： M.Ebrahimi C.gode Department of Mechanical Engineering University of Maragheh School of Denizli Vocational Technology Program of MachinePamukkale University

Mechanical and microstructural analysis of equal channel angular pressed copper was experimentally investigated. The results showed that the hardness distribution uniformity was rapidly decreased after the first pass and gradually improved at the following passes. Also, the bottom region of the pressed material experienced lower Vickers hardness magnitude irrespective of pass number. Furthermore, the addition of 0.1%magnesium to the pure copper had a considerable effect on the distribution uniformity. In addition, the material fracture mode changed from ductile to brittle by the alteration of the dimples to cleavage planes ***, the formability index was dramatically reduced after the first pass and slowly improved at the succeeding passes. Eventually, ECAP process led to the increment of low angle grain boundaries and the decrease of high angle grain boundaries at the initial passes and vice versa at the subsequent ones.

关键词： Pure copper Equal channel angular pressing Mechanical properties Impact test Microstructural observation

Damage prediction of 7025 aluminum alloy during equal-channel angular pressing

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 990-998页

作者： M.Ebrahimi Sh.Attarilar C.gode F.Djavanroodi Department of Mechanical Engineering Iran University of Science and Technology Department of Materials Engineering Sahand University of Technology School of Denizli Vocational Technology Program of Machine Pamukkale University Department of Mechanical Engineering Imperial College

Equal-channel angular pressing （ECAP） is a prominent technique that imposes severe plastic deformation into materials to en- hance their mechanical properties. In this research, experimental and numerical approaches were utilized to investigate the mechanical prop- erties, strain behavior, and damage prediction of ECAPed 7025 aluminum alloy in various conditions, such as die channel angle, outer comer angle, and friction coefficient. Experimental results indicate that, after the first pass, the yield strength, ultimate tensile strength, and hardness magnitude are improved by approximately 95%, 28%, and 48.5%, respectively, compared with the annealed state, mainly due to grain re- finement during the deformation. Finite element analysis shows that the influence of die channel angle is more important than that of outer comer angle or friction coefficient on both the strain behavior and the damage prediction. Also, surface cracks are the main cause of damage during the ECAP process for every die channel angle except for 90°; however, the cracks initiated from the neighborhood of the central re- gions are the possible cause of damage in the ECAPed sample with the die channel angle of 90°.

关键词： aluminum alloys equal-channel angular pressing materials damage strain distribution mechanical properties

非负载和氧化铝负载的纳米CeO_2-ZrO_2和CeO_2-Te_2O_3固溶体催化CO氧化(英文)

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催化学报 2011年第5期32卷 800-806页

作者： M.Reddy BENJARAM Thrimurthulu gode Lakshmi KATTA Inorganic and Physical Chemistry Division Indian Institute of Chemical Technology

Ceria-zirconia(CZ)and ceria-terbia(CT)and alumina-supported ceria-zirconia(CZA)and ceria-terbia(CTA)solid solutions were synthesized by coprecipitation and deposition precipitation methods,*** characteristics and catalytic activity of the synthesized samples have been investigated using X-ray diffraction(XRD),high resolution transmission electron microscopy(HRTEM),X-ray photoelectron spectroscopy(XPS),Raman spectroscopy(RS),and Brunauer-Emmett-Teller(BET)surface area *** evaluate the catalytic properties,total oxygen storage capacity and CO oxidation activity measurements were carried *** XRD analyses revealed the formation of Ce0.75Zr0.25O2 phase for CZ and Ce0.5Zr0.5O2 and Ce0.6Zr0.4O2 phases for CZA samples,*** the formation of only Ce0.8Tb0.2O2-δphase was noted for both CT and CTA *** the supported and unsupported samples adopted a fluorite-type structure and exhibited cell parameters with respect to Vegard's *** HRTEM results indicated well-dispersed particles of the size around 5 *** RS measurements suggested the presence of oxygen vacancies due to defective structure *** XPS studies revealed the presence of cerium in both Ce 4+ and Ce 3+ oxidation states in different *** was found that CO oxidation for CTA occurs at very much lower temperature than CT,CZ,and CZA *** of these findings by correlating with the structural characterization studies are consolidated.

关键词： ceria zirconia terbia alumina-support deposition coprecipitation CO oxidation

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软件替换问题的经济学考虑

计算机工程与应用 1991年第5期27卷 138-148页

作者： D.K.gode 龙晓苑中国人民大学信息系

软件维护是软件预算中一个重要的组成部分。旧软件的维护费用在不断地增长,预计这种趋势还将会继续。对于信息系统的研究者和实践者来说,研究软件维护策略的问题日益重要。已经有不少文献对软件维护方面的技术问题做了介绍,然而对维护... 详细信息

软件维护是软件预算中一个重要的组成部分。旧软件的维护费用在不断地增长,预计这种趋势还将会继续。对于信息系统的研究者和实践者来说,研究软件维护策略的问题日益重要。已经有不少文献对软件维护方面的技术问题做了介绍,然而对维护经济学的研究还处在萌发阶段。尤其还未能从理论的角度,探求到维护与重写旧软件二者之间的权衡方法。本文提出了一个软件替换问题的经济模型。在已有的实践结果的基础上,我们可以这样假设:随着修改次数的增加及软件的扩充,软件的复杂度也随之迅速增加。不良代码将引起维护费用的剧增。因而,可能存在这样的一个时刻点(从经济学的意义上说),在该时刻重写系统是最佳的。它将减少系统的复杂度及由此而引起的维护费用。本文中提出的模型允许我们对各种重写策略进行经济学上的比较,由此来决定最佳的重写点。系统管理员可以从分析中得到一些有趣的推论。这些结论中包括系统大小的影响,基本技术的构造,以及高级技术对重写点及其活动周期费用的可适用性。为说明模型的可用性,给出了一数值例的说明。

关键词：软件维护软件替换经济学

Modelling Stand Dynamics after Selective Logging： Implications for REDD and Carbon Pools Estimations from Forest Degradation

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Journal of Life Sciences 2012年第7期6卷 801-816页

作者： Adrien Njepang Djomo gode Gravenhorst Anthony Kimaro Mamey Isaac 43 Trillium Crt Kingston ON K7K 6W9 Canada Faculty of Forest Sciences and Forest Ecology Centre for Tropical and Subtropical Agriculture and Forestry (CeTSAF) Georg-A ugust- Universitgtt Goettingen Buesgenweg 1 D-37077 GOttingen Germany World Agroforestry Centre (ICRAF) ICRAF Tanzania Programme P. O. Box 6226 Dar-es-Salaam Tanzania Department of Physical and Environmental Sciences University of Toronto Toronto Canada

Forest degradation and biomass damage resulting from logging is currently difficult to evaluate with satellite images, but contributes substantially to carbon emissions in the tropics. To address this situation, we modelled how changes in the minimum felling diameter affect stem density, basal area and the related carbon biomass at the end of the felling cycle （30 years） in a semi-deciduous natural forest in Cameroon. With new MFDs estimates, at 7% logging damage rate, we found that the stem density of initially harvestable trees reduces from 12.3 （50.4 MgC·ha^-1） to 6.7 （32.5 MgC·ha^-1） trees per ha and the number of initial residual trees increases from 80 （18.9MgC·ha^-1） to 85.7 （36.8 MgC·ha^-1） trees per ha. This corresponds to an avoided damage estimated at 17.9 MgC·ha^-1. We also found that increasing mortality and damage intensity also increases the damage on carbon biomass estimated to be 8.9 MgC·ha^-1 at 10% or to be 17.4 *** at 15% logging damage. Overall, our study shows that proper determination of MFD of logged species taking into consideration their capacity of reconstitution and the Reduced Impact Logging can avoid the loss of up to 35 MgC·ha^-1.

关键词： Carbon estimations felling cycle logging damage minimum felling diameter (MFD) moist tropical forest REDD,species reconstitution.

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气态硝酸在钙质山毛榉森林中沉降通量的研究

环境科学研究 1992年第3期5卷 42-48页

作者：齐立文 gode Gravenhorst Ansgar Karger Steve Lindberg 中国环境科学研究院北京100012 哥廷根大学橡树岭国家实验室

1987年5月至12月,在联邦德国哥廷根森林中,位于树冠不同高度上完成了气态硝酸浓度分布的测定。同时,还测定了森林中大气扩散参数。用模式计算出气态硝酸的沉降速度和沉降通量。结果表明,气态硝酸沉降通量平均约为26kg HNO_3—N/a·ha,... 详细信息

1987年5月至12月,在联邦德国哥廷根森林中,位于树冠不同高度上完成了气态硝酸浓度分布的测定。同时,还测定了森林中大气扩散参数。用模式计算出气态硝酸的沉降速度和沉降通量。结果表明,气态硝酸沉降通量平均约为26kg HNO_3—N/a·ha,气态硝酸浓度平均约为0.88μgHNO_3—N/m^3,夜间浓度下降,43m处(树冠上面)气态硝酸浓度高于33m(树冠中)。在第1至第10个实验里气溶胶中气态硝酸与硝酸盐的比值是0.3,而在第11～14个实验中约为1～3。

关键词：气态硝酸气溶胶沉降通量森林

Removal of Malathion from Aqueous Solutions and Waste Water Using Fly Ash

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Journal of Water Resource and Protection 2010年第4期2卷 322-330页

作者： Vinay K. Singh Ravi S. Singh Prem N. Tiwari Jai K. Singh Fethiye gode Yogesh C. Sharma 不详

Fly ash, obtained from a thermal power plant, Anpara, Sonebhadra, India has been used as an effective ad-sorbent for the removal of malathion from aqueous solutions. The time required to attain equilibrium was found to increase from 40 to 60 minutes as the initial malathion concentration increases from 1 to 10 mg/L. The optimum pH value for adsorption was 4.50. The removal of malathion increased by increasing the tem-perature indicating endothermic nature of removal process. The fly ash exhibited first order rate kinetics and followed both Langmuir and Freundlich isotherm models. Endothermic nature of adsorption process was further supported from increasing values of Langmuir and Freundlich constants with increase in temperature. The adsorbent can be used as an economical product for the removal of malathion from wastewater also. A comparison of the adsorption capacity of fly ash with other adsorbents shows that fly ash can be used for the removal of malathion from aqueous solutions.

关键词： Adsorption Wastewater Removal Fly Ash Malathion

Bacteriological Profile of Infections Encountered in a Pneumology Service in a Moderate-Income Country [Pneumology Department of CHU Cocody (Côte d’Ivoire)]

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Open Journal of Respiratory Diseases 2024年第1期14卷 1-11页

作者： Brou Jean Marcel Ahui Alitonde Eudoxie Djegbeton Alima Kone Marc-Olivier Koffi Kouame Clarisse Elogne Mobio Nancy Hermine Benjamin Kouraogo Erick Akouatia Constante Virginie Brou-gode Kigninlman Horo Boko Alexandre Kouassi Ngoran Koffi Pneumology Service Teaching Hospital of Cocody Abidjan C&#244te d’Ivoire Medical School of Abidjan University Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoire Pasteur Institute of Cô te d’Ivoire Abidjan C&#244te d’Ivoire

Introduction: Infections represent a real public health problem aggravating the morbidity and mortality of hospitalized patients. Methods: This was a retrospective study with descriptive purposes over a period of 05 years, in the Pneumology Department of the University Hospital of Cocody. Results: The average age in our population was 42 years. We observed a male predo- minance of 64.5%, with a sex ratio of 1.8. Medical history was dominated by HIV infection (23.5%), followed by tuberculosis (15.6%). Concerning lifestyle, smoking was found in 38% of cases. Symptoms progressed chronically in 80% of cases. An infectious syndrome was found in 75% of cases. Microbial culture was positive in 42% of cases. Pseudomonas aeruginosa and Klebsiella pneumoniae were encountered in 26.4% of cases each, followed by Echerichia coli in 10.4% of cases. Klebsiella pneumoniae in the first three years topped the list, but gradually. Pseudomonas aeruginosa maintained its leadership over the last three years. Pseudomonas aeruginosa isolates expressed a resistance rate of 9.8% to ceftazidime and 8.1% to imipenem;to aztreonam (36%), ticarcillin (33.3%) and levofloxacin. These strains were susceptible to fosfomycin (100%), mero- penem (96.6%) and amikacin (96%). For isolated strains of Entero- bacteria- ceae, resistance was observed about ticarcillin (83.3%) and amoxicillin clavula- nic acid (71.2%). Streptococcaceae showed resistance to tetracycline (69.2%) and erythromycin (50%). Over the years there has been an increase in re- sistance to amoxicillin-clavulanic acid ceftriaxone. The death rate was 14%. Conclusion: The bacterial profile of infections is dominated by germs respon- sible for nosocomial infection with significant mortality.

关键词： Bacterial Pleural Pneumonia Nosocomial Infection Sub-Saharan Africa Antibiotic Therapy

Ophthalmologic Repercussions of Orbital Fractures

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Open Journal of Ophthalmology 2023年第2期13卷 248-255页

作者： Philippe Emile France Koffi Bile Opokou Alexandre Demisères Ory Gosse François Diomande Kouassi Franck-Herman Koffi Ernest Martial Djemi Ange Mickael Goule Liliane Ella gode Raheemotu Llahi Opeyemi Babajeyu Zana Diabaté Yves Ouattara Ibrahim Abib Diomande Ophthalmology Department Bouaké University Hospital Bouake C&#244te d’Ivoire Maxillofacial Surgery and Stomatology Department Bouaké University Hospital Bouake C&#244te d’Ivoire

Orbital fractures refer to all continuity solutions involving the wall of the orbit. They are responsible for serious complications, particularly ophthalmological. Objective: To identify the epidemiological, anatomical and clinical aspects as well as the possible ocular complications of orbital fractures in the Gbêkê region. Methods: Prospective study from July 1, 2020, to October 31, 2020, i.e., a duration of 4 months. It took place in the ophthalmology department of the University Hospital of Bouaké. Patients with orbital fractures with ocular repercussions received during the study period were included. Results: Out of 27 cases of orbital floor fracture received, 20 had ocular complications, i.e., a prevalence of 74.07%. The average age was 32 years with extremes of 18 and 48 years. The male gender predominated with 80%, i.e. a sex ratio of 4. Subconjunctival hemorrhage was the most frequent reason for consultation (70%). The etiology was dominated by road traffic accidents (85%). The average consultation time was 24 hours. 80% of the patients had a distance visual acuity (DVA) between 3/10 and 10/10.) Diplopia was observed in 60% of patients. Blow out fracture (70%) was the most prominent orbital lesion. At the paraclinical level, 80% of the patients had performed a CT scan of the orbit. Evisceration was the predominant ophthalmologic surgical management (4 patients). At the bone level, reconstruction of the orbital floor with a polydioxanone plate (PDS) was performed in 50% of patients. Conclusion: The risk of ocular injury in orbital fractures is frequent because of the close relationship between the orbit and the eyeball.

关键词： Orbit Fracture Ophthalmologic Repercussions