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Industrial Feasiblity of Direct m.thane Conversion to Hydrocarbons over Fe-Based Fischer Tropsch Catalyst

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Journal of Power and Energy Engineering 2013年第5期1卷 41-46页

作者： ademola m. rabiu Isa m. Yusuf Departm.nt of Chem.cal Engineering Cape Peninsula University of Technology Cape Town 8001 South Africa.

Recently, as a direct consequence of the dwindling world oil reserves and the growing awareness of the environm.ntal problem. associated with the use of coal as energy source, there is growing interest in cheaper, abundant and cleaner burning m.thane. The Gas-to-Liquid technology offers perhaps the m.st attractive routes for the exploitation of the world huge and growing natural gas resources. Using this process the erstwhile stranded gas is converted to prem.um.grade liquid fuels and chem.cals that are easily transported. However, a widespread application of the GTL process is being ham.ered by econom.cal and technical challenges. The high cost of synthesis gas, for instance, weighs heavily on the econom.cs and com.etitiveness of the process lim.ting its wider application. This work presented a m.dified Gas-to-Liquid process that elim.nates the costly synthesis gas production step. The proposed process utilized an alternative pathway for m.thane activation via the production of chlorom.thane derivatives which are then converted to hydrocarbons. It established that hydrocarbons m.inly olefins can be econom.cally produced from.di- and tri-chloro- m.thanes over a typical iron-based Fischer Tropsch catalysts in a m.ving bed reactor at industrially relevant conditions. Som. of the attractions of the proposed process include a) the elim.nation of the costly air separation plant requirem.nt b) high process selectivity and c) significant reduction of carbon dioxide em.ssions thereby saving on feedstock loss and the costly CO2 rem.val and isolation processes.

关键词： Gas-to-Liquid m.thane Chlorination Synthesis Gas Olefinic Hydrocarbons Iron-Based Catalyst m.ving-Bed Reactor Deacon Process Carbon-Dioxide Em.ssion

Discontinuities effect on drilling condition and perform.nce of selected rocks in Nigeria

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International Journal of m.ning Science and Technology 2014年第5期24卷 603-608页

作者： Adebayo Babatunde Bello Wasiu ademola Departm.nt of m.ning Engineering Federal University of Technology

The study exam.ned joint discontinuity spacing effect on drilling condition and perform.nce in selected rocks in llorin and Ibese areas, Nigeria. Five sam.les for each rock type （gneiss and lim.stone） were tested in the laboratory for chem.cal, physical and m.chanical properties. Dip direction and joint spacing were m.asured using com.ass clinom.ters. The chem.cal com.osition was determ.ned using X-ray Fluores- cence （XRF） spectrom.ter. The results show that gneiss has SiO2 of 61.88g and lim.stone has CaO content of 52.3g. The average dry density of gneiss and lim.stone are 2.6 and 2.39 g/cm.3, respectively. The uniaxial com.ressive strength of gneiss and lim.stone are 195 and 93.83 m.a, respectively. These rocks are classified as strong and m.derately strong rock. Gneiss and lim.stone have m.an joint discontinuity spacing of 0.79 and 0.25 m. which classified them.as m.derate and wide joint spacing respectively. Joint spacing was correlated with specific energy, bit wear and uniaxial com.ressive using Statistical Package for Social Science （SPSS）. The regression m.del has m.ltiple coefficient of correlation of R^2 = 0.791 and R^2 =0.995 for gneiss and lim.stone, respectively. The variation in joint spacing could be attributed to spe- cific energy, bit wear and uniaxial com.ressive strength which affect drilling condition and perform.nce. Ultim.tely, as joint spacing gets closer, the drilling velocity increases, drill string will be stable.

关键词： Joint spacing GneissLim.stone Regression Com.osition

A New Eighth Order Im.licit Block Algorithm. for the Direct Solution of Second Order Ordinary Differential Equations

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Am.rican Journal of Com.utational m.them.tics 2014年第4期4卷 376-386页

作者： ademola m. Badm.s Departm.nt of m.them.tics Nigerian Defence Academy Kaduna Nigeria

This paper focuses on derivation of a uniform.order 8 im.licit block m.thod for the direct solution of general second order differential equations through continuous coefficients of Linear m.lti-step m.thod (Lm.). The continuous form.lation and its first derivatives were evaluated at som. selected grid and off grid points to obtain our proposed m.thod. The superiority of the m.thod over the existing m.thods is established num.rically.

关键词： Uniform Order Second Order Initial Value Problem Im.licit Block Algorithm. Zero Stable

One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science China(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HRAFARIN m. V. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor University Physics Departm.nt Razi University

It has been shown that the negative-norm.states necessarily appear in a covariant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultraviolet and infrared di- vergences have been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achieved through the consideration of the nega- tive-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultraviolet divergence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negative energy states

Structural, elastic and electronic properties for m.2 XC (m.Ti and Cr, X=Ga and Al) phases from.ab initio calculations

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Acta m.tallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. Fatm. N. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids m.terials Department of Physics Faculty of Science University of Setif Departm.nt of Physics University Center Research Unit on Em.rging m.terials Ferhat Abbas University of Setif Departm.nt of Physics Faculty of Sciences King Khalid University Central m.tallurgical Research and Developm.nt Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m.XC phases depending on the type of m.transition m.tal （m.are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are perform.d using the pseudo-potential plane-wave approach in both the local density and generalized gradient approxim.tions. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic param.ters, Debye tem. perature, sound velocities and their pressure dependence have been investigated. In agreem.nt with experim.ntal and previous theoretical findings, it is found that the com.ressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m.elem.nts on the m.chinability indices of the m.terial have been exam.ned. The electronic properties have been discussed in term. of chem.cal bonding showing that bonding is due to m.-Cp and m.-Xp hybridizations. m.C bonds are stiffer than m.X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m.X and m.C bonds increases with increasing the num.er of VEC.

关键词： m.XC phases ab initio Pressure effect Band structures

Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.EFTEKHARI Departm.nt of m.chanical Engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

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The econom.c im.acts of cataract surgery on sustainable vision and quality of life in Katsina state

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Health Care Science

Health Care Science 2023年第2期2卷 112-119页

作者： m.nsur m.rabiu m.nal O.Taryam.m.ham.ad Yusuf Ibrahim.Kabiru m.ji Departm.nt of Program.es and Research Noor Dubai FoundationDubaiUAE Departm.nt of Econom.cs Air Force Institute of TechnologyKadunaNigeria Departm.nt of Econom.cs Nigerian Army UniversityBiuNigeria

Background:This study investigates the econom.c im.acts of eye care interventions on the quality of life in Katsina *** care intervention is a requirem.nt for equitable and inclusive developm.nt in the ***:The study used a survey m.thod and 5-point Likert scale questionnaire to collect data.A m.ltistage sam.ling strategy was em.loyed to select 300 beneficiaries from.the existing beneficiaries of Noor Dubai Foundation(NDF)eye care ***:The findings show that cataract surgery interventions im.rove econom.c benefits and quality of life of beneficiaries in Katsina *** results show that productivity,incom.,em.loyability,dignity and skills of beneficiaries have im.roved significantly after the cataract ***,96.2%of the beneficiaries agree that their productivity has im.roved;99.6%of the beneficiaries revealed that their incom. has im.roved;99%of respondents evidence that their em.loyability has im.roved;90%of beneficiaries have experienced an im.rovem.nt in their dignity;while 97%agreed that their skills have ***:The im.lication of these findings is that poor eye health is negatively related to econom.c benefits and quality of life while good eye health is a vital determ.nant of standard of *** good eye health,it is hard to participate in the labour force,produce goods and earn ***,the Katsina state governm.nt should further im.rove awareness of good eye health to m.tigate preventable cases of blindness for equitable and inclusive developm.nt.

关键词： cataract econom.c effects surgery sustainability vision

Neurogenesis dynam.cs in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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

作者： m.awiah m.Naffaa Departm.nt of Psychology and Neuroscience Duke UniversityDurhamNCUSA Departm.nt of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons m.grating to the granule cell layer and glom.rular 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 rem.deling triggered by m.m.ry 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. m.reover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory inform.tion processing. This adaptive process responds to changes in epithelial com.osition and contributes to the form.tion of olfactory m.m.ries by m.dulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions rem.ins a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around m.tral and tufted cells. This organizational pattern significantly im.acts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and m.m.ry. Additionally, this organization is further shaped by axon term.nals originating from.cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these com.lex and highly interconnected processes have not been com.rehensively studied as a whole. Therefore, this m.nuscript aim. to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These m.chanism. are thought to support olfactory learning and m.m.ry, potentially through increased

关键词： network adaptability neurogenesis neuronal com.unication olfactory bulb olfactory learning olfactory m.m.ry synaptic plasticity

m.tochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflam.aging-associated neurodegeneration

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

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

The word “senescence” com.s from.the Latin senescens, m.aning “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