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Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.MUhAMMAD M.SARFRAZ Department of humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(MhD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in MAThEMATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词： convective boundary condition Darcy-Forchheimer medium hybrid nanofluid Joule heating magnetohydrodynamic (MhD) numerical solution squeezing flow regression analysis O361 O175.2

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOSSEINI O.BALILAShAkI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： point source cylindrical cavity porous medium wave-field transformation stress concentration O353.4

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新型四象限变流器控制方法

机车电传动 1991年第2期 47-50,13页

作者： k.hückelheim 徐瑛

三相交流传动系统成功地用于接触网式机车上的最重要的先决条件是采用四象限变流器(见图1),它能保证机车牵引和制动时电网电流的谐波含量低。一方面由于控制特性、适应性(双流制机车)和诊断功能的新要求,另一方面是由于微处理机的市场趋... 详细信息

三相交流传动系统成功地用于接触网式机车上的最重要的先决条件是采用四象限变流器(见图1),它能保证机车牵引和制动时电网电流的谐波含量低。一方面由于控制特性、适应性(双流制机车)和诊断功能的新要求,另一方面是由于微处理机的市场趋势,使人们有必要放弃以前采用的模拟硬件方法来进行四象限变流器控制,而开发一种以微处理机为基础的新方法。

关键词：四象限变流器控制变流器机车

700℃ ISOThERMAL SECTION OF ThE Pd-Ru-Gd PARTIAL PhASE DIAGRAM

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Acta Metallurgica Sinica(English Letters) 1996年第5期9卷 329-332页

作者： k.h Zhang and L.L. Chen (Institute of Precious Metals, kunming 650221, China)

The 700℃ isothermal section of the Pd-Ru-Gd partial ternary phase diagram containing more palladium than ruthenium was determined by X-rag diffraction analysis and optical microscopy. The section consists of seven single-phase regions,eleven two-phase regions and five three-phase regions. A new ternary compound Pd2RuGd2,which exhibits a tetragonal structure with a=0.7492 nm and c=0.7445 nm, has been found.

关键词： palladium ruthenium gadolinium phase diagram Pd-Ru-Gd ternary sgstem

NECAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael k.E.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. however, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium EF hand mitochondria nervous system signal transduction

What is schizophrenia? 25 years of research into schizophrenia-the Age Beginning Course Study

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World Journal of Psychiatry 2015年第2期5卷 167-169页

作者： heinz h?fner Schizophrenia Research Group Central Institute of Mental Health Mannheim Faculty of Medicine/University of Heidelberg

We studied a population-based sample of 232 firstonset cases of schizophrenia aged 12 to 59 years at first admission retrospectively back to illness onset and prospectively up to 11.2 years later. We compared them with psychiatrically healthy age- and sexmatched population controls and equally matched firstadmission patients diagnosed with major depression. At schizophrenia onset women are several years older than men. The social factors tested did not explain the finding. Women's higher level of social development at onset is associated with a better medium-term functional and social outcome. Prodromal schizophrenia and depression are equal in length and diagnostically distinguishable only after the onset of positive symptoms. The sex difference in age at onset, invariable across cultures and ethnicities, is explained by a protective effect of oestrogen, which down-regulates D2 receptors. A higher genetic load antagonizes this effect. Long-term symptom-related illness course exhibits a plateau after three years, the positive symptom dimension after two years, the depressive and the negative dimensions do so after three to five years. The most prevalent symptom is depressive mood. Male first episodes are more frequent and more severe in the first half of life, female ones in the second half. Aetiological conclusions will be drawn.

关键词： Schizophrenia and depression Symptom dimensions Types of illness course Sex Age

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris k.Salgado Jose M.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis h.Pagan Rivera Jorge D.Miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Comparable Study of Xylanase Production from Aspergillus niger via Solid State Culture

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Journal of Chemistry and Chemical Engineering 2012年第12期6卷 1106-1113页

作者： Norazhna I Pushpahvalli B ku halim k.h Norakma M.N Faculty of Engineering Universiti Selangor Bestari Jaya 45600 Malaysia Faculty of Science and Biotechnology Universiti Selangor Bestari daya 45600 Malaysia Faculty of Chemical Engineering Universiti Teknologi Mara Selangor 40450 Malaysia

With the high availability of agricultural wastes in Malaysia, green energy is practical to be conducted. Thus, a research on the modification of the physical conditions of the solid state culture system, specifically different initial moisture content, fermentation temperature, inoculums size and different percentage of carbon and nitrogen sources were conducted to compare the usage of two different lignocellulosic materials which were oil palm frond and banana petiole respectively. After using a conventional method （one factor at a time）, the optimum fermentation conditions would be a combination of 70% initial moisture content （v/w）, at 28 ~C fermentation temperature with supplementation of 1% sucrose （w/w） and 1% peptone using 1 mL of inoculum in order to achieve highest xylanase production which was 1,711.87 U/mL and 1,579.60 U/mL for oil palm frond and banana petiole respectively. It was suggested that oil palm frond showed higher xylanase production compared to banana petiole.

关键词： Xylanase solid state culture Aspergillus niger oil palm frond banana petiole.

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集装箱班轮公司航次运力销售过程优化模型

交通运输工程学报 2015年第2期15卷 79-89页

作者：殷明时恒金甲焕上海海事大学交通运输学院上海201306 同济大学交通运输工程学院上海201804 釜山大学工学院

基于种群演变和共生理论，采用 Cobb-Douglas 生产函数描述航运市场整体需求，从顾客的购买行为出发，以收益最大作为集装箱班轮公司的经营目标，以基于时间序列的运力与运价作为决策变量，构建了集装箱班轮公司航次运力销售过程优化模... 详细信息

基于种群演变和共生理论，采用 Cobb-Douglas 生产函数描述航运市场整体需求，从顾客的购买行为出发，以收益最大作为集装箱班轮公司的经营目标，以基于时间序列的运力与运价作为决策变量，构建了集装箱班轮公司航次运力销售过程优化模型。运用 Taylor 公式与最小二乘法等代数变换手段将非线性规划问题转化为线性规划问题，对关键参数进行了标定与敏感性分析，并利用MATLAB 软件进行仿真验证。仿真结果表明：当单个集装箱班轮公司的运力为104 TEU 时，采用常规的销售策略，集装箱班轮公司可售出的运力为7534～9966 TEU，获得收益为1233158～12915936 USD，采用提出的优化模型，可售出的运力为9915 TEU，获得收益为15111975 USD，收益至少提高17％；当2个集装箱班轮公司的运力均为104 TEU 时，采用提出的优化模型，2个集装箱班轮公司可售出的运力分别为9920、9947 TEU，获得收益分别为14241771、9737528 USD，达到纳什均衡；当3个集装箱班轮公司的运力均为104 TEU 时，采用提出的优化模型，3个集装箱班轮公司可售出的运力分别为8289、5526、6034 TEU，获得收益分别为6755755、6119906、4377758 USD，达到纳什均衡。可见提出的模型可描述多个集装箱班轮公司运力销售情况，且表现出显著的优化效果。

关键词：集装箱运输收益管理种群演变共生理论舱位存量定价