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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, 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 comprehensive 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 optimization.

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Post-annealing effect on the structural and mechanical properties of multiphase zirconia films deposited by a plasma focus device

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Chinese Physics B 2013年第12期22卷 442-450页

作者： I.A.Khan R.S.Rawat R.Ahmad m.A.K.shahid Department of Physics Government College University National Institute of Education Nanyang Technological University Department of Physics GC University

Nanostructured multiphase zirconia films （mZFs） are deposited on Zr substrate by the irradiation of energetic oxygen ions emanated from a plasma focus device. The oxygen operating gas pressure of 1 mbar （1 bar=105 Pa） provides the most appropriate ion energy flux to deposit crystalline ZrO2 films. X-ray diffraction （XRD） patterns reveal the formation of polycrystalline ZrO2 films. The crystallite size （CS）, crystal growth, and dislocation densities are attributed to increasing focus shots, sample axial distances, and working gas pressures. Phase and orientation transformations from t-ZrO2 to m-ZrO2 and c-ZrO2 are associated with increasing focus shots and continuous annealing. For lower （200 ℃） annealing temperature （AT）, full width at half maximum （FWHm） of diffraction peak, CS, and dislocation density （δ） for （020） plane are found to be 0.494, 16.6 nm, and 3.63×10-3 nm-2 while for higher （400 ℃） AT, these parameters for （111） plane are found to be 0.388, 20.87 nm, and 2.29×10-3 nm-2, respectively. Scanning electron microscope （SEm） results demonstrate the formation of rounded grains with uniform distribution. The estimated values of atomic ratio （O/Zr） in ZrO2 films deposited for different axial distances （6 cm, 9 cm, and 12 cm） are found to be 2.1, 2.2, and 2.3, respectively. Fourier transform infrared （FTIR） analysis reveals that the bands appearing at 441 cm-1 and 480 cm-1 belong to m-ZrO2 and t-ZrO2 phases, respectively. maximum microhardness （8.65±0.45 GPa） of ZrO2 film is ～ 6.7 times higher than the microhardness of virgin Zr.

关键词： zrconia phase transformation XRD SEm Fourier transform infrared analysis

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multi-objective vendor managed inventory system with interval type-2 fuzzy demand and order quantities

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International Journal of Intelligent Computing and Cybernetics 2021年第3期14卷 439-466页

作者： Zubair Ashraf mohammad shahid South Asian University New DelhiIndiaand Aligarh muslim University AligarhIndia

Purpose-The proposed IT2FmOVmI model intends to concurrently minimize total cost and warehouse space for the single vendor-retailer,multi-item and a consolidated vendor *** demand and order quantities with the deterministic and type-1 fuzzy numbers,we have also formulated the classic/crisp mOVmI model and type-1 fuzzy mOVmI(T1FmOVmI)*** suggested solution technique can solve both crisp mOVmIand *** finding the optimal ordered quantities and backorder levels,the Paretofronts are constructed to form the solution sets for the three ***/methodology/approach-A multi-objective vendor managed inventory(mOVmI)is the most recognized marketing and delivery technique for the service provider and the retail in the supply chain in Industry *** to the evolving market conditions,the characteristics of the individual product,the delivery period and the manufacturing costs,the demand rate and order quantity of the mOVmI device are highly *** such a scenario,a mOVmI system with a deterministic demand rate and order quantity cannot be designed to estimate the highly unforeseen cost of the *** paper introduces a novel interval type-2 fuzzy multi-objective vendor managed inventory(IT2FmOVmI)system,which uses interval type-2 fuzzy numbers(IT2FNs)to represent demand rate and order *** the model is an NP-hard,the well-known meta-heuristic algorithm named NSGA-II(Non-dominated sorted genetic algorithm-II)with EKm(Enhanced Karnink-mendel)algorithm based solution method has been ***-The experimental simulations for the five test problems that demonstrated distinct conditions are considered from the real-datasets of SAPCO *** study concludes that T1FmOVmI and crisp mOVmI schemes are outclassed by IT2FmOVmI model,offering more accurate Pareto-Fronts and efficiency measurement ***/value-Using fuzzy sets theory,a significant amount of work has been already done in past

关键词： multi-objective vendor managed inventory Interval type-2 fuzzy demand Interval type-2 fuzzy ordered quantity Industry 4.0 NSGA-II

Determination of consolidation behaviour of clay slurries

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International Journal of mining Science and Technology 2016年第2期26卷 277-283页

作者： Khan Faseel S. Azam shahid Environmental Systems Engineering University of Regina

The main objective of this study was to determine the consolidation behaviour of clay slurries.A finegrained clay with high consistency limits(W_L = 180%,w_P= 120%) was investigated using conventional oedometer and bench-top centrifuge *** indicated that the slurry had an apparent preconsolidation(due to initial conditions,electrochemical interactions,tortuous drainage,and thixotropic strength) from e = 5.7 to e = 5.5 followed by virgin ***,the low hydraulic conductivity(10^(-10)-10^(-12) m/s) was due to low porosity(small pore throats) and high tortuosity(long flow paths).Unlike consolidation of soils,the c_v and m_v decreased with increasing σ' but increased with increasing e and *** data from the two tests correlated well in the range of σ' = 10-65 kPa,e = 5.5-3.86,k= 1.7 × 10^(-10)-5×10^(-11) m/s,F_c = 1-40 *** equations were developed to correlate the consolidation parameters(e,σ',k) with F_*** deviation of k beyond 40 mN(e = 4.65) was due to deviation from the initial straight line portion of the settlement curve in the centrifuge test.

关键词： Clay slurry Consolidation Conventional oedometer test Bench-top centrifuge

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iRNA-PseTNC:identification of RNA 5-methylcytosine sites using hybrid vector space of pseudo nucleotide composition

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Frontiers of Computer Science 2020年第2期14卷 451-460页

作者： shahid AKBAR maqsood HAYAT muhammad IQBAL muhammad TAHIR Department of Computer Science Abdul Wali Khan University MardanKP 23200Pakistan

RNA 5-methylcytosine(m^5C)sites perform a major role in numerous biological processes and commonly reported in both DNA and RNA *** enzymatic mechanism and biological functions of m^5C sites in DNA remain the focusing area of researchers for last few ***,the investigators also targeted m^5C sites in RNA due to its cellular functions,positioning and formation ***,several rudimentary roles of the m^5C in RNA have been explored,but a lot of improvements are still under ***,the identification of RNA methylcytosine sites was carried out via experimental methods,which were very hard,erroneous and time consuming owing to partial availability of recognized *** at the significance of m^5C role in RNA,scientists have diverted their attention from structure to sequence-based *** this regards,an intelligent computational model is proposed in order to identify m^5C sites in RNA with high *** RNA sequences formulation methods namely:pseudo dinucleotide composition,pseudo trinucleotide composition and pseudo tetra nucleotide composition are applied to extract variant and high profound numerical *** a sequel,the vector spaces are fused to build a hybrid space in order to compensate the weakness of each *** learning hypotheses are examined to select the best operational engine,which can truly identify the pattern of the target *** strength and generalization of the proposed model are measured using two different cross validation *** reported outcomes reveal that the proposed model achieved 3%better accuracy than that of the highest present approach in the literature so far.

关键词： methylcytosine sites PseTNC PseTetraNC hybrid features SVm cross validation test

Induced modifications in the properties of Sr doped BiFeO3 multiferroics

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Progress in Natural Science:materials International 2013年第5期23卷 487-492页

作者： Tanvir Hussain Saadat A.Siddiqi shahid Atiq m.S.Awan Centre of Excellence in Solid State Physics Quaid-e-Azam CampusUniversity of the Punjab Interdisciplinary Research Centre in Biomedical materials (IRCBm) COMSATS Institute of Information Technology Department of Physics COMSATS Institute of Information Technology

multiferroics exhibit unique combination of ferroic properties,*** instance,in BiFeO3,magnetic and electric properties *** this work,BiFeO3 and Sr-doped BiFeO3 samples with general formula,Bi1-x Srx FeO3(x=0.00,0.05,0.10,0.20,and 0.30) were synthesized by sol-gel auto-combustion technique,in order to investigate these ferroic *** samples were confrmed to have perovskite type rhombohedral structure,characteristic of BiFeO3.A dilute phase of Bi2Fe4O9was also found in all the Sr-doped *** micrographs of the palletized samples revealed that minutely doped Sr might not have any effect on the morphology of the *** dependent dielectric measurements were carried out at room temperature for all the samples from 100 Hz to 1 *** dielectric constant of un-doped sample at low frequency was 52 which decreased with increasing Sr *** enhancement of magnetic properties was observed with increasing the Sr *** BiFeO3 material was observed to have the least value of remanent *** the Sr2+ tions were doped in BiFeO3,its magnetization and remanence were increased to 0.867 emu/g and 0.175 emu/g,respectively,at x=0.30.

关键词： Bismuth ferrite Ferroelectricity Ferromagnetism Nanomaterials magnetically ordered materials

Comparative study on occurrence of class A and class Cβ-lactamase genes and their co-occurrence in Indian Enterobacteriaceae during years 2009 and 2010

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Asian Pacific Journal of Tropical medicine 2011年第10期4卷 764-768页

作者： Anuradha Singh mohd shahid Farrukh Sobia Umesh Haris m Khan Section of Antimicrobial Agents & Drug Resistance Research and molecular Biology Department of MicrobiologyJawaharlal Nehru Medical College & HospitalAligarh Muslim UniversityAligarh-202002Uttar PradeshIndia Department of medical microbiology Immunologyand Infectious DiseasesCollege of Medicine & Medical SciencesArabian Gulf UniversityKingdom of Bahrain Department of microbiology Government Medical CollegeHaldwaniUttrakhandIndia

Objective:To determine the occurrence of class A and class Cβ-Iactamase genes and their cooccurrence in Indian ***:52 third generation cephalosporin resistant isolates were phenotypically detected by combination disk method and screened by PCR to identify class A and class C typeβ-lactamase ***:Of the 52 isolates,94.2%（49） were found harboring any of the bla?,blaCTX-m,blaSHV and blaTEm were present in 82.6%（43/52）, 59.6%（31/52）,and 42.3%（22/52） isolates,*** the 49 ESBL positive isolates 57.1% （28/49） showed co-occurrence of blaampCwith bla?.On the contrary,the collection from 2009 showed their co-occurrence in 81.4%***:The comparative study shows a downward trend for co-existence of bla? with blaampC from 2009 to *** large scale studies are needed to address the co-occurrence of class A and class Cβ-lactamases in India and the resistance trend occurring over a period of time.

关键词： Class A ESBL Class C ESBL CTX-m AmpC Enterobacteriaceae India

Adsorption of phosphate on magnetite-enriched particles (mEP) separated from the mill scale

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Frontiers of Environmental Science & Engineering 2019年第5期13卷 81-92页

作者： muhammad Kashif shahid Yunjung Kim Young-Gyun Choi Department of Environmental Engineering Chungnam National UniversityDaejeon 34134Republic of Korea mechanical Process Research Group Engineering CenterPOSCO E&CIncheon 220099Republic of Korea

Phosphate is a major pollutant in water, causing serious environmental and health consequences. In present study, the phosphate adsorption on novel magnetite-enriched particles (mEP) was comprehensively investigated. A new method and device were introduced for the separation of mEP from the mill scale at low magnetic intensity. Particles were characterized with different techniques such as XRD, XRF, SEm and EDS. The XRD and XRF analysis of mEP identified the dominant existence of crystalline magnetite. Furthermore, the morphological analysis of mEP confirmed the agglomerate porous morphology of magnetite. Oxygen and iron, the main constituents of magnetite were acknowledged during the elemental analysis using EDS. The phosphate adsorption on mEP is well explained using various isotherm and kinetic models, exhibiting the monolayer adsorption of phosphate on the surface of mEP. The maximum adsorption capacity was determined 6.41 mg/g. Based on particle size (45–75 and 75–150 μm) and empty bed contact time (1 and 2 h), four columns were operated for 54 days. mEP were appeared successful to remove all phosphate concentration from the column influent having 2 mg/L concentration. The operated column reactors were successfully regenerated with alkaline solution. The results indicated potential for practical application of the mEP for phosphate removal.

关键词： Adsorption magnetite mill-scale Phosphate Wastewater treatment

Chemical Hide and Seek: Nematode’s Journey to Its Plant Host

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molecular Plant 2020年第4期13卷 541-543页

作者： Natalie Hamada Henok Zemene Yimer Valerie m.Williamson shahid Siddique Department of Entomology&Nematology University of California DavisDavisCA 95616USA Department of Plant Pathology University of California DavisDavisCA 95616USA

Plant-parasitic nematodes are among the most destructive plant pathogens,causing estimated damage of more than US$100 billion per *** expert-based assessment of crop health listed nematodes as among the most damaging pests and pathogens in potato,soybean,and wheat crops(Savary et al.,2019).most damage is caused by a small group of root-infecting sedentary endoparasitic nematodes including cyst nematodes and rootknot nematodes(RKNs).Second-stage juveniles(J2s)of plantparasitic nematodes hatch from eggs into the soil and localize to the roots of host *** success of these non-feeding J2s depends on their ability to locate and infect a suitable *** attraction of plant-parasitic nematodes to the host root has been a subject of study for the past 80 years following the pioneering research that demonstrated the attraction of RKN specifically toward root tips(Lindford,1939).Both volatile and soluble components in the rhizosphere have been shown to influence nematode movement.

关键词： soybean crops soil

Evaluation of potential RNA-interference-target genes to control cotton mealybug, Phenacoccus solenopsis （Hemiptera： Pseudococcuidae）

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Insect Science 2018年第5期25卷 778-786页

作者： Arif m. Khan muhammad Ashfaq Azhar A. Khan muhammad T. Naseem shahid mansoor National Institute for Biotechnology and Genetic Engineering Faisalabad Pakistan Department of Biotechnology University of Sargodha Sargodha Pakistan Biodiversity Institute of Ontario University of Guelph Guelph Ontario Canada College of Agriculture Bahauddin Zakariya University Bahadur Campus Layyah Pakistan

RNA interference （RNAi） of vital insect genes is a potential tool for targeted pest control. However, selection of the right target genes is a challenge because the RNAi efficacy is known to vary among insect species. Cotton mealybug, Phenacoccus solenopsis, is a phloem-feeding economically important crop pest. We evaluated the RNAi of 2 vital genes, Bursicon （PsBur） and V-ATPase （Ps V-ATPase） as potential targets in P. solenopsis for its control. PCR fragments of PsBur and PsV-ATPase were amplified using cDNA synthesized from the total RNA. The PCR amplicons were cloned into Potato virus X （PVX） to develop recombinant PVX for the inoculation ofNicotiana tabacum plants for bioassays with healthy P. solenopsis. Reverse-transcription-polymerase chain reaction （RT- PCR） was used to validate the expression oftransgenes in the recombinant-PVX-inoculated plants （treated）, and suppression of the target genes in the mealybugs exposed to them. The RT-PCR confirmed the expression of transgenes in the treated plants. mealybug individuals on treated plants either died or showed physical deformities. Further, the population of mealybug was significantly reduced by feeding on N. tabacum expressing RNAi triggers against PsBur and Ps V-A TPase. The results conclude that RNAi is activated in P. solenopsis by feeding on N. tabacum expressing RNAi triggering elements of PsBur and Ps V-ATPase genes through recombinant PVX vector. Further, V-ATPase and Bursicon genes are potential targets for RNAi-mediated control ofP. solenopsis.

关键词： insect control phloem feeders Potato virus X RT-PCR transgenic crops