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Applied Mathematics and Mechanics(English Edition) 2021年第5期42卷 721-746页

作者： A.T.TrAN h.LE qUANG q.C.hE D.h.NGUYEN research and Application Center for Technology in Civil Engineering University of Transport and CommunicationsHanoi 10000Vietnam Laboratoire Modelisation et Simulation Multi-Echelle Unite Mixte de Recherche 8208Centre National de la Recherche ScientifiqueUniversite Gustave EiffelMarne-la-Vallee F-77454France School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China

The present work is concerned with a two-dimensional(2D)Stokes flow through a channel bounded by two parallel solid *** distance between the walls may be arbitrary,and the surface of one of the walls can be arbitrarily *** main objective of this work consists in homogenizing the heterogeneous interface between the rough wall and fluid so as to obtain an equivalent smooth slippery fluid/solid interface characterized by an effective slip *** solve the corresponding problem,two efficient numerical approaches are elaborated on the basis of the method of fundamental solution(MFS)and the boundary element methods(BEMs).They are applied to different cases where the fluid/solid interface is periodically or randomly *** results obtained by the proposed two methods are compared with those given by the finite element method and some relevant ones reported in the *** comparison shows that the two proposed methods are particularly efficient and accurate.

关键词： effective slip length method of fundamental solution(MFS) boundary element method(BEM) Stokeslet micro-channel fluid/solid interface

Observability Analysis of Integrated Electricity and heating Systems with Thermal quasi-dynamics in Pipelines

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1145-1158页

作者： Zhigang Li Wenjian Zheng Junbo Zhao J.h.Zheng q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China Fuzhou Changle District Power Supply Company of State Grid Fujian Electric Power Co. Ltd.Fuzhou 350000China Department of Electrical and Computer Engineering University of ConnecticutStorrsCT 06269USA CSEE IEEE

Observability analysis(OA)is vital to obtaining the available input measurements of state estimation(SE)in an integrated electricity and heating system(IEhS).Considering the thermal quasi-dynamics in pipelines,the measurement equations in heating systems are dependent on the estimated results,leading to an interdependency between OA and *** OA methods require measurement equations be known exactly before SE is performed,and they are not applicable to *** bridge this gap,a scenario-based OA scheme for IEhSs is devised that yields reliable analysis results for a predefined set of time-delay scenarios to cope with this *** its core procedure,the observable state identification and observability restoration are formulated in terms of integer linear *** tests are conducted to demonstrate the validity and superiority of the proposed formulation.

关键词： Integrated electricity and heating system measurement observability analysis state estimation thermal quasi-dynamics

Leaching of rare Earth elements from an Illinois basin coal source

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Journal of rare Earths 2019年第3期37卷 312-321页

作者： X.Yang J.Werner r.q.honaker Department of Mining Engineering University of Kentucky

The existence of rare earth elements(rEEs) in coal sources at elevated concentrations has been the focus of several studies over the past decade. however, limited research has been conducted on methods to recover and refine the rEEs. This paper reports the results of a detailed study into the potential of selectively recovering rEEs in an Illinois basin coal source by leaching. Leaching characteristics are obtained for several segments obtained from a core sample as well as three different reject materials collected at a coal processing plant. Using a 1.2 mol/L sulfuric acid solution at 75 ℃,over 60% rEE recovery is achieved from the direct floor and an inner parting material as well as the coal-rich core segments that are pretreated by low-temperature plasma oxidation to obtain access to the microdispersed mineral matter. In the leachable parting material, fluorapatite is detected by XrD analysis,which is one of the more soluble phosphate minerals with a documented association with rEEs. For the three plant reject samples, the leaching recovery values obtained for the heavy rEEs are higher than those obtained for the light rEEs under the standard leaching conditions and when 0.1 mol/L(Nh_4)_2SO_4 was used to extract rEEs by an ion exchange mechanism. Thermal activation by roasting or chemical activation by pretreatment using 8 mol/L NaOh solution increases the total rEE recovery with significantly higher gains obtained for the light rEEs. Leaching kinetics are relatively fast within the first 2 h and then slow to provide relatively low overall recovery values under the standard test conditions for the coarse and fine reject samples. however, significantly higher recovery values are realized when treating mixed-phase(middling) particles existing within the coarse reject material.

关键词： Leaching Coal Thermal activation Chemical activation rare earth elements

Development of Generic Drug Products by Pharmaceutical Industries Considering regulatory Aspects: A review

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Journal of Biosciences and Medicines 2021年第10期9卷 23-39页

作者： md. Imtiaz hasan Shahnaz Akter Shimu Akhi Akther Ishrat Jahan md. hamiduzzaman A. h. M. Nazmul hasan Department of Pharmacy University of Asia Pacific Dhaka Bangladesh renata Limited Dhaka Bangladesh

Development of generic drug product by pharmaceutical industry is a scientific and technical approach which is totally different from developing a reference or innovator product. Most of the developing countries focus on developing the generic drug products because huge amount of investment is required for innovation and to develop reference product. The generic medicine has to be bioequivalent to the innovator drug and ensure the same biological effect with proper safety and efficacy. Nowadays, the pharmaceutical industries focus on the development of generic product as this does not require that much time and cost compared to the innovator company. But development of generic product is also difficult as it contains the same therapeutic efficacy as innovator. The development approach is based on the target market, i.e. US market, EU market. If a manufacturer targets the US market, then all excipients should be USP grade, analysis should be conducted by USP method or in-house method and stability studies as well. Prior and during the development of generic drug product API selection, dosage form selection, reference product selection and characterization, formulation development, analytical method development, tech transfer or submission batch are prime concern. Then again, bioequivalence study, drug registration procedure and commercialization of the generic product considering regulatory guidance of respective regulatory agencies and the approaches taken by the regulatory agencies for the development of registration of generic medicines are also crucial as well for the development of generic drug product. The aim of this study was to review the entire stage of a generic drug development by a generic pharmaceutical company.

关键词： Generic Drug reference Product Pre-Formulation NDA

Time-dependent lateral response of pile embedded in elasto-plastic soil

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Journal of Central South University 2010年第2期17卷 372-380页

作者： J.M.ABBAS Z.h.ChIK M.r.TAhA q.S.M.ShAFIqU Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia Department of Civil Engineering Nahrain University

A two-dimensional （2D） finite element analysis was carried out to assess the time-dependent behavior of single vertical pile embedded in elasto-plastic soil. The finite element analyses were carried out using the linear elastic model for the structure of the pile, while the Mohr-Coulomb model was used for representing the soil behavior surrounding the pile. The study includes cohesionless and cohesive soil to assess the lateral response of pile in the two types of soil. The whole geoteehnical model is suitable for problem of piles to determine the design quantities such as lateral deformation, lateral soil stress and its variation with time. The model is verified based on the results of published cases and there is good comparison between the results of published ease and the present simulation model. It is found that, the pile in cohesionless soil has more resistance in the rapid loading and less one in the long term loading. On the other hand, the pile in cohesive soil shows opposite behavior.

关键词： single pile consolidation effect lateral response soil pressure 2D finite element method

resistance Calculation of Pentagonal Lattice Structure of resistors

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Communications in Theoretical Physics 2019年第8期71卷 935-938页

作者： M.q.Owaidat J.h.Asad Department of Physics Al-Hussein Bin Talal University P.O. Box 20 Ma’an 71111 Jordan Department of Physics College of Applied Sciences Palestine Technical University P.O. Box 7 Tulkarm Palestine

In this study, the effective resistance between any two lattice sites in a two-dimensional pentagonal lattice structure of identical resistors is determined by means of the lattice Green’s function *** numerical resu... 详细信息

关键词： lattice Green’s function pentagonal lattice resistance numerical results

In VitroOrganogenesis of Colocasia esculentacv. AntiquorumL.

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American Journal of Plant Sciences 2012年第6期3卷 709-713页

作者： md. Jahangir hossain Bangladesh Agricultural research Institute Gazipur Bangladesh.

In vitro organogenesis of an upland species of Colocasia esculenta cv. antiquorum L. was examined in relation to different explants like meristem and parenchymatous storage tissues with or without anthocyanin layer, four levels of each of Kn, 2,4-D, NAA and BAP and four incubation environments such as: 1) 16 h 3 Kl light intensity + 24°C ± 2°C;2) 24 h dark + 24°C ± 2°C;3) 24 h dark + 30°C ± 3°C and 4) 12 h diffuse light + 30°C ± 3°C. Only meristems showed proliferation with various degree of intensity both at 16 h 3 Kl light + 24°C ± 2°C and 24 h dark + 24°C ± 2°C conditions and poor response with different levels of Kn + NAA either in light or in the dark. Cultures with NAA + BAP were proliferated very quickly with very high degree of intensity. The cultures under dark did not proliferate for 20 days which upon transfer to light showed high degree of proliferation. Cultures with NAA + BAP formed calluses more pronouncedly at dark than that occurred in the light. Parenchymatous tissues with or without anthocyanin did not proliferate but the tissues with anthocyanin lost pigmentation after 25 - 30 days and turned to grey colour after 50 days while tissues without anthocyanin turned to green colour with shinny pimples indicating that protocorm may be developed. No culture under high temperature environment (30°C ± 3°C) neither survived nor proliferated. The meristems in culture were died within 15 - 20 days while others within 25-30 days. In conclusion, a combination of NAA (0.5 - 3.0 mg/l) and BAP (0.5 - 2.0 mg/l) and an incubation photoperiod of 16 h coupled with temperature of 24°C ± 2°C were found most suitable for in vitro culture of Colocasia esculenta cv. antiquorum L.

关键词： Organogenesis Auxin Cytokinin Meristem Parenchymatous Storage Tissue In Vitro Colocasia esculenta cv. Antiquorum L

Influence of Fe Addition on Products of Self-Propagating high-Temperature Synthesis reaction in 3Ti-Si-2C System

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稀有金属材料与工程 2009年第A3期38卷 113-118页

作者： Guan q L Wang h Y Li S L Si W P Jiang q C Key Laboratory of Automobile Materials of Ministry of Education Jilin University Changchun 130025 China

Influence of Fe addition on products of self-propagating high-temperature synthesis (ShS) reaction in 3Ti-Si-2C system was investigated in the present study. Without Fe addition, Ti5Si3 and TiC are the dominant phases along with a small amount of Ti3SiC2 phase and unreacted C left in the final products. As Fe content ranges from 10% to 30%, the products consist of TiC, Ti5Si3, Fe2Ti and unreacted C, but no trace of Ti3SiC2 phase is detected. Furthermore, the amounts of both Fe2Ti and C phases increase with Fe content increasing. Addition of Fe has a great effect on the reaction route and significantly restrains the formation of Ti3SiC2 during the combustion synthesis process, and therefore, the ShS is not an effective fabrication technique to synthesize the ternary Ti3SiC2 ceramic in either 3Ti-Si-2C or Fe-3Ti-Si-2C system. Besides, without Fe addition, Ti5Si3 presents as the coarse irregular appearance with an obviously sintered morphology. In contrast, the shape of Ti5Si3 exhibits more and more spherical (cobblestone-like) and the surface becomes increasingly smooth, because the amount of liquids formed during the ShS reaction increases with the increase of Fe content. On the other hand, with Fe content increasing from 0 to 30 wt.%, the particulate size of TiC decreases from more than 5 μm to 1 μm or less, mainly due to the fact that the combustion temperature decreases with the increase of Fe content in the preforms.

关键词：复合材料铁含量燃烧过程物理性能

EMBrITTLEMENT OF A Cr-Mo LOW-ALLOY STEEL DUE TO LOW-TEMPErATUrE NEUTrON IrrADIATION

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 20-26页

作者： S.h. Song L. q. Weng Department of Materials Science and Engineering Shenzhen Graduate School HarbinInstitute of Technology Shenzhen 518055 China

Embrittlement of a Cr-Mo2.25CrlMo steel stemming from neutron irradiation at 270℃ is studied by virtue of small punch testing in conjunction with scanning electron microscopy. The ductile-brittle transition temperature determined by the small punch test is much lower than that determined by the standard Charpy test. There is some irradiation-induced embrittlement effect after the steel is irradiated for 46 days with a neutron dose rate of 1.05×10^18dpa/s （displacement per atom per second）.

关键词： irradiation embrittlement segregation low alloy steels pressure vessel

A TD-DFT Study for the Excited State Calculations of Microhydration of N-Acetyl-Phenylalaninylamide (NAPA)

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Computational Chemistry 2023年第2期11卷 37-52页

作者： md. Alauddin Joya Datta ripa Department of Theoretical and Computational Chemistry University of Dhaka Dhaka-1000 Bangladesh

Investigating the impact of microhydration on the excited-states and electronic excitation properties of biomolecules has remained one of the important yet challenging aspects of science because of the complexity of developing models. however, with the advent of computational chemistry methods such as TD-DFT, many useful insights about the electronic excitation energy and excited-state nature of biomolecules can be explored. Accordingly, in our study, we have incorporated the TD-DFT/wB97XD/cc-pVTZ method to study the excited state properties of N-acetyl phenylalanine amide (NAPA-A(h2O) n) (n = 1 to 4) clusters from ground to the tenth lowest gaseous singlet excited state. We found that the C=O bond length gradually increases both in N-terminal amide and C-terminal amide after the sequential addition of water molecules because of intermolecular h-bonding and this intermolecular h-bonding becomes weaker after the sequential addition of h2O molecules. The UV absorption maxima of NAPA-A (h2O)n (n = 1 - 4) clusters consisted of two peaks that are S5←S0 (1st absorption) and S6←S0 (2nd absorption) excitations. The first absorption maxima were blue-shifted with the increase in oscillator strength. This means that strong h-bonds reduce the charge transfer and make clusters more rigid. On the other hand, the second absorption maxima were red-shifted with the decrease in oscillator strength. In the ECD spectra, the negative bands indicate the presence of an amide bond and L-configuration of micro hydrated NAPA-A clusters. Finally, our calculated absorption and fluorescence energy confirm that all the NAPA-A (h2O) n (n = 0 - 4) clusters revert to the ground state from the fluorescent state by emitting around 5.490 eV of light.

关键词： Excited State h-Bonding Micro hydration Absorption and Fluorescence Energy