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Journal of Rock Mechanics and Geotechnical Engineering 2016年第1期8卷 93-112页

作者： Mohsen s.Masoudian school of Civil Engineering University of SydneyDarlingtonAustralia

To reduce the emissions of carbon dioxide(CO) into the atmosphere, it is proposed to inject anthropogenic COinto deep geological formations. Deep un-mineable coalbeds are considered to be possible COrepositories because coal is able to adsorb a large amount of COinside its microporous ***, the response of coalbeds is complex because of coupled flow and mechanical processes. Injection of COcauses coal to swell, which leads to reductions in permeability and hence makes injection more difficult, and at the same time leads to changes in the mechanical properties which can affect the stress state in the coal and overlying strata. The mechanical properties of coal under storage conditions are of importance when assessing the integrity and safety of the storage scheme. On the other hand, the geomechanical response of coalbed will also influence the reservoir performance of coalbed. This paper provides an overview of processes associated with coalbed geosequestration of COwhile the importance of geomechanical characteristics of coalbeds is highlighted. The most recent findings about the interactions between gas transport and geomechanical characteristics of coal will be discussed and the essence will be delivered. The author suggests areas for future research efforts to further improve the understanding of enhanced coalbed methane(ECBM) and coalbed geosequestration of CO.

关键词： Coalbed geosequestration Carbon dioxide(CO_2) Reservoir geomechanics Elasticity Rock failure

Discipline Impact Factor: some of Its History, some of the Author's Experience of Its Application, the Continuing Reasons for Its Use and… Next Beyond

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Journal of Data and Information science 2020年第3期5卷 197-209页

作者： Vladimir s.Lazarev Belarusian National Technical University 16 Yakub Kolas StMinsk220013Republic of Belarus

Purpose: This work aims to consider the role and some of the 42-year history of the discipline impact factor(DIF) in evaluation of serial publications. Also, the original "symmetric" indicator called the "discipline susceptibility factor" is to be presented. Design/methodology/approach: In accordance with the purpose of the work, the methods are analytical interpretation of the scientific literature related to this problem as well as speculative explanations. The information base of the research is bibliometric publications dealing with impact, impact factor, discipline impact factor, and discipline susceptibility ***: Examples of the DIF application and modification of the indicator are given. It is shown why research and university libraries need to use the DIF to evaluate serials in conditions of scarce funding for subscription to serial publications, even if open access is available. The role of the DIF for evaluating journals by authors of scientific papers when choosing a good and right journal for submitting a paper is also briefly discussed. An original indicator "symmetrical" to the DIF(the "discipline susceptibility factor") and its differences from the DIF in terms of content and purpose of evaluation are also briefly *** limitations: The selection of publications for the information base of the research did not include those in which the DIF was only mentioned, used partially or not for its original purpose. Restrictions on the length of the article to be submitted in this special issue of the JDIs also caused exclusion even a number of completely relevant publications. Consideration of the DIF is not placed in the context of describing other derivatives from the Garfield impact factor. Practical implications: An underrated bibliometric indicator, viz. the discipline impact factor is being promoted for the practical application. An original indicator "symmetrical" to DIF has been proposed in order of searching serial publicatio

关键词： Discipline impact factor Discipline susceptibility factor Citation analysis Journals evaluation serials evaluation Information service

Organocatalyzed Decarboxylation of Naturally Occurring Cinnamic Acids: Potential Role in Flavoring Chemicals Production

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Open Journal of Physical Chemistry 2011年第3期1卷 85-93页

作者： Virginia Aldabalde María Lucía Derrudi Daniela Gamenara Federico Geymonat Patricia saenz-Méndez Mariela Risso Gustavo seoane 不详

The mechanism and the final outcome of the Knoevenagel-Doebner reaction are discussed. The condensation reaction between different hydroxy-substituted aromatic aldehydes and malonic acid is performed using piperidine as organocatalyst. The key role of the catalyst is clearly pointed out during the decarboxylation of ferulic acid, without the use of a strong decarboxylating agent, leading to a 4-vinylphenol derivative. Based on the results obtained, the studied pathway may be important in the understanding of vinylphenol production during malting and brewing of wheat and barley grains. Finally, changing the solvent of the reaction from pyridine to water in the Knoevenagel-Doebner reaction of 4-hydroxybenzaldehydes, dimerization of resulting styrene derivatives is observed. These results can be of interest also in the field of food chemistry, since cinnamic acids are frequently found in fruits and vegetables used for human consumption.

关键词： β-Unsaturated Carboxylic Acids Decarboxylation Vinylphenols Organocatalysis Knoevenagel

Evaluation of management tools for the control of poplar leaf defoliators (Lepidoptera: notodontidae) in northwestern India

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Journal of Forestry Research 2011年第1期22卷 77-82页

作者： K.s. sangha Department of Forestry and Natural Resources Punjab Agricultural University Ludhiana Punjab India

Populus suffers from multiple insect damage throughout its distributional range in northwestern India. The evaluation of various management tools was done based on the hypothesis that manipulation of insect habitat can provide tangible results. Manipulation of cultural practices, ploughing of field during December, and growing of crops （wheat, Trifolium alexandrinum and others） results in lower adult emergence, reduced leaf infestation, number of larvae and pupae per meter branch length of poplar leaf defoliators （PLD）. Fallow plantations were more prone to attack of PLD than intercropped plantations. Higher incidence of Clostera restitura was recorded in southwestern dry zones due to unsuitability of the site, poor quality of irrigation water and dry weather conditions. Complete stripping of Populus trees does not occur in low temperature ＆ high humidity, submountaneous zones of Punjab. Chemical control studies were conducted in laboratory ＆ field conditions, and among the five insecticides tested, Profenophos 50 EC, Quinalphos 25 EC and Carbaryl 50 WP @ 0.05 and 0.1 percent concentration gave consistently high mortality of PLD larvae up to 21 days after spraying. Use of insecticides prior to peak activity periods ＆ during evening hours enhances the efficiency of management options.

关键词： abundance control Clostera sp. distribution Populus

static and dynamic responses of a microcantilever with a T-shaped tip mass to an electrostatic actuation

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Acta Mechanica sinica 2016年第6期32卷 1104-1122页

作者： B.Firouzi M.Zamanian s.A.A.Hosseini Department of Mechanical Engineering Faculty of Engineering Kharazmi University

In this study, nonlinear static and dynamic responses of a microcantilever with a T-shaped tip mass excited by electrostatic actuations are investigated. The electrostatic force is generated by applying an electric voltage between the horizontal part of T-shaped tip mass and an opposite electrode plate. The cantilever microbeam is modeled as an Euler-Bernoulli beam. The T-shaped tip mass is assumed to be a rigid body and the nonlinear effect of electrostatic force is considered. An equation of motion and its associated boundary conditions are derived by the aid of combining the Hamilton principle and Newton’s method. An exact solution is obtained for static deflection and mode shape of vibration around the static position. The differential equation of nonlinear vibration around the static position is discretized using the Galerkin method. The system mode shapes are used as its related comparison functions. The discretized equations are solved by the perturbation theory in the neighborhood of primary and subharmonic resonances. In addition, effects of mass inertia, mass moment of inertia as well as rotation of the T-shaped mass, which were ignored in previous works, are considered in the analysis. It is shown that by increasing the length of the horizontal part of the T-shaped mass, the amount of static deflection increases, natural frequency decreases and nonlinear shift of the resonance frequency increases. It is concluded that attaching an electrode plate with a T-shaped configuration to the end of the cantilever microbeam results in a configuration with larger pull-in voltage and smaller nonlinear shift of the resonance frequency compared to the configuration in which the electrode plate is directly attached to it.

关键词： MEMs Electrostatic static deflection Natural frequency Pull-in voltage Perturbation theory T-shaped mass Primary and subharmonic resonances

Fabrication of chitosan/silica hybrid coating on AZ31 Mg alloy for orthopaedic applications

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Journal of Magnesium and Alloys 2023年第2期11卷 614-628页

作者： M.Kalaiyarasan s.Pugalmani N.Rajendran Department of Chemistry CEG CampusAnna UniversityChennai600025Tamil NaduIndia Department of Orthodontics Saveetha Dental College and HospitalsSaveetha Institute of Medical and Technical ScienceSaveetha UniversityChennai-600077India

Biocompatible conversion of chitosan and chitosan/silica hybrid coating were prepared to enhance the biocompatibility and corrosion resistance of biodegradable AZ31 Mg alloy. The coatings were optimized and analysed with potentiodynamic polarization, sEM, ATR-IR and XPs studies. Potentiodynamic polarization studies, revealed that the coatings exhibited high corrosion resistance. The surface morphology of the Ch-3/si coating showed small globular rough structure. The presence of functional groups was confirmed by ATR-IR. For a better understanding of chitosan/silica hybrid coating, the chemical states were examined by XPs studies. The in-vitro bioactivity of the coated samples was evaluated in Earle’s solution, which formed a dense layer of coral-like structure and calcium-deficient apatite with less stoichiometric ratio than the hydroxyapatite. In-vitro cell culture studies exhibited a good cell proliferation rate and the fabricated Ch-3/si coating was found to be non-hemolytic. The bacterial studies proved that Ch-3/si coating possessed inherent antibacterial activity.

关键词： AZ31 Mg alloy Chitosan/silica Hemocompatibility MTT assay and antibacterial studies

Analyzing variations in spatial critical gaps at two-way stop controlled intersections using parametric and non-parametric techniques

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第1期8卷 129-138页

作者： Digvijay s.Pawar Gopal R.Patil Department of Civil Engineering Indian Institute of Technology HyderabadKandi 502285India Department of Civil Engineering Indian Institute of Technology BombayPowai 400076India

At two-way stop controlled(TWsC)intersections drivers on minor stream are generally at risk because of the difficulty in judging safe gap between major stream *** misjudgment by the driver while choosing gap may result in a collision with major stream *** paper provides important insights for determining and analyzing spatial critical gaps of drivers at high speed and medium speed TWsC *** critical gap line(CGL)fitted for the accepted and rejected gaps using parametric(binary logit model-BLM)and non-parametric(support vector machines-sVM)techniques gives critical gap values at 15 th,50 th and 85 th percentile *** evaluation of spatial critical gap with respect to major road vehicle(conflicting vehicle)speed makes it easier to understand the impact of variation in speed on spatial gaps accepted by the drivers on the minor *** logit models developed revealed that the probability of accepting gap decreases with increase in the speed of the conflicting vehicle and it increases with increase in the distance of conflicting *** spatial critical gaps estimated using support vector machines were found in close approximation with those estimated using binary logit *** study results showed that sVMs have very good potential to be an alternative tool for the estimation of driver's critical *** spatial critical gaps corresponding to 15 th,50 th and 85 th percentile speeds for medium speed intersections were 32 m,38 m and 46 m respectively and for high speed intersections these values were 64 m,76 m and 104 m *** increase in the magnitude of gap value with respect to the percentile speed clearly states the effect of speed on spatial *** insights from the study can be used to suggest various measures to improve the safety of crossing drivers at uncontrolled intersections.

关键词： Traffic engineering spatial critical gaps Uncontrolled intersections Logit model sVM Driver behavior

Ground state energy of He isoelectronic sequence treated variationally via Hylleraas-like wavefunction

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Chinese Physics B 2009年第6期18卷 2238-2243页

作者： serpil sakiroglu Kadir Akgngr Ismail skmen Physics Department Dokuz Eyll University

In this study, the energy for the ground state of helium and a few helium-like ions （Z=1-6） is computed variationally by using a Hylleraas-like wavefunction. A four-parameters wavefunction, satisfying boundary conditions for coalescence points, is combined with a Hylleraas-like basis set which explicitly incorporates r12 interelectronic distance. The main contribution of this work is the introduction of modified correlation terms leading to the definition of integral transforms which provide the calculation of expectation value of energy to be done analytically over single-particle coordinates instead of Hylleraas coordinates.

关键词： He isoelectronic sequence Hylleraas basis set electronic correlation variational method

Time gap for temporal cloak based on spectral hole burning in atomic medium

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Chinese Physics B 2016年第8期25卷 175-180页

作者： Abdul Jabar M s Bakht Amin Bacha Iftikhar Ahmad Department of Physics University of Malakand

We demonstrate the possibility of creating a time gap in the slow light based on spectral hole burning in a fourlevel Doppler broadened sodium atomic system. A time gap is also observed between the slow and the fast light in the hole burning region and near the burnt hole region, respectively. A cloaking time gap is attained in microseconds and no distortion is observed in the transmitted pulse. The width of the time gap is observed to vary with the inverse Doppler effect in this system. Our results may provide a way to create multiple time gaps for a temporal cloak.

关键词： temporal cloak susceptibility slow and fast light spectral holes

CR deformations for rational homogeneous surface singularities

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science China Mathematics 2005年第Z1期48卷 74-85页

作者： John s.Bland Department of Mathematics University of Toronto TorontoM5S 3G3Canada

In this paper, we will present a CR-construction of the versal deformations of the singularities Vn (～- )C2/Zn, n ∈ {2, 3, 4,…} defined by the immersions of C2 into Cn+1Xn: (z,w) → (zn,zn-1w,…,zwn-1,wn).

关键词： CR deformation, obstruction.