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Chinese journal of Structural Chemistry 2013年第8期32卷 1143-1152页

作者： Arvids Stashansa Soraya jácome Grupo de Fisicoquímica de Materiales Universidad Técnica Particular de Loja Escuela de Ingeniería Química Universidad Técnica Particular de Loja

Using the first-principles density functional theory calculations within the genera- lized gradient approximation we study the bis（1H-imidazolium-kN3）silver（I） nitrate molecular crystal. A number of different exchange-correlation functionals are considered for a possible treatment of the system. Perdew-Burke-Emzerhof （PBE） GGA exchange-correlation ftmctionals are found to be adequate for our system. The obtained results show that it is possible to reproduce very well the geometry of at least some molecular crystals if computational parameters are chosen adequately. In addition to the reproducing crystal structure of the bis（1H-imidazolium-kN3）silver（I） nitrate in close agreement with the available experimental data, the present work reports analysis on the chemical bonding in the material and gives total and partial density of states of this system.

关键词： crystal structure electronic properties chemicalbonding density functional theory

Three Phase Composite Cylinder Assemblage Model for Analyzing the Elastic Behavior of MWCNT-reinforced Polymers

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Computers, Materials & Continua 2018年第1期54卷 1-20页

作者： Puneet Kumar j.Srinivas research Scholar Mechanical Engineering DepartmentNational Institute of Technology RourkelaOdisha-769008India Associate Professor Mechanical Engineering DepartmentNational Institute of Technology RourkelaOdisha-769008India

Evolution of computational modeling and simulation has given more emphasis on the research activities related to carbon nanotube(CNT)reinforced polymer composites *** paper presents the composite cylinder assemblage(CCA)approach based on continuum mechanics for investigating the elastic properties of a polymer resin reinforced by multi-walled carbon nanotubes(MWCNTs).A three-phase cylindrical representative volume element(rVE)model is employed based on CCA technique to elucidate the effects of inter layers,chirality,interspacing,volume fraction of MWCNT,interphase properties and temperature conditions on the elastic modulus of the *** interface region between CNT and polymer matrix is modeled as the third phase with varying material *** constitutive relations for each material system have been derived based on solid mechanics and proper interfacial traction continuity conditions are *** predicted results from the CCA approach are in well agreement with rVE-based finite element *** outcomes reveal that temperature softening effect becomes more pronounced at higher volume fractions of CNTs.

关键词： Multi-walled carbon nanotube composite cylinder assemblage continuum representative volume element variable interphase

INTErACTIONS BETWEEN KETONES AND AMINES IN PHOTOINITIATING SYSTEMS USED FOr rADICAL POLYMErIZATION

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Chinese journal of Polymer Science 1990年第1期8卷 51-60页

作者：吴世康 FOUASSIEr j.P. Laboratoire

Time resolved laser spectroscopy and GC/MS were used to investigate the primary processes and the side reactions occurring in benzophenone and chlorothioxanthone/amine systems used as photoinitiators of radical polymerization. The discrepancy observed between the experimental data and the expected behaviour is accounted for by detrimental chemical reaction involving the ketone triplet state, the ketyl radical and the amine-derived radical.

关键词： Photoinitiating systems photopolymerization Benzophenone/Amine system Chlorothioxanthone/Amine system Light absorbing transient (LAT).

Three-dimensional CityGML building models in mobile augmented reality: a smartphone-based pose tracking system

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International journal of Digital Earth 2021年第1期14卷 32-51页

作者： Christoph Blut jörg Blankenbach Geodetic Institute Department of Computing in Civil Engineering and Geo-Information SystemsRWTH Aachen UniversityAachenGermany

Many augmented reality(Ar)systems are developed for entertainment,but Ar and particularly mobile Ar potentially have more application possibilities in other *** example,in civil engineering or city planning,Ar could be used in combination with CityGML building models to enhance some typical workflows in planning,execution and operation processes.A concrete example is the geo-referenced on-site visualization of planned buildings or building parts,to simplify planning processes and optimize the communication between the participating *** of the main challenges for the visualization lies in the pose tracking,*** real-time estimation of the translation and rotation of the mobile device to align the virtual objects with *** this paper,we introduce a proof-of-concept fine-grained mobile Ar CityGML-based pose tracking system aimed at the mentioned *** system estimates poses by combining 3D CityGML data with information derived from 2D camera images and an inertial measurement unit and is fully self-sufficient and operates without external *** results of our evaluation show that CityGML and low-cost off-the-shelf mobile devices,such as smartphones,already provide performant and accurate mobile pose tracking for Ar in civil engineering and city planning.

关键词： Mobile augmented reality pose tracking CityGML 3D city model Android smartphone

A noninteracting control strategy for the robust output synchronization of linear heterogeneous networks

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Control Theory and Technology 2014年第3期12卷 234-249页

作者： Saman KHODAVErDIAN jürgen ADAMY Institute of Automatic Control and Mechatronics Control Methods and Robotics Lab Technische Universitt DarmstadtLandgraf-Georg-Str.464283 Darmstadt Germany

This paper deals with the problem of robust output synchronization for heterogeneous multi-agent systems. First, a new synchronization approach is presented to synchronize the outputs of heterogeneous agents. Based on noninteracting control techniques, a method is derived for homogenizing the input-output behavior of every agent. Hence, applying the same reference input signal to every agent leads to synchronization. Furthermore, a strategy for increasing the robustness of the synchronization process against exogenous disturbances is presented, which leads to a structurally constrained optimization problem. However, by a convenient reformulation of the problem, well established tools from robust control theory can be used. Moreover, it is shown that this procedure allows to separate the robustness issue from the synchronization task. The effectiveness of the approach is illustrated by a robust output synchronization example for a heterogeneous aircraft fleet.

关键词： Heterogeneous networks Multi-agent systems Decentralized control robust synchronization Disturbance rejection Controller constraints and structure

Tanning capacityof Tessmannia burttii extracts:thepotentialeco-friendlytanning agents fortheleatherindustry

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journal of Leather Science and Engineering 2021年第1期3卷 149-157页

作者： Cecilia r.China Stephen S.Nyandoro joan j.E.Munissi Mihayo M.Maguta Michael Meyer Michaela Schroepfer Division of Textile and Leather Technologies Tanzania Industrial Research and Development OrganizationP.O.Box 2355Dar es SalaamTanzania Chemistry Department College of Natural and Applied SciencesUniversity of Dar es SalamP.O.Box 35061Dar es SalaamTanzania Department of Environmental Planning Institute of Rural Development Planning(IRDP)P.O.Box 138DodomaTanzania FILK-research Institute of Leather and Plastic Sheeting Meißner Ring 1-509599 FreibergGermany

In the present study,the tannins from stem and root barks of Tessmannia burttii Harms(Caesalpiniaceae),a plant species abundantly growing in Tanzania and other parts of Africa,were investigated for their suitability in hides *** powder was extracted at selected temperatures(30,50 and 80°C)and the influence of each temperature on the crosslinking capacity was *** interaction mechanism between hide powder collagen and the tannins was studied by Differential Scanning Calorimetry(DSC),trinitrobenzensulfonic(TNBS)acid assay and amino acid hydrolysis *** temperatures showed low influence on crosslinking capacity of the ***,extract obtained at 50°C exhibited best performance in terms of gap size between T onset and T *** stem bark extract yield was higher than that from the root bark,but both were within the recommended *** tannin content(61%)of *** stem bark extract was above recommended value(10%),whereas its total phenolic content and total flavonoic content were found to be above that of commercial Acacia mearnsii *** study of cross-linking parameters as a function of pH showed cross-linking to occur via a covalent mechanism at the basic amino ***,the bonds were not resistant to acid *** observed interaction mechanism indicated that tannins from stem and root barks of *** belong to the condensed tannin,similar to ***(black wattle),a commercial tannin source that was used in this study as a *** from this study depict that *** extracts are auspicious eco-friendly alternative source of vegetable tannins to overcome the use of chromium salts in the leather industry.

关键词： Tessmannia burttii Caesalpiniaceae Leather industry Vegetable tanning Tanning capacity

On the Bloch Constant for K-Quasiconformal Mappings in Several Complex Variables

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Acta Mathematica Sinica,English Series 2001年第2期17卷 237-242页

作者： j. Y. GAMALIEL Department of Mathematics. Nanjing Normal University. Nanjing 210097. P. r. China

We study the Bloch constant for K-quasiconformal holomorphic mappings of the unit ball B of Cn into Cn. The final result we prove in this paper is: If f is a K-quasiconformal holomorphic mapping of B into Cn such that det（f’（0））=1, then f（B） contains a schlicht ball of radius at least （CnK）1-n integral from n=0 to 1(（1+t）n-1/（1-t）2 exp{-（n+1）t/（1-t）}dt, where Cn>1 is a constant depending on n only, and Cn→101/2 as n→∞.

关键词： K-quasiconformal mapping Bloch constant

The Triple Combination of Meropenem,Avibactam,and a Metallo-β-Lactamase Inhibitor Optimizes Antibacterial Coverage Against Different β-Lactamase Producers

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Engineering 2024年第7期38卷 124-132页

作者： Zhuoren Ling Alistair james Macdonald Farley Aditya Lankapalli Yanfang Zhang Shonnette Premchand-Branker Kate Cook Andrei Baran Charlotte Gray-Hammerton Claudia Orbegozo rubio Edgars Suna jordan Mathias jürgen Brem Kirsty Sands Maria Nieto-rosado Maria Mykolaivna Trush Nadira Naznin rakhi Willames Martins Yuqing Zhou Christopher joseph Schofield Timothy Walsh Department of Biology&Ineos Oxford Institute for Antimicrobial research University of OxfordOxford OX13REUK Chemistry research Laboratory Department of Chemistry and the Ineos Oxford Institute for Antimicrobial ResearchUniversity of OxfordOxford OX13TAUK Latvian Institute of Organic Synthesis Riga LV-1006Latvia Department of Medical Microbiology Division of Infection and ImmunitySchool of MedicineCardiff UniversityCardiff CF144XNUK Enzymology and Applied Biocatalysis research Center Faculty of Chemistry and Chemical EngineeringBabes-Bolyai UniversityCluj-Napoca 400028Romania

This work explores the potential of a triple combination of meropenem(MEM),a novel metallo-blactamase(MBL)inhibitor(indole-2-carboxylate 58(InC58)),and a serine-b-lactamase(SBL)inhibitor(avibactam(AVI))for broad-spectrum activity against carbapenemase-producing bacteria.A diverse panel comprising MBL-and SBL-producing strains was used for susceptibility testing of the triple combination using the agar dilution *** frequency of resistance(For)to MEM combined with InC58 was *** were sequenced and tested for cross resistance,fitness,and the stability of the resistance *** with the double combinations of MEM plus an SBL or MBL inhibitor,the triple combination extended the spectrum of activity to most of the isolates bearing SBLs(oxacillinase-48(OXA-48)and Klebsiella pneumoniae carbapenemase-2(KPC-2))and MBLs(New Delhi metallo-blactamases(NDMs)),although it was not effective against Verona integron-encoded metallo-blactamase(VIM)-carrying Pseudomonas aeruginosa(***)and OXA-23-carrying Acinetobacter baumannii(***).The For to MEM plus InC58 ranged from 2.22×10^(-7)to 1.13×10^(-6).The resistance correlated with mutations to ompC and comr,affecting porin C and copper permeability,*** mutants manifested a fitness cost,a decreased level of resistance during passage without antibiotic pressure,and cross resistance to another carbapenem(imipenem)and a b-lactamase inhibitor(taniborbactam).In conclusion,compared with the dual combinations,the triple combination of MEM with InC58 and AVI showed a much wider spectrum of activity against different carbapenemaseproducing bacteria,revealing a new strategy to combat b-lactamase-mediated antimicrobial resistance.

关键词： Carbapenemase Metallo/serine-b-lactamase inhibitor Avibactam Meropenem Antimicrobial resistance

Means, Advantages and Limits of Merging Biology with Technology

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journal of Bionic Engineering 2004年第2期1卷 121-132页

作者： O. A. Bogatyreva A.-K. Pahl. N.r. Bogatyrev j.F.V. Vincent Centre for Biomimetic and Natural Technologies Department of Mechanical Engineering the University of Bath BA2 7AY UKCentre for Biomimetic and Natural Technologies Department of Mechanical Engineering the University of Bath BA2 7AY UKCentre for Biomimetic and Natural Technologies Department of Mechanical Engineering the University of Bath BA2 7AY UKCentre for Biomimetic and Natural Technologies Department of Mechanical Engineering the University of Bath BA2 7AY UK

The natural world spent billions of years in solution-finding during evolution, which could benefit Technology. How do we put that in a nutshell? Biological systems are more complex than the most complex current technology. Any given function and effect are simultaneously coordinated and linked with others at many levels of biological organisation-from cell organelle to organism, to population and ecosystem. Technology does not have tools to deal with the complexity and “goal-intendedness” of living systems. But limits for interaction exist on both sides-Biological science itself is also too empirical and not mature enough to provide a solid base for correlating living with technical systems. Moving towards a synthesis, where engineers can utilize the vast amount of available biological data, we suggest using a tool called “Theory of Inventive Problem Solving” (TrIZ) and clarifying some important methodological issues, which have not previously been recognised in bionic engineering: 1) requirement for more appropriate definitions of “system”, “effect”, “function”,“law” and “rule”. 2) requirement for understanding or even measuring the degree of contradiction or analogy between functions in biological and artificial and/or non-living engineering system-there is no simple direct correlation between what engineers find useful and what biology does.

关键词： technology TrIZ biological effect contradiction science methodology

Non-classical phenotypes of autoimmune hepatitis and advances in diagnosis and treatment

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World journal of Gastroenterology 2009年第19期15卷 2314-2328页

作者： Albert j Czaja Yusuf Bayraktar Division of Gastroenterology and Hepatology Mayo Clinic College of MedicineRochesterMinnesotaUnited States and the Department of GastroenterologyHacettepe University School of MedicineAnkara 06100Turkey

Non-classical manifestations of autoimmune hepatitis can delay diagnosis and treatment. Our aims were to describe the clinical phenotypes that can confound the diagnosis, detail scoring systems that can ensure their recognition, and outline advances in treatment that can improve their outcome. Prime source and review articles in English were selected throuqh Medline from 1970-2008 and assimilated into personal libraries spanning 32 years. Acute severe or asymptomatic presentations and atypical histological findings,including centrilobular zone 3 necrosis and concurrent bile duct changes, are compatible with the diagnosis. Cholangiographic abnormalities may be present in children and adults with the disease, and autoimmune hepatitis must be considered in patients without autoantibodies or with antimitochondrial antibodies and no other cholestatic features. Asymptomatic patients frequently become symptomatic; mild disease can progress; and there are no confident indices that justify withholding treatment. Two diagnostic scoring systems with complementary virtues have been developed to evaluate patients with confusing features. Normal liver tests and tissue constitute the optimal end point of treatment, and the first relapse is an indication for long- term azathioprine therapy. Cyclosporine, tacrolimus and mycophenolate mofetil are promising salvage therapies,and budesonide with azathioprine may be a superior frontline treatment. We conclude that the non-classical phenotypes of autoimmune hepatitis can be recognized promptly, diagnosed accurately, and treated effectively.

关键词： Non-classical phenotypes Scoring systems Treatment strategies