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Communications in Computational Physics 2009年第1期5卷 126-141页

作者： junqi Huang Aihua W.Wood Michael j.Havrilla Air Force Institute of Technology 2950 Hobson WayWright-Patterson AFBOH 45433USA

A hybrid finite element-Laplace transform method is implemented to analyze the time domain electromagnetic scattering induced by a 2-D overfilled cavity embedded in the infinite ground *** algorithm divides the whole scattering domain into two,interior and exterior,*** the interior sub-domain which covers the cavity,the problem is solved via the finite element *** problem is solved analytically in the exterior sub-domain which slightly overlaps the interior subdomain and extends to the rest of the upper half *** use of the Laplace transform leads to an analytical link condition between the overlapping *** analytical link guides the selection of the overlapping zone and eliminates the need to use the conventional Schwartz *** dramatically improves the efficiency for solving transient scattering *** solutions are tested favorably against analytical ones for a canonical *** perfect link over the artificial boundary between the finite element approximation in the interior and analytical solution in the exterior further indicates the reliability of the *** error analysis is also performed.

关键词： Overfilled cavity time domain electromagnetic scattering Laplace transform finite element method

Hybrid polymer biomaterials for bone tissue regeneration

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Frontiers of Medicine 2019年第2期13卷 189-201页

作者： Bo Lei Baolin Guo Kunal j.Rambhia Peter X.Ma Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710054China Department of Biomedical Engineering University of MichiganAnn ArborMI 48109USA Department of Biologic and Materials Sciences University of MichiganAnn ArborMI 48109USA Macromolecular Science and Engineering Center University of MichiganAnn ArborMI 48109USA Department of Material Science and Engineering University of MichiganAnn ArborMI 48109USA

Native tissues possess unparalleled physiochemical and biological functions, which can be attributed to their hybrid polymer composition and intrinsic bioactivity. However, there are also various concerns or limitations over the use of natural materials derived from animals or cadavers, including the potential immunogenicity, pathogen transmission, batch to batch consistence and mismatch in properties for various applications. Therefore, there is an increasing interest in developing degradable hybrid polymer biomaterials with controlled properties for highly efficient biomedical applications. There have been efforts to mimic the extracellular protein structure such as nanofibrous and composite scaffolds, to functionalize scaffold surface for improved cellular interaction, to incorporate controlled biomolecule release capacity to impart biological signaling, and to vary physical properties of scaffolds to regulate cellular behavior. In this review, we highlight the design and synthesis of degradable hybrid polymer biomaterials and focus on recent developments in osteoconductive, elastomeric, photoluminescent and electroactive hybrid polymers. The review further exemplifies their applications for bone tissue regeneration.

关键词： hybrid polymer bone regeneration tissue engineering biomaterials

A new way to construct topological invariants of non-Hermitian systems with the non-Hermitian skin effect

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Chinese Physics B 2020年第1期29卷 119-123页

作者： j S Liu Y Z Han C S Liu Hebei Key Laboratory of Microstructural Material Physics School of ScienceYanshan UniversityQinhuangdao 066004China

The non-Hermitian skin effect breaks the conventional bulk–boundary correspondence and leads to non-Bloch topological *** by the fact that the topological protected zero modes are immune to perturbations,we construct a partner of a non-Hermitian system by getting rid of the non-Hermitian skin *** adjusting the imbalance hopping,we find that the existence of zero-energy boundary states still dictate the bulk topological invariants based on the band-theory *** non-Hermitian Su–Schrieffer–Heeger(SSH)models are used to illuminate the ***,we obtain the winding numbers in analytical form without the introduction of the generalized Brillouin *** work gives an alternative method to calculate the topological invariants of non-Hermitian systems.

关键词： non-Hermitian skin effect Su–Schrieffer–Heeger(SSH)model bulk–boundary correspondence topological invariant

Co_(3)Mo_(3)N—An efficient multifunctional electrocatalyst

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The Innovation 2021年第2期2卷 40-46页

作者： Yao Yuan Samira Adimi Tiju Thomas jiacheng Wang Haichuan Guo jian Chen j.Paul Attfield Francis j.DiSalvo Minghui Yang Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo315201China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian116023China Department of Metallurgical and Materials Engineering Indian Institute of Technology Madras AdyarChennai 600036Tamil NaduIndia State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Centre for Science at Extreme Conditions and School of Chemistry University of EdinburghEdinburghEH93JZUK Department of Chemistry and Chemical Biology Cornell UniversityNew York14853USA

Efficient catalysts are required for both oxidative and reductive reactions of hydrogen and oxygen in sustainable energy conversion ***,current precious metal-based electrocatalysts do not perform well across the full range of reactions and reported multifunctional catalysts are all complex ***,we show that singlephase porous Co3Mo3N prepared via a facile method is an efficient and reliable electrocatalyst for three essential energy conversion reactions;oxygen evolution reaction(OER),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER)in alkaline ***3-Mo3N presents outstanding OER,ORR,and HER activity with high durability,comparable with the commercial catalysts RuO2 for OER and Pt/C for ORR and *** practical demonstrations,Co3Mo3N gives high specific capacity(850 mA h gZn^(-1) at 10 mA cm^(-2))as the cathode in a zinc-air battery,and a low potential(1.63 V at 10 mA cm^(-2))used in a water-splitting *** of Co and Mo d-states appear to result in high ORR and HER performance,while the OER properties result from a cobalt oxide-rich activation surface *** findings will inspire further development of bimetallic nitrides as cost-effective and versatile multifunctional catalysts that will enable scalable usage of electrochemical energy devices.

关键词： ternary nitrides multifunctional electrocatalysts rechargeable Zn-air batteries water splitting

Roles of manganese in photosystem II dynamics to irradiations and temperatures

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Frontiers in Biology 2013年第3期8卷 312-322页

作者： Xuejing HOU Harvey j. M. HOU Department of Chemistry and Biochemistry University of Massachusetts Dartmouth North Dartmouth MA 02747 USA Department of Physical Sciences Alabama State University Montgomery AL 36104 USA

The most amazing chemistry is the light-driven water splitting reaction occurred in the oxygen-evolving complex of phototsystem II in higher plants, green algae, and cyanobacteria. Mn, in the form of Mn4CaOs cluster in photosystem II, is responsible for the catalytic water splitting reaction as well as plays roles in photosystem II dynamics to irradiation and temperatures. Manganese hypothesis of UV-initiated photoinhibition as a direct target is established, and thermal inactivation of photosystem II involves the valence and structural changes of manganese. Recent progresses in understanding the roles of manganese in photoinhibition especially under UV light and in thermal inactivation including elevated temperatures using synthetic models and native PS II complexes are summarized and evaluated. Potential problems and possible solutions are discussed and presented.

关键词： photosynthesis manganese photosystem II irradiation temperature stress

Determination of Neutron Irradiation-Induced Phosphorus Segregation on Grain Boundaries in a P-doped 2.25Cr1Mo Steel

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journal of Materials Science & Technology 2004年第1期20卷 81-85页

作者： ShenhuaSONG R.G.Faulkner P.E.j.Flewitt DongdongSHEN jingLIU ZexiYUAN SchoolofMaterialsandMetallurgy WuhanUniversityofScienceandTechnologyWuhan430081China InstituteofPolymerTechnologyandMaterialsEngineering LoughboroughUniversityLoughboroughLeicestershireLEll3TUUK BerkeleyCentre BNFLMagnoxGenerationBerkeleyGloucestershireGL139PBUK

Irradiation-induced impurity segregation to grain boundaries is one of the important radiation effects on materials. For this reason, phosphorus segregation to prior austenite grain boundaries in a P-doped 2.25Cr1Mo steel subjected to neutron irradiation is examined using field emission gun scanning transmission electron microscopy (FEGSTEM) with energy dispersive X-ray microanalysis (EDX). The steel samples are irradiated around 270 and 400℃, respectively. The irradiation dose rate and dose are -1.05×10-8 dpa/s and -0.042 dpa respectively for 270℃ irradiation, and 1.7×10-8 dpa/s and 0.13 dpa respectively for 400℃ irradiation. The FEGSTEM results indicate that there is no apparent phosphorus segregation during 270℃ irradiation but there is some during 400℃ irradiation.

关键词： Neutron irradiation Segregation Grain boundary Phosphorus

Vertical response of microbial community and degrading genes to petroleum hydrocarbon contamination in saline alkaline soil

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journal of Environmental Sciences 2019年第7期31卷 80-92页

作者： Qinglong Liu jingchun Tang Xiaomei Liu Benru Song Meinan Zhen Nicholas j.Ashbolt College of Environmental Science and Engineering Nankai University Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education) Tianjin Engineering Research Center of Environmental Diagnosis and Contamination Remediation School of Public Health University of Alberta

A column microcosm was conducted by amending crude oil into Dagang Oilfield soil to simulate the bioremediation process. The dynamic change of microbial communities and metabolic genes in vertical depth soil from 0 to 80 cm were characterized to evaluate the petroleum degradation potential of indigenous microorganism. The influence of environmental variables on the microbial responds to petroleum contamination were analyzed. Degradation extent of 42.45% of n-alkanes(C8–C40) and 34.61% of 16ΣPAH were reached after 22 weeks. Relative abundance of alkB, nah, and phe gene showed about 10-fold increment in different depth of soil layers. Result of HTS profiles demonstrated that Pseudomonas, Marinobacter and Lactococcus were the major petroleum-degrading bacteria in0–30 and 30–60 cm depth of soils. Fusarium and Aspergillus were the dominant oil-degrading fungi in the 0–60 cm depth of soils. In 60–80 cm deep soil, anaerobic bacteria such as Bacteroidetes, Lactococcus, and Alcanivorax played important roles in petroleum *** analysis(RDA) and correlation analysis demonstrated that petroleum hydrocarbons(PHs) as well as soil salinity, clay content, and anaerobic conditions were the dominant effect factors on microbial community compositions in 0–30, 30–60, and 60–80 cm depth of soils, respectively.

关键词： Column microcosm Molecular analyses Petroleum hydrocarbons Microbial community Catabolic genes Saline alkaline soil

Development of a homogenous assay based on fluorescent imprinted nanoparticles for analysis of nitroaromatic compounds

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Nano Research 2019年第12期12卷 3044-3050页

作者： Asma Elbelazi Francesco Canfarotta joanna Czulak Michael j.Whitcombe Sergey Piletsky Elena Piletska Chemistry Department University of LeicesterLEI 7RHLeicesterUK Chemistry Department University of TripoliTripoliLibya MIP Diagnostics Ltd. Colworth Science ParkShambrookBedfordMK441LQUK

Herein we describe the development of a homogeneous assay for the detection of 4-nitroaniline(4-NA)and 2,4-dinitroaniline(2,4-diNA).Thisassay relies on fluorescent molecularly imprinted nanoparticles(nano MIPs)which,upon interaction with the target analytes,generate areduction in fluorescence emission intensity(quenching).This is due to a resp on sive fluorescent monomer(N-2-propenyl-(5-dimethylamino)-1-naphthalene sulphonamide)employed in the manufacture of the nanoMIPs which,by virtue of the imprinting process,is capable of selectiveinteraction with the target an alyte,thus giving rise to a quenching *** experiments showed excellent recognition propertiestoward the target *** optimal conditions,the fluorescence intensity of these nano MIPs decreased as the concentration of theimprinted analyte increased from 10 nM to 2.71 pM.A linear relation between the negative logarithm of 4-NA or 2,4-diNA concentrations and the fluorescence intensity for both nanosystems was found(R^2=0.991 and R^2=0.9895),with excellent sensitivity(limit of detection(LOD)=7 and 6 nM,respectively).Furthermore,both nanosystems have been successfully applied for detection of 4-NA or 2,4-diNA in tap water,withrecoveries between 90%to 100.6%and 92%to 100.3%,*** to the versatility of the imprinting process,this nanosystemholds the potential for further development of several optical sensors for many other compounds.

关键词： molecularly imprinted polymers quenching homogeneous assay nitroaromatic compounds

Seismic health monitoring of RC frame structures using smart aggregates

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 25-32页

作者： Wen-I Liao C.H.Lin j.S.Hwang G.Song Department of Civil Engineering Taipei University of Techology (NTUT) Department of Construction Engineering Taiwan University of Science and Technology Department of Mechanical Engineering University of Houston

Structural health monitoring of RC structures under seismic loads has recently attracted much attention in the earthquake engineering research community. In this study, a piezoceramic-based device called ＂smart aggregate＂ was used for the health monitoring of RC frame structures under earthquake excitations. Three RC moment frames instrumented with smart aggregates were tested using a shaketable with different ground excitation intensities. Distributed piezoceramic- based smart aggregates were embedded in the RC structures and used to monitor their health condition during the tests. The sensitivity and effectiveness of the proposed piezoceramic-based approach were investigated and evaluated by analyzing the measured responses. The displacement ductility demand of the structural members was calculated and compared with the damage index determined from the health monitoring system. The comparison shows that the damage index is compatible with the calculated ductility demand.

关键词： smart aggregate health monitoring RC frame shaketable piezoceramic

Sol–gel La2O3–ZrO2 mixed oxide catalysts for biodiesel production

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journal of Energy Chemistry 2018年第2期27卷 565-572页

作者： Daniela Salinas Catherine Sepúlveda Néstor Escalona j.L.GFierro Gina Pecchi Departamento de Fisicoquimica. Facultad de Ciencias Quimicas Universidad de Concepcion Post Office 160-C Concepcion Chile Departamento de Quimica Facultad de Ciencias Universidad del Biobio Post Office 5-C Concepcion Chile Departamento Ingenieria Quimica y Bioprocesos Escuela de lngenieria Pontificia Universidad Catolica de Chile Avda. Vicuria Mackenna 4870 Maeul Santiago 7820436 Chile Centro de Investigacion en Nanotecnolagia y Materiales Avanzados (CIEN-UC) Pontificia Universidad Catolica de Chile Post Office 306 Santiago Chile Departamento de Quimica Fisica Facultad de Quimica Pontificia Universidad Catolica de Chile Post Offce 306 Santiago Chile Instituto de Catalisis y Petroleoquimica CSIC 28049 Madrid. Espana

Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel *** biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.

关键词： La2O3 -ZrO2 Sol-gel Biodiesel Canola oil Transesterification