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Ti-doped nano-porous graphene： A material for hydrogen storage and sensor

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Frontiers of physics 2011年第2期6卷 204-208页

作者： sa LI Hong-min ZHAO Puru JENA Department of Physics Virginia Commonwealth University Richmond VA 23284 USA Department of Physics School of Science Beijing Jiaotong University Beijing 100044 China

Clustering of Ti on carbon nanostructures has proved to be an obstacle in their use as hydrogen storage materials. Using density functional theory we show that Ti atoms will not cluster at moderate concentrations when doped into nanoporous graphene. Since each Ti atom can bind up to three hydrogen molecules with an average binding energy of 0.54 eV/H2, this material can be ideal for storing hydrogen under ambient thermodynamic conditions. In addition, nanoporous graphene is magnetic with or without Ti doping, but when it is fully saturated with hydrogen, the magnetism disappears. This novel feature suggests that nanoporous graphene cannot only be used for storing hydrogen, but also as a hydrogen sensor.

关键词： nano-porous graphene hydrogen storage hydrogen sensor

Halophily reloaded:new insights into the extremophilic life-style of Wallemia with the description of Wallemia hederae ***

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Fungal Diversity 2016年第1期76卷 97-118页

作者： sašo Jančič Polona Zalar Dragi Kocev Hans-Josef Schroers sašo Džeroski Nina Gunde-Cimerman Department of Biology Biotechnical FacultyJamnikarjeva 101SI-1000 LjubljanaSlovenia Department of Knowledge Technologies Jožef Stefan InstituteJamova cesta 39SI-1000 LjubljanaSlovenia Agricultural Institute of Slovenia Hacquetova 17p.p.2553SI-1000 LjubljanaSlovenia Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins(CIPKeBiP) Jamova cesta 39SI-1000 LjubljanaSlovenia

Wallemia comprises air-and food-borne,mycotoxigenic contaminants including the halophilic ***,xerotolerant *** and xerophilic *** isolates are easily overlooked and only a comparably small number of strains have been deposited in culture collections so *** order to better understand the natural distribution of Wallemia *** to encounter their natural habitats,we tested more than 300 low-water-activity substrates and 30 air samples from a wide geographical *** isolated more than 150 new Wallemia *** sebi and *** were isolated mostly from hypersaline water,low-water-activity foods,plant materials and *** muriae is the dominant Wallemia species in the air of natural and human influenced environments in *** isolates of *** were obtained from hypersaline environments such as brine,salt crystals,salty foods and MgCl_(2)-rich bitterns,and from the air of hay barns in *** halotolerant strains were recognised as a hitherto un-described species Wallemia hederae,the phylogenetic sister of the halophilic *** *** in-vitro growth on media that contain the chaotropic salt MgCl_(2).Wallemia ichthyophaga can grow in liquid medium enriched with 2 M MgCl_(2).Never before has a microorganism been grown on comparably high MgCl_(2) *** of the activity of a wide range of extracellular enzymes in the presence of NaCl also suggested that Wallemia iswell-adapted to substrates with a reduced water activity.

关键词： Chaophiles Ecophysiology Extracellular enzymes Exudates Machine learning Taxonomy

edge Detectors Based on Pauta Criterion with Application to Hybrid Compact-WENO Finite Difference Scheme

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Advances in Applied Mathematics and Mechanics 2023年第6期15卷 1379-1406页

作者： Chunhua Zhang Zhen Gao sa Ye Peng Li School of Mathematical Sciences Ocean University of ChinaQingdaoShandong 266100China Institute of Agricultural Information Chinese Academy of Agricultural SciencesKey Laboratory of Agricultural Big DataMinistry of Agriculture and Rural AffairsBeijing 100081China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuangHebei 050043China

In the last two decades,many edge detection methods have been developed and widely used in image processing for edge detection and the hybrid compactWENO finite difference(hybrid)schemes for solving the system of hyperbolic conservation laws with solutions containing both discontinuous and complex fine-scale ***,many edge detection methods include the problem-dependent parameters such as the high order multi-resolution(MR)analysis(Harten,JCP,49(1983)).Therefore,we combined the Tukey’s boxplot method with MR analysis(Gao et al.,JSC,73(2017))to overcome this problem in a *** the Tukey’s boxplot method needs to sort the data at the beginning of Runge-Kutta time integration method,which is relatively time-consuming and *** this study,we employ the PauTa criterion and remove the problem-dependent parameters in the MR ***,two new edge detection approaches,which are based on second-order central difference scheme and Ren’s idea(Ren et al.,JCP,192(2003)),are also *** accuracy,efficiency and robustness of the hybrid scheme with the new edge detectors are verified by numerous classical one-and two-dimensional examples in the image processing and compressible Euler equations with discontinuous solutions.

关键词： edge detection Pauta criterion multi-resolution hybrid

Collisionless tool orientation smoothing above blade stream surface using NURBS envelope

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第3期14卷 187-197页

作者： Jing-hua XU Shu-you ZHANG Jian-rong TAN Ri-na sa State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

In five-axis machining,tool orientation above a blade stream surface may lead to tool collision and a decrease in workpiece ***,collisionless tool orientation smoothing(TOS)becomes an important *** the basis of a constant scallop height tool path,the triangular facets in the faces,vertices format are constructed from cutter contact(CC)using the Voronoi incremental *** cutter location(CL)points candidate set is represented by an oblique elliptic cone whose vertex lies at CC using NURBS *** the CL point is above its CC is judged by the dot product between the normal vector and the point on triangulation nearest to the CL *** curvatures at CC are obtained by fitting a moving least square(MLS) quadratic patch to the local neighborhood of a vertex and calculating eigenvectors and eigenvalues of the Hessian *** surface elastic energy is employed as the weight in selection from the NURBS *** collision is judged by NURBS surface *** can then be expressed by selecting a CL point for each CC point and converted into a numerical control(NC)code automatically according to the postprocessor type of the machine *** proposed method is verified by finishing of a cryogenic turboexpander impeller of air separation equipment.

关键词： Tool orientation smoothing(TOS) Blade stream surface Triangular facet NURBS envelope Surface elastic energy

Soundscape Dynamics at Anuran Reproductive Sites in Pannonian Biogeographical Region：Effects of Road Noise on Vocal Activity

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Asian Herpetological Research 2016年第1期7卷 34-40页

作者： András WEIPERTH ed SMITH Szilvia SIMIGLA Miklòs PUKY Yezhong TANG MTA Centre Jor Ecological Research Danube Research Institute H- 1113 Budapest Karolina ut 29 Hungary Department of Psychology University of Maryland College Park MD 20742 USA Chengdu Institute of Biology Chinese Academy of Sciences # 9 of Section 4 South Renmin Road Chengdu 610041 Sichuan China

The emerging field of soundscape ecology views ecosystems in terms of biophony, geophony and anthrophony. Soundscape ecology considers the effects of sound on fauna, and this research focuses on anuran breeding lek soundscapes. The sensitivity of anuran breeding leks to acoustic disturbances makes breeding leks an important venue for a comparative soundscape study. We made long-term（〉 24 h） sound recordings in three representative wetlands and short-term（〈 30 min） recordings in ten sites in the Pannonian Biogeographical Region of Hungary and around the Hungary and Slovakia border. Long-term soundscapes of the floodplain stretch, where there is relatively minor anthrophonical disturbance, showed an obvious circadian change in sound intensities. The site with moderate sound contamination exhibited a disturbed pattern of circadian sound variation, while the site with heavy traffic noise displayed an apparently random temporal soundscape. At different amphibian breeding sites during mating season, our short-term recordings were dominated by anuran calls, bird songs and wind noises, while insect calls and rain were present to a lesser degree. Our study indicates that vehicle traffic noise is a severe imposition to the natural soundscape, and suggests that soundscape monitoring can provide a reliable and sensitive index of environmental change for both short-term and long-term periods.

关键词： soundscape monitoring anuran breeding site biophony geophony anthrophony

Socio-economic importance and utilization of Spondias mombin in Nigeria

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Asian Pacific Journal of Tropical Medicine 2010年第3期3卷 232-234页

作者： Adedokun MO Oladoye AO Oluwalana sa Mendie Ⅱ Department of Forestry & Wildlife Management College of Environmental ManagementUniversity of Agriculture

Objective:To investigate the socio-economics and medicinal utilization of Spondia monbin, commonly known as plum in English and iyeye in ***:Three communities were selected in Abeokuta which was Itoku,Kuto,and Omida using purposive random sampling technique because of the concentration of users in the *** questionnaire was administered to randomly selected marketers,consumers and herbalists from the three *** and marketing margin were descriptively ***:The results showed that the leaves were being used for child birth aid,cough,sore throat,efu dudu,antiseptic soap,malaria and *** bark uses included child birth aid,inflammation concoction, fever,stomachic,malaria,and efu *** uses of the fruit included cure for dizziness, stomachic,eaten as food,and *** seed were also being used for child birth aid,fibroid, and *** marketing margin analyses revealed that trading on the plants was profitable with the bark having the highest margin which showed the level of its ***: The study reveals the medicinal potentials and the socioeconomic importance of Spondia mombin hence the need to conserve the species from unsustainable exploitation to ensure its availability.

关键词： Spondia mombin Trado-medical practitioners Market margin Medicinal uses Marketers

Paralog-divergent Features May Help Reduce Off-target Effects of Drugs:Hints from Glucagon Subfamily Analysis

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Genomics, Proteomics & Bioinformatics 2017年第4期15卷 246-254页

作者： Zhining sa Jingqi Zhou Yangyun Zou Zhixi Su Xun Gu State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology School of LifeSciencesFudan UniversityShanghai 200433China Department of Genetics Development and Cell BiologyProgram of Bioinformatics and Computational BiologyIowa State UniversityAmesIA 50011USA

Side effects from targeted drugs remain a serious conccrn. One reason is the nonselective binding of a drug to unintended proteins such as its paralogs, which arc highly homologous in sequences and have similar structures and drug-binding pockets. To identify targctablc differences between paralogs, we analyzed two types （type-I and type-ll） of functional divergence between two paralogs in the known target protein receptor family G-protein coupled receptors （GPCRs） at the amino acid level. Paralogous protein receptors in glucagon-like subfamily, glucagon receptor （GCGR） and glucagon-like peptide-I receptor （GLP-I R）, exhibit divergence in ligands and are clinically validated drug targets for type 2 diabetes. Our data showed that type-ll alnino acids were significantly enriched in the binding sites of antagonist MK-0893 to GCGR. which had a radical shift in physicochemical properties between GCGR and GLP-1R. We also examined the role of type-I amino acids between GCGR and GLP-ir. The divergent features between GCGR and GLP-I R paralogs may be helpful in their discrimination, thus enabling the identification of binding sites to reduce undesirable side effects and increase the target specificity of drugs.

关键词： Paralog Functional divergence Functional site Drug specificity Evolutionary conservation

Density Effects on Plant Height Growth and Inequality in Sunflower Populations

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作者： ed McDonald.

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Journal of Integrative Plant Biology 2006年第5期48卷 513-519页

作者： sa Xiao Shu-Yan Chen Lu-Qiang Zhao Gang Wang Laboratory of Arid Agroecology School of Life Sciences Lanzhou University Lanzhou 73000 China

Comparisons between competing and non-competing sunflower （Helianthus annuus L.） populations demonstrate pronounced effects of density on plant height growth, height-to-crown width ratio, and s popuiaUon＇s height inequality. In the present study, non-destructive measurements of height and the prolected crown area of sunflower plants were taken at seven times from emergence to fruit maturation in even-aged monospeclflc stands with initial densities of 1, 4, 16, and 64 plants/m^2. The mean height of populations Increased and then decreased with increasing population density; the height Inequalities of uncrowded populations decreased during stand growth, whereas the height inequaiiUes of crowded popuisUons decreased first and then increased during stand development. The interindlvidual relationships between the relative height growth rate and height within uncrowded populations became significantly negative during population growth, whereas these relationships were negative first and then became positive during the development of crowded populations. In the uncrowded populations, the static Interindlvldual relationship between height-to-crown width ratio and volume was positive, whereas for the crowded population these relationships became negative with increasing competition for light. The data suggest that the plastic responses of plant height and height-to-crown width ratio to light competition will become more Intense with increasing competition Intensity. The results of the present study argue strongly for the Importance of size-dependent Individual-level plastic responses due to size-asymmetric light competition In generating the variations in population height inequality.

关键词： height inequality light competition plasticity size dependent.