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Structural, elastic and electronic properties for M_2 Xc (M=Ti and cr, X=Ga and Al) phases from ab initio calculations

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Acta Metallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli M.A. Ghebouli M. Fatmi n. Bouarissa M. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids Materials Department of Physics Faculty of Science University of Setif Department of Physics University Center Research Unit on Emerging Materials Ferhat Abbas University of Setif Department of Physics Faculty of Sciences King Khalid University central Metallurgical Research and Development Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the M2Xc phases depending on the type of M transition metal （M are Ti and cr） and on X （X are Ga and A1） was reported. The calculations are performed using the pseudo-potential plane-wave approach in both the local density and generalized gradient approximations. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic parameters, Debye tem- perature, sound velocities and their pressure dependence have been investigated. In agreement with experimental and previous theoretical findings, it is found that the compressibility along a and c axis depends on the valence electron concentration （VEc）. correlations revealing the governing role of the X and M elements on the machinability indices of the material have been examined. The electronic properties have been discussed in terms of chemical bonding showing that bonding is due to Md-cp and Md-Xp hybridizations. M-c bonds are stiffer than M-X ones and A1-Ti （cr-c） bonds are stiffer than those corresponding to Ti-c （A1-cr）. It is shown that the stiffness of the M-X and M-c bonds increases with increasing the number of VEc.

关键词： M2Xc phases ab initio Pressure effect Band structures

Impact of introducing a herb pasture area into a new Zealand sheep and beef hill country farm system: a modeling analysis

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Frontiers of Agricultural Science and Engineering 2018年第1期5卷 87-97页

作者： cécile DURAnTOn cory MATTHEW Institute of Agriculture and Environment Massey University

new Zealand is well known for export of meat and dairy products from low cost pastoral systems. These farm systems are continually evolving for increased efficiency, in part through the use of metabolic energy modeling tools by farmers and farm consultants to explore alternative farm system configurations and identify new efficiencies. One recent innovation is the introduction of a herb pasture area, such as plantain. We used metabolic energy modeling to quantify seasonal feed flows in two successive years in a new Zealand hill country farm system, and to analyze the impact of the introduction of an area of plantain. Models employed were a self-built Microsoft Excel spreadsheet and a commercial new Zealand farm systems modeling package, *** production, animal performance and financial results for a base farm scenario created from the average of survey data for hill farms in the southern north Island, and the same farm with 10% and 20% of the area in plantain for the years 2010–2011 and 2011–2012 were modeled. The self-built model performed similarly to the commercial model. The system configuration of the base farm stockpiles surplus autumn feed for release to animals in winter and also incorporates flexibility that confers resilience to interannual weather variation through varying dates animals are purchased or sold. The introduction of an area of plantain was predicted to increase herbage production, animal performance and financial *** predicted benefit was higher for the year 2010–2011 where a drought occurred in summer than for the following year with higher summer rainfall. This demonstrates the profitability of introducing a plantain area to new Zealand hill farm systems, and suggests plantain will assist to mitigate adverse effects of warmer and drier summer conditions associated with current climate change trends.

关键词： farm system configuration herb pasture metabolic energy budgeting plantain sheep and beef farming

Observation of dipolar transport in one-dimensional photonic lattices

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Science Bulletin 2017年第5期62卷 339-344页

作者： camilo cantillano Luis Morales-Inostroza Bastián Real Santiago Rojas-Rojas Aldo Delgado Alexander Szameit Rodrigo A.Vicencio Departamento de Física MSI-Nucleus on Advanced Opticsand Center for Optics and Photonics(CEFOP)Facultad de CienciasUniversidad de ChileSantiagoChile center for Optics and Photonics and MSI-nucleus on Advanced Optics Universidad de ConcepciónCasilla 160-C ConcepcionChile Institute for Physics University of RostockD-18059 RostockGermany

We experimentally study the transport properties of dipolar and fundamental modes on one dimensional(1D) coupled waveguide arrays. By carefully modulating a wide optical beam, we are able to effectively excite dipolar or fundamental modes to study discrete diffraction(single-site excitation) and gaussian beam propagation(multi-site excitation plus a phase gradient). We observe that dipolar modes experience a larger spreading area due to an effective larger coupling constant, which is found to be more than two times larger than the one for fundamental modes. Additionally, we study the effect of non-diagonal disorder and find that while fundamental modes are already trapped on a weakly disorder array, dipoles are still able to propagate across the system.

关键词： Photonic lattices Waveguide arrays Wave propagation Integrated optics

Deep brain stimulation in Parkinson’s disease

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Translational neurodegeneration 2013年第1期2卷 154-163页

作者： Raja Mehanna Eugene c Lai UT Move University of Texas Health Care Science CenterHoustonTXUSA Department of neurology Houston Methodist Neurological Institute6560 FanninSuite 802Houston 77030TXUSA

For the last 50 years,levodopa has been the cornerstone of Parkinson’s disease ***,a majority of patients develop motor complications a few years after therapy *** brain stimulation has been approved by the FDA as an adjunctive treatment in Parkinson disease,especially aimed at controlling these ***,the exact mechanism of action of deep brain stimulation,the best nucleus to target as well as the best timing for surgery are still *** here provide an in-depth and critical review of the current literature on this topic.

关键词： Deep brain stimulation Parkinson’s disease Subthalamic nucleus Globus pallidus

Biogenesis of antibacterial silver nanoparticles using the endophytic bacterium Bacillus cereus isolated from Garcinia xanthochymus

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Asian Pacific Journal of Tropical Biomedicine 2012年第12期2卷 953-959页

作者： Swetha Sunkar c Valli nachiyar Department of Biotechnology Sathyabama University

Objective:To synthesize the ecofriendly nanoparticles,which is viewed as an alternative to the chemical method which initiated the use of microbes like bacteria and fungi in their ***:The current study uses the endophytic bacterium Bacillus cereus isolated from the Garcinia xanthochymus to synthesize the silver nanoparticles(AgnPs).The AgnPs were synthesized by reduction of silver nitrate solution by the endophytic bacterium after incubation for 3-5 d at room *** synthesis was initially observed by colour change from pale white to brown which was confirmed by UV-Vis *** AgnPs were further characterized using FTIR,SEM-EDX and TEM ***:The synthesized nanoparticles were found to he spherical with the size in the range of 20-40 nm which showed a slight *** energy-dispersive spectra of the nanoparticle dispersion confirmed the presence of elemental *** AgnPs were found to have antibacterial activity against a few pathogenic bacteria like Escherichia coli,Pseudomonas aeruginosa,Staphylococcus aureus,Salmonella typhi and Klebsiella ***:The endophytic bacteria identified as Bacillus cereus was able to synthesize silver nanoparticles with potential antibacterial activity.

关键词： Endophytic bacteria Bacillus cereus Silver nanoparticles UV-Vis spectra SEM TEM Antibacterial activity

Forensic interrogation of diabetic endothelitis in cardiovascular diseases and clinical translation in heart failure

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World Journal of cardiology 2020年第8期12卷 409-418页

作者： Merlin c Thomas Pupalan Iyngkaran Department of Diabetes Monash UniversityMelbourne 3004VictoriaAustralia Werribee Mercy Sub School School of Medicine SydneyUniversity of Notre DameNorthcote 3070VictoriaAustralia

Diabetic heart disease(DHD)can be classified as a primary consequence from several pathophysiological manifestation of diabetes mellitus(DM)on cardiac tissues or secondarily in extracardiac tissues and is encountered as either primary or secondary complications of *** is inflammation of the vascular endothelium and is likely to be seen in the majority of patients who start to manifest an end organ complication of DM in this case *** is a leading cause for many cardiovascular syndromes and diseases including congestive heart failure(cHF)however much remains unknown about the transition from diagnosed DM to clinical state and the contribution of the various mechanical and counterregulatory systems in the manifested *** heart failure or heart failure with preserved ejection fraction(DHF/HFpEF),accounts for half of all cHF presentations,has DM as a major contributor,however,there remain large gaps in clinical and pathophysiological *** review aims to explore the microscopic aspects in diabetic endothelitis and provide a clinical link to with context to HFpEF.

关键词： cardiovascular disease Diabetic heart disease Diabetes mellitus Diastolic heart failure Endothelitis Heart failure with preserved ejection fraction Inflammation

computational investigation of the effect of biodiesel fuel properties on diesel engine nOx emissions

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International Journal of Agricultural and Biological Engineering 2009年第2期2卷 41-48页

作者： Wenqiao Yuan A.c.Hansen Department of Biological and Agricultural Engineering Kansas State UniversityManhattanKS 66506USA Department of Agricultural and Biological Engineering University of IllinoisChampaignIL 61801USA

A detailed numerical spray atomization,ignition,combustion and nitrogen oxides(nOx)formation model was developed for direct injection diesel engines by using KIVA3V *** modified or recalibrated sub-models including a Kelvin-Helmholtz Rayleigh-Taylor(KH-RT)spray breakup model,a Shell ignition model,a single-step kinetic combustion model and a Zel’dovich nOx formation model were incorporated into *** modified model was validated by experimental data obtained from a John Deere 4045T direct injection diesel engine that was fueled with a natural soybean methyl ester,a yellow grease methyl ester,a genetically modified soybean methyl ester and no.2 diesel *** between predictions of the brake-specific nOx and measured values were less than 1%at full *** biodiesel fuels,either the Zel’dovich mechanism overpredicted nOx emissions,the ratio of nO to nOx should be less than diesel fuel,or *** observed from the modeling results,the higher latent heat of vaporization and higher surface tension of biodiesel relative to diesel fuel did not result in increased nOx *** higher viscosity of biodiesel could be one of the reasons for increased nOx,but its effect was relatively small compared with the effect of decreased spray cone angle and advanced start of injection timing on *** spray cone angle and advanced start of injection were the main reasons for increased nOx emissions of biodiesel.

关键词： biodiesel diesel engine modeling nOx emissions

A test method for evaluating the thermal environment of underground coal mine refuge alternatives

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International Journal of Mining Science and Technology 2019年第3期29卷 343-355页

作者： D.S.Yantek L.Yan n.W.Damiano M.A.Reyes J.R.Srednicki cDc nIOSH

Since 2009,the Mine Safety and Health Administration(MSHA)has required mines to install refuge alternatives(RAs)in underground coal *** of the biggest concerns with occupied RAs is the possible severity of the resulting thermal *** 30 cFR 7.504,the maximum allowable apparent temperature(AT)for an occupied RA is specified as 35℃(95°F).Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35℃(95°F)AT *** these tests,heat input devices are used to input the metabolic heat of actual miners.A wide variety of test methods,sensors,and heat input devices could be used when conducting such *** 2012,the national Institute for Occupational Safety and Health(nIOSH)has conducted over thirty 96-hour heat/humidity tests on four different *** paper discusses the test equipment and procedures used during these *** information is useful for RA manufacturers conducting RA heat/humidity tests,for other researchers investigating RA heat/humidity buildup,and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge.

关键词： Refuge chamber Refuge alternative confined space Thermal environment Test method Temperature

Three new records of cortinarius(cortinariaceae)for the Turkish Mycota from Trabzon,Turkey

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Studies in Fungi 2020年第1期5卷 517-525页

作者： Sesli E ÖrtücüS Trabzon University Fatih Faculty of EducationMathematics and Science EducationDepartment of BiologyTrabzonTurkey Erzurum Technical University High Technology Research and Application CentreErzurumTurkey

Basidiomata of cortinarius were collected during the field studies in 2019 and identified based on both morphological and molecular *** cortinarius species *** cadi-aguirrei,*** and *** are recorded for the first time... 详细信息

关键词： Agaricales Basidiomycota ITS identification taxonomy