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Energy Gap and Electron Effective Mass in Chlorine Halide Superconductor at High Pressure

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Chinese Physics Letters 2014年第11期31卷 140-143页

作者： r. Szczesiak d. Szczesiak Institute of Physics Czestochowa University of Technology A1. Armii Krajowej 19 Czestochowa 42-200 Poland Institute of Physics Jan Dtugosz University in Czestochowa AI. Armii Krajowej 13/15 Czestochowa 42-200 Poland

dependences of the order parameter （ A ） and the electron effective mass （me^＊） on the temperature for the chlorine halide superconductor are determined in the present work. The high values of the pressure （p1 = 320 GPa andp2 = 360 GPa）, for which the critical temperature is equal to [Tc]m = 30.6 K and [Tc]p2 = 41.5 K, are taken into consideration. It is found that the dependence of the order parameter on the temperature deviates from the predictions of the classical Bardeen-Cooper-Schrieffer theory, due to the existence of the significant strong- coupling and retardation effects. The values of the order parameter, for the temperature close to zero Kelvin, are equal to [A（0）]p1 = 4.89 meV and [A（0）]p2 = 6.82 meV. The obtained results allowed next to calculate the dimensionless ratio r△ = 2A（O）/kBTc, which is equal to 3.71 and 3.81 in respect to pl and p2. In the last step, it is proven that the electron effective mass is weakly dependent on the temperature in the area of the existence of the superconducting state and reaches its maximum at the critical temperature. For the considered values of the max ＊ max pressure, we obtain [me^＊]pl^max = 1.69me and [me^＊]p2^max =1.78me, where the symbol me denotes the electron band mass.

关键词： ENErGY gaps (Physics) CHLOrINE halides SUPErCONdUCTOrS BCS theory (Superconductivity) EFFECTIVE mass (Physics)

Novel acid initiators for the rapid cationic polymerization of styrene in room temperature ionic liquids

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Science China Chemistry 2012年第8期55卷 1671-1676页

作者： VIJAYArAGHAVAN r. MACFArLANE d. r. department of Chemistry Monash University Clayton Campus Victoria 3800 Australia

Cationic polymerization of styrene has been achieved using several novel acidic initiators in room temperature ionic liquids (ILs) under mild reaction conditions to obtain polymers of low molecular weight with narrow polydispersity. Both strong protic acids such as bis(trifluoromethanesulfonyl) amide acid (HTFSA) and a moderately weak acid such as bisoxalato phosphorous acid (HBOP) have been studied as initiators. It has been observed that HTFSA initiates the polymerization rapidly even at room temperature and below, as compared to HBOP which produces a slower polymerization requiring elevated temperatures to complete. The relative difference in reactivity of the initiators as compared to the previously described HBOB initiator is discussed in terms of the difference in their proton acidity and the consequential basicity of the anions. The efficiency of different ILs as the reaction solvent is also presented.

关键词： cationic polymerization HTFSA HBOP ILs polydispersity

Induction of osteoblast differentiation in human adipose derived stem cells by lanthanum ions

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Journal of rare Earths 2014年第11期32卷 1080-1088页

作者： Harini d Indra r rajaram A rama rajaram department of Biochemistry Central Leather Research Institute department of Biophysics Central Leather Research Institute

Adipose derived stem cells represent a readily available source of adult stem cells for various biomedical applications. In this study, the proliferation and osteogenic differentiation potential of lanthanum nitrate（La3＋） on human adipose derived mesenchymal stem cells（hAdSCs） were investigated for the first time and compared with that of dexamethasone（dex）. Our results provided evidence that La3＋ at 50 μmol/L concentration promoted proliferation of hAdSCs upto 2.4 fold when treated for 21 d in dMEM medium. Treatment of hAdSCs with La3＋ containing osteogenic induction medium（α-MEM with ascorbic acid and β-glycerophosphate） for 7 d resulted in higher calcium deposition than that in the presence of dex（0.1 μmol/L） as shown by Alizarin red S and von Kossa staining. Scanning electron micrographs also showed more extracellular matrix mineralization in the presence of La3＋. After 7 d of treatment with La3＋（10 μmol/L） the expression of runX2, osteopontin（OP） and osteocalcin（OC） increased 3.4, 5.5 and 2.7 fold respectively. Our results provided evidence that in the presence of La3＋ osteogenic differentiation occurred earlier than that in the presence of dex.

关键词： hAdSCs lanthanum osteoblast differentiation genes calcium deposition SEM runX2 rare earths

Insight of magnesium alloys and composites for orthopedic implant applications-a review

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Journal of Magnesium and Alloys 2017年第3期5卷 286-312页

作者： r radha d Sreekanth School of Mechanical and Building Sciences VIT UniversityChennaiIndia

Magnesium(Mg)and its alloys have been widely researched for orthopedic applications *** alloys have stupendous advantages over the commercially available stainless steel,Co-Cr-Ni alloy and titanium *** date,extensive mechanical,in-vitro and in-vivo studies have been done to improve the biomedical performance of Mg alloys through alloying,processing conditions,surface modification *** review comprehensively describes the strategies for improving the mechanical and degradation performance of Mg alloys through properly tailoring the composition of alloying elements,reinforcements and processing *** also highlights the status and progress of research in to(i)the selection of nutrient elements for alloying,reinforcement and its effects(ii)type of Mg alloy system(binary,ternary and quaternary)and composites(iii)grain refinement for strengthening through severe plastic deformation *** it also emphasizes on the importance of Mg composites with regard to hard tissue applications.

关键词： Orthopedic implants Magnesium Alloy system Composites Grain refinement Processing,degradation,strengthening

Effects of symmetric and asymmetric salt conditions on a selective solid-state nanopore assay

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Nano research 2022年第11期15卷 9936-9942页

作者： Ian d.Wadsworth Adam r.Hall Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences Wake Forest School of MedicineWinston-SalemNC 27101USA Comprehensive Cancer Center Wake Forest School of MedicineWinston-SalemNC 27157USA

Conventional solid-state nanopore measurements sense all translocating entities,necessitating meticulous analysis to differentiate target *** address this,we have established a selective assay with the platform that has shown utility in quantifying several nucleic acid ***,limited detection efficiency and intrinsic noise have so far limited assay resolution to 10 *** in this value require manipulation of translocation ***,we report the effects of NaCl conditions on assay *** first investigate symmetric conditions,finding sensitivity increases with salt concentration but selectivity is maximized at 1.0 M *** then probe asymmetric conditions,showing a remarkable impact on assay sensitivity and selectivity when measurement buffer NaCl concentration in the reservoir with the translocating molecules is low and the opposite reservoir is *** optimum conditions,we demonstrate detection of target biomolecules down to a concentration of 100 pM which is an improvement of 2 orders of magnitude over past results.

关键词： solid-state nanopores biomarkers amplification-free detection salt gradient nucleic acids

Lattice thermal conduction in cadmium arsenide

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Chinese Physics B 2022年第11期31卷 424-430页

作者： r F Chinnappagoudra M d Kamatagi N r Patil N S Sankeshwar department of Physics S.S.Government First Grade CollegeNargund-582207KarnatakaIndia research resource Centre Visvesvaraya Technological UniversityBelagavi-590018KarnatakIndia department of Physics B V B College of Engineering and TechnologyHubliKarnataka 80031India department of Physics&Electronics CHRIST(Deemed to be University)Bangalore-560029KarnatakaIndia

Lattice thermal conductivity(LTC)of cadmium arsenide(Cd_(3)As_(2))is studied over a wide temperature range(1–400 K)by employing the Callaway *** acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries,disorder,impurities,and other phonons via both Umklapp and normal phonon *** calculations of LTC of Cd_(3)As_(2)bring out the relative importance of the scattering *** systematic analysis of recent experimental data on thermal conductivity(TC)of Cd_(3)As_(2)samples of different groups,presented in terms of LTC,κL,using a nonlinear regression method,reveals good fits to the TC data of the samples considered for Td suggests a value of 0.2 for the Gruneisen *** is,however,found that for T>100 K the inclusion of the electronic component of TC,κe,incorporating contributions from relevant electron scattering mechanisms,is needed to obtain good agreement with the TC data over the wide temperature *** detailed investigations of TC of Cd_(3)As_(2)are required to better understand its suitability in thermoelectric and thermal management devices.

关键词： dirac semimetals Cd_(3)As_(2) thermal conductivity phonon scattering

region-Aware Trace Signal Selection Using Machine Learning Technique for Silicon Validation and debug

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Computer Modeling in Engineering & Sciences 2019年第7期120卷 25-43页

作者： r.Agalya r.Muthaiah d.Muralidharan Junior research Fellow School of ComputingSASTRA Deemed UniversityThirumalaisamudramThanjavur-613401TamilnaduIndia Associate dean School of ComputingSASTRA Deemed UniversityThirumalaisamudramThanjavur-613401TamilnaduIndia Assistant Professor School of ComputingSASTRA Deemed UniversityThirumalaisamudramThanjavur-613401TamilnaduIndia

In today’s modern design technology,post-silicon validation is an expensive and composite *** major challenge involved in this method is that it has limited observability and controllability of internal *** will be an issue during execution how to address the useful set of signals and store it in the on-chip trace *** existing approaches are restricted to particular debug set-up where all the components have equivalent prominence at all the ***,the verification engineers will emphasis only on useful functional regions or *** to some constraints like clock gating,some of the regions can be ignored during ***,some of these regions can be verified deeply and have minimum errors compared to other control *** proposed system focusses on random signals that identify more errors which are prone to signal selection technique with low area *** enhance the observability,a machine learning technique is *** on the training samples of smaller designs,a model is developed to find out the contiguous neighbours of each *** can eliminate the obstacles of unknown *** system demonstrates using Opencores and ISCAS’89 benchmark circuits that result in easy and fast error detection compared to the state-of-theart of other *** is also verified using gate-level error models by cross-validation of each debug run.

关键词： Controllability error propagation machine learning observability signal selection

Annual-perennial plant relationships and species selection for desert restoration

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Journal of Arid Land 2013年第3期5卷 298-309页

作者： Scott r ABELLA Stanley d SMITH department of Environmental and Occupational Health University of Nevada Las VegasLas VegasNevada 89154-3064USA School of Life Sciences University of Nevada Las VegasLas VegasNevada 89154-4004USA

Exotic plant invasion is a growing concern in the conservation and management of indigenous arid land ecosystems. By creating areas of ameliorated microclimates and fertile soil below their canopies, perennial plants might influence exotic annual plant invasions. We conducted a quantitative literature review of studies that compared exotic annual plant abundance among native perennial plant species and interspace （open areas） microsites in North America＇s Mojave desert, where exotic plant invasion has corresponded with increasing extent of wildfire and broad-scale ecosystem transformation. Ten studies compared exotic annual plant abundance between inter- spaces and below a total of 36 native perennial species. These studies revealed that：（1） With few exceptions, most native perennial species supported a greater abundance of exotic annuals than interspaces, indicating overall facilitation of exotic species by native perennials. （2） Exotic species abundance varied by orders of magnitude among native perennial species, with some perennial species harboring amounts of exotics similar to interspaces. （3） distributions of dominant exotic species varied, where Bromus rubens displayed a greater affinity for below-perennial microsites than did Schismus spp. and Erodium cicutarium that often were most abundant in interspaces. results suggest that the degree of facilitation of exotic plants warrants consideration when selecting native perennial species for revegetation and restoration projects.

关键词： Bromus rubens exotic fertile island invasive nurse plant positive plant interaction Schismus

A COMBINATOrIAL APPrOACH TO THE OXIdATION rESISTANCE OF (Ti,Al)N ANd Ti-Al-Si-N HArd COATINGS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 6-14页

作者： r. Cremer d. Neuschutz Lehrshl für Theoretische Hüttenkunde Rheinisch-Westfalische Technische Hochschule Aachen 52056 AachenGermany

The increasing complexity of modern functional materials leads to the demandof a cost efficient tool for the development of new products. One possible approach to this questionis the adaptation of combinatorial methods to the specific requirements of materials *** methods, originally developed for the pharmaceutical industry, have recently been applied tothe screening of superconductive, magnetoresistant and photoluminescent materials. The principle ofthese combinatorial approaches is the deposition of large materials libraries in one processcombined with fast methods for the determination of the resulting properties. In this paper, thedeposition and characterization of laterally graded materials libraries (composition spread) ispresented. The films have been deposited by reactive magnetron sputtering, using two or threemetallic targets at a low angle to the substrate surface as well as a system of apertures. Toillustrate the advantages of combinatorial approaches for the development of advanced materials, themulticomponent metastable hardcoatings (Ti,Al)N and Ti-Al-Si-N are discussed with special emphasison the relations between structure and composition on the one hand and the oxidation resistance ofthese coatings on the other. The results illustrate that the composition spread approach is apowerful and cost efficient tool for the development and optimization of new multicomponentfunctional materials.

关键词： combinatorial chemistry hard coating PVd magnetron sputtering