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Journal of Advanced Ceramics 2019年第1期8卷 79-89页

作者： Bhupender RAWAL n. n. WATHORE B.prAVEEnKUMar H. S. PAnDA armament Research and Development Establishment Department of Materials Engineering Defence Institute of Advanced Technology

La_2 O_3 doped(na0.495 K0.455 Li0.05)(nb0.95 Ta0.05)O_3 ceramics are prepared using modified milling process, and the influences of La2 O3 on ferroelectric behaviour, ageing characteristics, thermal stability, electrical stability, crystal structure, microstructure, dielectric and piezoelectric properties were reported. La_2 O_3 addition improved the ferroelectric characteristic substantially, and obtained remnant polarization(pr) and maximum strain(Smax) around 34.3 C/cm^2 and 0.13% ***_2 O_3 doped ceramics improved the thermal stability and were stable up to 180 ℃ compared to undoped ceramics(120 ℃). The Rietveld refinement along with the high-temperature X-ray diffraction studies suggested the presence of monoclinic phase in La doped compositions, which is responsible for their idiosyncratic behaviour. The maximum values were obtained around 179 pC/n and 0.385 for piezoelectric constant(d33) and electromechanical coupling factor(kp) respectively in La_2 O_3 doped samples(0.02 wt%), which also exhibited the lowest ageing rate and stable electrical fatigue behaviour.

关键词： dielectric fatigue piezoelectric thermal stability

Denitrification from nitrogen-fixing biologically crusted soils in a cool desert environment,southeast Utah,USA

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Ecological processes 2013年第1期2卷 156-164页

作者： nichole n Barger Sarah C Castle Gavin n Dean Department of Ecology and Evolutionary Biology University of ColoradoCampus Box 334BoulderCO 80309-0334USA Department of Ecosystem and Conservation Sciences College of Forestry and ConservationUniversity of MontanaMissoulaMT59812USA.

Introduction:nitrogen fixation by microorganisms within biological soil crust(“biocrust”)communities provides an important pathway for n inputs in cool desert environments where soil nutrients are low and symbiotic n-fixing plants may be *** of n fixation in biocrusts often greatly exceed that of n accretion rates leading to uncertainty regarding n loss ***:In this study we examined nitrogen fixation and denitrification rates in biocrust communities that differed in n fixation potential(low n fixation=light cyanobacterial biocrust,high n fixation=dark cyanolichen crust)at four temperature levels(10,20,30,40°C)and four simulated rainfall levels(0.05,0.2,0.6,1 cm rain events)under controlled laboratory ***:Acetylene reduction rates(ar,an index of n fixation activity)were over six-fold higher in dark crusts relative to light *** biocrusts also exhibited eight-fold higher denitrification *** was no consistent effect of temperature on denitrification rates,but there was an interactive effect of water addition and crust *** light crusts,denitrification rates increased with increasing water addition,whereas the highest denitrification rates in dark crusts were observed at the lowest level of water ***:These results suggest that there are no clear and consistent environmental controls on short-term denitrification rates in these biologically crusted *** together,estimates of denitrification from light and dark biocrusts constituted 3 and 4%of n fixation rates,respectively suggesting that losses as denitrification are not significant relative to n inputs via *** estimate is based on a previously published conversion ratio of ethylene produced to n fixed that is low(0.295),resulting in high estimates of n *** future n fixation studies in biologically crusted soils show that these ratios are closer to the theoretical 3:1 ratio,denitrification may constitute a more significant

关键词： Biological soil crust Colorado Plateau Cool desert Denitrification nitrogen fixation Soil nitrogen cycling

On the Maximal Operator Associated with Certain Rotational Invariant Measures

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Acta Mathematica Sinica,English Series 2010年第6期26卷 993-1004页

作者： Adrián InFAnTE Fernando SORIA Department of Mathematics Universidad Simn Bolívar Department of Mathematics Universidad Autnoma de Madrid

The aim of this work is to investigate the integrability properties of the maximal operator Mu,associated with a non-doubling measure μ defined on Rn. We start by establishing for a wide class of radial and increasing measures μ that Mu is bounded on all the spaces Lu^p（R^n）,P〉***,we show that there is a radial and increasing measure p for which Mμ does not map Lμ^p（R^n） into weak Lμ^p（R^n）,1≤p〈∞.

关键词： maximal operator non-doubling measures

Effect of the Mineralogical Composition of Limestone on the properties of Mortars

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Journal of Materials Science and Chemical Engineering 2016年第5期4卷 16-24页

作者： Carla Macie arão Manhique Rodrigues Manjate Carvalho Madivate Laboratório de Engenharia de Mo?ambique Maputo Mo?ambique Departamento de Química da Universidade Eduardo Mondlane Maputo Mozambique

Limestone has been used as a partial substitute for cement, due to its beneficial effect on mechanical properties of mortars and concretes. In the present research, we studied the effect of the mineralogical composition in mortars produced from limestone samples collected in different areas of Mozambique, using two cement types (Portland cement 32.5n and 42.5n). Additions of 10 to 25% limestone gave, in general and for the 32.5n cement, good results of the compressive strength for all limestone samples, while for the 42.5n only the Massinga samples performed well. Effect of the limestone additions on the flexural strength showed a beneficial effect for all samples and at all compositions studied, when using the 42.5n cement, while for the 32.5n cement only additions of 10% limestone gave values of the flexural strength higher than the reference material, with the exception of the Magude samples.

关键词： Mortars Concrete Limestone Filler

Almond population genomics and non-additive GWAS reveal new insights into almond dissemination history and candidate genes for nut traits and blooming time

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Horticulture Research 2023年第10期10卷 262-272页

作者： Felipe Pérez de los Cobos Eva Coindre naima Dlalah Bénédicte Quilot-Turion Ignasi Batlle Pere arús Iban Eduardo Henri Duval Fruticultura Institut de Recerca i Tecnologia Agroalimentàries(IRTA)Mas BovéCtra.Reus-El Morell Km 3843120 ConstantíTarragonaSpain Centre de Recerca en Agrigenòmica(CRAG) CSIC-IRTA-UAB-UB.Institut de Recerca i Tecnologia Agroalimentàries(IRTA)Cerdanyola del Vallès(Bellaterra)08193 BarcelonaSpain Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB Campus UABEdifici CRAGCerdanyola del Vallès(Bellaterra)08193 BarcelonaSpain InRAE GAFLF-84143MontfavetFrance

Domestication drastically changed crop genomes,fixing alleles of interest and creating different genetic ***-wide association studies(GWASs)are a powerful tool to detect these alleles of interest(and so QTLs).In this study,we explored the genetic structure as well as additive and non-additive genotype-phenotype associations in a collection of 243 almond *** genetic structure analysis strongly supported the subdivision of the accessions into five ancestral groups,all formed by accessions with a common *** of these groups was formed exclusively by Spanish accessions,while the rest were mainly formed by accessions from China,Italy,France,and the *** results agree with archaeological and historical evidence that separate modern almond dissemination into four phases:Asiatic,Mediterranean,Californian,and southern *** total,we found 13 independent QTLs for nut weight,crack-out percentage,double kernels percentage,and blooming *** the 13 QTLs found,only one had an additive *** candidate gene analysis,we proposed prudul26A013473 as a candidate gene responsible for the main QTL found in crack-out percentage,prudul26A012082 and prudul26A017782 as candidate genes for the QTLs found in double kernels percentage,and prudul26A000954 as a candidate gene for the QTL found in blooming *** study enhances our knowledge of almond dissemination history and will have a great impact on almond breeding.

关键词： additive GWAS traits

Diallyl sulfide protects against n-nitrosodiethylamine-induced liver tumorigenesis:Role of aldose reductase

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World Journal of Gastroenterology 2008年第40期14卷 6145-6153页

作者： Safinaz S Ibrahim noha n nassar Department of Biochemistry Faculty of PharmacyCairo University Department of Pharmacology and Toxicology Faculty of PharmacyCairo University

AIM: To evaluate the protective effect of diallyl sulfide (DAS) against n-nitrosodiethylamine (nDEA)-induced liver ***: Male Wistar rats received either nDEA or nDEA together with DAS as *** energy metabolism was assessed in terms of lactate,pyruvate,lactate/pyruvate,ATP levels,lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G6PD) *** addition,membrane disintegration of the liver cells was evaluated by measuring lipid-peroxidation products,measured as malondialdehyde (MDA); nitric oxide (nO) levels; glucose-6-phosphatase (G6Pase),catalase (CAT) and superoxide dismutase (SOD) *** DnA level,glutathione-S-transferase (GST) and cytochrome c oxidase activities were used as DnA fragmentation *** reductase (ar) activity was measured as an index for cancer cells resistant to chemotherapy and histopathological examination was performed on liver sections from different ***: nDEA significantly disturbed liver functions and most of the aforementioned *** with DAS significantly restored liver functions and hepatocellular integrity; improved parameters of energy metabolism and suppressed free-radical ***: We provide evidence that DAS exerts a protective role on liver functions and tissue integrity in face of enhanced tumorigenesis caused by nDEA,as well as improving cancer-cell sensitivity to *** is mediated through combating oxidative stress of free radicals,improving the energy metabolic state of the cell,and enhancing the activity of G6Pase,GST and ar enzymes.

关键词： n-nitrosodiethylamine Diallyl sulfide Liver cancer Energy metabolism Aldose reductase

Investigations on luminescence of rare earths doped CaTiO_3:pr^(3+) phosphor

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Journal of Rare Earths 2010年第4期28卷 488-492页

作者： n. Suriyamurthy B.S. Panigrahi Radiological Safety Division Technical Services Division Indira Gandhi Centre for Atomic Research Kalpakkam-603 102 India

Calcium titanate doped with praseodymium was prepared through solid state reaction and it exhibited intense red emission at 612 nm. Phosphors were characterized for photoluminescence, thermo-luminescence and afterglow emissions. Study of effects of rare earths on photoluminescence as well as afterglow intensity was reported. presence of gadolinium enhanced luminescence. presence of some monovalent ions enhanced both afterglow and photoluminescence emission. Thermo-luminescence glow curves were analyzed and ...

关键词： perovskites calcium titanates red afterglow rare earths

Study of the dinuclear system for^(296)119 superheavy compound nucleus in fusion reactions

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Chinese Physics C 2021年第4期45卷 325-334页

作者： J.Mohammadi O.n.Ghodsi Department of Physics Faculty of ScienceUniversity of MazandaranP.O.Box 47415-416BabolsarIran

This investigation aims to find an appropriate dinuclear system for the formation of^(296)119 superheavy compound *** studying the driving potential and measuring the capture cross section of the reactions,the evolution of the dinuclear system can be *** this study,we obtained capture,fusion,and evaporation residue cross sections and survival probability at energies near the Coulomb barrier for four reactions,namely ^(45)Sc+^(251)Cf,^(42)Ca+^(254)Es,^(39)K+^(297)Fm,and ^(38)ar+^(258)*** caleulations show that the reaction 38ar+258 Md is a suitable choice for the formation of an element with 119 protons among the studied reactions from a the-oretical viewpoint.

关键词： dinuclear system cross section fusion reaction superheavy elements

Kinetic and Thermodynamic Study of arsenic (V) Adsorption on P and W Aluminum Functionalized Zeolites and Its Regeneration

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Journal of Water Resource and protection 2013年第8期5卷 58-67页

作者： Adriana Medina Ramírez prócoro Gamero Melo José Manuel Almanza Robles María Esther Sánchez Castro Sasirot Khamkure Roberto García de León 1Sustainability of the natural Resources and Energy CINVESTAV Saltillo Ramos Arizpe Mexico 2Nanotechnology Engineering University of La Ciénega of the Michoacan State Sahuayo Mexico Sustainability of the natural Resources and Energy CINVESTAV Saltillo Ramos Arizpe Mexico Transformation processes Mexican Petroleum Institute Mexico City Mexico

In the “Laguna” region of Coahuila state, Mexico like other places in the world, the groundwater needs to be treated to meet the quality required for human consumption. The study had probed that a Mexican fly ash can be used as a raw material to obtain effective low cost adsorbents for drinking water treatment, as well evaluated the effects of pH, ion coexistence, dose, arsenic (As) concentration and temperature on the As(V) uptake by using P and W modified zeolites (PMOD and WMOD) obtained from a Mexican fly ash. The As(V) adsorption capacity of the WMOD zeolite was not affected by pH and As(V) concentrations in aqueous solution was achieved 0.01 mg/L in the studied pH range;however, the As(V) removal by using PMOD zeolite decreased at high pH values. Carbonate concentration had a negative effect on the As(V) uptake of both zeolites but this effect was higher for the PMOD zeolite. The maximum adsorption capacities (Qmax) were 76.11 and 44.44 mg of As(V)/g of zeolite for the WMOD and the PMOD zeolites, respectively. The adsorption process was endothermic, spontaneous and occurred by chemical exchange. The experimental data were best interpreted by a pseudo-second order kinetic model. The WMOD zeolite showed a higher adsorption capacity and rate than the PMOD even at the highest evaluated As(V) concentration. The adsorption capacity of the regenerated WMOD zeolite was similar to the original zeolite. Because of the high As(V) adsorption capacity, chemical stability and regenerability, the WMOD zeolite is potentially useful as low-cost adsorbent for As(V) removal from aqueous effluents.

关键词： Fly Ash Zeolite arsenic (V) Removal Adsorbent Regeneration

RecQ Helicase-catalyzed DnA Unwinding Detected by Fluorescence Resonance Energy Transfer

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Acta Biochimica et Biophysica Sinica 2005年第9期37卷 593-600页

作者： Xing-Dong ZHAnG Shuo-Xing DOU Ping XIE Peng-Ye WAnG Xu Guang XI Laboratory of Soft Matter Physics,Beijing national Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100080,China Laboratoire de Biotechnologies et Pharmacologie Génétique Appliquée CnRS UMR 8113.Ecole normale Supérieure de Cachan,61 Avenue du président Wilson,94235 Cachan cedex,France Laboratory of Soft Matter Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of SciencesBeijing 100080 China Laboratoire de Biotechnologies et Pharmacologie Génétique Appliquée CnRS UMR 8113 Ecole Normale Supérieure de Cachan61 Avenue du Président Wilson 94235 Cachan cedex France

A fluorometric assay was used to study the DnA unwinding kinetics induced by Escherichiacoli RecQ *** assay was based on fluorescence resonance energy transfer and carried out onstopped-flow,in which DnA unwinding was monitored by fluorescence emission enhancement of fluoresceinresulting from helicase-catalyzed DnA *** this method,we determined the DnA unwinding rateof RecQ at different enzyme *** also studied the dependences of DnA unwinding magnitudeand rate on magnesium ion *** showed that this method could be used to determine thepolarity of DnA *** assay should greatly facilitate further study of the mechanism for RecQ-catalyzed DnA unwinding.

关键词： helicase DnA unwinding kinetics stopped-flow fluorescence resonance energy transfer (FRET)