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Biomedical and Environmental Sciences 1994年第1期7卷 56-67页

作者： P.k.RAI NirupamaMALLICk 等 laboratoryofAlgalBiology CentreofAdvancedStudyinBotanyBanarasHinduUniversityVaransi－221005India la

A pH dependent reduction in growth, Pigment, ATP content, O,' evolution, carbonfixation, Photosynthetic electron transport system, nutrient uptake (NO,' and NH4+),nitrate reductase, and ATPase activities and increase in k+ emux of Chlorella vulgaris wasnoticed following supplementation of Cu and Ni to the culture medium. PS II was foundto be more sensitive to both pH and metals than PS I. Though, nitrate reductase (NR) wasmore sensitive to both PH and metals, the ATPase was however, more sensitive t0 metalsbut less sensitive to acidic pH. Acid PH was found to dst the nutrient (NO,' and NH4+)uptake and nitrate reductase in a non-competitive manner. The inhibition Pnduced by thetest metals alone was of noncompetitive type for NO3' uptake, nitrate reductase andATPase and competitive for NH'+ uptake. Acidity not only inhibited the metabolicvariables directly but also through facilitated uptake of metals and increased membranepermeability. A very low sensitivity of ATPase to acidic pH seems to be resgnsible forthe survival of algae in acid environment.

关键词： Mineral Uptake,Photosynthesis and Enzyme Activities of Chlorella vulgaris at Different pH Values Effect of Cu and Ni on Growth pH Cu Ni

Random crystal field effect on hysteresis loops and compensation behavior of mixed spin-(1,3/2) Ising system

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Chinese Physics B 2017年第12期26卷 538-547页

作者： k Htoutou Y Benhouria A Oubelkacem R Ahl laamara L B Drissi LPHE-Modeling and Simulations Faculty of Sciences Mohammed V University in Rabat Morocco Center Regional des Metiers de l'Education et de la Formation (CRMEF) Fes-Meknes Marocco LP2MS University of Moulay Ismail Faculty of Sciences Meknes Morocco Center of Physics and Mathematics CPM-Morocco

Magnetic hysteresis and compensation behavior of a mixed spin-（1, 3/2） Ising model on a square lattice are investigated in the framework of effective field theory based on a probability distribution technique. The effect of random crystal field, ferromagnetic and ferrimagnetic exchange interaction on hysteresis loops and compensation phenomenon are discussed. A number of characteristic phenomena have been reported such as the observation of triple hysteresis loops at low temperatures and for negative values of random crystal field. Critical and double compensation temperatures have been also found. The obtained results are also compared to some previous works.

关键词： ferrimagnetic mixed Ising system effective field theory hysteresis loops compensation behaviors

Characteristics of la-modified Ni-Al_2O_3 and Ni-SiO_2 catalysts for CO_x-free hydrogen production by catalytic decomposition of methane

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Journal of Energy Chemistry 2013年第6期22卷 853-860页

作者： Chatla Anjaneyulu Velisoju Vijay kumar Suresh k.Bhargava Ak.la Venugopal Inorganic & Physical Chemistry Division CSIR-Indian Institute of Chemical Technology College of Science Engineering and Health Advanced Materials & Industrial Chemistry School of Applied Sciences RMIT University

Hydrotalcite precursors of la modified Ni-Al2O3 and Ni-SiO2 catalysts prepared by co-precipitation method and the catalytic activities were examined for the production of COx-free H2 by CH4 decomposition. Physico-chemical characteristics of fresh, reduced and used catalysts were evaluated by XRD, TPR and O2 pulse chemisorptions, TEM and BET-SA techniques. XRD studies showed phases due to hydrotalcite-like precursors in oven dried form produced dispersed NiO species upon calcination in static air above 450 C. Raman spectra of deactivated samples revealed the presence of both ordered and disordered forms of carbon. Ni-la-Al2O3catalyst with a mole ratio of Ni : la : Al = 2 : 0.1 : 0.9 exhibited tremendously high longevity with a hydrogen production rate of 1300 molH2 mol 1 Ni. A direct relationship between Ni metal surface area and hydrogen yields was established.

关键词： CH4 decomposition Ni-la-Al hydrotalcite Ni metal surface area COx-free H2

New ternary superconducting compound laRu2As2： Physical properties from density functional theory calculations

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Chinese Physics B 2017年第3期26卷 453-460页

作者： M A Hadi M S Ali S H Naqib A k M A Islam Department of Physics University of Rajshahi Rajshahi 6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International Islamic University Chittagong Chittagong 4203 Bangladesh

In this paper, we perform the density functional theory （DFT） -based calculations by the first-principles pseudopo- tential method to investigate the physical properties of the newly discovered superconductor laRu2As2 for the first time. The optimized structural parameters are in good agreement with the experimental results. The calculated independent elas- tic constants ensure the mechanical stability of the compound. The calculated Cauchy pressure, Pugh＇s ratio as well as Poisson＇s ratio indicate that laRu2As2 should behave as a ductile material. Due to low Debye temperature, laRu2As2 may be used as a thermal barrier coating （TBC） material. The new compound should exhibit metallic nature as its valence bands overlap considerably with the conduction bands. laRu2As2 is expected to be a soft material and easily machinable because of its low hardness value of 6.8 GPa. The multi-band nature is observed in the calculated Fermi surface. A highly anisotropic combination of ionic, covalent and metallic interactions is expected to be in accordance with charge density calculation.

关键词： new superconductor laRu2As2 density functional theory (DFT) calculations mechanical proper-ties electronic features

Age of the Marwar Supergroup,NW India:A note on the U–Pb geochronology of Jodhpur Group felsic volcanics

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Geoscience Frontiers 2022年第1期13卷 244-254页

作者： Huiru Xu Joseph G.Meert Manoj k.Pandit Hubei Subsurface Multi-scale Imaging key laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China Department of Earth and Planetary Sciences University of FloridaGainesvilleFL 32611United States Department of Geology University of RajasthanJaipur 302004India

The Marwar Supergroup(NW Peninsular India)is thought to be of Ediacaran-Cambrian age,based on previous paleontological and geochronological ***,direct constraints on the onset of sedimentation within the Marwar basin are still *** this study,we report U–Pb zircon,la-ICP-MS,and SIMS ages from the Chhoti khatu felsic volcanic rocks,interlayered with the Jodhpur Group sandstones(Lower Marwar Supergroup).The cathodoluminescence images of the zircons indicate complex morphologies,and core-rim textures coupled with the wide range of ages indicate that they are likely inherited or in the case of thin poorly indurated ash-beds,detrital in *** age spectra of 68 zircon analyses from our sampling display a dominant 800–900 Ma age peak corresponding to the age of basement"Erinpura granite"rocks in the *** youngest inherited zircon from a felsic ash layer yielded a U–Pb age of651 Ma±18 Ma that,together with previous studies and paleontological evidence,indicates a postCryogenian age for the initiation of Marwar sedimentation following a~125 Ma hiatus between the end of Malani magmatism and Marwar deposition.

关键词： Marwar Supergroup Sedimentation age Zircon U-Pb dating Chhoti khatu felsic volcanics

Diversifying Resistance Mechanisms in Cereal Crops Using Microphenomics

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Plant Phenomics 2023年第1期5卷 1-5页

作者： Peter M.Dracatos Stefanie Lück Dimitar k.Douchkov Department of Animal Plant and Soil SciencesAgriBioLa Trobe UniversityBundooraVIC 3086Australia Leibniz Institute of Plant Genetics and Crop Plant Research(IPk)Gatersleben Corrensstrasse 306466 Seeland OT GaterslebenGermany

hole-grain cereals,including wheat,barley,oat,rye,corn,rice,millet,and triticale,are a rich source of calories,essential vitamins,minerals,and phytochemicals that both nourish and protect humans and animals from diseases such as heart attack and cancer[1].However,susceptibility to foliar diseases caused by necrotrophic or biotrophic fungal pathogens continues to reduce yield potential or lead to total crop failure and famine in developing nations[2].Historically,foliar diseases of cereals have been controlled using either fungicide treatment[3]or plant breeding[4].

关键词： breeding cereal corn

Microstructure and mechanical properties of spark plasma-sintered la_(2)O_(3) dispersion-strengthened W-Ni-Fe alloy

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Rare Metals 2021年第8期40卷 2230-2236页

作者： Muthuchamy AyyappaRaj Digvijay Yadav Dinesh k.Agrawal Raja Annamalai Arunjunai Rajan School of Mechanical Engineering VITVellore632014India Materials Research Institute University ParkPennsylvaniaPA16802USA Centre for Innovative Manufacturing Research VITVellore632014India

An investigation of lanthanum oxide(la_(2)O_(3))addition to tungsten heavy alloy(WHA)with a ternary composition of W-7 Ni-3 Fe was reported in this *** mixed powders were sintered using spark plasma sintering(SPS)***_(2)O_(3)was added in increments of 0.25 wt%,0.50 wt%,0.75 wt%and 1.00 wt%to WHA,*** sintered samples were characterized for microstructural evolution and mechanical *** influences of la_(2)O_(3)addition on density,grain size,hardness,ultimate tensile strength(UTS)and ductility on W-7 Ni-3 Fe system were discussed in this *** highest relative sintered density of 87.95%was obtained for 0.25 wt%la_(2)O_(3)addition to W-7 Ni-3 *** lowest grain size of 7.89μm was observed for 1.00 wt%la_(2)O_(3)***,the highest hardness and UTS of HV 533 and1110 MPa,respectively,were also obtained for the same *** electron microscopy(SEM)and energy-dispersive spectroscopy(EDS)of the samples revealed homogenous distribution of la_(2)O_(3)in the alloy *** of the sintered alloy samples revealed W-W intergranular fracture.

关键词： Tungsten heavy alloys lanthanum oxide Spark plasma sintering Microstructure Mechanical properties

Green mediated synthesis of lanthanum doped zinc oxide:Study of its structural,optical and latent fingerprint application

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Journal of Rare Earths 2020年第12期38卷 1281-1287页

作者： H.N.Shivananjaiah k.Sailaja kumari M.S.Geetha Government Science College Nrupatunga RoadBangalore560001India Base Educational Services BasavanagudiBangalore560004India

The present paper summarises the synthesis of la3+doped zinc oxide nanoparticles using Aloe vera gel by solution combustion method and the characterization using a powder X-ray diffractometer(PXRD),a transmission electron microscope(TEM),an X-ray photometric spectrometer(XPS),a Raman spectrometer and their applications in optical devices and latent *** pattern confirms the crystallite size of la3+doped ZnO varies from 13 to 20 *** size varies inversely with doping *** properties are found to be the maximum for 2 mol% doping *** spectra extends the use of ZnO:la3+nanoparticles in blue green *** nanoparticles also have superior property as a fluorescent labels in fingerprints.

关键词： Green synthesis Nanostructures Photoluminescence latent fingerprinting Rare earths

Characterization of Woody Vegetation in Different land Uses in the Commune of Coubalan (Bignona Department, Senegal)

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American Journal of Plant Sciences 2023年第11期14卷 1343-1359页

作者： Francis Artur Gomez Ismaïla Coly Arfang Ousmane kémo Goudiaby Mohamed Ndao Agroforestry and Ecology laboratory (laFE) Department of Agroforestry Assane Seck University Ziguinchor Senegal

Woody vegetation provides a number of ecosystem services, including soil protection, carbon sequestration and oxygen production. Despite its important role in maintaining ecological balance, woody vegetation is currently undergoing continuous degradation due to climatic hazards and anthropogenic actions. As a result, it is essential to gather information for the sustainable and rational management of woody formations. It is with this in mind that this study aims to contribute to a better understanding of the state of woody vegetation in the different land-use types in Basse Casamance. To this end, stratified random sampling of woody vegetation was carried out in the different land-use types (fields, fallow land and forests) of the Coubalan commune. The sampling unit for fields and fallows was a 2500 m2 plot, and for forests was a 900 m2 plot. A total of 53 species, divided into 48 genera belonging to 22 families, were inventoried in the commune. Structural parameters were higher in the forest, with 1321.3 ± 635.8 individuals/ha, 13.09 ± 0.1 m2 and 79.25% ± 21.08% respectively for observed density, basal area and cover rate. As for dendrometric parameters, they are higher in the fields, with 20.4 ± 13.6 cm and 7.4 ± 3.8 m respectively for trunk diameter and woody height. Fallow land is characterized by species with low dendrometric parameters. These results provide a useful database for rational management of the various land-use types in the commune of Coubalan.

关键词： Lower Casamance Forest Fallow Field Woody Vegetation

Generalized Graph Ideals of Linear Type

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Algebra Colloquium 2017年第1期24卷 83-91页

作者： M. la Barbiera P.L. Stagliano Department of Mathematics University of MessinaViale Ferdinando Stagno d'A1contres 31 98166 Messina Italy

Let S = k[x1,..., xn; y1,..., ym] be the polynomial ring in two sets of variables over a field k. We investigate some classes of graph ideals of S, namely the generalized graph ideals, in order to classify ideals of l... 详细信息

关键词： ideals of mixed products graph ideals ideals of linear type