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Investigation of 50 Hz Pulsed DC Nitrogen Plasma with Active Screen Cage by Trace Rare Gas Optical Emission Spectroscopy

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Plasma Science and Technology 2014年第4期16卷 324-328页

作者： A.SAEED A.w.KHAN m.SHAFIQ F.JAN m.ABRAR m.ZAKA-UL-ISLAm m.ZAKAULLAH Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Plasmant Department of Chemistry Univesity of Antwerp campus DriEkin

Optical emission spectroscopy is used to investigate the nitrogen-hydrogen with trace rare gas （4% Ar） plasma generated by 50 Hz pulsed DC discharges. The filling pressure varies from 1 mbar to 5 mbar and the current density ranges from 1 mA-cm-2 to 4 ***-2. The hydrogen concentration in the mixture plasma varies from 0% to 80%, with the objective of identifying the optimum pressure, current density and hydrogen concentration for active species （[N] and IN2]） generation. It is observed that in an N2-H2 gas mixture, the concentration of N atom density decreases with filling pressure and increases with current density, with other parameters of the discharge kept unchanged. The maximum concentrations of active species were found for 40% H2 in the mixture at 3 mbar pressure and current density of 4 ***-2.

关键词： TRG-OES DC glow discharge reactive species

Effects of Terminalia catappa seeds on sexual behaviour and fertility of male rats

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Asian Journal of Andrology 2000年第3期2卷 213-219页

作者： w.D.Ratnasooriya m.G.Dharmasiri Department of Zoology University of Colombo Colombo 3 Sri LankaDepartment of Zoology University of Colombo Colombo 3 Sri Lanka

Aim: To evaluate the aphrodisiac potential of Terminalia catappa Linn. seeds using a suspension of its kernel (SS)in 1% methyl cellulose in rats. methods: male rots were orally treated with 1500 mg/kg or 3000 mg/kg SS or ve-hicle, and their sexual behaviour was monitored 3 h later using a receptive female. Another group of rats was orallytreated with either 3000 mg/kg SS or vehicle for 7 consecutive days. Their sexual behaviour and fertility were evaluatedon days 1, 4 and 7 of treatment and day 7 post-treatment by pairing overnight with a pro-oestrous female. Results:The 1500 mg/kg dose, had a marked aphrodisiac action (prolongation of ejaculation latency) but no effect on libido(% mounting, % intromission and % ejaculation), sexual vigour (mounting-and-intromission frequency), or sexualperformance (intercopulatory interval). In contrast, the higher dose (3000 mg/kg) reversibly inhibited all the para?e-ten of sexual behaviour other than mounting-and-intromission frequency and copulatory efficiency. The effects of highdose SS were not due to general toxicity, liver toxicity, haemotoxicity, stress, muscle deficiency, muscle incoordina-fion, analgesia, hypoglycaemia or reduction in blood testosterone level. They were due to marked sedation. Conclu-sion: The kernel of T. catappa seeds has aphrodisiac activity and may be useful in the treatment of certain forms ofsexual inadequacies, such as premature ejaculation.

关键词： Terminalia catappa seeds aphrodisiac male sexual behaviour libido premature ejaculation fertility sedation

measurement of the pion form factor for m_(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOE detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan E.müller Institut für Kernphysik Johannes Gutenberg-Universitt

The KLOE experiment at the φ-factory DAФPNE has measured the pion form factor in the range between 0.1 〈 mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the mππ^2 region covered by KLOE ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

Dehydration Kinetics of Embryonic Axes from Desiccation-sensitive Seeds:An Assessment of Descriptive models

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Journal of Integrative Plant Biology 2009年第11期51卷 1002-1007页

作者： Tobias m. Ntuli Norman w. Pammenter School of Biological and Conservation Sciences University of KwaZulu-NatalWestville Campus

The response of desiccation-sensitive plant tissues to dehydration is significantly affected by dehydration conditions, particularly the rate of drying. Consequently it is important to be able to quantify drying rate. The aim of the study was to assess two models that have been proposed to describe drying kinetics, and thus to provide a quantification of non-linear drying rates, of embryonic axes excised from recalcitrant seeds. These models are an exponential drying time course, and a modified inverse relationship, respectively. For the six species investigated here the inverse function was generally found to fit drying data better than the exponential function under both rapid and slow drying conditions, and so is recommended. The rate of drying, under the conditions used here, was determined by axis size and possibly the nature of the axis outer coverings, rather than the water activity difference between the tissue and surrounding air.

关键词： desiccation drying rate recalcitrant seeds.

L-arginine, the substrate of nitric oxide synthase,inhibits fertility of male rats

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Asian Journal of Andrology 2001年第2期3卷 97-103页

作者： w.D.Ratnasooriya m.G.Dharmasiri Department of Zoology University of Colombo Colombo 3 Sri LankaDepartment of Zoology University of Colombo Colombo 3 Sri Lanka

Aim: To examine the effect of L-arginine, the substrate of nitric oxide (NO) synthase, on reproductive function ofmale rats. methods: male rats were gavaged with either L-arginine (100 or 200 mg·kg^(-1)·d^(-1)), D-arginine (200mg·kg^(-1)·d^(-1)) or vehicle (0.9% NaCl) for seven consecutive days. Their sexual behaviour and fertility were evaluat-ed using receptive females. Results: L-arginine (200 mg/kg) had no significant effect on sexual competence (interms of sexual arousal, libido, sexual vigour and sexual performance). In mating experiments, the higher dose of L-arginine effectively and reversibly inhibited fertility, whilst the lower dose and the inactive stereoisomer D-arginine hadno significant effect. The antifertility effect caused by L-arginine was due to a profound elevation in the preimplantationloss mediated possibly by impairment in epididymal sperm maturation, hyperactivated sperm motility and sperm capaci-tation. Conclusion: Elevated NO production may be detrimental to male fertility.

关键词： L-arginine nitric oxide fertility libido sex behavior pre-implantation loss sperm motility contraceptives

Carrier Density and Electric Field Dependent Nonlinear Transport of Chemical Vapor Deposition Graphene

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Chinese Physics Letters 2013年第3期30卷 127-130页

作者： KHALIL Hafiz m.w. KELEKCI Ozgur NOH Hwayong Department of Physics and Graphene Research Institute Sejong UniversitySeoul 143-747Korea

we report on the measurements of nonlinear current-voltage characteristics of graphene fabricated by chemical vapor *** current-voltage characteristic is described by a power law with a superlinear dependence of the current on the voltage,and the nonlinearity depends on the carrier density and the excitation *** nonlinearity is strongest at the Dirac point and becomes weaker as the carrier density *** the Dirac point,we also observe a crossover to a much stronger nonlinear transport when the electric field increases above 104 V/m.

关键词： deposition. nonlinearity nonlinear

Non-Thermal Effects on CO-NO Surface Catalytic Reaction on Square Surface： monte Carlo Study

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Chinese Physics Letters 2005年第6期22卷 1533-1535页

作者： m.Khalid A.U.Qaisrani w.Ahmad DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan PhysicsResearchDivision PakistanInstituteofNuclearScienceandTechnologyPONiloreIslamabadPakistan

A monte Carlo simulation of the CO-NO heterogeneous catalytic reaction over asquare surface has already been studied with a model based on the Langmuir-Hinshelwood (LH)mechanism. The results of this study are well known. Here we study the effects of transientnon-thermal mobility of monomer (CO) based on precursor mechanism, diffusion of adsorbed nitrogenand oxygen atoms, on the phase diagram. The interesting feature of this model is the yield of asteady reactive window, while simple LH mechanism is not capable of producing a steady reactivestate.

关键词： PRECURSOR mECHANISm HEXAGONAL SURFACES PHASE-DIAGRAm SImULATION SUBSURFACE mODEL CHEmISORPTION NITROGEN TUNGSTEN LATTICE

Synthesis and characterization of lithium niobium borate glasses containing neodymium

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Journal of Rare Earths 2016年第12期34卷 1199-1205页

作者： w.H.A.Kamaruddin m.S.Rohani m.R.Sahar LIU Hong SANG Yuanhua AOmRG Lab Physics Department Faculty of Science Universiti Teknologi Malaysia State Key Laboratory of Crystal materials Shandong University

A series of（90–x）Li2B4O7-10Nb2O5-xNd2O3 glass samples（x=0, 5 mol.%, 10 mol.%, 15 mol.%, 20 mol.% and 25 mol.%） were synthesized using melt quenching technique. X-ray diffraction（XRD）, differential thermal analyzer（DTA）, Fourier transformed infrared（FTIR）, ultraviolet-visible-near-infrared（UV-Vis-NIR） spectrometer and photoluminescence（PL） spectroscopic characterizations were made to examine the influence of Nd3＋ concentration on the physical, structural and optical properties. Various physical properties such as glasses density, molar volume, thermal stability, ion concentration, polar on radius, inter-nuclear distance, field strength, cut-off wavelength, energy band gap and Urbach energy were calculated. The samples were amorphous in nature and confirmed from XRD pattern. The FTIR spectra revealed the presence of BO3 and BO4 functional groups. UV-Vis-NIR spectra exhibited nine prominent bands centered at 353, 430, 475, 524, 583, 681, 745, 803, 875 nm corresponding to the transitions from the ground state to ^4D（3/2）, ^2P（1/2）, ^2G（9/2）, ^4G（7/2）, ^4G（5/2）, ^4F（9/2）, ^4F（7/2）, ^4F（5/2）, ^4F（3/2） excited states, respectively. moreover, the emission spectra at 355 nm excitation displayed three peaks centered at 903 nm（^4F（3/2）→^4I（9/2））, 1059 nm（^4F（3/2）→^4I（11/2）） and 1333 nm（^4F（3/2）→^4I（13/2））, respectively. Fluorescence lifetime was recorded between 53.69 to 28.43 μs. It was found that varying concentration of Nd^（3＋） ions strongly affected the physical, structural and optical properties of the glass samples.

关键词： borate glass neodymium optical properties band gap luminescence rare earths

Developing a two-decadal time-record of rice field maps using Landsat-derived multi-index image collections with a random forest classifier:A Google Earth Engine based approach

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Information Processing in Agriculture 2024年第2期11卷 260-275页

作者： w.Ashane m.Fernando I.P.Senanayake Department of Nano Science Technology Wayamba University of Sri LankaKuliyapitiya 60200Sri Lanka Dchoolf Engineing CllegeoEngineeringSience and EnionmentThe UniversyewcastleCallaghanW2Austraia

Historic maps showing the temporal distribution of rice fields are important for precision agriculture,irrigation optimisation,forecasting crop yields,land use management and formulating ***,mapping rice felds using traditional ground surveys is impractical when high cost,time and labour requirements are considered,and the availability of such detailed records is *** satellite remote sensing appears to be a viable solution,conventional segmentation and classification methods with spectral bands are often unable to contrast the distinct characteristics between rice fields and other vegetation *** this end,we explored a novel,Google Earth Engine(GEE)based multiindex random forest(RF)classification approach to map rice fields over two *** images from 2000 to 2020 of two Sri Lankan rice cultivation districts were extracted from GEE and a multi-index RF classification algorithm was applied to distinguish the rice *** results showed above 80%accuracy for both training and validation,when compared against high spatial resolution Google Earth *** essence,multi-index sampling and RF together synergised the compelling classifcation accuracy by effectively capturing vegetation,water(ponding)and soil characteristics unique to the rice felds using a single-click *** maps developed in this study were further compared against the mODIS land cover type product(mCD12Q1)and the corresponding superior statistics on rice fields demonstrated the robustness of the proposed *** work seeking effective index combinations is recommended,and this approach can potentially be extended to other crop analyses elsewhere.

关键词： Google Earth Engine(GEE) Image classification Random forest mapping rice fields Time series analysis Vegetation index