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Thermal bleaching of optical absorption and photoluminescence spectra of γ-irradiated CaF_2:Dy:Pb:Na single crystals

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Journal of Rare Earths 2010年第4期28卷 493-497页

作者： s.m. moses Kennedy Department of Physics S.S.N. College of Engineering Rajiv Gandhi Salai Kalavakkam-603 110 Chennai Tamil Nadu India

The variation of the optical absorption (OA) and photoluminescence (PL) spectra with temperature was studied on γ-irradiated CaF2:Dy:Pb:Na single crystals. The OA spectrum showed bands around 2.05, 3.20, 3.82 and 6.20 eV which could be attributed to different sodium associated (sA) colour centres (CCs) such as.m.a and RA+ . Heating the crystal indicated the annihilation and formation of different sACCs. The excitation spectrum for the characteristic Dy3+ emission at 2.14 eV immediately after irradiation was...

关键词： calcium fluoride optical absorption photoluminescence colour centres dysprosium lead sodium rare earths

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Effects of CO_2 content on the activity and stability of nickel catalyst supported on mesoporous nanocrystalline zirconia

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Journal of Natural Gas Chemistry 2008年第3期17卷 278-282页

作者： m. Rezaei s.m. Alavi s. sahebdelfar Zi-Feng Yan Chemical Engineering Department Faculty of Engineering University of Kashan Iran Chemical Engineering Department lran University of Science and Technology Tehran Iran Petrochemical Research ＆ Technology Company （NPC-RT） Tehran Iran state Key Laboratory for Heavy Oil Processing Key Laboratory of Catalysis CNPC China University of Petroleum Dongying 257061 Shandong China

The effects of carbon dioxide content on the catalytic performance and coke formation of nickel catalyst supported on mesoporous nanocrystalline zirconia with high surface area and pure tetragonal crystalline phase were investigated in methane reforming with carbon dioxide. The s.m.les were characterized by XRD, BET, TPR, TPO, TPH, TEm, and s.m.techniques. The catalyst prepared showed high surface area and a mesoporous structure with a narrow pore size distribution. The obtained results revealed that the increase in CO2 content increased the methane conversion and stability of the catalyst and significantly reduced the coke deposition. The TPH analysis showed that several species of carbon with different reactivities toward hydrogenation were deposited on the spent catalysts employed under different CO2 contents.

关键词： Ni catalysts carbon dioxide reforming coke deposition

Dielectric Behavior of modified Cellulose

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Journal of materials science & Technology 1999年第2期15卷 164-168页

作者： El-Henawii, s.A. saad, s.m. El-Anwar, I.m. Faculty of science Helwan University Egypt Chemistry Department Faculty of Science Al-Azhar University Egypt Physical Chemistry Unit of the N.R.C Egypt

The dielectric constants and the dielectric loss, as well as the activation energy of dielectric relaxation of silylated cellulose were measured within the frequency range 10**5 to 10**7 Hz and the temperature range from 10 to 50 degree C. The test s.m.les were activated cellulose with ethylene diamine, with sodium hydroxide and inactivated cellulose before and after silylation. The measurements were carried out using a multi-deka-meter. Cellulose molecules are more activated by treatment with ethylene diamine than with sodium hydroxide. Generally, silylation causes a marked decrease of the dielectric constant and dielectric loss, meanwhile the silylated s.m.les are affected with the pretreatment of linters with sodium hydroxide and ethylene diamine. (Edited author abstract) 28 Refs.

关键词： Cellulose

A comprehensive investigation of loading variance influence on fuel cons.m.tion and gas emissions in mine haulage operation

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International Journal of mining science and Technology 2016年第6期26卷 995-1001页

作者： soofastaei A. Aminossadati s.m. Kizil m.s. Knights P. school of mechanical and mining Engineering University of Queensland

The data collected from haul truck payload management systems at various surface mines show that the payload variance is significant and must be considered in analysing the mine productivity, diesel energy cons.m.tion, greenhouse gas emissions and associated costs. The aim of this study is to determine the energy and cost saving opportunities for truck haulage operations associated with the payload variance in surface mines. The results indicate that there is a non-linear relationship between the payload variance and the fuel cons.m.tion, greenhouse gas emissions and associated costs. A correlation model, which is independent of haul road conditions, has been developed between the payload variance and the cost saving using the data from an Australian surface coal mine. The results of analysis for this particular mine show that a significant saving of fuel and greenhouse gas emissions costs is possible if the standard deviation of payload is reduced from the maximum to minimum value.

关键词： Energy cons.m.tion Haul truck surface mine Greenhouse gas emissions Cost

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros.m.ñé Laia Just-Borràs.m.rta Balanyà-segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina silvera-s.m.n manel m.santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we s.m.arize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur s.m.ltaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Effects of Isotopic Concentrations on Thermodynamic Parameters of Deuterium-Tritium mixtures

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Communications in Theoretical Physics 2013年第7期60卷 108-112页

作者： s.m. motevalli m.R. Pahlavani m. Azimi Department of Nuclear Physics Faculty of Science University of Mazandaran

Thermodynamic estimation is still too much requested for scientific applications in spite of great advances in s.m.lation methods for efficient determination of phase equilibrium of multi-component systems. In this work, thermodynamic properties of deuterium-tritium mixture in a wide range of temperatures and pressures have been predicted. Buckingham exp-6 potential has been utilized in calculations, based on statistical perturbation theory. The effects of various values of density, temperature and isotopic concentrations on pressure have been studied. Eventually, we have found out s.m.etrical effects of tritium concentration in deuterium-tritium mixtures.

关键词： Deuterium-tritium mixture thermodynamic property buckingham exp-6 potential Tritium concentration

Deforestation effects on biological and other important soil properties in an upland watershed of Bangladesh

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Journal of Forestry Research 2014年第4期25卷 877-885页

作者： s.m. sirajul Haque sanatan Das Gupta sohag miah Institute of Forestry and Environmental sciences University of Chittagong Chittagong 4331 Bangladesh Department of Renewable Resources University of Alberta EdmontonCanada Research Fellow Institute of Forestry and Environmental SciencesUniversity of Chittagong Chittagong-4331 Bangladesh

Deforestation occurs at an alarming rate in upland watersheds of Bangladesh and has.m.ny detrimental effects on the environment. This study reports the effects of deforestation on soil biological proper- ties along with s.m. important physicochemical parameters of a southern upland watershed ***. soils were s.m.led at 4 paired sites, each pair representing a deforested site and a forested site, and having s.m.lar topographical characteristics. significantly fewer （p〈0.001） fungi and bacteria, and lower microbial respiration, active microbial biomass, metabolic and microbial quotients were found in soils of the deforested sites. soil physical properties such as.m.isture content, water holding capacity, and chemical properties such as organic matter, total N, avail- able P and EC were also lower in deforested soils. Bulk density and pH were significantly higher in deforested soils. Available Ca and mg were inconsistent between the two land uses at all the paired sites. Re- duced abundance and＇biomass of soil mesofauna were recorded in defor- ested soils. However, soil anecic species were more abundant in defor- ested soils than epigeic and endogeic species, which were more abundant in forested soils than on deforested sites.

关键词： deforestation effeets biological properties soil animals upland watershed Bangladesh

Thermogravimetric studies of Deposited Potash Impregnated for Flame-Retardancy into a Cotton Fabric

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Chinese Journal of Chemistry 2007年第7期25卷 926-929页

作者： mOsTAsHARI, s.m. NIA, Y.K. BALE, s. Department of Chemistry Faculty of Science the University of Gilan Rasht lran

The effect of potash as a nondurable finish on the flammability of 100% cotton fabric （plain 180 g/m^2） was investigated. The bone-drled weighed fabrics were dipped into suitable concentrations of potash, with a volume of 100 mL at 20-2℃. The impregnation was followed by means of squeeze rolls and drying at 110 ℃. The s.m.les were then reweighed with analytical precision. After conditioning overnight by using our ＂vertical flame tester＂ the optimum add-on values to impart flame-retardancy to cotton fabric was determined and expressed by 0.80 g of potash per 100 g fabric to be an efficient addition. Thermogravimetric analysis of pure cotton, treated cotton with potash at its optimum efficiency for donation of flame-retardancy into cotton fabric was fulfilled and the thermograms were compared and commented. The effectiveness of this hydroxide was attributed to the heat dissipation by the remaining cons.m.d material during the combustion. The results obtained are in favor of ＂Dust or Wall Effect Theory＂.

关键词： condensed phase retardation dust or wall effect theory flame-retardancy gas theory potash thermogravimetry