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Defence Technology（防务技术） 2019年第1期15卷 111-121页

作者： c.V.s.Murthy A.gopala Krishna g.M.Reddy Defence Research and Development Laboratory Jawaharlal Nehru Technological University Defence Metallurgical Research Laboratory

Maraging steel (250) and 13-8 Mo stainless steel plates were joined by gas tungsten constricted arc welding(gTcAW) process in similar and dissimilar metal combinations using 13-8 Mo stainless steel filler wire. The similar and dissimilar metal welds made in solutionized condition were subjected to standard post weld hardening treatments direct ageing at 485 ℃, soaking for 31/2 hours followed by air cooling(ageing treatment of maraging steel) and direct ageing at 510 ℃, soaking for 4 h followed by air cooling(ageing treatment of 13-8 Mo stainless steel). The joint characterization studies include microstructure examination, microhardness survey across the weldments and transverse weld tensile *** and dissimilar metal weldments responded to both the post weld ageing treatment. After post weld aging, increase in yield strength, UTs and slight reduction in % elongation of similar and dissimilar metal were observed. The observed tensile properties were correlated with microstructure and hardness distribution across the welds.

关键词： Maraging steel(250) 13-8 Mo stainless steel Mechanical properties Microstructure

Kinetics of thermal decomposition of hydrated minerals associated with hematite ore in a fluidized bed reactor

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 229-239页

作者： P.c. Beuria s.K. Biswal B.K. Mishra g.g. Roy Institute of Minerals and Materials Technology Council of Scientific & Industrial Research Bhubaneswar-751013 India Indian Institute of Technology Kharagpur-721302 India

The kinetics of removal of loss on ignition(LOI) by thermal decomposition of hydrated minerals present in natural iron ores(i.e.,kaolinite,gibbsite,and goethite) was investigated in a laboratory-scale vertical fluidized bed reactor(FBR) using isothermal methods of kinetic *** in the FBR in batch processes were carried out at different temperatures(300 to 1200°c) and residence time(1 to 30 min) for four different iron ore samples with various LOIs(2.34wt% to 9.83wt%).The operating velocity was maintained in the range from 1.2 to 1.4 times the minimum fluidization velocity(Umf).We observed that,below a certain critical temperature,the FBR did not effectively reduce the LOI to a desired level even with increased residence *** results of this study indicate that the LOI level could be reduced by 90% within 1 min of residence time at 1100°*** kinetics for low-LOI samples(cates two different reaction mechanisms in two temperature *** lower temperatures(300 to 700°c),the kinetics is characterized by a lower activation energy(diffusion-controlled physical moisture removal),followed by a higher activation energy(chemically controlled removal of LOI).In the case of high-LOI samples,three different kinetics mechanisms prevail at different temperature *** temperature up to 450°c,diffusion kinetics prevails(removal of physical moisture);at temperature from 450 to 650°c,chemical kinetics dominates during removal of matrix *** temperatures greater than 650°c,nucleation and growth begins to influence the rate of removal of LOI.

关键词： thermal decomposition fluidized beds kinetic analysis hydrated iron ore activation energy

study on kinetics of thermal decomposition of low LOI goethetic hematite iron ore

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International Journal of Mining science and Technology 2017年第6期27卷 1031-1036页

作者： Beuria P.c. Biswal s.K. Mishra B.K. Roy g.g. Mineral Processing Department CSIR–Institute of Minerals and Materials TechnologyBhubaneswar 751013India Indian Institute of Technology Kharagpur 721302India

In the present study, the kinetics of thermal decomposition of hydrated minerals associated in natural hematite iron ores has been investigated in a fixed bed system using isothermal methods of kinetic analysis. Hydrated minerals in these hematite iron ores are kaolinite, gibbsite and goethite, which contribute to the loss on ignition(LOI) during thermal decomposition. Experiments in fixed bed have been carried out at variable bed depth(16, 32, 48 and 64 mm),temperature(400-1200 ℃) and residence time(30,45, 60 and 75 min) for iron ore samples. It is observed that beyond a certain critical bed depth(16 mm), 100% removal of LOI is not found possible even at higher temperature and higher residence time. Most of the solid-state reactions of isothermal kinetic analysis have been used to analyze the reaction mechanism. The raw data are modified to yield fraction reacted "α" versus time and used for developing various forms of "α" functions.f(α) is the inverse of first derivative of g(α) with respect to α. The study demonstrates that decomposition of hydrated mineral in hematite follows the chemical *** estimated activation energy values in all the experimental situations are found to high, of the order of 60 kJ/mol, reinstating that the reactions are indeed controlled by moving phase boundary and random nucleation.

关键词： Loss on ignition goethite Kaolinite gibbsite Roasting Pellet feed Kinetic analysis

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-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs carolina silvera-simón 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 summarize 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 simultaneously 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

First episode psychosis with extrapyramidal signs prior to antipsychotic drug treatment

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chinese science Bulletin 2011年第32期56卷 3361-3371页

作者： HONER William g LANg Donna J KOPALA Lili c MAcEWAN g William smith geoffrey N cHEN Eric Y H cHAN Raymond c K Department of Psychiatry University of British Columbia Vancouver BC Canada Department of Radiology University of British Columbia Vancouver BC Canada Department of Psychiatry Dalhousie University Halifax NS Canada Department of Psychiatry University of Hong Kong Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences

Extrapyramidal movement disorders are common in chronic schizophrenia, and may be an intrinsic feature of the illness as well as related to antipsychotic drug treatment. similar dysfunctions at illness onset may have implications for outcome, and for under- standing the mechanisms of illness. The objectives were to examine the clinical correlates of pre-treatment movement disorders at first episode of psychosis, and determine associations with neuropsychological function and striatal structure. Never medicated subjects were recruited from consecutive admissions to Early Psychosis Programs with defined catchment areas in Hong Kong, china, and Halifax, canada. standardized clinical, neuropsychological and brain imaging assessments were carried out at baseline and following acute and long term treatment with typical or atypical antipsychotic drugs. At the Hong Kong site, we studied 84 subjects with first episode psychosis (n = 10 with EPs). At the Halifax site, we studied 40 subjects with first episode psychosis (n = 17 with EPs), and 23 healthy comparison subjects. subjects with movement disorders prior to treatment (EPs+) had higher total PANss scores at baseline (mean elevation 19.9% Hong Kong, P = 0.016; 14.7% Halifax, P = 0.049). In subjects treated with atypical antipsychotics (all Halifax), EPs+ status at baseline predicted more movement disorders at long term follow up (P = 0.0005). In both cohorts, EPs+ subjects had poorer acute symptomatic treatment response assessed with the PANss (Hong Kong P = 0.005; Halifax P = 0.017). Neuropsychological impairment related to executive dysfunction appeared greater in a small sam- ple of EPs+ subjects (Hong Kong, effect size 0.26-0.27, P caudate volumes were 4.5% larger in EPs+ compared with EPs-subjects (Halifax P = 0.042), and correlations between striatal volumes and age were different in the EPs+ group. In conclu- sion, pre-treatment EPs is present in a substantial minority of subjects with first episode psych

关键词：药物治疗精神病体外症状运动障碍每股收益神经功能精神分裂症

Neutrino masses,cosmological inflation and dark matter in a variant U(1)B-L model with type II seesaw mechanism

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chinese Physics c 2021年第2期45卷 621-630页

作者： J.g.Rodrigues A.c.O.santos J.g.Ferreira Jr c.A.de s.Pires Departamento de Física Universidade Federal da ParaíbaCaixa Postal 500858051-970João PessoaPBBrasil Departamento de Física Universidade Federal do Rio Grande do Norte59078-970NatalRNBrasil

In this study,we implemented the type Ⅱ seesaw mechanism into the framework of the U(l)B-L gauge *** achieve this,we added a scalar triplet,A,to the canonical particle content of the U(l)B-Lgauge *** imposing that the U(l)B-L gauge symmetry be spontaneously broken at TeV scale,we show that the type Ⅱ seesaw mechanism is realized at an intermediate energy scale,more precisely,at approximately 109 *** prevent heavy right-handed neutrinos from disturbing the mechanism,we evoke a Z2 discrete ***,as a result,we have standard neutrinos with mass around eV scale and right-handed neutrinos with mass in TeV scale,with the lightest one fulfilling the condition of dark *** developed all of these in this *** addition,we show that the neutral component of Δ may perform unproblematic non-minimal inflation with loss of unitarity.

关键词： models beyond the standard model particle-theory and field-theory models of the early universe neutrino mass and mixing

Improved Osteointegration of Ti-6Al-4V-implants of Different surface Texture by the Use of Bone Morphogenetic Protein-3 (BMP-3)

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Journal of Wuhan University of Technology(Materials science) 2005年第B12期20卷 301-303页

作者： Esenwein s A Esenwein s Herr g Hauser J Muhr g Hartwig c-H Department of surgery BG Trauma Center Bergmannsheil University Hospital Buerkle-de-la-Camp-Platz 1 D-44789 Bochum Germany Dental Practice Am Obstmarkt 5 D-71522 Backnang Germany Advanced Tissue Regeneration gmbH Turmstr. 16 D-35578 Wetzlar Germany Department of Orthopaedics Michaelis-Hospital Eichenstrasse 34 D-20244 Hamburg Germany

Half of altogether 60 cylindrical implant devices made of titanium-aluminum-vanadium alloy （ Ti-6Al-4V） were plusna-sprayed with a hydroxyapatite-couting and the other half had a corundum blasted porous surface. 15 implants of each group of the titanium test buplants were coated with 230 μg porcine, high-purified BMP- 3-precipitute per implant. In each case a BMP- 3-couted and an uncoated control-device were implanted into the femoral part of the putellofemoral joint of the right and left leg of 30 adult giant rabbits. Histomorphological and histomorphometrical we found in both groups with BMP- 3-coated test devices an improved osteointegrution. stutistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of tony formed bone of the BMP- 3-coated corundum- blasted or hydroxyapathe- coated Ti- 6Al- 4 V test devices compared to the non-couted controls of the same t）pe （p 〈 0.01, t-test for matched samples）. In both implant groups with BMP-couting a synergetic effect was verifiable although the bone ongrowth in the hydroxyaputite coated implants was more extensive than in the corundum blasted implants. Light microscopy demonstrated osteointegrution without connective tissue membrane around the surface of the implants. Our results indicate that composite metal implants,as used in endoprosthetics and implantology , are suitable carriers for BMP- 3 and im proved fixation of the implants can be achieved. The hydroxyapatite surface is superior to the corundum-blasted surface with regards to the observed parameters because of its pronounced bioactivity and its osteoconductive characteristics.

关键词： bone morphogenetic protein-3 BMP- 3 hydroxyapatite osteointegration surface coating bone ingrowth implantology

Biodegradation of crystal Violet by Agrobacterium radiobacter

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Journal of Environmental sciences 2011年第8期23卷 1384-1393页

作者： g.K.Parshetti s.g.Parshetti A.A.Telke D.c.Kalyani R.A.Doong s.P.govindwar Department of Biomedical Engineering and Environmental sciences National Tsinghua University Division of Applied Life sciences Gyeongsang National University Division of chemical Engineering Konkuk University Department of Biochemistry Shivaji University

Agrobacterium radiobacter MTcc 8161 completely decolorized the crystal Violet with 8 hr （10 mg/L） at static anoxic conditions. The decreased decolorization capability by A. radiobacter was observed, when the crystal Violet concentration was increased from 10 to 100 mg/L. semi-synthetic medium containing 1% yeast extract and 0.1% NH4c1 has shown 100% decolorization of crystal Violet within 5 hr. A complete degradation of crystal Violet by A. radiobacter was observed up to 7 cycles of repeated addition （10 rag/L）. When the effect of increasing inoculum concentration on decolorization of crystal Violet （100 mg/L） was studied, maximum decolorization was observed with 15% inoculum concentration. A significant increase in the activities of laccase （184%） and aminopyrine N-demethylase （300%） in cells obtained after decolorization indicated the involvement of these enzymes in decolorization process. The intermediates formed during the degradation of crystal Violet were analyzed by gas chromatography and mass spectroscopy （gc/Ms）. It was detected the presence of N,N,N＇,N＂-tetramethylpararosarfiline, IN, N-dimethylaminophenyl] [N-methylaminophenyl] benzophenone, N, N-dimethylaminobenzaldehyde, 4-methyl amino phenol and phenol. We proposed the hypothetical metabolic pathway of crystal Violet biodegradation by A. radiobacter. Phytotoxicity and microbial toxicity study showed that crystal Violet biodegradation metabolites were less toxic to bacteria （A. radiobacter, P. aurugenosa and A. vinelandii） contributing to soil fertility and for four kinds of plants （sorghum bicolor, Vigna radiata, Lens culinaris and Triticum aestivum） which are most sensitive, fast growing and commonly used in Indian agriculture.

关键词： Agrobacterium radiobacter crystal Violet biodegradation gas chromatography and mass spectroscopy toxicity study

sintering and mechanical properties of β-sic powder obtained from waste tires

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Journal of Advanced ceramics 2016年第1期5卷 40-46页

作者： g.MAgNANI s.gALVAgNO g.sIcO s.PORTOFINO c.FREDA E.BURREsI ENEA SSPT-PROMAS-TEMAF Faenza Research Laboratories Via Ravegnana 186 48018 Faenza(RA) Italy ENEA SSPT-PROMAS-NANO Portici Research Center P.le Enrico Fermi 1 80055 Portici(NA) Italy ENEA SSPT-PROMAS-MATAS Brindisi Research Center S.S.7 Appia km 70600 72100 Brindisi Italy

Plasma synthesized sic powder obtained from quartz and carbonaceous residue of waste tires was successfully sintered at 1925 ℃ by pressureless liquid-phase method using yttria and alumina as sintering aids (T-sic). comparison with sintered sic obtained from commercial powder (c-sic) put in evidence of similar sintered density (98%T.D.), but much finer microstructure of T-sic than that of c-sic. T-sic also showed higher flexural strength than c-sic both at room temperature (508 vs. 458 MPa) and at 1500 ℃ (280 vs. 171 MPa). Difference in liquid phase was responsible for the differences in hardness and fracture toughness. The high value of the Young’s modulus of T-sic (427 MPa) confirmed the high degree of sinterability of this powder and that it can be a promising candidate for structural applications with high added value.

关键词： sintering mechanical properties sic structural application

chemical-structural changes of Organic Matter in a semi-Arid soil After Organic Amendment

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Pedosphere 2012年第3期22卷 283-293页

作者： c.NIcOLs g.MAscIANDARO T.HERNNDEZ c.gARcIA centro de Edafología y Biología Aplicada del segura (cEBAs-csIc) Department of Soil and Water Conservation and Organic Wastes ManagementCampus Universitario de EspinardoP.O.160Murcia 3010 (Spain) consiglio Nazionale delle Ricerche (cNR) Istituto per lo Studio degli Ecosistemi (ISE)-Sezione di Chimica del SuoloArea della RicercaVia Moruzzi 1Pisa 56124 (Italy)

A 9-month incubation experiment using composted and non-composted amendments derived from vine pruning waste and sewage sludge was carried out to study the effects of the nature and stability of organic amendments on the structural composition of organic matter (OM) in a semi-arid *** changes of soil OM,both in the whole soil and in the extractable carbon with pyrophosphate,were evaluated by pyrolysis-gas chromatography and chemical *** the end of the experiment,the soils amended with pruning waste exhibited less organic carbon loss than those receiving sewage *** non-composted residues increased the aliphatic-pyrolytic products of the OM,both in the whole soil and also in the pyrophosphate extract,with the products derived from peptides and proteins being significantly *** 9 months,in the soils amended with pruning waste the relative abundance of phenolic-pyrolytic products derived from phenolic compounds,lignin and proteins in the whole soil tended to increase more than those in the soils amended with sewage ***,the extractable OM with pyrophosphate in the soils amended with composted residues tended to have higher contents of these phenolic-pyrolytic products than that in non-composted ***,despite the stability of pruning waste,the composting of this material promoted the incorporation of phenolic compounds to the soil *** pyrolytic indices (furfural/pyrrole and aliphatic/aromatic ratios) showed the diminution of aliphatic compounds and the increase of aromatic compounds,indicating the stabilization of the OM in the amended soils after 9 *** conclusion,the changes of soil OM depend on the nature and stability of the organic amendments,with composted vine pruning waste favouring humification.

关键词： degraded soil pyrolysis-gas chromatography pyrophosphate extract sewage sludge vine pruning waste