检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1666-1680页

作者： u.K.Tarai p.S.Robi Sukhomay pal Department of Mechanical Engineering IIT GuwahatiGuwahati 781039India

A new Ni–Cr–Si–B–Fe fi ller material is prepared for transient liquid-phase(TLp)bonding of Inconel 718 superalloy by mechanical alloying *** melting temperature range of the fi ller material and its activation energy of melting are determined by diff erential scanning calorimetry *** activation energy and melting temperature of the alloy powder decrease with increasing milling *** 718 alloy was joined via TLp by using the newly developed fi ller *** eff ect of TLp bonding temperature and time on microstructural evolution and mechanical properties of the joint was *** distinct microstructural regions were observed in the bonding area:isothermal solidifi cation zone consisting of a single-phase solid solution,diff usion aff ected zone consisting of extensive diff usion-induced precipitates of metallic boride,and unaff ected base *** ultimate shear strength and microhardness of the TLp-bonded joint increase with bonding time and temperature.

关键词： Transient liquid-phase(TLp)bonding Kissinger plot Mechanical alloying Inconel 718

Ab-initio studies of the structural,electronic,optical and magnetic properties of DyMg intermetallic compound

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2017年第4期5卷 454-459页

作者： Meena Kumari u.p.Verma School of Studies in physics Jiwaji UniversityGwalior 474001India

Structural,electronic,optical and magnetic properties of DyMg intermetallic compound are calculated by using the full potential linearized augmented plane wave(Fp-LApW)method employing density functional theory(DFT).The obtained optimized equilibrium lattice constant in stable structure of DyMg(B2 phase)with spin polarized calculations is 7.107 Bohr and that without spin polarized calculations is 7.115 *** electronic band structure and density of states plots show metallic character of *** energy-dependent components of dielectric function,refractive index,extinction coefficient,absorption spectra,optical conductivity,energy loss spectra and reflectivity are reported in the energy range 0–20 *** DyMg maximum absorption is observed in the range 4–11 *** highest optical conductivity peak is observed near 0.78 eV(1589.5409 nm)and maximum energy loss occurs at 11.90 eV which corresponds to~2.8 Hz in ultraviolet *** obtained total magnetic moment shows that its value decreases with the increase in lattice parameter.

关键词： Magnesium alloy Rare-earth elements Density functional theory Band structure Optical properties Magnetic properties

Full potential study of HoMg

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2018年第2期6卷 189-196页

作者： Meena Kumari u.p.Verma School of Studies in physics Jiwaji UniversityGwalior 474011India

In this paper,HoMg is studied in two different phases i.e.B1 and *** calculated lattice constants in B1 and B2 phases are 6.39°A and 3.78°A and corresponding energies are−25,648.49 Ry and−25,648.56 Ry,*** is more stable in B2 phase(pm-3m configuration with no.221).The analysis of the obtained band structure and density of states shows metallic character of *** information about the elastic properties is also presented in this *** calculated values of Cauchy pressure,G/B and poisson ratio are−10.72,0.58 and 0.26,respectively which indicates that HoMg have brittle *** for the optical spectra such as the components of dielectric function,refractive index and other parameters of the optical properties are performed in the energy range of 0-20 *** HoMg,the main peak of absorption spectra and energy loss function is located at 7.44 eV and 11.76 eV,*** parameters such as Gruneisen parameter,Debye temperature,Specific heat *** been reported as a function of pressure and temperature.©2018 published by Elsevier *** behalf of Chongqing university.

关键词： Rare-earth magnesium alloy DFT Elastic properties Optical and thermal properties

Effect of grain structure on the mechanical properties of a Monel alloy fabricated by laser-based directed energy deposition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第33期164卷 129-139页

作者： Ze Chen Wei Fan Shubo Gao Yang Qi sastry Yagnanna Kandukuri Kun Zhou Singapore Centre for 3D printing School of Mechanical and Aerospace EngineeringNanyang Technological University50 Nanyang AvenueSingapore 639798Singapore DNV AS HøvikOslo 1363Norway

Monel K-500 is a Ni–Cu alloy widely used in the marine and offshore industry due to their superior resistance to corrosion in seawater and hence easily *** address this problem,laser-based directed energy deposition(LDED)is used to repair or refabricate these high-value worn *** optimize the mechanical properties of repaired parts,the commonly applied solution and aging is not ideal because it also changes the properties of the base ***,in situ control of the grain structures during the LDED process becomes an effective approach for high-performance *** this study,we fabricated a duplex grain structure with small grain size and low texture intensity using low laser power and scanning *** duplex microstructure consists of short columnar grains and zigzag-distributed fine equiaxed *** formation of this grain structure is dependent on both the solidification and recrystallization *** strength of this grain structure is improved to 523.5 Mpa without the sacrifice of ductility,which is instead 20%higher than that of the counterpart consisting of typical columnar grains due to the grain refinement and crack *** mechanical properties of the alloy with the duplex grain structure are even comparable to heat-treated Monel K-500 fabricated by wire arc additive *** work provides valuable insights into the in situ optimization of the microstructure and mechanical properties of LDED-fabricated parts.

关键词： Additive manufacturing Directed energy deposition Monel alloy Grain structure Mechanical properties

Synthesis and anticonvulsant activity of some potent 5,6-bis aryl 1,2,4-triazines

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang university-Science B(Biomedicine & Biotechnology) 2007年第7期8卷 526-532页

作者： MALLIKARJuNA B.p. SuRESH KuMAR G.V. sastry B.S. NAGARAJ MANOHARA K.p. Department of Medicinal Chemistry St. Johns Pharmacy College Bangalore-560040 Karnataka India Department of pharmaceutical Sciences Andhra University Visakhapatnam-530002 Andhra Pradesh India pharmacy Department M.S. University Baroda-390002 Gujarat India Department of pharmacognosy Dr. H.L.T. College of Pharmacy Bangalore-571502 Karnataka India

In the present research, a series of 5,6-bis aryl 1,2,4-triazines 5a^5f were synthesized by condensation of various benzils 4a^4f with aminoguanidine bicarbonate and were screened in vivo, for their anticonvulsant and neurotoxicity studies. Compounds 5a, 5b and 5d were found to be potent molecules of this series, when compared with the reference drugs phenytoin sodium, diazepam and lamotrigine. The structures of these compounds were established by IR, 1H NMR, 13C NMR and mass spectroscopic data.

关键词： 5,6-Bis aryl 1,2,4-triazines Synthesis Anticonvulsant activity

G-protein coupled receptors and synaptic plasticity in sleep deprivation

在线全文

学校读者我要写书评

暂无评论

World Journal of psychiatry 2021年第11期11卷 954-980页

作者： Shweta parmar Ramakrishna Tadavarty Bhagavatula R sastry Department of Anesthesiology Pharmacology and TherapeuticsThe University of British ColumbiaVancouver V6T 1Z3British ColumbiaCanada

Insufficient sleep has been correlated to many physiological and psychoneurological *** the years,our understanding of the state of sleep has transcended from an inactive period of rest to a more active state involving important cellular and molecular *** addition,during sleep,electrophysiological changes also occur in pathways in specific regions of the mammalian central nervous system(CNS).Activity mediated synaptic plasticity in the CNS can lead to long-term and sometimes permanent strengthening and/or weakening synaptic strength affecting neuronal network *** consolidation and learning that take place during sleep cycles,can be affected by changes in synaptic plasticity during sleep disturbances.G-protein coupled receptors(GpCRs),with their versatile structural and functional attributes,can regulate synaptic plasticity in CNS and hence,may be potentially affected in sleep deprived *** this review,we aim to discuss important functional changes that can take place in the CNS during sleep and sleep deprivation and how changes in GpCRs can lead to potential problems with therapeutics with pharmacological interventions.

关键词： G-protein coupled receptors Metabotropic glutamate receptors Gammaamino butyric acid-B receptor Synaptic plasticity Sleep deprivation Memory consolidation

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto Doncel-pérez Gabriel Guízar-Sahagún Israel Grijalva-Otero Hospital Nacional de parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain Medical Research unit for Neurological Diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 725-739页

作者： Benjamin R.Helmold Angela Ahrens Zachary Fitzgerald p.Hande Ozdinler Department of Neurology Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Center for Molecular Innovation and Drug Discovery Center for Developmental TherapeuticsChemistry of Life Processes InstituteNorthwestern UniversityEvanstonILUSA Mesulam Center for Cognitive Neurology and Alzheimer’s Disease Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Feinberg School of Medicine Les Turner ALS Center at Northwestern UniversityChicagoILUSA

Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.

关键词： ALS2 alsin amyotrophic lateral sclerosis hereditary spastic paraplegia neurodegenerative diseases personalized medicine precision medicine protein interactome protein-protein interactions SpAST spastin

Arbuscular mycorrhizal fungal association in Asteraceae plants growing in the arid lands of Saudi Arabia

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2015年第5期7卷 676-686页

作者： partha p DHAR Abdul A AL-QARAWI Mohammed A u MRIDHA plant production Department College of Food and Agricultural Sciences King Saud University

The present research was undertaken to explor the possibility of arbuscular mycorrhizal （AM） associa- tion with Asteraceae plants in the arid lands of Saudi Arabia （AI-Ghat, Buraydah, Thumamah and Huraymila）. AM fungal colonization in the roots, spore numbers in the rhizosphere soil, fungal species diversity and correlation between AM properties and soil properties were determined. The highest colonization was in Conyza bonariensis （65%） from AI-Ghat, Anthemis cotula （52%） from Buraydah and C. bonariensis （53%） from Thumamah. The lowest was in Vernonia schimperi （41%） from AI-Ghat, pulicaria undulata （25%） from Buraydah, Acanthospermum his- pidum （34%） from Thumamah, Asteriscus graveolens （22%） and V. schimperi （22%） from Huraymila. Vesicular and arbuscular colonization were also presented in all plant species examined. The number of spores were 112-207 in AI-Ghat, 113-133 in Buraydah, 87-148 in Thumamah and 107-158 in Huraymila. Funneliformis mosseae, Glomus etunicatum, G. fasciculatum and G aggregatum were identified. Relative frequency of AM fungal species varied widely and was irrespective of location and plant species. Diversity index varied with the rhizosphere soils of dif- ferent plant species at various locations. Soil properties varied with locations and no distinct correlations were ob- served among the soil properties, root colonization and the number of spores. The results of the present study specified the association of AM fungi in different plants of Asteraceae and its significance in the ecological func- tioning of annual plants in the punitive environments of the rangelands in Saudi Arabia.

关键词： arbuscular mycorrhizal fungi arid land Asteraceae biodiversity colonization Saudi Arabia

Optical coating and nano-structuring on plastics

在线全文

学校读者我要写书评

暂无评论

光学精密工程 2005年第4期13卷 459-464页

作者： u. Schulz p. Munzert A. Kaless N. Kaiser Fraunhofer Institut für Angewandte Optik und Feinmechnik Albert-Einstein-Str. 7 D-07745 Jena GermanyFraunhofer Institut für Angewandte Optik und Feinmechnik Albert-Einstein-Str. 7D-07745 Jena GermanyFraunhofer Institut für Angewandte Optik und Feinmechnik Albert-Einstein-Str. 7D-07745 Jena GermanyFraunhofer Institut für Angewandte Optik und Feinmechnik Albert-Einstein-Str. 7D-07745 Jena Germany

The coating of plastics for optical applications is intended to improve the mechanical durability of soft polymers and to serve an antireflection function. usually a classic four-layer antireflection system is added on top of a single-layer hard coating. With needle optimisation,an alternative coating design has been developed. plasma ion assisted deposition was used to deposit coatings upon polymers. uniform antireflection and high scratch resistance have been achieved.

关键词：光学涂覆技术纳米结构塑料光学仪器