检索结果-南通市图书馆

In situ TEm investigation of electron irradiation and aging-induced high-density nanoprecipitates in an mg-10Gd-3Y-1Zn-0.5Zr alloy

维普期刊数据库评论

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 2024年第5期12卷 1841-1853页

作者： m.lv H.l.Ge Q.Q.Jin X.H.Shao Y.T.Zhou B.Zhang X.l.ma Shenyang National laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： mg alloy Electron beam irradiation Hardening Precipitates In-situ TEm

Greatly enhanced corrosion/wear resistances of epoxy coating for mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

在线全文

学校读者我要写书评

暂无评论

Journal of magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.li J.H.Chu m.m.li D.N.Zou l.B.Tong School of metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key laboratory of Advanced Design and manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of mg alloys.

关键词： mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

Evaluation of mechanical Properties and Surface Quality of Wood from Bosnia and Herzegovina Exposed to Outdoor Conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Renewable materials 2024年第8期12卷 1417-1431页

作者： Hasanagić R. Šljivo U. Fathi l. Gautam P. Bahmani m. Humar m. Department of Wood Science and Technology Faculty of Technical Engineering University of Bihać Bihać 77000 Bosnia and Herzegovina Department of Wood and Furniture Industry Engineering Faculty of Resources and Earth Science Shahrekord University Shahrekord 64165478 Iran Department of Botany Institute of Science Banaras Hindu University Uttar Pradesh Varanasi 221005 India Biotechnical Faculty Department of Wood Science University of Ljubljana Ljubljana 1501 Slovenia

This study investigated the mechanical properties of beech (Fagus sylvatica l.) and fir (Abies alba) wood from Bosnia and Herzegovina under outdoor exposure. Samples were exposed for 3-month exposure to assess bending strength, color changes, and surface quality. Results showed outdoor exposure negatively affected mechanical properties, particularly in samples with extended finger joints, causing significant surface cracks in uncoated sam-ples. Beech wood exhibited notable color changes under exposure, with approximately 50% darkening without coating compared to 25% under covered conditions. Coated samples displayed minimal color changes, affirming the efficacy of surface treatment. Fir wood exhibited a roughness of 8.264 μm, while beechwood average roughness increased from 6.767 to 13.916 μm after exposure, with micro-pore development affecting water perfor-mance. microscopic analysis identified prevalent fungal colonies, including Penicillium, Aureobasidium, Sclerophoma, and Chaetomium, underscoring their role in organic matter decomposition. This study highlights the importance of wood exposure and treatment selection for various applications. © 2024 The Authors.

关键词： cracks mechanical properties outdoor conditions wood species

langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application

维普期刊数据库评论

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 Wuhan University of Technology(materials Science) 2024年第5期39卷 1311-1318页

作者： WONG Yeong Yi F l Supian A Radzwan m musa N F N Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the langmuir method and first-principle density functional theory(DFT).Using the langmuir-Schaefer(lS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the lS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory langmuir-Schaefer PABA sensor

The secondary injury cascade after spinal cord injury: an analysis of local cytokine/chemokine regulation

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第6期19卷 1308-1317页

作者： Daniel J.Hellenbrand Charles m.Quinn Zachariah J.Piper Ryan T.Elder Raveena R.mishra Taylor l.marti Phoebe m.Omuro Rylie m.Roddick Jae Sung lee William l.murphy Amgad S.Hanna Department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public Health Department of Biomedical Engineering University of Wisconsin-Madison Department of Orthopedics and Rehabilitation University of Wisconsin-Madison Department of materials Science and Engineering University of Wisconsin-Madison Forward BIO Institute University of Wisconsin-Madison

After spinal cord injury, there is an extensive infiltration of immune cells, which exacerbates the injury and leads to further neural degeneration. Therefore, a major aim of current research involves targeting the immune response as a treatment for spinal cord injury. Although much research has been performed analyzing the complex inflammatory process following spinal cord injury, there remain major discrepancies within previous literature regarding the timeline of local cytokine regulation. The objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury, identify sexual dimorphisms in terms of cytokine levels, and determine local cytokines that significantly change based on the severity of spinal cord injury. Rats were inflicted with either a mild contusion, moderate contusion, severe contusion, or complete transection, 7 mm of spinal cord centered on the injury was harvested at varying times post-injury, and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex assay. Results demonstrated pro-inflammatory cytokines including tumor necrosis factor α, interleukin-1β, and interleukin-6 were all upregulated after spinal cord injury, but returned to uninjured levels within approximately 24 hours post-injury, while chemokines including monocyte chemoattractant protein-1 remained upregulated for days post-injury. In contrast, several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days post-injury. After spinal cord injury, tissue inhibitor of metalloproteinase-1, which specifically affects astrocytes involved in glial scar development, increased more than all other cytokines tested, reaching 26.9-fold higher than uninjured rats. After a mild injury, 11 cytokines demonstrated sexual dimorphisms; however, after a severe contusion only leptin levels were different between female and male rats. In conclus

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord injury

Effect of Turbidity on Semi-Automatic Analysis of Copepod Size and Abundance Distribution in the Water Column

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Advances in Bioscience and Biotechnology 2024年第6期15卷 380-395页

作者： Thiago da Silva matos Carolina Siqueira dos Reis laura de andrade moura márcio Abreu Ricardo Coutinho lohengrin Fernandes IEAPm/UFF marine Biotechnology Post-Graduate Program Arraial do Cabo Brazil Instituto de Estudos do mar Almirante Paulo moreira Arraial do Cabo Brazil

Automated image systems to characterize aquatic organisms improve research and enable fast response to environmental risk situations. In November 2015, a dam in mariana City-mG (Brazil) collapsed and led to the disposal of mud tailings from the mining process to the Doce River. The accident resulted in several casualties and incalculable damage to surrounding communities and the environment. The mud increased water turbidity, an essential condition to the functioning of the image analysis systems, and directly affected the characterization of the organisms, making it impossible to distinguish copepods in the mud, due to the blurred outline. To get a quick response evaluating environmental situations, this work aimed to develop and test different algorithms characterizing and classifying copepods by their size (length and area) using in situ images acquired by the lightframe On-Sight Keyspecies Investigation device. Field tests were carried out under different turbidity levels throughout the gradient observed in the coastal zone adjacent to the Doce River. The best algorithm reduced nearly 50% of the noise in some images when compared with manual treatment and led to 96% accuracy in measurement and counting. Semi-automated devices that perform post-processing corrections are suitable for fast environmental evaluation under high turbidity scenarios.

关键词： Imaging Zooplankton Doce River lOKI Copepod

Post-fire recovery of Puya raimondii, vegetation and birds in the puna of Huascarán National Park, Perú

维普期刊数据库评论

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 mountain Science 2024年第1期21卷 20-32页

作者： mery l.SUNI Giovana P.VADIllO César ARANA Enoc JARA-PENA letty SAlINAS m.Estela PONCE Paul m.RAmSAY Plant Physiology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Natural History museum Universidad Nacional Mayor de San MarcosLima 15072Peru Applied Phytology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Statistics Faculty of Mathematical SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Chemical and Biological Sciences Universidad de las Américas PueblaSan Andrés Cholula CP Cholula CP 72810Mexico

A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, Puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of Puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.

关键词： Burning Plant biomass Trophic guilds Andes Giant rosette plants

A Theoretically Grounded Question Answering Data Set for Evaluating machine Common Sense

在线全文

学校读者我要写书评

暂无评论

Data Intelligence 2024年第1期6卷 1-28页

作者： Henrique Santos Ke Shen Alice m.mulvehill mayank Kejriwal Deborah l.mcGuinness Rensselaer Polytechnic Institute Troy NY Information Sciences Institute Marina del Rey CA

Achieving machine common sense has been a longstanding problem within Artificial *** far,benchmark data sets that are grounded in a theory of common sense and can be used to conduct rigorous,semantic evaluations of common sense reasoning(CSR)systems have been *** expectation of the AI community is that neuro-symbolic reasoners can help bridge this gap towards more dependable systems with common *** propose a novel benchmark,called Theoretically Grounded common sense Reasoning(TG-CSR),modeled as a set of question answering instances,with each instance grounded in a semantic category of common sense,such as space,time,and *** benchmark is few-shot i.e.,only a few training and validation examples are provided in the public release to avoid the possibility of *** from recent evaluations suggest that TG-CSR is challenging even for state-of-the-art statistical *** to its semantic rigor,this benchmark can be used to evaluate the common sense reasoning capabilities of neuro-symbolic systems.

关键词： reasoning Intelligence instance

Cr-induced fusion reactions to synthesize superheavy elements

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.madhu H.C.manjunatha N.Sowmya B.m.Rajesh l.Seenappa R.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)Cr+^(243)Am,23.2 fb at 236 meV for ^(54)Cr+^(247)Cm,95.6 fb at 240 meV for ^(53)Cr+248Bk,and 1.33 fb at 242 meV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections