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The Influence of Method of Carburizing and Nitrocarburizing on the Microstructure and Properties of Tool Steels.

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材料热处理学报 2004年第5期25卷 386-389页

作者： Tomasz Babul Natalia Kucharieva Aleksander Nakonieczny jan senatorski Institute of Precision Mechanics Warsaw PolandBelorussian National Technical University Minsk BelarusInstitute of Precision Mechanics Warsaw PolandInstitute of Precision Mechanics Warsaw Poland

The paper presents the results of wear and metallography tests of tool steel grades: ASTM A681, Chl2M and CH12FS per COST, AMS 6437E i BS X46Crl3, all surface hardened by the Carbo process (carburizing) and by the NiCar process (nitrocarburizing). The thermo-chemical treatment was conducted in powder pack for a duration of 6 h (carburizing) and for 4 h in the case of nitrocarburizing. Factors investigated were: morphology, depth and microhardness of the cases obtained, their microstructure, as well as phase composition. Wear tests were conducted by the three cylinder-cone method. Wear velocity was 0.58 m/s, unit load was 50 MPa and 400Mpa, wear path was 3470 m. Oil SAE30 was applied at the rate of 30 drops per minute.

关键词：氮碳共渗工具钢加工动力学渗碳层厚度显微硬度磨损

Diffusion Carbide Layers, Formed on the Surface of Steel in the Vacuum Titanizing Process

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Diffusion Carbide Layers, Formed on the Surface of Steel in ...

Liver transplantation and liver resection as alternative treatments for primary hepatobiliary and secondary liver tumors: Competitors or allies?

14～(th) Congress of International Federation for Heat Treament and Surface Engineering

作者： KASPRZYCKA Ewa senatorski jan NAKONIECZNY Aleksander BABUL Tomasz Institute of Precision Mechanics Warsaw Poland Institute of Precision Mechanics Warsaw Poland Institute of Precision Mechanics Warsaw Poland Institute of Precision Mechanics Warsaw Poland

＜正＞ Diffusion layers produced on carbon steel surface in vacuum titanizing process were investigated. Studies of layers thickness, their morphology, titanium, carbon and iron concentration depth profiles in the diffusion zone of titanized layers were carried out. The effect of process parameters such as time and temperature on the kinetics of layer growth on steel surface was investigated. Tribocorrosion resistance of titanized layers was determined.

关键词： Diffusion layers thermochemical treatment vacuum titanizing wear/corrosion resistance

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 111-116页

作者： jan Lerut Institute for Experimental and Clinical Research(IREC) Universitécatholique Louvain(UCL)Avenue Hippocrate 561200 Woluwe Saint PierreBrusselsBelgium

Although Starzl designed in the 1960’s liver transplantation(LT)to treat unresectable primary and also secondary liver tumors,transplantation still occupies a(too)small place in the respective therapeutic algorithms[1].Due to the lack of(any)selection criteria,the concept of transplantation became rapidly challenged because of the prohibitively high incidence of tumor recurrence[1–3].

关键词： liver tumors Liver

Potential of molecular chaperones for treating Alzheimer’s disease

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Neural Regeneration Research 2024年第11期19卷 2343-2344页

作者： Gefei Chen jan Johansson Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Department of Cell and Molecular Biology Uppsala UniversityUppsalaSweden

Alzheimer’s disease(AD)is the most prevalent form of dementia,i.e.,progressive memory loss and profound cognitive dysfunction,resulting in a considerable societal *** the neuropathological level,the brains of AD patients exhibit amyloid-β(Aβ)plaques,neurofibrillary tangles,and neuroinflammation(Sala Frigerio and De Strooper,2016).

关键词： Alzheimer inflammation Aβ

A fiducial approach to the nonparametric deconvolution problem:The discrete case

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Science China Mathematics 2024年第11期67卷 2653-2670页

作者： Yifan Cui jan Hannig Center for Data Science Zhejiang University Department of Statistics and Operations Research University of North Carolina at Chapel Hill

Fiducial inference is applied to nonparametric g-modeling in the discrete *** propose a computationally efficient algorithm to sample from the fiducial distribution and use the generated samples to construct point estimates and confidence *** study the theoretical properties of the fiducial distribution and perform extensive simulations in various *** proposed approach gives rise to good statistical performance in terms of the mean squared error of point estimators and coverage of confidence ***,we apply the proposed fiducial method to estimate the probability of each satellite site being malignant using gastric adenocarcinoma data with 844 patients.

关键词： confidence intervals empirical Bayes fiducial inference nonparametric deconvolution

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Solid Bi_(2)O_(3)-derived nanostructured metallic bismuth with high formate selectivity for the electrocatalytic reduction of CO_(2)

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 803-811页

作者： Xiaoyan Wang Safeer jan Zhiyong Wang Xianbo Jin College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationWuhan 430072China

CO_(2) electrochemical reduction(CO_(2)ER)is an important research area for carbon ***,available catalysts for CO_(2) reduction are still characterized by limited stability and ***,metallic bismuth(Bi)has emerged as a promising catalyst for CO_(2) ***,we report the solid cathode electroreduction of commercial micronized Bi2O3as a straightforward approach for the preparation of nanostructured ***-1.1 V versus reversible hydrogen electrode in a KHCO3aqueous electrolyte,the resulting nanostructure Bi delivers a formate current density of~40 mA·cm^(-2) with a current efficiency of~86%,and the formate selectivity reaches97.6% at-0.78 *** nanosized Bi2O3as the precursor can further reduce the primary particle sizes of the resulting Bi,leading to a significantly increased formate selectivity at relatively low *** high catalytic activity of nanostructured Bi is attributable to the ultrafine and interconnected Bi nanoparticles in the nanoporous structure,which exposes abundant active sites for CO_(2) electrocatalytic reduction.

关键词： bismuth carbon dioxide electrocatalysis formate solid electroreduction

Effects of acid deposition control in China:a review based on responses of subtropical forests

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 115-126页

作者： Danni Xie Xiaodong Ge Lei Duan jan Mulder School of Land Engineering Chang’an UniversityXi’an 710064China State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesBox 5003NO-1432ÅsNorway

For many decades,acid deposition used to pose a significant regional air pollution challenge in *** substantial emission control of anthropogenically derived sulfur and nitrogen containing gasses,both sulfur and nitrogen deposition,as well as the acid rain-affected area,have significantly decreased compared to their peak ***,particularly in the humid subtropics,are sensitive to acid deposition,as evidenced by soil acidification,sulfate and nitrate leaching in stream water,and elevated soil nitrous oxide *** in the total deposition of sulfur and nitrogen,caused a significant decline in sulfate and nitrate leaching from subtropical forest and subsequently in sulfate and nitrate concentrations in stream water,although there was about a 5-year *** delay may be attributed to the desorption of accumulated sulfate and continued elevated mineralization of accumulated nitrogen *** of nitrous oxide,a potent greenhouse gas,also declined in nitrogen-saturated subtropical forest soils,as soil water nitrate concentration ***,subtropical forests in China suffering from elevated acid deposition have begun to ***,the current levels of sulfur and nitrogen deposition continue to exceed the critical loads,i.e.,the assigned threshold levels in accordance with emission control policies,in more than 10%of the country’s land area,respectively,indicating remaining risks of acidification and ***,further emission reductions are urgently needed,also because they will help achieving goals related to air quality and nitrous oxide emissions.

关键词： Acidification Critical load Nitrous oxide Surface water chemistry Recovery

Weak influence of natural vegetation in urban green spaces compared to agricultural ecosystems on House Martin populations:Insights from nationwide citizen science data in the Czech Republic

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Avian Research 2024年第2期15卷 139-146页

作者： Denisa Dvorakova jan Sipos Josef Suchomel Department of Zoology FisheriesHydrobiology and ApicultureMendel University in BrnoZemedelska 161300BrnoCzech Republic

The House Martin(Delichon urbicum)is a common farmland bird species in the European landscape,yet its population numbers are currently in ***,it is not yet sufficiently explained why this long-term decline *** fill this gap in our knowledge,we investigated how land cover composition affects the abundance of House Martins on the landscape scale by using nationwide citizen science *** a generalised linear mixed-effect model(GLMM),we evaluated 12,094 records from the Czech Republic spanning *** analysis underscores the significance of land cover type in shaping House Martin *** specifically,our results indicate that within agricultural land covers“naturally managed arable lands”exhibited significant positive effect,while forests,orchards,and vineyards were deemed less favourable for House Martin *** urban land covers,we found a clear distinction in the impact on House Martin populations,with a positive effect observed in urban infrastructure,development areas,and post-industrial sites(i.e.,UrbanAreas),while an indifferent impact was noted within urban green spaces and landscaped areas(i.e.,GreenUrban).Notably,our findings suggest that the simple spatial,age,and species structure typical of forests in Europe,and similarly,the uniform structure of parks and gardens,may be responsible for the decline in the abundance of the House *** advocate for the preservation or enhancement of urban greenery,expansion of natural vegetation in rural areas and adoption of ecological management practices in orchards and vineyards to mitigate further declines in House Martin populations.

关键词： Citizen science Habitat preferences House Martin Species distribution Urban and suburban landscape

Cut stumps vs broken stumps:Does it make any difference in the maintenance of plant and lichen biodiversity in Central European mountain forests?

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Forest Ecosystems 2024年第4期11卷 457-468页

作者： Monika Staniaszek-Kik jan Zarnowiec Damian Chmura Department of Geobotany and Plant Ecology University of Lodz90-237LodzPoland Institute of Nature Protection and Engineering University of Bielsko-BialaWillowa Str 243-309Bielsko-BiałaPoland

Fxcessive forest exploitation significantly contributes to land degradation and the creation of human-made *** are sometimes ignored in studies on the biodiversity of coarse woody *** investigated whether the type of stump,*** stumps(naturally created)and cut stumps(formed during forestry operations)had an impact on the species composition and species diversity as well as due to this fact they can be characterized by plant *** research covered 728 spruce stumps(287 broken and 441 cut stumps)that were inhabited by lichens,liverworts,mosses and vascular plants in mountain forest belt(Karkonosze Mts.,Poland).The following types of microhabitats were included in the research:the upper surface and the lateral surface of a stump with both bark and *** are statistically significant compositional differences between the two types of stumps,which was demonstrated by ordination analyses and indicator species *** to the generalized linear models,the probability of occurrence increases in cut stumps in case of liverworts and vascular plants and also along the decomposition *** generalized linear mixed-effects model showed that there was a higher species richness of liverworts,mosses and vascular plants on the cut stumps and less drier but the reverse situation was in *** generalized additive models for their cover showed similar *** all of the taxonomic groups were affected by altitude both in terms of species composition and total cover on the *** concluded that cut stumps are an important type of deadwood for biodiversity and provide a convenient habitat,especially for many lichens and bryophytes.

关键词： Coarse woody debris Spruce stumps Epixylic flora Plant indicators