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Investigation of 50 Hz Pulsed DC Nitrogen Plasma with Active Screen Cage by Trace Rare Gas Optical Emission Spectroscopy

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Plasma Science and Technology 2014年第4期16卷 324-328页

作者： A.SAEED A.W.KHAN M.SHAfIQ f.jan M.ABRAR M.ZAKA-UL-ISLAM M.ZAKAULLAH Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Plasmant Department of Chemistry Univesity of Antwerp campus DriEkin

Optical emission spectroscopy is used to investigate the nitrogen-hydrogen with trace rare gas （4% Ar） plasma generated by 50 Hz pulsed DC discharges. The filling pressure varies from 1 mbar to 5 mbar and the current density ranges from 1 mA-cm-2 to 4 ***-2. The hydrogen concentration in the mixture plasma varies from 0% to 80%, with the objective of identifying the optimum pressure, current density and hydrogen concentration for active species （[N] and IN2]） generation. It is observed that in an N2-H2 gas mixture, the concentration of N atom density decreases with filling pressure and increases with current density, with other parameters of the discharge kept unchanged. The maximum concentrations of active species were found for 40% H2 in the mixture at 3 mbar pressure and current density of 4 ***-2.

关键词： TRG-OES DC glow discharge reactive species

Optimization Study of Pulsed DC Nitrogen-Hydrogen Plasma in the Presence of an Active Screen Cage

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Plasma Science and Technology 2014年第5期16卷 460-464页

作者： A.SAEED A.W.KHAN f.jan H.U.SHAH M.ABRAR M.ZAKA-UI-ISLAM M.KHALID M.ZAKAULLAH National Centre for Physics Quaid-i-Azam University Campus Islamabad Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Department of Physics Faculty of ScienceUniversity of Jazan

A glow discharge plasma nitriding reactor in the presence of an active screen cage is optimized in terms of current density,filling pressure and hydrogen concentrations using optical emission spectroscopy（OES）.The samples of AISI 304 are nitrided for different treatment times under optimum *** treated samples were analyzed by X-ray diffraction（XRD） to explore the changes induced in the crystallographic *** XRD pattern confirmed the formation of iron and chromium nitrides arising from incorporation of nitrogen as an interstitial solid solution in the iron lattice.A Vickers microhardness tester was used to evaluate the surface hardness as a function of treatment time（h）.The results showed clear evidence of improved surface hardness and a substantial amount of decrease in the treatment time compared with the previous work.

关键词： optical diagnostics plasma nitriding austenitic stainless steel

Catalysis on Interface of Nano-oxide and Nano-zeolite

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复旦学报（自然科学版） 2007年第5期46卷 867-页

作者： K.Ito f.jan S.Asaoka faculty of Environmental Engineering the University of Kitakyushu

1 Results The catalysts which can efficiently hydro-reform higher n-paraffin to lower isoparaffins for environmentally-friendly gasoline were studied. The catalysts were examined by the conversion of n-hexadecane, n-C16H34 to i-C6H14—*** tri-modally nano-porous catalysts composed of (Ni-Mo)/[γ-Al2O3], nano-oxide, and nano-crystalline zeolite had some active and selective performance because of the interface between nano-oxide and nano-zeolite. The catalyst composed of nano-crystalline MfI or BE...

关键词： nano-pore nano-oxide nano-zeolite nano-interface

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

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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

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