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Passive electrochemical hydrogen recombiner for hydrogen safety systems:prospects

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Nuclear Science and Techniques 2023年第6期34卷 215-224页

作者： A.V.Avdeenkov d.g.Bessarabov d.g.Zaryugin All Russian Research Institute for Nuclear Power Plants Operation JSC 25 Ferganskaya Str.MoscowRussia109507 HySA Center Faculty of EngineeringNorth-West UniversityPotchefstroom2520South Africa State Atomic Energy Corporation Rosatom 24 Bolshaya Ordynka Str.MoscowRussia119017

This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design accidents.An experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(MEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were recorded.The simplest MEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.

关键词： Recombiner Catalytic ignition Hydrogen explosion safety Hydrogen fuel cell Membrane electrode assembly

衬底对飞秒激光脉冲照射后薄金属目标光热响应的影响

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Journal of Central South University 2022年第10期29卷 3410-3421页

作者： TSIBIdIS g d STRATAKIS E Institute of Electronic Structure and Laser(IESL) Foundation for Research and Technology(FORTH)N.Plastira 100Vassilika Vouton70013 HeraklionCreteGreece department of Materials Science and Technology University of Crete70013 HeraklionCreteGreece department of Physics University of Crete70013 HeraklionCreteGreece

飞秒脉冲激光器由于其在微、纳米尺度上图案制造精确的能力,在过去的几十年里得到了广泛的应用。对于高效材料加工,一个关键问题是确定在实验装置中使用的激光参数,而在已进行的系统研究中,主要是强调独立的单个参数的影响,很少关注辐... 详细信息

飞秒脉冲激光器由于其在微、纳米尺度上图案制造精确的能力,在过去的几十年里得到了广泛的应用。对于高效材料加工,一个关键问题是确定在实验装置中使用的激光参数,而在已进行的系统研究中,主要是强调独立的单个参数的影响,很少关注辐照的固体基底材料的作用。因此,本研究强调了衬底对不同厚度薄膜的影响,结果表明,衬底的光学和热物理性质都对辐照薄膜上的热指纹有影响,在较小的薄膜尺寸下影响较大。选择了两种代表性材料硅和熔融硅作为不同光学和热物理形态薄膜(金和镍)的典型衬底,并对辐照的固体热响应和损伤阈值进行评估,为基于激光的制备装置和工艺的设计提供指导。

关键词：飞秒激光脉冲超快动力学光激发双温度模型

Behavioral aspects and the transmission of Monkeypox:A novel approach to determine the probability of transmission for sexually transmissible diseases

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Infectious disease Modelling 2023年第3期8卷 842-854页

作者： g.d.Fernandes Victor Maldonado Mechanical Engineering department Texas Tech UniversityUSA

Motivated by the 2022 worldwide Monkeypox(MPox)outbreak,a compartmental model is proposed to predict the evolution of the disease.Numerous models have been proposed for infectious diseases so far,although the number of variables makes it difficult to establish causation relations between individual factors and transmission rates.In order to evaluate the reaction of susceptible people to avoid infection during the outbreak,the rate of transmission is modeled through a unique phenomenological probabilistic approach,allowing the expression of the rate of generation of new cases in terms of two charac-teristics of the susceptible group:the frequency of sexual encounters and the probability of transmission given that there is a sexual encounter.Transmission rates are obtained and compared for the U.S.and several other countries.Results show reductions of up to 71%in the transmissibility parameter,which may be combined with variations in the frequency of sexual encounters(obtained through behavioral research)to determine the changes in the probability of transmission during an outbreak in a much more convenient way than current alternatives.This framework presents a valuable tool to health authorities in the understanding of future sexually transmissible disease outbreaks.

关键词： approach convenient determine

Petrographical and mineral chemistry evidence to delineate the source/sources of the Central Indian Ocean Basin pumices

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Acta Oceanologica Sinica 2023年第5期42卷 102-116页

作者： Niyati g.Kalangutkar Sridhar d.Iyer School of Earth Ocean and Atmospheric SciencesGoa UniversityTaleigao PlateauGoa 403206India Formerly with CSIR-National Institute of Oceanography Dona PaulaGoa 403004India

We present data pertaining to mineral assemblages and composition of the Central Indian Ocean Basin(CIOB)pumices.Eight groups of pumices were identified considering the presence of phenocrysts of plagioclase,clinopyroxene,orthopyroxene,hornblende and biotite together with the occurrence of quartz and glass.Pigeonite,fayalite and ulvospinelare reported for the first time from these pumices.In the eight groups,the modal percentage of the constituents are phenocrysts 3%to 19%(avg 9.6%),silicic glass 33%to 54%(avg 43%)and the rest is vesicles.Based on the above factors we have identified the possible sources of the CIOB pumices.The mineral compositions of plagioclase,pyroxenes,and biotite of the CIOB pumices were compared with those of Krakatau and Toba.Most of the plagioclase and pyroxene compositions resemble the Haranggoal dacite Tuff of Toba and Krakatau.Considering the mineral assemblages and compositions,there are pumices which do not correlate to any of the above eruptions and are probably from yet unidentified source/sources.These sources could either be from nearby terrestrial volcanoes or intraplate seamounts present in the CIOB.In a global context,it is viable that petrological characteristics could be used as initial criteria to determine the source of pumices that occur at abyssal depths in the world ocean.

关键词： CIOB pumice petrography mineral chemistry Indonesian Arc intraplate volcanism

Modulational Instability of Optical Vortices in Engineered Saturable Media

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Engineering 2022年第10期17卷 31-43页

作者： d.g.Pires N.M.Litchinitser department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA

Propagation of light beams in turbid media such as underwater environments,fog,clouds,or biological tissues finds increasingly important applications in science and technology,including bio-imaging,underwater communication,and free-space communication technologies.While many of these applications traditionally relied on conventional,linearly polarized gaussian beams,light possesses many degrees of freedom that are still largely unexplored,such as spin angular momentum(SAM)and orbital angular momentum(OAM).Here,we present nonlinear light-matter interactions of such complex light beams with"rotational"degrees of freedom in engineered nonlinear colloidal media.By making use of both variational and perturbative approach,we consider non-cylindrical optical vortices,elliptical optical vortices,and higher-order Bessel beams integrated in time(HOBBIT)to predict the dynamics and stability of the evolution of these beams.These results may find applications in many scenarios involving light transmission in strongly scattering environments.

关键词： Optical vortex Orbital angular momentum Modulation instability Turbid media

Novel approach for modified forms of Camassa–Holm and degasperis–Procesi equations using fractional operator

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Communications in Theoretical Physics 2020年第10期72卷 12-18页

作者： P Veeresha d g Prakasha department of Mathematics Karnatak UniversityDharwad-580003KarnatakaIndia department of Mathematics Faculty of ScienceDavangere UniversityShivagangothriDavangere 577007KarnatakaIndia

In the present study,we consider the q-homotopy analysis transform method to find the solution for modified Camassa–Holm and degasperis–Procesi equations using the Caputo fractional operator.Both the considered equations are nonlinear and exemplify shallow water behaviour.We present the solution procedure for the fractional operator and the projected solution procedure gives a rapidly convergent series solution.The solution behaviour is demonstrated as compared with the exact solution and the response is plotted in 2d plots for a diverse fractional-order achieved by the Caputo derivative to show the importance of incorporating the generalised concept.The accuracy of the considered method is illustrated with available results in the numerical simulation.The convergence providence of the achieved solution is established in?-curves for a distinct arbitrary order.Moreover,some simulations and the important nature of the considered model,with the help of obtained results,shows the efficiency of the considered fractional operator and algorithm,while examining the nonlinear equations describing real-world problems.

关键词： Laplace transform Camassa–Holm equation q-homotopy analysis method degasperis–Procesi equation fractional derivative

Landslide inventory validation and susceptibility mapping in the gerecse Hills, Hungary

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geo-Spatial Information Science 2021年第3期24卷 498-508页

作者： dávid gerzsenyi gáspár Albert department of Cartography and geoinformatics Eötvös Loránd UniversityBudapestHungary

Landslides pose a threat to property both in the populated and cultivated areas of the gerecse Hills (Hungary). The currently available landslide inventory database holds the records from many sites in the area, but the database is out-of-date. Here we address the problem of revising the National Landslides Cadastre landslide inventory database by creating a landslide suscept-ibility map with a multivariate model based on likelihood ratio functions. The model is applied to the TandEM-X dEM (0.4″ res.), the current landslide inventory of the area, and data acquired from geological maps. By comparing the distributions of four variables in the landslide and non-landslide area with grid computation methods, the model yields landslide susceptibility estimates for the study area. The estimations show to what extent a certain area is similar to the sample areas, therefore, its likelihood to be affected by landslides in the future. The accuracy of the model predictions was checked in the field and compared to the results of our previous study using the SRTM-1 dEM for a similar analysis. The model gave accurate estimates when certain correction measures were applied to the input datasets. The limitations of the model, the input datasets, and the suggested correction measures are also discussed.

关键词： Landslide susceptibility landslide inventory TandEM-X gerecse Hills landslides geomorphometry

现有防疫通风措施及基于先进气流组织的源头控制技术应用

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湖南大学学报（自然科学版） 2022年第5期49卷 203-214页

作者：艾正涛叶金军 MELIKOV A K MARKOV d g 湖南大学土木工程学院湖南长沙410082 丹麦技术大学国际室内环境与能源研究中心哥本哈根DK-2800 索菲亚技术大学人类舒适、能源和环境设计研究中心索菲亚BG-1000

新冠疫情暴发后,如何应对呼吸道传染病的传播这一难题再次摆在了人们面前.通风是最重要的工程防疫措施,ASHRAE、REHVA、SHASE以及中国的相关机构、学会就如何利用暖通空调系统有效防控COVId-19的传播相继出台了指导性文件.总结和分析系... 详细信息

新冠疫情暴发后,如何应对呼吸道传染病的传播这一难题再次摆在了人们面前.通风是最重要的工程防疫措施,ASHRAE、REHVA、SHASE以及中国的相关机构、学会就如何利用暖通空调系统有效防控COVId-19的传播相继出台了指导性文件.总结和分析系列指导性文件中有关通风量和气流组织方面的内容,发现现有工程防疫措施尚存在诸多需改进之处.传统的全空间通风在疫情期间表现出通风量不足、对近距离短期暴露事件效率低下、能耗高等缺陷,而基于先进气流组织的源头控制技术具有控制效率高、个性化可调、响应快速且节能潜力大等优势,恰好可弥补全空间通风的不足.在此基础上,系统地总结了基于先进气流组织的源头控制措施在呼吸道传染病传播控制方面的技术类型,并考虑到后疫情时代通风系统设计面临以“平疫结合”为导向的发展趋势,探讨了在“平疫结合”中应用源头控制技术的优势,以及在一些高风险场景应用源头控制从而实现“平疫结合”的技术路线,并分析了为落实“平疫结合”设计理念所需进一步探索的技术方向.所做探索预期为后续指南的编撰提供参考,为未来防疫通风设计带来新思路和新启示.

关键词：新冠疫情源头控制先进气流组织平疫结合交叉感染

Cryptotanshinone ameliorates cladribine-induced cognitive impairment in rats

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Asian Pacific Journal of Tropical Biomedicine 2023年第7期13卷 296-305页

作者： Khadga Raj Aran g.d.gupta Shamsher Singh Neuroscience division Department of PharmacologyISF College of Pharmacy(An Autonomous College)MogaPunjabIndia-142001 I.K.gujral Punjab Technical University JalandharIndia department of Pharmaceutics ISF College of PharmacyMogaPunjabIndia-142001

Objective:To evaluate the neuroprotective effect of cryptotanshinone against cladribine-induced cognitive impairment in rats.Methods:Rats were administered with cladribine(1 mg/kg,p.o.)and cryptotanshinone(10 and 20 mg/kg,i.p.)for four weeks.Behavioral tests such as Morris water maze and elevated plus maze were conducted to check memory impairment caused by cladribine.On day 29,all rats were sacrificed,and the brains were separated for estimation of neuroinflammatory factors,biochemical parameters,neurotransmitters,Aβ(1-42),blood-brain barrier permeability,nuclear factor erythroid 2-related factor 2(Nrf2),and brain-derived neurotrophic factor(BdNF).Results:Treatment with cryptotanshinone dose-dependently enhanced spatial memory,improved the levels of neurotransmitter and antioxidant enzymes,and suppressed proinflammatory cytokine release.Cryptotanshinone also decreased Aβ(1-42)accumulation and increased the levels of Nrf2 and BdNF in the hippocampus.Additionally,the histopathological results showed that cryptotanshinone reduced cladribine-induced neuronal death in the hippocampus.Conclusions:Cryptotanshinone exhibits a promising neuroprotective effect against cladribine-induced cognitive impairment in preclinical studies,and may be a potential phytochemical for the treatment and management of cognitive impairment.

关键词： Alzheimer's disease Cladribine Cryptotanshinone Neurotransmitters Neuroprotective Proinflammatory cytokines Cognitive deficit