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Co-doped BaFe_(2)As_(2) Josephson junction fabricated with a focused helium ion beam

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Chinese Physics B 2024年第4期33卷 181-186页

作者：陈紫雯张焱马平徐中堂李宇龙王越路建明马衍伟甘子钊 Applied superconductivity research Center Peking UniversityBeijing 100871China State Key Laboratory for Artificial Microstructure and Mesoscopic Physics Peking UniversityBeijing 100871China Institute of Condensed Matter Physics School of PhysicsPeking UniversityBeijing 100871China Yangtze Delta Institute of Optoelectronics Peking UniversityBeijing 100871China Key Laboratory of Applied superconductivity Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China

Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation of high-quality iron pnictide Josephson junctions is of great *** this work,we have successfully fabricated Josephson junctions from Co-doped BaFe_(2)As_(2)thin films using a direct junction fabrication technique which utilizes high energy focused helium ion beam(FHIB).The electrical transport properties were investigated for junctions fabricated with various He^(+)irradiation *** junctions show sharp superconducting transition around 24 K with a narrow transition width of 2.5 K,and a dose correlated foot-structure resistance which corresponds to the effective tuning of junction properties by He^(+)*** J_c suppression by more than two orders of magnitude can be achieved by increasing the He^(+)irradiation dose,which is advantageous for the realization of low noise ion pnictide thin film *** Shapiro steps are observed under 10 GHz microwave *** above results demonstrate the successful fabrication of high quality and controllable Co-doped BaFe_(2)As_(2)Josephson junction with high reproducibility using the FHIB technique,laying the foundation for future investigating the mechanism of iron-based superconductors,and also the further implementation in various superconducting electronic devices.

关键词： focused helium ion beam Co doped BaFe_(2)As_(2) Josephson junction

Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

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Frontiers of Computer Science 2024年第3期18卷 199-216页

作者： Antonio SANTOS-OLMO Luis Enrique SÁNCHEZ David G.ROSADO Manuel A.SERRANO Carlos BLANCO Haralambos MOURATIDIS Eduardo FERNÁNDEZ-MEDINA GSyA research group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data Science University of EssexColchester CO43SQUK Alarcos research group University of Castilla-La ManchaCiudad Real 13071Spain ISTR research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MARISMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several European and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management

Evolution of biomass particles during pelletization process

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Particuology 2024年第3期86卷 182-187页

作者： Hamid Rezaei Maryam Tajilrou Jun Sian Lee Kanages Singaraveloo Anthony Lau Shahab Sokhansanj Biomass and Bioenergy research group Department of Chemical and Biological EngineeringUniversity of British ColumbiaVancouverCanada

Pulverizing is an essential unit operation in co-firing biomass with *** are only compatible with pellet forms of fibrous biomass materials and crush them down to their original forming particle *** is why the data on the size distribution of the particles forming a biomass pellet is crucial to achieving optimum combustion *** current study determines the internal particle size distribution of pellets after wet disintegration,following Iso 17830 standard,and aims to suggest improvements to the mentioned standard based on new measured *** were carried out on white wood pellets(no bark)and brown wood pellets containing bark at four water temperatures:20,40,60,and 95℃,with or without *** particle size distribution of the pre-pelletizer wood particles was also measured and compared with particles in the formed *** water temperature of 20℃ was found to be adequate for the complete disintegration of pellets,and no mechanical stirring was *** 30% of particles in the disintegrated pellets were 0.5-1.0 *** changes the particle size distribution to smaller *** disintegrated bark pellets contained more fines than white pellets.

关键词： Wood pellets Particle sizes distribution Wet disintegration Stirring Water temperature

Short circuit analysis of a fault-tolerant current-limiting high temperature superconducting transformer in a power system in presence of distributed generations

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superconductivity 2024年第1期9卷 74-86页

作者： Alireza Sadeghi Shahin Alipour Bonab Wenjuan Song Mohammad Yazdani-Asrami Propulsion Electrification&Superconductivity GroupAutonomous Systems&Connectivity DivisionJames Watt School of EngineeringUniversity of GlasgowGlasgow G128QQUnited Kingdom

Power transformers are key elements for the safe and reliable delivery of electrical energy generated by renewable energy resources to consumers via transmission ***‐tolerant current‐limiting High Temperature Superconducting(FTCL HTS)transformers are type of superconducting transformers that tolerate fault for seconds and limit the fault current without the threat of burnout or delamination of tapes and deformation of *** this paper,the fault performance of a FTCL HTS transformer in a standard IEEE power system is *** studied transformer is a 50 MVA 132 kV/13.8 kV transformer where both windings are made up of HTS *** understudied power system consists of two microgrids with distributed *** of the power in microgrids is supplied by the upstream grid which is connected to the microgrids through the HTS *** fault scenarios have been considered in this power system,in each one of these scenarios,a fault happens in one of the *** considered fault scenarios have an approximate fault current of 18x to 23x of the rated current in the secondary *** showed that insulated windings in FTCL HTS transformers could substantially reduce the peak temperature of the HTS windings,compared to bare ***,post‐fault loading is imposed on the HTS windings,to observe their performance against the current increase after fault *** this case,for the first scenario of the faults,the FTCL HTS transformer could tolerate 192%of post‐fault overloading,while this number for the second fault scenario is 170%.Finally,the impact of post‐fault loading on the full recovery time was discussed.

关键词： Fault Energy Heat dissipation Heat transfer Insulation Recovery Time Temperature rise

Incense smoke(IS)inhalation exposure system:Physicochemical characterization,IS particle deposition and clearance in human airway using MPPD model

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Particuology 2024年第4期87卷 271-285页

作者： Vyas Kumar Hafsa Hashmi Anshita Nasreen Ghazi Ansari Jyotsna Singh Inhalation Toxicology Facility Regulatory Toxicology GroupCSR-Indian Institute of Toxicology ResearchLucknow22001UPIndi Academy of Scientific and Innovative research(AcsSIR) Ghaziabad201002UPIndia Analytical Chemistry Regulatory Toxicology GroupCSIR-Indian Institute of Toxicology ResearchLucknow226001UPIndia

Incense smoke(IS)is source of indoor air pollution and key risk for diverse human *** in-formation is available regarding controlled IS rodent inhalation exposure system and IS particulate matter(PM)deposition in human *** aimed to demonstrate stable ISPM physicochemical parameters of 10 incense products inside the customized whole body inhalation exposure chamber(without animal)connected to smoke generation unit via aerosol mixing *** analyzed for size segregated PM emission,ISPM in vitro aerodynamics(MMAD and GSD determination),fine and ultrafine particle's SEM,SEM-EDX and PAH *** real life exposure scenario by utilizing MMAD,GSD and PM concentration after Tier 1 exposure assessment as key input parameters,ISPM dosimetry in infant(3 months)and adult(21 years male and female)human airways was calculated using multiple-path particle dosimetry(MPPD 3.04)*** median aerodynamic diameter(MMAD)and geo-metric standard deviation(GSD)ranged between 0.55 and 2.10μm and 1.22 to 1.77(polydisperse)***1.0 and PM0.1 showed multiple morphology and presence of heavy and trace *** like acenaphthylene,anthracene,fluorene,naphthalene and phenanthrene were detected(0.84-143.17μg/g).MPPD results showed higher ISPM deposition in pulmonary region and lowest in trachea bronchial *** deposition in tissue was higher in lower,peripheral lung as compared to upper and central lung *** body inhalation exposure system showed stable IS atmosphere(physi-cochemical parameters)indicating the device suitability in future inhalation *** ISPM deposition fraction and clearance data showed deep lung penetrating and retention behavior with higher risk in infant followed by female and then *** modeled particle deposition and clearance data may be useful in risk assessment analysis of IS.

关键词： Inhalation Incense smoke Multiple-path particle dosimetry(MPPD) Particle deposition Particulate matter(PM) Mass median aerodynamic diameter (MMAD) Human airway

Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International Journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki Biswas Nicola J.Wagner Ofentse M.Moroeng DSI-NRF CIMERA/PPM research group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous B-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+Mn)and(Fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： Macerals Coal facies Geochemical-indices Hydrothermal Madzaringwe formation Soutpansberg Coalfield

Study on tungsten sintering temperature field based on electromagnetic simulation and computational fluid dynamics

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Tungsten 2024年第2期6卷 355-366页

作者： Lu-Yan Wang Yue-Guang Yu Jian-Xin Dong Kai-Ping Du Shan-Yu Liu Cao-Bing Li University of Science and Technology Beijing Beijing 100083China BGRIMM Technology group Beijing 100160China China Iron&Steel research Institute group Beijing 100081China

In order to study the influence of various sintering variables more intuitively and clearly,electromagnetic field analysis and computational fl uid dynamics are used to analyze the infl uence of gas flow,heating power and other process parameters on the temperature range of medium-frequency sintering in this *** results indicate that the uniformity of temperature fi eld is determined by the gas flow rate and heating *** the heating power is 50 kW,the stable temperature drops about 10 K for every 1 m^(3)·h^(−1)increase of hydrogen *** peak value of the maximum temperature diff erence on the tungsten rods gradually increases with the increase of the hydrogen flow rate,and it appears slightly *** temperature distribution of tungsten rods in furnace is similar with diff erent hydrogen flow *** the same time,the closer to the furnace wall,the higher the temperature of the tungsten *** temperature diff erence between tungsten rods mainly occurred within 1 h after the beginning of *** the heating power can improve the stable temperature,but has little eff ect on the heating *** heating power can increase the peak value of the maximum temperature diff erence on the tungsten rods,but has little eff ect on the occurrence time of the peak value of the maximum temperature diff erence on the tungsten *** the heating power will increase the temperature diff erence of a single tungsten rod,but the temperature diff erence of a single tungsten rod never exceeds 65 *** study can be used to guide the process optimization *** with numerical simulation calculation,the sintering parameters with low energy consumption and high temperature uniformity can be quickly and eff ectively found,thus improving the microstructure and properties of sintered tungsten products.

关键词： Tungsten products Sintering Hydrogen flow rate Heating power

Sludge composition and characteristics shaped microbial community and further determined process performance: A study on full-scale thermal hydrolysis-anaerobic digestion processes

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Journal of Environmental Sciences 2024年第3期137卷 96-107页

作者： Wei Liu Chenxiang Sun Wei Li Tianle Li Zhan Chen Jiawei Wang Zhengran Ren Xianghua Wen School of Environment Tsinghua UniversityBeijing 100084China Jinneng Holding group DatongShanxi 037000China research and Development Center Beijing Drainage Group Co.Ltd.Beijing 100124China Beijing Dabeinong Science and Technology group Co. Ltd.Beijing 100080China

Anaerobic digestion (AD) with thermal hydrolysis (TH) pretreatment is a promising process for excess sludge treatment,while there lacks of the knowledge from full-scale process about the impact of sludge composition and characteristics on microbial community and *** sludge physiochemical indices,microbial community and performance data of four full-scale TH-AD plants were characterized,and their relationships was *** four plants were operated under almost similar total organic loading rate (OLR)but their methanogenesis performance differentiate into two groups,namely superior group(SupG) and the inferior group (Inf G).In both groups,TH effectively solubilized particulate organic compounds,meanwhile raised the ammonia nitrogen (NH_(4)^(+)-N) and volatile fatty acid (VFA) *** with the Sup G,thermal hydrolyzed sludge of Inf G had higher level of VFAs,NH_(4)^(+)-N and total chemical oxygen demand (t COD),which showed higher inhibition effect on microbes,leading to a community with lower diversity,lower abundance of carbohydrate degrading functional guild,higher protein degrading one,and methanogens that adapted to limited substrates,and further declined the methane production ***,it was recommended that OLR alone was not sufficient for controlling the system in design and operation,the concentration of VFAs,NH_(4)^(+)-N and t COD should be equally *** higher concentration,together with the higher abundance of Defluviitoga and Proteiniphilum were recommended as indicators for inferior running *** results proposed that microbial communities played a role of bridge between environmental factors and performance,provided implications for engineering ecology and operational regulation for full-scale sludge TH-AD process.

关键词： Thermal hydrolysis Anaerobic digestion Microbial community Full-scale

Challenges and Opportunities of Sub-6 GHz Integrated Sensing and Communications for 5G-Advanced and Beyond

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Chinese Journal of Electronics 2024年第2期33卷 323-325页

作者： Yuhong HUANG China Mobile research Institute China Mobile Communications group Co. Ltd

The integrated sensing and communications(ISAC) technology has been perceived as a key feature of5G-Advanced and beyond mobile communication networks. Compared with sensing in millimeter-wave bands, sensing at sub-6 GHz band is an exceptional incentive to promote the industrialization process of ISAC due to its incomparable advantages in industrial development, especially for intelligent transportation and smart drone networks. This paper elaborates on the top challenges of sub-6 GHz ISAC technologies, as well as the potential solutions to improve the sensing capability.

关键词： Electric potential Millimeter wave technology Transportation Mobile communication Sensors Millimeter wave communication Drones