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Prediction of intrusive gas pores caused by resin burning in sand core for iron castings

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China Foundry 2025年第1期22卷 23-32页

作者： Ji-wu Wang Xiao-long Wang Yu-cheng sun Yu-hang huang Xiu-ming Chen Xiong-zhi wu Na Li Jin-wu kang Tao Jing Tian-you huang Hai-liang Yu School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Weichai Power Co. Ltd.Weifang 261061ShandongChina School of Mechanical Engineering Central South UniversityChangsha 41000China School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for *** occurs due to the intrusion of gases generated during the resin burning of the sand core into castings during the casting ***,a gas generation and flow constitution model was established,in which the gas generation rate is a function of temperature and time,and the flow of gas is controlled by the gas release,conservation,and Darcy's *** heat transfer and gas flow during casting process was numerically *** dangerous point of cores is firstly identified by a virtual heat transfer method based on the similarity between heat transfer and gas flow in the sand *** gas pores in castings are predicted by the gas pressure,the viscosity and state of the melt for these dangerous *** distinct sand core structures were designed and used for the production of iron castings,and the simulated gas pore results were validated by the obtained castings.

关键词： gas pore numerical simulation iron casting sand core resin

Potassium-modified carbon nitride photocatalyzed-aminoacylation of N–sulfonyl ketimines

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Chinese Chemical Letters 2025年第2期36卷 406-411页

作者： Cailing wu Shaojie wu Qifei huang Kai sun Xianqiang huang Jianji Wang Bing Yu Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and ReactionsMinistry of Education School of Chemistry and Chemical Engineering Henan Normal University College of Chemistry Zhengzhou University School of Chemistry & Chemical Engineering Liaocheng University

The development of innovative and sustainable catalytic strategies for organic synthesis is a pivotal aspect of advancing material science and chemical *** research presents a new catalytic method for the aminoacylation of N–sulfonyl ketimines by utilizing a potassium-doped graphite-like carbon nitride （g-C3N4） *** method not only enhances the catalytic efficiency and broadens the light absorption spectrum of g-C3N4but also significantly reduces the recombination rate of electronhole pairs,thereby increasing the reaction yield and ***,our approach facilitates the synthesis of aminoacylated N-heterocycles,expanding the applicability of potassium-modified g-C3N4in photocatalytic organic synthesis.A notable accomplishment of this study is the unprecedented generation of carbamoyl radicals via heterogeneous photocatalysis,which can be easily recycled after *** advancement highlights the capability of potassium-doped g-C3N4（namely K-CN） as an advanced heterogeneous photocatalyst for the formation of complex organic compounds.

关键词： Amides Aminoacylation K+-modified carbon nitride Oxamic acids Photocatalysis

In situ measurement of environmental γ radiation dose rates of key nuclides for large radioactive surface sources

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Nuclear Science and Techniques 2025年第1期36卷 69-79页

作者： Ze-Qian wu Jian sun Wei-Qi huang Bai-Rong Wang Jin-Xing Cheng Jiang-feng wu Yong-Hong Wang Biao Yuan Sheng Qi Kun Shan Institute of NBC Defence Beijing 102205China Beijing New-High Technology Academy Beijing 100094China

To monitor nuclear and radiation emergencies,it is crucial to obtain accurate in situ measurements of the environmentalγ radiation dose rate from key radionuclides,particularly for large radioactive surface *** methods currently used for measuring dose rates are inadequate for obtaining the dose rates of key radionuclides and have large angular response errors when monitoring surface *** address this practical problem,this study proposes three methods for measuring the dose rate:the weighted peak total ratio,mean value regression,and numerical integration *** methods are based on energy-spectrum measurement data,and they were theoretically derived and numerically ***,a 1-m-long hexagonal radioactive surface source was integrated into a larger surface *** situ measurement experiments were conducted on a large radioactive surface source using a dose-rate meter and a portable HPGespectrometer to analyze the errors of the three aforementioned methods and verify their validity.

关键词： Environmentalγradiation dose rate HPGespectrometer Key radionuclides Radioactive surface source

Last digit tendency:Lucky numbers and psychological rounding in mobile transactions

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Fundamental Research 2025年第1期5卷 370-378页

作者： Hai Wang Tian Lu Yingjie Zhang Yue wu Yiheng sun Jingran dong Wen huang School of Computing and Information Systems Singapore Management UniversitySingapore 178902Singapore W.P.Carey School of Business Arizona State UniversityTempeAZ 85287USA Guanghua School of Management Peking UniversityBeijing 100871China Tencent Weixin Group Shenzhen 518054China

The distribution of digits in numbers obtained from different sources reveals interesting *** well-known Benford’s law states that the first digits in many real-life numerical data sets have an asymmetric,logarithmic distribution in which small digits are more common;this asymmetry diminishes for subsequent digits,and the last digit tends to be uniformly *** this paper,we investigate the digit distribution of numbers in a large mobile transaction data set with 835 million mobile transactions and payments made by approximately 460,000 users in more than 300 *** the first digits of the numbers in these mobile transactions follow Benford’s law,the last digit has a strong tendency to be a lucky number or be influenced by psychological *** lucky number tendency is more significant in transactions that are more strongly connected to social interactions,such as money sent as gifts or as“red envelopes”(a traditional method of gift-giving during Chinese holidays),and in transactions by individuals with potentially greater emotional needs,such as during COVID-19 outbreaks and natural *** psychological rounding tendency is more common in online e-commerce payments,in-store purchases,and money transfers between *** findings are key for understanding the last digit tendency and its psychological and emotional mechanisms,which could be used as an indicator of public sentiment or in methods of detecting fraudulent business activity.

关键词： Last digit Lucky number Psychological rounding Mobile transaction Difference-in-differences

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： feng Zhang Chenyang Zhang Linlin wu Wei sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Effect of h-BN rods on high-temperature properties of alumina-carbon refractory

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Journal of Iron and Steel Research International 2025年第1期32卷 115-128页

作者： Ya-ge Li Shuai-bing wu feng Liang Zhong huang Tu Long Long dong Jun-yi Lv Hong-juan Duan Biao Wen Yong Liu Hai-jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Sinosteel Luoyang Institute of Refractories Research Co. Ltd.Luoyang471039HenanChina

h-BN rods modified low-carbon alumina-carbon(Al_(2)O_(3)-C)refractories were prepared,and the effect of h-BN rod addition on the high-temperature properties was investigated and compared with commercial h-BN flake,carbon black,and carbon nanotubes *** results demonstrated that Al_(2)O_(3)-C refractories containing h-BN rods exhibited optimal high-temperature service performances,including 25%higher hot modulus of rupture,21.3%higher thermal shock strength residual ratio,20.9%lower in oxidation and 44.3%less in slag corrosion,compared to the counterpart specimens without ***,benefiting from the synergistic enhancement of the rod-like h-BN and in-situ generated SiC whiskers,the high-temperature service performances of h-BN rods containing specimens outperformed counterpart specimens containing commercial h-BN flake,carbon black,and carbon nanotubes,respectively.

关键词： Al_(2)O_(3)-C refractory h-BN rod Microstructure High-temperature service performance

Compositions and Distributions of Secondary Organic Aerosols and Their Tracers over the Pearl River Estuary Region Influenced by Continental and Marine Air Masses

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Advances in Atmospheric Sciences 2025年第4期42卷 682-696页

作者： Zhenhao ling Junlin huang Liqing wu Yee Jun THAM Guizhen FANG Bing wu Lili MING xuemei WANG Xiang DING School of Atmospheric Sciences Sun Yat-sen UniversityKey Laboratory of Tropical Atmosphere-Ocean SystemMinistry of Educationand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiChina College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiangChina School of Marine Sciences Sun Yat-sen UniversityZhuhaiChina Technical Center of Gongbei Customs District of China ZhuhaiChina College of Environment and Climate Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental QualityJinan UniversityGuangzhouChina Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhouChina

The compositions and distributions of monoterpenes,isoprene,aromatics and sesquiterpene SOA tracers(SOAM,SOAI,SOAA and SOAS,respectively)at an island site(Da Wan Shan Island,DWS)were investigated in the context of the influence of continental and marine air masses over the Pearl River Estuary(PRE)region in winter *** sum concentration of SOA tracers was 6.2–132.8 ng m^(−3),with SOAM and SOAI as the main components in both continental(scenarios A1 and A2)and marine air masses(scenario A3),as well as their combination(scenario A4).The highest and lowest levels of SOAM were observed in A1 and A3,respectively,which were mainly related to the variations in meteorological conditions,precursor concentrations,and the degree of photochemical *** MBTCA/HGA(3-methyl-1,2,3-butanetricarboxylic acid/3-hydroxyglutaric acid)ratios suggested a less significant contribution fromα-pinene to *** variations of SOAI in the different scenarios were associated with differences in relative humidity,particle acidity,and isoprene/NOx *** respective highest and lowest concentrations of aromatics SOA tracers in A1 and A3 revealed the influence of anthropogenic precursors from upwind continental areas,which was confirmed by the correlation among biogenic and anthropogenic *** results of the tracer-based-method suggested dominant contributions of SOAs from aromatics and monoterpenes,with the highest concentrations in A1.A WRF-Chem simulation revealed that the SOAs from the above precursors only contributed 12%–25%to the total SOA at DWS,while the spatial distributions of SOAs further highlighted that the abundance of SOAs over the PRE region in winter is highly associated with air masses transported from upwind continental areas.

关键词： secondary organic aerosols tracers continental and marine air masses Pearl River Estuary region

Systematic analysis of innate immune-related genes in the silkworm:Application to antiviral research

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Insect Science 2025年第1期32卷 151-171页

作者： Junming Xia Ruoxuan Peng Shigang Fei Mian Muhammad Awais Wenxuan Lai Yigui huang Hailin wu Yue Yu lingying Liang Luc Swevers Jingchen sun Min feng Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding College of Animal ScienceSouth China Agricultural UniversityGuangzhouChina Insect Molecular Genetics and Biotechnology National Center for Scientific Research DemokritosInstitute of Biosciences and ApplicationsAthensGreece

The silkworm,a crucial model organism of the Lepidoptera,offers an excellent platform for investigating the molecular mechanisms underlying the innate immune response of insects toward *** the years,researchers worldwide have identified numerous immune-related genes in ***,these identified silkworm immune genes are not well classified and not well known to the scientific *** the availability of the latest genome data of silkworms and the extensive research on silkworm immunity,it has become imperative to systematically categorize the immune genes of silkworms with different database *** this study,we present a meticulous organization of prevalent immune-related genes in the domestic silkworm,using the SilkDB 3.0 database as a reliable source for updated gene ***,utilizing the available data,we classify the collected immune genes into distinct categories:pattern recognition receptors,classical immune pathways,effector genes and ***-depth data analysis has enabled us to predict some potential antiviral ***,we performed antiviral experiments on selected genes,exploring their impact on Bombyx mori nucleopolyhedrovirus *** outcomes of this research furnish novel insights into the immune genes of the silkworm,consequently fostering advancements in the field of silkworm immunity research by establishing a comprehensive classification and functional understanding of immune-related genes in the *** study contributes to the broader understanding of insect immune responses and opens up new avenues for future investigations in the domain of host–pathogen interactions.

关键词： antiviral defense BmNPV Bombyx mori innate immunity SilkDB 3.0

Liver transplantation using an otherwise-wasted partial liver resection graft

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Hepatobiliary & Pancreatic Diseases International 2025年第1期24卷 29-34页

作者： Yong-Sheng Xiao Yi-feng He Xiao-wu huang Zhao-You Tang Jia Fan Jian Zhou Department of Liver Surgery&Transplantation Zhongshan HospitalFudan UniversityShanghai 200032China

Liver transplantation represents a complex surgical procedure and serves as a curative treatment for patients presenting an acute or chronic end-stage liver disease, or carefully selected liver malignancy. A significant gap still exists between the number of available donor organs and potential recipients. The use of an otherwise-wasted resected liver lobe from patients with benign liver tumors is a new, albeit small, option to alleviate the allograft shortage. This review provides evidence that resected liver lobes may be used successfully in liver transplantation.

关键词： Otherwise-wasted resected liver lobe Partial liver resection graft Liver transplantation Alternative liver transplantation technique Liver resection Benign hepatic tumor Hemangioma Focal nodular hyperplasia