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Pursue the nature of science: Advocate for a better research environment

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The Innovation 2024年第5期5卷 3-4页

作者： Ji dai Shenzhen Technological Research Center for Primate Translational Medicine Shenzhen-Hong Kong Institute of Brain ScienceShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China CAS Key Laboratory of Brain Connectome and Manipulation the Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Guangdong Provincial Key Laboratory of Brain Connectome and Behavior Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China

WHAT IS REAL SCIENCE?Science is often viewed through the lens of its tangible outcomes—publications,grants,academic titles,and *** markers of success in the academic world are undoubtedly important and serve as measures of productivity and ***,focusing solely on these external rewards risks oversimplifying the true essence of science and overlooking its fundamental purpose—the pursuit of knowledge through a process of discovery.1 At its core,science is a systematic and methodical approach to understanding the natural world,unraveling its mysteries,and uncovering the underlying principles that govern the *** is a process of inquiry and exploration that is driven by curiosity,creativity,and a relentless quest for truth(Figure 1).Science is not merely a means to an end but a journey of discovery that transcends individual accomplishments and external *** example is the study of gravitational waves,which are ripples in the fabric of spacetime and are predicted by Einstein’s theory of general *** 2015,the Laser Interferometer Gravitational-Wave Observatory(LIGO)detected gravitational waves for the first *** a major scientific breakthrough was the result of a collaboration between physicists and engineers from multiple institutions around the world,and it was also the result of pure curiosity.

关键词： doubt breakthrough Figure

Metallographic investigationof first full-sizehigh-Jc Nb_(3)Sn cable-in-conduit conductor aftercyclicloadingtests

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Superconductivity 2024年第1期9卷 1-8页

作者： chao dai Yunhao Liu Zichuan Guo Yu Wu Arend Nijhuis Tianjun Xue Zuojiafeng Wu Jinggang Qin Huainan New Energy Research Center Huainan 232000People’s Republic of China University of Twente EnergyMaterials and SystemsFaculty of Science and TechnologyEnschede 7500AENetherlands University of Science and Technology of China Hefei 230026People’s Republic of China Baiyin Non-ferrous Changtong Wire&Cable Co.Ltd BaiyinGansu 730900People’s Republic of China Longteng Mechanical and Electrical Co. LtdYiChun 336000People’s Republic of China

In order to verify the feasibility of applying high-Jc Nb_(3)Sn strand in fusion magnet,a full-size cable-in-conduit conductor(CICC)with short twist pitch(STP)cable pattern was manufactured and tested in SULTAN facility at SPC,*** levels of cyclic electromagnetic(EM)load were applied on the sample stepwise,no visible decrease of current sharing temperature(TcsT was observed until the EM load increased to 80 kA×10.8 T,after that the Tcs decreased dramatically with the EM cycles,which suggested that irreversible deformation,causing a change in the strain state,or even damage has occurred in the superconducting *** investigating the reason which caused the conductor performance degradation,the tested conductor was dissected for metallographic *** segments which subjected to different EM loads were extracted from one of the legs,the geometric feature changes of the cable cross-sections were analyzed and compared.A good correlation was found between the decrease of the Tcs and deformation of the cable cross section.A mass of cracks were found on the sub-elements of strands in the segment which subjected to highest EM load,but the amount of crack is much lower in other *** the analyses,it is speculated that the critical EM load which causes irreversible degradation is between 850 kN/m and 870 kN/m for this *** results could be a reference in high-Jc Nb_(3)Sn CICC design.

关键词： High‐Jc Nb_(3)Sn Cable‐in‐conduit conductor Metallography

Even-odd layer-dependent multiferroic in freestanding rare-earth orthorhombic perovskite

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 151-157页

作者： Shaowen Xu Fanhao Jia Ning dai School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Department of Physics College of ScienceHangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

Freestanding oxide perovskites possess strong interlayer coupling between adjacent atomic layers,thus exerting a determinative effect on the magnetism and ferroelectricity of these atomic-scale ***,we propose an effective strategy to manipulate magnetism and ferroelectricity in freestanding rare-earth orthorhombic perovskite via modulation of layer *** performing first-principles calculations,an even-odd oscillation is demonstrated in few-layer GdAlO_(3)perovskite(GAP).Specifically,odd-layer systems with charged atomic layers are ferromagnetic polar metals,while even-layer systems are antiferromagnetic ferroelectric *** thickness-dependent magnetic phase transition originates from carrier doping,as rationalized by the Stoner ***,we demonstrate the promotion of in-plane ferroelectricity via the concurrent application of two distinct antiferrodistortive displacements,each driven by formation and breaking of *** multiferroic phases may emerge in other transition metal oxide perovskites supporting multiple valence states,e.g.,few-layer Gd MO_(3)(M=V,Cr,Mn,and Ni).This work puts forward a strategy for layer thickness engineering of magnetism and ferroelectricity in 2D oxide perovskite multiferroic materials.

关键词： few-layer rare-earth perovskite multiferroicity size effect first principles calculations

A review on vanadium extraction techniques from major vanadium-containing resources

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Rare Metals 2024年第9期43卷 4115-4131页

作者： Yin-Hui Wang Yi-Fan Wang Yu-Ting Li Chang Wu Xiu-Li Han Ning-Ning Zhao Ze-Kun Zhang Lei dai Ling Wang Zhang-xing He College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources Tangshan 063210China College of Chemical Engineering North China University of Science and TechnologyTangshan 063009China

The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium,emphasizing the need to ensure the sustainability of vanadium *** vanadium slag and stone coal,generated during the smelting process of vanadium–titanium magnetite,serve as primary raw materials for vanadium *** paper reviews the process mineralogy of converter vanadium slag and stone coal,encompassing the chemical and physical phase compositions of the raw materials and the state of vanadium *** aim is to establish a theoretical foundation for the mechanistic study of the vanadium extraction techniques and to provide a reference for the optimization of the process *** paper systematically summarizes the current vanadium extraction technology from converter vanadium slag,covering roasting,direct leaching,sub-molten salt method,and the technology and research status of vanadium extraction from stone *** importantly,it identifies key issues in the current vanadium extraction techniques and challenges faced in actual production,based on the analysis of the current vanadium extraction process and mechanism *** forward feasibility and prospects for the development of vanadium extraction technology are outlined.

关键词： Converter vanadium slag Stone coal Process mineralogy Vanadium extraction process Mechanism research

Spontaneous ignition of corrugated cardboard under dynamic high radiant flux

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Defence Technology（防务技术） 2024年第10期40卷 65-77页

作者： Liu Liu Yan Gu Hong Yang xing Wang Yang Zhou Xiaogan dai Yong Han Shanggang Wen Ming Li Congmei Lin Changgen Feng Fei Tang Yushi Wen Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China Institute of Applied Physics and Computational Mathematics China Academy of Engineering PhysicsBeijing 100088China

Understanding the response of solid combustibles under high radiant fluxes is critical in predicting the thermal damage from extreme *** the more moderate radiant fluxes in conventional hydrocarbon fires,extreme events such as strong explosion,concentrated sunlight and directed energy can generate dynamic radiant fluxes at the MW/m^(2) level,creating a unique threat to *** study investigates the pyrolysis and spontaneous ignition behaviors of corrugated cardboard by using both experimental and numerical methods,under 10-cm dynamic high radiant fluxes ranging from 0.2 to 1.25 MW/m^(2) for 10 *** spontaneous ignition process at dynamic high radiant fluxes was recorded and *** ignition modes were found at the critical radiant flux of 0.4 MW/m^(2),namely hot-gas spontaneous ignition and hot-residue piloted *** latter is not the focus of this paper due to its extremely small probability of *** research reveals that the increase in flux intensity induces shorter delay times for both pyrolysis and ignition,lower ignition energy density,along with a corresponding rise in the critical mass flux and surface temperature at ignition *** simulation results are generally aligned with the experimental findings,despite some divergences may be attributed to model simplifications and parameter *** work contributes to a deeper insight into material behavior under extreme radiation,with valuable implications for fire safety and hazard assessment.

关键词： Extreme radiation Fire safety Corrugated cardboard Pyrolysis Ignition temperature

Exploration of Strong Metal-Support Interaction in Heterogeneous Catalysts by in situ Transmission Electron Microscopy

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Chinese Journal of Chemistry 2024年第9期42卷 1004-1008页

作者： Yongjun Jiang Sheng dai Key Laboratoryfor Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The phenomenon of strong metal-support interaction(SMSI)observed in supported metal catalysts,usually accompanied by the formation of the encapsulation layer on metal nanoparticles,has attracted extensive research attention due to its significance in heterogeneous ***,great progress has been made in recent years in investigating SMSI by in situ transmission electron microscopy(TEM),along with an enhanced comprehension of the underlying mechanisms governing SMSI *** emerging topic summarizes recent progress utilizing in situ TEM to study the interaction between metal and support and the relationship between the structure and performance of the supported catalyst under reaction conditions.A brief perspective about the use of in situ TEM for further study of SMSI is also presented,showing prospects in this field that will stimulate further upsurging research in promoting the catalytic efficiency of supported catalysts.

关键词： Heterogeneous catalysis In situ TEM Strong metal-support interaction Structure changes Interfaces Structural evolution

A cell transcriptomic profile p ovides insights into adipocytes of porcine mammary gland across development

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Journal of Animal Science and Biotechnology 2024年第1期15卷 182-200页

作者： Yongliang Fan Long Jin Zhiping He Tiantian Wei Tingting Luo Jiaman Zhang Can Liu Changjiu dai chao A Yan Liang Xuan Tao Xuebin Lv Yiren Gu Mingzhou Li State Key Laboratory of Swine and Poultry Breeding Industry College of Animal Science and TechnologySichuan Agricultural UniversityChengdu 611130China Key Laboratory of Qinghai‑Tibetan Plateau Animal Genetic Resource Reservation and Utilization Southwest Minzu UniversityChengdu 610041China Animal Breeding and Genetics Key Laboratory of Sichuan Province Sichuan Animal Science AcademyChengdu 610000China

Background Studying the composition and developmental mechanisms in mammary gland is crucial for healthy growth of newborns. The mammary gland is inherently heterogeneous, and its physiological function dependents on the gene expression of multiple cell types. Most studies focused on epithelial cells, disregarding the role of neighboring *** Here, we constructed the largest transcriptomic dataset of porcine mammary gland cells thus far. The dataset captured 126,829 high-quality nuclei from physiological mammary glands across five developmental stages(d 90 of gestation, G90;d 0 after lactation, L0;d 20 after lactation, L20;2 d post natural involution, PI2;7 d post natural involution, PI7). Seven cell types were identified, including epithelial cells, adipocytes, endothelial cells, fibroblasts cells, immune cells, myoepithelial cells and precursor cells. Our data indicate that mammary glands at different developmental stages have distinct phenotypic and transcriptional signatures. During late gestation(G90), the differentiation and proliferation of adipocytes were inhibited. Meanwhile, partly epithelial cells were completely differentiated. Pseudo-time analysis showed that epithelial cells undergo three stages to achieve lactation, including cellular differentiation, hormone sensing, and metabolic activation. During lactation(L0 and L20), adipocytes area accounts for less than 0.5% of mammary glands. To maintain their own survival, the adipocyte exhibited a poorly differentiated state and a proliferative capacity. Epithelial cells initiate lactation upon hormonal stimulation. After fulfilling lactation mission, their undergo physiological death under high intensity lactation. Interestingly, the physiological dead cells seem to be actively cleared by immune cells via CCL21-ACKR4 pathway. This biological process may be an important mechanism for maintaining homeostasis of the mammary gland. During natural involution(PI2 and PI7), epithelial cell populatio

关键词： Adipocytes Cell–cell interaction Development Mammary gland snRNA-seq

SEMI-PROXIMAL POINT METHOD FOR NONSMOOTH CONVEX-CONCAVE MINIMAX OPTIMIZATION

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Journal of Computational Mathematics 2024年第3期42卷 617-637页

作者： Yuhong dai Jiani Wang Liwei Zhang LSEC ICMSECAMSSChinese Academy of SciencesBeijing 100190China School of Mathematical SciencesUniversity of Chinese Academy of SciencesBeijing 100049China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences Dalian University of TechnologyDalian 116024China

Minimax optimization problems are an important class of optimization problems arising from modern machine learning and traditional research *** there have been many numerical algorithms for solving smooth convex-concave minimax problems,numerical algorithms for nonsmooth convex-concave minimax problems are *** paper aims to develop an efficient numerical algorithm for a structured nonsmooth convex-concave minimax problem.A semi-proximal point method(SPP)is proposed,in which a quadratic convex-concave function is adopted for approximating the smooth part of the objective function and semi-proximal terms are added in each *** construction enables the subproblems at each iteration are solvable and even easily solved when the semiproximal terms are cleverly *** prove the global convergence of our algorithm under mild assumptions,without requiring strong convexity-concavity *** the locally metrical subregularity of the solution mapping,we prove that our algorithm has the linear rate of *** numerical results are reported to verify the efficiency of our algorithm.

关键词： Minimax optimization Convexity-concavity Global convergence Rate of con-vergence Locally metrical subregularity

Potential effects of automated driving on vehicle travel demand: A comparison of three case cities

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 348-361页

作者： Jingchen dai Ruimin Li Zhiyong Liu School of Civil Engineering Tsinghua UniversityBeijing 100084China Hang Lung Center for Real Estate Tsinghua UniversityBeijing 100084China School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China

Automated vehicles(AVs)hold the potential to reduce road accidents,mitigate traffic congestion,and improve travel ***,the possible countervailing impacts from the changes in underserved populations’vehicle travel demand tend to be *** determine the vehicle travel demand changes that resulted from underserved populations aged between 6 and 80,this paper explores the latent effect of AVs on vehicle kilometers traveled(VKT)in a fully AV environment using person trip survey data from the cities of Sanya,Shijiazhuang,and Shenzhen in *** paper uses the natural decline hypothesis of travel demand and proposes a regression model to investigate the difference among the cities’latent vehicle travel *** show that the average VKT of the overall population in Sanya,Shijiazhuang,and Shenzhen increased by 33.4%,47.0%,and46.8%,*** analysis of the regression model confirms that the current travel behavior of individuals can affect the degree of increase in their average *** AVs into public transport,increasing the acceptance of automated shared mobility options,transforming road space use type,and prototyping AV designs with various features and needs are potential methods to cope with the countervailing *** total VKT of the overall population increased by approximately 10%-25%depending on the *** conclusions of this paper provide informative insights into the evaluation of VKT for underserved populations and contribute to the deployment of AVs to address equity and inclusion issues.

关键词： Automated vehicles Vehicle kilometers traveled Aging population Travel behavior Natural decline hypothesis