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Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： yang Zhen FU Yong LI Chao cai Xi GUO chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

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Optimization of resource allocation in FDD massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 117-125页

作者： Jun cai chuan Yin Youwei Ding School of Artificial Intelligence and Information Techology Nanjing University of Chinese MedicineNanjing 210046China School of Electronic and Information Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The performance of massive MIMO systems relies heavily on the availability of Channel State Information at the Transmitter(CSIT).A large amount of work has been devoted to reducing the CSIT acquisition overhead at the pilot training and/or CsI feedback stage.In fact,the downlink communication generally includes three stages,i.e.,pilot training,CsI feedback,and data transmission.These three stages are mutually related and jointly determine the overall system performance.Unfortunately,there exist few studies on the reduction of csIT acquisition overhead from the global point of view.In this paper,we integrate the Minimum Mean Square Error(MMSE)channel estimation,Random Vector Quantization(RVQ)based limited feedback and Maximal Ratio Combining(MRC)precoding into a unified framework for investigating the resource allocation problem.In particular,we first approximate the covariance matrix of the quantization error with a simple expression and derive an analytical expression of the received Signal-to-Noise Ratio(SNR)based on the deterministic equivalence theory.Then the three performance metrics(the spectral efficiency,energy efficiency,and total energy consumption)oriented problems are formulated analytically.With practical system requirements,these three metrics can be collaboratively optimized.Finally,we propose an optimization solver to derive the optimal partition of channel coherence time.Experiment results verify the benefits of the proposed resource allocation schemes under three different scenarios and illustrate the tradeoff of resource allocation between three stages.

关键词： Massive MIMO FDD CSIT Resource allocation

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Microstructure and impact behavior of Mg-4Al-5RE-xGd cast magnesium alloys

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Journal of Magnesium and Alloys 2024年第5期12卷 1799-1814页

作者： Jie Wei Qudong Wang Huisheng cai Mahmoud Ebrahimi chuan Lei National Engineering Research Center of Light Alloy Net Forming and Key State Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University

This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd（RE represents La-Ce mischmetal; x = 0, 0.2,0.7 wt.%） alloys cast by high-pressure die casting（HPDC）, permanent mold casting（PMC）, and sand casting（SC） techniques. The results indicated that with increasing Gd content, the grain sizes of the HPDC alloy had a slight change, but the grains of the PMC and SC alloys were significantly refined. Besides, the acicular Al11RE3phase was modified into the short-rod shape under the three casting conditions. The impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack initiation. With increasing Gd content,the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack initiation. The impact stress was higher than the tensile stress, exhibiting a strain rate sensitivity for the mechanical response; however, the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing strain. Abundant dimples covered the fracture surface of the fine-grained HPDC alloys, indicating a typical ductile fracture. Nevertheless, due to the deficient {■} twinning activity and the suppressed grain boundary sliding during the impact event, the HPDC alloys showed insufficient plastic deformation capacity.

关键词： Mg-Al-RE alloy Gadolinium Microstructure Impact behavior

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Pathway Planning of Nuclear Power Development Incorporating Assessment of Nuclear Event Risk

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 500-513页

作者： Xinxin yang Yusheng Xue Bin cai School of Electrical Engineering Southeast UniversityNanjingChinaand they are also with State Grid Electric Power Research Institute(NARI Group Corporation)NanjingChina State Key Laboratory of Smart Grid Protection and Operation Control NanjingChina State Grid Electric Power Research Institute(NARI Group Corporation) NanjingChina

The nuclear event risk(NER)is an important and disputed factor that should be reasonably considered when planning the pathway of nuclear power development(NPD)to assess the benefits and risks of developing nuclear power more objectively.This paper aims to explore the impact of nuclear events on NPD pathway planning.The influence of nuclear events is quantified as a monetary risk component,and an optimization model that incorporates the NER in the objective function is proposed.To optimize the pathway of NPD in the lowcarbon transition course of power supply structure evolution,a simulation model is built to deduce alternative NPD pathways and corresponding power supply evolution scenarios under the constraint of an exogenously assigned carbon emission pathway(CEP);moreover,a method is proposed to describe the CEP by superimposing the maximum carbon emission space and each carbon emission reduction(CER)component,and various CER components are clustered considering the emission reduction characteristics and resource endowments of different power generation technologies.A case study is conducted to explore the impact of NER and its risk valuation uncertainty on NPD pathway planning.The method presented in this paper allows the impact of nuclear events on NPD pathway planning to be quantified and improves the level of coordinated optimization of benefits and risks.

关键词： Low-carbon transition power supply structure evolution nuclear power development(NPD) quantitative analysis nuclear event risk evaluation

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High speed laser cladding as a new approach to prepare ultra-high temperature ceramic coatings

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Journal of Advanced Ceramics 2024年第2期13卷 143-154页

作者： Qiyao Deng Pengfei He chuan Sun yang Li Yue Xing Yujie Wang Jinglong Li Xiubing Liang Xin Wang Yujie Zhou Yujun cai National-Local Joint Engineering Laboratory of Intelligent Manufacturing Oriented Automobile Die&Mould Tianjin University of Technology and EducationTianjin 300222China Defense Innovation Institute Academy of Military ScienceBeijing 100071China School of mechanical engineering Tianjin University of Technology and EducationTianjin 300222China Scientific and Technological Innovation Center Beijing 100012China

Ultra-high temperature ceramic(UHTC)coatings are used to protect the hot-end components of hypervelocity aerocrafts from thermal ablation.This study provides a new approach to fabricate UHTC coatings with high speed laser cladding(HSLC)technology,and places more emphasis on investigating the formation mechanism,phase compositions,and mechanical properties of HSLC-UHTC coatings.Results show that a well-bonded interface between the coating and the tantalum alloy substrate can be formed.The coating is mainly composed of(Zr,Ta)C ceramic solid solution phase with a content of higher than 90% by volume and Ta(W)metal solid solution phase.At a relatively high powder feeding rate,the ZrC ceramic phase appears in the coating while a dense ZrC UHTC top layer with a thickness of up to~50μm is successfully fabricated.As for the mechanical properties of the HSLC coatings,the fracture toughness of the coating decreases with the increase of powder feeding rate.The increase of carbide solid solution phase can significantly improve the high temperature microhardness(552.7±1.8 HV0.5@1000℃).The innovative design of HSLC ZrC-based coatings on refractory alloys accomplishes continuous transitions on microstructure and properties from the substrate to the UHTC top layer,which is a very promising candidate scheme for thermal protection coating.

关键词： high speed laser cladding(HSLC) ultra-high temperature ceramic(UHTC) thermal protection coating microstructure mechanical properties

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Emerging role of regulated cell death in intestinal failure-associated liver disease

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 228-233页

作者： Si-yang Cheng Lu Jiang Ying Wang Wei cai Department of Pediatric Surgery Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition Shanghai 200092China Shanghai Institute for Pediatric Research Shanghai 200092China Division of Pediatric Gastroenterology and Nutrition Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China

Intestinal failure-associated liver disease(IFALD)is a common complication of long-term parenteral nutrition that is associated with significant morbidity and mortality.It is mainly characterized by cholestasis in children and steatohepatitis in adults.Unfortunately,there is no effective approach to prevent or reverse the disease.Regulated cell death(RCD)represents a fundamental biological paradigm that determines the outcome of a variety of liver diseases.Nowadays cell death is reclassified into several types,based on the mechanisms and morphological phenotypes.Emerging evidence has linked different modes of RCD,such as apoptosis,necroptosis,ferroptosis,and pyroptosis to the pathogenesis of liver diseases.Recent studies have shown that different modes of RCD are present in animal models and patients with IFALD.Understanding the pathogenic roles of cell death may help uncover the underlying mechanisms and develop novel therapeutic strategies in IFALD.In this review,we discuss the current knowledge on how RCD may link to the pathogenesis of IFALD.We highlight examples of cell death-targeted interventions aiming to attenuate the disease,and provide perspectives for future basic and translational research in the field.

关键词： Parenteral nutrition Apoptosis Necroptosis Cholestasis Steatosis

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Bioinspired nanotransducers for neuromodulation

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Nano Research 2024年第2期17卷 618-632页

作者： Fan yang Xiang Wu Sa cai Guosong Hong Department of Materials Science and Engineering Stanford UniversityStanfordCA 94305USA Wu Tsai Neurosciences Institute Stanford UniversityStanfordCA 94305USA School of Science Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China

The field of neuromodulation has experienced significant advancements in the past decade,owing to breakthroughs in disciplines such as materials science,genetics,bioengineering,photonics,and beyond.The convergence of these fields has resulted in the development of nanotransducers,devices that harness the synergies of these diverse disciplines.These nanotransducers,essential for neuromodulation,often draw inspiration from energy conversion processes found in nature for their unique modalities.In this review,we will delve into the latest advancements in wireless neuromodulation facilitated by optical,magnetic,and mechanical nanotransducers.We will examine their working principles,properties,advantages,and limitations in comparison to current methods for deep brain neuromodulation,highlighting the impact of natural systems on their design and functionality.Additionally,we will underscore potential future directions,emphasizing how continued progress in materials science,neuroscience,and bioengineering might expand the horizons of what is achievable with nanotransducer-enabled neuromodulation.

关键词： bioinspired synthesis neuromodulation mechanoluminescence focused ultrasound nanotransducers sono-optogenetics

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Intracellular redox potential-driven live-cell synthesis of CdSe quantum dots in Staphylococcus aureus

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Science China Chemistry 2024年第3期67卷 990-999页

作者： cai-Qin Wu An-An Liu Xu Li Jia-Wei Tu Juan Kong Ling-Ling yang Jian-Hong Jia chuan Wang Bin Hu Zhi-Xiong Xie Dai-Wen Pang The Institute for Advanced Studies College of Chemistry and Molecular SciencesCollege of Life SciencesHubei Key Laboratory of Cell HomeostasisWuhan UniversityWuhan 430072China Research Center for Analytical Sciences College of ChemistryState Key Laboratory of Medicinal Chemical BiologyTianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterFrontiers Science Center for Cell Responsesand Haihe Laboratory of Sustainable Chemical TransformationsNankai UniversityTianjin 300071China

Biosynthesized semiconductor quantum dots(QDs) have bright fluorescence,adjustable particle sizes,and environmental friendliness,endowing them with convenience and potential for biological applications.Due to the unclear mechanism of the cellular environment on the live-cell synthesis of QDs,it is still difficult to regulate their optical properties.Here,the critical role of the intracellular redox environment in regulating the fluorescence properties of biosynthesized CdSe QDs in Staphylococcus aureus(S.aureus) has been elucidated.The glutathione peroxidase(GPx) activity directly affects the intracellular H_(2)O_(2) produced in the SeO_(3)^(2-) reduction,which further manipulates the glutathione redox cycle to determine the content of low-valence Seintermediates.As a result,the fluorescence intensity of the synthesized CdSe QDs increases by 60% in the GPx overexpressed cells.The cellular redox potential that is controlled by the GSH redox cycle provides the driving force for the reduction of SeO_(3)^(2-),facilitating the synthesis of CdSe QDs in S.aureus cells.The proposed mechanism of the cellular redox state provides a new perspective for regulating the synthesis of semiconductor nanomaterials in live cells.

关键词： redox H_(2)O_(2) peroxidase quantum dot Staphylococcus aureus

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Heavier Group 14 Congeners of Metalla-isobenzenes:Access to Metalla-isosilabenzene and Metalla-isogermabenzene by One-Pot Reactions

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Chinese Journal of Chemistry 2024年第10期42卷 1121-1127页

作者： Jinyu Zhao Yapeng cai Xin yang Hong Zhang Department of Chemistry Xiamen UniversityXiamenFujian 361005China

Metalla-isosilabenzenes and metalla-isogermabenzenes have been successfully synthesized by the formal[5+1]-cycloaddition of diethynylsilane or diethynylgermane with simple metal complexes.This is the first example of a heavier Group 14 metalla-isobenzene isomer bearing a cumulative double bond motif within a metallacycle.These novel complexes were fully characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis.The stabilization of the cyclic metal-vinylidene complexes has been analyzed using density functional theory(DFT)calculations.When the metalla-isosilabenzenes bearing Si—H bond were treated with the trityl salt as a hydride scavenger,the formation of silylium cation was observed spectroscopically.Both of metalla-isosilabenzenes and metalla-isogermabenzenes can readily undergo migratory insertion reactions to furnish siloles or germoles.

关键词： Metalla-isosilabenzene Metalla-isogermabenzene Density functional calculations Cycloaddition Metallacycles

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Research on wind turbine blade damage based on pre-stressed FBG strain sensors

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Optoelectronics Letters 2024年第2期20卷 83-88页

作者： cai Yujie yang Zhiquan ZHANG Bihua WEI Yufeng Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Faculty of Public Safety and Emergency Management Kunming University of Science and TechnologyKunming 650093China Beijing FBGTECH Optic Electric Technology Co. Ltd.Beijing 100043China1

One of the essential parts of a wind power generator that captures wind energy is the wind turbine blade.The safety of the blades rapidly declines as a wind turbine's operating period grows.For real-time monitoring,a chip-type pre-stressed fiber Bragg grating(FBG)strain sensor was fabricated.The sensor's structure was improved using simulation analysis along with optimization.It was discovered through calibration trials that the pre-stressing method expanded the sensor's range of measurement,guaranteed overall linearity,and prevented the potential hysteresis phenomena during compression.The sensor's final sensitivity was calculated to be 1.970 pm/με,and its linear fitting coefficient was 0.999.Finally,the sensor was used to monitor the wind turbine blades and the strain change curve of the root of a normally functioning blade is found to be a sine curve,which provides a certain reference value for judging whether the blade is damaged in the future.

关键词： blade strain damage

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