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Repeated Wildfires in the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian Ages) in Northwestern China

Acta Geologica Sinica(English Edition) 2022年第5期96卷 1752-1763页

作者： HOU Haihai SHAO Longyi LIANG Guodong TANG Yue zhang huajie zhang Jiaqiang College of Mining Liaoning Technical UniversityFuxinLiaoning 123000China College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China Oil&Gas Resource Survey Center China Geological SurveyMinistry of Land and ResourceBeijing 100029China

The coal-bearing strata in the southern Junggar Basin in northwestern China have recently attracted the attention of coal geologists. Its abundance of coal resources is of great interest as there is a potential of unlocking details about the palaeoclimatic information. Coal deposits have the capacity to record wildfire events, even those with inefficient combustions. To characterize wildfire events and palaeoclimatic history of the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian ages), 22 coal samples from borehole cores and coal mines in the southern Junggar Basin were collected and their macerals were analyzed. The results indicated that fusinite and semi-fusinite were the dominant components of inertinite with proportions of 35.27% and 54.67%, respectively. The presence of inertinite is an indicator that wildfires occurred at the time of peat land development, and the widespread occurrence suggests large scale wildfires during the Middle Jurassic. This study proposes a new parameter for the evaluation of wildfire features by combining burning frequency and burning temperature. The comprehensive evaluation index(CEI) was influenced by the lacustrine basin level and ancient plant types from a sequence framework. During the Middle Jurassic, most wildfires were surface fires with low level and ground fire with high level. High oxygen levels were estimated in the lower, middle, and upper members of the Xishanyao Formation with corresponding to 26.78%, 24.55%, and 23.55%, respectively. The high oxygen levels would be the primary cause of repeated wildfires in the Middle Jurassic. These results are helpful for understanding palaeoclimatic changes in the Middle Jurassic.

关键词： wildfire charcoal Middle Jurassic comprehensive evaluation index northwestern China

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Boosting daytime radiative cooling performance with nanoporous polyethylene film

Energy and Built Environment

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Energy and Built Environment 2023年第2期4卷 131-139页

作者： Junwei Liu huajie Tang Ji zhang Debao zhang Shifei Jiao Zhihua Zhou Tianjin Key Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and EngineeringTianjin UniversityTianjin 300350China China Academy of Building Research Beijing 100013China China IPPR International Engineering Co. LtdBeijing 100089China

Radiative cooling without energy consumption and environmental pollution holds great promise as the next-generation cooling technology.To date,daytime radiative cooling performance is still slightly low,especially in humid areas.In this work,we demonstrated that nanoporous polyethylene(Nano PE)film can improve solar reflectivity from 96%to 99%,thus boosting radiative cooling performance.Moreover,the experimental results in humid areas indicate that Nano PE films can improve radiative cooling performance by∼76%in a clear day and 120%in a day with few clouds.Additionally,compared with ordinary PE films,thin Nano PE films have significantly higher weather fastness and mechanical strength.More importantly,nano PE films can scatter part of visible light,thus suppressing the generation of light pollution in practical applications.Lastly,the modeling results reveal that with Nano PE films,more than 95%of China’s areas can achieve daytime cooling performance.Our work can boost the development of radiative cooling technology with a very low cost.

关键词： Daytime radiative cooling Nano PE films Solar reflectivity Radiative cooling performance

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Comprehensive optimization of piezoelectric coefficient and depolarization temperature in Mn-doped Bi_(0.5)Na_(0.5)TiO_(3)-Bi_(0.5)Na_(0.5)TiO_(3)-BaTiO_(3)lead-free piezoceramics

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Journal of Materials Science & Technology 2024年第5期172卷 255-263页

作者： Huashan Zheng Enwei Sun huajie Luo Xiaoyu zhang Yixiao Yang Bin Yang Rui zhang Shantao zhang Wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing100083China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania16802United States of America

Lead-free Bi_(_(0.5))Na_(_(0.5))TiO_(3)(BNT)piezoelectric ceramics have the advantages of large coercive fields and high Curie temperatures.But the improvement of piezoelectric coefficient(d 33)is usually accompanied by a huge sacrifice of depolarization temperature(T d).In this work,a well-balanced performance of d 33 and T d is achieved in MnO_(2)-doped 0.79(Bi_(_(0.5))Na_(_(0.5))TiO_(3))-0.14(Bi_(0.5)K_(0.5)TiO_(3))-0.07BaTiO_(3)ternary ceramics.The in-corporation of 0.25 mol%MnO_(2)enhances the d 33 by more than 40%,while T d remains almost unchanged(i.e.,d 33=181 pC/N,T d=184℃).X-ray diffraction(XRD)shows that an appropriate fraction of the small axis-ratio ferroelectric phase(pseudo-cubic,P c)coexists with the long-range ferroelectric phase(tetrag-onal,T)under this MnO_(2)doping.Piezoelectric force microscopy(PFM)has revealed a special domain configuration,namely large striped and layered macro domains embedded with small nanodomains.This study provides a distinctive avenue to design BNT-based piezoelectric ceramics with high piezoelectric performance and temperature stability.

关键词： BNT-BKT-BT ceramics Mn doping Piezoelectric Depolarization temperature Phase structure

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Biomimetic porous silicon oxycarbide ceramics with improved specific strength and efficient thermal insulation

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Journal of Materials Science & Technology 2024年第1期168卷 185-193页

作者： Zhuoqing zhang Jinghan Li Lei Cao Yu Shi huajie Yang Rui Yang Fan Xie Xing zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Shenyang Aircraft Design and Research Institute Shenyang 110035China

Considering the challenge of aerodynamic heating,the development of high-performance insulating ce-ramic materials with lightweight and low thermal conductivity is crucially important for aerospace vehi-cles to achieve flight at high speed for a long time.In this work,macro-porous silicon oxycarbide(SiOC)ceramics with directional pores(DP-SiOC)(mean pore size of 88.1μm)were prepared using polysiloxane precursors via freeze casting and photocrosslinking,followed by pyrolysis.The DP-SiOC samples were lightweight(density∼0.135 g cm^(-3))with a porosity of 90.4%,which showed good shapability through the molding of polysiloxane precursors.The DP-SiOC samples also exhibited an ultra-low thermal con-ductivity of 0.048 W(m K)^(-1)at room temperature,which can also withstand heat treatment at 1200°C for 1 h.In addition,scaffolds with triply periodic minimal surfaces(TPMS)were fabricated using digital light processing(DLP)printing,which was further filled with polysiloxane precursors for increasing the strength of DP-SiOC.The TPMS scaffolds filled with macro-porous SiOC ceramics(TPMS-DP-SiOC)showed good integration between TPMS and macro-pore structures,which had a porosity∼75%and high specific strength of 9.73×10^(3)N m kg^(-1).The thermal conductivity of TPMS-DP-SiOC samples was 0.255 W(m K)^(-1)at room temperature.The biomimetic TPMS-DP-SiOC ceramics developed in this study are likely used for thermal protection systems.

关键词： Thermal insulation Light weight Macro-porous ceramics SiOC

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Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

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Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo zhang Yuankang Zha Yixing Ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia zhang huajie Yin Tongfei Shi Haimin zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

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Business Model Innovation in China's Semiconductor Industry:A Pathway to Technological Breakthrough

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Frontiers of Business Research in China 2023年第4期17卷 467-497页

作者： WU Xiaobo zhang Xinyue SHEN huajie School of Management Zhejiang UniversityHangzhou 310058China

In the face of intense global competition,the Chinese semiconductor industry grapples with unprecedented challenges.Addressing theissueeof“bottleneck technology”has become a paramount concern among experts from various domains in China.However,the trajectory of the global semiconductor sector is inexorably linked to the innovation of its business models and adherence to the tenets of technological evolution.It can be posited that,without business model innovation,Moore's Law would cease to exist.In the semiconductor arena,where the first-mover advantage wields immense influence,exclusive focus on“technological breakthroughs”froma technical standpoint would invariably constrict itself within existing technological paradigms,leaving it susceptible to external control.This paper undertakes an in-depth examination of pivotal case studies,particularly that of TSMC and Samsung,two enterprises which transcended1their latecomer status and shattered the“glass ceiling”by embracing“business model innovations.”Through a comprehensive analysis,it introduces and delineates two distinctive avenues of business model innovation:paper“reconstruction of the division of labor system”aand“mismatched demand.”Subsequently,tthe researchini vestigates two more cases,SiEn Integrated Circuits Co.,Ltd.and Changguangg Group,exploring specific business modelinnovation paths,“innovation consortium”and“differentiated demand,”pertinentto latecomer semiconductor companies operating in China.Drawing from these insightsand considering thecurrent international competitive landscape and the ramifications of the COVID-19 pandemic,this paper culminates in the synthesis of eight breakthrough trajectories for latecomer semiconductor firms.These pathways are examined through the lenses of technology paradigms(traditional and emerging),market contextss(globalized and deglobalized),and various types of business model innovation(original and secondary).Furthermore,this research offersa comprehensive analysis and discussion concerning the resources,capabiliti

关键词： business model innovation semiconductor industry latecomer disadvantage secondary innovation innovation consortium

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Outstanding electromechanical performance in piezoelectric ceramics via synergistic effects of defect engineering and domain miniaturization

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Journal of Materials Science & Technology 2023年第27期158卷 1-8页

作者： Zhifei zhang Liang Chen huajie Luo Yueyun zhang Yonghao Yao Guanfu Liu He Qi Jun Chen Beijing Advanced Innovation Center for Materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China Hainan University Haikou 570228China

Piezoelectric ceramics with high mechanical quality factor Q_(m) and large piezoelectric coefficient d_(33) are urgently required for advanced piezoelectric applications.However,obtaining both of these prop-erties simultaneously remains a difficult challenge due to their mutually restrictive relationship.Here 0.5Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.5Pb(Zr_(0.3)Ti_(0.7))O_(3) piezoceramic with tetragonal(T)-rich MPB is designed as a matrix to construct the defect engineering by doping low-valent Mn ions.The strong coupling of defect dipole and T-rich phase can effectively hinder the rotation of P_(s),restrict domain wall motion and improve Q_(m).At the same time,the substituted Mn ions will introduce local random field,destroying the long-range or-dering of ferroelectric domain and reducing domain size.The miniaturized domain structure can increase poling efficiency and inhibit the reduction of d_(33).Guided by this strategy,Q_(m) has increased by more than 10 times and d_(33) has only decreased by about 25%.The optimized electromechanical performance with Q_(m)=822,d_(33)=502 pC/N,k_(p)=0.55 and tanδ=0.0069 can be obtained in the present study.

关键词： PNN-PZT ceramics Defect engineering Domain miniaturization High mechanical quality factor Q_(m) Large piezoelectric coefficient d_(33)

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Genomic convergence underlying high-altitude adaptation in alpine plants

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Journal of Integrative Plant Biology 2023年第7期65卷 1620-1635页

作者： Xu zhang Tianhui Kuang Wenlin Dong Zhihao Qian Huajie Zhang Jacob BLandis Tao Feng Lijuan Li Yanxia Sun Jinling Huang Tao Deng Hengchang Wang Hang Sun CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture The Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Center of Conservation Biology Core Botanical GardensThe Chinese Academy of SciencesWuhan 430074China Yunnan International Joint Laboratory for Biodiversity of Central Asia Key Laboratory for Plant Diversity and Biogeography of East AsiaKunming Institute of BotanyThe Chinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14850USA BTI Computational Biology Center Boyce Thompson InstituteIthacaNew York 14853USA State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China Department of Biology East Carolina UniversityGreenvilleNorth Carolina 27858USA

Evolutionary convergence is one of the most striking examples of adaptation driven by natural selection.However, genomic evidence for convergent adaptation to extreme environments remains scarce.Here, we assembled reference genomes of two alpine plants, Saussurea obvallata(Asteraceae)and Rheum alexandrae(Polygonaceae), with 37,938 and 61,463 annotated protein-coding genes. By integrating an additional five alpine genomes,we elucidated genomic convergence underlying high-altitude adaptation in alpine plants. Our results detected convergent contractions of diseaseresistance genes in alpine genomes, which might be an energy-saving strategy for surviving in hostile environments with only a few pathogens present.We identified signatures of positive selection on a set of genes involved in reproduction and respiration(e.g., MMD1, NBS1, and HPR), and revealed signatures of molecular convergence on genes involved in self-incompatibility, cell wall modification,DNA repair and stress resistance, which may underlie adaptation to extreme cold, high ultraviolet radiation and hypoxia environments. Incorporating transcriptomic data, we further demonstrated that genes associated with cuticular wax and flavonoid biosynthetic pathways exhibit higher expression levels in leafy bracts, shedding light on the genetic mechanisms of the adaptive “greenhouse” morphology. Our integrative data provide novel insights into convergent evolution at a high-taxonomic level,aiding in a deep understanding of genetic adaptation to complex environments.

关键词： adaptation alpine plants evolutionary rates genomic convergence “greenhouse”morphology high altitude

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Litho-Asym Vnet: super-resolution lithography modeling with an asymmetric V-net architecture

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Science China(Information Sciences) 2023年第12期66卷 301-302页

作者： Qing zhang Yuhang zhang Wei LU huajie HUANG Zheng ZHONG Congshu ZHOU Yongfu LI Department of Micro-Nano Electronics and Mo E Key Lab of Artificial Intelligence Shanghai Jiao Tong University Primarius Technologies Co. Ltd.

Lithography simulation is key to the preparation of mask data and verification of mask patterns [1], which enhances design-to-wafer fidelity and minimizes distortions. However,the complexity of lithography simulation has tremendously increased with the decrease in feature size, prolonging the simulation cycle. Hence, an accurate and fast lithography simulation is in great demand.

关键词： Optical resolving power

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A novel vanadium complex VO(p-dmada)inhibits neuroinflammation induced by lipopolysaccharide

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Chinese Chemical Letters 2023年第10期34卷 209-214页

作者： Zhijun He Xiaoqian Li Huajie Zhang Xin Liu Shuangxue Han Anwar Abdurahman Liming Shen Xiubo Du Nan Li Xiaoda Yang Qiong Liu Shenzhen Key Laboratory of Marine Biotechnology and Ecology College of Life Sciences and OceanographyShenzhen UniversityShenzhen 518055China National R&D Center for Se-rich Agricultural Products Processing Hubei Engineering Research Center for Deep Processing of Green Se-rich Agricultural ProductsSchool of Modern Industry for Selenium Science and EngineeringWuhan Polytechnic UniversityWuhan 430023China Shenzhen Bay Laboratory Shenzhen 518055China State Key Laboratories of Natural and Biomimetic Drugs Department of Chemical BiologySchool of Pharmaceutical SciencesPeking University Health Science CenterBeijing 100191China Department of Pharmacy Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020China Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions Shenzhen 518055China

Uncontrolled microglial activation is decisively involved in the neuroinflammatory pathogenesis of brain diseases. Consequently, suppression of microglial overactivation appears to be a strategy for the prevention of nerve injury. In this paper, a novel vanadium complex, vanadyl N-(p-N,Ndimethylaminophenylcarbamoylmethyl)iminodiacetate(VO(p-dmada)), was synthesized from vanadyl sulfate and N,N-dimethyl-p-phenylenediamine, which was structurally characterized by Fourier transform infrared spectrum and ESI-MS analysis. The effect of VO(p-dmada) on neuroinflammation was investigated by using the models of lipopolysaccharide(LPS)-induced BV2 microglial cells and BALB/c mice.Our data demonstrated that VO(p-dmada) significantly suppressed microglial activation by downregulating inflammatory mediators and associated proteins, and inactivating nuclear factor-κ B(NF-κ B) signaling pathway. VO(p-dmada) also upregulated peroxisome proliferator activated receptor gamma(PPARγ) by reducing transglutaminase 2 and heat shock protein 60 expression. Co-treatment with PPARγ antagonist GW9662 significantly impeded the inhibitory effect of VO(p-dmada) on LPS-induced neuroinflammation.These cumulative findings demonstrated that VO(p-dmada) is a potential new drug for the treatment of neuroinflammation-related neurodegenerative diseases.

关键词： Vanadium Vanadyl N-(p-N,Ndimethylaminophenylcarbamoylmethyl)iminodiacetate (VO(p-dmada)) Neuroinflammation Microglia Proteomics Peroxisome proliferator activated receptor gamma(PPARγ)

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