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Paleoenvironmental changes recorded by grain size of loess/paleosol sequence from the Chifeng City,Northeastern China since the Last Glacial

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Journal of Mountain Science 2024年第9期21卷 3068-3082页

作者： Li Juan BRYE Kristofor R zhang Mengge JiANG Zhuodong wANG Qiubing College of Land and Environment Shenyang Agricultural UniversityShenyang 110866China Department of Crop Soiland Environmental SciencesUniversity of ArkansasFayettevilleAR 72701USA

The accumulation processes of loess in northeastern(NE)China record the varying characteristics of the East Asian Monsoons(EAM)and the evolution of the local *** this study,grain size end-member analysis of the Dajiugang(DJG)section deposited since the Last Glacial in Chifeng City,NE China was used to reveal the dynamic depositional characteristics of loess and environmental evolution of NE *** showed that the Chifeng loess comprises three grain size end-members(EM),EM1(7.38μm),EM2(49.4μm)and EM3(90.00μm),indicating the three transport dynamics of dust delivered to the *** EM1 represents atmospheric dust as the *** EM2,mainly derived from relatively distant-sources deposition,and EM3,material transported over a short distance,correspond to the intensity of southwesterly winds and the East Asian winter Monsoon(EAwM),*** of climate reconstruction,combined with other records,showed that the climate was generally cold and dry with a strong EAwM and a weak East Asian summer monsoon(EASM)during the stadial-period[Marine isotope Stage(MiS)4 and MiS 2 stage].The climate was predominantly warm and humid,with weak EAwM and surface winds and strong EASM in interstadial-period(MiS 3 and MiS 1 stage).Comparisons between indicators,e.g.,EM3,the LR04 benthicδ18O stack and summer insolation at 65°N suggest that the strong EAwM is induced by increasing the Northern Hemisphere ice volume and reduced summer solar radiation.

关键词： Loess deposit Grain size end-member Northeastern China Environmental change The Last Glacial

Stretchable poly[2]rotaxane elastomers

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Fundamental Research 2024年第2期4卷 300-306页

作者： Kai Liu Xinhai zhang Dong Zhao Ruixue Bai Yongming wang Xue Yang Jun Zhao Hao zhang w.i Yu Xuzhou Yan School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Chemical Engineering National Engineering Research Center for Dyeing and Finishing of TextilesDonghua UniversityShanghai 201620China

Mechanically interlocked polymers(MiPs)are promising candidates for the construction of elastomeric materials with desirable mechanical performance on account of their abilities to undergo inherent rotational and translational mechanical movements at the molecular ***,the investigations on their mechanical properties are lagging far behind their structural fabrication,especially for linear polyrotaxanes in ***,we report stretchable poly[2]rotaxane elastomers(PREs)w.ich integrate numerous mechanical bonds in the polymeric backbone to boost macroscopic mechanical ***,we have synthesized a hydroxyfunctionalized[2]rotaxane that subsequently participates in the condensation polymerization with diisocyanate to form *** from the peculiar structural and dynamic characteristics of the poly[2]rotaxane,the representative PRE exhibits favorable mechanical performance in terms of stretchability(∼1200%),Young’s modulus(24.6 MPa),and toughness(49.5 MJ/m^(3)).Moreover,we present our poly[2]rotaxanes as model systems to understand the relationship between mechanical bonds and macroscopic mechanical *** is concluded that the mechanical properties of our PREs are mainly determined by the unique topological architectures w.ich possess a consecutive energy dissipation pathway including the dissociation of host−guest interaction and consequential sliding motion of the wheel along the axle in the[2]rotaxane motif.

关键词： Polyrotaxanes Mechanically interlocked polymers Mechanically interlocked molecules Dynamic materials Elastomers

Photonics-assisted joint radar jamming and secure communication in the millimeter-wave band based on CE-LFM-OFDM

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Chinese Optics Letters 2024年第6期22卷 205-211页

作者： Dongju Du Yanyi wang Yingxiong Song Nan Ye Zhengxuan Li Qianwu zhang Junjie zhang Jian Chen Bingyao Cao Jianjun Yu Key Laboratory of Specialty Fiber Optics and Optical Access Networks Joint International Research Laboratory of Specialty Fiber Optics and Advanced CommunicationShanghai UniversityShanghai 200444China Key Laboratory for information Science of Electromagnetic waves(MoE) Fudan UniversityShanghai 200433China

This paper reports a photonics-assisted millimeter-wave (mm-wave) joint radar jamming and secure communication system constructed through a photonic upconversion technique. in the experiments, a 30 GHz constant envelope linear frequency-modulated orthogonal frequency division modulation(CE-LFM-OFDM) signal with an instantaneous bandwidth of 1 GHz is synthesized by encoding 1 GBaud encrypted 16-quadrature amplitude modulation(16-QAM) OFDM signal. The velocity deception jamming is achieved with a spurious suppression ratio over 30 dB. Furthermore, we efficiently execute range deception jamming with a time shift of 10 ns. Simultaneously, the encrypted 16-QAM OFDM signal is successfully transmitted over a 1.2 m wireless link, with a data rate of 4 Gbit/s.

关键词： millimeter-wave radar jamming secure wireless communication

A review of solid-state lithium metal batteries through in-situ solidification

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Science China Chemistry 2024年第1期67卷 67-86页

作者： Pan Xu Zong-Yao Shuang Chen-Zi Zhao Xue Li Li-Zhen Fan Aibing Chen Haoting Chen Elena Kuzmina Elena Karaseva Vladimir Kolosnitsyn Xiaoyuan Zeng Peng Dong Yingjie zhang Mingpei wang Qiang zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China National and Local Joint Engineering Laboratory for Lithium-ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Battery Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos City 017010China Ufa institute of Chemistry UFRC RAS Ufa 450054Russia institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Shanxi Research institute for Clean Energy Tsinghua UniversityTaiyuan 030032China

High-energy-density lithium metal batteries are the next-generation battery systems of choice,and replacing the flammable liquid electrolyte with a polymer solid-state electrolyte is a prominent conduct towards realizing the goal of high-safety and high-specific-energy ***,the inherent intractable problems of poor solid-solid contacts between the electrode/electrolyte and the growth of Li dendrites hinder their practical *** in-situ solidification has demonstrated a variety of advantages in the application of polymer electrolytes and artificial interphase,including the design of integrated polymer electrolytes and asymmetric polymer electrolytes to enhance the compatibility of solid–solid contact and compatibility between various electrolytes,and the construction of artificial interphase between the Li anode and cathode to suppress the formation of Li dendrites and to enhance the high-voltage stability of polymer *** review firstly elaborates the history of in-situ solidification for solid-state batteries,and then focuses on the synthetic methods of solidified ***,the recent progress of in-situ solidification technology from both the design of polymer electrolytes and the construction of artificial interphase is summarized,and the importance of in-situ solidification technology in enhancing safety is ***,prospects,emerging challenges,and practical applications of in-situ solidification are envisioned.

关键词： in-situ solidification polymer electrolyte artificial solid electrolyte interphase rechargeable lithium metal batteries dendrite-free lithium metal anode

Luteolin promotes neuronogenesis in hippocampus of chronic unpredictable mild stress rats and primary hippocampus of fetal rats

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Journal of Traditional Chinese Medicine 2024年第4期44卷 670-679页

作者： LiU Tongtong zhang Xi YANG Hui LiN Xiaoyuan LiU Jian zhang Xiuli GUO Dongw.i ZHAO Hongqing ZOU Manshu LEi Chang LONG Hongping LUO Yan XiANG Yun GE Jinwen wANG Yuhong MENG Pan institute of innovation and Applied Research in Chinese Medicine Hunan University of Chinese MedicineChangsha 410208China the Second People's Hospital of Hunan Province Changsha 410007China The First Affiliated Hospital Hunan University of Chinese MedicineChangsha 410007China Hunan Academy of Chinese Medicine Changsha 410013China

OBJECTiVE:To investigate the effects of luteolin on chronic unpredictable mild stress(CUMS)-induced depressive rats and corticosterone(CORT)-induced depressive primary hippocampal neurons,and to elucidate the mechanism behind the ***:The antidepressant mechanism of luteolin was studied by using CUMS rat model and primary hippocampal neurons in fetal *** vivo,novelty suppressed feeding,open-field and sucrose preference tests as well as Morris water maze were *** content of brain derived neurotrophic factor(BDNF),5-hydroxytryptamine(5-HT),norepinephrine(NE),and dopamine(DA)in serum were detected by enzyme-linked immunosorbent *** mechanisms of luteolin were explored based on neurotrophin and hippocampal neurogenesis,and *** of the septotemporal axis in hippocampus was assayed using the 5-bromo-2-deoxyuridine(BrdU),the expression of BDNF,neurotrophin-3(NT-3),and nerve growth factor(NGF)in hippocampus dentate gyrus region were measured by *** vitro,BDNF,NT-3,tropomyosin receptor kinase B(TrkB),and phosphorylated cyclic adenosine monophosphate responsive element binding protein(p-CREB)were detected through the high content analysis(HCA)to investigate neurotrophin and ***:induction of CUMS in rats induced depressive symptoms,w.ile luteolin significantly enhanced sucrose consumption,decreased feeding latency,increased locomotor activity,escape latency,distance of target quadrant and regulated the content of depressive-like *** analysis revealed that luteolin increased the abundance of new born neurons that had been labeled with BrdU,BrdU+neuronal nuclear antigen,and BrdU+doublecortin in septo-temporal axis of S2(mid-septal)and T3(mid-temporal).Moreover,expression of BDNF,NT-3,and NGF increased significantly in the septo-temporal axis of S2 and *** showed increased expression of BDNF,NT-3,TrkB and p-CREB in primary hippocampal ***:The results provided direct ev

关键词： fetal rats Survival

Heat dissipation enhancement method for finned heat sink for AGV motor driver's iGBT module

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High Technology Letters 2024年第2期30卷 170-178页

作者：刘璇 zhang Mingchao LiU Chengwen ZHOU Chuanan LV Xiaoling School of Mechanical Engineering Hebei University of TechnologyTianjin 300401P.R.China

with the widespread use of high-power and highly integrated insulated gate bipolar transistor(iGBT),their cooling methods have become *** paper proposes a liquid cooling scheme for heavy-duty automated guided vehicle(AGV)motor driver in port environment,and improves heat dissipation by analyzing and optimizing the core component of finned heat ***,the temperature distribution of the initial scheme is studied by using Fluent software,and the heat transfer characteristics of the finned heat sink are obtained through numerical ***,an orthogonal test is designed and combined with the response surface methodology to optimize the structural parameters of the finned heat sink,resulting in a 14.57%increase in the heat dissipation ***,the effectiveness of heat dissipation enhancement is *** work provides valuable insights into improving the heat dissipation of iGBT modules and heat sinks,and provides guidance for their future applications.

关键词： finned heat sink insulated gate bipolar transistor(iGBT)module heat dissipation orthogonal test response surface methodology

Bose–Einstein distribution temperature features of quasiparticles around magnetopolaron in Gaussian quantum wells of alkali halogen ions

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Chinese Physics B 2024年第9期33卷 521-526页

作者： Xin zhang Sarengaowa Shuang Han Ran An Xin-Xue zhang Xin-Ying Ji Hong-Xu Jiang Xin-Jun Ma Pei-Fang Li Yong Sun College of Physics and Electronic information Inner Mongolia Minzu UniversityTongliao028000China institute of Condensed Matter Physics Inner Mongolia Minzu UniversityTongliao 028000China

we have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum *** obtained results showed that under magnetic field effect,magnetopolaron quasiparticle was formed through the interaction of electrons and surrounding *** the same time,magnetopolaron was influenced by phonon temperature statistical law and important energy level shifts down and binding energy *** revealed that lattice temperature and magnetic field could easily affect magnetopolaron and the above results could play key roles in exploring thermoelectric conversion and conductivity of crystal materials.

关键词： temperature effect quantum well asymmetric Gaussian potential magnetopolaron

Ultra-homogeneous dense Ag nano layer enables long lifespan solid-state lithium metal batteries

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Journal of Energy Chemistry 2024年第9期96卷 110-119页

作者： Yaning Liu Tianqi Yang Ruyi Fang Chengw.i Lu Ruojian Ma Ke Yue Zhen Xiao Xiaozheng Zhou wenkui zhang Xinping He Yongping Gan Jun zhang Xinhui Xia Hui Huang Xinyong Tao Yang Xia College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014ZhejiangChina Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesChina Jiliang UniversityHangzhou 310018ZhejiangChina

The unstable electrolyte/lithium(Li)anode interface has been one of the key challenges in realizing high energy density solid-state lithium metal batteries(LMBs)***,a dense and uniform silver(Ag)nano interlayer with a thickness of∼35 nm is designed accurately by magnetron sputtering technology to optimize the electrolyte/Li anode *** Ag nano layer reacts with Li metal anode to in-situ form Li-Ag alloy,thus enhancing the physical interfacial contact,and further improving the interfacial wettability and *** particular,the Li-Ag alloy is inclined to form AgLi phase proved by cryo-TEM and DFT,effectively preventing SN from continuously“attacking”the Li metal anode due to the lower adsorption of succinonitrile(SN)molecules on AgLi than that of pure Li metal,thereby significantly reinforcing the interfacial ***,the enhanced physical and chemical stability of electrolyte/Li anode interface promotes the homogeneous deposition of Li^(+)and inhibits the dendrite *** Li-symmetric cell maintains stable operation for up to 1700 h and the cycling stability of LiFePO_(4)|SPE|Li full cell is remarkably improved at room temperature(capacity retention rate of 91.9%for 200 cycles).This work opens an effective way for accurate and controllable interface design of long lifespan solid-state LMBs.

关键词： Silvernano layer Poly(ethylene oxide) Solid polymer electrolyte Succinonitrile Lithium metal battery

Laser-induced breakdown spectroscopy as a method for millimeter-scale inspection of surface flatness

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Plasma Science and Technology 2024年第9期26卷 148-155页

作者： Jinrui YE Yaju Li Zhao zhang Xinw.i wANG Kew.i TAO Qiang ZENG Liangwen CHEN Dongbin QiAN Shaofeng zhang Lei YANG Xinwen MA institute of Modern Physics Chinese Academy of SciencesLanzhou 730000People’s Republic of China Advanced Energy Science and Technology Guangdong LaboratoryHuizhou 516000People’s Republic of China University of the Chinese Academy of Sciences Beijing 100049People’s Republic of China Key Laboratory of Atomic and Molecular Physics&Functional Materials of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070People’s Republic of China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

A non-contact method for millimeter-scale inspection of material surface flatness via Laser-induced Breakdown Spectroscopy(LiBS)is investigated *** experiment is performed using a planished surface of an alloy steel sample to simulate its various flatness,ranging from 0 to 4.4 mm,by adjusting the laser focal plane to the surface distance with a step length of 0.2 *** is found that LiBS measurements are successful in inspecting the flatness differences among these simulated cases,implying that the method investigated here is *** is also found that,for achieving the inspection of surface flatness within such a wide range,when univariate analysis is applied,a piecewise calibration model must be *** is due to the complex dependence of plasma formation conditions on the surface flatness,w.ich inevitably complicates the inspection *** solve the problem,a multivariate analysis with the help of Back-Propagation Neural Network(BPNN)algorithms is applied to further construct the calibration *** detailed analysis of the model performance,we demonstrate that a unified calibration model can be well established based on BPNN algorithms for unambiguous millimeter-scale range inspection of surface flatness with a resolution of about 0.2 mm.

关键词： laser-induced breakdown spectroscopy machine learning surface flatness