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Oxygen isotopic (^(17)O-^(18)O) heterogeneity in Archaean continental nucleus, North china Craton

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chinese Science Bulletin 1999年第24期44卷 2267-2269页

作者： liu Jianzhong, ZHANG Fuqin, li chunlai and WANG Shijie institute of geochemistry , chinese academy of sciences , guiyang 550002 , china institute of Geophysics , chinese academy of sciences , Beijing 100101 , china institute of geochemistry Chinese Academy of Sciences Guiyang China institute of Geophysics Chinese Academy of Sciences Beijing China

The oxygen isotopic data for amphibolites from Archaean continental nucleus, North china Craton indicate that ( i ) the evolving lines structured by the data are parallel to the geoselenic evolving line, which means that the parent materials of these continental nucleus o-riginated from solar matter; ( ii ) different intercepts for these evolving lines manifest that oxy-

关键词： North china Craton oxygen isotope (I7O-18O ) heterogeneity.

Enhanced ferroelectric and improved leakage of BFO-based thin films through increasing entropy strategy

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2263-2273页

作者： Dongfei Lu Guoqiang Xi Hangren li Jie Tu Xiuqiao liu Xudong liu jianjun Tian linxing Zhang institute for Advanced Materials Technology University of Science and Technology BeijingBeijing 100083China

BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant ***,BFO suffers from a large leakage current,resulting in poor ferroelectric ***,the sol-gel method was used to deposit a series of BFO-based thin films on fluorine-doped tin oxide substrates,and the effects of the substitution of the elements Co,Cu,Mn(B-site)and Sm,Eu,La(A-site)on the crystal structure,ferroelectricity,and leakage current of the BFO-based thin films were *** confirmed that lattice distortion by X-ray diffraction can be attributed to the substitution of individual elements in the BFO-based *** and Eu substitutions contribute to the lattice distortion in a pseudo-cubic structure,while La is biased toward *** force microscopy confirmed that reversible switching of ferroelectric domains by nearly 180°can be realized through the prepared *** ferroelectric hysteresis loops showed that the order for the polarization contribution is as follows:Cu>Co>Mn(B-site),Sm>La>Eu(A-site).The current density voltage curves indicated that the order for leakage contribution is as follows:Mnlitates the formation of dense grains,and the grain size distribution statistics proved that La element promotes the reduction of grain size,leading to the increase of grain boundaries and the reduction of ***,a Bi_(0.985)Sm_(0.045)La_(0.03)Fe_(0.96)Co_(0.02)Cu_(0.02)O_(3)(SmLa-CoCu)thin film with a qualitative leap in the remnant polarization from 25.5(Bi_(0.985)Sm_(0.075)FeO_(3))to 98.8µC/cm^(2)(SmLa-CoCu)was prepared through the syner-gistic action of Sm,La,Co,and Cu *** leakage current is also drastically reduced from 160 to 8.4 mA/cm^(2)at a field strength of 150 kV/***,based on the increasing entropy strategy of chemical engineering,this st

关键词： increasing entropy synergistic ferroelectric film remnant polarization leakage current

geochemistry, zircon U–Pb geochronology, and Hf isotopes of S-type granite in the Baoshan block, constraints on the age and evolution of the Proto-Tethys

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Acta Geochimica 2024年第1期43卷 40-58页

作者： jianjun Zhang Chuanlong Mou Chendong liu Yong Zhang Ting Chen Hualiang li institute of Geological Survey East China University of TechnologyNanchang 330013China School of Earth sciences East China University of TechnologyNanchang 330013China Chengdu Geological Survey Center Chengdu 610081China School of Water Resources&Environmental Engineering East China University of TechnologyNanchang 330013China

geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peraluminous rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with minor involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a non-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peraluminous granite to emerge.

关键词： Baoshan block Early Paleozoic Granite geochemistry Zircon Geochronology Hf isotope

Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science china(Technological sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2, WANG Shijie2, FENG Junming2, li chunlai1, OUYANG Ziyuan1,2, liu Jianzhong1 & li Xiaobiao2 1. National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china 2. State Key Laboratory of Environmental geochemistry, institute of geochemistry, chinese academy of sciences, guiyang 550002, china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2+Fe2O4 and Fe2O3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2-1.5, μ ″ = 1.0-1.2, respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

Diffusion and reaction mechanism of limestone and quartz in fluxed iron ore pellet roasting process

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 485-497页

作者： Yufeng Guo Jinlai Zhang Shuai Wang jianjun Fan Haokun li Feng Chen Kuo liu lingzhi Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Technology Center Taiyuan Iron Steel(Group)Co.Ltd.(TISCO)Taiyuan 030003China

The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking *** this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple *** electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting *** results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of *** the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively *** order of magnitude of interdiffusion coefficient of Fe_(2)O_(3)-CaO diffusion couple was 10^(−10) m^(2)·s^(−1) at a roasting temperature of 1200℃for 9 ***_(2)Fe_(2)O_(5) was the initial product in the Fe_(2)O_(3)-CaO-SiO_(2) diffusion interface,and then Ca_(2)Fe_(2)O_(5) continued to react with Fe_(2)O_(3) to form CaFe_(2)O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2) into CaFe_(2)O_(4),which can strengthen the consolidation of fluxed ***,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed *** addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed.

关键词： fluxed iron ore pellet limestone hematite quartz diffusion reaction

Analytical Model and Topology Optimization of Doubly-fed Induction Generator

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 162-169页

作者： Lu Sun Haoyu Kang Jin Wang Zequan li jianjun liu Yiming Ma libing Zhou the State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE Dongfang Electric Machinery Co. LtdDongfang Electric CorporationDeyangChina CSG PGC Energy Storage Research institute Southern Power Grid Energy Storage Co.LtdGuangzhou 510630China

As the core component of energy conversion for large wind turbines,the output performance of doubly-fed induction generators (DFIGs) plays a decisive role in the power quality of wind *** realize the fast and accurate design optimization of DFIGs,this paper proposes a novel hybriddriven surrogate-assisted optimization *** firstly establishes an accurate subdomain model of DFIGs to analytically predict performance ***,taking the inexpensive analytical dataset produced by the subdomain model as the source domain and the expensive finite element analysis dataset as the target domain,a high-precision surrogate model is trained in a transfer learning way and used for the subsequent multi-objective optimization *** on this model,taking the total harmonic distortion of electromotive force,cogging torque,and iron loss as objectives,and the slot and inner/outer diameters as parameters for optimizing the topology,achieve a rapid and accurate electromagnetic design for ***,experiments are carried out on a 3MW DFIG to validate the effectiveness of the proposed method.

关键词： Doubly-fed induction generators Accurate subdomain model Surrogate-assisted Transfer learning

Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region

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Journal of Ocean University of china 2024年第3期23卷 605-617页

作者： ZHANG Shuqin liAO Qinghua liu Chunlei GAO Xiaoyu LONG Jingchao li Pengyuan XU jianjun College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China South china Sea institute of Marine Meteorology Guangdong Ocean UniversityZhanjiang 524088China CMA-GDOU Joint Laboratory for Marine Meteorology Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong ProvinceGuangdong Ocean UniversityZhanjiang 524088China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Marine Meteorology Ocean-Atmosphere Interaction and Climate LaboratoryKey Laboratory of Physical OceanographyOcean University of ChinaQingdao 266100China

Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension *** most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing *** EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing *** low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate *** diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this *** cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low *** relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing *** non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification.

关键词： explosive cyclone diabatic heating cyclonic-vorticity advection rapid intensification the Kuroshio/Kuroshio Extension region

Molecular compositions and sources of organic aerosols at a rural site on the Guanzhong Plain,Northwest china:The importance of biomass burning

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Particuology 2024年第6期89卷 44-56页

作者： Yali liu Minxia Shen Haijiao liu Wenting Dai Weining Qi Yifan Zhang Lu li Yue Cao Xin Wang Xiao Guo Yingkun Jiang jianjun li State Key Laboratory of Loess and Quaternary Geology Key Lab of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Xi'an institute for Innovative Earth Environment Research Xi'an 710061China National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain ShaanxiChina

The concentration of PM_(2.5)has considerably reduced in recent years,but remains relatively high in *** particular,the increasing contribution of organic compounds to PM_(2.5)generates popular pressure for further reductions,resulting in an urgent need to study organic aerosol(OA).To investigate the molecular composition and source contribution of OA in the rural area of the Guanzhong Plain,Northwest china,PM_(2.5)samples were collected during 3–23 August 2016 and 5–20 January 2017 and studied for more than 100 organic tracer *** mean concentration of total measured organic compounds is 662±296 ng/m^(3)in summer and 3258±1925 ng/m^(3)in *** is the most abundant single compound found throughout the sampling period,which is a crucial tracer for biomass burning emissions,preliminary suggesting that biomass burning is an essential source of *** summer,organic compounds such as lipid compounds,sugar compounds,and polycyclic aromatic hydrocarbons(PAHs),more come from higher plants,wood burning,vehicle exhausts,plastic waste,and other direct emission *** PAHs(OPAHs),nitrophenols,and phthalic acids more come from the atmosphere through the oxidation reaction of aromatic precursors,especially photochemical ***,in winter,most of the increases in concentrations of organic compounds are attributed to biomass *** analysis of a haze event(14–19 January 2017)during the winter sampling period shows that the increases in the concentration of organic compounds are unaccompanied by strong secondary formation under lower relative humidity(49.1%±13.5%).The main reason for the growth of OA in this haze event is the accumulation of primary OA(POA).The source apportionment by the positive matrix factorization(PMF)model shows that biomass burning(37.1%)is the primary source of OA in the rural regions of the Guanzhong Plain,especially in winter(40.6%).The contribution of secondary formation decreases from 26.0%in summer t

关键词： Organic aerosol Molecular composition Seasonal variation Source apportionment Guanzhong Plain

Electrochemical protein biosensors for disease marker detection:progress and opportunities

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Microsystems & Nanoengineering 2024年第3期10卷 1-20页

作者： Lanpeng Guo Yunong Zhao Qing Huang Jing Huang Yanbing Tao jianjun Chen Hua-Yao li Huan liu School of Integrated Circuits Wuhan National Laboratory for OptoelectronicsOptics Valley LaboratoryHuazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education School of Integrated CircuitsAnhui UniversityHefei 230601China School of Optoelectronic Materials and Technology Jianghan UniversityWuhan 430056China Department of Otorhinolaryngology Union HospitalTongji Medical CollegeHuazhong University of Science and Technology1277 Jiefang AvenueWuhan 430022China Wenzhou institute of Advanced Manufacturing Technology Huazhong University of Science and TechnologyWenzhou 325000China

The development of artificial intelligence-enabled medical health care has created both opportunities and challenges for next-generation biosensor *** are extensively used as biological macromolecular markers in disease diagnosis and the analysis of therapeutic *** protein biosensors have achieved desirable specificity by using the specific antibody–antigen binding principle in ***,the active centers of protein biomarkers are surrounded by a peptide matrix,which hinders charge transfer and results in insufficient sensor ***,electrode-modified materials and transducer devices have been designed to increase the sensitivity and improve the practical application prospects of electrochemical protein *** this review,we summarize recent reports of electrochemical biosensors for protein biomarker *** highlight the latest research on electrochemical protein biosensors for the detection of cancer,viral infectious diseases,inflammation,and other *** corresponding sensitive materials,transducer structures,and detection principles associated with such biosensors are also addressed ***,we present an outlook on the use of electrochemical protein biosensors for disease marker detection for the next few years.

关键词： diagnosis specificity Electrochemical