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Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang liu Huopo Chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China

Stream Surface Strip Element Method and Simulation of Three-Dimensional Deformation of Continuous Hot Rolled Strip

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Journal of Iron and Steel Research International 2004年第2期11卷 18-24页

作者： liu hong-min WANG ying-rui Yanshan University

A new method,the stream surface strip element method,for simulating the three-dimensional deformation of plate and strip rolling process was *** rolling deformation zone was divided into a number of stream surface(curved surface)strip elements along metal flow traces,and the stream surface strip elements were mapped into the corresponding plane strip elements for analysis and *** longitudinal distributions of the lateral displacement and the altitudinal displacement of metal were respectively constructed to be a quartic curve and a quadratic curve,of which the lateral distributions were expressed as the third-power spline function,and the altitudinal distributions were fitted in the quadratic *** the flow theory of plastic mechanics,the mathematical models of the three-dimensional deformations and stresses of the deformation zone were *** with the streamline strip element method proposed by the first author of this paper,the stream surface strip element method takes into account the uneven distributions of stresses and deformations along altitudinal direction,and realizes the precise three-dimensional analysis and *** simulation example of continuous hot rolled strip indicates that the method and the model accord with facts and provide a new reliable engineering-computation method for the three-dimensional mechanics simulation of plate and strip rolling process.

关键词： hot-rolling strip plate three-dimensional deformation stream surface strip element method unit rolling pressure friction stress tension stress

Passive localization of 3-D near-field sources in coexisted multiplicative noise and additive noise

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 46-51页

作者： liu Guo-hong SUN Xiao-ying College of Communication Engineering Jilin University

By exploiting thvorable characteristics of a uniIbrm cross-array, a passive localization algorithm of narrowband sources in the spherical coordinates （azimuth, elevation and range） is proposed. Based on the properly chosen sensor outputs, we compute the third-order cyclic moment matrices, and exploit a pre-calibration technique to eliminate multiplicative noise. Then, we construct a parallel factor （PARAFAC） model, and adopt trilinear altemating least squares regression （TALS） to estimate three-dimensional （3-D） near-field parameters. The investigated algorithm is efficient in the sense that it can eliminate multiplicative noise and additive noise, provide the improved estimation accuracy, as well as avoid the parameter-pairing procedure. Simulation results are carried out to demonstrate the performance of the proposed algorithm.

关键词： multiplicative stationary noise additive stationary noise higher-order cyclic statistics parallel factor analysis near-field sources

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两种分娩方式对正常生殖道菌群的影响

实用妇产科杂志 2002年第5期18卷 306-307页

作者：丁红刘颖琳梁佩兰林君仪中山医科大学孙逸仙纪念医院广东广州510120

目的 :观察剖宫产和自然分娩两种分娩方式对正常产妇生殖道菌群的影响。方法 :选择 4 8例无易感因素的正常产妇 ,2 0例择期剖宫产 ,2 8例自然分娩 ,分别在术前、术时、术后行阴道液、宫腔液细菌培养 ,分娩前后不使用任何抗生素 ,观察分... 详细信息

目的 :观察剖宫产和自然分娩两种分娩方式对正常产妇生殖道菌群的影响。方法 :选择 4 8例无易感因素的正常产妇 ,2 0例择期剖宫产 ,2 8例自然分娩 ,分别在术前、术时、术后行阴道液、宫腔液细菌培养 ,分娩前后不使用任何抗生素 ,观察分娩期和产褥期生殖道菌群的自然变化和产后感染情况。结果 :剖宫产术前阴道细菌培养阳性率为 6 0 % ,术后为 85 % (P>0 .0 5 ) ,术前宫腔细菌培养为阴性 ,术后为 35 .0 % (P0 .0 5 )。结论 :两种分娩方式均可影响正常生殖道的菌群生态环境 ,造成菌群失调。在无易感因素的条件下 ,不使用抗生素 ,剖宫产与自然分娩的感染率无差异。

关键词：生殖道菌群产褥期感染剖宫产自然分娩细菌培养

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Synthesis of faveolate open-structured Ru-N/C cathode catalyst with high bifunctional activity for rechargeable quasi-solid-state Li-O_(2)batteries

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Nano Research 2025年第1期18卷 351-361页

作者： Tie liu School of Chemistry and Chemical Engineering Heze UniversityHeze 274015China

The constituents and geometric design of cathodic electrocatalyst to achieve high activity and durability are effective but challenging for the development of high-performance Li-O_(2)*** study employs a mild solution precipitation method followed by thermolysis to construct a faveolate open-structured Ru-N/C matrix with a loosely braided network morphology as a bifunctional *** details prove that this hybrid structure is composed of ultrafine Ru globular nanoparticles(ca.2 nm)coated with an N-enriched carbon film and exhibits a valuable beehive through-hole character for rapid mass transport during oxygen redox *** synergistic effect of open-structured and reticular network matrix with metal-N4 coordination induces asymmetric charge distributions with moderate adsorption/desorption behaviour with oxygen ***,this particular Ru-N/C matrix cathode provides a promising Li_(2)O_(2)accommodation space and exhibits superior electrochemical performance in terms of a positive discharge plateau and low charge ***,the assembled batteries also present a high discharge capacity and a long cycle life(exceeding 283 cycles).The density functional theory(DFT)calculations also corroborate the assertion that the Ru-N/C catalyst exhibits robust electronic coupling transfer and superior bifunctional *** such,our work demonstrates that this type of open-structured Ru-N/C matrix is promising for fabricating high-performance quasi solid-state Li-O_(2)batteries.

关键词： ruthenium nitride nitrogen-doped carbon electrocatalyst Li-O_(2)battery

瘦素受体基因20外显子突变对儿童脂质代谢影响的临床研究(英文)

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中国当代儿科杂志 2005年第4期7卷 296-300页

作者：刘长云卢映王永芹刘红英季加芬李振荣李伟华李兰秀郑传利潍坊医学院附属医院儿科山东潍坊261042

目的探讨瘦素受体基因(LEPR)第20外显子突变对脂质代谢的影响及肥胖儿童基因型与血脂的关系。方法用聚合酶链反应限制性片段长度多态性(PCRRFLP)方法及聚丙烯酰胺凝胶电泳分析20外显子的基因突变频率,并测定单纯型肥胖儿童(102例)和健... 详细信息

目的探讨瘦素受体基因(LEPR)第20外显子突变对脂质代谢的影响及肥胖儿童基因型与血脂的关系。方法用聚合酶链反应限制性片段长度多态性(PCRRFLP)方法及聚丙烯酰胺凝胶电泳分析20外显子的基因突变频率,并测定单纯型肥胖儿童(102例)和健康儿童(81例)血清中甘油三脂(TG)、总胆固醇(TC)、高密度脂蛋白(HDL)和低密度脂蛋白(LDL)水平。两组分别测量身高、体重,计算体重指数(BMI)及脂肪百分比。结果肥胖儿童瘦素受体基因的20外显子经PCRRFLP及聚丙烯酰胺凝胶电泳分析,检测出3种基因型G/G,G/A和A/A型。肥胖儿童20外显子3057位G→A突变频率较健康儿童增高(P<0.05)。A/A基因型的肥胖儿童其血清TG(1.8±0.5mmol/Lvs1.0±0.4mmol/L,P<0.01)、BMI(33±5kg/m2vs25±4kg/m2,P<0.05)水平和脂肪百分比(30±8vs20±3,P<0.01)均明显高于G/G基因型者,而血清HDL水平则低于后者(1.08±0.23mmol/Lvs1.38±0.22mmol/L,P<0.01)。G/A型肥胖儿童,除其血清TG浓度高于G/G基因型者外(1.6±0.4mmol/Lvs1.0±0.4mmol/L,P<0.05),余各项指标均与另外两种基因型无明显差别。心电图检查显示部分A/A型血脂增高儿童有ST段和T波改变。结论单纯型肥胖儿童瘦素受体基因第20外显子存在基因多态性,且该多态性明显影响肥胖儿童的脂质代谢及体脂分布。该研究为临床上开展对肥胖儿童的早期干预提供了理论依据。

关键词：瘦素受体多态性,基因脂质代谢肥胖症儿童

Asymmetric Information, Heterogeneous Prior Beliefs and Market Regulation

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 459-476页

作者： hong liu ying JIANG Huai-nian ZHANG KLAS and School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024China Department of Mathematics and Physics Beijing Institute of Petrochemical TechnologyBeijing 102617China

This paper studies the trading behavior of an irrational insider and its influence on the market equilibrium in the presence of market *** find that the market with only one insider with private information is almost close to a strong efficient market,under the condition of market *** the equilibrium,the probability of the insider being caught trading with private information is zero,which shows that the reasonable behavior of the regulator is to essentially give up *** the market efficiency and the irrational trader’s trading intensity all greatly improve because of the existence of the market regulation.

关键词： insider trading market regulation heterogeneous prior beliefs asymmetric information

Dissipative Particle Dynamics Simulations of Domain Growth and Phase Separation in Binary Immiscible Fluids

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Chinese Journal of Chemical Physics 2008年第5期21卷 451-456页

作者： ying Zhao hong liu Zhong-yuan Lu Chia-chung Sun State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryJilin University Changchun 130023 China

It was investigated that the domain growth processes of spinodal decomposition with different quenching depth in two and three dimensional binary immiscible fluids by using parallel dissipative particle dynamics simulations. In two dimensions, the dynamic scaling exponent 1/2 for coalescence and 2/3 for inertial regimes in the shallow quench and strong finite size effects in the cases of deep quenching were obtained. In three dimensions, it was used that the diffusive regime with exponent n=l/3 in the shallow quench and the inertial hydrodynamic regime with n=2/3 for different quenches. The viscous effects are not clearly reflected, showing n=1/2 in both shallow and deep quenches in this time period, due to the soft nature of interaction potential adopted in dissipative particle dynamics.

关键词： Dissipative particle dynamics Binary immiscible fluids Domain growth