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糖皮质激素在儿科疾病中的应用现状及合理性分析

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中国医院药学杂志 2015年第5期35卷 440-443页

作者：姜哲钟爱娇延边大学附属医院药学部吉林延吉33000 延边大学药学院吉林延吉33000

目的：分析儿科疾病中糖皮质激素应用现状及合理性,为临床合理用药提供参考。方法：对某院2013年1-6月儿科1042份住院病例进行总结,分析糖皮质激素在儿科疾病中的应用情况,利用Excel软件统计相关指标。结果：使用糖皮质激素的病例462份... 详细信息

目的：分析儿科疾病中糖皮质激素应用现状及合理性,为临床合理用药提供参考。方法：对某院2013年1-6月儿科1042份住院病例进行总结,分析糖皮质激素在儿科疾病中的应用情况,利用Excel软件统计相关指标。结果：使用糖皮质激素的病例462份,占总数的44.3%,其中82.3%的患儿集中在0-3周岁;应用合理的病历316份,合格率68.4%,不合理病历主要为选药、给药剂量与时程不合理。结论：糖皮质激素在该院儿科疾病中用药原则、剂量和时程的选择上仍存在一定问题,遵循糖皮质激素合理应用的原则、加强临床药学工作将有助于提高糖皮质激素用药合理性。

关键词：糖皮质激素儿科合理用药

A Provable Positivity-Preserving Local Discontinuous Galerkin Method for the Viscous and Resistive MHD Equations

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Communications on Applied Mathematics and Computation 2024年第1期6卷 279-310页

作者： Mengjiao jiao Yan Jiang Mengping Zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026AnhuiChina

In this paper,we construct a high-order discontinuous Galerkin(DG)method which can preserve the positivity of the density and the pressure for the viscous and resistive magnetohydrodynamics(VRMHD).To control the divergence error in the magnetic field,both the local divergence-free basis and the Godunov source term would be employed for the multi-dimensional *** theoretical analyses are presented for one-dimensional and multi-dimensional DG schemes,respectively,showing that the scheme can maintain the positivity-preserving(PP)property under some CFL conditions when combined with the strong-stability-preserving time ***,general frameworks are established to construct the PP limiter for arbitrary order of accuracy DG *** tests demonstrate the effectiveness of the proposed schemes.

关键词： Viscous and resistive MHD equations Positivity-preserving Discontinuous Galerkin(DG)method High order accuracy

Non-symmetric differentially subordinate martingales and sharp weak-type bounds for Fourier multipliers

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Science China Mathematics 2024年第8期67卷 1807-1826页

作者： Meryem Akboudj Yong jiao Adam Osękowski School of Mathematics and Statistics Hunan Key Laboratory of Analytical Mathematics and ApplicationsCentral South UniversityChangsha 410075China Faculty of Mathematics Informatics and MechanicsUniversity of WarsawWarsaw 02-097Poland

Let p>2 be a given *** this paper,we prove,with the best constant,the weak-type(p,p)inequality■for a large class of non-symmetric Fourier multipliers T_(m) obtained via modulation of jumps of certain Lévy *** particular,the estimate holds for appropriate linear combinations of second-order Riesz transforms and skew versions of the Beurling-Ahlfors operator on the complex *** proof rests on a novel probabilistic bound for Hilbert-space-valued martingales satisfying a certain non-symmetric subordination *** applications to harmonic functions and Riesz systems on Euclidean domains are indicated.

关键词： weak-type bound Fourier multiplier martingale differential subordination laminate

Energy budget of cold and hot gas-solid fluidized beds through CFD-DEM simulations

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Particuology 2024年第6期89卷 153-171页

作者： Lei Bi Yunpeng jiao Chunjiang Liu Jianhua Chen Wei Ge School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Direct energy budget is carried out for both cold and hot flow in gas–solid fluidization ***,the energy paths are proposed from thermodynamic *** consumption means total power input to the specific system,and it can be decomposed into energy retention and energy *** retention is the variation of accumulated mechanical energy in the system,and energy dissipation is the energy converted to heat by irreversible *** based on the Computational Fluid Dynamics-Discrete Element Method(CFD-DEM)framework,different energy terms are quantified from the specific flow elements of fluid cells and particles as well as their interactions with the *** order to clarify the energy budget,it is important to identify which system is studied:the particle-fluid system or the particle *** the cold flow,the total energy consumption of the particle sub-system can well indicate the onset of bubbling and turbulent,while the variation of local energy consumption terms can reflect the evolution of heterogeneous *** the hot flow,different heat transfer mechanisms are analyzed and the solver is modified to reproduce the experimental *** impact of the heat transfer mechanisms and heat production on energy consumption is also *** proposed budget method has proven to be energy-conservative and easy to conduct,and it is hopeful to be applied to other multiphase flow systems.

关键词： Energy budget Gas-solid fluidization CFD-DEM Regime transition Heat transfer mechanism

Quaternary Activity Characteristics and Regional Tectonic Significance of the Jiulong Fault in Jiujiang,Jiangxi Province,China

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Journal of Earth Science 2024年第4期35卷 1107-1117页

作者： Xin Qi Yuyong jiao Qinghua Li Bin Li Faculty of Engineering China University of GeosciencesWuhan430074China Wuhan Center China Geological SurveyWuhan430205China Institute of Geological Survey China University of GeosciencesWuhan430074China

Obtaining geological and landform dislocation features,as well as the measured stratigraphic activity age,provides direct evidence to evaluate fault activity,which is more difficult to do in areas with low tectonic activity,such as eastern and central China.A detailed investigation of the fault activity,trenching,drilling joint geological profile,geological survey,and chronological analysis were used to obtain the spatial geometry,fault kinematics,and activity chronology of the Jiulong *** conclusions are as follows:(1)The Jiulong fault was a fracture zone composed of four branch faults,with a width of around 30–40 m and good extendibility,while the maximum surface rupture length was 373 m.(2)The Jiulong fault has many strata dislocations,and the dislocation distance decreased from bottom to top,demonstrating synsedimentary structure characteristics,with a maximum stratigraphic dislocation distance of 18.2 m.(3)Preliminary analysis suggested the Jiulong fault as a secondary fracture of the Xiangfan-Guangji fault zone and provided evidence of the southeastward extension of the Xiangfan-Guangji fault.A preliminary hypothesis purported the Xiangfan-Guangji fault as the seismogenic fault of the Ms 5.0 magnitude earthquake in 1911.(4)According to OSL and ESR dating analyses,the upper breakpoint of the Jiulong fault cuts into the Late Pleistocene Xingang Formation(Qp3x)strata,and the latest active age of the Jiulong fault was 57.6 *** chronology analysis confirmed an active fault from the Late Pleistocene and identified a weak tectonic in Jiujiang Province,which represents the largest active fault outcrop uncovered in the area so *** study provides evidence and research materials for the evaluation of fault activity and seismic stability in this region.

关键词： active fault regional tectonic earthquakes seismic intensity tectonics

Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

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Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-Wen Shen Chang-Xian Zhao Hao Zhao Shuo-Fei Dong Qi Guo jiao-jiao Xie Mei-Ling Lv Chun-Gang Yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric *** this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample *** compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also *** results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest *** actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward *** was the main exposure pathway for REEs in PM_(2.5)for both children and *** contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and *** exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great *** was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

Prediction of undeformed chip thickness distribution and surface roughness in ultrasonic vibration grinding of inner hole of bearings

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 311-323页

作者： Yanqin LI Daohui XIANG Guofu GAO Feng jiao Bo ZHAO School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

Ultrasonic vibration grinding differs from traditional grinding in terms of its material removal *** randomness of grain-workpiece interaction in ultrasonic vibration grinding can produce variable chips and impact the surface roughness of ***,previous studies used iterative method to calculate the unformed chip thickness(UCT),which has low computational *** this study,a symbolic difference method is proposed to calculate the *** UCT distributions are obtained to describe the stochastic interaction characteristics of ultrasonic grinding ***,the UCT distribution characteristics under different machining parameters are ***,a surface roughness prediction model is established based on the UCT ***,the correctness of the model is verified by *** study provides a quick and accurate method for predicting surface roughness in longitudinal ultrasonic vibration grinding.

关键词： Ultrasonic vibration grinding Undeformed chip thickness(UCT) Distribution characteristics Surface roughness

高水头小流量电站箱式半压力消能工的试验研究

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水利水电技术 2006年第8期37卷 104-107页

作者：焦爱萍邢广彦北京航空航天大学北京100083 黄河水利职业技术学院河南开封475001

利用灌溉供水渠道水流发电的电站,一般在压力管道尾部设岔管分流,经消能后向下游供水。沙沟水电站受地形条件限制,采用常规的消能方式满足不了要求,故采用箱式半压力消能工。由于小流量高水头电站采用箱式半压力消能工的设计尚未有成熟... 详细信息

利用灌溉供水渠道水流发电的电站,一般在压力管道尾部设岔管分流,经消能后向下游供水。沙沟水电站受地形条件限制,采用常规的消能方式满足不了要求,故采用箱式半压力消能工。由于小流量高水头电站采用箱式半压力消能工的设计尚未有成熟的经验,因此必须通过水工物理模型试验,了解通过不同泄量时消能工内的流态、水位和波浪的变化,观察水流的掺气和波动情况,以确定箱式半压力消能工的合理尺寸。

关键词：高水头小流量电站箱式半压力消能工物理模型试验沙沟水电站

Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station

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Astrodynamics 2024年第1期8卷 77-95页

作者： Hao Zhou Bohan jiao Zhaohui Dang Jianping Yuan School of Astronautics Northwestern Polytechnical UniversityXi’an710072China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an710072China

This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple ***,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and ***,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance ***,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s *** closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning ***,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation *** simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites.

关键词： China Space Station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system