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NUMERICAL STUDIES OF PLANETARY BOUNDARY LAYER PARAMETERIZATION SCHEMES ON SUPER TYPHOON SANBA(2012)DURING ITS INITIAL STAGE

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Journal of Tropical Meteorology 2018年第3期24卷 288-299页

作者： wen Xiao-pei LONG Xiao zhang shu-wen LI Dan-hua School of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Shandong Institute of Meteorological Science Ji'nan 250031 China

The formation and development of typhoons are closely related to the disturbed low vortexes at the planetary boundary layer(PBL). The effects of five PBL parameterization schemes(PBL schemes hereinafter) on the trajectory,intensity, and distribution of physical quantities are studied using the mesoscale WRF model on Super Typhoon Sanba(2012) during its initial stage. Results show that the five PBL schemes exhibit significant different effects on the simulated intensity and path. The results simulated by QNSE and ACM2 without the Bogus method are close to the best track data in the numerical experiments. When the Bogus method is adopted, the simulated trajectories improve significantly because the initial field is close to the true data. Among the five PBL schemes, QNSE and ACM2 with the Bogus method present improved simulated path and intensity compared with the three other schemes. This finding indicates that the two schemes deal with the initial PBL process satisfactorily, especially in the formation and development of disturbed low vortexes. The differences in the treatment methods of the five PBL schemes affect the surface layer physical quantities and the middle and upper atmospheres during the middle to late periods of the *** QNSE and ACM2 present better simulation results than other schemes, they exhibit a few differences in the internal structure of the typhoon. The results simulated by MYJ are worse, and this method may be unsuitable for studying the formation and development of typhoons.

关键词： typhoon PBL parameterization schemes the Bogus method initial stage

A COMPARATIVE STUDY OF SPECTRAL METHODS WITH SEA WAVE DATA

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Journal of Hydrodynamics 2000年第4期12卷 59-65页

作者： zhang shu-wen Sun Fu Key Laboratory of Marine Science and Numerical Modeling State Oceanic AdministrationQingdao 266003P.R.China Qingdao University Qingdao 266071P.R.China Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration

Two spectral methods are used to study sea wave data. Firstly, the estimated results calculated by the sequency spectrum method and frequency spectrum method are compared, and then the differences between the two methods are discussed. Furthermore, compared with frequency spectral analysis, sequency spectral analysis has many advantages: faster calculating speed, convenient use and high distinguishability.

关键词： sequency spectrum frequency spectrum sea wave data

Deformation mechanism and hydrocarbon significance of Eocene organic-rich fine-grained soft sediments in the Leijia Region,Liaohe Depression

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Frontiers of Earth Science 2024年第1期18卷 83-97页

作者： Yijie wen Jianguo zhang shu TAO Chenyu CAI School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas(Ministry of Land Resources) China University of Geosciences(Beijing)Beijing 100083China School of Foreign Languages China University of Geosciences(Beijing)Beijing 100083China

The deformation structure of soft sediments has always been a research hotspot,which is of great significance for analyzing the tectonic and sedimentary evolution background of a basin,as well as the physical properties of *** studies have reported that a large number of soft sediment deformation structures are developed in the western part of Liaohe *** this study,through core observation and thin section identification,various types of deformation structures are identified in the core samples which are collected from the upper Es4 in the Leijia region,western sag of Liaohe depression,such as liquefied dikes,liquefied breccia,convoluted laminae,annular bedding,synsedimentary faults,vein structures,*** on the characteristics of core structure,single well profile and continuous well profile,combined with the regional background,this study clarifies that the deformation structure of soft sediments in the study area is mainly caused by seismic *** is found that the permeability and porosity of deformation layers in the study area are higher than those of the undeformation layers,which proves that the deformation structure of soft sediments has a good effect on improving the physical properties of reservoirs.

关键词： soft sediment deformation structure Liaohe depression organic-rich fine-grained soft sediments hydrocarbon significance

Assessment of the effects of the shelterbelt on the soil temperature at regional scale based on MODIS data

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Journal of Forestry Research 2011年第1期22卷 65-70页

作者： DENG Rong-xin LI Ying zhang shu-wen WANG wen-juan SHI Xiao-liang Northeast Institute of Geography and Agriculture Ecology CASChangchun 130012 China. Graduated School of Chinese Academy of Science Beijing 100049China Department of Resources and Environmental Sciences Henan Universityof Finance and Economics Zhengzhou 450002 China

At present, the most researches on the protected effect of shelterbelt are on the basis of the two scales of forest belts and networks. However, with the further research on the global environmental change, more attention was paid to the regional climate effect of shelterbelt. In present study, we analyzed the temperature effect of the shelterbelt at regional scale by using the land surface temperature （LST） data from the moderate resolution imaging spectroradiometer （MODIS） at Yushu, Nong＇an, Dehui, and Fuyu in Jilin Province of China from March to October in 2008. Results show that the shelterbelt can increase the soil temperature of the protected farmland as compared with no shelterbelt zone, with the increment of 0.57oC per day in fine shelterbelt and 0.38oC per day in the normal shelterbelt. Moreover, the correlation analysis of the air temperature, precipitation and the soil type and the shelterbelt effect shows that the air temperature and precipitation are negatively correlated with the shelterbelt effects, that is, the more the temperature and precipitation are, the less the effect produced. While the impact of the soil types on the shelterbelt＇s effect is not very obvious as a whole. This paper draws significance in terms of analyzing the effects of the shelterbelt on the soil temperature at regional scale utilizing the remotely sensed data and GIS technique.

关键词： regional scale remote sensing shelterbelt temperature effect

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孝昌县农药减量工作的现状与建议

湖北植保 2024年第3期 7-8,21页

作者：张树文曾俊赵磊张天悦沈青万荣孝昌县农业技术推广中心湖北孝昌432900 孝感市农业技术推广中心湖北孝感432100

为寻找本地最适合的农药减量路径,孝昌县积极开展了农药减量专题调查。本文分析了孝昌县农药减量的现状和存在的问题,提出了进一步推进农药减量工作的建议,对治理农业面源污染和保障粮食安全有着重要意义。

关键词：农药减量增效绿色防控

Elaborative collection of condensed combustion products of solid propellants:Towards a real Solid Rocket Motor(SRM)operational environment

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Chinese Journal of Aeronautics 2024年第1期37卷 77-88页

作者： wenchao zhang Zhimin FAN Dongliang GOU Yao shu Peijin LIU Aimin PANG wen AO National Key Laboratory of Solid Rocket Propulsion Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Aerospace Chemical Power Laboratory Xiangyang 441003China

A novel constant-pressure and constant-quenching distance Condensed Combustion Products(CCPs)collection system was developed,coupled with a timing control system,to collect the CCPs formed in the course of burning of aluminum-based composite *** effects of adiabatic graphite plating,collection zone,quenching distance,time series of collection,and propellant burning rate on the microscopic morphology,particle size distribution and unburned aluminum content of CCPs were *** was verified that the graphite plating can provide a high-fidelity high-temperature environment for propellant *** combustion efficiency is improved by 2.44% compared to the bare propellant *** time series of collection has a significant effect on the combustion efficiency of aluminum,and the combustion efficiency of aluminum in the thermal state(1.2-2.4 s)is 2.75% higher than that in the cold state(0-1.2 s).Similarly,the characteristics of the CCPs in different collection zones are *** the quenching distance of 5 mm,the combustion efficiency of aluminum in the core zone(85.39%)is much lower than that in the outer zone(92.07%),while the particle size of the CCPs in the core zone(172μm)is larger than that in the outer zone(41μm).This indicates that the core zone is more likely to produce large-sized and incompletely burned agglomerates during the propellant combustion *** burning rates also lead to a significant difference in particle size distribution and combustion *** burning rates result in higher combustion efficiency.A detailed sequence of the elaborative collection process of CCPs is proposed,mainly including the setting of ignition delay time,burning rate,working pressure,plating length and time series of *** findings of this study are expected to provide a reliable tool for the evaluation of the combustion efficiency of solid propellants.

关键词： Composite propellants Condensed combustion products Aluminum Combustion efficiency Particle size distribution

养阴清热法辅助治疗2型糖尿病有效性和安全性的Meta分析

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世界中西医结合杂志 2024年第7期19卷 1312-1325,1329页

作者：蒋一佳张文华尹丹张舒文贾玮钰王楚然费宇彤龚燕冰北京中医药大学东直门医院北京100700 北京中医药大学北京100029

目的系统评价养阴清热法联合常规降糖西药治疗2型糖尿病(Type 2 diabetes mellitus,T2DM)的有效性及安全性。方法计算机检索CNKI、万方、维普、SinoMed、PubMed、Cochrane Library以及Web of Science,检索时限为建库至2022年5月,筛选关... 详细信息

目的系统评价养阴清热法联合常规降糖西药治疗2型糖尿病(Type 2 diabetes mellitus,T2DM)的有效性及安全性。方法计算机检索CNKI、万方、维普、SinoMed、PubMed、Cochrane Library以及Web of Science,检索时限为建库至2022年5月,筛选关于养阴清热法治疗T2DM的临床随机对照试验(Randomized controlled trials,RCTs),其中对照组予常规西医基础治疗,试验组在对照组基础上加用以养阴清热为主要功效的中药或复方,采用Cochrane风险偏倚评估工具进行文献质量评价,使用RevMan 5.4软件进行统计学分析。结果最终纳入40篇RCTs,共计3637例患者。Meta分析结果显示,试验组临床总有效率高于对照组[RR=1.23,95%CI(1.19,1.27),P<0.00001],试验组在降低空腹血糖[MD=-1.17,95%CI(-1.33,-1.01),P<0.00001]、餐后2 h血糖[MD=-1.77,95%CI(-2.10,-1.44),P<0.00001]、糖化血红蛋白[MD=-1.03,95%CI(-1.28,-0.77),P<0.00001]、空腹胰岛素[MD=-3.35,95%CI(-4.01,-2.69),P<0.00001]、胰岛素抵抗指数[MD=-0.66,95%CI(-1.19,-0.13),P=0.01]、肿瘤坏死因子-α[SMD=-3.88,95%CI(-5.74,-2.02),P<0.00001]、白介素-6[SMD=-3.17,95%CI(-4.54,-1.80),P<0.00001]、甘油三酯[MD=-0.51,95%CI(-0.69,-0.33),P<0.00001]、总胆固醇[MD=-0.75,95%CI(-0.99,-0.50),P<0.00001]方面优于对照组。两组不良反应发生率比较,差异有统计学意义[RR=0.52,95%CI(0.36,0.76),P=0.0007]。结论养阴清热法辅助治疗2型糖尿病具有良好临床疗效及一定安全性,但由于纳入研究质量限制,仍需要更多大样本、多中心RCTs以提供更可靠的循证依据。

关键词： 2型糖尿病养阴清热法有效性 Meta分析

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波浪破碎气体的卷入过程及相关统计量的估计

物理学报 2008年第5期57卷 3287-3292页

作者：张书文广东海洋大学南海海洋环境研究所湛江524088

基于实验观测,导出了波浪破碎能量耗散εed、气泡云卷入深度zb、气体卷入速率Q(z)和湍流动能耗散率εT(z)的表达式,在此基础上建立了一种简单、实用的气泡粒径谱参数化模式N(a,z),揭示了波浪破碎气泡云卷入过程能量耗散、气泡破碎临界Hi... 详细信息

基于实验观测,导出了波浪破碎能量耗散εed、气泡云卷入深度zb、气体卷入速率Q(z)和湍流动能耗散率εT(z)的表达式,在此基础上建立了一种简单、实用的气泡粒径谱参数化模式N(a,z),揭示了波浪破碎气泡云卷入过程能量耗散、气泡破碎临界Hinze特征尺度和气泡粒径谱在不同海况下的变化.研究表明:气泡云卷入过程能量耗散率与波浪破碎能量耗散之比在中低风速下介于10%与60%之间,但当风速大于15m/s时,这一比值小于5%.气泡破碎临界Hinze特征尺度,随着风速的增大和波浪的不断成长向低频区移动.气泡粒径谱主要取决于海面气体卷入速率、湍流动量耗散率和破碎面积比,且敏感地依赖于风速和波浪成长状态.

关键词：波浪破碎能量耗散气泡云卷入深度气泡粒径谱

ANALYSIS OF THE EXPANSION OF THE BUILT-UP AREA OF DALIAN CITY

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Chinese Geographical Science 2002年第4期12卷 373-377页

作者： CHANG Li-ping,zhang shu-wen(Changchun Institute of Geography,t he Chinese Academy of Sciences,Changchun 130012,P.R.China) Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

With the astounding development and gradual improvement of remote sensing technology,as an advanced science technology,it is used to pro vide multi-temporal,large scope re al-time information for land-use dynamic change,and also is one of the best efficient m ethods for studying the earth resour ces and *** sensing image has its characteristics of ample inform ation and reflecting the objective r *** paper uses multi-temp oral TM images in1986,1996and 2000,and relevant sta tistic data to analyze land-use chan ges of Dalian City in Liaoning Provin ce of Chi-na over ten years by means of the corre lation analysis *** results have shown that two methods could con-formably reflect the present land-u se *** is closely c orrelative to natural factors and ec onomic *** in recent 20years,under the influence of the reform and open-up policy,Dalian,as a specifi c coast city,is becoming an international m etropolis.

关键词： land-use change remote sensing driving force dalian city