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甘肃平凉市的旅游气候舒适度评价

干旱气象 2013年第4期31卷 684-689页

作者：党冰王式功尚可政兰州大学大气科学学院甘肃省干旱气候变化与减灾重点实验室甘肃兰州730000

利用甘肃省平凉市7县（区）气象观测站1961—2010年50a气象资料，采用温湿指数、风寒指数和着衣指数指标，对平凉7县（区）各月旅游气候舒适度进行了分析。结果显示，平凉市7县（区）旅游气候最舒适期为每年的5～9月，较舒适期在4月和1... 详细信息

利用甘肃省平凉市7县（区）气象观测站1961—2010年50a气象资料，采用温湿指数、风寒指数和着衣指数指标，对平凉7县（区）各月旅游气候舒适度进行了分析。结果显示，平凉市7县（区）旅游气候最舒适期为每年的5～9月，较舒适期在4月和10月，不舒适期静宁、庄浪、华亭为4个月，主要分布在冬季及秋末（1～2月、11—12月），崆峒、灵台、泾川、崇信为3个月，分布在冬季的1、2、12月。由于地理位置和海拔高度的不同，平凉旅游气候在东西南北方向上有着一定差异，在东西方向上差异尤其明显，一年中舒适度年指数自西向东呈升高趋势。

关键词：平凉崆峒山气候舒适指数评价

Study of Seismic P Wave in Mesoscale Fracture-Induced Arbitrary Anisotropic Media

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Journal of Earth Science 2024年第2期35卷 717-721页

作者： Han Xiao Xinmin shang Zhentao Wang Xiping Wang Geophysical Research Institute SINOPEC Shengli Oilfield CompanyShandong 257022China Working Station for Postdoctoral Scientific Research Shengli OilfieldShandong 257000China

Mesoscale fracture controls the permeability of shale res ervoirs,it is one of the main research objectives of natural frac *** length of the mesoscale fracture is less than 1/4 of the seismic eigen wavelength and greater than 1%of the seis mic eigen wavelength,they cannot be identified in actual seis mic data and are usually displayed by the azimuthal anisotropy of seismic *** this paper,we propose a calculation process from fracture properties to seismic P-wave velocity and traveltime in anisotropic media induced by multiple sets of arbitrary occurring mesoscale *** on this process,the variations of the media’s Anisotropic(A-)parameters with fracture properties are ***,variation of P-wave NMO elliptical principle axis with the relative fracture density is studied according to the arbitrary anisotropic theory based on A-parameters.

关键词： seismic mesoscale shale

The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang HUANG Weidong SUN Xing DING Yusheng ZHAO Yibing LI Xiuqi shang CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction *** is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly *** this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal *** experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and *** proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy *** 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much *** overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+*** the addition of more silica(20 wt%and 40 wt%),olivine was transformed into *** rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same *** overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=*** experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal *** 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen *** on measured H_(2),we calibrated ox

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

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冷空气大风过程中动量下传特征

中国沙漠 2016年第2期36卷 467-473页

作者：邬仲勋王式功尚可政杨子凡陈锋兰州大学大气科学学院甘肃兰州730000 酒泉卫星发射中心甘肃酒泉732750

利用NCEP再分析资料,对中国西北地区一次大范围冷空气大风过程中的动量下传特征进行了分析。结果表明:动量下传大风是高低空风场辐合辐散的环流运动强迫所造成的大风,发生的区域一般在高空急流南部整层垂直速度接近零的地方;动量下传大... 详细信息

利用NCEP再分析资料,对中国西北地区一次大范围冷空气大风过程中的动量下传特征进行了分析。结果表明:动量下传大风是高低空风场辐合辐散的环流运动强迫所造成的大风,发生的区域一般在高空急流南部整层垂直速度接近零的地方;动量下传大风起风前后,垂直速度在高空急流两侧存在明显的反转,且下沉气流区较早接地,大风风速比冷锋大风略小,但持续时间较长;地面冷锋过境之后,高层高位涡区在高空槽持续影响的情况下有明显的向下传递作用,表示具有高位涡特征大气的侵入;高空槽是造成动量下传的主要原因,高空槽的形状及强度对于预报动量下传大风具有较大的意义,槽过境及槽后强西北气流可造成大风的持续。

关键词：大风个例分析动量下传

Freestanding MoSe_(2)nanoflowers for superior Li/Na storage properties

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Tungsten 2024年第1期6卷 238-247页

作者： Qiao Cu Chao-Qun shang Guo-Fu Zhou Xin Wang Guangdong Provincial Key Laboratory of Optical Information Materials South China Normal UniversityGuangzhou 510006China School of Materials Science and Engineering and Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China International Academy of Optoelectronics at Zhaoqing South China Normal UniversityZhaoqing 526060China

MoSe_(2),with high theoretical specific capacity,has attracted a lot of *** remains an open challenge to effectively suppress the irreversible selenium dissolution and rapid capacity decrease induced by severe volume change during ***,we synthesize MoSe_(2)nanoflowers dispersed on one-dimensional(1D)N-doped carbon nanofibers(MoSe_(2)@NCNFs)for use as a freestanding *** this unique structure,the 1D N-doped carbon nanofibers are found to not only enhance the conductivity but also ensure the structural integrity during the Li^(+)/Na^(+)insertion/destraction *** expected,at 2 A·g^(-1),the specific capacity of the MoSe_(2)@NCNFs is maintained at 180 mAh·g^(-1)after 500 cycles when used in lithium storage ***,in the case of sodium storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capacity of 122mAh·g^(-1)after 500 *** findings suggest that the MoSe_(2)@NCNF electrodes may be a promising candidate for use in reversible Li/Na storage applications.

关键词： Li/Na storage Freestanding electrode MoSe_(2) Electrochemical reaction kinetics Structural integrity

2008—2013年库姆塔格沙漠及阿尔金山降水特征

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中国沙漠 2015年第1期35卷 203-210页

作者：康延臻陈世红张莹王式功尚可政程一帆兰州大学大气科学学院甘肃兰州730000 兰州大学甘肃省干旱气候变化与减灾重点实验室甘肃兰州730000 兰州大学资产与实验室管理处甘肃兰州730000

库姆塔格沙漠极端干旱,而其南部阿尔金山比较湿润。研究库姆塔格沙漠及南部阿尔金山的降水特征,对揭示库姆塔格沙漠水源补给机制和地貌形成原因具有重要作用。本文利用中国自动气象站与CMORPH融合逐时降水量0.1°网格数据集,分析了库姆... 详细信息

库姆塔格沙漠极端干旱,而其南部阿尔金山比较湿润。研究库姆塔格沙漠及南部阿尔金山的降水特征,对揭示库姆塔格沙漠水源补给机制和地貌形成原因具有重要作用。本文利用中国自动气象站与CMORPH融合逐时降水量0.1°网格数据集,分析了库姆塔格沙漠及阿尔金山的降水特征。结果表明:(1)库姆塔格沙漠降水主要集中在夏季,其他季节降水较少;而阿尔金山降水主要集中在春、秋两季,并存在一条降水量大值带,3月范围最大而夏季消失;(2)阿尔金山对库姆塔格沙漠的水源补给作用主要体现在春、秋两季,夏季降水基本与库姆塔格沙漠持平,春季降水超出库姆塔格沙漠最多;(3)阿尔金山各月平均逐小时降水量演变特征有很大不同,冬季12、1月及夏季6、7月每月逐时降水演变特征以"凌晨型"为主,可能与凌晨云顶辐射冷却引起的大气层结不稳定有关;春、秋两季每月逐时降水演变特征以"午后-黄昏型"为主,可能与午后太阳辐射地面加热引起的大气层结不稳定有关;2、8月是两种类型的过渡时期。本文研究结果可为探索库姆塔格沙漠水源补给机制以及"羽毛状沙丘"独特的沙漠景观形成原因提供一定的参考依据。

关键词：库姆塔格沙漠阿尔金山降水

Identification of aircraft longitudinal aerodynamic parameters using an online corrective test for wind tunnel virtual flight

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 261-275页

作者： Tai, shang Bu, Chen Wang, Yanling Yue, Ting Liu, Hailiang Wang, Lixin Beihang Univ Sch Aeronaut Sci & Engn Beijing 100191 Peoples R China AVIC Aerodynam Res Inst Harbin 150001 Peoples R China

The identification of aerodynamic parameters is accomplished through the test data of the dynamic movement of scaled aircraft models flying dynamically in wind tunnel, which can realize the accurate acquisition of the aerodynamic model of the aircraft in the preliminary stage for aircraft design, and it is of great significance for improving the efficiency of aircraft design. However, the translational motion of the test model in the wind tunnel virtual flight is subject to constraints that result in distinct flight dynamics compared to free flight. These constraints have implications for the accuracy of aerodynamic derivatives obtained through the identification of wind tunnel test data. With this issue in mind, the research studies the differences in longitudinal dynamic characteristics between unconstrained free flight and wind tunnel virtual flight, and innovatively proposes an online correction test based wind tunnel virtual flight test technique. The longitudinal trajectory and velocity changes of the model are solved online by the aerodynamic forces measured during the test, and then the coupled relationship between aircraft translation and rotation is used to correct the model's pitch attitude motion online. For the first time, the problem of solving the data approximation for free flight has been solved, eliminating the difference between the dynamics of wind tunnel virtual flight and free flight, and improving the accuracy of the aerodynamic derivative identification results. The experiment's findings show that accurate aerodynamic derivatives can be identified based on the online correction test data, and the observed behaviour of the identified motion model has similarities to that of the free flight motion model. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Wind tunnels Displacement constraints Online solution Flight control law Aerodynamic parameter identification MODEL SIMULATION STABILITY MANEUVER DESIGN RIG

Application of Isogeometric Analysis Method in Three-Dimensional Gear Contact Analysis

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 817-846页

作者： Long Chen Yan Yu Yanpeng shang Zhonghou Wang Jing Zhang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai200093China Zhejiang Fine-Motion Robot Joint Technology Co. Ltd.Taizhou317600China

Gears are pivotal in mechanical drives,and gear contact analysis is a typically difficult problem to *** isogeometric analysis(IGA)methods have developed new ideas to solve this *** this paper,a threedimensional body parametric gear model of IGA is established,and a theoretical formula is derived to realize single-tooth contact *** were benchmarked against those obtained from commercial software utilizing the finite element analysis(FEA)method to validate the accuracy of our *** findings indicate that the IGA-based contact algorithmsuccessfullymet theHertz contact *** juxtaposed with the FEA approach,the IGAmethod demonstrated fewer node degrees of freedomand reduced computational units,all whilemaintaining comparable ***,the IGA method appeared to exhibit consistency in analysis accuracy irrespective of computational unit density,and also significantlymitigated non-physical oscillations in contact stress across the tooth *** underscores the prowess of IGA in contact *** conclusion,IGA emerges as a potent tool for addressing contact analysis challenges and holds significant promise for 3D gear modeling,simulation,and optimization of various mechanical components.

关键词： Contact analysis involute gear isogeometric analysis finite element analysis

In-situ measurement via the flow-through method and numerical simulations for radon exhalation during measurements of the radon exhalation rate

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Nuclear Science and Techniques 2024年第7期35卷 192-207页

作者： Ming Xia Yong-Jun Ye Shan-Wei shang Ting Yu Dai-Jia Chen School of Resources Environment and Safety Engineering University of South ChinaHengyang421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang421001China

Small-scale measurements of the radon exhalation rate using the flow-through and closed-loop methods were conducted on the surface of a uranium tailing pond to better understand the differences between the two *** abnormal radon exhalation behavior was observed,leading to computational fluid dynamics(CFD)-based simulations in which dynamic radon migration in a porous medium and accumulation chamber was *** on the in-situ experimental and numerical simulation results,variations in the radon exhalation rate subject to permeability,flow rate,and insertion depth were quantified and *** in-situ radon exhalation rates measured using the flow-through method were higher than those measured using the closed-loop method,which could be explained by the negative pressure difference between the inside and outside of the chamber during the *** consistency of the variations in the radon exhalation rate between the experiments and simulations suggests the reliability of CFD-based techniques in obtaining the dynamic evolution of transient radon exhalation rates for diffusion and convection at the porous medium-air *** synergistic effects of the three factors(insertion depth,flow rate,and permeability)on the negative pressure difference and measured exhalation rate were quantified,and multivariate regression models were established,with positive correlations in most cases;the exhalation rate decreased with increasing insertion depth at a permeability of 1×10^(−11) m^(2).CFD-based simulations can provide theoretical guidance for improving the flow-through method and thus achieve accurate measurements.

关键词： Radon exhalation Flow-through Numerical simulation Accumulation chamber Multivariate regression