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秦岭山脉南北麓暴雨触发条件对比分析

高原气象 2025年第1期44卷 178-190页

作者：武麦凤乔舒婷郭大梅任小同渭南市气象局陕西渭南714000 陕西省气象台陕西西安710014

采用实况气象观测资料、FY-2G卫星云图资料、多普勒雷达资料和ERA50.25°×0.25°逐小时再分析资料,对2021年8月21-22日同时发生在秦岭南北麓的强等级暴雨过程进行对比分析,探讨秦岭南北麓暴雨触发条件的影响机制。结果表明:秦岭北麓流... 详细信息

采用实况气象观测资料、FY-2G卫星云图资料、多普勒雷达资料和ERA50.25°×0.25°逐小时再分析资料,对2021年8月21-22日同时发生在秦岭南北麓的强等级暴雨过程进行对比分析,探讨秦岭南北麓暴雨触发条件的影响机制。结果表明:秦岭北麓流场上,西风带系统在秦岭特殊地形作用下,对流层低层形成中尺度气旋性环流,通过热力作用触发暴雨,对流性降水持续时间短,强度小;湿斜压性增强是秦岭北麓暴雨开始的一个信号,当湿斜压性减弱以及中层比湿减小时,降水结束。对秦岭南麓而言,地形作用下对流层低层流场形成中尺度辐合线触发暴雨;降水释放的凝结潜热加热低层大气,与中低层入侵的冷空气共同构建对流不稳定结构,上升运动增强,降水增强和持续;对流云团在高温高湿的环境下迅速组织化合并发展,形成中尺度对流复合体(mCC),对流强度大,对流层结深厚,小时雨强大;中低层冷空气的入侵和扩散到地面的时间分别与秦岭南麓强降水的开始和结束时间对应。

关键词：秦岭地形暴雨动力作用热力作用

DAO媒介:驱动未来社会算法化与自组织的元媒介

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 132-141页

作者：喻国明苏健威北京师范大学新闻传播学院北京师范大学传播创新与未来媒体实验平台北京100875

DAO媒介是以区块链算法等技术为基础,支持数字社群协同自治的媒介,具有区块链、智能合约与投票等功能特性和要素确权、技术信任、规则构架以及场景聚合等价值禀赋。对于数字生态显露的各种问题,“算法化”是重构数字生态、降解社会系统... 详细信息

DAO媒介是以区块链算法等技术为基础,支持数字社群协同自治的媒介,具有区块链、智能合约与投票等功能特性和要素确权、技术信任、规则构架以及场景聚合等价值禀赋。对于数字生态显露的各种问题,“算法化”是重构数字生态、降解社会系统复杂性的关键机制,DAO媒介是支撑“自组织式”算法化的元媒介。DAO媒介与数字文明时代喷发的微粒个体、微资源、微价值、微需求、微场景等相匹配,能够深度匹配人的个性与自我,形成有效的趣缘连接,进而极大地释放数字文明的生产力。DAO媒介将深刻影响社会系统的构造,将微粒个体与相关社会要素“包裹”为闭环子系统,支持其准开放的系统边界、有效的异质性整合、可持续的规则重构、子系统与父级系统的持续分化和快速进化,等等。在数字文明时代,DAO媒介将使“重新部落化”的“地球村”变为现实,其驱动构筑的DAO社会将更加多元、更加富有创造力,不断拓展人类群体实践的自由度,使人类在高度异质性聚合基础上更加和谐有序地整合协同。

关键词： DAO 数字媒介算法自组织社会系统

Correlation between Porosity and Fracture mechanism in High Pressure Die Casting of Am60B Alloy

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journal of materials Science & Technology 2016年第1期32卷 54-61页

作者： X.Li S.m.Xiong Z.guo School of materials Science and Engineering Tsinghua University State Key Laboratory of Automobile Safety and Energy Tsinghua University

X-ray tomography was used to characterize the porosity in high pressure die casting of Am60B alloy. In situ tensile deformation was performed to observe the change of porosities and their influences on crack initiation, propagation and subsequent fracture of specimen. Results showed that four types of porosi- ties, including gas-shrinkage pore, gas pore, net-shrinkage and island-shrinkage, could be identified according to the formation mechanism and morphology characterization. During tensile deformation, it was shown that the gas-shrinkage pore and net-shrinkage, rather than gas pore or island-shrinkage, were the main sources for crack initiation. In addition, the crack propagated by interconnecting the po- rosities at the cross section with minimum efficient force bearing area. At these locations where externally solidified crystals （ESCs） were present, the crack would propagate along the ESC boundaries in an inter- granular mode, while at these locations without ESCs, the crack would propagate roughly along the direction perpendicular to the tensile stress in a combination of trans-granular and inter-granular modes.

关键词： High pressures die casting Am60B alloy Fracture mechanism Porosity

ImPROVEmENT OF DISPERSION ABILITY OF NANOmETER PARTICLES BY mEANS OF PLASmA POLYmERIZATION

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Acta metallurgica Sinica(English Letters) 2002年第1期15卷 73-76页

作者： G.Q. Zhang X.G. guo Y.m. Liu Y.j. Ge Beijing Inst. of Printing Beijing 102600 China

In order to find a new way to improve the dispersion ability of nanometer material, an investigation on preparation of thin film with low surface energy on the surface of nanometer material by means of plasma polymerization has been done. Some physical behaviors and chemical constitution of prepared film as well as the influence of polymerized film on nanometer material were tested. All the experimental results showed that this is a possible way to improve the dispersion ability of nanometer materials.

关键词： plasma polymerization nanometer material

ANTImONY GRAIN BOUNDARY SEGREGATION AND ITS SUPPRESSION BY CERIUm IN Fe-2%mn-Sb STRUCTURAL STEELS

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Acta metallurgica Sinica(English Letters) 2003年第3期16卷 175-182页

作者： Z.X.Yuan A.m.guo j.Liu D.D.Shen j.jia S.H.Song School of materials and metallurgy Wuhan University of Science and Technology Wuhan 430081 China Research Institute of Wuhan Iron and Steel Company Wuhan 430080 China materials Group Department of Mechanical EngineeringBrunel Uliversity Uxbridge Middlesex UBS 3PHUK

Antimony grain boundary segregation in Fe-2%mn-Sb structure steels has been studied through measurements of the ductile-brittle transition temperature in conjunction with scanning electron microscopy, Auger electron spectroscopy and secondary ion mass spectroscopy. The research result reveals that during tempering or ageing after quenching at 980℃, Sb segregates to grain boundaries with both equilibrium and non-equilibrium natures and brings about temper embrittlement in the steels. Cerium can relieve temper embrittlement of the steels and its segregation to grain boundaries may play an important role in reducing this embrittlement.

关键词： segregation grain boundary rare-earth embrittlement

An　Oligomer　Approach　to　Geometry　Optimization　for　Two　Dimensional　Periodic　Polymers

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Chinese Chemical Letters 1996年第9期7卷 859-861页

作者： guo, HY Wang, P Li, j Burke, LA BEIjING UNIV CHEm TECHNOL DEPT APPL CHEMBEIJING 100029PEOPLES R CHINA RUTGERS STATE UNIV DEPT CHEMCAMDENNJ 08102

The oligomer approach used in geometry optimization for two dimensional polymers and crystals has been *** optimization for Planar π-conjugated systems,graphite,with the oligomer approach has been performed at Am1 le... 详细信息

关键词： Optimization Two Dimensional Approach An

Utility of semivariogram for spatial variation of soil nutrients and the robust analysis of semivariogram

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journal of Environmental Sciences 2001年第4期13卷 453-458页

作者： guo, X.-d. Fu, B.-j. ma, K.-m. Chen, L.-d. Department of Systems Ecology Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial variation of soil nutrients in topsoil (0-20cm) was analyzed using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with randomly deleted data and kriged estimates using various reduced sample sizes was also analyzed. The semivariograms of available N, total N, available P, organic matter were best described by a spherical model, except for available K, which best fitted a complex structure of exponential model and linear with sill model. The ratio of nugget to total sample variance ranged from 34.4% to 68.4%, indicating the spatial correlation of tested soil nutrients on a large scale was moderately dependent. Among five soil nutrients, available nitrogen and available phosphorus had the shortest spatial correlation range (5 km and 5.5 km), available K had the longest range (25.5 km), whereas total nitrogen and organic matter had intermediate spatial correlation range (14.5 km and 8.5 km). The semivariograms of available N, total N, available P, and organic matter were insensitive to a 50%-60% reduction in original sampling density, while for available K, it is up to 70%. The estimated spatial distributions of total N by kriging, under various reduced sample sizes, all correlated significantly (P = 0.001) with those obtained from original data. The results showed that the semivariogram was a relatively robust tool when used in a large region and sufficient spatial variation information could be relained regardless of a higher deletion proportion of the original data. The original sample data could be reduced by kriging and the estimates showed no loss of spatial information, however, the results may be unreliable unless a clearly identified semivariogram model could be obtained. The results may provide useful information for determining the appropriate sampling densities for these scales of soil survey.

关键词： Correlation methods Data reduction Nitrogen Phosphorus Sampling Soils Surveying

Generalization of Solovev's approach to finding equilibrium solutions for axisymmetric plasmas with flow

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Plasma Science and Technology 2018年第3期20卷 19-32页

作者： m S CHU Yemin HU Wenfeng guo Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People's Republic of China Center for magnetic Fusion Theory Chinese Academy of SciencesHefei 230031People's Republic of China

Solovev's approach of finding equilibrium solutions was found to be extremely useful for generating a library of linear-superposable equilibria for the purpose of shaping *** set of solutions was subsequently expanded to include the vacuum solutions of Zheng,Wootton and Solano,resulting in a set of functions{SOLOVEV_ZWS}that were usually used for all toroidally symmetric plasmas,commonly recognized as being able to accommodate any desired plasma shapes(complete-shaping capability).The possibility of extending the Solovev approach to toroidal equilibria with a general plasma flow is examined *** found that the only meaningful extension is to plasmas with a pure toroidal rotation and with a constant mach *** also show that the simplification ansatz made to the current profiles,which was the basis of the Solovev approach,should be applied more systematically to include an internal boundary condition at the magnetic axis;resulting in a modified and more useful set{SOLOVEV_ZWSm}.Explicit expressions of functions in this set are given for equilibria with a quasi-constant current density profile,with a toroidal flow at a constant mach number and with specific heat capacity *** properties of{SOLOVEV_ZWSm}are studied *** examples of achievable equilibria are *** the shaping capability of the set{SOLOVE_ZWSm}is quite extensive,it nevertheless still does not have complete shaping capability,particularly for plasmas with negative curvature points on the plasma boundary such as the doublets or indented bean shaped tokamaks.

关键词： theory plasma equilibrium plasma flow

Influence of(FeO+Ti O_2) abundance on the microwave thermal emissions of lunar regolith

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Science China Earth Sciences 2016年第7期59卷 1498-1507页

作者： mENG Zhi guo YANG guo Dong PING jin Song CAI Zhan Chuan Alexander GUSEV Edward m.OSEI College of Geoexploration Science and Technology Jilin University Key Laboratory of Planetary Sciences Chinese Academy of Sciences Key Laboratory of Lunar and Planetary Exploration Chinese Academy of Sciences Faculty of Information Technology Macao University of Science and Technology Institute of Geology Kazan Federal University Department of Geomatic Engineering Kwame Nkrumah University of Science and Technology

One of the essential controls on the microwave thermal emissions(mTE) of the lunar regolith is the abundance of Fe O and TiO_2, known as the(Fe O+Ti O_2) abundance(FTA). In this paper, a radiative transfer simulation is employed first to study the change in the brightness temperature(T_B) with FTA under a range of frequencies and surface temperatures. Then, we analyze the influence of FTA on the mTE of the lunar regolith using microwave sounder(CELmS) data from the Chang'E-2 lunar orbiter, Clementine UV-VIS data, and lunar samples recovered from the Apollo and Surveyor projects. We conclude that:(1) FTA strongly influences the mTE of the lunar regolith, but it is not the decisive control, and(2) FTA decreases slightly with depth. This research plays an essential role in appropriately inverting CELmS data to obtain lunar regolith parameters.

关键词： Lunar regolith microwave thermal emission Radiative transfer simulation (FeO+TiO2) abundance CELmS data