|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Artificially triggered lightning and its characteristic discharge parameters in two severe thunderstorms显示文摘The lightning-induced-damages in the mid-latitude regions are usually caused during severe thunder-storms. But the discharge parameters of natural lightning are difficult to be measured. Five lightning flashes have been artificially triggered with the rocket-wire technique during the passage of two severe thunderstorms. The discharge current and close electric field of return stroke in artificially triggered lightning have been obtained in microsecond time resolution by using current measuring systems and electric field change sensors. The results show that the five triggered lightning flashes include 1 to 10 return strokes, and the average return stroke current is 11.9 kA with a maximum of 21.0 kA and a mini-mum of 6.6 kA, similar to the subsequent return strokes in natural lightning. The half peak width of the current waveform is 39 μs, which is much larger than the usual result. The peak current of stroke Ip (kA) and the neutralized charge Q(C) has a relationship of Ip = 18.5Q0.65. The radiation field of return stroke is 5.9 kV·m-1 and 0.39 kV·m-1 at 60 m and 550 m, respectively. The radiation field decreases as r -1.119 with increase of horizontal distance r from the discharge channel. Based on the well-accepted transmission line model, the speed of return stroke is estimated to be about 1.4×108 m·s-1, with a variation range of (1.1―1.6)×108 m·s-1. Because of the similarities of the triggered lightning and natural lightning, the results in this article can be used in the protection design of natural lightning. | QIE XiuShu ZHANG QiLin ZHOU YunJun FENG GuiLi ZHANG TingLong YANG Jing KONG XiangZhen XIAO QingFu WU ShuJun | 2007 | Science China Earth Sciences2007，50，8： | 16 |
| 2 | Minor alloying behavior in bulk metallic glasses and high-entropy alloys显示文摘The effect of minor alloying on several bulk metallic glasses and high-entropy al-loys was studied. It was found that minor Nb addition can optimize the interface structure between the W fiber and the Zr-based bulk metallic glass in the compos-ites,and improve the mechanical properties. Minor Y addition can destabilize the crystalline phases by inducing lattice distortion as a result to improve the glass-forming ability,and the lattice distortion energy is closely related to the effi-ciency of space filling of the competing crystalline phases. A long-period ordered structure can precipitate in the Mg-based bulk metallic glass by yttrium alloying. For the high-entropy alloys,solid solution can be formed by alloying,and its me-chanical properties can be comparable to most of the bulk metallic glasses. | ZHANG Yong ZHOU YunJun HUI XiDong WANG MeiLing CHEN GuoLiang | 2008 | Science China(Physics,Mechanics & Astronomy)2008，51，4： | 10 |
| 3 | Effect of component substitution on the microstructure and mechanical properties of MCoCrFeNiTi_x (M = Cu, Al) solid-solution alloys显示文摘MCoCrFeNiTix (M = Cu, Al; x: molar ratio, x = 0, 0.5) alloys were prepared using the new alloy-design strategy of equal-atomic ratio and high entropy. By the component substitution of Al for Cu, the microstructure changes from the face-centered cubic solid solution of original CuCoCrFeNiTix alloys to the body-centered cubic solid solution of AlCoCrFeNiTix alloys. Compared with original CuCoCrFeNiTix alloys, AlCoCrFeNiTix alloys keep the similar good ductility and simultaneously possess a much higher compressive strength, which are even supe- rior to most of the reported high-strength alloys like bulk metallic glasses. | ZHOU Yunjun ZHANG Yong WANG Xuefei WANG Yanli CHEN Guoliang | 2008 | Rare Metals2008，27，6： | 5 |
| 4 | A Review of Atmospheric Electricity Research in China显示文摘The importance of atmospheric electricity research has been increasingly recognized in recent decades. Research on atmospheric electricity has been actively conducted since the 1980 s in China. Lightning physics and its effects, as important branches of atmospheric electricity, have received more attention because of their significance both in scientific research and lightning protection applications. This paper reviews atmospheric electricity research based primarily on ground-based field experiments at different regions in China in the last decade. The results described in this review include physics and effects of lightning, rocket-triggered lightning and its physical processes of discharge, thunderstorm electricity on the Tibetan Plateau and its surrounding areas, lightning activity associated with severe convective storms, the effect and response of lightning to climate change, numerical simulation of thunderstorm electrification and lightning discharge, lightning detection and location techniques, and transient luminous events above thunderstorms. | QIE Xiushu ZHANG Yijun YUAN Tie ZHANG Qilin ZHANG Tinglong ZHU Baoyou LU Weitao MA Ming YANG Jing ZHOU Yunjun FENG Guili | 2015 | Advances in Atmospheric Sciences2015，32，2： | 5 |
| 5 | Methods of Studying Petroleum Systems in Residual Basins-A Case Study of Mesozoic and Palaeozoic MarineBasins in Southern China显示文摘 | ZHAO Zongju, ZHU Yan, YANG Shufeng, WANG Genghai,XU Yunjun, FENG Jialiang and DENG Hongying Department of Geoscience, Zhejiang University, Hangzhou 310027, Zhejiang Hangzhou Institute of Petroleum Geology, Hangzhou 310023, Zhejiang Zhou Jian Fei Zhenbi | 2002 | Acta Geologica Sinica(English Edition)2002，76，2： | 4 |
| 6 | Lack of evolutionary changes identified in SARS-CoV-2 for the re-emerging outbreak of COVID-19 in Beijing,China显示文摘Although significant achievements have shown that the coronavirus disease 2019(COVID‐19)resurgence in Beijing,China,was initiated by contaminated frozen products and transported via cold chain transportation,international travelers with asymptomatic symptoms or false‐negative nucleic acid may have another possible transmission mode that spread the virus to Beijing.One of the key differences between these two assumptions was whether the virus actively replicated since,so far,no reports showed viruses could stop evolution in alive hosts.We studied severe acute respiratory syndrome coronavirus 2(SARS‐CoV‐2)sequences in this outbreak by a modified leaf‐dating method with the Bayes factor.The numbers of single nucleotide variants(SNVs)found in SARS‐CoV‐2 sequences were significantly lower than those called from B.1.1 records collected at the matching time worldwide(P=0.047).In addition,results of the leaf‐dating method showed ages of viruses sampled from this outbreak were earlier than their recorded dates of collection(Bayes factors>10),while control sequences(selected randomly with ten replicates)showed no differences in their collection dates(Bayes factors<10).Our results which indicated that the re‐emergence of SARS‐CoV‐2 in Beijing in June 2020 was caused by a virus that exhibited a lack of evolutionary changes compared to viruses collected at the corresponding time,provided evolutionary evidence to the contaminated imported frozen food should be responsible for the reappearance of COVID‐19 cases in Beijing.The method developed here might also be helpful to provide the very first clues for potential sources of COVID‐19 cases in the future. | Yang Li Yunjun Zhang Mifang Liang Yi Zhang Xuejun Maa Yong Zhang Xiaohua Zhou | 2022 | Biosafety and Health2022，4，1： | 1 |
| 7 | MODIS -driven estimation of terrestrial latent heat flux in China based on a modified Priestley–Taylor algorithm显示文摘 | Yunjun Yao Shunlin Liang Jie Cheng Shaomin Liu Joshua B. Fisher Xudong Zhang Kun Jia Xiang Zhao Qiming Qin Bin Zhao Shijie Han Guangsheng Zhou Guoyi Zhou Yuelin Li Shaohua Zhao | 2012 | Agricultural and Forest Meteorology2012，，： | 1 |
| 8 | Solid solution alloys of AlCoCrFeNiTix with excellent room-tem-perature mechanical properties显示文摘 | Zhou Yunjun Zhang Yong Wang Yinli | | 0，，18： | 1 |
| 9 | Equation of state of fluid helium at high temperatures and densities显示文摘Hugoniot curves and shock temperatures of gas helium with initial temperature 293 K and three initial pressures 0.6, 1.2, and 5.0 MPa were measured up to 15000 K using a two-stage light-gas gun and transient radiation pyrometer. It was found that the calculated Hugoniot EOS of gas helium at the same initial pressure using Saha equation with Debye-Hückel correction was in good agreement with the experimental data. The curve of the calculated shock wave velocity with the particle velocity of gas helium which is shocked from the initial pressure 5 MPa and temperature 293 K, i.e., the D^u relation, D = C0+λu (u < 10 km/s, λ = 1.32) in a low pressure region, is approximately parallel with the fitted D^u (λ = 1.36) of liquid helium from the experimental data of Nellis et al. Our calculations show that the Hugoniot parameter λ is independent of the initial density ρ0. The D^u curves of gas helium will transfer to another one and approach a limiting value of compression when their temperature elevates to about 18000 K and the ionization degree of the shocked gas helium reaches 10-3. | CAI Lingcang CHEN Qifeng GU Yunjun ZHANG Ying ZHOU Xianming JING Fuqian | 2005 | Science China(Physics,Mechanics & Astronomy)2005，48，6： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员