维普中文期刊产品整合服务
8篇 您的检索式:作者名="Ma Penghui"
    题名 作者 年代 出处 被引量
1The Late Carboniferous–Early Permian Ocean-Continent Transition in the West Junggar,Central Asian Orogenic Belt: Constraints from Columnar Jointed Rhyolite显示文摘The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial on the exact time of ocean-continent transition so far. This study investigates rhyolites with columnar joint in the West Junggar for the first time.Based on zircon U-Pb dating, we determined that the ages of the newly-discovered rhyolites are between 303.6 and 294.5 Ma, belonging to Late Carboniferous–Early Permian, which is the oldest rhyolite with columnar joint preserved in the world at present. Geochemical results show that the characteristics of the major element compositions include a high content of SiO_2(75.78–79.20 wt%) and a moderate content of Al_2O_3(12.21–13.19 wt%). The total alkali content(K_2O +Na_2O) is 6.14–8.05 wt%, among which K_2O is 2.09–4.72 wt% and the rate of K_2O/Na_2O is 0.38–3.05. Over-based minerals such as Ne, Lc, and Ac do not appear. The contents of TiO_2(0.09–0.24 wt%), CaO(0.15–0.99 wt%) and MgO(0.06–0.18 wt%) are low. A/CNK=0.91–1.68, A/NK=1.06–1.76, and as such, these are associated with the quasi-aluminum-weak peraluminous high potassium calc-alkaline and some calc-alkaline magma series. These rhyolites show a significant negative Eu anomaly with relative enrichment of LREE and LILE(Rb, Ba, Th, U, K) and depletion of Sr, HREE and HFSE(Nb, Ta, Ti, P). These rhyolites also have the characteristics of an A2-type granite, similar to the Miaoergou batholith,which indicates they both were affected by post-orogenic extension. Combining petrological, zircon U-Pb dating and geochemical characteristics of the rhyolites, we conclude that the specific time of ocean-continent transition of the West Junggar is the Late Carboniferous–Early Permian.XU Shenglin CHEN Xuanhua LI Tingdong SHI Jianjie DING Weicui LI Bing HUANG Penghui ZHANG Yiping ZHANG Yaoyao MA Feizhou 2019Acta Geologica Sinica(English Edition)2019,93,2:9
2Identification of landslide spatial distribution and susceptibility assessment in relation to topography in the Xi'an Region, Shaanxi Province, China显示文摘Jianqi ZHUANG Jianbing PENG Javed IQBAL Tieming LIU Na LIU Yazhe LI Penghui MA 2015Frontiers of Earth Science2015,9,3:4
3Initiation Mechanism of Loess Mudflows by Flume Experiments显示文摘The structure of loess is loose,and the shear strength of loess drops sharply after contact with water.Therefore,loess mudflows have become a common geological disaster on the Chinese Loess Plateau.In order to study the initiation mode and mechanism of loess mudflows,in this study,seven sets of flume experiments were designed by controlling the slope angle and rainfall intensity.The results show that(1)when the slope angle is between 10°and 20°,there are two initiation mechanisms of loess mudflows:mudflow(large scale)and retrogressive toe sliding,and mudflow(small-scale)and retrogressive toe sliding.(2)The main method by which water infiltrates into the soil accumulation is mainly vertical infiltration,which is not affected by the slope angle and the seepage direction of the accumulation soil.(3)The liquefaction of loess is the root cause of loess mudflows.Water infiltrates into the area with an uneven density and a large amount of water accumulates in this area.Thus,the water content of the loess increases and the pore water pressure increases quickly and cannot dissipate in time,so the loess liquefies and the liquefacted area continues to spread and become larger.Thus,loess mudflows(large scale)occur.The increase in pore water pressure was captured in the seven sets of experiments.However,the order of the rising positions in the accumulation were different.This requires us to carry out tracking of the particle displacement inside the soil and the spatial changes in the internal structure of the soil in future research.Penghui Ma Jianbing Peng Jianqi Zhuang Xinghua Zhu Cong Liu Yuxiang Cheng Zuopeng Zhang 2022Journal of Earth Science2022,33,5:1
4A simple solvothermal route to synthesize graphene-modified LiFePO 4 cathode for high power lithium ion batteries显示文摘Yin Zhang Wenchao Wang Penghui Li Yanbao Fu Xiaohua Ma 2012Journal of Power Sources2012,,:1
5Properties and mechanism of ionic liquid/silicone oil based magnetorheological fluids显示文摘A magnetorheological fluid(MRF)is a smart composite suspension composed of nonmagnetic liquid and soft magnetic particles.Carrier fluids can considerably influence the performance of MRFs;therefore,to investigate the effect of carrier fluids on MRFs,an SO/IL-MRF was prepared by mixing an ionic liquid(IL)with silicone oil(SO)in this study.Three types of MRF samples were prepared for experiments(pure SO,pure IL,and SO/IL).According to the experi-mental results,the SO/IL-MRF has better sedimentation stability than those based on pure SO and pure IL.Further,three methods were used to determine the shear yield stresses of the MRFs.The SO/IL-MRF achieved a higher shear yield stress than those of the other two because a network structure is formed between the ionic fragments and the molecular chains of the SO in the SO/IL-MRF.This increases the movement resistance of the particles in the carrier fluid,and it is unlike the mechanism of the IL-enhanced MRF.This work provides new ideas for improving the MRF performance.Yu Tong Penghui Zhao Xiaoguang Li Ning Ma Xufeng Dong Chenguang Niu Zhanjun Wu Min Qi 2022International Journal of Smart and Nano Materials2022,13,2:0
6Hard nanocrystalline gold materials prepared via high-pressure phase transformation显示文摘As one of the important materials,nanocrystalline Au(n-Au)has gained numerous interests in recent decades owing to its unique properties and promising applications.However,most of the current n-Au thin films are supported on substrates,limiting the study on their mechanical properties and applications.Therefore,it is urgently desired to develop a new strategy to prepare nAu materials with superior mechanical strength and hardness.Here,a hard n-Au material with an average grain size of~40 nm is prepared by cold-forging of the unique Au nanoribbons(NRBs)with unconventional 4H phase under high pressure.Systematic characterizations reveal the phase transformation from 4H to face-centered cubic(fcc)phase during the cold compression.Impressively,the compressive yield strength and Vickers hardness(HV)of the prepared n-Au material reach~140.2 MPa and~1.0 GPa,which are 4.2 and 2.2 times of the microcrystalline Au foil,respectively.This work demonstrates that the combination of high-pressure cold-forging and the in-situ 4H-to-fcc phase transformation can effectively inhibit the grain growth in the obtained n-Au materials,leading to the formation of novel hard n-Au materials.Our strategy opens up a new avenue for the preparation of nanocrystalline metals with superior mechanical property.Chenlong Xie Wenxin Niu Penghui Li Yiyao Ge Jiawei Liu Zhanxi Fan Xiaoxiao Liu Ye Chen Ming Zhou Zihe Li Mengdong Ma Yonghai Yue Jing Wang Li Zhu Kun Luo Yang Zhang Yingju Wu Lin Wang Bo Xu Hua Zhang Zhisheng Zhao Yongjun Tian 2022Nano Research2022,15,7:0
7A Comprehensive Method for the Risk Assessment of Ground Fissures:Case Study of the Eastern Weihe Basin显示文摘Ground fissures are influenced by the coupling of geological factors and human activi-ties.They threaten the safety of infrastructure and restrict town planning in many areas in China.One of the area most severely affected by ground fissures is the Weihe Basin in North China,which has the most extensive distribution of ground fissures and all the elements that control their occurrence,pro-viding an ideal study area for the study of ground fissures.In this study,we took the eastern Weihe Ba-sin as the study area and determined the distribution and hazard characteristics of ground fissures via field investigation.Based on the analytic hierarchy process,we propose a multi-level,comprehensive method for evaluating the hazards of ground fissures.This method considers the geological back-ground,development status,and triggering factors of ground fissures,including all nine currently known assessment indices of ground fissures.We used judgment matrices to rank the constructed ground fissure assessment index system at the single and total levels and quantified the nine assessment indices of ground fissures according to the field survey data.Finally,we plotted the ground fissure risk zoning map and evaluated the ground fissure risk at the study area.Our findings indicated that the proposed method could facilitate ground fissure hazard assessment and prediction and provide support for hazard prevention and urban/rural planning.Zhijie Jia Jianbing Peng Quanzhong Lu Penghui Ma Jianwei Qiao Feiyong Wang Mingdong Zang Yang Liu Junyan Zhao Fengji Zhu 2023Journal of Earth Science2023,34,6:0
8Characteristics Analysis and Forecast of Fogin Changzhi Region显示文摘By analyzing meteorological data during 2000-2009,the characteristics of fog in Changzhi region and weather situation of fog weather occurrence were summarized,and forecast equation was established.Ma Penghui Yang Yanjun Sun Liyin 2015Meteorological and Environmental Research2015,6,1:0
返回顶部 每页显示:
共1页 首页 上一页 第1页 下一页 末页 /1 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费