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精整机组中剖带钢单卷取工艺及其控制方法 被引量:2
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作者 孙亚波 张康武 +2 位作者 任玉成 刘军 陈声鹤 《重型机械》 2021年第2期62-66,共5页
本文分析了精整机组中剖带钢生产的双卷取机双卷取方式存在的设备投资多、占地面积大、能耗高的问题。研究了剖分后两条并行带钢运行机理,分析计算了分离辊的分离能力,提出了中剖带钢单卷取工艺流程及其控制方法。通过带钢间隙检测系统... 本文分析了精整机组中剖带钢生产的双卷取机双卷取方式存在的设备投资多、占地面积大、能耗高的问题。研究了剖分后两条并行带钢运行机理,分析计算了分离辊的分离能力,提出了中剖带钢单卷取工艺流程及其控制方法。通过带钢间隙检测系统实时控制带钢间隙值恒定,保证卷取到卷取机上两个钢卷卷形合格,实现了带钢中剖生产机组运行稳定,产品质量合格,也有效解决了精整机组中剖带钢双卷取机双卷取生产方式存在的问题。 展开更多
关键词 精整 中剖 分离辊 单卷取 控制方法
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2500吨级半舱甲板货船中剖面设计
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作者 陈荣堤 《船舶设计技术交流》 2005年第2期25-26,共2页
本文通过对2500吨级半舱甲板货船四种中剖面结构形式的总纵强度进行计算比较分析,得出较优的中剖面形式是:采用下甲板与内舷板相连接在下甲板平面,内舷板下设甲板纵桁及支柱,其中剖面截面积较其他形式减少2.7%-3.6%,重量可降... 本文通过对2500吨级半舱甲板货船四种中剖面结构形式的总纵强度进行计算比较分析,得出较优的中剖面形式是:采用下甲板与内舷板相连接在下甲板平面,内舷板下设甲板纵桁及支柱,其中剖面截面积较其他形式减少2.7%-3.6%,重量可降低,是值得进一步研究的半舱甲板货船船型结构方式,可供设计参考。 展开更多
关键词 半舱甲板货船 中剖 设计
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电针中髎、会阳穴治疗良性前列腺增生症30例 被引量:5
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作者 张兴桥 杨涛 +1 位作者 王绣锦 李兆辉 《河北中医》 2008年第8期850-852,共3页
目的观察电针中髎、会阳穴治疗良性前列腺增生症(BPH)的临床疗效。方法将60例BPH患者随机分为2组。治疗组30例电针双侧中髎、会阳穴,留针30min,隔日针刺1次,每周治疗3次,6次为1个疗程。对照组30例予盐酸特拉唑嗪片2mg,每日1次睡前服。治... 目的观察电针中髎、会阳穴治疗良性前列腺增生症(BPH)的临床疗效。方法将60例BPH患者随机分为2组。治疗组30例电针双侧中髎、会阳穴,留针30min,隔日针刺1次,每周治疗3次,6次为1个疗程。对照组30例予盐酸特拉唑嗪片2mg,每日1次睡前服。治疗4周后观察2组治疗前后国际前列腺症状评分(I-PSS)、泌尿症状困扰积分(BS)、最大尿流率(Qmax)、膀胱残余尿(PVR)、24h憋尿困难次数和前列腺体积的变化情况及2组的临床疗效。结果治疗组总有效率86.7%,对照组总有效率89.7%,2组比较差异无统计学意义(P>0.05);2组治疗前后I-PSS、夜尿次数、BS、Qmax、PVR、24h憋尿困难次数及前列腺体积比较差异均有统计学意义(P<0.01);2组治疗前后PVR差值比较差异有统计学意义(P<0.01),治疗组改善PVR的疗效优于对照组(P<0.01)。结论电针中髎、会阳穴治疗BPH疗效确切,可显著改善BPH患者症状,增加Qmax,减少膀胱残余尿。 展开更多
关键词 电针 前列腺增生 中剖 会阳
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Basal birds from China:a brief review 被引量:4
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作者 李东升 Corwin SULLIVAN +1 位作者 周忠和 张福成 《Chinese Birds》 2010年第2期83-96,共14页
We use the term 'basal birds' for a relatively small number of primitive fossil birds that fall outside the major clade Ornithothoraces,which includes both modern birds and enantiorni-thines. Eight genera and ... We use the term 'basal birds' for a relatively small number of primitive fossil birds that fall outside the major clade Ornithothoraces,which includes both modern birds and enantiorni-thines. Eight genera and twelve valid species have been reported from China in the last 15 years,whereas Archaeopteryx lithographica remains the only basal bird to have been described from non-Chinese specimens(although confuciusornithid material is apparently present in North Korea).Here we briefly review the Chinese basal birds and their anatomy,phylogeny and ecology.Chinese fossils have contributed extensively to scientific understanding of early avian evolution,demon-strating collectively that basal birds were generally relatively large and morphologically and eco-logically quite diverse.Although some significant uncertainties remain,particularly with respect to the relative phylogenetic positions of Jeholornis,Sapeornis and Zhongornis,an increasingly clear picture of the first stages of avian evolution is emerging from the Chinese fossil record. 展开更多
关键词 basal birds China ANATOMY PHYLOGENY ECOLOGY
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Racial differences in the anatomical distribution of colorectal cancer:a study of differences between American and Chinese patients 被引量:30
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作者 San-HuaQing Kai-YunRao +1 位作者 Hui-YongJiang StevenD.Wexner 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第4期721-725,共5页
AIM: To compare the racial differences of anatomical distribution of colorectal cancer (CRC) and determine the association of age, gender and time with anatomical distribution between patients from America (white) and... AIM: To compare the racial differences of anatomical distribution of colorectal cancer (CRC) and determine the association of age, gender and time with anatomical distribution between patients from America (white) and China (oriental).METHODS: Data was collected from 690 consecutive patients in Cleveland Clinic Florida, U.S.A. and 870consecutive patients in Nan Fang Hospital affiliated to the First Military Medical University, China over the past 11years from 1990 to 2000. All patients had colorectal adenocarcinoma diagnosed by histology and underwent surgery.RESULTS: The anatomical subsite distribution of tumor,age and gender were significantly different between white and oriental patients. Lesions in the proximal colon (P<0.001) were found in 36.3 % of white vs 26.0 % of oriental patients and cancers located in the distal colon and rectum in 63.7 % of white and 74 % of oriental patients (P<0.001). There was a trend towards the redistribution from distal colon and rectum to proximal colon in white males over time, especially in older patients (>80 years).No significant change of anatomical distribution occurred in white women and Oriental patients. The mean age at diagnosis was 69.0 years in white patients and 48.3 years in Oriental patients (P<0.001).CONCLUSION: This is the first study comparing the anatomical distribution of colorectal cancers in whites and Chinese patients. White Americans have a higher risk of proximal CRC and this risk increased with time. The proportion of white males with CRC also increased with time.Chinese patients were more likely to have distal CRC and developed the disease at a significantly earlier age than white patients. These findings have enhanced our understanding of the disease process of colorectal cancer in these two races. 展开更多
关键词 Asian Continental Ancestry Group European Continental Ancestry Group ADENOCARCINOMA ADULT Age Distribution Aged Aged 80 and over China Colonic Neoplasms Colorectal Neoplasms Comparative Study Female Humans Male Middle Aged Rectal Neoplasms Retrospective Studies United States
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Nitrate Accumulation in Soil Profile of Dry Land Farming in Northwest China 被引量:25
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作者 FAN Jun, HAO Ming-De and SHAO Ming-AnState Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, the Chinese Academy of Sciences, Yangling 712100 (China). 《Pedosphere》 SCIE CAS CSCD 2003年第4期367-374,共8页
A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coars... A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coarse-textured dark loessial soilafter continuous winter wheatcropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or incombination. Annual N and P (P_2O_5) rates were 0, 45, 90, 135 and 180 kg ha^(-1). After 15successive cropping cycles, the soil samples were taken from each treatment for analysis of NO_3-Nconcentration. The results showed that NO_3-N distribution in the soil profile was quite differentamong the treatments. The application of fertilizer N alone resulted in higher NO_3-N concentrationin the soil profile than the combined application of N and P, showing that application of P couldgreatly reduce the NO_3-N accumulation. With an annual application of 180 kg N ha^(-1) alone, a peakin NO_3-N accumulation occurred at 140 cm soildepth, and the maximum NO_3-N concentration in thesoils was 67.92 mg kg^(-1). The amount of NO_3-N accumulated in the soil profile decreased as thecumulative N uptake by the winter wheat increased. Application of a large amount of N resulted inlowerN recoveries in winter wheat and greater NO_3-N accumulation in soil profile. KO_3-N did notenter underground water in the study region; therefore, there is no danger of underground waterpollution. Amount of NO_3-N accumulation can be predicted by an equation according to annual N and Prates based on the results of this experiment. 展开更多
关键词 dry land long-term fertilizer experiment NO_3-N accumulation WHEAT
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The importance of non-carbonate mineral weathering as a soil formation mechanism within a karst weathering profile in the SPECTRA Critical Zone Observatory, Guizhou Province,China 被引量:2
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作者 Oliver W.Moore Heather L.Buss +2 位作者 Sophie M.Green Man Liu Zhaoliang Song 《Acta Geochimica》 EI CAS CSCD 2017年第3期566-571,共6页
Soil degradation, including rocky desertification,of the karst regions in China is severe. Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded. Understa... Soil degradation, including rocky desertification,of the karst regions in China is severe. Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded. Understanding the balance between soil formation and soil erosion is critical for long-term soil sustainability, yet little is known about the initial soil forming processes on karst terrain. Herein we examine the initial weathering processes of several types of carbonate bedrock containing varying amounts of non-carbonate minerals in the SPECTRA Critical Zone Observatory, Guizhou Province, Southwest China. We compared the weathering mechanisms of the bedrock to the mass transfer of mineral nutrients in a soil profile developed on these rocks and found that soil formation and nutrient contents are strongly dependent upon the weathering of interbedded layers of more silicate-rich bedrock(marls). Atmospheric inputs from dust were also detected. 展开更多
关键词 Critical zone Chemical weathering KARST DESERTIFICATION Guizhou Province
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AVO Character Research of Natural Gas Hydrates in the East China Sea 被引量:1
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作者 LIU Huaishan HUANG Guangnan HE Yi TONG Siyou CUI Shuguo ZHANG Jin 《Journal of Ocean University of China》 SCIE CAS 2009年第3期270-276,共7页
Natural gas hydrates are considered as strategic resources with commercial potential in the 21st century. Obvious BSR characteristics will be shown on seismic profiles, if there exist natural gas hydrates. The AVO met... Natural gas hydrates are considered as strategic resources with commercial potential in the 21st century. Obvious BSR characteristics will be shown on seismic profiles, if there exist natural gas hydrates. The AVO method is one of the methods which can be used to identify and forecast lithologic characteristics and fluid properties by using the relationship between Amplitude and Offset. AVO anomaly is one of the significant signs to check out whether or not there is free gas below the BSR, so it can be used to detect natural gas hydrates from the seismic profile. Considering the geological and geophysical characteristics of the Okinawa Trough and making use of the techniques mentioned above, we can conclude that the conditions there are favorable for the formation and concentration of natural gas hydrates. By analyzing the data collected from the study area, one can discover many different anomalous phenomena on the seismic profile which are related to the existence of natural gas hydrates. Preliminary estimation of the natural gas hydrates in the Okinawa Trough shows that the trough is rich in natural gas hydrates and may become a potential important resources exploration area. 展开更多
关键词 natural gas hydrates free gas blank zone Okinawa Trough
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Relocation of Earthquakes in Shandong and Its Neighboring Areas,China and Its Relationship with Active Tectonics
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作者 Li Xia Liu Xiqiang +2 位作者 Li Yajun Dong Xiaona Zhang Huifeng 《Earthquake Research in China》 2013年第4期512-526,共15页
Earthquakes taking place from 1975 to 2010 in and around Shandong Province are relocated using double-difference(HypoDD)and Hypoinvers 2000(Hypo2000)methods,after correction of the onset times of seismic phases.The re... Earthquakes taking place from 1975 to 2010 in and around Shandong Province are relocated using double-difference(HypoDD)and Hypoinvers 2000(Hypo2000)methods,after correction of the onset times of seismic phases.The results show that the relocated seismicity is clearly associated with regional tectonics in space,and is also in agreement with the existence of deep faults imaged by wide-angle and deep seismic reflection profiling;most of the focal depths are in the range of 5~25km,and there are clearly two predominant depths:10km and 16km,which are inferred to be on the bottom of the upper crust and in the middle crust,respectively.The pattern of seismic activity indicates that moderate and strong earthquakes are likely to occur in the brittle-ductile transition zone between the upper and the lower crust,as the outcome of the deep tectonic dynamic process and the movement and deformation of faults in the upper and shallow crust under the regional stress field. 展开更多
关键词 The double-difference algorithm SEISMOTECTONICS Focal depth Predominantdepth of earthquakes Brittle-ductile transition
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Sulphur Status in Some Surface Horizons and Typical Profiles of Soils Derived from Xiashu Loess in China
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作者 LIANGYONG-CHAO MATONG-SHENG 《Pedosphere》 SCIE CAS CSCD 1994年第4期331-338,共8页
Studies were conducted to examine factors which might influence the status and distribution of S insome surface horizons and typical profiles of soils derived from Xiashu loess on the upper.slope (US), middleslope (MS... Studies were conducted to examine factors which might influence the status and distribution of S insome surface horizons and typical profiles of soils derived from Xiashu loess on the upper.slope (US), middleslope (MS) and lower slope (LS) of Nanjing-Zhenjiang-Yangzhou hilly zone. The total S contents varied from70.30 to 350.21 mg/kg, and the average for all surface soils was 218.3 mg/kg. The average S contents inthe profiles followed the sequence: US<MS<LS. The total S was closely correlated with organic S, inorganicS, organic matter, total N, amorphous iron oxide (Fe_o) and the ratio of amorphous iron oxide to free ironoxide (Fe_o/Fe_a), but no significant relationship was found between total S and the ratio of free iron oxideto total iron (Fe_d/Fe_t). Inorganic sulphate in paddy soils (MS and LS) was nearly higher in surface soilthan in subsurface soil and subsoil, it, however, remained relatively unchanged with increasing depth for theoriginal soil profile (US). The average organic S accounted for 94% of the total S in the surface soils, butthe percentage decreased with depth in the profiles. Like the total S, the organic and inorganic S contentswere highly significantly correlated with organic matter, total N, Fe. and Fe_o/Fe_d ratio, but they wereinsignificantly related to Fe_d/Fe_t ratio. The C/S and N/S ratios in this study were somewhat lower thanthe results reported by others. The C/N/S ratios varied considerably within the same profile and amongdifferent soils but they fell within the range of values reported worldwide. 展开更多
关键词 paddy soil sulphur distribution sulphur status
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The age measures and its layer sequence tratigraphy of Late Quaternary sediment in Lushan Dajiaochang of China
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作者 Hu Dongsheng Hu Rong +5 位作者 Li Xiaoyu Hu Wenxuan Wang Xulong Tian Xingong Liu Weiguo Zhang Guowei 《Engineering Sciences》 EI 2013年第6期48-57,共10页
Through the scientific investigation on Lushan for a long time, detailed studies have been carried out on the geologic stratum section of Late Quaternary in Dajiaochang. The series age data of complete stratigraphic s... Through the scientific investigation on Lushan for a long time, detailed studies have been carried out on the geologic stratum section of Late Quaternary in Dajiaochang. The series age data of complete stratigraphic section and full time formation since 400 kaBP were based on the results of the analyses using the dating methods with various instruments such as the ancient geomagnetism, electronics spin resonance (ESR), 36C1 and lumines- cence dating, etc. Corresponding to these data, it identified the paleomagnetic polarity events including Biwa- III event (320 kaBP), Biwa- 1I event (260 kaBP), Biwa- I event (180 kaBP, scarcity due to the disturbance of the iron dish), Blake event (100 kaBP) and Laschamp event (20 kaBP, didn't grow due to the activities of the surface), etc. Combined with the sequence stratigraphy, layer type characteristics and its sediment environment, the strati- graphic can be divided into 4 stages of development respectively : Stage [ is the climate period of glacial epoch (200-400 kaBP); stage 11 is the climate period of interglacial epoch (100-200 kaBP); stage llI is the climate peri- od of periglacial epoch (10-100 kaBP); stage IV is the climate period ofpostglacial epoch (0-10 kaBP). 展开更多
关键词 sediment of Late Quaternary various instrument dating data layer type sequence and integrated ages Dajiaochang area of Lushan
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Characteristics of heavy metals in soils under different land use in a typical karst area, Southwest China 被引量:3
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作者 Yang Tang Guilin Han 《Acta Geochimica》 EI CAS CSCD 2017年第3期515-518,共4页
This study investigated the distribution of six pollutant elements(Cr, Cu, Pb, Zn, Cd, and As), and their relationship to soil organic carbon(SOC) in five soil profiles in the Puding area. Results show SOC content dec... This study investigated the distribution of six pollutant elements(Cr, Cu, Pb, Zn, Cd, and As), and their relationship to soil organic carbon(SOC) in five soil profiles in the Puding area. Results show SOC content decreased exponentially to the depth of soil profiles; the vertical distribution patterns of SOC in soil profiles were partially controlled by land use. The concentrations of these pollutant elements in most soils were lower than background values, indicating that the local soil was less likely to be contaminated by foreign inputs. Geo-accumulation index values of these elements in most soil samples were less than 1, suggesting that the soil of this area may not be polluted. The concentrations of Cr, Cu, As, and Zn in soils from all land use types were significantly negatively correlated with SOC contents. Geochemical approaches confirmed that the soil of this area was less influenced by pollutant elements. 展开更多
关键词 Heavy metals Soil organic carbon Land use KARST Southwest China
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Impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate 被引量:1
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作者 Xiao-Nan HE Jin-Liang ZHAN +4 位作者 Cheng ZHANG Yu CHEN Wei GONG Wang JI Shao-Ping NIE 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第4期315-320,共6页
Objective To investigate the impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate. Methods A linear regression analysis was performed in monsoonal climate epidemio... Objective To investigate the impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate. Methods A linear regression analysis was performed in monsoonal climate epidemiological survey for a period of four years on the impact of meteorological factors (minimal temperature, mean temperature, maximal temperature, average daily surface temperature, day temperature range, relative humidity, mean wind speed, and atmospheric pressure) and PM2.5 concentration on the daily incidences of acute aortic dissections. Meteorological variables and PM2.5 concentration were retrieved on a daily basis from Beijing Regional Climate Center and the Ministry of Environmental Protection of the People’s Republic of China’s website, and the daily incidences of acute aortic dissections were retrieved from the Clinical Data Analysis and Reporting System in the Emergency and Critical Care Center of Beijing Anzhen Hospital. Results During the study period (from January 2011 to December 2014), 1164 patients were identified as having acute aortic dissections. The corresponding incidences in spring and autumn were 0.96 and 1.00, respectively, which significantly higher than that in summer and winter. The incidences of acute aortic dissection in a day could be predicted by diurnal temperature range (DTR) using the following linear multiple regression models: incidences of acute aortic dissection = 0.543 + 0.025 × DTR. Conclusion This is the first study to show an attributable effect of DTR on acute aortic events in monsoonal climate. Our study confirms that meteorological variables were important factors influencing the incidence of acute aortic dissection. 展开更多
关键词 Acute aortic dissection Meteorological conditions PM2.5
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A potential stratotype for the regional lowermost stage of the continental Paleocene in China 被引量:3
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作者 LI WeiTong LIU GengWu +5 位作者 Dennis R.BRAMAN LI YiBin CAO WeiSheng Don BRINKMAN SHEN Jiao CHEN QingBao 《Science China Earth Sciences》 SCIE EI CAS 2014年第5期1109-1116,共8页
Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined throug... Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined through its lower boundary stratotype,i.e.the continental Cretaceous/Paleogene boundary stratotype.There is no section yet found which contains continuous terrestrial deposits and biostratigraphic records of the Cretaceous-Paleogene transition in Nanxiong,Guangdong and Jiayin,Heilongjiang,there is no evidence for establishing the continental stratotype of the Cretaceous/Paleogene boundary in either area.Therefore,both the"Shanghuan stage"and"Furaoan stage"are not good candidates for the lowermost stage of the Paleocene of China.From the viewpoint of charophytes,the outcrop section of the Dangyang,Hubei Province(Central China)contains the most continuous,abundant and diverse terrestrial biostratigraphic records of the Cretaceous-Paleogene transition,in particular the early Paleocene,known so far in the world.The biostratigraphic records of ostracods in the transition are also continuous,rich,and diverse.The Dangyang outcrop section is the only section known so far in China that is a possible candidate for a continental stratotype of the Cretaceous/Paleogene boundary in China and the section is the only potential section identified to date for establishing the regional lowermost stage of the Paleocene,Paleogene and Cenozoic in China or stratotype section for the stage. 展开更多
关键词 Cretaceous/Paleogene boundary the lowermost stage of Paleocene STRATOTYPE CONTINENTAL CHAROPHYTES Dangyang sec-tion China
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2-D P-wave velocity structure of lithosphere in the North China tectonic zone: Constraints from the Yancheng-Baotou deep seismic profile 被引量:14
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作者 DUAN YongHong LIU BaoJin +5 位作者 ZHAO JinRen LIU BaoFeng ZHANG ChengKe PAN SuZhen LIN JiYan GUO WenBin 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第9期1577-1591,共15页
We obtained the 2-D P-wave velocity structure of the lithosphere in the eastern North China Craton, Shanxi fault subsidence zone, and Yinchuan-Hetao fault subsidence zone by ray tracking technology based on six groups... We obtained the 2-D P-wave velocity structure of the lithosphere in the eastern North China Craton, Shanxi fault subsidence zone, and Yinchuan-Hetao fault subsidence zone by ray tracking technology based on six groups of clearly identified crustal phases and one group of lithospheric interface reflection phases from seismic recording sections of 21 shots along the 1300-km-long Yancheng-Baotou deep seismic wide-angle reflection/refraction profile. The results indicate significant differ- ences between the lithospheric structure east and west of the Taihang Mountains, which is a gravity-gradient zone as well as a zone of abrupt change in lithospheric thickness and a separation zone of different rock components. East of the Taihang Mountains, the Mesozoic and Cenozoic lithospheric structure of the North China Craton has undergone strong reformation and destruction, resulting in the lithosphere thickness decreasing to 70-80 km. The North China Basin has a very thick Cenozoic sedimentary cover and the deepest point of crystalline basement is about 7.0 kin, with the crustal thickness decreasing to about 31.0 kin. The crystalline basement of the Luxi uplift zone is relatively shallow with a depth of 1.0-2.0 km and crustal thickness of 33.0-35.0 km. The Subei Basin has a thicker Cenozoic sedimentary cover and the bottom of its crystalline basement is at about 5.0-6.0 km with a crustal thickness of 31.0-32.0 km. The Tanlu fault is a deep fracture which cuts the lithosphere with a significant velocity structure difference on either side of the fault. The Tanlu fault plays an important role in the lithospheric destruction in the eastern part of the North China Craton. West of the Taihang Mountains, the crustal thickness increases sig- nificantly. The crust thickness beneath the Shanxi fault depression zone is about 46 km, and there is a low-velocity structure with a velocity of less than 6.1 km s-~ in the upper part of the middle crust. Combined with other geophysical study results, our data shows that the lithospheric destruction at the Shaanxi-Shanxi fault depression zone and the Yinchuan-Hetao rift surround- ing the Ordos block is non-uniform. The lithosphere thickness is about 80-90 km in the Datong-Baotou area, 75-137 km at the Dingxiang-Shenmu region, and about 80-120 km in the Anyang-Yichuan area. The non-uniform lithospheric destruction may be related to the ancient tectonic zone surrounding the Ordos block. This zone experienced multi-period tectonic events in the long-term process of its tectonic evolution and was repeatedly transformed and weakened. The weakening level is related to the interactions with the Ordos block. The continental collision between the Cenozoic India and Eurasia plates and N-E thrust- ing by the Qinghai Tibet Plateau block is causing further reformation and reduction of the lithosphere. 展开更多
关键词 North China tectonic zone deep seismic sounding crustal structure lithospheric thickness North China Craton destruction
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Missed posterior shoulder dislocation with malunited proximal humerus fracture 被引量:1
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作者 Sunil Kumar Rajesh Kumar Chopra Abhishek Kashyap Sumit Arora 《Chinese Journal of Traumatology》 CAS CSCD 2013年第6期375-378,共4页
Posterior dislocation of the shoulder may be missed or neglected at initial presentation especially in developing countries.We present a case of 40-year-old Indian man who had 3-month missed posterior dislocation of t... Posterior dislocation of the shoulder may be missed or neglected at initial presentation especially in developing countries.We present a case of 40-year-old Indian man who had 3-month missed posterior dislocation of the right shoulder along with malunited fracture of the anatomical neck of the humerus.Open reduction and stabilization with modified McLaughlin procedure was performed.Rotational osteotomy of proximal humerus had to be performed as supplementary procedure to keep the humeral head stable in glenoid cavity during functional range of movements.The patient had excellent result of the shoulder at 3 years follow-up. 展开更多
关键词 Shoulder dislocation HUMERUS Os-teotomy
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The P-wave velocity structure of the lithosphere of the North China Craton——Results from the Wendeng-Alxa Left Banner deep seismic sounding profile 被引量:27
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作者 WANG ShuaiJun WANG FuYun +4 位作者 ZHANG JianShi JIA ShiXu ZHANG ChengKe ZHAO JinRen LIU BaoFeng 《Science China Earth Sciences》 SCIE EI CAS 2014年第9期2053-2063,共11页
For the first time on the Chinese mainland, long-range wide-angle seismic reflection/refraction profiling technology has been applied to seismic wave phases from different depths and with different attributes within t... For the first time on the Chinese mainland, long-range wide-angle seismic reflection/refraction profiling technology has been applied to seismic wave phases from different depths and with different attributes within the various blocks of the North China Craton to characterize the structure of the crust and upper mantle lithosphere. By comparative analysis of the seismic wave phase characteristics in each block across a 1500-km-long east-west profile, we have identified conventional Pg, Pci, PmP and Pn phases in the crust, made a clear contrast between PL1 and PL2 waves belonging to two groups of lithospheric-scale phases, and produced a model of crust-mantle velocity structures and tectonic characteristics after one- and two-dimensional calcula- tions and processing. The results show that the thickness of the crust and lithosphere gradually deepens from east to west along the profile. However, at the reflection/refraction interface, seismic waves in each group show obvious localized changes in each block. Also, the depth to the crystalline basement changes greatly, from as much as 7.8 km in the North China fault basin to only about 2 km beneath the Jiaodong Peninsula and Taihang-Ltlliang area. The Moho morphology as a whole ranges from shallow in the east to deep in the west, with the deepest point in the Ordos Block at 47 km; in contrast, the North China Plain Block is uplifting. The L1 interface of the lithosphere is observed only to the west of Taihang Mountains, at a relatively slowly changing depth of about 80 km. The L2 interface varies from 75 to 160 km and shows a sharp deepening to the west of Tai- hang Mountains, forming a mutation belt. 展开更多
关键词 LITHOSPHERE velocity structure long observation distance crustal blocks North China Craton(NCC)
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Forward Simulation of Gravity for Crustal Structure of Xiachayu-Gonghe Profile in Eastern Tibetan Plateau
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作者 KE Xiaoping WANG Yong XU Houze 《Geo-Spatial Information Science》 2010年第4期300-305,共6页
The crustal structure of Xiachayu-Gonghe geophysical profile in eastern Tibetan plateau is simulated with Bouguer anomaly corrected for sediments and lithosphere. The forward simulation shows that the thickness of upp... The crustal structure of Xiachayu-Gonghe geophysical profile in eastern Tibetan plateau is simulated with Bouguer anomaly corrected for sediments and lithosphere. The forward simulation shows that the thickness of upper crust in eastem Tibetan plateau is about 20 km, and the density is 2.78 × 10^3 kg/m^3. The bottom interface of middle crust changes from 30 km to 40 km, the density of middle crust is 2.89 × 10^3 kg/m^3. The materials with low density of 2.78 × 10^3 kg/m^3 exist in middle crust, and those with high density of 3.33 × 10^3 kg/m^3 exist at the bottom of middle crust between Wenquan and Tanggemu. The density is 3.10× 10^3 kg/m^3 in lower crust. The shallowest depth of Moho interface is about 56 km, and the deepest one is about 74 km, the undulation of interface is large, the deep Moho is located in Xiachayu, Chayu, Nujiang, and Wenquan. The crustal density of eastern Tibetan plateau is larger than that of central section; the low velocity layers are located in middle crust and bottom in eastern Tibetan plateau and at the bottom of the upper crust in the central plateau. 展开更多
关键词 crustal structure Tibetan plateau GRAVITY forward simulation
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Modeling detector response function of alpha particles for neutron depth profiling
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作者 DOU HaiFeng LI RunDong +3 位作者 XU JiaYun YUAN Shu TANG FengPing YANG Xin 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第1期35-38,共4页
The energy spreading of recorded ions is influenced by straggling,geometrical acceptance angles and detector energy resolution effects in neutron depth profiling(NDP)and a symmetric Gaussian function model was customa... The energy spreading of recorded ions is influenced by straggling,geometrical acceptance angles and detector energy resolution effects in neutron depth profiling(NDP)and a symmetric Gaussian function model was customarily applied before.In addition,the spectra of mono-energetic alpha particles show a well known asymmetric shape as well when measured by silicon detectors.This article presents a physical model predicting the observed energy spectrum of a sample ion with target nuclides in prearranged depths.It is expressed as the convolution of a Gaussian function with a left-hand double-exponential function.Experiment showed that the predicted ions spectrum derived from the asymmetric model matches the observed energy spectrum.Therefore,the model can be applied to produce matrix for inversion of NDP spectrum. 展开更多
关键词 energy straggling neutron depth profiling Gaussian function double-exponential function physical model
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