The regional lithospheric chemical heterogeneity in-ers that the East Qinling and its adjacent cratonic re-ions , as suggested by some authors , belong to two eotectonic units,the North China subdomain including he No...The regional lithospheric chemical heterogeneity in-ers that the East Qinling and its adjacent cratonic re-ions , as suggested by some authors , belong to two eotectonic units,the North China subdomain including he North China Craton and its southern continental largin (the North Qinling Belt), and the Yangtzean ubdomain comprising the Yangtze Craton and its torthern continental margin (the South Qinh'ng Belt). In the North Qinling Belt the metamorphosed olcanic rocks and graywackes of the Early Paleozoic Oanfeng Group south of the Early Proterozoic Qinling Froup show geochemical characteristics resembling hose of the arc volcanics and arc graywackes -espectively. The Early Paleozoic granites intruding in he Qinling Group also show similar geochemical features and similar compositional polarities to the arc-type granites . The Erlangping Group north of the Qinling Group is a volcanic-sedimentary sequence produced in an Early Paleozoic back - arc basin based on geochemical evidence . It is therefore believed that the North Qinling Belt comprised the active continental margin of the North China Craton , beneath which the ancient Qinling oceanic plate underthrusted and was consumed from 480 to 380Ma ago . The South Qinling Belt is generally considered to be a passive continental margin of the Yangtze Craton on which developed the thick Sinian and Paleozoic sediments of continental shelf and continental slope fades . The source of fine -grained clastic sedimentary rocks of various geological periods has been geochemically studied.The result demonstrates that the terrigenous elastics of the South Qinling Belt came only from the Yangtze Craton prior to the Silurian , and since then began to be fed by both the Yangtze Craton and the North Qinling . The Devonian sediments display a clear two - component mixing model in their source material . The change in the source materi-al strongly suggests that the Yangtze passive continental margin approached the active continental margin of the North China Craton and finally came into contact with it during the Silurian and the Early Devonian . On both sides of the Shangdan Fault Zone , the lithospheric megasuture of the Qinh'ng orogen , are distributed the Late Paleozoic (323-262 Ma ) granites which intruded in the Danfeng Group and the Qinling Group to the north , and in the Devonian strata to the south of the suture . The older granites of that time interval are comparable in geological and geochemical characteristics to the syn - collision granites from other continent-continent collision zones . The younger calc - alkaline granites which were em placed at about 260 Ma ago have been classified as the late - collision granites by various geochemical discrimination methods . On these grounds it may be deduced that the continent - continent collision orogeny did not begin to act until the late Early Carboniferous epoch and that its main episode was the Late Paleozoic , although it might have continued to the Early Mesozoic .The collision orogeny was separated from the subduction orogeny by an interval of about 60 Ma and the subduction of the oceanic crust was accompanied by the northward shifting of the Yangtze Craton and its passive continental margin . However , the ocean basin still remained in the South Qinling Belt for a long time after the disappearance of the ocean .展开更多
Aiming at the safety distance between coal mining working face and natural gas wells in the cross-mining area of multiple mineral resources, the cross- mining area of gas and coal resources in the Ordos Basin is taken...Aiming at the safety distance between coal mining working face and natural gas wells in the cross-mining area of multiple mineral resources, the cross- mining area of gas and coal resources in the Ordos Basin is taken as the engineering background. An anti-collision early warning technology method based on vibration wave propagation attenuation monitoring is proposed to prevent collision accidents between road headers and natural gas wells. Through the steel pipe and steel pipe concrete knocking vibration test and underground digging vibration test, the research results show that: The exponential decay coefficients of the vibration wave in steel pipe, steel pipe concrete and coal rock respectively are 0.1, 0.1140 and 0.03, which are all in accordance with the exponential decay law, and the vibration wave firstly decays sharply and then decays slowly;the formula for the distance from the road header to the natural gas well was derived based on the vibration attenuation formula, to provide a new method for realizing the problem of precise and coordinated extraction by surface monitoring of the distance from down hole road headers to gas wells, collision prevention prediction and warning and prevention of collision of extraction equipment with gas wells.展开更多
目的探讨不同类型胆囊隆起性病变的 B 超特点及良恶性胆囊肿瘤 p53基因表达特点。方法全部126例分为三组:A 组胆固醇息肉组(80例),B 组胆囊腺瘤组(32例),C 组胆囊癌组(14例)。比较三组的 B 超特点。并应用免疫组化方法对 B 组及 C 组标...目的探讨不同类型胆囊隆起性病变的 B 超特点及良恶性胆囊肿瘤 p53基因表达特点。方法全部126例分为三组:A 组胆固醇息肉组(80例),B 组胆囊腺瘤组(32例),C 组胆囊癌组(14例)。比较三组的 B 超特点。并应用免疫组化方法对 B 组及 C 组标本进行 p53基因测定。结果B超对胆囊隆起性病变的检出率达96.03%,通过病变大小、数目、发生部位、基底宽度及回声强度可以帮助鉴别病变性质。B 组6例 P53(+)中4例伴中~重度非典型增生,C 组 p53(+)率较 B 组明显高(P<0.01)。结论 B 超可以帮助检出胆囊癌前期病变及胆囊癌。B、C 两组 p53基因测定结果提示胆囊癌存在腺瘤一非典型增生一癌变这一途径。展开更多
文摘The regional lithospheric chemical heterogeneity in-ers that the East Qinling and its adjacent cratonic re-ions , as suggested by some authors , belong to two eotectonic units,the North China subdomain including he North China Craton and its southern continental largin (the North Qinling Belt), and the Yangtzean ubdomain comprising the Yangtze Craton and its torthern continental margin (the South Qinh'ng Belt). In the North Qinling Belt the metamorphosed olcanic rocks and graywackes of the Early Paleozoic Oanfeng Group south of the Early Proterozoic Qinling Froup show geochemical characteristics resembling hose of the arc volcanics and arc graywackes -espectively. The Early Paleozoic granites intruding in he Qinling Group also show similar geochemical features and similar compositional polarities to the arc-type granites . The Erlangping Group north of the Qinling Group is a volcanic-sedimentary sequence produced in an Early Paleozoic back - arc basin based on geochemical evidence . It is therefore believed that the North Qinling Belt comprised the active continental margin of the North China Craton , beneath which the ancient Qinling oceanic plate underthrusted and was consumed from 480 to 380Ma ago . The South Qinling Belt is generally considered to be a passive continental margin of the Yangtze Craton on which developed the thick Sinian and Paleozoic sediments of continental shelf and continental slope fades . The source of fine -grained clastic sedimentary rocks of various geological periods has been geochemically studied.The result demonstrates that the terrigenous elastics of the South Qinling Belt came only from the Yangtze Craton prior to the Silurian , and since then began to be fed by both the Yangtze Craton and the North Qinling . The Devonian sediments display a clear two - component mixing model in their source material . The change in the source materi-al strongly suggests that the Yangtze passive continental margin approached the active continental margin of the North China Craton and finally came into contact with it during the Silurian and the Early Devonian . On both sides of the Shangdan Fault Zone , the lithospheric megasuture of the Qinh'ng orogen , are distributed the Late Paleozoic (323-262 Ma ) granites which intruded in the Danfeng Group and the Qinling Group to the north , and in the Devonian strata to the south of the suture . The older granites of that time interval are comparable in geological and geochemical characteristics to the syn - collision granites from other continent-continent collision zones . The younger calc - alkaline granites which were em placed at about 260 Ma ago have been classified as the late - collision granites by various geochemical discrimination methods . On these grounds it may be deduced that the continent - continent collision orogeny did not begin to act until the late Early Carboniferous epoch and that its main episode was the Late Paleozoic , although it might have continued to the Early Mesozoic .The collision orogeny was separated from the subduction orogeny by an interval of about 60 Ma and the subduction of the oceanic crust was accompanied by the northward shifting of the Yangtze Craton and its passive continental margin . However , the ocean basin still remained in the South Qinling Belt for a long time after the disappearance of the ocean .
文摘Aiming at the safety distance between coal mining working face and natural gas wells in the cross-mining area of multiple mineral resources, the cross- mining area of gas and coal resources in the Ordos Basin is taken as the engineering background. An anti-collision early warning technology method based on vibration wave propagation attenuation monitoring is proposed to prevent collision accidents between road headers and natural gas wells. Through the steel pipe and steel pipe concrete knocking vibration test and underground digging vibration test, the research results show that: The exponential decay coefficients of the vibration wave in steel pipe, steel pipe concrete and coal rock respectively are 0.1, 0.1140 and 0.03, which are all in accordance with the exponential decay law, and the vibration wave firstly decays sharply and then decays slowly;the formula for the distance from the road header to the natural gas well was derived based on the vibration attenuation formula, to provide a new method for realizing the problem of precise and coordinated extraction by surface monitoring of the distance from down hole road headers to gas wells, collision prevention prediction and warning and prevention of collision of extraction equipment with gas wells.
文摘目的探讨不同类型胆囊隆起性病变的 B 超特点及良恶性胆囊肿瘤 p53基因表达特点。方法全部126例分为三组:A 组胆固醇息肉组(80例),B 组胆囊腺瘤组(32例),C 组胆囊癌组(14例)。比较三组的 B 超特点。并应用免疫组化方法对 B 组及 C 组标本进行 p53基因测定。结果B超对胆囊隆起性病变的检出率达96.03%,通过病变大小、数目、发生部位、基底宽度及回声强度可以帮助鉴别病变性质。B 组6例 P53(+)中4例伴中~重度非典型增生,C 组 p53(+)率较 B 组明显高(P<0.01)。结论 B 超可以帮助检出胆囊癌前期病变及胆囊癌。B、C 两组 p53基因测定结果提示胆囊癌存在腺瘤一非典型增生一癌变这一途径。