A large number of primary oil and gas reservoirs have been discovered in Proterozoic strata all over the globe.Proterozoic sequences are widely distributed in China, and the discovery of large Sinian-aged gas reservoi...A large number of primary oil and gas reservoirs have been discovered in Proterozoic strata all over the globe.Proterozoic sequences are widely distributed in China, and the discovery of large Sinian-aged gas reservoirs in the Sichuan Basin and Mesoproterozoic liquid oil seepages in North China shows that attention should be paid to the exploration potential of Proterozoic strata. In this paper, the main controlling factors of Proterozoic source rocks are discussed. Principally, active atmospheric circulation and astronomical cycles may have driven intense upwelling and runoff to provide nutrients; oxygenated oceanic surface waters could have provided suitable environments for the organisms to thrive; volcanic activity and terrestrial weathering caused by continental break-up would have injected large amounts of nutrients into the ocean, leading to persistent blooms of marine organisms; and extensive anoxic deep waters may have created ideal conditions for the preservation of organic matter. Additionally, the appearance of eukaryotes resulted in diversified hydrocarbon parent material, which effectively improved the generation potential for oil and gas. Through the comparison of Formations across different cratons, seven sets of Proterozoic organic-rich source rocks have been recognized in China, which mainly developed during interglacial periods and are also comparable worldwide. The Hongshuizhuang and Xiamaling Formations in North China have already been identified previously as Mesoproterozoic source rocks. The early Proterozoic Changchengian System is highly promising as a potential source rock in the Ordos Basin. In the Upper Yangtze area, the Neoproterozoic Datangpo and Doushantuo Formations are extensively distributed, and represent the major source rocks for Sinian gas reservoirs in the Sichuan Basin. Moreover, the Nanhuan System may contain abundant shales with high organic matter contents in the Tarim Basin, although this possibility still needs to be verified. Indeed, all three cratons may contain sour展开更多
Based on the outcrop,drilling and seismic data,the sedimentary successions,evolution and hydrocarbon exploration potential of the Neoproterozoic rift basin in the northern Tarim were firstly analyzed.Due to assembly a...Based on the outcrop,drilling and seismic data,the sedimentary successions,evolution and hydrocarbon exploration potential of the Neoproterozoic rift basin in the northern Tarim were firstly analyzed.Due to assembly and breakup of the Rodinia supercontinent,the Tabei paleocontinent and the Tarim paleocontinent were developed in the Tarim craton with an EW-trending back-arc rift basin between them during Neoproterozoic time;very thick marine clastic rocks,carbonate rocks and volcanic rocks(including tillite)were deposited in the Kuruktag and Aksu area of the northern Tarim,which experienced deep sea,bathyal sea and littoral sea environments with transitional delta and ice-sea.During the Early Cryogenian and the Late Ediacaran,the northern rift basin evolved from the deep sea to the littoralneritic sea,while the lithology changed from clastic rocks to carbonate rocks.According to the field and production data,the formation and preservation of the source rocks and reservoirs indicate a good exploration potential of the Neoproterozoic rift basin.展开更多
The bonded-particle model(BPM)is commonly used in the numerical analysis of ore samples.To improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher,the parameters of the BP...The bonded-particle model(BPM)is commonly used in the numerical analysis of ore samples.To improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher,the parameters of the BPM for the ore must be calibrated.In this study,a calibration method was proposed for the scientific determination of the parameters of the BPM for ore undergoing uniaxial compression.First,physical tests and simulations were conducted to determine the mechanical response(uniaxial compressive strength and macroscopic stiffness)of ore during uniaxial compression.Then,the sensitivity of the mechanical response to the values of microscopic parameters was tested using a Plackett-Burman design.Next,the microscopic parameters with the greatest impact on the response were identified,and the range of parameters that met the target response was determined using a steepest ascent design;Second,a second-order model of the mechanical response was established using the sensitive parameters by combining a Box-Behnken design with response surface methodology to obtain the optimal BPM parameters.Simulation tests showed that the normal stiffness per unit area,critical shear stress,and bonded disk radius had significant effects on the uniaxial compressive strength(UCS)and macroscopic stiffness(MS).To verify the validity of the proposed calibration method,laboratory tests were conducted.The consistency of the simulation results with experimental results indicated that response surface methodology with the Plackett-Burman design,steepest ascent design,and Box-Behnken design can be an effective method for calibrating the BPM of ores.展开更多
According to the aeromagnetic,seismic,and geological data,the surface structure,sedimentation,and distribution characteristics as well as the deep dynamic mechanism of the north-south differentiated Neoproterozoic rif...According to the aeromagnetic,seismic,and geological data,the surface structure,sedimentation,and distribution characteristics as well as the deep dynamic mechanism of the north-south differentiated Neoproterozoic rift basins were well investigated to reveal the tectonic evolution and its control on the distribution of the Early Cambrian sedimentary basin and source rocks in the Tarim Basin.The rift basin in the southern Tarim was a product of superplume activities during the early breakup period of the Rodinia supercontinent.It initiated in the Early Cryogenian(about 780 Ma)and appeared as NE-direction aulacogens extending into the Tarim Basin.The rift basin in the northern Tarim was a back-arc rift basin derived from the subduction of Pan-Rodinian oceanic plate,which initiated in the Late Cryogenian(about 740 Ma)and occurred as a nearly EW-direction narrow band across the Tarim Basin.The northern Tarim back-arc rift basin had similar formation and evolution process to the Late Mesozoic-Cenozoic back-arc rift basins in East Asia,both showing an oceanward migration;however,the Tarim rift basin finally evolved from the fault-depression basins into passive continental margin.The Neoproterozoic rift basins controlled not only the distribution of source rocks in the syn-rift period but also the development of Early Cambrian sedimentary basin.Nearly EW-distributed syn-rift(Cryogenian to Ediacaran)and postrift(Lower Cambrian Yurtusi period)source rocks were likely to develop between the present Tabei uplift and central uplift belt.展开更多
Acidosis,regardless of hypoxia involvement,is recognized as a chronic and harsh tumor microenvironment(TME)that educates malignant cells to thrive and metastasize.Although overwhelming evidence supports an acidic envi...Acidosis,regardless of hypoxia involvement,is recognized as a chronic and harsh tumor microenvironment(TME)that educates malignant cells to thrive and metastasize.Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression,the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy.Here,chemical-induced and transgenic mouse models for colon,liver and lung cancer were established,respectively.miR-7 and TGF-β2 expressions were examined in clinical tissues(n=184).RNA-seq,miRNA-seq,proteomics,biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis.Our data show that lung cancer is sensitive to the increased acidification of TME,and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5 p.TGF-β2 is a direct target of miR-7-5 p.The reduced expression of miR-7-5 p subsequently increases the expression of TGF-β2 which enhances the metastatic potential of the lung cancer.Indeed,overexpression of miR-7-5 p reduces the acidic p H-enhanced lung cancer metastasis.Furthermore,the human lung tumor samples also show a reduced miR-7-5 p expression but an elevated level of activated TGF-β2;the expressions of both miR-7-5 p and TGF-β2 are correlated with patients’survival.We are the first to identify the role of the miR-7/TGF-β2 axis in acidic p H-enhanced lung cancer metastasis.Our study not only delineates how acidification directly affects tumorigenesis,but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer(NSCLC)treatment.Our study opens an avenue to explore the p H-sensitive subcellular components as novel therapeutic targets for cancer treatment.展开更多
As an efficient and advanced line inspection method, helicopter line patrol is gradually more and more used in transmission lines inspection, promoting the elaborate operation of transmission lines and reducing the ma...As an efficient and advanced line inspection method, helicopter line patrol is gradually more and more used in transmission lines inspection, promoting the elaborate operation of transmission lines and reducing the management cost. However, as a 'floating-potential conductor' near to a high-voltage transmission line, the helicopter would be at a high electric field region;and bring security risk to equipment and operating personnel. In this paper, the electric field strength near the cabin at locations of different distance from transmission lines is investigated by calculation, and the field in the helicopter cabin is also calculated with finite element method (FEM). The result indicates that the potential difference becomes higher with the decrease of the distance between the helicopter and transmission line. Considering the discharge energy and the guarantee of the persons’ safety, the safety distance is determined as d≥15 m.展开更多
基金supported by the National Key Research and Development Program of China (Grant No. 2017YFC0603101)National Science and Technology Major Project of the Ministry of Science and Technology of China (Grant No. 2016ZX05004001)+2 种基金National Natural Science Foundation of China (Grant Nos. 41530317, 41602144)Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA14010101)Scientific Research and Technological Development Project of CNPC(Grant No. 2016A-0200)
文摘A large number of primary oil and gas reservoirs have been discovered in Proterozoic strata all over the globe.Proterozoic sequences are widely distributed in China, and the discovery of large Sinian-aged gas reservoirs in the Sichuan Basin and Mesoproterozoic liquid oil seepages in North China shows that attention should be paid to the exploration potential of Proterozoic strata. In this paper, the main controlling factors of Proterozoic source rocks are discussed. Principally, active atmospheric circulation and astronomical cycles may have driven intense upwelling and runoff to provide nutrients; oxygenated oceanic surface waters could have provided suitable environments for the organisms to thrive; volcanic activity and terrestrial weathering caused by continental break-up would have injected large amounts of nutrients into the ocean, leading to persistent blooms of marine organisms; and extensive anoxic deep waters may have created ideal conditions for the preservation of organic matter. Additionally, the appearance of eukaryotes resulted in diversified hydrocarbon parent material, which effectively improved the generation potential for oil and gas. Through the comparison of Formations across different cratons, seven sets of Proterozoic organic-rich source rocks have been recognized in China, which mainly developed during interglacial periods and are also comparable worldwide. The Hongshuizhuang and Xiamaling Formations in North China have already been identified previously as Mesoproterozoic source rocks. The early Proterozoic Changchengian System is highly promising as a potential source rock in the Ordos Basin. In the Upper Yangtze area, the Neoproterozoic Datangpo and Doushantuo Formations are extensively distributed, and represent the major source rocks for Sinian gas reservoirs in the Sichuan Basin. Moreover, the Nanhuan System may contain abundant shales with high organic matter contents in the Tarim Basin, although this possibility still needs to be verified. Indeed, all three cratons may contain sour
基金supported by the project of PetroChina(2014A-02).
文摘Based on the outcrop,drilling and seismic data,the sedimentary successions,evolution and hydrocarbon exploration potential of the Neoproterozoic rift basin in the northern Tarim were firstly analyzed.Due to assembly and breakup of the Rodinia supercontinent,the Tabei paleocontinent and the Tarim paleocontinent were developed in the Tarim craton with an EW-trending back-arc rift basin between them during Neoproterozoic time;very thick marine clastic rocks,carbonate rocks and volcanic rocks(including tillite)were deposited in the Kuruktag and Aksu area of the northern Tarim,which experienced deep sea,bathyal sea and littoral sea environments with transitional delta and ice-sea.During the Early Cryogenian and the Late Ediacaran,the northern rift basin evolved from the deep sea to the littoralneritic sea,while the lithology changed from clastic rocks to carbonate rocks.According to the field and production data,the formation and preservation of the source rocks and reservoirs indicate a good exploration potential of the Neoproterozoic rift basin.
文摘The bonded-particle model(BPM)is commonly used in the numerical analysis of ore samples.To improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher,the parameters of the BPM for the ore must be calibrated.In this study,a calibration method was proposed for the scientific determination of the parameters of the BPM for ore undergoing uniaxial compression.First,physical tests and simulations were conducted to determine the mechanical response(uniaxial compressive strength and macroscopic stiffness)of ore during uniaxial compression.Then,the sensitivity of the mechanical response to the values of microscopic parameters was tested using a Plackett-Burman design.Next,the microscopic parameters with the greatest impact on the response were identified,and the range of parameters that met the target response was determined using a steepest ascent design;Second,a second-order model of the mechanical response was established using the sensitive parameters by combining a Box-Behnken design with response surface methodology to obtain the optimal BPM parameters.Simulation tests showed that the normal stiffness per unit area,critical shear stress,and bonded disk radius had significant effects on the uniaxial compressive strength(UCS)and macroscopic stiffness(MS).To verify the validity of the proposed calibration method,laboratory tests were conducted.The consistency of the simulation results with experimental results indicated that response surface methodology with the Plackett-Burman design,steepest ascent design,and Box-Behnken design can be an effective method for calibrating the BPM of ores.
基金The work was supported by the PetroChina project(2014A-02)China Postdoctoral Science Foundation(2015M581129).
文摘According to the aeromagnetic,seismic,and geological data,the surface structure,sedimentation,and distribution characteristics as well as the deep dynamic mechanism of the north-south differentiated Neoproterozoic rift basins were well investigated to reveal the tectonic evolution and its control on the distribution of the Early Cambrian sedimentary basin and source rocks in the Tarim Basin.The rift basin in the southern Tarim was a product of superplume activities during the early breakup period of the Rodinia supercontinent.It initiated in the Early Cryogenian(about 780 Ma)and appeared as NE-direction aulacogens extending into the Tarim Basin.The rift basin in the northern Tarim was a back-arc rift basin derived from the subduction of Pan-Rodinian oceanic plate,which initiated in the Late Cryogenian(about 740 Ma)and occurred as a nearly EW-direction narrow band across the Tarim Basin.The northern Tarim back-arc rift basin had similar formation and evolution process to the Late Mesozoic-Cenozoic back-arc rift basins in East Asia,both showing an oceanward migration;however,the Tarim rift basin finally evolved from the fault-depression basins into passive continental margin.The Neoproterozoic rift basins controlled not only the distribution of source rocks in the syn-rift period but also the development of Early Cambrian sedimentary basin.Nearly EW-distributed syn-rift(Cryogenian to Ediacaran)and postrift(Lower Cambrian Yurtusi period)source rocks were likely to develop between the present Tabei uplift and central uplift belt.
基金supported by the projects of National Natural Science Foundation of China(81874367 and 82074019)Guangdong Key Laboratory for Translational Cancer research of Chinese Medicine(2018B030322011,China)+3 种基金Natural Science Foundation for Distinguished Young Scholars of Guangdong Province,China(2017A030306033)Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(2016,China)Project of Educational Commission of Guangdong Province of China(2016KTSCX012)Pearl River Nova Program of Guangzhou,China(201710010108)。
文摘Acidosis,regardless of hypoxia involvement,is recognized as a chronic and harsh tumor microenvironment(TME)that educates malignant cells to thrive and metastasize.Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression,the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy.Here,chemical-induced and transgenic mouse models for colon,liver and lung cancer were established,respectively.miR-7 and TGF-β2 expressions were examined in clinical tissues(n=184).RNA-seq,miRNA-seq,proteomics,biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis.Our data show that lung cancer is sensitive to the increased acidification of TME,and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5 p.TGF-β2 is a direct target of miR-7-5 p.The reduced expression of miR-7-5 p subsequently increases the expression of TGF-β2 which enhances the metastatic potential of the lung cancer.Indeed,overexpression of miR-7-5 p reduces the acidic p H-enhanced lung cancer metastasis.Furthermore,the human lung tumor samples also show a reduced miR-7-5 p expression but an elevated level of activated TGF-β2;the expressions of both miR-7-5 p and TGF-β2 are correlated with patients’survival.We are the first to identify the role of the miR-7/TGF-β2 axis in acidic p H-enhanced lung cancer metastasis.Our study not only delineates how acidification directly affects tumorigenesis,but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer(NSCLC)treatment.Our study opens an avenue to explore the p H-sensitive subcellular components as novel therapeutic targets for cancer treatment.
文摘As an efficient and advanced line inspection method, helicopter line patrol is gradually more and more used in transmission lines inspection, promoting the elaborate operation of transmission lines and reducing the management cost. However, as a 'floating-potential conductor' near to a high-voltage transmission line, the helicopter would be at a high electric field region;and bring security risk to equipment and operating personnel. In this paper, the electric field strength near the cabin at locations of different distance from transmission lines is investigated by calculation, and the field in the helicopter cabin is also calculated with finite element method (FEM). The result indicates that the potential difference becomes higher with the decrease of the distance between the helicopter and transmission line. Considering the discharge energy and the guarantee of the persons’ safety, the safety distance is determined as d≥15 m.
