Upper Ordovician-Lower Silurian Wufeng-Longmaxi Formation is the most developed strata of shale gas in southern China.Due to the complex sedimentary environment adjacent to the Kangdian Uplift,the favorable area for o...Upper Ordovician-Lower Silurian Wufeng-Longmaxi Formation is the most developed strata of shale gas in southern China.Due to the complex sedimentary environment adjacent to the Kangdian Uplift,the favorable area for organic-rich shale development is still undetermined.The authors,therefore,focus on the mechanism of accumulation of organic matter and the characterization of the sedimentary environment of the Wufeng-Longmaxi Shales to have a more complete understanding and new discovering of organic matter enrichment and favorable area in the marginal region around Sichuan Basin.Multiple methods were applied in this study,including thin section identification,scanning electron microscopy(SEM)observations and X-ray diffraction(XRD),and elemental analysis on outcrop samples.Five lithofacies have been defined according to the mineralogical and petrological analyses,including mudstone,bioclastic limestone,silty shale,dolomitic shale,and carbonaceous siliceous shale.The paleo-environments have been reconstructed and the organic enrichment mechanism has been identified as a reduced environment and high productivity.The Wufeng period is generally a suboxic environment and the early Longmaxi period is a reducing environment based on geochemical characterization.High dolomite content in the study area is accompanied by high TOC,which may potentially indicate the restricted anoxic environment formed by biological flourishing in shallower water.And for the area close to the Kangdian Uplift,the shale gas generation capability is comparatively favorable.The geochemical parameters implied that new favorable areas for shale gas exploration could be targeted,and more shale gas resources in the mountain-basin transitional zone might be identified in the future.展开更多
The main reason why the application of nuclear technology in petroleum exploration has not yet been accepted by most exploration workers is that they are not clear about the homologous distribution features of oil and...The main reason why the application of nuclear technology in petroleum exploration has not yet been accepted by most exploration workers is that they are not clear about the homologous distribution features of oil and gas fields and radioactive radiation. The authors hold that the disequilibrium of uranium, radium and radon as a natural radioactive series is the basic feature in the use of this technology in petroleum exploration. The invention Gamma-ray Spectral Measurement of the Equilibium Coefficient Kp and Its Embodiment of the senior author now can readily solve that problem and replace the impedient measure of normalization of uranium and potassium to thorium that had to be proposed before. Application of this impedient measure has some limitations. In areas where the surface is covered by beach or river sands, thorium minerals such as monazite may be concentrated by placering. This could result in local thorium highs that would yield local uranium and potassium lows after normalization to thorium, and these would constitute false anomalies.展开更多
Poor solubility often results in low efficacy of antitumor drugs.Nevertheless,limited research has been conducted on the potential decrease in drug efficacy following the self-assembly of hydrophobic pure drugs into n...Poor solubility often results in low efficacy of antitumor drugs.Nevertheless,limited research has been conducted on the potential decrease in drug efficacy following the self-assembly of hydrophobic pure drugs into nanodrugs,and solutions to this problem are even rarer.Loading water-insoluble antitumor drugs into nanocarriers offers a promising solution.However,intricate carrier preparation,limited drug loading capacity,and carrier-associated safety remain key challenges.In this study,based on the discovery that hydrophobic gambogic acid(GA) self-assembles into nanostructures with diminished antitumor efficacy in aqueous environments,we developed a carrier-free nanodrug system,designated as GA-S-S-AS nanoparticles(NPs),characterized by straightforward preparation,high drug loading,fluorescence imaging,tumor-targeting,and responsive drug release in reducing environments.Specifically,the hydrophobic GA was covalently linked to the hydrophilic aptamer through a disulfide bond and then self-assembled into the nanodrugs.About 92 % of drug was encapsulated in self-assembled NPs,demonstrating remarkable stability under physiological conditions and controlled release of GA in the high-glutathione environment characteristic of tumor sites.Furthermore,by utilizing the synergistic interaction between the enhanced permeability and retention(EPR) effect and ligand-receptor active targeting mechanisms,the nanodrugs significantly increased the accumulation of GA at tumor locations.Consequently,the nanodrugs exhibited optimal therapeutic efficacy against the tumor both in vitro and in vivo,significantly inhibiting tumor growth.Furthermore,the nanodrugs demonstrated enhanced biosafety compared to free GA,effectively reducing GA-induced hepatotoxicity.Taken together,these findings underscore the significant potential of this multifunctional carrier-free nanodrugs for the targeted delivery of GA,thereby laying a foundation for future endeavors aimed at developing novel formulations of hydrophobic antitumor drugs.展开更多
Surface engineering with polydopamine coatings has been considered a promising surface functionalisation tool.However,it is difficult to control the self-polymerisation for polydopamine formation,which usually causes ...Surface engineering with polydopamine coatings has been considered a promising surface functionalisation tool.However,it is difficult to control the self-polymerisation for polydopamine formation,which usually causes severe interparticle aggregation.In this study,polydopamine self-polymerisation was controlled by adjusting its reducing environment using a reductant(NaBH4)to fabricate mixed cellulose ester(MCE)/polydopamine membranes.An oxidising environment using NaIO4 was additionally tested as the control.The results showed that a thin polydopamine coating with small polydopamine particles was formed on the skeleton frameworks of the MCE membrane with NaBH4,and the self-polymerisation rate was suppressed.The polydopamine coating formed in the reducing environment facilitated excellent water transport performance with a water permeance of approximately 400 L·m^(−2)·h^(−1)·bar^(−1) as well as efficient organic foulant removal with a bovine serum albumin rejection of approximately 90%.In addition,the polydopamine coating with NaBH4 exhibited both excellent chemical stability and anti-microbial activity,demonstrating the contribution of the reducing environment to the performance of the MCE/polydopamine membranes.It shows significant potential for use in water purification.展开更多
基金jointly funded by the National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(PLC20210104)China Geological Survey(DD20221661)China National Science and Technology Major Project“Test and Application of Shale Gas Exploration and Evaluation Technology(2016ZX05034004)”。
文摘Upper Ordovician-Lower Silurian Wufeng-Longmaxi Formation is the most developed strata of shale gas in southern China.Due to the complex sedimentary environment adjacent to the Kangdian Uplift,the favorable area for organic-rich shale development is still undetermined.The authors,therefore,focus on the mechanism of accumulation of organic matter and the characterization of the sedimentary environment of the Wufeng-Longmaxi Shales to have a more complete understanding and new discovering of organic matter enrichment and favorable area in the marginal region around Sichuan Basin.Multiple methods were applied in this study,including thin section identification,scanning electron microscopy(SEM)observations and X-ray diffraction(XRD),and elemental analysis on outcrop samples.Five lithofacies have been defined according to the mineralogical and petrological analyses,including mudstone,bioclastic limestone,silty shale,dolomitic shale,and carbonaceous siliceous shale.The paleo-environments have been reconstructed and the organic enrichment mechanism has been identified as a reduced environment and high productivity.The Wufeng period is generally a suboxic environment and the early Longmaxi period is a reducing environment based on geochemical characterization.High dolomite content in the study area is accompanied by high TOC,which may potentially indicate the restricted anoxic environment formed by biological flourishing in shallower water.And for the area close to the Kangdian Uplift,the shale gas generation capability is comparatively favorable.The geochemical parameters implied that new favorable areas for shale gas exploration could be targeted,and more shale gas resources in the mountain-basin transitional zone might be identified in the future.
文摘The main reason why the application of nuclear technology in petroleum exploration has not yet been accepted by most exploration workers is that they are not clear about the homologous distribution features of oil and gas fields and radioactive radiation. The authors hold that the disequilibrium of uranium, radium and radon as a natural radioactive series is the basic feature in the use of this technology in petroleum exploration. The invention Gamma-ray Spectral Measurement of the Equilibium Coefficient Kp and Its Embodiment of the senior author now can readily solve that problem and replace the impedient measure of normalization of uranium and potassium to thorium that had to be proposed before. Application of this impedient measure has some limitations. In areas where the surface is covered by beach or river sands, thorium minerals such as monazite may be concentrated by placering. This could result in local thorium highs that would yield local uranium and potassium lows after normalization to thorium, and these would constitute false anomalies.
基金the National Natural Science Foundation of China (Nos.21907076 and 31901908)the Natural Science Foundation of Tianjin (No.22JCQNJC01570)。
文摘Poor solubility often results in low efficacy of antitumor drugs.Nevertheless,limited research has been conducted on the potential decrease in drug efficacy following the self-assembly of hydrophobic pure drugs into nanodrugs,and solutions to this problem are even rarer.Loading water-insoluble antitumor drugs into nanocarriers offers a promising solution.However,intricate carrier preparation,limited drug loading capacity,and carrier-associated safety remain key challenges.In this study,based on the discovery that hydrophobic gambogic acid(GA) self-assembles into nanostructures with diminished antitumor efficacy in aqueous environments,we developed a carrier-free nanodrug system,designated as GA-S-S-AS nanoparticles(NPs),characterized by straightforward preparation,high drug loading,fluorescence imaging,tumor-targeting,and responsive drug release in reducing environments.Specifically,the hydrophobic GA was covalently linked to the hydrophilic aptamer through a disulfide bond and then self-assembled into the nanodrugs.About 92 % of drug was encapsulated in self-assembled NPs,demonstrating remarkable stability under physiological conditions and controlled release of GA in the high-glutathione environment characteristic of tumor sites.Furthermore,by utilizing the synergistic interaction between the enhanced permeability and retention(EPR) effect and ligand-receptor active targeting mechanisms,the nanodrugs significantly increased the accumulation of GA at tumor locations.Consequently,the nanodrugs exhibited optimal therapeutic efficacy against the tumor both in vitro and in vivo,significantly inhibiting tumor growth.Furthermore,the nanodrugs demonstrated enhanced biosafety compared to free GA,effectively reducing GA-induced hepatotoxicity.Taken together,these findings underscore the significant potential of this multifunctional carrier-free nanodrugs for the targeted delivery of GA,thereby laying a foundation for future endeavors aimed at developing novel formulations of hydrophobic antitumor drugs.
基金This work was supported by the National Natural Science Foundation of China(Grant No.21878279)Fundamental Research funds for the Central Universities(No.201841012)Natural science fund of Shandong Province Project(No.ZR2018MB032)。
文摘Surface engineering with polydopamine coatings has been considered a promising surface functionalisation tool.However,it is difficult to control the self-polymerisation for polydopamine formation,which usually causes severe interparticle aggregation.In this study,polydopamine self-polymerisation was controlled by adjusting its reducing environment using a reductant(NaBH4)to fabricate mixed cellulose ester(MCE)/polydopamine membranes.An oxidising environment using NaIO4 was additionally tested as the control.The results showed that a thin polydopamine coating with small polydopamine particles was formed on the skeleton frameworks of the MCE membrane with NaBH4,and the self-polymerisation rate was suppressed.The polydopamine coating formed in the reducing environment facilitated excellent water transport performance with a water permeance of approximately 400 L·m^(−2)·h^(−1)·bar^(−1) as well as efficient organic foulant removal with a bovine serum albumin rejection of approximately 90%.In addition,the polydopamine coating with NaBH4 exhibited both excellent chemical stability and anti-microbial activity,demonstrating the contribution of the reducing environment to the performance of the MCE/polydopamine membranes.It shows significant potential for use in water purification.
