Hydrazine,an essential chemical,has been used within a wide spectrum of industries,including pesticides,pharmaceuticals and even satellite-launching systems.However,the excessive consumption of hydrazine raised the ri...Hydrazine,an essential chemical,has been used within a wide spectrum of industries,including pesticides,pharmaceuticals and even satellite-launching systems.However,the excessive consumption of hydrazine raised the risk of environmental pollution accidents and occurrence of diseases because of its high toxicity and volatility.This led to the discovery of diverse fluorescent probes for the monitoring of the dangerous substance,including those based on organic small molecules and emerging nanomaterials.Herein,we are going to present a comprehensive review of recently reported hydrazine fluorescent probes,and discuss their structure design strategies and detection mechanisms.In particular,both organic small-molecule and nanomaterial fluorescent probes for hydrazine will be discussed together for the first time.展开更多
Elastic anisotropy of shales is critical to accurate constraints for rock physical models,quantitative interpretation and hydraulic fracturing.However,the causes of elastic anisotropy of shales are very complicated,an...Elastic anisotropy of shales is critical to accurate constraints for rock physical models,quantitative interpretation and hydraulic fracturing.However,the causes of elastic anisotropy of shales are very complicated,and the understanding of how multiple influence factors affect the elastic anisotropy of shales is still not clear.Hence,the orthogonal experiment,as an effective multiple factors experimental method,is adopted in this study to analyze the effect of multiple factors for shale elastic anisotropy.Three factors,clay content,organic matter(OM)content and compaction stress are selected as independent variables,the orthogonal test table L_(16)(4^(3))with four levels for each factor is adopted.According to the designed orthogonal table,sixteen artificial shales are constructed based on the cold-pressing method,and all the dry artificial shales are measured by the ultrasonic measurements.The influence of each factor on the elastic anisotropy and the sensitivity orders of three factors are obtained using the range analysis.The orders of sensitivity for selected factors follow the sequence clay content>compaction stress>OM content for velocity anisotropy parameters.The compaction mechanism of artificial shales is also discussed by the compaction factor,which are positively correlated with the velocity anisotropy parameters.The clay platelets orientation distribution function(ODF)of samples is evaluated by a theoretical model,the ODF coefficients are significantly affected by the clay content and compaction stress,and W200 are much more sensitive to these factors than W400.The results can provide a critical rock physics basis for quantitative interpretation and reservoir prediction of the low-maturity or maturity shale reservoir.展开更多
Humanβ-galactosidase(β-gal)is recognized as a crucial biomarker for evaluating senescence at the cellular and tissue levels in humans.However,tools to precisely track the endogenousβ-gal are still limited.Herein,we...Humanβ-galactosidase(β-gal)is recognized as a crucial biomarker for evaluating senescence at the cellular and tissue levels in humans.However,tools to precisely track the endogenousβ-gal are still limited.Herein,we present two novel self-calibratingβ-gal probes 7a and 7b which were constructed on a unique green/red dual-emissive fluorescence platform.The two probes inherently exhibited a stable green fluorescence signal impervious toβ-gal activity,serving as a reliable internal reference.They also displayed a progressively diminishing red fluorescence signal with the increasing ofβ-gal expression levels.The dual behavior endows them with self-calibration capacity and then renders excellently selective and sensitive for precisely monitoringβ-gal activity.Notably,compared with E.coliβ-gal,the two probes are more effectively response to A.oryzaeβ-gal homologous to humanβ-gal,indicating their unique species-selectivity.Furthermore,7a was validated for its effectiveness in determining senescenceassociatedβ-galactosidase(SA-β-gal)expression in senescent NRK-52E and HepG2 cells,underscoring its practical applicability in senescence research.展开更多
基金support from the National Natural Science Foundation of China(21977082 and 22037002)the Natural Science Basic Research Program of Shaanxi(2020JC-38).
文摘Hydrazine,an essential chemical,has been used within a wide spectrum of industries,including pesticides,pharmaceuticals and even satellite-launching systems.However,the excessive consumption of hydrazine raised the risk of environmental pollution accidents and occurrence of diseases because of its high toxicity and volatility.This led to the discovery of diverse fluorescent probes for the monitoring of the dangerous substance,including those based on organic small molecules and emerging nanomaterials.Herein,we are going to present a comprehensive review of recently reported hydrazine fluorescent probes,and discuss their structure design strategies and detection mechanisms.In particular,both organic small-molecule and nanomaterial fluorescent probes for hydrazine will be discussed together for the first time.
基金supported by the National Natural Science Fund Projects(42104107)the Fundamental Research Funds for the Central Universities(2022XJDC06).
文摘Elastic anisotropy of shales is critical to accurate constraints for rock physical models,quantitative interpretation and hydraulic fracturing.However,the causes of elastic anisotropy of shales are very complicated,and the understanding of how multiple influence factors affect the elastic anisotropy of shales is still not clear.Hence,the orthogonal experiment,as an effective multiple factors experimental method,is adopted in this study to analyze the effect of multiple factors for shale elastic anisotropy.Three factors,clay content,organic matter(OM)content and compaction stress are selected as independent variables,the orthogonal test table L_(16)(4^(3))with four levels for each factor is adopted.According to the designed orthogonal table,sixteen artificial shales are constructed based on the cold-pressing method,and all the dry artificial shales are measured by the ultrasonic measurements.The influence of each factor on the elastic anisotropy and the sensitivity orders of three factors are obtained using the range analysis.The orders of sensitivity for selected factors follow the sequence clay content>compaction stress>OM content for velocity anisotropy parameters.The compaction mechanism of artificial shales is also discussed by the compaction factor,which are positively correlated with the velocity anisotropy parameters.The clay platelets orientation distribution function(ODF)of samples is evaluated by a theoretical model,the ODF coefficients are significantly affected by the clay content and compaction stress,and W200 are much more sensitive to these factors than W400.The results can provide a critical rock physics basis for quantitative interpretation and reservoir prediction of the low-maturity or maturity shale reservoir.
基金the financial support from the National Natural Science Foundation of China(Nos.21977082,22037002and 21472148)the Natural Science Basic Research Program of Shaanxi(No.2020JC-38)。
文摘Humanβ-galactosidase(β-gal)is recognized as a crucial biomarker for evaluating senescence at the cellular and tissue levels in humans.However,tools to precisely track the endogenousβ-gal are still limited.Herein,we present two novel self-calibratingβ-gal probes 7a and 7b which were constructed on a unique green/red dual-emissive fluorescence platform.The two probes inherently exhibited a stable green fluorescence signal impervious toβ-gal activity,serving as a reliable internal reference.They also displayed a progressively diminishing red fluorescence signal with the increasing ofβ-gal expression levels.The dual behavior endows them with self-calibration capacity and then renders excellently selective and sensitive for precisely monitoringβ-gal activity.Notably,compared with E.coliβ-gal,the two probes are more effectively response to A.oryzaeβ-gal homologous to humanβ-gal,indicating their unique species-selectivity.Furthermore,7a was validated for its effectiveness in determining senescenceassociatedβ-galactosidase(SA-β-gal)expression in senescent NRK-52E and HepG2 cells,underscoring its practical applicability in senescence research.
