Recent results for synthesis of conjugated polymers, poly(arylene vinylene)s exemplified as poly(fluorene vinylene)s and poly(phenylene vinylene)s, by acyclic diene metathesis (ADMET) polymerization have been introduc...Recent results for synthesis of conjugated polymers, poly(arylene vinylene)s exemplified as poly(fluorene vinylene)s and poly(phenylene vinylene)s, by acyclic diene metathesis (ADMET) polymerization have been introduced. The methods using molybdenum and ruthenium catalysts afforded defect-free, high molecular weight polymers with all trans olefinic double bonds, and significant reduction of by-products (halogen, sulfur etc.) in addition of decrease of structurally defects have been attained. The methods also demonstrated precise synthesis of end-functionalized polymers that showed unique optical properties combined with the end groups. Catalytic one-pot syntheses of end-functionalized poly(9,9-dialkylfluorene-2,7-vinylene)s have been attained by both ruthenium (by chain-transfer) and molybdenum catalysts and the method should provide more green route for synthesis of conjugated materials with better device performance.展开更多
The carbonate-free fraction of 20 surface sediments collected from the ultraslow-spreading Southwest Indian Ridge(SWIR) was studied by grain size analysis and mineralogical analysis with X-ray powder diffraction(XRD),...The carbonate-free fraction of 20 surface sediments collected from the ultraslow-spreading Southwest Indian Ridge(SWIR) was studied by grain size analysis and mineralogical analysis with X-ray powder diffraction(XRD),stereo microscopy and scanning electron microscopy(SEM). The characteristics of the carbonate-free fraction of the sediments were obtained, and related influential factors were discussed. The results show that the mean grain size of this fraction is in 1.96Φ–8.19Φ, with poorly sorting and unimodal, bimodal or irregular bimodal distribution patterns. Four grain size end members of the fraction are derived with the End Member Model method. The finest end member EM1 shows a significant contribution of terrigenous materials of the aeolian input and sediment carried by the bottom current. End member EM2 with medium size mainly reflects sediment of a siliceous bioclast origin. EM3 and EM4 are interpreted as representing the coarser volcanic materials related to bedrock weathering or volcanic activities. Multi-provenance is the dominant factor controlling the grain size pattern of the carbonate-free fraction of the sediments in that area. In addition, sediment transport processes such as the bottom current and wind are the minor factors that influence the grain size distribution of the carbonate-free fraction sediments.展开更多
This study presents a laser-sheet imaging technique to measure the water surface of free overfalls with plunge pool. Varying the plunge pool length of a constant approach discharge created skimming, periodic oscillato...This study presents a laser-sheet imaging technique to measure the water surface of free overfalls with plunge pool. Varying the plunge pool length of a constant approach discharge created skimming, periodic oscillatory, and nappe flows. This study analyzes the resulting oscillating water surfaces and temporal variations of water stages at particular positions in the periodic oscillatory flow condition. The oscillation period and amplitude of temporal water stage variation were determined by directly measuring the time interval and water stage differences in water stage variations, respectively. The plunge pool length and air pocket characteristics seriously affected the periodic oscillatory flow. The oscillation period increased as the plunge pool length increased. On the other hand, the water stage amplitude decreased sharply when the plunge pool exceeded a specific length. The absence of an air pocket beneath the falling nappe significantly increased the oscillation period and decreased the water stage amplitude. This study investigates water surface oscillation in the plunge pool and the upstream side of the drop. However, the mean end depth of a periodic oscillatory flow with an air pocket is also applicable to discharge estimation using the end depth method.展开更多
AIM： To review the defnition and performance of the commonly used end points in trials of systemic thera-pies in metastatic castration-resistant prostate cancer patients. METHODS： A literature search was undertaken...AIM： To review the defnition and performance of the commonly used end points in trials of systemic thera-pies in metastatic castration-resistant prostate cancer patients. METHODS： A literature search was undertaken on PubMed database to identify studies meeting estab-lished criteria, with the aim of selecting randomized clinical trials and study definition and performance of their end points. The end points were grouped into three categories： overall survival （OS）, time-to-event end points, and response end points. A special analysis was performed for secondary end points of the studies which documented a beneft in OS in the experimental arm. Finally, publishes analyses for surrogacy of the in-cluded end points were also reported. RESULTS： OS, time-to-event and response end points in 31 selected trials were analyzed. OS was the pri-mary end point in 14 trials, and the secondary end point in 17. A time-to-event end point was the primaryend point in 8 studies, and the secondary end point in 22; the most reported time-to-event end points were composite end points, and the events changed among trials. A response end point was the primary end point in 9 studies, in 3 it was prostate-specifc antigen （PSA）-related, in 3 pain-related and in 3 mixed. A response end point was the secondary end point in 19 studies： PSA response and radiologic response were the most frequently used secondary end points in 19 and 11 tri-als, respectively, while pain response was used in 5 studies.CONCLUSION： A homogeneous defnition of progres-sion in future trials is mandatory. Among response end points, pain-response and PSA-response appear to be the most reliable.展开更多
文摘Recent results for synthesis of conjugated polymers, poly(arylene vinylene)s exemplified as poly(fluorene vinylene)s and poly(phenylene vinylene)s, by acyclic diene metathesis (ADMET) polymerization have been introduced. The methods using molybdenum and ruthenium catalysts afforded defect-free, high molecular weight polymers with all trans olefinic double bonds, and significant reduction of by-products (halogen, sulfur etc.) in addition of decrease of structurally defects have been attained. The methods also demonstrated precise synthesis of end-functionalized polymers that showed unique optical properties combined with the end groups. Catalytic one-pot syntheses of end-functionalized poly(9,9-dialkylfluorene-2,7-vinylene)s have been attained by both ruthenium (by chain-transfer) and molybdenum catalysts and the method should provide more green route for synthesis of conjugated materials with better device performance.
基金China Ocean Mineral Resources Research and Development under contract No.DY125-11-R-04the National Natural Science Foundation of China under contract No.41676036
文摘The carbonate-free fraction of 20 surface sediments collected from the ultraslow-spreading Southwest Indian Ridge(SWIR) was studied by grain size analysis and mineralogical analysis with X-ray powder diffraction(XRD),stereo microscopy and scanning electron microscopy(SEM). The characteristics of the carbonate-free fraction of the sediments were obtained, and related influential factors were discussed. The results show that the mean grain size of this fraction is in 1.96Φ–8.19Φ, with poorly sorting and unimodal, bimodal or irregular bimodal distribution patterns. Four grain size end members of the fraction are derived with the End Member Model method. The finest end member EM1 shows a significant contribution of terrigenous materials of the aeolian input and sediment carried by the bottom current. End member EM2 with medium size mainly reflects sediment of a siliceous bioclast origin. EM3 and EM4 are interpreted as representing the coarser volcanic materials related to bedrock weathering or volcanic activities. Multi-provenance is the dominant factor controlling the grain size pattern of the carbonate-free fraction of the sediments in that area. In addition, sediment transport processes such as the bottom current and wind are the minor factors that influence the grain size distribution of the carbonate-free fraction sediments.
文摘This study presents a laser-sheet imaging technique to measure the water surface of free overfalls with plunge pool. Varying the plunge pool length of a constant approach discharge created skimming, periodic oscillatory, and nappe flows. This study analyzes the resulting oscillating water surfaces and temporal variations of water stages at particular positions in the periodic oscillatory flow condition. The oscillation period and amplitude of temporal water stage variation were determined by directly measuring the time interval and water stage differences in water stage variations, respectively. The plunge pool length and air pocket characteristics seriously affected the periodic oscillatory flow. The oscillation period increased as the plunge pool length increased. On the other hand, the water stage amplitude decreased sharply when the plunge pool exceeded a specific length. The absence of an air pocket beneath the falling nappe significantly increased the oscillation period and decreased the water stage amplitude. This study investigates water surface oscillation in the plunge pool and the upstream side of the drop. However, the mean end depth of a periodic oscillatory flow with an air pocket is also applicable to discharge estimation using the end depth method.
文摘AIM： To review the defnition and performance of the commonly used end points in trials of systemic thera-pies in metastatic castration-resistant prostate cancer patients. METHODS： A literature search was undertaken on PubMed database to identify studies meeting estab-lished criteria, with the aim of selecting randomized clinical trials and study definition and performance of their end points. The end points were grouped into three categories： overall survival （OS）, time-to-event end points, and response end points. A special analysis was performed for secondary end points of the studies which documented a beneft in OS in the experimental arm. Finally, publishes analyses for surrogacy of the in-cluded end points were also reported. RESULTS： OS, time-to-event and response end points in 31 selected trials were analyzed. OS was the pri-mary end point in 14 trials, and the secondary end point in 17. A time-to-event end point was the primaryend point in 8 studies, and the secondary end point in 22; the most reported time-to-event end points were composite end points, and the events changed among trials. A response end point was the primary end point in 9 studies, in 3 it was prostate-specifc antigen （PSA）-related, in 3 pain-related and in 3 mixed. A response end point was the secondary end point in 19 studies： PSA response and radiologic response were the most frequently used secondary end points in 19 and 11 tri-als, respectively, while pain response was used in 5 studies.CONCLUSION： A homogeneous defnition of progres-sion in future trials is mandatory. Among response end points, pain-response and PSA-response appear to be the most reliable.
