Effects of polycarboxylate type admixture(PCA)on calcium monocarboaluminate hydrate(AFmc)formation in hydrated cement paste containing limestone filler(LF)are investigated by the Fourier transform infrared spect...Effects of polycarboxylate type admixture(PCA)on calcium monocarboaluminate hydrate(AFmc)formation in hydrated cement paste containing limestone filler(LF)are investigated by the Fourier transform infrared spectroscopy(FTIR),the scanning electron microscopy(SEM),the derivative thermogravimetric(DTG)analysis and the adsorption amount measurement.Experimental results indicate that AFmc forms during the initial hydration period of cement as early as 15 min.It is found that PCA accelerates the early age AFmc formation and enhances cement hydration by promoting C4AF hydration at the early age,and,as a consequence,the iron associated AFmc phase forms more readily.The phenomenon is not observed when PCA is replaced by a naphthalene formaldehyde sulphonate condensate water reducer.Compatibility between PCA and cement is modified due to the presence of AFmc along with ettringite(AFt),which results in a less adsorption amount of PCA on the surface of cement minerals.As a kind of high-range water reducer,PCA may be the preferred choice for concrete containing LF.展开更多
Objective: To study the pharmacokinetics of 20(R)-Ginsenoside Rg3 in the human body. Methods: High-performance liquid chromatography-ultraviolet detection method was used in this study. Results: The pharmacokinetics o...Objective: To study the pharmacokinetics of 20(R)-Ginsenoside Rg3 in the human body. Methods: High-performance liquid chromatography-ultraviolet detection method was used in this study. Results: The pharmacokinetics of Ginsenoside Rg3 in 14 healthy volunteers were investigated. After a single oral dose of 3.2 mg.g-1 Ginsenoside Rg3 in 8 male volunteers, the plasma concentration-time course fitted in well with a two-compartment open model, with the following pharmacokinetic parameters: Tmax 0.660.10 h, Cmax 166 ngmL-1, T1/2a 0.460.12 h, T1/2b 4.91.1 h, T1/2(Ka) 0.280.04 h, AUC0-∞ 7726 ngmL-1h, respectively. No kinetic analysis was made after an oral dose of 0.8 mg.g-1 Rg3 in other 6 volunteers because of the low concentration, but there was a good correlation between Cmax and dosage of the two groups. Conclusion: The absorption of Rg3 was rapid in the human body, and its elimination was rapid too after oral administration of Ginsenoside Rg3. The pharmacokinetic results shows that it exhibited the first-order kinetic characteristics.展开更多
An account of recent work on supported single‐atom catalyst design is given here for reactions as diverse as the low‐temperature water‐gas shift,methanol steam reforming,selective ethanol dehydrogenation,and select...An account of recent work on supported single‐atom catalyst design is given here for reactions as diverse as the low‐temperature water‐gas shift,methanol steam reforming,selective ethanol dehydrogenation,and selective hydrogenation of alkynes and dienes.It is of fundamental interest to investigate the intrinsic activity and selectivity of the active metal atom site and compare them to the properties of the corresponding metal nanoparticles and sub‐nm clusters.It is also important to understand what constitutes a stable active metal atom site in the various reaction environments,and maximize their loadings to allow us to design robust catalysts for industrial applications.Combined activity and stability studies,ideally following the evolution of the active site as a function of catalyst treatment in real time are recommended.Advanced characterization methods with atomic resolution will play a key role here and will be used to guide the design of new catalysts.展开更多
Objective: Panitumumab administered as monotherapy in colorectal cancer(CRC) has shown response and disease stabilization rates of approximately 30%. The current study aimed to evaluate the progression-free survival(P...Objective: Panitumumab administered as monotherapy in colorectal cancer(CRC) has shown response and disease stabilization rates of approximately 30%. The current study aimed to evaluate the progression-free survival(PFS) and overall survival(OS) of patients with metastatic colorectal cancer(mCRC) treated with panitumumab every 3 weeks as a second line treatment.Methods: This study is a retrospective analysis of 18 patients, aged more than 18 years, with wild-type KRAS exon 2 mCRC treated with panitumumab as a second-line single agent after progression on first-line chemotherapy.Results: The median number of courses received was 10(range, 4-29), and the median duration of treatment was 30 weeks(range,12-96 weeks). After a median follow-up period of 13 months, the median PFS was 6 months(range, 4.3-7.7 months) and the median OS was 11 months(range, 7.4-14.5 months). The median PFS was 4 months for patients with < grade 2 skin toxicity and 6months(range, 4.5-7.5 months) for patients with ≥ grade 2 skin rash(P=0.05). The median OS was 9 months(range, 6.4-11.5months) and 14 months(range, 11.6-16.3 months) for the two groups of patients(P=0.002).Conclusions: Panitumumab given every 3 weeks is effective and well tolerated in patients with advanced CRC that progressed after standard chemotherapy.展开更多
The existence of nanographene in cluster form is discussed in organic solvents. Theories are developed based on the columnlet, bundlet and droplet models describing the size-distribution functions. Phenomena present a...The existence of nanographene in cluster form is discussed in organic solvents. Theories are developed based on the columnlet, bundlet and droplet models describing the size-distribution functions. Phenomena present a unified explanation in the columnlet model in which free energy of Cgraphene involved in cluster is combined from a volume part proportional to the number of molecules n in cluster and a constant. The columnlet model enables describing distribution function of Cgraphene clusters by size. From purely geometrical considerations the columnlet (Cgraphene), bundlet (single-wall carbon nanotube), CNT (carbon nanotube), SWNT (single-wall C-nanotube), and carbon nanobud, CNB (carbon nanobud)) and droplet (fullerene) models predict dissimilar behaviours. The interaction-energy parameters of Cgraphene are taken from C60. An CNB behaviour or further is expected. The decay of solubility with rising temperature is smaller for Cgraphene than for SWNT and CNB and, furthermore, than for C60, in agreement with lesser numbers of units in Cgraphene clusters. The discrepancy between the experimental data of the heat of solution of fullerenes, CNTs, CNBs and graphenes is ascribed to the sharp concentration dependence of the heat of solution. The diffusion coefficient drops with temperature result greater for Cgraphene than CNB and SWNT than C60 corresponding to lesser number of units in clusters. The aggregates near (C60)13, SWNT/CNB7 and (Cgraphene)3 could be representative of the droplet, bundlet and columnlet models.展开更多
Regulating the selectivity of catalysts in selective hydrogenation reactions at the atomic level is highly desirable but remains a grand challenge. Here we report a simple and practical strategy to synthesize a monoli...Regulating the selectivity of catalysts in selective hydrogenation reactions at the atomic level is highly desirable but remains a grand challenge. Here we report a simple and practical strategy to synthesize a monolithic single-atom catalyst(SAC) with isolated Pd atoms supported on bulk nitrogen-doped carbon foams(Pd-SAs/CNF). Moreover, we demonstrate that the single-atom Pd sites with unique electronic structure endow Pd-SAs/CNF with an isolated site effect, leading to excellent activity and selectivity in 4-nitrophenylacetylene semi-hydrogenation reaction. In addition, benefiting from the great integrity and excellent mechanical strength, monolithic Pd-SAs/CNF catalyst is easy to separate from the reaction system for conducting the subsequent recycling. The cyclic test demonstrates the excellent reusability and stability of monolithic Pd-SAs/CNF catalyst.The discovery of isolated site effect provides a new approach to design highly selective catalysts. And the development of monolithic SACs provides new opportunities to advance the practical applications of single-atom catalysts.展开更多
We propose a method which uses functional singular component to establish functional additive models. The proposed methodology reduces the curve regression problem to ordinary(i.e., scalar) additive regression problem...We propose a method which uses functional singular component to establish functional additive models. The proposed methodology reduces the curve regression problem to ordinary(i.e., scalar) additive regression problems of the singular components of the predictor process and response process. Consistency of estimators for the nonparametric function and prediction are proved, respectively. A simulation study is conducted to investigate the finite sample performances of the proposed estimators.展开更多
基金The Natural Science Foundation of Jiangsu Province(No.BK2009712)the National Construction Research Project(No.2009-K4-9)
文摘Effects of polycarboxylate type admixture(PCA)on calcium monocarboaluminate hydrate(AFmc)formation in hydrated cement paste containing limestone filler(LF)are investigated by the Fourier transform infrared spectroscopy(FTIR),the scanning electron microscopy(SEM),the derivative thermogravimetric(DTG)analysis and the adsorption amount measurement.Experimental results indicate that AFmc forms during the initial hydration period of cement as early as 15 min.It is found that PCA accelerates the early age AFmc formation and enhances cement hydration by promoting C4AF hydration at the early age,and,as a consequence,the iron associated AFmc phase forms more readily.The phenomenon is not observed when PCA is replaced by a naphthalene formaldehyde sulphonate condensate water reducer.Compatibility between PCA and cement is modified due to the presence of AFmc along with ettringite(AFt),which results in a less adsorption amount of PCA on the surface of cement minerals.As a kind of high-range water reducer,PCA may be the preferred choice for concrete containing LF.
文摘Objective: To study the pharmacokinetics of 20(R)-Ginsenoside Rg3 in the human body. Methods: High-performance liquid chromatography-ultraviolet detection method was used in this study. Results: The pharmacokinetics of Ginsenoside Rg3 in 14 healthy volunteers were investigated. After a single oral dose of 3.2 mg.g-1 Ginsenoside Rg3 in 8 male volunteers, the plasma concentration-time course fitted in well with a two-compartment open model, with the following pharmacokinetic parameters: Tmax 0.660.10 h, Cmax 166 ngmL-1, T1/2a 0.460.12 h, T1/2b 4.91.1 h, T1/2(Ka) 0.280.04 h, AUC0-∞ 7726 ngmL-1h, respectively. No kinetic analysis was made after an oral dose of 0.8 mg.g-1 Rg3 in other 6 volunteers because of the low concentration, but there was a good correlation between Cmax and dosage of the two groups. Conclusion: The absorption of Rg3 was rapid in the human body, and its elimination was rapid too after oral administration of Ginsenoside Rg3. The pharmacokinetic results shows that it exhibited the first-order kinetic characteristics.
基金financial support of the work by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under Awards Grant Number DE-FG02-05ER15730
文摘An account of recent work on supported single‐atom catalyst design is given here for reactions as diverse as the low‐temperature water‐gas shift,methanol steam reforming,selective ethanol dehydrogenation,and selective hydrogenation of alkynes and dienes.It is of fundamental interest to investigate the intrinsic activity and selectivity of the active metal atom site and compare them to the properties of the corresponding metal nanoparticles and sub‐nm clusters.It is also important to understand what constitutes a stable active metal atom site in the various reaction environments,and maximize their loadings to allow us to design robust catalysts for industrial applications.Combined activity and stability studies,ideally following the evolution of the active site as a function of catalyst treatment in real time are recommended.Advanced characterization methods with atomic resolution will play a key role here and will be used to guide the design of new catalysts.
文摘Objective: Panitumumab administered as monotherapy in colorectal cancer(CRC) has shown response and disease stabilization rates of approximately 30%. The current study aimed to evaluate the progression-free survival(PFS) and overall survival(OS) of patients with metastatic colorectal cancer(mCRC) treated with panitumumab every 3 weeks as a second line treatment.Methods: This study is a retrospective analysis of 18 patients, aged more than 18 years, with wild-type KRAS exon 2 mCRC treated with panitumumab as a second-line single agent after progression on first-line chemotherapy.Results: The median number of courses received was 10(range, 4-29), and the median duration of treatment was 30 weeks(range,12-96 weeks). After a median follow-up period of 13 months, the median PFS was 6 months(range, 4.3-7.7 months) and the median OS was 11 months(range, 7.4-14.5 months). The median PFS was 4 months for patients with < grade 2 skin toxicity and 6months(range, 4.5-7.5 months) for patients with ≥ grade 2 skin rash(P=0.05). The median OS was 9 months(range, 6.4-11.5months) and 14 months(range, 11.6-16.3 months) for the two groups of patients(P=0.002).Conclusions: Panitumumab given every 3 weeks is effective and well tolerated in patients with advanced CRC that progressed after standard chemotherapy.
文摘The existence of nanographene in cluster form is discussed in organic solvents. Theories are developed based on the columnlet, bundlet and droplet models describing the size-distribution functions. Phenomena present a unified explanation in the columnlet model in which free energy of Cgraphene involved in cluster is combined from a volume part proportional to the number of molecules n in cluster and a constant. The columnlet model enables describing distribution function of Cgraphene clusters by size. From purely geometrical considerations the columnlet (Cgraphene), bundlet (single-wall carbon nanotube), CNT (carbon nanotube), SWNT (single-wall C-nanotube), and carbon nanobud, CNB (carbon nanobud)) and droplet (fullerene) models predict dissimilar behaviours. The interaction-energy parameters of Cgraphene are taken from C60. An CNB behaviour or further is expected. The decay of solubility with rising temperature is smaller for Cgraphene than for SWNT and CNB and, furthermore, than for C60, in agreement with lesser numbers of units in Cgraphene clusters. The discrepancy between the experimental data of the heat of solution of fullerenes, CNTs, CNBs and graphenes is ascribed to the sharp concentration dependence of the heat of solution. The diffusion coefficient drops with temperature result greater for Cgraphene than CNB and SWNT than C60 corresponding to lesser number of units in clusters. The aggregates near (C60)13, SWNT/CNB7 and (Cgraphene)3 could be representative of the droplet, bundlet and columnlet models.
基金supported by the National Key R&D Program of China (2018YFA0702003)the National Natural Science Foundation of China (21890383,21671117,21871159 and 21901135)+1 种基金the National Postdoctoral Program for Innovative Talents (BX20180160)the China Postdoctoral Science Foundation (2018M640113)。
文摘Regulating the selectivity of catalysts in selective hydrogenation reactions at the atomic level is highly desirable but remains a grand challenge. Here we report a simple and practical strategy to synthesize a monolithic single-atom catalyst(SAC) with isolated Pd atoms supported on bulk nitrogen-doped carbon foams(Pd-SAs/CNF). Moreover, we demonstrate that the single-atom Pd sites with unique electronic structure endow Pd-SAs/CNF with an isolated site effect, leading to excellent activity and selectivity in 4-nitrophenylacetylene semi-hydrogenation reaction. In addition, benefiting from the great integrity and excellent mechanical strength, monolithic Pd-SAs/CNF catalyst is easy to separate from the reaction system for conducting the subsequent recycling. The cyclic test demonstrates the excellent reusability and stability of monolithic Pd-SAs/CNF catalyst.The discovery of isolated site effect provides a new approach to design highly selective catalysts. And the development of monolithic SACs provides new opportunities to advance the practical applications of single-atom catalysts.
基金supported by National Natural Science Foundation of China (Grant Nos. 11171331, 11561006, 11331011)Program for Creative Research Group of National Natural Science Foundation of China (Grant No. 61621003)+4 种基金a Grant from the Key Lab of Random Complex Structure and Data Science, Chinese Academy of Sciencesthe Natural Science Foundation of Shenzhen UniversityResearch Projects of Colleges and Universities in Guangxi (Grant No. KY2015YB171)Innovation Project of Guangxi Graduate Education (Grant No. JGY2015122)a Grant from the Key Base of Humanities and Social Sciences in Guangxi College
文摘We propose a method which uses functional singular component to establish functional additive models. The proposed methodology reduces the curve regression problem to ordinary(i.e., scalar) additive regression problems of the singular components of the predictor process and response process. Consistency of estimators for the nonparametric function and prediction are proved, respectively. A simulation study is conducted to investigate the finite sample performances of the proposed estimators.