A copper-based non-aqueous-phase desulfurization agent is prepared by adding CuCl_(2) to the solvent N,Ndimethylformamide(DMF).Static desulfurization experiments show that the agent has high efficiency.However,the des...A copper-based non-aqueous-phase desulfurization agent is prepared by adding CuCl_(2) to the solvent N,Ndimethylformamide(DMF).Static desulfurization experiments show that the agent has high efficiency.However,the desulfurization reaction leads to the formation of a copper sulfide precipitate.It is found that the addition of chloride ions in the form of hydrochloric acid or potassium chloride prevents the formation of copper sulfide,and elemental sulfur is precipitated instead.The efficient absorption of H2S by the Cu/HCl–DMF agent relies on the rapid coordination of Cu^(2+)with DMF,Cl^(−),and H2S molecules to form a[Cu(DMF)_(n−p)(HS−)_(p)(Cl−)_(m)]_((2−p−m))+complex.The desulfurization agent has a sulfur capacity of up to 9.81 g/L when used in static bubble desulfurization at atmospheric pressure.The system has low viscosity and good chemical and thermal stability.It can be rapidly regenerated through continuous oxidation.After five repetitions of the regeneration procedure,the sulfur capacity reaches more than 91%of the initial capacity,indicating the potential of the system for commercial applications.展开更多
In this experiment,an EG/ChCl deep eutectic solvent(DES)was synthesized using choline chloride(ChCl)and ethylene glycol(EG)as the raw materials.The synthesized DES was characterized by Fourier transform infrared spect...In this experiment,an EG/ChCl deep eutectic solvent(DES)was synthesized using choline chloride(ChCl)and ethylene glycol(EG)as the raw materials.The synthesized DES was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.The results demonstrate the successful synthesis of DES.A certain amount of FeCl_(3) and CuSO_(4) was added to the DES to promote the absorption of H_(2)S;thus,a Fe(Ⅲ)-Cu(Ⅱ)coupled DES desulfurization system was obtained.The effects of DES raw materials’ratio,FeCl_(3) concentration,water content,CuSO_(4) concentration,and reaction temperature on the desulfurization efficiency and the regeneration conditions were studied.The results show that ChCl/EG DES with a molar ratio of 1:2 has a better desulfurization effect,and the addition of an appropriate amount of water can effectively promote the dissolution of CuSO_(4) and the absorption of H_(2)S.An appropriate increase in reaction temperature and CuSO_(4) concentration would also promote the absorption of H_(2)S.When the concentration of CuSO_(4) in DES desulfurizer was 0.15 mol/L,the gas speed was 20 mL/min,and the sulfur capacity could reach 10.23 g/L.The desulfurizer could be regenerated by passing O_(2),and the desulfurization efficiency did not change much after repeated use of desulfurization-regeneration many times.The desulfurization product was characterized by XRD as rhombohedral sulfur.展开更多
Background Mycophenolic acid （MPA） as an anti-proliferative immune-suppressive agent is used in the majority of immunosuppressive regimens in solid organ transplantation. This study aimed to investigate the pharmaco...Background Mycophenolic acid （MPA） as an anti-proliferative immune-suppressive agent is used in the majority of immunosuppressive regimens in solid organ transplantation. This study aimed to investigate the pharmacokinetic （PK） characteristics of enteric-coated mycophenolate sodium （EC-MPS） and area under the curve （AUC） from 0 to 12 hours with limited sampling strategies （LSSs） in Chinese renal transplant recipients. Methods This study was conducted in 10 Chinese renal transplant patients receiving living donor and treated with EC-MPS, cyclosporine, and corticosteroids. MPA concentrations were measured by enzyme multiplied immunoassay technique （EMIT）. Whole 12-hour PK profiles were obtained on Day 4 after operation. LSSs with jackknife technique, multiple stepwise regression analysis, and Bland-Altman analysis were developed to estimate MPAAUC. Results The mean maximum plasma concentration, the mean time for it to reach peak （Tmax）, and the mean MPA AUC were （11.38±2.49） mg/L, （4.85±3.32） hours, and （63.19±13.54） mg.h.L1, respectively. Among the 10 profiles, MPA AUC of four patients was significantly higher than that of the other six patients, and the corresponding Tmax was significantly longer than that of the other six patients. No patient exhibited a second peak caused by enterohepatic recirculation. The best models were as follows： 27.46＋0.94C3＋3.24C8＋2.81C10 （f2=0.972）, which was used to predict AUC of fast metabolizer with a mean prediction error （MPE） of -0.21% and a mean absolute prediction error （MAE） of 2.59%; 36.65＋3.08Ce＋5.30C10-4.04C12 （r2=0.992）, which was used to predict AUC of slow metabolizer with a MPE of 0.58% and a MAE of 1.95%. Conclusions The PKs of EC-MPS had a high variability among Chinese renal transplant recipients. The preliminary PK data indicated the existence of slow and fast metabolizer. These findings may be associated with the enterohepatic rec.irculation.展开更多
The inferior mirage from road surfaces is a common phenomenon,which can be easily seen in everyday life.It has been recognized in the literature as a light refraction phenomenon due to the refractive index gradient ca...The inferior mirage from road surfaces is a common phenomenon,which can be easily seen in everyday life.It has been recognized in the literature as a light refraction phenomenon due to the refractive index gradient caused by the temperature gradient in the air strata above the road surfaces.However,it was also suggested that the mirage is just a phenomenon of specular reflection at grazing incidence.Because of the lack of reasonable and quantitative evidence,the generally accepted light refraction theory has not yet been refuted.Here we show some mirror-like reflection images captured from a road surface stretch in Yujiashan North Road,Wuhan,China,when there was no obvious temperature gradient on or above the road,measured on a winter day in December 2009.This provided direct evidence to doubt the temperature induced light refraction mechanism of the inferior mirage.Furthermore,the critical grazing angle of about 0.2° to the road plane where the mirror-like reflection appears could not make the rough surface scatter incident light as a smooth surface according to the Rayleigh criterion.Therefore the phenomenon is a mirrorlike observation effect of scattering from the surface,which cannot be entirely explained by light refraction via air strata.The results demonstrate that the image-formation mechanism and the observer-based-analysis method shown here potentially offer a means of understanding a wide range of scattering phenomena from rough surfaces at grazing angle;for example,the superior mirages of unusual brightness occasionally observed over frozen lakes and the off-specular reflection phenomenon.展开更多
基金the China National Science and Technology Major Project(2016ZX05017)the Sinopec Group Corporation 2020 Science and Technology Project“Organic Sulfur Catalytic Hydrolysis Technology Improves Quality Research”(No.120049-1).
文摘A copper-based non-aqueous-phase desulfurization agent is prepared by adding CuCl_(2) to the solvent N,Ndimethylformamide(DMF).Static desulfurization experiments show that the agent has high efficiency.However,the desulfurization reaction leads to the formation of a copper sulfide precipitate.It is found that the addition of chloride ions in the form of hydrochloric acid or potassium chloride prevents the formation of copper sulfide,and elemental sulfur is precipitated instead.The efficient absorption of H2S by the Cu/HCl–DMF agent relies on the rapid coordination of Cu^(2+)with DMF,Cl^(−),and H2S molecules to form a[Cu(DMF)_(n−p)(HS−)_(p)(Cl−)_(m)]_((2−p−m))+complex.The desulfurization agent has a sulfur capacity of up to 9.81 g/L when used in static bubble desulfurization at atmospheric pressure.The system has low viscosity and good chemical and thermal stability.It can be rapidly regenerated through continuous oxidation.After five repetitions of the regeneration procedure,the sulfur capacity reaches more than 91%of the initial capacity,indicating the potential of the system for commercial applications.
基金China National Science and Technology Major Project(2016ZX05017)Sinopec Group Corporation 2020 Science and Technology Project“Organic Sulfur Catalytic Hydrolysis Technology Improves Quality Research”(No.120049-1).
文摘In this experiment,an EG/ChCl deep eutectic solvent(DES)was synthesized using choline chloride(ChCl)and ethylene glycol(EG)as the raw materials.The synthesized DES was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.The results demonstrate the successful synthesis of DES.A certain amount of FeCl_(3) and CuSO_(4) was added to the DES to promote the absorption of H_(2)S;thus,a Fe(Ⅲ)-Cu(Ⅱ)coupled DES desulfurization system was obtained.The effects of DES raw materials’ratio,FeCl_(3) concentration,water content,CuSO_(4) concentration,and reaction temperature on the desulfurization efficiency and the regeneration conditions were studied.The results show that ChCl/EG DES with a molar ratio of 1:2 has a better desulfurization effect,and the addition of an appropriate amount of water can effectively promote the dissolution of CuSO_(4) and the absorption of H_(2)S.An appropriate increase in reaction temperature and CuSO_(4) concentration would also promote the absorption of H_(2)S.When the concentration of CuSO_(4) in DES desulfurizer was 0.15 mol/L,the gas speed was 20 mL/min,and the sulfur capacity could reach 10.23 g/L.The desulfurizer could be regenerated by passing O_(2),and the desulfurization efficiency did not change much after repeated use of desulfurization-regeneration many times.The desulfurization product was characterized by XRD as rhombohedral sulfur.
文摘Background Mycophenolic acid （MPA） as an anti-proliferative immune-suppressive agent is used in the majority of immunosuppressive regimens in solid organ transplantation. This study aimed to investigate the pharmacokinetic （PK） characteristics of enteric-coated mycophenolate sodium （EC-MPS） and area under the curve （AUC） from 0 to 12 hours with limited sampling strategies （LSSs） in Chinese renal transplant recipients. Methods This study was conducted in 10 Chinese renal transplant patients receiving living donor and treated with EC-MPS, cyclosporine, and corticosteroids. MPA concentrations were measured by enzyme multiplied immunoassay technique （EMIT）. Whole 12-hour PK profiles were obtained on Day 4 after operation. LSSs with jackknife technique, multiple stepwise regression analysis, and Bland-Altman analysis were developed to estimate MPAAUC. Results The mean maximum plasma concentration, the mean time for it to reach peak （Tmax）, and the mean MPA AUC were （11.38±2.49） mg/L, （4.85±3.32） hours, and （63.19±13.54） mg.h.L1, respectively. Among the 10 profiles, MPA AUC of four patients was significantly higher than that of the other six patients, and the corresponding Tmax was significantly longer than that of the other six patients. No patient exhibited a second peak caused by enterohepatic recirculation. The best models were as follows： 27.46＋0.94C3＋3.24C8＋2.81C10 （f2=0.972）, which was used to predict AUC of fast metabolizer with a mean prediction error （MPE） of -0.21% and a mean absolute prediction error （MAE） of 2.59%; 36.65＋3.08Ce＋5.30C10-4.04C12 （r2=0.992）, which was used to predict AUC of slow metabolizer with a MPE of 0.58% and a MAE of 1.95%. Conclusions The PKs of EC-MPS had a high variability among Chinese renal transplant recipients. The preliminary PK data indicated the existence of slow and fast metabolizer. These findings may be associated with the enterohepatic rec.irculation.
基金supported by the National Natural Science Foundation of China(50636010,50721005)the Program of Introducing Talents of Discipline to Universities of China(B06019)
文摘The inferior mirage from road surfaces is a common phenomenon,which can be easily seen in everyday life.It has been recognized in the literature as a light refraction phenomenon due to the refractive index gradient caused by the temperature gradient in the air strata above the road surfaces.However,it was also suggested that the mirage is just a phenomenon of specular reflection at grazing incidence.Because of the lack of reasonable and quantitative evidence,the generally accepted light refraction theory has not yet been refuted.Here we show some mirror-like reflection images captured from a road surface stretch in Yujiashan North Road,Wuhan,China,when there was no obvious temperature gradient on or above the road,measured on a winter day in December 2009.This provided direct evidence to doubt the temperature induced light refraction mechanism of the inferior mirage.Furthermore,the critical grazing angle of about 0.2° to the road plane where the mirror-like reflection appears could not make the rough surface scatter incident light as a smooth surface according to the Rayleigh criterion.Therefore the phenomenon is a mirrorlike observation effect of scattering from the surface,which cannot be entirely explained by light refraction via air strata.The results demonstrate that the image-formation mechanism and the observer-based-analysis method shown here potentially offer a means of understanding a wide range of scattering phenomena from rough surfaces at grazing angle;for example,the superior mirages of unusual brightness occasionally observed over frozen lakes and the off-specular reflection phenomenon.
