The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropan...The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropanol,n-butanol,toluene,dichloromethane,chloroform,tetrachloromethane,1,2-dichloroethane,acetone,ethyl acetate,acetonitrile,N-methylpyrrolidone(NMP),N,Ndimethylformamide dimethyl sulfoxide(DMF),dimethyl sulfoxide(DMSO).The solubility of TCDNB could be increased with increasing temperature in fifteen mono-solvents.TCDNB solubility is in the following order at 298.15 K:NMP>DMF>DMSO>toluene>acetone>ethyl acetate>dichloromethane>1,2-dich loroethane>chloroform>acetonitrile>tetrachloromethane>methanol>ethanol>n-butanol>isopropanol.The KAT-LSER model was used to investigate the solvent effect,which revealed that the hydrogen bond acidity of solvents has a greater effect on TCDNB solubility.The van't Hoff model,the modified Apelblat model,theλh model,and the non-random two liquid(NRTL)model were used to correlate the solubility of TCDNB.The calculated solubility data agreed well with the experimental data,and the modified Apelblat model fit best.Furthermore,the van't Hoff and Gibbs equations were also used to calculate the dissolution thermodynamic properties of TCDNB in various solvents.TCDNB dissolution could be an enthalpy-driven,non-spontaneous,and endothermic process in fifteen mono-solvents.The determination and fitting solubility of TCDNB,as well as the calculation of its thermodynamic properties,would be critical in the purification and crystallization of its preparation process research.展开更多
Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich salin...Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich saline would promote the repair of spinal cord injury induced by Allen's method in rats. At 0.5, 1, 2, 4, 8, 12 and 24 hours after injury, then once daily for 2 weeks, 0.25 mL/kg hydrogen-rich saline was infused into the subarachnoid space through a catheter. Results at 24 hours, 48 hours, 1 week and 2 weeks after injury showed that hydrogen-rich saline markedly reduced cell death, inflammatory cell infiltration, serum malondialdehyde content, and caspa se-3 immunoreactivity, elevated serum superoxide dismutase activity and calcitonin gene-related peptide immunoreactivity, and improved motor function in the hindlimb. The present study confirms that hydrogen-rich saline injected within 2 weeks of injury effectively contributes to the repair of spinal cord injury in the acute stage.展开更多
The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent years.Sulfadiazine(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving w...The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent years.Sulfadiazine(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving water body.In this paper,gamma rays are used to irradiate samples of sulfadiazine antibiotics-containing wastewater.The results demonstrate that SD can be effectively degraded by irradiation,but the mineralization degree of SD(in terms of TOC) is not as efficient as the SD degradation.The addition of Fe^(2+) can significantly enhance the SD degradation and mineralization through the generation of hydroxyl radical by catalytic decomposition of H_2O_2 from water radiolysis.Ion chromatography analysis indicates that sulfate ions(SO_4^(2-)) and formate(HCOO^-) are the main intermediate products.Gamma irradiation is a promising technology for removing low-concentration antibiotics from water and wastewater.展开更多
Computations by density functional theory(DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation(HOF) is predicted by the designed iso...Computations by density functional theory(DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation(HOF) is predicted by the designed isodesmic reactions. The predicted results reveal that eN 3and eN ]Ne groups are effective structural units for increasing the HOF values of the di-1H-1,3,4-triazole derivatives. The HOMOe LUMO gap is affected by the substituents and linkage groups. Detonation performance is evaluated using the Kamlete Jacobs approach based on the calculated density and HOF. The results indicate that e NO2, e NF2, e NHe, e NHe NHe and e N]Ne groups are helpful for enhancing the detonation properties of di-1H-1,3,4-triazole derivatives. The bond dissociation energy and bond order of the weakest bonds are analyzed to investigate their stability. It is observed that the eC H2 e, e CH2 e CH2e and e CH]CHe groups are effective structural units for improving the stabilities of these derivatives. Considering the detonation performance and the stability, five compounds are screened as the potential candidates for high energy density materials.展开更多
The radiation-induced degradation of 4-nitrophenol(4-NP) was performed in combination with a Fenton reagent, H_2O_2, and Ti O_2 nanoparticles to investigate the synergetic effects of radiolytical degradation combined ...The radiation-induced degradation of 4-nitrophenol(4-NP) was performed in combination with a Fenton reagent, H_2O_2, and Ti O_2 nanoparticles to investigate the synergetic effects of radiolytical degradation combined with other advanced oxidation processes. The experimental results indicated that the degradation efficiency of 4-NP was 87.5, 57.4, and 41.0 % at a dose of 20 k Gy when its initial concentration was 100, 200, and 350 mg/L, respectively. Radiation combined with H_2O_2, the Fenton method,and Ti O_2 remarkably increased the degradation efficiency of 4-NP, showing the synergetic effects. Radiation may enhance the biodegradability of 4-NP, suggesting that it has the potential to be used as a pretreatment method in combination with the biological method for the treatment of industrial wastewater containing toxic organic pollutants. Major intermediates during the 4-NP degradation process were identified and a possible degradation pathway was tentatively proposed.展开更多
A novel magnetic chitosan bead cross-linked with glutaraldehyde was prepared, characterized and applied for Cs(I) removal from aqueous solution. Characteristics and mechanism of Cs(I) removal were investigated. The eq...A novel magnetic chitosan bead cross-linked with glutaraldehyde was prepared, characterized and applied for Cs(I) removal from aqueous solution. Characteristics and mechanism of Cs(I) removal were investigated. The equilibrium data of Cs(I) adsorption by magnetic chitosan beads were fitted using the Langmuir,Freundlich, Tempkin, Redlich–Peterson(R–P), Slips and Dubini–Radushkevich(D–R) models. The maximum adsorption capacity was estimated at 3.86 mg/g from the Langmuir isotherm. FTIR study revealed that N atom was mainly involved in Cs(I) sorption by magnetic chitosan.The magnetic chitosan is a promising adsorbing material for treating Cs(I)-containing radioactive wastewater.展开更多
BACKGROUND Several studies have proved the safety and feasibility of robot-assisted percutaneous coronary intervention(PCI)in reducing the occupational hazards of interventionists while achieving precision medicine.Ho...BACKGROUND Several studies have proved the safety and feasibility of robot-assisted percutaneous coronary intervention(PCI)in reducing the occupational hazards of interventionists while achieving precision medicine.However,an independently developed robot-assisted system for PCI in China has not yet emerged.This study aimed to evaluate the safety and feasibility of a robot-assisted system for elective PCI in China.METHODS This preclinical trial included 22 experimental pigs and preliminarily supported the safety and feasibility of the ETcath200 robot-assisted system for PCI.Then,eleven patients with coronary heart disease who met the inclusion criteria and had clinical indications for elective PCI were enrolled.PCI was performed using a robot-assisted system.The primary outcomes were clinical success(defined as visual estimated residual stenosis<30%after PCI and no major adverse cardiovascular events during hospitalization and within 30 days after PCI)and technical success(defined as the ability to use the robot-assisted system to complete PCI successfully without conversion to the traditional manual PCI).RESULTS Eleven patients were included in this clinical trial.A drug-eluting stent with a diameter of 3 mm(interquartile range:2.75–3.5 mm)and a length of 26 mm(interquartile range:22–28 mm)was deployed in all patients.The clinical success rate was 100%,with no PCI-related complications and no in-hospital or 30-day major adverse cardiovascular events,and the technical success rate was 100%.CONCLUSIONS The results strongly suggest that the use of the independently developed robot-assisted system in China for elective PCI is feasible,safe,and effective.展开更多
BACKGROUND Tanscatheter left atrial appendage(LAA)closure and minimally invasive thoracoscopic LAA occlusion are local interventions of LAA for stroke prevention in patients with nonvalvular atrial fibrillation(NVAF)....BACKGROUND Tanscatheter left atrial appendage(LAA)closure and minimally invasive thoracoscopic LAA occlusion are local interventions of LAA for stroke prevention in patients with nonvalvular atrial fibrillation(NVAF).However,the safety and efficacy of these methods have not been compared.This prospective cohort study aimed to assess the safety and efficacy of those two treatment approaches for stroke prevention in NVAF patients.METHODS Two hundred and nine recurrent NVAF patients who received radiofrequency ablation were enrolled.These pa-tients were treated with transcatheter LAA closure or thoracoscopic LAA occlusion.The patients were followed up from the first postoperative day and evaluated for efficacy endpoints(stroke/transient ischemic attack(TIA),systemic embolism(SE),and death)and a safety endpoint(bleeding events).Perioperative complications were recorded.RESULTS After a median follow-up of 1.8 years(383 patient-years),the overall rate of the composite efficacy endpoints was similar between the two groups(3.8 vs.2.7 events per 100 patient-years;HR=0.71;95%CI:0.225−2.237;P=0.559).However,regarding primary safety endpoint,there were 1.5 bleeding events per 100 patient-years in the thoracoscopic LAA occlusion group,com-pared with 6.4 in transcatheter LAA closure group(HR=0.246;95%CI:0.074−0.819;P=0.022).The incidence of operative com-plications was 3/138(2.17%)in thoracoscopic LAA occlusion group and 1/71(1.41%)in transcatheter LAA closure group.CONCLUSIONS Thoracoscopic LAA occlusion and transcatheter LAA closure have similar efficacy in preventing stroke in NVAF patients.However,the thoracoscopic group had fewer bleeding events than the transcatheter group,but the former group required a longer hospital stay.展开更多
Excimer laser coronary angioplasty(ELCA)modifies atherosclerotic plaques through its photochemical,photothermal and photodynamic characteristics,while making up for the limitations of intimal disassembly and restenosi...Excimer laser coronary angioplasty(ELCA)modifies atherosclerotic plaques through its photochemical,photothermal and photodynamic characteristics,while making up for the limitations of intimal disassembly and restenosis of balloon angioplasty without causing significant damage.The American Food and Drug Administration approved of the first clinical application of ELCA in 1992.Since then,ELCA has been used as an adjunct therapy in the treatment of various subsets of coronary artery lesions.ELCA considered to be a relatively safe and effective technique for coronary lesions when routine angioplasty is technically insufficient.展开更多
Gamma ray-induced degradation of 2,4-dichlorophenol(DCP) in the presence of ozone has been investigated.The results show that ozone can remarkably increase the degradation rate of 2,4-DCP in aqueous solution.The degra...Gamma ray-induced degradation of 2,4-dichlorophenol(DCP) in the presence of ozone has been investigated.The results show that ozone can remarkably increase the degradation rate of 2,4-DCP in aqueous solution.The degradation kinetics of 2,4-DCP can be described by the first-order reaction model,and the rate constant was0.443,0.490 and 1.247 h^(-1),respectively,for γ-ray irradiation only,γ-ray irradiation+13 mg/L O_3 and γ-ray irradiation+30 mg/L O_3.High-performance liquid chromatography analysis shows that the dechlorinated products are 4-chlorophenol,2-chlorophenol and phenol;and the oxidation products are hydroquinone,benzoquinone,maleic,fumaric,acrylic,malonic,oxalic,acetic and formic acids.The possible pathways for 2,4-DCP degradation involving all these oxidation products are tentatively proposed.Combining γ-ray irradiation with ozonation is a promising technology for removing toxic pollutants from water and wastewater.展开更多
To investigate the oxidation of acenaphthene (Ace), a polycyclic aromatic hydrocarbon (PAH) with a saturated C-C bond by ozone and to characterize the intermediate products of ozonation. Methods Ozone was generate...To investigate the oxidation of acenaphthene (Ace), a polycyclic aromatic hydrocarbon (PAH) with a saturated C-C bond by ozone and to characterize the intermediate products of ozonation. Methods Ozone was generated from filtered dry oxygen by an ozone generator and continually bubbled into a reactor containing lg/L Ace dissolved in an acetonitrile/water solvent mixture (90/10, v/v) at a rate of 0.5 mg/s. HPLC was used to analyze the Ace concentration. Total organic carbon (TOC) was used to measure the amount of water soluble organic compounds. GC-MS was used to identify the ozonized products. Oxygen uptake rate (OUR) of activated sludge was used to characterize the biodegradability of ozonized products. Results During the ozonation process, Ace was degraded, new organic compounds were produced and these intermediate products were difficult mineralize by ozone, with increasing TOC of soluble organics. The ozonized products were degraded by activated sludge more easily than Ace. Conclusion Ozonation decomposes the Ace and improves its biodegradability. The ozonation combined with biological treatment is probably an efficient and economical way to mineralize acenaphthene in wastewater.展开更多
Objective To investigate reductive dechlorination of 4-chlorophenol (4-CP) by nanoscale Fe^0 under different conditions. Methods Nanoscale Fe^0 was synthesized by using reductive method. 4-CP and its intermediate pr...Objective To investigate reductive dechlorination of 4-chlorophenol (4-CP) by nanoscale Fe^0 under different conditions. Methods Nanoscale Fe^0 was synthesized by using reductive method. 4-CP and its intermediate products were analyzed by HPLC. Chlorine ion was quantified with DX-100 ion chromatograph. Nano-iron particles were observed under a FEI Quanta 200 FEG environmental scanning electron microscope (ESEM). Results The size of the particles was in the range of 10-100 nm. The nano-iron particles could reduce 4-CP effectively. The initial concentration of 4-CP increased with the decrease of the relative degradation rate, whereas the reduced amount of 4-CP increased. Temperature could influence both the dechlorination rate and the reaction pathway. Moreover, the stability and durability of nanoscale Fe^0 was evaluated through batch studies over extended periods of time. Conclusion The nanoscale Fe^0 can be used for sustainable treatment of contaminants in groundwater.展开更多
Objective To investigate the biodegradation of tetrachloroethylene (PCE) by acclimated anaerobic sludge using different co-substrates, i.e., glucose, acetate, and lactate as electron donors. Methods HP-6890 gas chro...Objective To investigate the biodegradation of tetrachloroethylene (PCE) by acclimated anaerobic sludge using different co-substrates, i.e., glucose, acetate, and lactate as electron donors. Methods HP-6890 gas chromatograph (GC) in combination with auto-sampler was used to analyze the concentration of PCE and its intermediates, Results PCE could be degraded by reductive dechlorlnation and the degradation reaction conformed to the first-order kinetic equation. The rate constants are klaetate〉kglucose〉kacetate. The PCE degradation rate was the highest in the presence of lactate as an electron donor. Conclusion Lactate is the most suitable electron donor for PCE degradation and the electron donors supplied by co-metabolic substrates are not the limiting factors for PCE degradation,展开更多
The generalized cell mapping(GCM) method is used to obtain the stationary response of a single-degree-of-freedom.Vibro-impact system under a colored noise excitation. In order to show the advantage of the GCM method, ...The generalized cell mapping(GCM) method is used to obtain the stationary response of a single-degree-of-freedom.Vibro-impact system under a colored noise excitation. In order to show the advantage of the GCM method, the stochastic averaging method is also presented. Both of the two methods are tested through concrete examples and verified by the direct numerical simulation. It is shown that the GCM method can well predict the stationary response of this noise-perturbed system no matter whether the noise is wide-band or narrow-band, while the stochastic averaging method is valid only for the wide-band noise.展开更多
Objective To investigate the biodegradation of tetrachloroethylene (PCE) using methanol as electron donor by acclimated anaerobic sludge. Methods HP-6890 gas chromatograph (GC), together with HP-7694 autosarnpler,...Objective To investigate the biodegradation of tetrachloroethylene (PCE) using methanol as electron donor by acclimated anaerobic sludge. Methods HP-6890 gas chromatograph (GC), together with HP-7694 autosarnpler, was used to analyze the concentration of PCE and intermediates. Results PCE could be decholrinated reductively to DCE via TCE, and probably further to VC and ethylene. The degradation of PCE and TCE conformed to first-order reaction kinetics. The reaction rate constants were 0.8991 d^-1 and 0.068 d^-1, respectively, and the corresponding half-life were 0.77 d and 10.19 d, respectively. TCE production rate constant was 0.1333 d^-1, showing that PCE was degraded more rapidly than TCE. Conclusion Methanol is an electron donor suitable for PCE degradation and the cometabolic electron donors are not limiting factors for PCE degradation.展开更多
Background: The European Society of Urogenital Radiology has built the Prostate Imaging Reporting and Data System (PI-RADS) for standardizing the diagnosis of prostate cancer (PCa). This study evaluated the PI-RA...Background: The European Society of Urogenital Radiology has built the Prostate Imaging Reporting and Data System (PI-RADS) for standardizing the diagnosis of prostate cancer (PCa). This study evaluated the PI-RADS diagnosis method in patients with prostate-specific antigen (PSA) 〈20 ng/ml. Methods: A total of 133 patients with PSA 〈20 ng/ml were prospectively recruited. T2-weighted (T2WI) and diffusion-weighted (DWI) magnetic resonance images of the prostate were acquired before a 12-core transrectal prostate biopsy. Each patient's peripheral zone was divided into six regions on the images; each region corresponded to two of the 12 biopsy cores. T2WI, DWI, and T2W1 + DWI scores were computed according to PI-RADS. The diagnostic accuracy of the PI-RADS score was evaluated using histopathology of prostate biopsies as the reference standard. Results: PCa was histologically diagnosed in 169 (21.2%) regions. Increased PI-RADS score correlated positively with increased cancer detection rate. The cancer detection rate for scores 1 to 5 was 2.8%, 15.0%, 34.6%, 52.6%, and 88.9%, respectively, using T2W1 and 12.0%, 20.2%, 48.0%, 85.7%, and 93.3%, respectively, using DWI. For T2WI + DWI, the cancer detection rate was 1.5% (score 2), 13.5% (scores 3-4), 41.3% (scores 5-6), 75.9% (scores 7-8), and 92.3% (scores 9-10). The area under the curve for cancer detection was 0.700 (T2WI), 0.735 (DWI) and 0.749 (T2WI + DWI). The sensitivity and specificity were 53.8% and 89.2%, respectively, when The summed score ofT2Wl + DWI展开更多
Background: High rate of in-stent restenosis (ISR) remained an unsolved clinical problem in clinical practice, especially among patients with diabetes mellitus (DM). Diabetic patients often had hypertriglyceridem...Background: High rate of in-stent restenosis (ISR) remained an unsolved clinical problem in clinical practice, especially among patients with diabetes mellitus (DM). Diabetic patients often had hypertriglyceridemia with elevated levels of very low-density lipoprotein cholesterol (VLDL-C). Increasing evidence suggested that VLDL-C was known as a significant risk factor for atherosclerosis and had been recommended as a treatment target by current dyslipidemia guidelines. However, the role of VLDL-C in the occurrence and development of ISR in coronary artery disease (CAD) patients with DM had not been studied. The aim of this study was to evaluate the association between the elevated levels of VLDL-C and the risk of ISR in CAD patients with DM. Methods: A total of 1390 diabetic patients, who underwent coronary drug-eluting stent (DES) implantation at Beijing Anzhen Hospital and followed up by angiography within 6–24 months, were consecutively enrolled. Patients' demographic and clinical characteristics, including age, gender, CAD risk factors, family history, life style, medical history, and coronary angiographic information, were collected carefully at baseline percutaneous coronary intervention and follow-up angiography. Multivariate Cox&#39;s proportional hazards regression modeling using the step-wise method (entry, 0.05; removal, 0.05) was used to determine the independent risk associated with ISR in diabetic patients. Results: Finally, 1206 of patients were included in this study. ISR occurred in 132/1206 diabetic patients (10.9%) by follow-up angiography. Patients with ISR had elevated median serum VLDL-C levels compared with those without ISR (0.65 mmol/L vs. 0.52 mmol/L, P = 0.030). The multivariate regression analysis showed that VLDL-C was significantly associated with the risk of ISR in diabetic CAD patients (hazard ratio [HR] = 1.15, 95% confidence interval [CI]: 1.03–1.29, P = 0.017). The HR for the risk of ISR associated with VLDL-C level ≥0.52 mmol/L was 3.01 (95% CI: 1.24–7.34, P = 0.015). Conclusion: The elevated level of serum VLDL-C was a significant and independent risk factor for ISR in diabetic CAD patients after coronary DES implantation.展开更多
文摘The solubility of 2,3,4-trichloro-1,5-dinitrobenzene(TCDNB) was measured by a laser dynamic method over the temperature range from 278.15 K to 323.15 K under 0.1 MPa in fifteen mono-solvents(methanol,ethanol,isopropanol,n-butanol,toluene,dichloromethane,chloroform,tetrachloromethane,1,2-dichloroethane,acetone,ethyl acetate,acetonitrile,N-methylpyrrolidone(NMP),N,Ndimethylformamide dimethyl sulfoxide(DMF),dimethyl sulfoxide(DMSO).The solubility of TCDNB could be increased with increasing temperature in fifteen mono-solvents.TCDNB solubility is in the following order at 298.15 K:NMP>DMF>DMSO>toluene>acetone>ethyl acetate>dichloromethane>1,2-dich loroethane>chloroform>acetonitrile>tetrachloromethane>methanol>ethanol>n-butanol>isopropanol.The KAT-LSER model was used to investigate the solvent effect,which revealed that the hydrogen bond acidity of solvents has a greater effect on TCDNB solubility.The van't Hoff model,the modified Apelblat model,theλh model,and the non-random two liquid(NRTL)model were used to correlate the solubility of TCDNB.The calculated solubility data agreed well with the experimental data,and the modified Apelblat model fit best.Furthermore,the van't Hoff and Gibbs equations were also used to calculate the dissolution thermodynamic properties of TCDNB in various solvents.TCDNB dissolution could be an enthalpy-driven,non-spontaneous,and endothermic process in fifteen mono-solvents.The determination and fitting solubility of TCDNB,as well as the calculation of its thermodynamic properties,would be critical in the purification and crystallization of its preparation process research.
基金supported by a grant from Hunan Provincial Science and Technology Ministry of China,No.2015JJ6116
文摘Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich saline would promote the repair of spinal cord injury induced by Allen's method in rats. At 0.5, 1, 2, 4, 8, 12 and 24 hours after injury, then once daily for 2 weeks, 0.25 mL/kg hydrogen-rich saline was infused into the subarachnoid space through a catheter. Results at 24 hours, 48 hours, 1 week and 2 weeks after injury showed that hydrogen-rich saline markedly reduced cell death, inflammatory cell infiltration, serum malondialdehyde content, and caspa se-3 immunoreactivity, elevated serum superoxide dismutase activity and calcitonin gene-related peptide immunoreactivity, and improved motor function in the hindlimb. The present study confirms that hydrogen-rich saline injected within 2 weeks of injury effectively contributes to the repair of spinal cord injury in the acute stage.
基金supported by the National Natural Science Foundation of China(No.51338005)
文摘The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent years.Sulfadiazine(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving water body.In this paper,gamma rays are used to irradiate samples of sulfadiazine antibiotics-containing wastewater.The results demonstrate that SD can be effectively degraded by irradiation,but the mineralization degree of SD(in terms of TOC) is not as efficient as the SD degradation.The addition of Fe^(2+) can significantly enhance the SD degradation and mineralization through the generation of hydroxyl radical by catalytic decomposition of H_2O_2 from water radiolysis.Ion chromatography analysis indicates that sulfate ions(SO_4^(2-)) and formate(HCOO^-) are the main intermediate products.Gamma irradiation is a promising technology for removing low-concentration antibiotics from water and wastewater.
文摘Computations by density functional theory(DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation(HOF) is predicted by the designed isodesmic reactions. The predicted results reveal that eN 3and eN ]Ne groups are effective structural units for increasing the HOF values of the di-1H-1,3,4-triazole derivatives. The HOMOe LUMO gap is affected by the substituents and linkage groups. Detonation performance is evaluated using the Kamlete Jacobs approach based on the calculated density and HOF. The results indicate that e NO2, e NF2, e NHe, e NHe NHe and e N]Ne groups are helpful for enhancing the detonation properties of di-1H-1,3,4-triazole derivatives. The bond dissociation energy and bond order of the weakest bonds are analyzed to investigate their stability. It is observed that the eC H2 e, e CH2 e CH2e and e CH]CHe groups are effective structural units for improving the stabilities of these derivatives. Considering the detonation performance and the stability, five compounds are screened as the potential candidates for high energy density materials.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT-13026)the National High Technology Research and Development Program (No. 2009AA063905)+1 种基金the International S&T Cooperation Program (ISTCP) of China (No. 2009DFB90600)the National Natural Science Foundation of China (No. 51338005)
文摘The radiation-induced degradation of 4-nitrophenol(4-NP) was performed in combination with a Fenton reagent, H_2O_2, and Ti O_2 nanoparticles to investigate the synergetic effects of radiolytical degradation combined with other advanced oxidation processes. The experimental results indicated that the degradation efficiency of 4-NP was 87.5, 57.4, and 41.0 % at a dose of 20 k Gy when its initial concentration was 100, 200, and 350 mg/L, respectively. Radiation combined with H_2O_2, the Fenton method,and Ti O_2 remarkably increased the degradation efficiency of 4-NP, showing the synergetic effects. Radiation may enhance the biodegradability of 4-NP, suggesting that it has the potential to be used as a pretreatment method in combination with the biological method for the treatment of industrial wastewater containing toxic organic pollutants. Major intermediates during the 4-NP degradation process were identified and a possible degradation pathway was tentatively proposed.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University (IRT-13026)the National S&T Major Project (2013ZX06002001)support provided by the National Natural Science Foundation of China (Grant No. 51338005)
文摘A novel magnetic chitosan bead cross-linked with glutaraldehyde was prepared, characterized and applied for Cs(I) removal from aqueous solution. Characteristics and mechanism of Cs(I) removal were investigated. The equilibrium data of Cs(I) adsorption by magnetic chitosan beads were fitted using the Langmuir,Freundlich, Tempkin, Redlich–Peterson(R–P), Slips and Dubini–Radushkevich(D–R) models. The maximum adsorption capacity was estimated at 3.86 mg/g from the Langmuir isotherm. FTIR study revealed that N atom was mainly involved in Cs(I) sorption by magnetic chitosan.The magnetic chitosan is a promising adsorbing material for treating Cs(I)-containing radioactive wastewater.
基金supported by the National Natural Science Foundation of China(No.7212027,No.7214223)the National Key Research and Development Program of China(2017YFC0908800)the Beijing Municipal Health Commission(PXM2020_026272_000002,PXM2020_026272_000014).
文摘BACKGROUND Several studies have proved the safety and feasibility of robot-assisted percutaneous coronary intervention(PCI)in reducing the occupational hazards of interventionists while achieving precision medicine.However,an independently developed robot-assisted system for PCI in China has not yet emerged.This study aimed to evaluate the safety and feasibility of a robot-assisted system for elective PCI in China.METHODS This preclinical trial included 22 experimental pigs and preliminarily supported the safety and feasibility of the ETcath200 robot-assisted system for PCI.Then,eleven patients with coronary heart disease who met the inclusion criteria and had clinical indications for elective PCI were enrolled.PCI was performed using a robot-assisted system.The primary outcomes were clinical success(defined as visual estimated residual stenosis<30%after PCI and no major adverse cardiovascular events during hospitalization and within 30 days after PCI)and technical success(defined as the ability to use the robot-assisted system to complete PCI successfully without conversion to the traditional manual PCI).RESULTS Eleven patients were included in this clinical trial.A drug-eluting stent with a diameter of 3 mm(interquartile range:2.75–3.5 mm)and a length of 26 mm(interquartile range:22–28 mm)was deployed in all patients.The clinical success rate was 100%,with no PCI-related complications and no in-hospital or 30-day major adverse cardiovascular events,and the technical success rate was 100%.CONCLUSIONS The results strongly suggest that the use of the independently developed robot-assisted system in China for elective PCI is feasible,safe,and effective.
基金Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support(code:ZYLX201303,XMLX201601)the grant from National Key Research and Development Program of China(2017YFC0908800).
文摘BACKGROUND Tanscatheter left atrial appendage(LAA)closure and minimally invasive thoracoscopic LAA occlusion are local interventions of LAA for stroke prevention in patients with nonvalvular atrial fibrillation(NVAF).However,the safety and efficacy of these methods have not been compared.This prospective cohort study aimed to assess the safety and efficacy of those two treatment approaches for stroke prevention in NVAF patients.METHODS Two hundred and nine recurrent NVAF patients who received radiofrequency ablation were enrolled.These pa-tients were treated with transcatheter LAA closure or thoracoscopic LAA occlusion.The patients were followed up from the first postoperative day and evaluated for efficacy endpoints(stroke/transient ischemic attack(TIA),systemic embolism(SE),and death)and a safety endpoint(bleeding events).Perioperative complications were recorded.RESULTS After a median follow-up of 1.8 years(383 patient-years),the overall rate of the composite efficacy endpoints was similar between the two groups(3.8 vs.2.7 events per 100 patient-years;HR=0.71;95%CI:0.225−2.237;P=0.559).However,regarding primary safety endpoint,there were 1.5 bleeding events per 100 patient-years in the thoracoscopic LAA occlusion group,com-pared with 6.4 in transcatheter LAA closure group(HR=0.246;95%CI:0.074−0.819;P=0.022).The incidence of operative com-plications was 3/138(2.17%)in thoracoscopic LAA occlusion group and 1/71(1.41%)in transcatheter LAA closure group.CONCLUSIONS Thoracoscopic LAA occlusion and transcatheter LAA closure have similar efficacy in preventing stroke in NVAF patients.However,the thoracoscopic group had fewer bleeding events than the transcatheter group,but the former group required a longer hospital stay.
基金This study was supported by the National Natural Science Foundation of China(No.7212027&No.7214223)National Key Research and Development Program of China(2017YFC0908800)and the Beijing Municipal Health Commission(PXM2020_026272_000002&PXM2020_026272_000014).
文摘Excimer laser coronary angioplasty(ELCA)modifies atherosclerotic plaques through its photochemical,photothermal and photodynamic characteristics,while making up for the limitations of intimal disassembly and restenosis of balloon angioplasty without causing significant damage.The American Food and Drug Administration approved of the first clinical application of ELCA in 1992.Since then,ELCA has been used as an adjunct therapy in the treatment of various subsets of coronary artery lesions.ELCA considered to be a relatively safe and effective technique for coronary lesions when routine angioplasty is technically insufficient.
基金supported by the National Natural Science Foundation of China(No.51338005)the Program for Changjiang Scholars and Innovative Research Team in University(IRT-13026)+1 种基金the National High Technology Research and Development Program(No.2009AA063905)the International S&T Cooperation Program(ISTCP)of China(No.2009DFB90600)
文摘Gamma ray-induced degradation of 2,4-dichlorophenol(DCP) in the presence of ozone has been investigated.The results show that ozone can remarkably increase the degradation rate of 2,4-DCP in aqueous solution.The degradation kinetics of 2,4-DCP can be described by the first-order reaction model,and the rate constant was0.443,0.490 and 1.247 h^(-1),respectively,for γ-ray irradiation only,γ-ray irradiation+13 mg/L O_3 and γ-ray irradiation+30 mg/L O_3.High-performance liquid chromatography analysis shows that the dechlorinated products are 4-chlorophenol,2-chlorophenol and phenol;and the oxidation products are hydroquinone,benzoquinone,maleic,fumaric,acrylic,malonic,oxalic,acetic and formic acids.The possible pathways for 2,4-DCP degradation involving all these oxidation products are tentatively proposed.Combining γ-ray irradiation with ozonation is a promising technology for removing toxic pollutants from water and wastewater.
基金The project was supported by the National Natural Science Foundation of China (Grant No. 50325824).
文摘To investigate the oxidation of acenaphthene (Ace), a polycyclic aromatic hydrocarbon (PAH) with a saturated C-C bond by ozone and to characterize the intermediate products of ozonation. Methods Ozone was generated from filtered dry oxygen by an ozone generator and continually bubbled into a reactor containing lg/L Ace dissolved in an acetonitrile/water solvent mixture (90/10, v/v) at a rate of 0.5 mg/s. HPLC was used to analyze the Ace concentration. Total organic carbon (TOC) was used to measure the amount of water soluble organic compounds. GC-MS was used to identify the ozonized products. Oxygen uptake rate (OUR) of activated sludge was used to characterize the biodegradability of ozonized products. Results During the ozonation process, Ace was degraded, new organic compounds were produced and these intermediate products were difficult mineralize by ozone, with increasing TOC of soluble organics. The ozonized products were degraded by activated sludge more easily than Ace. Conclusion Ozonation decomposes the Ace and improves its biodegradability. The ozonation combined with biological treatment is probably an efficient and economical way to mineralize acenaphthene in wastewater.
基金The work was supported by the National Natural Science Foundation of China (Grant No. 50325824 50678089).
文摘Objective To investigate reductive dechlorination of 4-chlorophenol (4-CP) by nanoscale Fe^0 under different conditions. Methods Nanoscale Fe^0 was synthesized by using reductive method. 4-CP and its intermediate products were analyzed by HPLC. Chlorine ion was quantified with DX-100 ion chromatograph. Nano-iron particles were observed under a FEI Quanta 200 FEG environmental scanning electron microscope (ESEM). Results The size of the particles was in the range of 10-100 nm. The nano-iron particles could reduce 4-CP effectively. The initial concentration of 4-CP increased with the decrease of the relative degradation rate, whereas the reduced amount of 4-CP increased. Temperature could influence both the dechlorination rate and the reaction pathway. Moreover, the stability and durability of nanoscale Fe^0 was evaluated through batch studies over extended periods of time. Conclusion The nanoscale Fe^0 can be used for sustainable treatment of contaminants in groundwater.
基金This work was supported by the National Science Foundation of China (Grant No. 40102027 50325824 50578151 and BeijingNatural Science Foundation 8052017).
文摘Objective To investigate the biodegradation of tetrachloroethylene (PCE) by acclimated anaerobic sludge using different co-substrates, i.e., glucose, acetate, and lactate as electron donors. Methods HP-6890 gas chromatograph (GC) in combination with auto-sampler was used to analyze the concentration of PCE and its intermediates, Results PCE could be degraded by reductive dechlorlnation and the degradation reaction conformed to the first-order kinetic equation. The rate constants are klaetate〉kglucose〉kacetate. The PCE degradation rate was the highest in the presence of lactate as an electron donor. Conclusion Lactate is the most suitable electron donor for PCE degradation and the electron donors supplied by co-metabolic substrates are not the limiting factors for PCE degradation,
基金supported by the National Natural Science Foundation of China (Grant No. 11772149)the Research Fund of State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics,China (Grant No. MCMS-I-19G01)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD),China。
文摘The generalized cell mapping(GCM) method is used to obtain the stationary response of a single-degree-of-freedom.Vibro-impact system under a colored noise excitation. In order to show the advantage of the GCM method, the stochastic averaging method is also presented. Both of the two methods are tested through concrete examples and verified by the direct numerical simulation. It is shown that the GCM method can well predict the stationary response of this noise-perturbed system no matter whether the noise is wide-band or narrow-band, while the stochastic averaging method is valid only for the wide-band noise.
基金This work was supported from the National Natural Science Foundation of China (No. 40102027 50578151) +1 种基金the Natural Science Foundation of Beijing (No. 8052017)The School-enterprise cooperation project of Beijing Municipal Education Commission (No.5190065005)
文摘Objective To investigate the biodegradation of tetrachloroethylene (PCE) using methanol as electron donor by acclimated anaerobic sludge. Methods HP-6890 gas chromatograph (GC), together with HP-7694 autosarnpler, was used to analyze the concentration of PCE and intermediates. Results PCE could be decholrinated reductively to DCE via TCE, and probably further to VC and ethylene. The degradation of PCE and TCE conformed to first-order reaction kinetics. The reaction rate constants were 0.8991 d^-1 and 0.068 d^-1, respectively, and the corresponding half-life were 0.77 d and 10.19 d, respectively. TCE production rate constant was 0.1333 d^-1, showing that PCE was degraded more rapidly than TCE. Conclusion Methanol is an electron donor suitable for PCE degradation and the cometabolic electron donors are not limiting factors for PCE degradation.
文摘Background: The European Society of Urogenital Radiology has built the Prostate Imaging Reporting and Data System (PI-RADS) for standardizing the diagnosis of prostate cancer (PCa). This study evaluated the PI-RADS diagnosis method in patients with prostate-specific antigen (PSA) 〈20 ng/ml. Methods: A total of 133 patients with PSA 〈20 ng/ml were prospectively recruited. T2-weighted (T2WI) and diffusion-weighted (DWI) magnetic resonance images of the prostate were acquired before a 12-core transrectal prostate biopsy. Each patient's peripheral zone was divided into six regions on the images; each region corresponded to two of the 12 biopsy cores. T2WI, DWI, and T2W1 + DWI scores were computed according to PI-RADS. The diagnostic accuracy of the PI-RADS score was evaluated using histopathology of prostate biopsies as the reference standard. Results: PCa was histologically diagnosed in 169 (21.2%) regions. Increased PI-RADS score correlated positively with increased cancer detection rate. The cancer detection rate for scores 1 to 5 was 2.8%, 15.0%, 34.6%, 52.6%, and 88.9%, respectively, using T2W1 and 12.0%, 20.2%, 48.0%, 85.7%, and 93.3%, respectively, using DWI. For T2WI + DWI, the cancer detection rate was 1.5% (score 2), 13.5% (scores 3-4), 41.3% (scores 5-6), 75.9% (scores 7-8), and 92.3% (scores 9-10). The area under the curve for cancer detection was 0.700 (T2WI), 0.735 (DWI) and 0.749 (T2WI + DWI). The sensitivity and specificity were 53.8% and 89.2%, respectively, when The summed score ofT2Wl + DWI
文摘Background: High rate of in-stent restenosis (ISR) remained an unsolved clinical problem in clinical practice, especially among patients with diabetes mellitus (DM). Diabetic patients often had hypertriglyceridemia with elevated levels of very low-density lipoprotein cholesterol (VLDL-C). Increasing evidence suggested that VLDL-C was known as a significant risk factor for atherosclerosis and had been recommended as a treatment target by current dyslipidemia guidelines. However, the role of VLDL-C in the occurrence and development of ISR in coronary artery disease (CAD) patients with DM had not been studied. The aim of this study was to evaluate the association between the elevated levels of VLDL-C and the risk of ISR in CAD patients with DM. Methods: A total of 1390 diabetic patients, who underwent coronary drug-eluting stent (DES) implantation at Beijing Anzhen Hospital and followed up by angiography within 6–24 months, were consecutively enrolled. Patients' demographic and clinical characteristics, including age, gender, CAD risk factors, family history, life style, medical history, and coronary angiographic information, were collected carefully at baseline percutaneous coronary intervention and follow-up angiography. Multivariate Cox&#39;s proportional hazards regression modeling using the step-wise method (entry, 0.05; removal, 0.05) was used to determine the independent risk associated with ISR in diabetic patients. Results: Finally, 1206 of patients were included in this study. ISR occurred in 132/1206 diabetic patients (10.9%) by follow-up angiography. Patients with ISR had elevated median serum VLDL-C levels compared with those without ISR (0.65 mmol/L vs. 0.52 mmol/L, P = 0.030). The multivariate regression analysis showed that VLDL-C was significantly associated with the risk of ISR in diabetic CAD patients (hazard ratio [HR] = 1.15, 95% confidence interval [CI]: 1.03–1.29, P = 0.017). The HR for the risk of ISR associated with VLDL-C level ≥0.52 mmol/L was 3.01 (95% CI: 1.24–7.34, P = 0.015). Conclusion: The elevated level of serum VLDL-C was a significant and independent risk factor for ISR in diabetic CAD patients after coronary DES implantation.