传统硅基太阳能电池的成本居高不下,溶液法制备的大面积、低成本电池是太阳能电池研究和发展的重要方向。喷墨打印制备工艺操作简单、靶向性强、材料利用率高,可大面积沉积钙钛矿薄膜,并且本文使用无毒试剂(水)做溶剂添加表面活性剂调...传统硅基太阳能电池的成本居高不下,溶液法制备的大面积、低成本电池是太阳能电池研究和发展的重要方向。喷墨打印制备工艺操作简单、靶向性强、材料利用率高,可大面积沉积钙钛矿薄膜,并且本文使用无毒试剂(水)做溶剂添加表面活性剂调节溶液表面张力,代替先前的有毒试剂,不会腐蚀喷墨打印头,是一种绿色打印技术,在标准光照下(AM1.5,100 m W cm-2)获得了13.2%的光电转化效率。展开更多
The pretreatment of refractory polyvinyl-alcohol (PVA) wastewater with low value of CODcr by Fenton's reagent was investigated to enhance the biodegradabilily. The effects of operating conditions such as pH of the ...The pretreatment of refractory polyvinyl-alcohol (PVA) wastewater with low value of CODcr by Fenton's reagent was investigated to enhance the biodegradabilily. The effects of operating conditions such as pH of the solution, Fe2+ dosage, H2O2 dosage, reaction time and initial PVA concentration on the removal efficiency of CODCr were discussed. It is demonstrated that the optimum value of pH for removal of CODcr is 5 and the most suitable dosages of H2O2 (2%) and FeSO4 (10 mg/L) are 5% and 8.0%, respectively. When the initial CODcr value of the PVA water is 760 mg/L, the favorable reaction time is 110 min. Under these optimum conditions, the removal ratio of CODcr is 58.6% 61.4%, and the value of biodegradability (CODB/CODcr) increases markedly from 8.9% 9.7% to 62.6% 68.3%.展开更多
AIM:To investigate the relationship between plasma acylated ghrelin levels and the pathophysiology of functional dyspepsia.METHODS:Twenty-two female patients with functional dyspepsia and twelve healthy volunteers wer...AIM:To investigate the relationship between plasma acylated ghrelin levels and the pathophysiology of functional dyspepsia.METHODS:Twenty-two female patients with functional dyspepsia and twelve healthy volunteers were recruited for the study.The functional dyspepsia patients were each diagnosed based on the Rome Ⅲ criteria.Eligible patients completed a questionnaire concerning the severity of 10 symptoms.Plasma acylated ghrelin levels before and after a meal were determined in the study participants using a commercial human acylated enzyme immunoassay kit;electrogastrograms were performed for 50 min before and after a standardized 10-min meal containing 265 kcal.RESULTS:There were no significant differences in plasma acylated ghrelin levels between healthy volunteers and patients with functional dyspepsia.However,in patients with functional dyspepsia,there was a negative correlation between fasting plasma acylated ghrelin levels and the sum score of epigastric pain(r =-0.427,P = 0.047) and a positive correlation between the postprandial/fasting plasma acylated ghrelin ratio and the sum score of early satiety(r = 0.428,P =0.047).Additionally,there was a negative correlation between fasting acylated ghrelin plasma levels and fasting normogastria(%)(r =-0.522,P = 0.013).Interestingly,two functional dyspepsia patients showed paradoxically elevated plasma acylated ghrelin levels after the meal.CONCLUSION:Abnormal plasma acylated ghrelin levels before or after a meal may be related to several of the dyspeptic symptoms seen in patients with functional dyspepsia.展开更多
In this research, centrifugal pump unit was analysed to study the effects of using inducers on its performance. Hydraulic tests were done to obtain the optimum hydraulic performance before and after using inducer. Two...In this research, centrifugal pump unit was analysed to study the effects of using inducers on its performance. Hydraulic tests were done to obtain the optimum hydraulic performance before and after using inducer. Two types of inducers were used in this work (axial, helical). For this purpose, a test rig was specially designed with a pump system to investigate the parameters under consideration. Plots (H-Q) curves, (B.P.-Q) curves and (q-Q) curves were used to show the effect of pump performance with and without inducers. The present study introduces a simulation of centrifugal pump performance in conjunction with inducers using CFD (Computational Fluid Dynamics), to compare it with experimentally observed values. The model investigates the impact of using inducers on the head and flow of the pump. The results of the CFD model and experimental are correlated well. Furthermore, the results help the decision makers of the pumps for future developments in pump performance assuring safe and reliable running condition of the water pumps. Also it may be used for more applications of larger head and flow pumps.展开更多
4-Chlorophenol (4-CP) solution was treated by dual-frequency ultrasound inconjunction with Fenton reagent, and obvious improvement in the 4-CP degradation rate was observedin this advanced oxidation process. Experimen...4-Chlorophenol (4-CP) solution was treated by dual-frequency ultrasound inconjunction with Fenton reagent, and obvious improvement in the 4-CP degradation rate was observedin this advanced oxidation process. Experimental results showed that ultrasonic intensity,saturating gas and pH value affected greatly the 4-CP removal rate. Among four different saturatinggases (Ar, O_2, air and N_2), 4-CP degradation with Ar-saturated solution was the best. However, inthe view of practical wastewater treatment, using oxygen as the saturating gas would be moreeconomical. The addition of Fenton reagent followed the first-order kinetics and increased the 4-CPdegradation rate. The 4-CP removal rate increased by around 126% within 15 min treatment. Thesynergetic effect of dual-frequency ultrasound with Fenton reagent on 4-CP degradation was obviouslyobserved.展开更多
To investigate the application of compound bioflocculant (CBF) in drinking water treatment at pilot plant, CBF and polymerized aluminium ferrum chloride (PAFC) coagulant were used to treat raw water taken from Lon...To investigate the application of compound bioflocculant (CBF) in drinking water treatment at pilot plant, CBF and polymerized aluminium ferrum chloride (PAFC) coagulant were used to treat raw water taken from Longhupao Reservoir in Heilongjiang Province for the removal of turbidity, COl), UV254 and residual Al. Coagulation test shows that the coagulation enhanced by CBF and PAFC exhibits more effective performance than that enhanced by the individual of them, and the total combination dosage is lower than that of the individual. The residual Al from PAFC can be removed efficiently by CBF. The removal efficiency of turbidity reaches 76.6% by combining CBF of 2 mg/L and PAFC of 15 mg/L, COl) is decreased from 3.80 mg/L to 1.62 mg/ L, and the concentration of residual Al is only 0. 033 mg/L in the product water. It can be speculated that adsorption-bridging and sweep-coagulation processes are predominant in the flocculation process by the combination of CBF and PAFC.展开更多
The effectiveness of an injection-based remediation strategy is primarily governed by accurate understanding of reagent delivery and ensuring uniform distribution within the reactive zone. In IRZ (in situ reactive z...The effectiveness of an injection-based remediation strategy is primarily governed by accurate understanding of reagent delivery and ensuring uniform distribution within the reactive zone. In IRZ (in situ reactive zone) design, the required reagent strength, injection volumes, injection rates, injection frequency, injection and monitoring well spacing, and the cost and time to achieve remediation goals are governed by the hydrogeology of the site. A properly designed tracer test is capable of providing critical above mentioned site-specific information, to assist with full scale design of an IRZ. This paper describes that implementing tracer testing to support remedial design can result in enhanced design efficiency, added assurance in full-scale implementation and ultimately resulted in substantial cost savings. Therefore, it is recommended that the broader practitioner community adopt this technique as a best practice for effective and optimum in situ remediation system design.展开更多
Nine kinds of reactive dye solutions: Reactive K -2RL, H-E2R, X-6B1Y, HE-4G, X-3B, K-2R, H - E7B, X -4RN and S - F3B were treated by using Fenton reagent. While the concentration of dye is 400 mg/L, the FeSO4 dosage 1...Nine kinds of reactive dye solutions: Reactive K -2RL, H-E2R, X-6B1Y, HE-4G, X-3B, K-2R, H - E7B, X -4RN and S - F3B were treated by using Fenton reagent. While the concentration of dye is 400 mg/L, the FeSO4 dosage 100 -180 mg/L, H2O2 240 -540 mg/L, that is the stoichiometric numbers of Fe2+ and H2O2 are between 1: 9 - 1:12, pH = 3, reaction tune In, temperature 25℃, the colority removal efficiency reach more than 95%, the COD removal efficiency 65% -85%, and the TOC removal efficiency 70.2%. By comparing UV-VIS absorption spectrum before and after treatment, it further shows that decomposition effect of Fenton reagent on these nine kinds of reactive dyes is satisfactory.展开更多
The present paper reports the testing of 14 OPC-slag mortars and 2 controls OPC and slag mortars. The main aim is to determine the optimum level of replacement slag for achievement to the highest early strength with r...The present paper reports the testing of 14 OPC-slag mortars and 2 controls OPC and slag mortars. The main aim is to determine the optimum level of replacement slag for achievement to the highest early strength with reasonable flow. Variable was the level of GGBFS in the binder. In this experimental work, two types of sands were used that are: silica and mining sands. It is determined that the optimum level of replacement slag is 40% and use of silica sand in OPC is preferable to mining sand and reversely, use of mining sand is preferred in GG100 to silica sand. All mortars had W/B and S/B 0.33 and 2.25, respectively.展开更多
Dynamic model for dehydration process of industrial purified terephthalic acid solvent is investigated to understand and characterize the process.A temperature differential expression is presented,which ensures the eq...Dynamic model for dehydration process of industrial purified terephthalic acid solvent is investigated to understand and characterize the process.A temperature differential expression is presented,which ensures the equation to convergence and short computation time.The model is used to study the dynamic behavior of an azeotropic distillation column separating acetic acid and water using n-butyl acetate as the entrainer.Responses of the column to feed flow and aqueous reflux flow are simulated.The movement of temperature front is also simulated.The comparison between simulation and industrial values shows that the model and algorithm are effective.On the basis of simulation and analysis,control strategy,online optimization and so on can be implemented effectively in dehydration process of purified terephthalic acid solvent.展开更多
文摘传统硅基太阳能电池的成本居高不下,溶液法制备的大面积、低成本电池是太阳能电池研究和发展的重要方向。喷墨打印制备工艺操作简单、靶向性强、材料利用率高,可大面积沉积钙钛矿薄膜,并且本文使用无毒试剂(水)做溶剂添加表面活性剂调节溶液表面张力,代替先前的有毒试剂,不会腐蚀喷墨打印头,是一种绿色打印技术,在标准光照下(AM1.5,100 m W cm-2)获得了13.2%的光电转化效率。
基金Project(08JCYBJC02600) supported by the Natural Science Foundation of Tianjin,ChinaProject(2008ZX07314-005-011) supported by the National Major Technological Program of China
文摘The pretreatment of refractory polyvinyl-alcohol (PVA) wastewater with low value of CODcr by Fenton's reagent was investigated to enhance the biodegradabilily. The effects of operating conditions such as pH of the solution, Fe2+ dosage, H2O2 dosage, reaction time and initial PVA concentration on the removal efficiency of CODCr were discussed. It is demonstrated that the optimum value of pH for removal of CODcr is 5 and the most suitable dosages of H2O2 (2%) and FeSO4 (10 mg/L) are 5% and 8.0%, respectively. When the initial CODcr value of the PVA water is 760 mg/L, the favorable reaction time is 110 min. Under these optimum conditions, the removal ratio of CODcr is 58.6% 61.4%, and the value of biodegradability (CODB/CODcr) increases markedly from 8.9% 9.7% to 62.6% 68.3%.
文摘AIM:To investigate the relationship between plasma acylated ghrelin levels and the pathophysiology of functional dyspepsia.METHODS:Twenty-two female patients with functional dyspepsia and twelve healthy volunteers were recruited for the study.The functional dyspepsia patients were each diagnosed based on the Rome Ⅲ criteria.Eligible patients completed a questionnaire concerning the severity of 10 symptoms.Plasma acylated ghrelin levels before and after a meal were determined in the study participants using a commercial human acylated enzyme immunoassay kit;electrogastrograms were performed for 50 min before and after a standardized 10-min meal containing 265 kcal.RESULTS:There were no significant differences in plasma acylated ghrelin levels between healthy volunteers and patients with functional dyspepsia.However,in patients with functional dyspepsia,there was a negative correlation between fasting plasma acylated ghrelin levels and the sum score of epigastric pain(r =-0.427,P = 0.047) and a positive correlation between the postprandial/fasting plasma acylated ghrelin ratio and the sum score of early satiety(r = 0.428,P =0.047).Additionally,there was a negative correlation between fasting acylated ghrelin plasma levels and fasting normogastria(%)(r =-0.522,P = 0.013).Interestingly,two functional dyspepsia patients showed paradoxically elevated plasma acylated ghrelin levels after the meal.CONCLUSION:Abnormal plasma acylated ghrelin levels before or after a meal may be related to several of the dyspeptic symptoms seen in patients with functional dyspepsia.
文摘In this research, centrifugal pump unit was analysed to study the effects of using inducers on its performance. Hydraulic tests were done to obtain the optimum hydraulic performance before and after using inducer. Two types of inducers were used in this work (axial, helical). For this purpose, a test rig was specially designed with a pump system to investigate the parameters under consideration. Plots (H-Q) curves, (B.P.-Q) curves and (q-Q) curves were used to show the effect of pump performance with and without inducers. The present study introduces a simulation of centrifugal pump performance in conjunction with inducers using CFD (Computational Fluid Dynamics), to compare it with experimentally observed values. The model investigates the impact of using inducers on the head and flow of the pump. The results of the CFD model and experimental are correlated well. Furthermore, the results help the decision makers of the pumps for future developments in pump performance assuring safe and reliable running condition of the water pumps. Also it may be used for more applications of larger head and flow pumps.
基金Partly supported by the National Natural Science Foundation of China (No. 20176053)Academic Foundation of Zhejiang University of Technology (No. 20040004).
文摘4-Chlorophenol (4-CP) solution was treated by dual-frequency ultrasound inconjunction with Fenton reagent, and obvious improvement in the 4-CP degradation rate was observedin this advanced oxidation process. Experimental results showed that ultrasonic intensity,saturating gas and pH value affected greatly the 4-CP removal rate. Among four different saturatinggases (Ar, O_2, air and N_2), 4-CP degradation with Ar-saturated solution was the best. However, inthe view of practical wastewater treatment, using oxygen as the saturating gas would be moreeconomical. The addition of Fenton reagent followed the first-order kinetics and increased the 4-CPdegradation rate. The 4-CP removal rate increased by around 126% within 15 min treatment. Thesynergetic effect of dual-frequency ultrasound with Fenton reagent on 4-CP degradation was obviouslyobserved.
文摘To investigate the application of compound bioflocculant (CBF) in drinking water treatment at pilot plant, CBF and polymerized aluminium ferrum chloride (PAFC) coagulant were used to treat raw water taken from Longhupao Reservoir in Heilongjiang Province for the removal of turbidity, COl), UV254 and residual Al. Coagulation test shows that the coagulation enhanced by CBF and PAFC exhibits more effective performance than that enhanced by the individual of them, and the total combination dosage is lower than that of the individual. The residual Al from PAFC can be removed efficiently by CBF. The removal efficiency of turbidity reaches 76.6% by combining CBF of 2 mg/L and PAFC of 15 mg/L, COl) is decreased from 3.80 mg/L to 1.62 mg/ L, and the concentration of residual Al is only 0. 033 mg/L in the product water. It can be speculated that adsorption-bridging and sweep-coagulation processes are predominant in the flocculation process by the combination of CBF and PAFC.
文摘The effectiveness of an injection-based remediation strategy is primarily governed by accurate understanding of reagent delivery and ensuring uniform distribution within the reactive zone. In IRZ (in situ reactive zone) design, the required reagent strength, injection volumes, injection rates, injection frequency, injection and monitoring well spacing, and the cost and time to achieve remediation goals are governed by the hydrogeology of the site. A properly designed tracer test is capable of providing critical above mentioned site-specific information, to assist with full scale design of an IRZ. This paper describes that implementing tracer testing to support remedial design can result in enhanced design efficiency, added assurance in full-scale implementation and ultimately resulted in substantial cost savings. Therefore, it is recommended that the broader practitioner community adopt this technique as a best practice for effective and optimum in situ remediation system design.
文摘Nine kinds of reactive dye solutions: Reactive K -2RL, H-E2R, X-6B1Y, HE-4G, X-3B, K-2R, H - E7B, X -4RN and S - F3B were treated by using Fenton reagent. While the concentration of dye is 400 mg/L, the FeSO4 dosage 100 -180 mg/L, H2O2 240 -540 mg/L, that is the stoichiometric numbers of Fe2+ and H2O2 are between 1: 9 - 1:12, pH = 3, reaction tune In, temperature 25℃, the colority removal efficiency reach more than 95%, the COD removal efficiency 65% -85%, and the TOC removal efficiency 70.2%. By comparing UV-VIS absorption spectrum before and after treatment, it further shows that decomposition effect of Fenton reagent on these nine kinds of reactive dyes is satisfactory.
文摘The present paper reports the testing of 14 OPC-slag mortars and 2 controls OPC and slag mortars. The main aim is to determine the optimum level of replacement slag for achievement to the highest early strength with reasonable flow. Variable was the level of GGBFS in the binder. In this experimental work, two types of sands were used that are: silica and mining sands. It is determined that the optimum level of replacement slag is 40% and use of silica sand in OPC is preferable to mining sand and reversely, use of mining sand is preferred in GG100 to silica sand. All mortars had W/B and S/B 0.33 and 2.25, respectively.
基金Supported by the National Natural Science Foundation of China(61072127) the Outstanding Young Innovative Personnel Project of Guangdong Colleges(LYM08098)
文摘Dynamic model for dehydration process of industrial purified terephthalic acid solvent is investigated to understand and characterize the process.A temperature differential expression is presented,which ensures the equation to convergence and short computation time.The model is used to study the dynamic behavior of an azeotropic distillation column separating acetic acid and water using n-butyl acetate as the entrainer.Responses of the column to feed flow and aqueous reflux flow are simulated.The movement of temperature front is also simulated.The comparison between simulation and industrial values shows that the model and algorithm are effective.On the basis of simulation and analysis,control strategy,online optimization and so on can be implemented effectively in dehydration process of purified terephthalic acid solvent.