Microstructured targets demonstrate an enhanced coupling of high-intensity laser pulse to a target and play an important role in laser-induced ion acceleration.Here we demonstrate an approach that enables us to contro...Microstructured targets demonstrate an enhanced coupling of high-intensity laser pulse to a target and play an important role in laser-induced ion acceleration.Here we demonstrate an approach that enables us to control the morphology of amorphous solid water(ASW)microstructured targets,by deposition of water vapor on a charged substrate,cooled down to 100 K.The morphology of the deposited ASW structures is controlled by varying the surface charge on the substrate and the pressure of water vapor.The obtained target is structured as multiple,dense spikes,confined by the charged area on the substrate,with increased aspect ratio of up to 5:1 and having a diameter comparable with the typical spot size of the laser focused onto the target.展开更多
To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry ...To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.展开更多
A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile ...A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD.展开更多
The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial utilization.In this study,a combined hydrolytic-aerobic biodrying technology ...The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial utilization.In this study,a combined hydrolytic-aerobic biodrying technology was introduced to remove water from MSW.The total water removals were proved to depend on the ventilation frequency and the temporal span in the hydrolytic stage. The ventilation frequency of 6 times/d was preferable in the hydrolytic stage.The hydrolytic span should not be prolonged more than ...展开更多
Water samples from four water bodies that flow through some solid waste dump sites in the Accra metropolitan area of Ghana were analysed over a period of six months for Cd, Pb, Cu, Zn and Mn contents;coliform bacteria...Water samples from four water bodies that flow through some solid waste dump sites in the Accra metropolitan area of Ghana were analysed over a period of six months for Cd, Pb, Cu, Zn and Mn contents;coliform bacteria and helminth eggs. Other water quality parameters such as BOD, DO, suspended solids and turbidity were also assessed. Cd, Pb, Zn, Mn, and Cu were determined using flame atomic absorption spectrometry (FAAS). Faecal coliforms, total coliforms and helminth eggs were determined by the membrane filtration (MF) method. The water samples contain various levels of Cd, Pb and Mn;Zn and Cu levels were low and found to be below the detection levels of the instrument in most cases. Helminth egg counts in water samples were high;an indication that the water bodies were polluted with pathogens. It has been observed that the major sources of pollutants into the water bodies were organic waste as well as coliform bacteria derived from these waste dumps. The elevated levels of bacteria make the water bodies unsafe for both primary and secondary contacts.展开更多
The increasing application of near balanced drilling technology to low-pressure and depleted fractured reservoirs requires the use of low-density drilling fluids to avoid formation damage. Solidsfree oil-in-water (O/...The increasing application of near balanced drilling technology to low-pressure and depleted fractured reservoirs requires the use of low-density drilling fluids to avoid formation damage. Solidsfree oil-in-water (O/W) emulsion drilling fluid is one type of low-density drilling fluid suitable for depleted fractured reservoirs. In this paper, the solids-free O/W drilling fluid was developed and has been successfully used in the Bozhong 28-1 oil and gas field, by which lost circulation, a severe problem occurred previously when drilling into fractured reservoir beds, was controlled, thereby minimizing formation damage. The O/W emulsion drilling fluid was prepared by adding 20% (by volume) No. 5 mineral oil (with high flash point, as dispersed phase) into seawater (as continuous phase). Surfactant HTO-1 (as a primary emulsifier) and non-ionic surfactant HTO-2 (as a secondary emulsifier) were added into the drilling fluid system to stabilize the emulsion; and YJD polymer was also added to seawater to improve the viscosity of the continuous phase (seawater). The drilling fluid was characterized by high flash point, good thermal stability and high stability to crude oil contamination.展开更多
A solid ternary mixture consisting of NaF, silicon and one of the metal oxides such as Al2O3, MgO, CaO, SrO, BaO was prepared and used as a defluorinated reagent for CF4 decomposition. The results show that the initia...A solid ternary mixture consisting of NaF, silicon and one of the metal oxides such as Al2O3, MgO, CaO, SrO, BaO was prepared and used as a defluorinated reagent for CF4 decomposition. The results show that the initial conversion of CF4 reached 100% over NaF-Si-MgO and NaF-Si-CaO at 850°C, and the reagent with NaF/Si/MgO molar ratio of 33/34/33 exhibited a high reactivity with a full conversion of CF4 lasting for 57 min. The plausible paths of CF4 decomposition over NaF-Si-Al2O3, NaF-Si-MgO, NaF-Si-CaO, NaF-Si-SrO and NaF-Si-BaO are proposed.展开更多
Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorptio...Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate(ZS) loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20% (mass fraction) ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.展开更多
Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, th...Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, the free water, surface water and capillary water are in turn vaporized at different rates, then the turning points of the rates are determined and the quantitative analysis can be made. Some experiments with suspension of water and CaCO 3 powder were given and discussed by applying the vaporization dewatering approach. [展开更多
Accumulating operational experience in both aerobic and anaerobic mechanical biological waste treatment (MBT) makes it increasingly obvious that controlled water management would substantially reduce the cost of MBT...Accumulating operational experience in both aerobic and anaerobic mechanical biological waste treatment (MBT) makes it increasingly obvious that controlled water management would substantially reduce the cost of MBT and also enhance resource recovery of the organic and inorganic fraction. The MBT plant at Gescher, Germany, is used as an example in order to determine the quantity and composition of process water and leachates from intensive and subsequent rotting, pressing water from anaerobic digestion and scrubber water from acid exhaust air treatment, and hence prepare an MBT water balance. The potential of, requirements for and limits to internal process water reuse as well as the possibilities of resource recovery from scrubber water are also examined. Finally, an assimilated process water management concept with the purpose of an extensive reduction of wastewater quantity and freshwater demand is presented.展开更多
Silicate perovskites((Mg, Fe)SiO 3 and CaS iO 3) are believed to be the major constituent minerals in the lower mantle. The phase relation, solid solution, spin state of iron and water solubility related to the lo...Silicate perovskites((Mg, Fe)SiO 3 and CaS iO 3) are believed to be the major constituent minerals in the lower mantle. The phase relation, solid solution, spin state of iron and water solubility related to the lower mantle perovskite are of great effect on the geodynamics of the Earth's interior and on ore mineralization. Previous studies indicate that a large amount of iron coupled with aluminum can incorporate into magnesium perovskite, but this is discordant with the disproportionation of(Mg,Fe)SiO 3 perovskite into iron-free MgS i O3 perovskite and hexagonal phase(Mg0.6Fe0.4)SiO 3 in the Earth's lower mantle. MnS iO 3 is the first chemical component confirmed to form wide range solid solution with Ca SiO 3 perovskite and complete solid solution with MgS i O3 perovskite at the P-T conditions in the lower mantle, and addition of Mn Si O3 will strongly affects the mutual solubility between Mg Si O3 and CaS iO 3. The spin state of iron is deeply depends on the site occupation of the Fe3+or Fe2+, the synthesis and the annealing conditions of the sample. It seems that the spin state of Fe2+ in the lower mantle perovskite can be settled as high spin, however, the existence of intermediate spin or low spin state of Fe2+ in perovskite has not been clarified. Moreover, different results have also been reported for the spin state of Fe3+ in perovskite. The water solubility of the lower mantle perovskite is related with its composition. In pure Mg SiO 3 perovskite, only less than 500 ppm water was reported. Al–Mg Si O3 perovskite or Al–Fe–MgS iO 3 perovskite in the lower mantle accommodates water of 1100 to 1800 ppm. Further experiments are necessary to clarify the detailed conditions for perovskite solid solution, to reliably analyze the valence and spin states of iron in the coexisting iron-bearing phases, and to compare the water solubility of different phases at different layers for deeply understanding the geodynamics of the Earth's interior and ore mineralization.展开更多
Headspace solid-phase microextraction(HS-SPME) with sol-gel calix[6]arene-containing fiber followed by gas chromatography with a flame ionization detector was used to examine the composition and distribution of seve...Headspace solid-phase microextraction(HS-SPME) with sol-gel calix[6]arene-containing fiber followed by gas chromatography with a flame ionization detector was used to examine the composition and distribution of seven polycyclic aromatic hydrocarbons(PAHs) in water. The novel SPME fiber exhibited higher extraction efficiency to PAHs compared with poly(dimethylsiloxane) and other calixarene-containing fibers. Extraction/retention mechanism based on the interactions between calixarenes and PAHs was discussed. Owing to the good selectivity and high extraction capability of this calixarene fiber, low detection limits were obtained in a range of 0.34―6.50 ng/L and the relative standard deviation values were ≤12.3% for all of the analytes. The linear ranges of the proposed method were five orders of magnitude for the tested compounds, with linear correlation coefficients(r) greater than 0.998. The method was applied to the determination of polycyclic aromatic hydrocarbons in nine water sources in Wuhan City, China. Standard addition method was selected for the quantification and the recovery values were in a satisfactory range. Total PAHs concentrations in the nine surface water samples were found to vary between undetectable and 8.840 μg/L with two- and three-ring PAHs predominating.展开更多
[Objective] To develop a solid phase extraction-high performance liquid chromatography-fluorescence method for determination of quin- olone antibiotics in water. [ Metbod] The standard curves of four quinolones (norf...[Objective] To develop a solid phase extraction-high performance liquid chromatography-fluorescence method for determination of quin- olone antibiotics in water. [ Metbod] The standard curves of four quinolones (norfloxacin, ciprofloxacin, Iomefloxacin and enrofloxacin) were pre- pared. The detection limit in water and recovery were determined. The water samples collected from different areas, river and tap water were trea- ted using solid-phese extraction method and analyzed by high performance liquid chromatography. Then the concentration of quinolones antibiotics was determined by fluorescence method. [ Result] The detection limit of quinolone antibiotics in water was 0.083 -0.248 μg/L, and their recovery was 63.7% -134.1%. The four quinolone antibiotics at different levels were detected in various water samples, and the total concentration of quin- olone antibiotics was 0.045 -3.969 μg/L. The total concentration of quinolone antibiotics was higher in the water samples collected from rivers in Shenzhen area than in the sewage samples. The four quinolone antibiotics could be detected in all tap water samples. [ CoaduLsion ] The solid phase extraction-high performance liquid chromatography-fluorescence method is feasible and effective to detect quinolones in water. In addition, this method needs low cost and can meet requirements of daily monitorina and analysis.展开更多
Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasi...Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasing across the globe. In this study, the physical parameters of potable well waters in the key mining areas in Nimikoro and Tankoro Chiefdoms in Kono District were analyzed for compliance with drinking water quality standard. To do this, both unpurged and purged well water samples were collected once every month for a period of one year. Some of the well water properties like temperature, Total Dissolved Solids (TDS) and Electrical Conductivity (EC) were measured on site and others determined in the laboratory. The data collected from the laboratory analyses were statistically analyzed in MS Excel, SPSS and ArcGIS environments for quality trends in time-space fabric. The results showed that well water quality in the study area generally fell short of drinking water quality standards of Sierra Leone and WHO. There were high temperature and turbidity during the dry season and then high TDS and EC during the rainy season. Temperature and turbidity also significantly influenced well water quality in the study area, much more than TDS and EC. The implications for drinking water of lower quality than the standard could be huge for the local population and therefore needs the attention of stakeholders in the study area and decision makers in the country.展开更多
Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production w...Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production well, the produced fluids commonly contain water. The understanding of this water’s constituents and volumes is vital for the sustainable continuity of production operations, as PW has a number of negative impacts on the infrastructure integrity of the operation. On the other hand, PW can be an alternative source of irrigation water as well as of industrial salt. Interestingly, both the quantity as well as the quality of PW do not remain constant but can vary, both progressively and erratically, even over short periods of time. This paper discusses such a situation of variable PW in an oil and gas operation in the State of Kuwait.展开更多
This article describes MSW(Municipal Solid Waste)management with APG(Arc Plasma Gasification)technology.First,a brief description of the process and reactor configurations is presented,listing some advantages and disa...This article describes MSW(Municipal Solid Waste)management with APG(Arc Plasma Gasification)technology.First,a brief description of the process and reactor configurations is presented,listing some advantages and disadvantages.Then,alternatives for producing electrical energy with the residue of synthesis gas are addressed.Finally,this technology is proposed as an alternative to face the significant problem of eliminating MSW on a large scale.展开更多
Impulse turbine, working as a typical self-rectifying turbine, is recently utilized for the oscillating water column(OWC) wave energy converters, which can rotate in the same direction under the bi-directional air f...Impulse turbine, working as a typical self-rectifying turbine, is recently utilized for the oscillating water column(OWC) wave energy converters, which can rotate in the same direction under the bi-directional air flows. A numerical model established in Fluent is validated by the corresponding experimental results. The flow fields, pressure distribution and dimensionless evaluating coefficients can be calculated and analyzed. Effects of the rotor solidity varying with the change of blade number are investigated and the suitable solidity value is recommended for different flow coefficients.展开更多
The structure and dynamics of water in a thick film on an ionic surface are studied by molecular dynamic simulations. We find that there is a dense monolayer of water molecules in the vicinity of the surface. Water mo...The structure and dynamics of water in a thick film on an ionic surface are studied by molecular dynamic simulations. We find that there is a dense monolayer of water molecules in the vicinity of the surface. Water molecules within this layer not only show an upright hydrogen-down orientation, but also an upright hydrogen-up orientation. Thus, water molecules in this layer can form hydrogen bonds with water molecules in the next layer. Therefore, the two-dimensional hydrogen bond network of the first layer is disrupted, mainly due to the 0 atoms in this layer, which are affected by the next layer and are unstable. Moreover, these water molecules exhibit delayed dynamic behavior with relatively long residence time compared with those bulk-like molecules in the other layers. Our study should be halpful to further understand the influence of water film thickness on the interfacial water at the solid-liquid interface.展开更多
A small amount of mineralizer MgO was added into Al2TiO5 synthesized from the sludge of aluminum factory to form Al(2-x)Mg(x+y)Ti(1-y)O(5-0.5x-y) solid solution and inhibit the decomposition of Al2TiO5 solid ...A small amount of mineralizer MgO was added into Al2TiO5 synthesized from the sludge of aluminum factory to form Al(2-x)Mg(x+y)Ti(1-y)O(5-0.5x-y) solid solution and inhibit the decomposition of Al2TiO5 solid solution. It increased the content of Al2TiO5 solid solution and improved the thermal stability of materials. In this work,XRD and SEM methods were adopted to characterize the crystalline structure and microstructure of each kind of sample. Rietveld Quantification method was used to determine the content of crystalline phases in each sample. Results show as follows: the optimal addition concentration of MgO was 2.0%,and the corresponding content of Al2TiO5 solid solution which displayed irregular bulk shape was 100%; the addition of mineralizer MgO could enhance the flexural strength and thermal stability of Al2TiO5 solid solution materials. The optimal addition concentration of MgO determined by performance analysis was 2.0%,and its corresponding retention rate of thermal-shock flexural strength was 86.4%. Structure analysis and performance analysis resulted in good accordance.展开更多
文摘Microstructured targets demonstrate an enhanced coupling of high-intensity laser pulse to a target and play an important role in laser-induced ion acceleration.Here we demonstrate an approach that enables us to control the morphology of amorphous solid water(ASW)microstructured targets,by deposition of water vapor on a charged substrate,cooled down to 100 K.The morphology of the deposited ASW structures is controlled by varying the surface charge on the substrate and the pressure of water vapor.The obtained target is structured as multiple,dense spikes,confined by the charged area on the substrate,with increased aspect ratio of up to 5:1 and having a diameter comparable with the typical spot size of the laser focused onto the target.
基金supported by the Preventive medicine and public health research project of Anhui,China(No.2011Y0103)the Natural Science Foundation of Anhui,China(No.11040606M216)
文摘To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.
文摘A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD.
基金supported by the National Key Technolo-gy R&D Program(No.2006BAC06B04,2006BAC02A03)the Key Grant Project of Shanghai Committee of Science and Technology(No.06dz12308).
文摘The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial utilization.In this study,a combined hydrolytic-aerobic biodrying technology was introduced to remove water from MSW.The total water removals were proved to depend on the ventilation frequency and the temporal span in the hydrolytic stage. The ventilation frequency of 6 times/d was preferable in the hydrolytic stage.The hydrolytic span should not be prolonged more than ...
文摘Water samples from four water bodies that flow through some solid waste dump sites in the Accra metropolitan area of Ghana were analysed over a period of six months for Cd, Pb, Cu, Zn and Mn contents;coliform bacteria and helminth eggs. Other water quality parameters such as BOD, DO, suspended solids and turbidity were also assessed. Cd, Pb, Zn, Mn, and Cu were determined using flame atomic absorption spectrometry (FAAS). Faecal coliforms, total coliforms and helminth eggs were determined by the membrane filtration (MF) method. The water samples contain various levels of Cd, Pb and Mn;Zn and Cu levels were low and found to be below the detection levels of the instrument in most cases. Helminth egg counts in water samples were high;an indication that the water bodies were polluted with pathogens. It has been observed that the major sources of pollutants into the water bodies were organic waste as well as coliform bacteria derived from these waste dumps. The elevated levels of bacteria make the water bodies unsafe for both primary and secondary contacts.
文摘The increasing application of near balanced drilling technology to low-pressure and depleted fractured reservoirs requires the use of low-density drilling fluids to avoid formation damage. Solidsfree oil-in-water (O/W) emulsion drilling fluid is one type of low-density drilling fluid suitable for depleted fractured reservoirs. In this paper, the solids-free O/W drilling fluid was developed and has been successfully used in the Bozhong 28-1 oil and gas field, by which lost circulation, a severe problem occurred previously when drilling into fractured reservoir beds, was controlled, thereby minimizing formation damage. The O/W emulsion drilling fluid was prepared by adding 20% (by volume) No. 5 mineral oil (with high flash point, as dispersed phase) into seawater (as continuous phase). Surfactant HTO-1 (as a primary emulsifier) and non-ionic surfactant HTO-2 (as a secondary emulsifier) were added into the drilling fluid system to stabilize the emulsion; and YJD polymer was also added to seawater to improve the viscosity of the continuous phase (seawater). The drilling fluid was characterized by high flash point, good thermal stability and high stability to crude oil contamination.
基金financially supported by the National Natural Science Foundation of China(No.20976149)
文摘A solid ternary mixture consisting of NaF, silicon and one of the metal oxides such as Al2O3, MgO, CaO, SrO, BaO was prepared and used as a defluorinated reagent for CF4 decomposition. The results show that the initial conversion of CF4 reached 100% over NaF-Si-MgO and NaF-Si-CaO at 850°C, and the reagent with NaF/Si/MgO molar ratio of 33/34/33 exhibited a high reactivity with a full conversion of CF4 lasting for 57 min. The plausible paths of CF4 decomposition over NaF-Si-Al2O3, NaF-Si-MgO, NaF-Si-CaO, NaF-Si-SrO and NaF-Si-BaO are proposed.
基金Supported by the Research Fund for the Doctoral Program of Higher Education(No20050010014)the China Petroleum &Chemical Corporation ( No X503015 )the Key Discipline Construction Foundation of Beijing Education Committee ( NoXK100100643)
文摘Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate(ZS) loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20% (mass fraction) ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.
文摘Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, the free water, surface water and capillary water are in turn vaporized at different rates, then the turning points of the rates are determined and the quantitative analysis can be made. Some experiments with suspension of water and CaCO 3 powder were given and discussed by applying the vaporization dewatering approach. [
文摘Accumulating operational experience in both aerobic and anaerobic mechanical biological waste treatment (MBT) makes it increasingly obvious that controlled water management would substantially reduce the cost of MBT and also enhance resource recovery of the organic and inorganic fraction. The MBT plant at Gescher, Germany, is used as an example in order to determine the quantity and composition of process water and leachates from intensive and subsequent rotting, pressing water from anaerobic digestion and scrubber water from acid exhaust air treatment, and hence prepare an MBT water balance. The potential of, requirements for and limits to internal process water reuse as well as the possibilities of resource recovery from scrubber water are also examined. Finally, an assimilated process water management concept with the purpose of an extensive reduction of wastewater quantity and freshwater demand is presented.
基金partly supported by projects from JSPS KAKENHI (Grant No. 18340167)MEXT KAKENHI (Grant No. 20103002)+2 种基金NSFC (Grand No.90914002)China Geological Survey (Grant No. 1212011220926)the Ministry of Education of China (Grant No. 20130022110003)
文摘Silicate perovskites((Mg, Fe)SiO 3 and CaS iO 3) are believed to be the major constituent minerals in the lower mantle. The phase relation, solid solution, spin state of iron and water solubility related to the lower mantle perovskite are of great effect on the geodynamics of the Earth's interior and on ore mineralization. Previous studies indicate that a large amount of iron coupled with aluminum can incorporate into magnesium perovskite, but this is discordant with the disproportionation of(Mg,Fe)SiO 3 perovskite into iron-free MgS i O3 perovskite and hexagonal phase(Mg0.6Fe0.4)SiO 3 in the Earth's lower mantle. MnS iO 3 is the first chemical component confirmed to form wide range solid solution with Ca SiO 3 perovskite and complete solid solution with MgS i O3 perovskite at the P-T conditions in the lower mantle, and addition of Mn Si O3 will strongly affects the mutual solubility between Mg Si O3 and CaS iO 3. The spin state of iron is deeply depends on the site occupation of the Fe3+or Fe2+, the synthesis and the annealing conditions of the sample. It seems that the spin state of Fe2+ in the lower mantle perovskite can be settled as high spin, however, the existence of intermediate spin or low spin state of Fe2+ in perovskite has not been clarified. Moreover, different results have also been reported for the spin state of Fe3+ in perovskite. The water solubility of the lower mantle perovskite is related with its composition. In pure Mg SiO 3 perovskite, only less than 500 ppm water was reported. Al–Mg Si O3 perovskite or Al–Fe–MgS iO 3 perovskite in the lower mantle accommodates water of 1100 to 1800 ppm. Further experiments are necessary to clarify the detailed conditions for perovskite solid solution, to reliably analyze the valence and spin states of iron in the coexisting iron-bearing phases, and to compare the water solubility of different phases at different layers for deeply understanding the geodynamics of the Earth's interior and ore mineralization.
基金Supported by the National Natural Science Foundation of China(No.30901007)the Fund of the Ministry of Education of China(No.081025)
文摘Headspace solid-phase microextraction(HS-SPME) with sol-gel calix[6]arene-containing fiber followed by gas chromatography with a flame ionization detector was used to examine the composition and distribution of seven polycyclic aromatic hydrocarbons(PAHs) in water. The novel SPME fiber exhibited higher extraction efficiency to PAHs compared with poly(dimethylsiloxane) and other calixarene-containing fibers. Extraction/retention mechanism based on the interactions between calixarenes and PAHs was discussed. Owing to the good selectivity and high extraction capability of this calixarene fiber, low detection limits were obtained in a range of 0.34―6.50 ng/L and the relative standard deviation values were ≤12.3% for all of the analytes. The linear ranges of the proposed method were five orders of magnitude for the tested compounds, with linear correlation coefficients(r) greater than 0.998. The method was applied to the determination of polycyclic aromatic hydrocarbons in nine water sources in Wuhan City, China. Standard addition method was selected for the quantification and the recovery values were in a satisfactory range. Total PAHs concentrations in the nine surface water samples were found to vary between undetectable and 8.840 μg/L with two- and three-ring PAHs predominating.
基金funded by the grants from the China Natural Science Foundation ( 30671208 and 40773062)Key Project of Guangdong Natural Science Foundation ( 07117909)Science and Technology Planning Project of Guangdong Province( 2005B20801002 and 2006B20601003)
文摘[Objective] To develop a solid phase extraction-high performance liquid chromatography-fluorescence method for determination of quin- olone antibiotics in water. [ Metbod] The standard curves of four quinolones (norfloxacin, ciprofloxacin, Iomefloxacin and enrofloxacin) were pre- pared. The detection limit in water and recovery were determined. The water samples collected from different areas, river and tap water were trea- ted using solid-phese extraction method and analyzed by high performance liquid chromatography. Then the concentration of quinolones antibiotics was determined by fluorescence method. [ Result] The detection limit of quinolone antibiotics in water was 0.083 -0.248 μg/L, and their recovery was 63.7% -134.1%. The four quinolone antibiotics at different levels were detected in various water samples, and the total concentration of quin- olone antibiotics was 0.045 -3.969 μg/L. The total concentration of quinolone antibiotics was higher in the water samples collected from rivers in Shenzhen area than in the sewage samples. The four quinolone antibiotics could be detected in all tap water samples. [ CoaduLsion ] The solid phase extraction-high performance liquid chromatography-fluorescence method is feasible and effective to detect quinolones in water. In addition, this method needs low cost and can meet requirements of daily monitorina and analysis.
文摘Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasing across the globe. In this study, the physical parameters of potable well waters in the key mining areas in Nimikoro and Tankoro Chiefdoms in Kono District were analyzed for compliance with drinking water quality standard. To do this, both unpurged and purged well water samples were collected once every month for a period of one year. Some of the well water properties like temperature, Total Dissolved Solids (TDS) and Electrical Conductivity (EC) were measured on site and others determined in the laboratory. The data collected from the laboratory analyses were statistically analyzed in MS Excel, SPSS and ArcGIS environments for quality trends in time-space fabric. The results showed that well water quality in the study area generally fell short of drinking water quality standards of Sierra Leone and WHO. There were high temperature and turbidity during the dry season and then high TDS and EC during the rainy season. Temperature and turbidity also significantly influenced well water quality in the study area, much more than TDS and EC. The implications for drinking water of lower quality than the standard could be huge for the local population and therefore needs the attention of stakeholders in the study area and decision makers in the country.
文摘Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production well, the produced fluids commonly contain water. The understanding of this water’s constituents and volumes is vital for the sustainable continuity of production operations, as PW has a number of negative impacts on the infrastructure integrity of the operation. On the other hand, PW can be an alternative source of irrigation water as well as of industrial salt. Interestingly, both the quantity as well as the quality of PW do not remain constant but can vary, both progressively and erratically, even over short periods of time. This paper discusses such a situation of variable PW in an oil and gas operation in the State of Kuwait.
文摘This article describes MSW(Municipal Solid Waste)management with APG(Arc Plasma Gasification)technology.First,a brief description of the process and reactor configurations is presented,listing some advantages and disadvantages.Then,alternatives for producing electrical energy with the residue of synthesis gas are addressed.Finally,this technology is proposed as an alternative to face the significant problem of eliminating MSW on a large scale.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51279190 and 51311140259)the Shandong Province Natural Science Foundation for Distinguished Young Scholars(Grant No.JQ201314)
文摘Impulse turbine, working as a typical self-rectifying turbine, is recently utilized for the oscillating water column(OWC) wave energy converters, which can rotate in the same direction under the bi-directional air flows. A numerical model established in Fluent is validated by the corresponding experimental results. The flow fields, pressure distribution and dimensionless evaluating coefficients can be calculated and analyzed. Effects of the rotor solidity varying with the change of blade number are investigated and the suitable solidity value is recommended for different flow coefficients.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10975175, 90923002, and 21073222)the Postdoctoral Science Foundation of China (Grant No. 20100480645)+1 种基金the Postdoctoral Scientific Program of Shanghai, China (Grant No. 11R21418100)Chinese Academy of Sciences(Grant No. KJCX2-EW-N03)
文摘The structure and dynamics of water in a thick film on an ionic surface are studied by molecular dynamic simulations. We find that there is a dense monolayer of water molecules in the vicinity of the surface. Water molecules within this layer not only show an upright hydrogen-down orientation, but also an upright hydrogen-up orientation. Thus, water molecules in this layer can form hydrogen bonds with water molecules in the next layer. Therefore, the two-dimensional hydrogen bond network of the first layer is disrupted, mainly due to the 0 atoms in this layer, which are affected by the next layer and are unstable. Moreover, these water molecules exhibit delayed dynamic behavior with relatively long residence time compared with those bulk-like molecules in the other layers. Our study should be halpful to further understand the influence of water film thickness on the interfacial water at the solid-liquid interface.
基金supported by the Natural Science Foundation of Fujian Province (No. T08J0129)the Science and Technology Developing Foundation of Fuzhou University (No. 2008-XQ-001)2007-year New Century Talents Supporting Program of Fujian Province (No. XSJRC2007-17)
文摘A small amount of mineralizer MgO was added into Al2TiO5 synthesized from the sludge of aluminum factory to form Al(2-x)Mg(x+y)Ti(1-y)O(5-0.5x-y) solid solution and inhibit the decomposition of Al2TiO5 solid solution. It increased the content of Al2TiO5 solid solution and improved the thermal stability of materials. In this work,XRD and SEM methods were adopted to characterize the crystalline structure and microstructure of each kind of sample. Rietveld Quantification method was used to determine the content of crystalline phases in each sample. Results show as follows: the optimal addition concentration of MgO was 2.0%,and the corresponding content of Al2TiO5 solid solution which displayed irregular bulk shape was 100%; the addition of mineralizer MgO could enhance the flexural strength and thermal stability of Al2TiO5 solid solution materials. The optimal addition concentration of MgO determined by performance analysis was 2.0%,and its corresponding retention rate of thermal-shock flexural strength was 86.4%. Structure analysis and performance analysis resulted in good accordance.