An adsorbent, Na1.6Al0.6Ti1.4(PO4)3 (or NATP), was prepared by controlled crystallization of glasses in the Na2O-Al2O3-CaO-TiO2-P2O5 system. The crystalline phases characterized by X-ray diffraction (XRD) show t...An adsorbent, Na1.6Al0.6Ti1.4(PO4)3 (or NATP), was prepared by controlled crystallization of glasses in the Na2O-Al2O3-CaO-TiO2-P2O5 system. The crystalline phases characterized by X-ray diffraction (XRD) show that the sample glasses crystallizes into two phases, i.e. NATP and Ca9Al(PO4)7, while the Ca9Al(PO4)7 phase can be leached selectively with HCl, leaving a massive number of pores in the material. Through the experimental research, the effects of contact time, solution pH, and the initial concentration of Na+on the cation exchange properties were investigated. The batch sorption kinetics and equilibria can be described by Pseudo-second-order kinetic equations and Langmuir isotherm equations respectively. Furthermore, the experiments with an industrial solution show that the removal rate of sodium from industrial (NH4)2WO4 is higher than 97%. Cycle experiment also shows that the NATP has a good cyclic performance.展开更多
A mathematical model for simulating concentric-bed and other components of molecular sieve oxygen concentrator is established. In the model, the binary Langmuir equilibrium adsorption equation is adopted to describe t...A mathematical model for simulating concentric-bed and other components of molecular sieve oxygen concentrator is established. In the model, the binary Langmuir equilibrium adsorption equation is adopted to describe the adsorption performance of the adsorbent, the linear driving force (LDF) model is used to describe the mass transfer rate, and the thermal effect during adsorption is considered. The finite difference method is used in simulation and comparison. Numerical results have a reasonable agreement with the experimental research.展开更多
The breast cancer is the most common cause of cancer death in women. To establish an early stage in situ imaging of breast cancer cells, green quantum dots (QDs) are used as a fluorescent signal generator. The QDs b...The breast cancer is the most common cause of cancer death in women. To establish an early stage in situ imaging of breast cancer cells, green quantum dots (QDs) are used as a fluorescent signal generator. The QDs based imaging of breast cancer cells involves anti-HER2/neu antibody for labeling the over expressed HER2 on the surface of breast cancer cells. The complete assay involves breast cancer cells, biotin labeled antibody and streptavidin conjugated QDs. The breast cancer cells are grown in culture plates and exposed to the biotin labeled antibodies, and then exposed to streptavidin labeled QDs to utilize the strong and stable biotin-streptavidin interaction. Fluorescent images of the complete assay for breast cancer cells are evaluated on a microscope with a UV light source. Results show that the breast cancer cells in the complete assay are used as fluorescent cells with brighter signals compared with those labeled by the organic dye using similar parameters and the same number of cells.展开更多
The kinetic characteristics of P adsorption and desorption by organo-mineral colloidal complexes (OMC)were studied using acid, calcareous and neutral purple paddy soils taken from Chongqing and Sichuan, China.The resu...The kinetic characteristics of P adsorption and desorption by organo-mineral colloidal complexes (OMC)were studied using acid, calcareous and neutral purple paddy soils taken from Chongqing and Sichuan, China.The results showed that the P adsorption capacity of the organo-mineral colloidal complexes differed with the soil types, being higher for the acid and calcareous purple soils than for the neutral purple soils. Partial removal of the organic matter increased the adsorption capacity of the colloidal complexes. A very significant positive correlation was found between the amounts of P desorbed from OMC and the P saturation degrees.The P adsorption reaction was quick at the early stage and slowed later. The raise of temperature increased P adsorption capacity and P adsorption rate of the colloidal complexes. The adsorption processes could be described by the Elovich equation.展开更多
Activated carbon samples were developed from coal samples obtained from a coal mine, rat (Zonguldak, Turkey) and anthracite (Siberia, Russia), applying pyrolysis in a temperature range of 600-900 ℃ under N2 flow,...Activated carbon samples were developed from coal samples obtained from a coal mine, rat (Zonguldak, Turkey) and anthracite (Siberia, Russia), applying pyrolysis in a temperature range of 600-900 ℃ under N2 flow, and activation using chemical agents such as KOH, NH4Cl, ZnCl2 at 650 ℃. Nitrogen adsorption at low temperature (77 K) was used to characterize the activated carbon samples, and their pore structure properties including pore volume, pore diameter and pore size distribution were determined by means of the t-plots and DFT methods. The surface area values were higher for rat coal samples than for anthracite one, and for the rat coal samples treated with KOH + NH4Cl + ZnCl2 at 650 °C [Rat650(2)] there are highest surface area and total pore volume, 315.6 m2·g^-1 and 0.156 ml·g^-1, respectively. The highest value of the hydrogen sorption capacity was found as 0.71% (by mass) for the rat coal sample obtained by KOH + ZnCl2 treatment at 650 °C [Rat650(1)].展开更多
[Objective] In this study, the feasibility of resins to extract antibacterial substances in ferrfientation broth of Micromonospora carbonacea JXNU-1 was investigated. Various parameters including the type of resin, th...[Objective] In this study, the feasibility of resins to extract antibacterial substances in ferrfientation broth of Micromonospora carbonacea JXNU-1 was investigated. Various parameters including the type of resin, the time of adsorption and the initial pH on the extraction efficiency were investigated and optimized. [Method] The antibacterial activity of antibiotics was determined by agar diffusion method. [Result] The 717 anion resin was selected as the optimal, and its adsorption capacity reached 1 221 U/g within 2.5 h at the acidic range of pH (pH 5). The Freundlich model was fit for the adsorption model of the 717 anion resin for antibiotics. [Conclusion] The results laid the foundation for further separating and purifying antibiotics in fermentation broth of Micromonospora carbonacea JXNU-1.展开更多
The isotherm,mechanism and kinetics of carbon tetrachloride(CT) adsorption by polyacrylonitrile-based activated carbon fiber(PAN-ACF) were investigated in batch reactors and a continuous flow reactor,and the regenerat...The isotherm,mechanism and kinetics of carbon tetrachloride(CT) adsorption by polyacrylonitrile-based activated carbon fiber(PAN-ACF) were investigated in batch reactors and a continuous flow reactor,and the regeneration of PAN-ACF was also studied.Freundlich and Dubinin-Radushkevich(D-R) adsorption equations can well describe the adsorption isotherm.CT is mainly adsorbed on the exterior surface of PAN-ACF with low boundary layer effect and rate-controlling step of intra-particle diffusion.The adsorption dynamics in the batch reactor well fits with the pseudo-first-order model,and the breakthrough curves in the continuous flow reactor can be well described by the Yoon-Nelson model.The ACF can be recycled through thermal regeneration,whereas the adsorption capacity decreases from 7.87 to 4.98 mg/g after the fourth regeneration.78%-94%of CT can be removed from the wastewater of a fluorine chemical plant on a pilot scale,which confirms the efficacy of ACF under industrial conditions.The results indicate that PAN-ACF is applicable to CT removal from wastewater.展开更多
The paper presents a Monte Carlo simulation to study the adsorption characteristics of methane molecule on coal slit pores from different aspects.Firstly,a physical model of adsorption and desorption of methane molecu...The paper presents a Monte Carlo simulation to study the adsorption characteristics of methane molecule on coal slit pores from different aspects.Firstly,a physical model of adsorption and desorption of methane molecules on micropores was established.Secondly,a grand canonical ensemble was introduced as the Monte Carlo simulation system.Thirdly,based on the model and system,the molecule simulation program was developed with VC++6.0 to simulate the isothermal adsorption relationship between the amount of molecule absorption and the factors affecting it.Lastly,the numerically simulated results were compared with measured results of adsorption coal samples of two different coal mines with a laboratory gas absorption instrument.The results show that the molecule simulations of the adsorption constants,the adsorption quantity,and the isothermal adsorption curve at the same and different coal temperatures were in good agreement with those measured in the experiments,indicating that it is feasible to use the established model and the Monte Carlo molecule simulation to study the adsorption characteristics of methane molecules in coal.展开更多
Investigation of phosphorus (P) sorption-desorption characteristics of drainage ditch sediments is important for better understanding on sediment P transport behaviors in ditches. Surface ditch sediment samples were c...Investigation of phosphorus (P) sorption-desorption characteristics of drainage ditch sediments is important for better understanding on sediment P transport behaviors in ditches. Surface ditch sediment samples were collected from headwater sub-catchment of forestland, sloping cropland, paddy field, and residential area in a representative catchment in the central Sichuan Basin. These sediment samples were used for determination of P sorption-desorption characteristics by a batch equilibrium technique. Results showed that the maximum P sorption capacities (Qm) in the sediments ranged from 159.7 to 263.7 mg/kg, while higher Qm were observed in the ditch sediments from the paddy fields. The Qm was significantly and positively correlated with oxalate-extractable Fe and Al oxides (r=0.97 and 0.98, p < 0.01), clay fraction (r = 0.78, p < 0.05) and organic matter (r = 0.95, p < 0.01). Sediment pH, clay and organic matter influenced the P sorption through amorphous Fe and Al oxides. CaCO3 content was negatively correlated with the Qm (r = -0.83, p < 0.05), implying that saturated CaCO3 (> 50 g/kg) would not increase P sorption capacity in the ditch sediments. The ditch sediments featured a linear desorption curve, suggesting that P release risk would be enhanced with the increase of the P adsorption. The P desorption rate was positively correlated with Olsen P (r = 0.94, p < 0.01), but negatively related to the fine particle-size fractions (r = -0.92, p < 0.01), the sum of the amorphous Fe and Al oxides (r = -0.67, p < 0.05) and the P sorption capacity (r = -0.59, p < 0.05). The ditch sediments from residential area had a higher P release risk than that from the other ditches of forestland, sloping cropland and paddy field. The P sorption index (PSI) derived from single-point measurement was significantly correlated with the P sorption capacity (r = 0.99, p < 0.01), and could be used for estimating Qm as 1.64 times PSI plus 24.0 (Qm = 1.64 PSI + 24.0) for similar sediments with highly calcareous soils and sediments. Ditch cleaning and sediment removal for the ditch in residential area were recommended in this area to reduce the P release risk.展开更多
Crosslinked N, O-carboxymethyl chitosan resins which can selectively adsorb triglyceride, were prepared by the reaction of N, O- carboxymethyl chitosan with glutaraldehyde solution. Adsorption experiments were perform...Crosslinked N, O-carboxymethyl chitosan resins which can selectively adsorb triglyceride, were prepared by the reaction of N, O- carboxymethyl chitosan with glutaraldehyde solution. Adsorption experiments were performed by adding the resins to the serum. The results showed that this type of adsorbent could cut down the concentration of triglyceride in serum by 56. 4% (3. 35mg/gresin ) at most, while concentration of the total protein (TP ) decreased only by 10. 9% at least, so this novel adsorbent can be used to cure hypertriglyceridemia by hemoperfusion in the future.展开更多
To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechani...To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechanisms within a shale gas reservoir exploited by a horizontal well were thoroughly investigated, which took diffusion, adsorption/desorption and Darcy flow into account. The characteristics of diffusion in nano-scale pores in matrix and desorption on the matrix surface were both considered in the improved differential equations for seepage flow. By integrating the Langmuir isotherm desorption items into the new total dimensionless compression coefficient in matrix, the transport function and seepage flow could be formalized, simplified and consistent with the conventional form of diffusion equation. Furthermore, by utilizing the Laplace change and Sethfest inversion changes, the calculated results were obtained and further discussions indicated that transfer mechanisms were influenced by diffusion, adsorption/desorption. The research shows that when the matrix permeability is closed to magnitude of 10^-9D, the matrix flow only occurs near the surfacial matrix; as to the actual production, the central matrix blocks are barely involved in the production; the closer to the surface of matrix, the lower the pressure is and the more obvious the diffusion effect is; the behavior of adsorption/desorption can increase the matrix flow rate significantly and slow down the pressure of horizontal well obviously.展开更多
The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics...The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics, micro structure, chemical functional groups, re-adsorption properties, and pyrolysis characteristics of the dried coal were respectively analyzed. Results indicated that for typical Chinese lignite studied in this paper, 915 MHz microwave drying was 7.8 times faster than that of the hot air drying. After industrial microwave drying, the sample possessed much higher total specific surface area and specific pore volume than that of air dried sample. The oxygen functional groups and re-adsorption ratio of microwave irradiated coal decreased, showing weakened hydrophilicity. Moreover, during the pyrolysis of the coal dried by hot air and microwave, the yield of tar largely increased from 1.3% to 8.5% and the gas production increased correspondingly. The composition of the tar was also furtherly analyzed, results indicated that Miscellaneous hydrocarbons(HCs) were the main component of the tar, and microwave irradiation can reduce the fraction of polycyclic aromatic hydrocarbons(PAHs) from 26.4% to 22.7%.展开更多
The influence of small organics on the adsorption characteristics of activated carbon produced from industrial pyrolytic tire char(APTC)for malachite green(MG) was investigated by a batch method. Phenol was chosen as ...The influence of small organics on the adsorption characteristics of activated carbon produced from industrial pyrolytic tire char(APTC)for malachite green(MG) was investigated by a batch method. Phenol was chosen as the representative of small organics. The effects of phenol on adsorption equilibrium, kinetics and thermodynamics were studied systematically. The results indicate that APTC is a potential adsorbent for MG. The presence of phenol decreases the adsorption capacity of APTC for MG, but improves the rate of adsorption, while the adsorption characteristics, such as equilibrium, kinetics and thermodynamics are not affected by phenol. The adsorption equilibrium data follow Langmuir isotherm and the kinetic data are well described by the pseudo-second-order kinetic model. The adsorption process follows intra-particle diffusion model and the adsorption rate is determined by more than one process. Thermodynamic study shows that the adsorption is an endothermic and spontaneous physisorption process.展开更多
In this work we investigated the effect of nitric acid concentration on the pore structure,surface chemistry and liquid phase adsorption of olive stone based activated carbon prepared by mixing process using phosphori...In this work we investigated the effect of nitric acid concentration on the pore structure,surface chemistry and liquid phase adsorption of olive stone based activated carbon prepared by mixing process using phosphoric acid and steam as activating agents.Chemicals and textural characterization show that the increase of HNO3concentration increases considerably the total acidic groups but decreases specific surface area and pore volume.The study of adsorption in aqueous solutions of two organics,phenol and methylene blue,on raw and oxidized activated carbon indicates that the treatment of mixed activated carbon with different concentrations of nitric acid improves the adsorbent capacity for methylene blue at HNO3concentrations less or equal to 2 mol·L 1,while it has a negative effect on phenol adsorption.展开更多
Several 1,4-benzenedicarbonyl thiourea resins (BTR) were synthesized through interfacial polymerization between 1,4- benzenedicarbonyl diisothiocyanate and polyamine. Their structures were confirmed by FT-IR. The ad...Several 1,4-benzenedicarbonyl thiourea resins (BTR) were synthesized through interfacial polymerization between 1,4- benzenedicarbonyl diisothiocyanate and polyamine. Their structures were confirmed by FT-IR. The adsorption properties (including the effect of adsorption time, pH, initial concentrations and temperature) of BTR-1, BTR-2 and BTR-3 for Ag(I) were investigated by batch tests. The results show that the adsorption equilibria of BTR-1, BTR-2, BTR-3 for Ag(I) are achieved after about 10 h. Their equilibrium adsorption capacities are 7.11, 6.75 and 6.23, respectively, and the adsorption process accords with G. E. Boyd equation and Langmuir adsorption isotherm as well. The adsorption capacities increase with the increase ofpH (the highest uptake values are observed at pH being about 6-7). The thermodynamic parameters of BTR-1 were calculated. The results show that ΔH^ and ΔS^ are 6 958.8 J/mol and 64.28 J/(mol.K), respectively, and ΔG^ at 20, 30, 40 and 50 ℃ are -11.79, -12.52, -13.16 and -13.8 kJ/mol, respectively. The silver-loaded resins can be quantitatively eluted by a solution containing 6% thiourea in 1 mol/L HNO3.展开更多
AIM: To isolate and identify the biological characteristics of human colon cancer stem cells (SW1116 cells) and further study their proteome. METHODS: SW1116 cells were isolated and cultured with a serum-free medi...AIM: To isolate and identify the biological characteristics of human colon cancer stem cells (SW1116 cells) and further study their proteome. METHODS: SW1116 cells were isolated and cultured with a serum-free medium (SFM). Sphere formation was assayed to observe the formation of colon cancer stem cell spheres. SW1116 cells were inoculated into a serum-containing medium for observing their differentiation characteristics. Proliferation curve and cross-resistance of SWl116 cells to different drugs were detected by MTT. Percentage of SP cells in SW1116 cells was detected with Hoechst33342 staining. Telomerase activity in SW1116cells was checked by polymerase chain reaction (PCR)-enzyme linked immunosorbent assay. Expressions of stem cell relevant genes and proteins were detected by reverse transcription-PCR and Western blot, respectively. Total protein was isolated from SW1116 cells by two-dimensional gel electrophoresis (2-DE) and differentially expressed proteins were identified by tandem mass spectrometry (MALDI-TOF/TOF). RESULTS: The isolated SW1116 cells presented as spheroid and suspension growths in SFM with a strong self-renewal, proliferation, differentiation and drug-resistance ability. The percentage of SP cells in SW1116 cells was 38.9%. The SW1116 cells co-expressed the CD133 and CD29 proteins. The telomerase activity in SW1116 cells was increased. The expressions of different stem cell relevant genes and proteins were detected. The proteomic analysis showed that the 26 protein spots were differently expressed in SW1116 cells and 10 protein spots were identified as ubiquitin fusion- degradation l-like protein, nuclear chloride channel protein, tubulin 13, Raichu404X, stratifin, F-actin cap- ping protein α-1 subunit, eukaryotic translation elongation factor 1 delta isoform 2, hypothetical protein, glyceraldehyde-3-phosphate dehydrogenase and guanine nucleotide binding protein 13 polypeptide 2-like 1, respectively. CONCLUSION: SW1116 cells are biologically characterized by self-renewal, proliferation and differentiation, and the differently expressed proteins in SW1116 cells may be essential for isolating cancer stem cells.展开更多
High phosphate sorption constitutes a critical impediment to agricultural use of Andosols in the volcanic highlands of Central African Great Lakes region. A laboratory experiment was conducted on soil samples collecte...High phosphate sorption constitutes a critical impediment to agricultural use of Andosols in the volcanic highlands of Central African Great Lakes region. A laboratory experiment was conducted on soil samples collected from an Andosol amended with a factorial combination of lime and P (phosphorus) fertiliser to determine the P sorption characteristics and derive parameter estimates relevant in the prediction and management of P in the Andosols. The potential for sorption of additional P and its binding intensity were evaluated by applying the two-surface Langmuir model to sorption isotherms. The calculated P sorption maxima ranged from 1,667 mg·kg^-1 to 10,000 mg·kg^-1 representing about 95% of the P applied to the soil. The external P requirement ranged from 1,492 mgP·kg^-1 to 2,760 mgP.kgl which is further evidence that the studied Andosols are high P sorbers. There was no significant effect of lime and P rates on P sorption capacity of the Andosols. Exchangeable iron was highly correlated with P sorption maxima b2 (r = 0.98) on the high energy sites, whereas cation exchange capacity was negatively correlated with P sorption maxima bl (r = 0.999) and positively correlated with P binding energy K1 (r = 0.998) on the low energy sites.展开更多
A low-cost adsorbent was prepared from sludge and straw by pyrolysis in a dried state with the surface area of the adsorbent of 829.49 ma. g-l, micropore volume of 0.176 cm2·g-1 and average pore radius of 5.0 nm....A low-cost adsorbent was prepared from sludge and straw by pyrolysis in a dried state with the surface area of the adsorbent of 829.49 ma. g-l, micropore volume of 0.176 cm2·g-1 and average pore radius of 5.0 nm. The kinetic, equilibrium isotherm and thermodynamic characteristics of trisodium 1-(1-naphthylazo)-2-hydroxynaphthalene- 4',6,8-trisulphonate (acid scarlet 3R) onto the adsorbent from sludge and straw were investigated. The results indicated that the pseudo second order adsorption was the predominant adsorption mechanism of acid scarlet 3R. Thus, the adsorption phenomenon was suggested as a chemical process. The adsorption data were fitted better with Langmuir model than Freundlich model, indicating that the adsorption of acid scarlet 3R belonged to the monolayer adsorption and mainly occurred in micropores.展开更多
Using self-developed gas-seepage experimental installation,under the sameeffective stress conditions,coal permeability experiments on different adsorption characteristicsof gases,different temperatures and different g...Using self-developed gas-seepage experimental installation,under the sameeffective stress conditions,coal permeability experiments on different adsorption characteristicsof gases,different temperatures and different gas adsorption contents were performed,and the influence law of adsorption on coal permeability was studied.At the sametime,experimental analogy showed clearly that gas drawing plucks the permeability variationlaw.The results show that adsorption has a major impact on coal permeability.Thegreater the adsorption,the more the gas adsorption capacity and the coal permeabilitybecomes smaller.Permeability becomes smaller along with confining of pressure andtemperature,and this is in accord with local practice results.展开更多
基金Project(2012AA063205)supported by the High-tech Research and Development Program of China
文摘An adsorbent, Na1.6Al0.6Ti1.4(PO4)3 (or NATP), was prepared by controlled crystallization of glasses in the Na2O-Al2O3-CaO-TiO2-P2O5 system. The crystalline phases characterized by X-ray diffraction (XRD) show that the sample glasses crystallizes into two phases, i.e. NATP and Ca9Al(PO4)7, while the Ca9Al(PO4)7 phase can be leached selectively with HCl, leaving a massive number of pores in the material. Through the experimental research, the effects of contact time, solution pH, and the initial concentration of Na+on the cation exchange properties were investigated. The batch sorption kinetics and equilibria can be described by Pseudo-second-order kinetic equations and Langmuir isotherm equations respectively. Furthermore, the experiments with an industrial solution show that the removal rate of sodium from industrial (NH4)2WO4 is higher than 97%. Cycle experiment also shows that the NATP has a good cyclic performance.
文摘A mathematical model for simulating concentric-bed and other components of molecular sieve oxygen concentrator is established. In the model, the binary Langmuir equilibrium adsorption equation is adopted to describe the adsorption performance of the adsorbent, the linear driving force (LDF) model is used to describe the mass transfer rate, and the thermal effect during adsorption is considered. The finite difference method is used in simulation and comparison. Numerical results have a reasonable agreement with the experimental research.
基金Supported by the Foundation for Cultivating the Excellent Doctoral Dissertation of Jiangxi Province of China (YBP08A03)~~
文摘The breast cancer is the most common cause of cancer death in women. To establish an early stage in situ imaging of breast cancer cells, green quantum dots (QDs) are used as a fluorescent signal generator. The QDs based imaging of breast cancer cells involves anti-HER2/neu antibody for labeling the over expressed HER2 on the surface of breast cancer cells. The complete assay involves breast cancer cells, biotin labeled antibody and streptavidin conjugated QDs. The breast cancer cells are grown in culture plates and exposed to the biotin labeled antibodies, and then exposed to streptavidin labeled QDs to utilize the strong and stable biotin-streptavidin interaction. Fluorescent images of the complete assay for breast cancer cells are evaluated on a microscope with a UV light source. Results show that the breast cancer cells in the complete assay are used as fluorescent cells with brighter signals compared with those labeled by the organic dye using similar parameters and the same number of cells.
基金the Applied Science Foundation of the Science and Technology Commission of Chongqing,China.
文摘The kinetic characteristics of P adsorption and desorption by organo-mineral colloidal complexes (OMC)were studied using acid, calcareous and neutral purple paddy soils taken from Chongqing and Sichuan, China.The results showed that the P adsorption capacity of the organo-mineral colloidal complexes differed with the soil types, being higher for the acid and calcareous purple soils than for the neutral purple soils. Partial removal of the organic matter increased the adsorption capacity of the colloidal complexes. A very significant positive correlation was found between the amounts of P desorbed from OMC and the P saturation degrees.The P adsorption reaction was quick at the early stage and slowed later. The raise of temperature increased P adsorption capacity and P adsorption rate of the colloidal complexes. The adsorption processes could be described by the Elovich equation.
基金provided by the project DPT2002K120640 funded by State Planning Organization (DPT), Turkey
文摘Activated carbon samples were developed from coal samples obtained from a coal mine, rat (Zonguldak, Turkey) and anthracite (Siberia, Russia), applying pyrolysis in a temperature range of 600-900 ℃ under N2 flow, and activation using chemical agents such as KOH, NH4Cl, ZnCl2 at 650 ℃. Nitrogen adsorption at low temperature (77 K) was used to characterize the activated carbon samples, and their pore structure properties including pore volume, pore diameter and pore size distribution were determined by means of the t-plots and DFT methods. The surface area values were higher for rat coal samples than for anthracite one, and for the rat coal samples treated with KOH + NH4Cl + ZnCl2 at 650 °C [Rat650(2)] there are highest surface area and total pore volume, 315.6 m2·g^-1 and 0.156 ml·g^-1, respectively. The highest value of the hydrogen sorption capacity was found as 0.71% (by mass) for the rat coal sample obtained by KOH + ZnCl2 treatment at 650 °C [Rat650(1)].
基金Supported by the National Natural Science Foundation of China(31360018,31160029)the Natural Science Foundation of Jiangxi Province(20132BAB204007,20122BAB204008)+1 种基金Science and Technology Planning Project from Educational Commission of Jiangxi Province(GJJ12181)Special Fund for Agro-scientific Research in the Public Interest(201203072)~~
文摘[Objective] In this study, the feasibility of resins to extract antibacterial substances in ferrfientation broth of Micromonospora carbonacea JXNU-1 was investigated. Various parameters including the type of resin, the time of adsorption and the initial pH on the extraction efficiency were investigated and optimized. [Method] The antibacterial activity of antibiotics was determined by agar diffusion method. [Result] The 717 anion resin was selected as the optimal, and its adsorption capacity reached 1 221 U/g within 2.5 h at the acidic range of pH (pH 5). The Freundlich model was fit for the adsorption model of the 717 anion resin for antibiotics. [Conclusion] The results laid the foundation for further separating and purifying antibiotics in fermentation broth of Micromonospora carbonacea JXNU-1.
基金Project(2004C33068) supported by the Science and Technology Programs of Zhejiang Province,ChinaProject(20100933B17) supported by the Social Development and Science Research Program of Hangzhou,China
文摘The isotherm,mechanism and kinetics of carbon tetrachloride(CT) adsorption by polyacrylonitrile-based activated carbon fiber(PAN-ACF) were investigated in batch reactors and a continuous flow reactor,and the regeneration of PAN-ACF was also studied.Freundlich and Dubinin-Radushkevich(D-R) adsorption equations can well describe the adsorption isotherm.CT is mainly adsorbed on the exterior surface of PAN-ACF with low boundary layer effect and rate-controlling step of intra-particle diffusion.The adsorption dynamics in the batch reactor well fits with the pseudo-first-order model,and the breakthrough curves in the continuous flow reactor can be well described by the Yoon-Nelson model.The ACF can be recycled through thermal regeneration,whereas the adsorption capacity decreases from 7.87 to 4.98 mg/g after the fourth regeneration.78%-94%of CT can be removed from the wastewater of a fluorine chemical plant on a pilot scale,which confirms the efficacy of ACF under industrial conditions.The results indicate that PAN-ACF is applicable to CT removal from wastewater.
基金supported by the Industrial Research Project in Guizhou Science and Technology Bureau of China (GY(2011)No.3012)International Cooperation Projects in Guizhou Science and Technology Bureau of China (G(2009)No.700111)
文摘The paper presents a Monte Carlo simulation to study the adsorption characteristics of methane molecule on coal slit pores from different aspects.Firstly,a physical model of adsorption and desorption of methane molecules on micropores was established.Secondly,a grand canonical ensemble was introduced as the Monte Carlo simulation system.Thirdly,based on the model and system,the molecule simulation program was developed with VC++6.0 to simulate the isothermal adsorption relationship between the amount of molecule absorption and the factors affecting it.Lastly,the numerically simulated results were compared with measured results of adsorption coal samples of two different coal mines with a laboratory gas absorption instrument.The results show that the molecule simulations of the adsorption constants,the adsorption quantity,and the isothermal adsorption curve at the same and different coal temperatures were in good agreement with those measured in the experiments,indicating that it is feasible to use the established model and the Monte Carlo molecule simulation to study the adsorption characteristics of methane molecules in coal.
基金supported jointly by the CAS Action Plan for the Development of Western China (Grant No. KZCX2-XB3-09)the Key Project in the National Science and Technology Pillar Program of China (Grant No. 2011BAD31B03)
文摘Investigation of phosphorus (P) sorption-desorption characteristics of drainage ditch sediments is important for better understanding on sediment P transport behaviors in ditches. Surface ditch sediment samples were collected from headwater sub-catchment of forestland, sloping cropland, paddy field, and residential area in a representative catchment in the central Sichuan Basin. These sediment samples were used for determination of P sorption-desorption characteristics by a batch equilibrium technique. Results showed that the maximum P sorption capacities (Qm) in the sediments ranged from 159.7 to 263.7 mg/kg, while higher Qm were observed in the ditch sediments from the paddy fields. The Qm was significantly and positively correlated with oxalate-extractable Fe and Al oxides (r=0.97 and 0.98, p < 0.01), clay fraction (r = 0.78, p < 0.05) and organic matter (r = 0.95, p < 0.01). Sediment pH, clay and organic matter influenced the P sorption through amorphous Fe and Al oxides. CaCO3 content was negatively correlated with the Qm (r = -0.83, p < 0.05), implying that saturated CaCO3 (> 50 g/kg) would not increase P sorption capacity in the ditch sediments. The ditch sediments featured a linear desorption curve, suggesting that P release risk would be enhanced with the increase of the P adsorption. The P desorption rate was positively correlated with Olsen P (r = 0.94, p < 0.01), but negatively related to the fine particle-size fractions (r = -0.92, p < 0.01), the sum of the amorphous Fe and Al oxides (r = -0.67, p < 0.05) and the P sorption capacity (r = -0.59, p < 0.05). The ditch sediments from residential area had a higher P release risk than that from the other ditches of forestland, sloping cropland and paddy field. The P sorption index (PSI) derived from single-point measurement was significantly correlated with the P sorption capacity (r = 0.99, p < 0.01), and could be used for estimating Qm as 1.64 times PSI plus 24.0 (Qm = 1.64 PSI + 24.0) for similar sediments with highly calcareous soils and sediments. Ditch cleaning and sediment removal for the ditch in residential area were recommended in this area to reduce the P release risk.
文摘Crosslinked N, O-carboxymethyl chitosan resins which can selectively adsorb triglyceride, were prepared by the reaction of N, O- carboxymethyl chitosan with glutaraldehyde solution. Adsorption experiments were performed by adding the resins to the serum. The results showed that this type of adsorbent could cut down the concentration of triglyceride in serum by 56. 4% (3. 35mg/gresin ) at most, while concentration of the total protein (TP ) decreased only by 10. 9% at least, so this novel adsorbent can be used to cure hypertriglyceridemia by hemoperfusion in the future.
基金Foundation item: Project(PLN1129)supported by Opening Fund of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Southwest Petroleum University), China
文摘To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechanisms within a shale gas reservoir exploited by a horizontal well were thoroughly investigated, which took diffusion, adsorption/desorption and Darcy flow into account. The characteristics of diffusion in nano-scale pores in matrix and desorption on the matrix surface were both considered in the improved differential equations for seepage flow. By integrating the Langmuir isotherm desorption items into the new total dimensionless compression coefficient in matrix, the transport function and seepage flow could be formalized, simplified and consistent with the conventional form of diffusion equation. Furthermore, by utilizing the Laplace change and Sethfest inversion changes, the calculated results were obtained and further discussions indicated that transfer mechanisms were influenced by diffusion, adsorption/desorption. The research shows that when the matrix permeability is closed to magnitude of 10^-9D, the matrix flow only occurs near the surfacial matrix; as to the actual production, the central matrix blocks are barely involved in the production; the closer to the surface of matrix, the lower the pressure is and the more obvious the diffusion effect is; the behavior of adsorption/desorption can increase the matrix flow rate significantly and slow down the pressure of horizontal well obviously.
基金Supported by the National Natural Science Foundation of China(51621005)the Fundamental Research Funds for the Central Universities(2017FZA4013)
文摘The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics, micro structure, chemical functional groups, re-adsorption properties, and pyrolysis characteristics of the dried coal were respectively analyzed. Results indicated that for typical Chinese lignite studied in this paper, 915 MHz microwave drying was 7.8 times faster than that of the hot air drying. After industrial microwave drying, the sample possessed much higher total specific surface area and specific pore volume than that of air dried sample. The oxygen functional groups and re-adsorption ratio of microwave irradiated coal decreased, showing weakened hydrophilicity. Moreover, during the pyrolysis of the coal dried by hot air and microwave, the yield of tar largely increased from 1.3% to 8.5% and the gas production increased correspondingly. The composition of the tar was also furtherly analyzed, results indicated that Miscellaneous hydrocarbons(HCs) were the main component of the tar, and microwave irradiation can reduce the fraction of polycyclic aromatic hydrocarbons(PAHs) from 26.4% to 22.7%.
基金Supported by National Key Technologies R&D Program of China(No.2006BAC02A12)
文摘The influence of small organics on the adsorption characteristics of activated carbon produced from industrial pyrolytic tire char(APTC)for malachite green(MG) was investigated by a batch method. Phenol was chosen as the representative of small organics. The effects of phenol on adsorption equilibrium, kinetics and thermodynamics were studied systematically. The results indicate that APTC is a potential adsorbent for MG. The presence of phenol decreases the adsorption capacity of APTC for MG, but improves the rate of adsorption, while the adsorption characteristics, such as equilibrium, kinetics and thermodynamics are not affected by phenol. The adsorption equilibrium data follow Langmuir isotherm and the kinetic data are well described by the pseudo-second-order kinetic model. The adsorption process follows intra-particle diffusion model and the adsorption rate is determined by more than one process. Thermodynamic study shows that the adsorption is an endothermic and spontaneous physisorption process.
文摘In this work we investigated the effect of nitric acid concentration on the pore structure,surface chemistry and liquid phase adsorption of olive stone based activated carbon prepared by mixing process using phosphoric acid and steam as activating agents.Chemicals and textural characterization show that the increase of HNO3concentration increases considerably the total acidic groups but decreases specific surface area and pore volume.The study of adsorption in aqueous solutions of two organics,phenol and methylene blue,on raw and oxidized activated carbon indicates that the treatment of mixed activated carbon with different concentrations of nitric acid improves the adsorbent capacity for methylene blue at HNO3concentrations less or equal to 2 mol·L 1,while it has a negative effect on phenol adsorption.
基金Projects(20476105, 50604016) supported by the National Natural Science Foundation of China
文摘Several 1,4-benzenedicarbonyl thiourea resins (BTR) were synthesized through interfacial polymerization between 1,4- benzenedicarbonyl diisothiocyanate and polyamine. Their structures were confirmed by FT-IR. The adsorption properties (including the effect of adsorption time, pH, initial concentrations and temperature) of BTR-1, BTR-2 and BTR-3 for Ag(I) were investigated by batch tests. The results show that the adsorption equilibria of BTR-1, BTR-2, BTR-3 for Ag(I) are achieved after about 10 h. Their equilibrium adsorption capacities are 7.11, 6.75 and 6.23, respectively, and the adsorption process accords with G. E. Boyd equation and Langmuir adsorption isotherm as well. The adsorption capacities increase with the increase ofpH (the highest uptake values are observed at pH being about 6-7). The thermodynamic parameters of BTR-1 were calculated. The results show that ΔH^ and ΔS^ are 6 958.8 J/mol and 64.28 J/(mol.K), respectively, and ΔG^ at 20, 30, 40 and 50 ℃ are -11.79, -12.52, -13.16 and -13.8 kJ/mol, respectively. The silver-loaded resins can be quantitatively eluted by a solution containing 6% thiourea in 1 mol/L HNO3.
基金Supported by Medical Guidance Project of Shanghai Science Committee (No. 10411961800)Youth Science Fund of Fudan University (No. 08FQ49)
文摘AIM: To isolate and identify the biological characteristics of human colon cancer stem cells (SW1116 cells) and further study their proteome. METHODS: SW1116 cells were isolated and cultured with a serum-free medium (SFM). Sphere formation was assayed to observe the formation of colon cancer stem cell spheres. SW1116 cells were inoculated into a serum-containing medium for observing their differentiation characteristics. Proliferation curve and cross-resistance of SWl116 cells to different drugs were detected by MTT. Percentage of SP cells in SW1116 cells was detected with Hoechst33342 staining. Telomerase activity in SW1116cells was checked by polymerase chain reaction (PCR)-enzyme linked immunosorbent assay. Expressions of stem cell relevant genes and proteins were detected by reverse transcription-PCR and Western blot, respectively. Total protein was isolated from SW1116 cells by two-dimensional gel electrophoresis (2-DE) and differentially expressed proteins were identified by tandem mass spectrometry (MALDI-TOF/TOF). RESULTS: The isolated SW1116 cells presented as spheroid and suspension growths in SFM with a strong self-renewal, proliferation, differentiation and drug-resistance ability. The percentage of SP cells in SW1116 cells was 38.9%. The SW1116 cells co-expressed the CD133 and CD29 proteins. The telomerase activity in SW1116 cells was increased. The expressions of different stem cell relevant genes and proteins were detected. The proteomic analysis showed that the 26 protein spots were differently expressed in SW1116 cells and 10 protein spots were identified as ubiquitin fusion- degradation l-like protein, nuclear chloride channel protein, tubulin 13, Raichu404X, stratifin, F-actin cap- ping protein α-1 subunit, eukaryotic translation elongation factor 1 delta isoform 2, hypothetical protein, glyceraldehyde-3-phosphate dehydrogenase and guanine nucleotide binding protein 13 polypeptide 2-like 1, respectively. CONCLUSION: SW1116 cells are biologically characterized by self-renewal, proliferation and differentiation, and the differently expressed proteins in SW1116 cells may be essential for isolating cancer stem cells.
文摘High phosphate sorption constitutes a critical impediment to agricultural use of Andosols in the volcanic highlands of Central African Great Lakes region. A laboratory experiment was conducted on soil samples collected from an Andosol amended with a factorial combination of lime and P (phosphorus) fertiliser to determine the P sorption characteristics and derive parameter estimates relevant in the prediction and management of P in the Andosols. The potential for sorption of additional P and its binding intensity were evaluated by applying the two-surface Langmuir model to sorption isotherms. The calculated P sorption maxima ranged from 1,667 mg·kg^-1 to 10,000 mg·kg^-1 representing about 95% of the P applied to the soil. The external P requirement ranged from 1,492 mgP·kg^-1 to 2,760 mgP.kgl which is further evidence that the studied Andosols are high P sorbers. There was no significant effect of lime and P rates on P sorption capacity of the Andosols. Exchangeable iron was highly correlated with P sorption maxima b2 (r = 0.98) on the high energy sites, whereas cation exchange capacity was negatively correlated with P sorption maxima bl (r = 0.999) and positively correlated with P binding energy K1 (r = 0.998) on the low energy sites.
基金Supported by the Shanxi Science and Technology Agency Research Project(20100321085)the Scientific Research Foun-dation of the Shanxi Education Department(20111029)
文摘A low-cost adsorbent was prepared from sludge and straw by pyrolysis in a dried state with the surface area of the adsorbent of 829.49 ma. g-l, micropore volume of 0.176 cm2·g-1 and average pore radius of 5.0 nm. The kinetic, equilibrium isotherm and thermodynamic characteristics of trisodium 1-(1-naphthylazo)-2-hydroxynaphthalene- 4',6,8-trisulphonate (acid scarlet 3R) onto the adsorbent from sludge and straw were investigated. The results indicated that the pseudo second order adsorption was the predominant adsorption mechanism of acid scarlet 3R. Thus, the adsorption phenomenon was suggested as a chemical process. The adsorption data were fitted better with Langmuir model than Freundlich model, indicating that the adsorption of acid scarlet 3R belonged to the monolayer adsorption and mainly occurred in micropores.
文摘Using self-developed gas-seepage experimental installation,under the sameeffective stress conditions,coal permeability experiments on different adsorption characteristicsof gases,different temperatures and different gas adsorption contents were performed,and the influence law of adsorption on coal permeability was studied.At the sametime,experimental analogy showed clearly that gas drawing plucks the permeability variationlaw.The results show that adsorption has a major impact on coal permeability.Thegreater the adsorption,the more the gas adsorption capacity and the coal permeabilitybecomes smaller.Permeability becomes smaller along with confining of pressure andtemperature,and this is in accord with local practice results.