Western Jilin Province is a typical seasonal frost region, and is also one of the severest salinization areas of China. In this study, we aim to examine the saline soil in Da'an and Wukesong areas, western Jilin Prov...Western Jilin Province is a typical seasonal frost region, and is also one of the severest salinization areas of China. In this study, we aim to examine the saline soil in Da'an and Wukesong areas, western Jilin Province, and mainly analyze the granulometric composition and distribution of salt in soil profiles. Four sampling sites, two in Da'an and two in Wukesong respectively, are chosen for study. The granulometric composition, especially silt and clay content change in different sites and soil depths are analyzed. Analysis of total and components of soluble salt shows that the surface soil is weak carbonate saline, in which the main cation is Na+ and the main anion is HCO3-. The total amount of soluble salt presents a decreasing tendency with increasing depth. The comprehensive analysis ofgranulometric composition and soluble salt shows that the clay content and soluble salt content present similar variation tendency with an increase of depth.展开更多
A pot experiment was carried out on a marine saline soil to study the effect of initial soluble Na/Ca ratio of saline soil on the salinity tolerance of barley plant.The results showed that (1) the Na/Ca ratio affected...A pot experiment was carried out on a marine saline soil to study the effect of initial soluble Na/Ca ratio of saline soil on the salinity tolerance of barley plant.The results showed that (1) the Na/Ca ratio affected significantly the dry weight of the plant at an earlier stage of growth,the critical values of initial Na/Ca ratio at which the plant could grow normally on soils containing salts of 2.5,3.5 and 4.5g kg^-1 were 30,20 and 15,respectively;(2)smaller Na/Ca ratio resulted in a considerable decrease in Na accumulation but a great increase in K accumulation in the barley plant;and (3) the plasmallema of barley leaf were badly injured when the Na/Ca ratio was more than 30 and the increase of Na content of plant caused an exudation of K from the leaf cells.Some critical indexes were suggested for the cultivation of barley plant on marine saline soils and could be used as reference in the biological reclamation of marine saline soils.展开更多
Polycarboxylate(PC) superplasticizers with different chemical structures were synthesized through free radical co-polymerization reaction.A total organic carbon analyzer was used to investigate adsorption behaviors ...Polycarboxylate(PC) superplasticizers with different chemical structures were synthesized through free radical co-polymerization reaction.A total organic carbon analyzer was used to investigate adsorption behaviors of PCs,and to evaluate influences of soluble salts on absorption properties of PCs.It is found that adsorption ratios of PCs on cement particles decrease greatly with the addition of Na2SO4;the adsorption ratio of ethers PC with Hydroxyethyl methacrylate(HEMA) group first increases then decreases with the addition of NaCl;the adsorption ratio of esters PC with short side chains first decreases then increases,while the adsorption ratio of ethers PC with HEMA group decreases with the addition of CaCl2;the adsorption ratio of esters PC with short side chains decreases with the addition of Ca(NO3)2;AlCl3 causes the decrease of the adsorption ratio of ethers PC with HEMA group.展开更多
Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. Th...Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented, which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake. And secondly, with a model forming idea of transport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference, a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory. Meanwhile, the model was applied to model potassium/magnesium transport in Qarhan Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/ Magnesium in the mining of salt deposits in Qarhan Salt Lake.展开更多
The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na_2CO_3-NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 oC. The saturated amo...The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na_2CO_3-NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 oC. The saturated amount of dissolved ZnO in the molten salt remained constant at 0.02% and was unaffected by temperature; additionally, ZnO did not react with the molten salt. In contrast, the saturated amount of dissolved ZnS in the eutectic molten salt increased with increasing temperature, and the content of ZnS was 0.53% at 1000 oC. In addition, ZnS reacted with Na_2CO_3 above 900 oC to give ZnO. The sedimentation rates of these three species in the molten salt followed the order of Sb>ZnS>ZnO. It was thus concluded that ZnO is an appropriate sulfur-fixing agent for low-temperature Sb smelting in a Na_2CO_3-NaCl molten medium, and that the optimal smelting temperature is below 900 oC.展开更多
New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solu...New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains a H beside the OH groups formed in the ring-opening reactions.展开更多
In this article, the theoretical foundation for salts is given with an emphasis on the amount of drug in solution. Consideration is given for the solubility of the non-ionized form, acid dissociation constant and solu...In this article, the theoretical foundation for salts is given with an emphasis on the amount of drug in solution. Consideration is given for the solubility of the non-ionized form, acid dissociation constant and solubility product, which are the limiting constraints. For dissolution of nonionized drugs, the surface pH differs from the bulk pH, giving rise to a lower than expected rate. For salts, theoretical considerations are relatively complex, and an experimental approach to estimating the surface pH is more likely to be of value in predicting the dissolution rate. General guidelines are described for screening, preparing and characterizing drugs as salts, which critically depend on the goal of the product development.Thereafter, our work involving the preparation of salts as a means to generate aerosols from a solution is provided. The solubility of six structurally related compounds was determined in four acids. Thereafter, the amount of the compound in solution was determined as a function of pH, using the acid that provided the highest solubility. Because the pH required to achieve the needed concentration for aerosol generation was low, ammonia vapor was introduced into the air stream to neutralize aerosol droplets. Solvent was then removed from the aerosol by a silica column. The resulting aerosol had a concentration of 96 μg/l and a mass median particle size of 1.8 μm. The reported pharmacokinetic study substantiated the feasibility of evaluating its safety and efficacy of inhalation administration in the rat model.展开更多
Novel crystalline forms of ibuprofen(IBU) with 2-methylimidazole(2 MI) in a 1:1 molar ratio was synthesized by liquid-assisted grinding technique and characterized by single-crystal X-ray diffraction, infrared spectra...Novel crystalline forms of ibuprofen(IBU) with 2-methylimidazole(2 MI) in a 1:1 molar ratio was synthesized by liquid-assisted grinding technique and characterized by single-crystal X-ray diffraction, infrared spectral(IR), powder X-ray diffraction(PXRD),differential scanning calormetry(DSC) and Hirshfeld surface analysis. The structure of IBU-2 MI salt is assembled via N(1)–H(1)+···O1 and N(2)–H(2)+···O(2) hydrogen bonds to form the zigzag-like 1 D chain structure. The original purpose was to solve the pH-dependent solubility defect of ibuprofen, and the result of pH dependent solubility experiments showed that the IBU-2 MI salt had a better solubility at the wide range of pH 4.00 to 9.18. Furthermore, the solubility of IBU-2 MI salt exhibits a dramatic increase(30-fold) in aqueous mediums.展开更多
Based on the requirement of the new technology for producing potassium sulfate and N-Mg compound fertilizer,boussingaultite,by the reaction of the mineral shoenite from Kunteyi Salt Lake,Qinghai province,and the indus...Based on the requirement of the new technology for producing potassium sulfate and N-Mg compound fertilizer,boussingaultite,by the reaction of the mineral shoenite from Kunteyi Salt Lake,Qinghai province,and the industrial by-product ammonium sulfate,the solubilities of the quaternary system(NH_(4))_(2)SO_(4)-MgSO_(4)-K_(2)SO_(4)-H_(2)O at 25.0℃in the isothermal evaporation and crystallization process were measured using the isothermal evaporation method,and the corresponding phase diagrams were plotted.According to the diagram,this system contains six saturation points and six solid phase fields of crystallization,which correspond to(K1-m,(NH_(4))m)_(2)SO_(4),(NH_(4))_(2)SO_(4)·MgSO_(4)·6H_(2)O,K_(2)SO_(4)·MgSO_(4)·6H_(2)O,MgSO_(4)·6H_(2)O,(K1-n,(NH_(4))n)_(2)SO_(4)·MgSO_(4)·6H_(2)O and MgSO_(4)·7H_(2)O,respectively.By analyzing and calculating the isothermal evaporation and dissolution phase diagram of this quaternary system at 25.0℃,K_(2)SO_(4)and(NH_(4))_(2)SO_(4)·MgSO_(4)·6H_(2)O can be separated via K_(2)SO_(4)·MgSO_(4)·6H_(2)O and(NH_(4))_(2)SO_(4)as raw materials.Theoretical calculations about the proposed process were carried out and verified by experiment,which indicated that the yield of potassium sulfate was improved and the magnesium resources were fully utilized.展开更多
Background: When usual calcium consumption patterns were analysed most people in the U.S. and Europe consume less than the recommended daily allowance. Supplements and fortified foods offer alternative and additional ...Background: When usual calcium consumption patterns were analysed most people in the U.S. and Europe consume less than the recommended daily allowance. Supplements and fortified foods offer alternative and additional sources of calcium to traditional food. Calcium carbonate is the most common supplement but it is less soluble in water and, therefore, not suitable for enrichment of beverages. New organic calcium salts have a better solubility but less is known about their bioavailability. In the present study, we assessed the solubility and bioavailability of the new organic calcium salts, calcium lactate citrate and calcium lactate malate, in comparison to the traditional supplements, calcium carbonate and calcium gluconate. Design: Randomized, single-blind, four way cross-over study comparing single doses of 500 mg calcium in the form of four different calcium-salts. Subjects were advised to consume 25 μg vitamin D3 daily two weeks prior to the start of the study and during the whole study period. Subjects: 20 healthy young men, Methods: Blood samples were drawn immediately before and 2, 4, 6, 8, 12 and 24 h after ingestion of the calcium preparation. Concentration of total calcium and intact parathyroid hormone were measured in the serum. Urine was collected at baseline and during the intervals 0-3, 3-6, 9-15 and 15-24 h and excretion of calcium, sodium and creatinine was examined. Results: The tested new salts were easily water soluble, significantly better than calcium gluconate. Calcium carbonate is almost insoluble. The bioavailability of the four different calcium salts was found to be almost identical. The maximum total serum calcium increased by 7.6 % two hours after ingestion calcium lactate citrate, by 7.4 % after calcium lactate malate, by 5.5 % after calcium carbonate, and by 5.8 % after calcium gluconate. Intact parathyroid hormone concentration showed the expected depression for calcium lactate citrate, calcium lactate malate and calcium carbonate, whereas the serum level was significantly higher after ingestion of calcium gluconate. Conclusion: Given an almost equivalent bioavailability of the four tested calcium salts, we conclude that the new salts calcium lactate citrate and calcium lactate malate are well suited for fortification of beverages and thus to increase the average daily calcium intake.展开更多
The alumina solubility in the title system within the composition range of KR{m(K3AlF6)/[m(K3AlF6)+ m(Na3AlF6)]} 10%―50%, a ternary Na3AlF6-K3AlF6-AlF3 molten system with 23%―29%(mass fraction) AlF3 was inv...The alumina solubility in the title system within the composition range of KR{m(K3AlF6)/[m(K3AlF6)+ m(Na3AlF6)]} 10%―50%, a ternary Na3AlF6-K3AlF6-AlF3 molten system with 23%―29%(mass fraction) AlF3 was investigated by measuring the mass loss of a rotating sintered corundum disc. And the following empirical equation was derived when superheat degree was no more than 60 °C: w(Al2O3)sat=A×(T/1000)B, where A= –1.85774+ 26.754234w(AlF3)–0.3683–0.00783KR2.363+0.010266KR2.3048+0.7902w(AlF3)0.00652, B=112.4625–53.2567w(AlF3)0.4236+ 5.1079w(AlF3)0.9241+0.01542w(AlF3)1.3540. Considering both higher alumina solubility and not too high superheat de gree are required, alumina solubility of different compositions at not the same temperature but the same superheat degree was studied, which will be more industrial helpful for selecting prospective compositions. The results show that the composition deserved to be further tested in lower temperature cells is 10%―30% KR and 23%―26%(mass fraction) AlF3.展开更多
In order to provide data on diffusion coefficients and solubility constants of tritium in molten salts for the critical issue of tritium control in the Thorium Molten Salt Reactor(TMSR)program,a two-chamber permeabili...In order to provide data on diffusion coefficients and solubility constants of tritium in molten salts for the critical issue of tritium control in the Thorium Molten Salt Reactor(TMSR)program,a two-chamber permeability apparatus separated by a nickel plate had been developed for determining the permeability of hydrogen isotope in molten salts.Descriptions on the permeability apparatus,experimental procedure and the analytical method for determining the diffusivity and solubility of hydrogen isotope in molten salts were presented in this paper.To assess the performance of the apparatus,the blank tests without molten salt were conducted at300-700℃.The results showed that the nickel plate acting as the window for hydrogen isotope permeation in the apparatus seemed to have less effect on experiments of determining the permeability of hydrogen isotope in molten slat at 500-700℃.Furthermore,the applicability of the apparatus with molten salt was also evaluated experimentally,with test experiments of molten Flinak(LiF-NaF-KF)at 500℃,600℃and 700℃.Diffusion coefficients and solubility constants of hydrogen in molten Flinak can be derived from those test experiments,which were correlated to D_(Flinak-H)=7.06×10^(-5)e^(-54.9/(R_gT))m^2/s and s_(Flinak-H)=1.67×10^(-7)e^(27.0/(r_gt))mol-H_2/(m^3 Pa).展开更多
The solubility of ferroalloyed neodymium in molten salt containing neodymium trichloride and the de- pendence of solubility on temperature and composition of the melt are determined by means of electrochemical method....The solubility of ferroalloyed neodymium in molten salt containing neodymium trichloride and the de- pendence of solubility on temperature and composition of the melt are determined by means of electrochemical method.The data obtained are in good agreement with result of chemical analysis of the quenched molten salt samples.展开更多
Observation and experimental analysis of soluble salt deposit along four profiles across the strata deposited in Nihewan paleolake basin enabled us to recognize the nature and evolution stages of the Nihewan paleolake...Observation and experimental analysis of soluble salt deposit along four profiles across the strata deposited in Nihewan paleolake basin enabled us to recognize the nature and evolution stages of the Nihewan paleolake and its significance in stratigraphical division and pa-leo-environmental reconstruction. The Nihewan paleolake was at least a weak-saline to semi-saline lake and represents an intracontinental lake in the semi-arid region. The lower member of sedimentary strata in the paleolake contains gypsum layer and gypsum lamellae. Soluble salt is mainly composed of SO42- and Ca2+ ions, representing a trend of the paleolake evolvinginto a stage of sulfate lake. The upper member of the strata has predominantly Cl-, K+, and Na+ ions in soluble salt, indicating a starting development of the paleolake to chlorite lake, but no salt rock was deposited, indicating a drying trend of the area.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41372267,41402243)the State Key Program of National Natural Science Foundation of China(Grant No.41430642)
文摘Western Jilin Province is a typical seasonal frost region, and is also one of the severest salinization areas of China. In this study, we aim to examine the saline soil in Da'an and Wukesong areas, western Jilin Province, and mainly analyze the granulometric composition and distribution of salt in soil profiles. Four sampling sites, two in Da'an and two in Wukesong respectively, are chosen for study. The granulometric composition, especially silt and clay content change in different sites and soil depths are analyzed. Analysis of total and components of soluble salt shows that the surface soil is weak carbonate saline, in which the main cation is Na+ and the main anion is HCO3-. The total amount of soluble salt presents a decreasing tendency with increasing depth. The comprehensive analysis ofgranulometric composition and soluble salt shows that the clay content and soluble salt content present similar variation tendency with an increase of depth.
文摘A pot experiment was carried out on a marine saline soil to study the effect of initial soluble Na/Ca ratio of saline soil on the salinity tolerance of barley plant.The results showed that (1) the Na/Ca ratio affected significantly the dry weight of the plant at an earlier stage of growth,the critical values of initial Na/Ca ratio at which the plant could grow normally on soils containing salts of 2.5,3.5 and 4.5g kg^-1 were 30,20 and 15,respectively;(2)smaller Na/Ca ratio resulted in a considerable decrease in Na accumulation but a great increase in K accumulation in the barley plant;and (3) the plasmallema of barley leaf were badly injured when the Na/Ca ratio was more than 30 and the increase of Na content of plant caused an exudation of K from the leaf cells.Some critical indexes were suggested for the cultivation of barley plant on marine saline soils and could be used as reference in the biological reclamation of marine saline soils.
基金Funded by the National Natural Science Foundation of China(No. 50872151)
文摘Polycarboxylate(PC) superplasticizers with different chemical structures were synthesized through free radical co-polymerization reaction.A total organic carbon analyzer was used to investigate adsorption behaviors of PCs,and to evaluate influences of soluble salts on absorption properties of PCs.It is found that adsorption ratios of PCs on cement particles decrease greatly with the addition of Na2SO4;the adsorption ratio of ethers PC with Hydroxyethyl methacrylate(HEMA) group first increases then decreases with the addition of NaCl;the adsorption ratio of esters PC with short side chains first decreases then increases,while the adsorption ratio of ethers PC with HEMA group decreases with the addition of CaCl2;the adsorption ratio of esters PC with short side chains decreases with the addition of Ca(NO3)2;AlCl3 causes the decrease of the adsorption ratio of ethers PC with HEMA group.
基金the National Natural Science Foundation of China
文摘Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented, which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake. And secondly, with a model forming idea of transport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference, a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory. Meanwhile, the model was applied to model potassium/magnesium transport in Qarhan Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/ Magnesium in the mining of salt deposits in Qarhan Salt Lake.
基金Projects(51104128,51234009)supported by the National Natural Science Foundation of China
文摘The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na_2CO_3-NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 oC. The saturated amount of dissolved ZnO in the molten salt remained constant at 0.02% and was unaffected by temperature; additionally, ZnO did not react with the molten salt. In contrast, the saturated amount of dissolved ZnS in the eutectic molten salt increased with increasing temperature, and the content of ZnS was 0.53% at 1000 oC. In addition, ZnS reacted with Na_2CO_3 above 900 oC to give ZnO. The sedimentation rates of these three species in the molten salt followed the order of Sb>ZnS>ZnO. It was thus concluded that ZnO is an appropriate sulfur-fixing agent for low-temperature Sb smelting in a Na_2CO_3-NaCl molten medium, and that the optimal smelting temperature is below 900 oC.
文摘New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains a H beside the OH groups formed in the ring-opening reactions.
文摘In this article, the theoretical foundation for salts is given with an emphasis on the amount of drug in solution. Consideration is given for the solubility of the non-ionized form, acid dissociation constant and solubility product, which are the limiting constraints. For dissolution of nonionized drugs, the surface pH differs from the bulk pH, giving rise to a lower than expected rate. For salts, theoretical considerations are relatively complex, and an experimental approach to estimating the surface pH is more likely to be of value in predicting the dissolution rate. General guidelines are described for screening, preparing and characterizing drugs as salts, which critically depend on the goal of the product development.Thereafter, our work involving the preparation of salts as a means to generate aerosols from a solution is provided. The solubility of six structurally related compounds was determined in four acids. Thereafter, the amount of the compound in solution was determined as a function of pH, using the acid that provided the highest solubility. Because the pH required to achieve the needed concentration for aerosol generation was low, ammonia vapor was introduced into the air stream to neutralize aerosol droplets. Solvent was then removed from the aerosol by a silica column. The resulting aerosol had a concentration of 96 μg/l and a mass median particle size of 1.8 μm. The reported pharmacokinetic study substantiated the feasibility of evaluating its safety and efficacy of inhalation administration in the rat model.
基金supported by the Natural Science Foundation of Guangxi Province(No.2018GXNSFBA281167)Wuzhou University Foundation(No.2017A003 and 2017B015)
文摘Novel crystalline forms of ibuprofen(IBU) with 2-methylimidazole(2 MI) in a 1:1 molar ratio was synthesized by liquid-assisted grinding technique and characterized by single-crystal X-ray diffraction, infrared spectral(IR), powder X-ray diffraction(PXRD),differential scanning calormetry(DSC) and Hirshfeld surface analysis. The structure of IBU-2 MI salt is assembled via N(1)–H(1)+···O1 and N(2)–H(2)+···O(2) hydrogen bonds to form the zigzag-like 1 D chain structure. The original purpose was to solve the pH-dependent solubility defect of ibuprofen, and the result of pH dependent solubility experiments showed that the IBU-2 MI salt had a better solubility at the wide range of pH 4.00 to 9.18. Furthermore, the solubility of IBU-2 MI salt exhibits a dramatic increase(30-fold) in aqueous mediums.
基金This project was supported by the National Natural Science Foundation of China(grant No.21576066)the Natural Science Foundation of Hebei Province,China(No.B2017202268)the Research Fund Program of Guangdong Provincial Key Lab of Green Chemical Product Technology(No.GC201816).
文摘Based on the requirement of the new technology for producing potassium sulfate and N-Mg compound fertilizer,boussingaultite,by the reaction of the mineral shoenite from Kunteyi Salt Lake,Qinghai province,and the industrial by-product ammonium sulfate,the solubilities of the quaternary system(NH_(4))_(2)SO_(4)-MgSO_(4)-K_(2)SO_(4)-H_(2)O at 25.0℃in the isothermal evaporation and crystallization process were measured using the isothermal evaporation method,and the corresponding phase diagrams were plotted.According to the diagram,this system contains six saturation points and six solid phase fields of crystallization,which correspond to(K1-m,(NH_(4))m)_(2)SO_(4),(NH_(4))_(2)SO_(4)·MgSO_(4)·6H_(2)O,K_(2)SO_(4)·MgSO_(4)·6H_(2)O,MgSO_(4)·6H_(2)O,(K1-n,(NH_(4))n)_(2)SO_(4)·MgSO_(4)·6H_(2)O and MgSO_(4)·7H_(2)O,respectively.By analyzing and calculating the isothermal evaporation and dissolution phase diagram of this quaternary system at 25.0℃,K_(2)SO_(4)and(NH_(4))_(2)SO_(4)·MgSO_(4)·6H_(2)O can be separated via K_(2)SO_(4)·MgSO_(4)·6H_(2)O and(NH_(4))_(2)SO_(4)as raw materials.Theoretical calculations about the proposed process were carried out and verified by experiment,which indicated that the yield of potassium sulfate was improved and the magnesium resources were fully utilized.
文摘Background: When usual calcium consumption patterns were analysed most people in the U.S. and Europe consume less than the recommended daily allowance. Supplements and fortified foods offer alternative and additional sources of calcium to traditional food. Calcium carbonate is the most common supplement but it is less soluble in water and, therefore, not suitable for enrichment of beverages. New organic calcium salts have a better solubility but less is known about their bioavailability. In the present study, we assessed the solubility and bioavailability of the new organic calcium salts, calcium lactate citrate and calcium lactate malate, in comparison to the traditional supplements, calcium carbonate and calcium gluconate. Design: Randomized, single-blind, four way cross-over study comparing single doses of 500 mg calcium in the form of four different calcium-salts. Subjects were advised to consume 25 μg vitamin D3 daily two weeks prior to the start of the study and during the whole study period. Subjects: 20 healthy young men, Methods: Blood samples were drawn immediately before and 2, 4, 6, 8, 12 and 24 h after ingestion of the calcium preparation. Concentration of total calcium and intact parathyroid hormone were measured in the serum. Urine was collected at baseline and during the intervals 0-3, 3-6, 9-15 and 15-24 h and excretion of calcium, sodium and creatinine was examined. Results: The tested new salts were easily water soluble, significantly better than calcium gluconate. Calcium carbonate is almost insoluble. The bioavailability of the four different calcium salts was found to be almost identical. The maximum total serum calcium increased by 7.6 % two hours after ingestion calcium lactate citrate, by 7.4 % after calcium lactate malate, by 5.5 % after calcium carbonate, and by 5.8 % after calcium gluconate. Intact parathyroid hormone concentration showed the expected depression for calcium lactate citrate, calcium lactate malate and calcium carbonate, whereas the serum level was significantly higher after ingestion of calcium gluconate. Conclusion: Given an almost equivalent bioavailability of the four tested calcium salts, we conclude that the new salts calcium lactate citrate and calcium lactate malate are well suited for fortification of beverages and thus to increase the average daily calcium intake.
基金Supported by the National Basic Research Program of China(No.2005CB623703)the National High-Tech Research and Development Program of China(No.2008AA030503)
文摘The alumina solubility in the title system within the composition range of KR{m(K3AlF6)/[m(K3AlF6)+ m(Na3AlF6)]} 10%―50%, a ternary Na3AlF6-K3AlF6-AlF3 molten system with 23%―29%(mass fraction) AlF3 was investigated by measuring the mass loss of a rotating sintered corundum disc. And the following empirical equation was derived when superheat degree was no more than 60 °C: w(Al2O3)sat=A×(T/1000)B, where A= –1.85774+ 26.754234w(AlF3)–0.3683–0.00783KR2.363+0.010266KR2.3048+0.7902w(AlF3)0.00652, B=112.4625–53.2567w(AlF3)0.4236+ 5.1079w(AlF3)0.9241+0.01542w(AlF3)1.3540. Considering both higher alumina solubility and not too high superheat de gree are required, alumina solubility of different compositions at not the same temperature but the same superheat degree was studied, which will be more industrial helpful for selecting prospective compositions. The results show that the composition deserved to be further tested in lower temperature cells is 10%―30% KR and 23%―26%(mass fraction) AlF3.
文摘In order to provide data on diffusion coefficients and solubility constants of tritium in molten salts for the critical issue of tritium control in the Thorium Molten Salt Reactor(TMSR)program,a two-chamber permeability apparatus separated by a nickel plate had been developed for determining the permeability of hydrogen isotope in molten salts.Descriptions on the permeability apparatus,experimental procedure and the analytical method for determining the diffusivity and solubility of hydrogen isotope in molten salts were presented in this paper.To assess the performance of the apparatus,the blank tests without molten salt were conducted at300-700℃.The results showed that the nickel plate acting as the window for hydrogen isotope permeation in the apparatus seemed to have less effect on experiments of determining the permeability of hydrogen isotope in molten slat at 500-700℃.Furthermore,the applicability of the apparatus with molten salt was also evaluated experimentally,with test experiments of molten Flinak(LiF-NaF-KF)at 500℃,600℃and 700℃.Diffusion coefficients and solubility constants of hydrogen in molten Flinak can be derived from those test experiments,which were correlated to D_(Flinak-H)=7.06×10^(-5)e^(-54.9/(R_gT))m^2/s and s_(Flinak-H)=1.67×10^(-7)e^(27.0/(r_gt))mol-H_2/(m^3 Pa).
文摘The solubility of ferroalloyed neodymium in molten salt containing neodymium trichloride and the de- pendence of solubility on temperature and composition of the melt are determined by means of electrochemical method.The data obtained are in good agreement with result of chemical analysis of the quenched molten salt samples.
文摘Observation and experimental analysis of soluble salt deposit along four profiles across the strata deposited in Nihewan paleolake basin enabled us to recognize the nature and evolution stages of the Nihewan paleolake and its significance in stratigraphical division and pa-leo-environmental reconstruction. The Nihewan paleolake was at least a weak-saline to semi-saline lake and represents an intracontinental lake in the semi-arid region. The lower member of sedimentary strata in the paleolake contains gypsum layer and gypsum lamellae. Soluble salt is mainly composed of SO42- and Ca2+ ions, representing a trend of the paleolake evolvinginto a stage of sulfate lake. The upper member of the strata has predominantly Cl-, K+, and Na+ ions in soluble salt, indicating a starting development of the paleolake to chlorite lake, but no salt rock was deposited, indicating a drying trend of the area.