Surface morphology and inner structure of the dust were observed by ICP-AES, SEM-EDS and XRD to examine the strengthening measures of leaching potassium salt from the sintering dust by water. The results showed that t...Surface morphology and inner structure of the dust were observed by ICP-AES, SEM-EDS and XRD to examine the strengthening measures of leaching potassium salt from the sintering dust by water. The results showed that the main component of the sintering dust was iron-oxygen compound, with KCl adsorbed on its surface. Leaching experiments showed that the KCl in the ESP dust could be separated and recovered by water leaching and fractional crystallization. The yield of K-Na vaporized crystalline salt was 18.56%, in which the mass fractions of KCl, NaCl, CaSO4 and K2SO4 were about 61.21%, 13.40%, 14.62%and 10.86%, respectively. The leaching kinetics of potassium salt from the sintering dust fits the external diffusion model well. The leaching speed and the leaching rate of the potassium salt can be increased by increasing the leaching temperature, strengthening the stirring speed and increasing the liquid-solid ratio.展开更多
Several physical and chemical detection methods were used to study the basic properties of sintering dust (ESP dust) collected from Baogang Steel Corporation. The result shows that the major constituents of the ESP ...Several physical and chemical detection methods were used to study the basic properties of sintering dust (ESP dust) collected from Baogang Steel Corporation. The result shows that the major constituents of the ESP dust are KCl, NaCl, Fe2O_3 and Fe3O_4. Water leaching experiment on the sintering dust shows that KCl in the ESP dust can be separated and recovered by water leaching and fractional crystallization. Component analysis of leaching solution indicates that the massive calcium sulfate in the leaching solution should be removed first in order to obtain the pure potassium salt. In order to provide theoretical guidance to inhibit the dissolution of calcium ions from the sintering dust, the water leaching experiment of ESP dust and the dissolution behavior of CaSO_4 in the potassium chloride, sodium chloride, potassium sulfate and their mixed salt solution were studied. It is found that, a lower liquid-solid ratio should be chosen in the leaching process to inhibit the dissolution of calcium sulfate dehydrate. Using sodium carbonate solution as a precipitating agent, the influences of the concentration of sodium carbonate solution, reaction temperature, stirring speed and equilibrium time on the preparation of the spherical calcium carbonate were studied. Spherical calcium carbonate with good dispersing performance and grain size distribution in nanometer range of less than 10 μm was obtained. Furthermore, a potassium recovery process with joint production of spherical calcium carbonate was designed. This process is technically viable and considerable in economic benefit.展开更多
Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution...Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution by radical polymerization. New polymer drilling fluids are made up of HPAP, which is used as viscosifiers and encapsulation agents. Properties of this system are reported in this paper. Results indicate that this system has a high value of yield point to plastic viscosity (YP/PV≥0.7), high viscosity at a low-shear rate (LSRV≥30000mPa·s), excellent shear thinning behavior, good solid-carrying behavior, resistance to shear, good thermal stability (as high as 140℃) and salt resistance. The system has excellent behavior in high-density solution of NaCl and in calcium and magnesium rich saline solutions. Hence, HPAP also can be used in saltwater polymer drilling fluids.展开更多
Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldsp...Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldspar as the principal mineral enriched in potassium could be decomposed in the media of Ca(OH)_2, NaOH, KOH-H_2O solution via hydrothermal treatment, into tobermorite, hydroxylcancrinite, and kalsilite respectively. By further processing, these compounds are feasible for being as slow-release carrier of potassium nitrate, extracting alumina, and preparing farm-oriented fertilizers of potassium sulphate and nitrate. Correspondingly, the filtrate is KOH,(Na, K)_2SiO_3, and K_2SiO_3 solution, from which potassium carbonate, sulphate, nitrate, and phosphate could be easily fabricated. As NaO H and KOH are recycled in the processing chains by causticizing sodium and/or potassium metasilicate solutions, the hydrothermal alkaline techniques as developed in this research have several advantages as lower consumption of disposable mineral resources and energy, maximized utilization of potassic mineral resources, as well as clean productions etc. Based on the approaches presented in this paper, the technical system of efficiently utilizing insoluble potassium resources has been established. The hydrothermal alkaline methods are feasible to be industrialized on a large scale, thus resulting in decreasing imports of potash fertilizers, improving the pattern of potassium fertilizer consumption, and enhancing the supplying guarantee of potassium resource in China.展开更多
Analyzes on solid potassium mineral reserves calculation methods and existing problems of chaerhan salt lake,t with many parameters comparison solid potassium mineral reserves calculation results are reliable,the
A greenhouse study was conducted to explore the effect of various rates of potassium sulfate (K2SO4) nanoparticles on alfalfa (Medicago sativa L.) growth and physiological response under salt stress. One salt-tolerant...A greenhouse study was conducted to explore the effect of various rates of potassium sulfate (K2SO4) nanoparticles on alfalfa (Medicago sativa L.) growth and physiological response under salt stress. One salt-tolerant genotype (Mesa-Sirsa) and one salt-sensitive genotype (Bulldog 505) were selected based on germination under salt and were planted in pots containing 2 kg of sand. The two genotypes were subjected to 0 and 6 dS·m-1 salt levels using CaCl2·2H2O: NaCl (2:1) mixed with Hoagland solution. Three K2SO4 nanoparticle treatments consisting of, 1/4, 1/8, and 1/10 of the potassium (K) level in full strength Hoagland solution (235 mg·L-1) were applied. Adding K2SO4 nanoparticles at the 1/8 level resulted in the highest shoot dry weight, relative yield, root length and root dry weight in both genotypes. The different rates of K2SO4 nanoparticles affected significantly Na/K ratio and the concentrations of Calcium (Ca), Phosphorus (P), Copper (Cu), Manganese (Mn), and Zinc (Zn) in plant tissue. The application of K2SO4 nanoparticles at the 1/8 rate enhanced the plant’s physiological response to salt stress by reducing electrolyte leakage, increasing catalase and proline content, and increasing antioxidant enzymes, activity. These results suggest that the application of K nanoparticles may have better efficiency than conventional K fertilizers in providing adequate plant nutrition and overcoming the negative effects of salt stress in alfalfa.展开更多
1 Introduction Salt Lake,as a kind of chemical resources,has been attracted to many researchers,especially the resources of lithium.As reported,many kinds of brines exist in the world depending on the compositions of ...1 Introduction Salt Lake,as a kind of chemical resources,has been attracted to many researchers,especially the resources of lithium.As reported,many kinds of brines exist in the world depending on the compositions of the brine.Based on the chemical composition the brines can be classified as the types of chloride,carbonate,sulfate.For different展开更多
Atmospheric particle pollution is one of the major factors leading to degradation of ancient wall paintings,particularly heritage sites in arid and semi-arid regions.However,current systematic research on the changes,...Atmospheric particle pollution is one of the major factors leading to degradation of ancient wall paintings,particularly heritage sites in arid and semi-arid regions.However,current systematic research on the changes,sources,and influential factors of atmospheric particulate matter and its water-soluble ion concentrations is not sufficient.Thus,the major water-soluble ion concentrations,sources,and influential factors of atmospheric particles PM_(2.5) and PM_(10)(particulate matter with an aerodynamic equivalent diameter≤2.5 and 10.0μm,respectively,in ambient air)were collected from Cave 16 and its ambient exterior environment in the Dunhuang Mogao Grottoes,China,between April 2015 and March 2016.Results showed that the concentrations of PM_(2.5) and PM_(10) inside and outside the cave were the highest in March 2016 and the lowest in December 2015.The higher particle concentration from March to May was related to the frequent occurrence of sand and dust events,and the lower particle concentration from June to September was associated with good diffusion conditions,increased precipitation,and an established cave shelterbelt.The concentration of particulate matter inside the cave was affected by the concentration of particles in the air outside the cave.Ca2+,NH+4,Na+,Cl-,and SO2-4were the main components of the total ions of PM_(2.5) and PM_(10) both inside and outside the cave.The total ions inside the cave were frequently affected by the disturbance of tourists'activities during the peak tourist season from May to August.Under the influence of dust,the total concentrations of Cl-,SO2-4,Na+,NH+4,and Ca2+in particles of different sizes inside and outside the cave increased,and the concentrations of Cl-,SO2-4,Na+,and Ca2+decreased during precipitation period.Backward air mass trajectory analysis suggested that the pollutants were mainly from Xinjiang,China.The pollutant sources of air particulates are straw burning,secondary pollution sources,soil dust,dry spring rivers,and tourist activities.展开更多
Background: Food plays an important role in human health. A healthy diet contributes to the improvement of the health of populations. A diet high in sodium/salt and low in potassium has been shown to contribute to car...Background: Food plays an important role in human health. A healthy diet contributes to the improvement of the health of populations. A diet high in sodium/salt and low in potassium has been shown to contribute to cardiovascular disease. The objective of this study was to assess the knowledge, attitudes and practices (KAP) of the inhabitants of Dapaong and its surroundings on dietary intakes of sodium/salt and potassium. Methods: This was a cross-sectional study conducted from 1 November to 15 December 2022 involving 400 adults aged 25 to 44 years. Sampling was done using the probability method and the multistage random sampling technique with proportional allocation. These two methods were applied to select villages, households, and primary targets in each locality according to whether the area of residence was urban or rural. The electronic kobocollect questionnaire was administered to people in households and the interview guide was to resource persons, administrators and community leaders to collect the data. Results: Overall, 80.25% of the respondents had low knowledge of sodium/salt intakes;88.50% had poor attitudes towards the use of foods that provide more sodium/salt and 92.75% had behaviours that were not conducive to reducing excessive salt consumption. With regard to potassium, the same trend was observed in the order of 91%, 72% and 73.75%. Conclusion: The KAP levels of the people studied were not good. The populations are prone to cardiovascular disease. A multisectoral nutritional intervention would be essential to improve the knowledge of the populations on sodium/salt and potassium intakes and therefore favourable to the fight against CVD/NCD.展开更多
Permian salt-bearing formation covers a substantial area of the Russian Plate.In some places,it is up to several kilometers thick.The salt-bearing formation contains unique accumulations of potassium and magnesium salts,
Objective Large-conductance calcium-activated potassium(BKCa)channel modulates vascular smooth muscle tone.In the present study,we tested the hypothesis that salt,one of the factors which significantly influence blood...Objective Large-conductance calcium-activated potassium(BKCa)channel modulates vascular smooth muscle tone.In the present study,we tested the hypothesis that salt,one of the factors which significantly influence blood pressure(BP),can regulate BKCa activity and then elevate blood pressure.Methods Male Sprague-Dawley rats aged 6 weeks were randomized into high salt diet group(HS)and control group,fed with high salt diet(containing 5% NaCl)and standard rat chow(containing 0.4% NaCl)respectively for 16 weeks.Tail systolic blood pressure(SBP),body weight(BW)and 24-hour urinary output were tested every 4 weeks.Content of urinary Na+ was detected using flame spectrophotometrical method.At the end of 16 weeks,all the rats were killed,the mesenteric arteries were obtained,and single mesenteric smooth muscle cells were isolated at once.The resting membrane potential(Em),the total potassium currents and the currents after perfusion with TEA solution of the cells were all recorded by whole cell patch clamp.The transcriptions of BKCa channel α and β1 subunits in mesenteric arterial vascular smooth muscle cells(VSMC)of each group were calculated by real-time RT-PCR.Results There was no difference in SBP and BW at each stage between control group and HS group;the urinary Na+ level in HS animals was elevated significantly after 4 weeks.The negative values of Em in HS group VSMCs were reduced compared with those in the control group.Transcriptions of β1 subunit of BKCa channels were decreased in HS group,but α subunit transcriptions did not differ between the two groups.Whole cell potassium currents did not differ between HS and control groups,but BKCa currents of HS group VSMCs were lower than those of control group ones.Conclusion Even without elevating SBP,salt-loading can still modulate the expression and activity of BKCa channel in the mesenteric arterial VSMC and elevate vascular tone.展开更多
In order to study the effects of nitrogen fertilizer application methods and nitrogen fertilizer regulation with straw-return on wheat yield and potassium forms in the soil, field experiment was arranged in Pinyuan Co...In order to study the effects of nitrogen fertilizer application methods and nitrogen fertilizer regulation with straw-return on wheat yield and potassium forms in the soil, field experiment was arranged in Pinyuan County, and the effects of the regulation of different ratios of basal to topdressed nitrogen on the yield of wheat and the contents of different forms of potassium in the soil were studied. The re- sults indicated that in the condition of straw-return, the yield of wheat was the high- est after the treatments of the ratios of basal to topdressed nitrogen of 7:3 and 6:4. As to the contents of different forms of potassium, the contents of water-soluble potassium, exchangeable potassium and total potassium treated by the ratios of basal to topdressed nitrogen of 7:3 and 6:4 were the highest, and the differences of non-exchangeable potassium among all treatments were not significant. Under the experiment condition, the ratios of basal to topdressed nitrogen of 7:3 and 6:4 were the best treatments, they can increase the wheat yield and the contents of available potassium and total potassium in the soil.展开更多
The kinetics of potassium intercalating into graphite in molten KF at 1 163 K was investigated by means of cyclic voltammetry and chronoamperometry.Cyclic voltammetry results indicate that intercalaltion/deintercalati...The kinetics of potassium intercalating into graphite in molten KF at 1 163 K was investigated by means of cyclic voltammetry and chronoamperometry.Cyclic voltammetry results indicate that intercalaltion/deintercalation of potassium into/from graphite involve kinetic limitations.The intercalation process of potassium was further confirmed to be governed by both the diffusion of potassium ion in graphite bulk and the phase transition kinetics through the analyses of current-time transient curves with reversible and quasi-reversible equations.The transfer coefficient of the intercalation reaction was calculated to be 0.364 according to the parameters resulting from nonlinear fitting of the current-time transient curves with a quasi-reversible equation.Analysis with scanning electron microscope shows that graphite matrix was severely eroded by intercalation of potassium.展开更多
This paper briefly introduces resources characteristics and development advantages for Charhan salt lake;and elaborated the technology progress to increase potassium mining scale systematically,the impact of the
Potassium and phosphate were extracted at low temperature by acid hydrolysis process to decompose a new type of associated phosphorus and potassium ore. The main factors affecting the dissolution rate were investigate...Potassium and phosphate were extracted at low temperature by acid hydrolysis process to decompose a new type of associated phosphorus and potassium ore. The main factors affecting the dissolution rate were investigated, such as grinding fineness, the amount of sulfuric acid and fluoride salt, reaction time and temperature, etc. Meanwhile, the effects of various factors on the formation of soluble potassium and phosphate were also discussed. The reaction products and residues were determined by X-ray diffraction(XRD), scanning electron microscopic(SEM) analysis and other means. The results showed that the dissolution rates of potassium and phosphorus were 70wt% and 93.7wt%, respectively, under the conditions of a grain size of 95.64wt% lessthan 0.074 mm, 9.78 g·g^(-1) sulfuric acid, 0.5 g·g^(-1) ammonium fluoride, 160 ℃ and a reaction time of 2h. The thermodynamic and chemical reaction mechanism was revealed that the primary reaction could be completed spontaneously in a temperature range of 298-433 K. The increase of reaction temperature had an important influence on ion exchange reaction, which was more conducive to the spontaneous process. The research will open up a new way for efficient use of potassium ore resources.展开更多
The yeast HAL1 gene was introduced into Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation with vacuum infiltration under the control of CaMV 35S promoter. Thirty-three individual kanamycin resi...The yeast HAL1 gene was introduced into Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation with vacuum infiltration under the control of CaMV 35S promoter. Thirty-three individual kanamycin resistant plants were obtained from 75,000 seeds. Southern blotting analysis indicated that HAL1 gene had been integrated into all of the transgenic plants’ genomes. The copy number of HAL1 gene in transgenic plants was mostly 1 to 3 by Southern analysis. Phenotypes of transgenic plants have no differences with wild type plants. several samples of transformants were self-pollinated, and progenies from transformed and non-transformed plants (controls) were evaluated for salt tolerance and gene expression. Measurement of concentrations of intracellular K+ and Na+ showed that transgenic lines were able to retain less Na+ than that of the control under salt stress. Results from different tests indicated the expression of HAL1 gene promotes a higher level of salt tolerance in vivo in the transgenic Arabidopsis plants.展开更多
A novel method, i.e. molten salt method, was adopted to prepare potassium sodium titanate nanotubes. EDX results indicated that the ion-exchange reaction reached an equilibrium state at around 9 h. The 24 h ion-exchan...A novel method, i.e. molten salt method, was adopted to prepare potassium sodium titanate nanotubes. EDX results indicated that the ion-exchange reaction reached an equilibrium state at around 9 h. The 24 h ion-exchanged product maintained nano-tubular and its crystalline structure was consistent with that of Na2Ti2O4(OH)2 nanotubes. The nanotubes have a high specific surface area, possibly making this material a good candidate as controlled release materials, catalyst, electrode materials, etc..展开更多
The cycling performance, impedance variation, and cathode surface evolution of the Li/LiCoO2 cell using Li FSI–KFSI molten salt electrolyte are reported. It is found that this battery shows poor cycling performance, ...The cycling performance, impedance variation, and cathode surface evolution of the Li/LiCoO2 cell using Li FSI–KFSI molten salt electrolyte are reported. It is found that this battery shows poor cycling performance, with capacity retention of only about 67% after 20 cycles. It is essential to understand the origin of the instability. It is noticed that the polarization voltage and the impedance of the cell both increase slowly upon cycling. The structure and the properties of the pristine and the cycled LiCoO2 cathodes are investigated by x-ray diffraction(XRD), scanning electron microscopy(SEM), Raman spectroscopy, x-ray photoelectron spectroscopy(XPS), and transmission electron microscopy(TEM). It is found that the LiCoO2 particles are corroded by this molten salt electrolyte, and the decomposition by-product covers the surface of the LiCoO2 cathode after 20 cycles. Therefore, the surface side reaction explains the instability of the molten salt electrolyte with LiCoO2.展开更多
Salinity is a major impediment to crop production. This study was undertaken to compare the effect of seaweed extract, humic acid, and potassium sulfate nanoparticles in alleviating salt stress in Alfalfa (Medicago sa...Salinity is a major impediment to crop production. This study was undertaken to compare the effect of seaweed extract, humic acid, and potassium sulfate nanoparticles in alleviating salt stress in Alfalfa (Medicago sativa L.). Seeds of ten alfalfa genotypes were germinated in a growth chamber at five salt concentrations (0%, 0.5%, 1.0%, 1.5%, and 2.00%). Salt concentrations above 1% reduced seed germination by more than 70% in most genotypes. One salt tolerant genotype (Mesa-Sirsa) and one salt sensitive (Bulldog 505) were selected and planted in greenhouse pots containing 2 kg of sand and subjected to two salt levels (10 and 15 dS· m-1). Four treatments consisting of 1) control (Hoagland solution, no-salt), 2) seaweed extract at 4 Kg·ha-1, 3) humic acid at 28 L· ha-1, and 4) potassium sulfate at 300 Kg· ha-1. Plant biomass was reduced under both salt concentrations in both genotypes, with a greater magnitude in the salt sensitive genotype. Application of seaweed extract resulted in higher relative water content and proline under both salt concentrations (10 and 15 dS·m-1) in the salt sensitive genotype, and lower electrolyte leakage in both salt tolerant and salt sensitive genotypes, under both salt concentrations. Seaweed extract also resulted in higher catalase and SOD activities in both genotypes under 10 dS·m-1. Catalase and SOD activities were associated with significantly (p < 0.01) reduced electrolyte leakage and increased shoot dry weight. Overall, seaweed extract seemed to have a positive effect in alleviating salt stress in alfalfa.展开更多
Background: The Togolese population, like those around the world, frequently consumes foods high in salt/sodium and low in potassium, thus exposing them to cardiovascular disease (CVD). Nutritional intervention can he...Background: The Togolese population, like those around the world, frequently consumes foods high in salt/sodium and low in potassium, thus exposing them to cardiovascular disease (CVD). Nutritional intervention can help reverse this consumption pattern and reduce related CVD morbidity and mortality. The objective of this study was to measure the effects of a nutrition education intervention on the consumption frequencies of foods rich in sodium and potassium. Methods: The study was a quasi-experimental before- and-after study, conducted from 08 January to 16 April 2023. It involved 200 adults aged 25 - 64 years, randomly selected from two areas: an intervention area and a non-intervention area. Data were collected in two phases at 3-month intervals in both groups. The intervention consisted of nutrition education (awareness raising and cooking demonstrations) on reducing salt/sodium intake and increasing potassium-rich food intake. The kobocollect electronic questionnaire was administered to the respondents to collect data on the frequency of consumption of foods rich in sodium and potassium. Results: The median age of the respondents was 33 years old (30;38) and 56% of the participants were women, 44% and 69% respectively in the control and intervention groups. Most participants lived in rural areas (51%), 52.4% and 49.5% in the control and intervention groups respectively. Overall, 4% (p individuals reduced their frequency of adding salt at mealtime from more than 3 times a week to less than 3 times, i.e., 5.6% in the intervention group and 1.7% in the control group. The proportion of individuals who consumed meals with green leafy vegetable sauces was reduced from more than 3 times a week to less than 3 times, i.e., 7.5% (p < 0.022), or 1% in the intervention group and 4% in the control group. Education level (0.23 [0.10 - 0.50];p - 6.35];p < 0.0006) were associated with reduced salt addition at meals. The same trend was observed for increased consumption of green leafy vegetable sauces (0.95 [0.03 - 0.99];p male (2 [1.08 - 1.84];p Conclusion: This study was able to measure the effects of a nutrition education intervention for adequate sodium and potassium intakes on changing favourable dietary behaviour through a quasi-experimental study. The results show that the continuation of the intervention will contribute to the adoption of favourable behaviours for the reduction of dietary sodium intakes and the optimisation of potassium intakes.展开更多
基金Projects (2012AA062502,2012AA06A118) supported by the High-tech Research and Development Program of China
文摘Surface morphology and inner structure of the dust were observed by ICP-AES, SEM-EDS and XRD to examine the strengthening measures of leaching potassium salt from the sintering dust by water. The results showed that the main component of the sintering dust was iron-oxygen compound, with KCl adsorbed on its surface. Leaching experiments showed that the KCl in the ESP dust could be separated and recovered by water leaching and fractional crystallization. The yield of K-Na vaporized crystalline salt was 18.56%, in which the mass fractions of KCl, NaCl, CaSO4 and K2SO4 were about 61.21%, 13.40%, 14.62%and 10.86%, respectively. The leaching kinetics of potassium salt from the sintering dust fits the external diffusion model well. The leaching speed and the leaching rate of the potassium salt can be increased by increasing the leaching temperature, strengthening the stirring speed and increasing the liquid-solid ratio.
基金Projects(2012AA062502,2012AA06A118)supported by the National High-tech Research and Development Program of China
文摘Several physical and chemical detection methods were used to study the basic properties of sintering dust (ESP dust) collected from Baogang Steel Corporation. The result shows that the major constituents of the ESP dust are KCl, NaCl, Fe2O_3 and Fe3O_4. Water leaching experiment on the sintering dust shows that KCl in the ESP dust can be separated and recovered by water leaching and fractional crystallization. Component analysis of leaching solution indicates that the massive calcium sulfate in the leaching solution should be removed first in order to obtain the pure potassium salt. In order to provide theoretical guidance to inhibit the dissolution of calcium ions from the sintering dust, the water leaching experiment of ESP dust and the dissolution behavior of CaSO_4 in the potassium chloride, sodium chloride, potassium sulfate and their mixed salt solution were studied. It is found that, a lower liquid-solid ratio should be chosen in the leaching process to inhibit the dissolution of calcium sulfate dehydrate. Using sodium carbonate solution as a precipitating agent, the influences of the concentration of sodium carbonate solution, reaction temperature, stirring speed and equilibrium time on the preparation of the spherical calcium carbonate were studied. Spherical calcium carbonate with good dispersing performance and grain size distribution in nanometer range of less than 10 μm was obtained. Furthermore, a potassium recovery process with joint production of spherical calcium carbonate was designed. This process is technically viable and considerable in economic benefit.
文摘Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution by radical polymerization. New polymer drilling fluids are made up of HPAP, which is used as viscosifiers and encapsulation agents. Properties of this system are reported in this paper. Results indicate that this system has a high value of yield point to plastic viscosity (YP/PV≥0.7), high viscosity at a low-shear rate (LSRV≥30000mPa·s), excellent shear thinning behavior, good solid-carrying behavior, resistance to shear, good thermal stability (as high as 140℃) and salt resistance. The system has excellent behavior in high-density solution of NaCl and in calcium and magnesium rich saline solutions. Hence, HPAP also can be used in saltwater polymer drilling fluids.
基金granted by China Geological Survey Project(12120113087700)Fundamental Research Funds for the Central Universities(2652014017)+10 种基金the National Eleventh Five-year Supporting Plan for Science and Technology(2006BAD10B04)Specialized Research Funds for Doctoral Program of Higher Education(1999049114)supported by the Provincial Science and Technology Programs of Henan(0524250042)Inner Mongolia(20020307)Shanxi(001065)Beijing(953500400)enterprises of Shaanxi Daqin Potassium Industry CorporationTongling Chemical Industry Group CorporationShanxi Ziguang Potassium Industry CorporationHenan Qianhe Mining Corporationthe Geological Survey of Tianjin
文摘Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldspar as the principal mineral enriched in potassium could be decomposed in the media of Ca(OH)_2, NaOH, KOH-H_2O solution via hydrothermal treatment, into tobermorite, hydroxylcancrinite, and kalsilite respectively. By further processing, these compounds are feasible for being as slow-release carrier of potassium nitrate, extracting alumina, and preparing farm-oriented fertilizers of potassium sulphate and nitrate. Correspondingly, the filtrate is KOH,(Na, K)_2SiO_3, and K_2SiO_3 solution, from which potassium carbonate, sulphate, nitrate, and phosphate could be easily fabricated. As NaO H and KOH are recycled in the processing chains by causticizing sodium and/or potassium metasilicate solutions, the hydrothermal alkaline techniques as developed in this research have several advantages as lower consumption of disposable mineral resources and energy, maximized utilization of potassic mineral resources, as well as clean productions etc. Based on the approaches presented in this paper, the technical system of efficiently utilizing insoluble potassium resources has been established. The hydrothermal alkaline methods are feasible to be industrialized on a large scale, thus resulting in decreasing imports of potash fertilizers, improving the pattern of potassium fertilizer consumption, and enhancing the supplying guarantee of potassium resource in China.
文摘Analyzes on solid potassium mineral reserves calculation methods and existing problems of chaerhan salt lake,t with many parameters comparison solid potassium mineral reserves calculation results are reliable,the
文摘A greenhouse study was conducted to explore the effect of various rates of potassium sulfate (K2SO4) nanoparticles on alfalfa (Medicago sativa L.) growth and physiological response under salt stress. One salt-tolerant genotype (Mesa-Sirsa) and one salt-sensitive genotype (Bulldog 505) were selected based on germination under salt and were planted in pots containing 2 kg of sand. The two genotypes were subjected to 0 and 6 dS·m-1 salt levels using CaCl2·2H2O: NaCl (2:1) mixed with Hoagland solution. Three K2SO4 nanoparticle treatments consisting of, 1/4, 1/8, and 1/10 of the potassium (K) level in full strength Hoagland solution (235 mg·L-1) were applied. Adding K2SO4 nanoparticles at the 1/8 level resulted in the highest shoot dry weight, relative yield, root length and root dry weight in both genotypes. The different rates of K2SO4 nanoparticles affected significantly Na/K ratio and the concentrations of Calcium (Ca), Phosphorus (P), Copper (Cu), Manganese (Mn), and Zinc (Zn) in plant tissue. The application of K2SO4 nanoparticles at the 1/8 rate enhanced the plant’s physiological response to salt stress by reducing electrolyte leakage, increasing catalase and proline content, and increasing antioxidant enzymes, activity. These results suggest that the application of K nanoparticles may have better efficiency than conventional K fertilizers in providing adequate plant nutrition and overcoming the negative effects of salt stress in alfalfa.
文摘1 Introduction Salt Lake,as a kind of chemical resources,has been attracted to many researchers,especially the resources of lithium.As reported,many kinds of brines exist in the world depending on the compositions of the brine.Based on the chemical composition the brines can be classified as the types of chloride,carbonate,sulfate.For different
基金supported by the National Natural Science Foundation of China(51962001,32260292)the National Key Research&Development Projects(2020YFC1522200)the Gansu Provincial Science and Technology Plan Project(20JR5RA051,21YF1FF371).
文摘Atmospheric particle pollution is one of the major factors leading to degradation of ancient wall paintings,particularly heritage sites in arid and semi-arid regions.However,current systematic research on the changes,sources,and influential factors of atmospheric particulate matter and its water-soluble ion concentrations is not sufficient.Thus,the major water-soluble ion concentrations,sources,and influential factors of atmospheric particles PM_(2.5) and PM_(10)(particulate matter with an aerodynamic equivalent diameter≤2.5 and 10.0μm,respectively,in ambient air)were collected from Cave 16 and its ambient exterior environment in the Dunhuang Mogao Grottoes,China,between April 2015 and March 2016.Results showed that the concentrations of PM_(2.5) and PM_(10) inside and outside the cave were the highest in March 2016 and the lowest in December 2015.The higher particle concentration from March to May was related to the frequent occurrence of sand and dust events,and the lower particle concentration from June to September was associated with good diffusion conditions,increased precipitation,and an established cave shelterbelt.The concentration of particulate matter inside the cave was affected by the concentration of particles in the air outside the cave.Ca2+,NH+4,Na+,Cl-,and SO2-4were the main components of the total ions of PM_(2.5) and PM_(10) both inside and outside the cave.The total ions inside the cave were frequently affected by the disturbance of tourists'activities during the peak tourist season from May to August.Under the influence of dust,the total concentrations of Cl-,SO2-4,Na+,NH+4,and Ca2+in particles of different sizes inside and outside the cave increased,and the concentrations of Cl-,SO2-4,Na+,and Ca2+decreased during precipitation period.Backward air mass trajectory analysis suggested that the pollutants were mainly from Xinjiang,China.The pollutant sources of air particulates are straw burning,secondary pollution sources,soil dust,dry spring rivers,and tourist activities.
文摘Background: Food plays an important role in human health. A healthy diet contributes to the improvement of the health of populations. A diet high in sodium/salt and low in potassium has been shown to contribute to cardiovascular disease. The objective of this study was to assess the knowledge, attitudes and practices (KAP) of the inhabitants of Dapaong and its surroundings on dietary intakes of sodium/salt and potassium. Methods: This was a cross-sectional study conducted from 1 November to 15 December 2022 involving 400 adults aged 25 to 44 years. Sampling was done using the probability method and the multistage random sampling technique with proportional allocation. These two methods were applied to select villages, households, and primary targets in each locality according to whether the area of residence was urban or rural. The electronic kobocollect questionnaire was administered to people in households and the interview guide was to resource persons, administrators and community leaders to collect the data. Results: Overall, 80.25% of the respondents had low knowledge of sodium/salt intakes;88.50% had poor attitudes towards the use of foods that provide more sodium/salt and 92.75% had behaviours that were not conducive to reducing excessive salt consumption. With regard to potassium, the same trend was observed in the order of 91%, 72% and 73.75%. Conclusion: The KAP levels of the people studied were not good. The populations are prone to cardiovascular disease. A multisectoral nutritional intervention would be essential to improve the knowledge of the populations on sodium/salt and potassium intakes and therefore favourable to the fight against CVD/NCD.
文摘Permian salt-bearing formation covers a substantial area of the Russian Plate.In some places,it is up to several kilometers thick.The salt-bearing formation contains unique accumulations of potassium and magnesium salts,
文摘Objective Large-conductance calcium-activated potassium(BKCa)channel modulates vascular smooth muscle tone.In the present study,we tested the hypothesis that salt,one of the factors which significantly influence blood pressure(BP),can regulate BKCa activity and then elevate blood pressure.Methods Male Sprague-Dawley rats aged 6 weeks were randomized into high salt diet group(HS)and control group,fed with high salt diet(containing 5% NaCl)and standard rat chow(containing 0.4% NaCl)respectively for 16 weeks.Tail systolic blood pressure(SBP),body weight(BW)and 24-hour urinary output were tested every 4 weeks.Content of urinary Na+ was detected using flame spectrophotometrical method.At the end of 16 weeks,all the rats were killed,the mesenteric arteries were obtained,and single mesenteric smooth muscle cells were isolated at once.The resting membrane potential(Em),the total potassium currents and the currents after perfusion with TEA solution of the cells were all recorded by whole cell patch clamp.The transcriptions of BKCa channel α and β1 subunits in mesenteric arterial vascular smooth muscle cells(VSMC)of each group were calculated by real-time RT-PCR.Results There was no difference in SBP and BW at each stage between control group and HS group;the urinary Na+ level in HS animals was elevated significantly after 4 weeks.The negative values of Em in HS group VSMCs were reduced compared with those in the control group.Transcriptions of β1 subunit of BKCa channels were decreased in HS group,but α subunit transcriptions did not differ between the two groups.Whole cell potassium currents did not differ between HS and control groups,but BKCa currents of HS group VSMCs were lower than those of control group ones.Conclusion Even without elevating SBP,salt-loading can still modulate the expression and activity of BKCa channel in the mesenteric arterial VSMC and elevate vascular tone.
基金Supported by the Project of National Science and Technology Support Plan-"Integration and Demonstration ration of Straw Resources Recycling Technologies in Huang-HuaiHai Plain Area"(2012BAD14B07)the Project of Major Application Technology Innovation of Agriculture in Shandong Province-"Study on Recycling Technology of Waste Resourcization in Large-scale Farm"+1 种基金the Foundation for Outstanding Young Scientist in Shandong Province-"Study on the Mechanism of the Effect of Drip Irrigation with Saline Water on Soil Environment and Its Crop Response"(BS2011NY017)the Project of National Natural Science Foundation-"Study on the Allocation Pattern and Interface Control of Salinity under the Condition of Brackish Water Irrigation"(51209130)~~
文摘In order to study the effects of nitrogen fertilizer application methods and nitrogen fertilizer regulation with straw-return on wheat yield and potassium forms in the soil, field experiment was arranged in Pinyuan County, and the effects of the regulation of different ratios of basal to topdressed nitrogen on the yield of wheat and the contents of different forms of potassium in the soil were studied. The re- sults indicated that in the condition of straw-return, the yield of wheat was the high- est after the treatments of the ratios of basal to topdressed nitrogen of 7:3 and 6:4. As to the contents of different forms of potassium, the contents of water-soluble potassium, exchangeable potassium and total potassium treated by the ratios of basal to topdressed nitrogen of 7:3 and 6:4 were the highest, and the differences of non-exchangeable potassium among all treatments were not significant. Under the experiment condition, the ratios of basal to topdressed nitrogen of 7:3 and 6:4 were the best treatments, they can increase the wheat yield and the contents of available potassium and total potassium in the soil.
基金Project(1343-74236000004)supported by the Hunan Province Innovation Foundation for Postgraduate
文摘The kinetics of potassium intercalating into graphite in molten KF at 1 163 K was investigated by means of cyclic voltammetry and chronoamperometry.Cyclic voltammetry results indicate that intercalaltion/deintercalation of potassium into/from graphite involve kinetic limitations.The intercalation process of potassium was further confirmed to be governed by both the diffusion of potassium ion in graphite bulk and the phase transition kinetics through the analyses of current-time transient curves with reversible and quasi-reversible equations.The transfer coefficient of the intercalation reaction was calculated to be 0.364 according to the parameters resulting from nonlinear fitting of the current-time transient curves with a quasi-reversible equation.Analysis with scanning electron microscope shows that graphite matrix was severely eroded by intercalation of potassium.
文摘This paper briefly introduces resources characteristics and development advantages for Charhan salt lake;and elaborated the technology progress to increase potassium mining scale systematically,the impact of the
基金Funded by the National Natural Science Fundation of China(51274158)the National Twelfth Five-Year Plan for Scientific and Technological Support(2013BAE04B03)the Scientific and Technological Support Project of Hubei Province(2015BCA251)
文摘Potassium and phosphate were extracted at low temperature by acid hydrolysis process to decompose a new type of associated phosphorus and potassium ore. The main factors affecting the dissolution rate were investigated, such as grinding fineness, the amount of sulfuric acid and fluoride salt, reaction time and temperature, etc. Meanwhile, the effects of various factors on the formation of soluble potassium and phosphate were also discussed. The reaction products and residues were determined by X-ray diffraction(XRD), scanning electron microscopic(SEM) analysis and other means. The results showed that the dissolution rates of potassium and phosphorus were 70wt% and 93.7wt%, respectively, under the conditions of a grain size of 95.64wt% lessthan 0.074 mm, 9.78 g·g^(-1) sulfuric acid, 0.5 g·g^(-1) ammonium fluoride, 160 ℃ and a reaction time of 2h. The thermodynamic and chemical reaction mechanism was revealed that the primary reaction could be completed spontaneously in a temperature range of 298-433 K. The increase of reaction temperature had an important influence on ion exchange reaction, which was more conducive to the spontaneous process. The research will open up a new way for efficient use of potassium ore resources.
基金a grant from State 863 National High Technology Research Development Project of China, No. 819-0803.
文摘The yeast HAL1 gene was introduced into Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation with vacuum infiltration under the control of CaMV 35S promoter. Thirty-three individual kanamycin resistant plants were obtained from 75,000 seeds. Southern blotting analysis indicated that HAL1 gene had been integrated into all of the transgenic plants’ genomes. The copy number of HAL1 gene in transgenic plants was mostly 1 to 3 by Southern analysis. Phenotypes of transgenic plants have no differences with wild type plants. several samples of transformants were self-pollinated, and progenies from transformed and non-transformed plants (controls) were evaluated for salt tolerance and gene expression. Measurement of concentrations of intracellular K+ and Na+ showed that transgenic lines were able to retain less Na+ than that of the control under salt stress. Results from different tests indicated the expression of HAL1 gene promotes a higher level of salt tolerance in vivo in the transgenic Arabidopsis plants.
基金supported by the National Natural Science Foundation of China(No.20071010).
文摘A novel method, i.e. molten salt method, was adopted to prepare potassium sodium titanate nanotubes. EDX results indicated that the ion-exchange reaction reached an equilibrium state at around 9 h. The 24 h ion-exchanged product maintained nano-tubular and its crystalline structure was consistent with that of Na2Ti2O4(OH)2 nanotubes. The nanotubes have a high specific surface area, possibly making this material a good candidate as controlled release materials, catalyst, electrode materials, etc..
基金Project supported by the Beijing S&T Project,China(Grant No.Z13111000340000)the National Basic Research Program of China(Grant No.2012CB932900)the National Natural Science Foundation of China(Grants Nos.51325206 and 51421002)
文摘The cycling performance, impedance variation, and cathode surface evolution of the Li/LiCoO2 cell using Li FSI–KFSI molten salt electrolyte are reported. It is found that this battery shows poor cycling performance, with capacity retention of only about 67% after 20 cycles. It is essential to understand the origin of the instability. It is noticed that the polarization voltage and the impedance of the cell both increase slowly upon cycling. The structure and the properties of the pristine and the cycled LiCoO2 cathodes are investigated by x-ray diffraction(XRD), scanning electron microscopy(SEM), Raman spectroscopy, x-ray photoelectron spectroscopy(XPS), and transmission electron microscopy(TEM). It is found that the LiCoO2 particles are corroded by this molten salt electrolyte, and the decomposition by-product covers the surface of the LiCoO2 cathode after 20 cycles. Therefore, the surface side reaction explains the instability of the molten salt electrolyte with LiCoO2.
文摘Salinity is a major impediment to crop production. This study was undertaken to compare the effect of seaweed extract, humic acid, and potassium sulfate nanoparticles in alleviating salt stress in Alfalfa (Medicago sativa L.). Seeds of ten alfalfa genotypes were germinated in a growth chamber at five salt concentrations (0%, 0.5%, 1.0%, 1.5%, and 2.00%). Salt concentrations above 1% reduced seed germination by more than 70% in most genotypes. One salt tolerant genotype (Mesa-Sirsa) and one salt sensitive (Bulldog 505) were selected and planted in greenhouse pots containing 2 kg of sand and subjected to two salt levels (10 and 15 dS· m-1). Four treatments consisting of 1) control (Hoagland solution, no-salt), 2) seaweed extract at 4 Kg·ha-1, 3) humic acid at 28 L· ha-1, and 4) potassium sulfate at 300 Kg· ha-1. Plant biomass was reduced under both salt concentrations in both genotypes, with a greater magnitude in the salt sensitive genotype. Application of seaweed extract resulted in higher relative water content and proline under both salt concentrations (10 and 15 dS·m-1) in the salt sensitive genotype, and lower electrolyte leakage in both salt tolerant and salt sensitive genotypes, under both salt concentrations. Seaweed extract also resulted in higher catalase and SOD activities in both genotypes under 10 dS·m-1. Catalase and SOD activities were associated with significantly (p < 0.01) reduced electrolyte leakage and increased shoot dry weight. Overall, seaweed extract seemed to have a positive effect in alleviating salt stress in alfalfa.
文摘Background: The Togolese population, like those around the world, frequently consumes foods high in salt/sodium and low in potassium, thus exposing them to cardiovascular disease (CVD). Nutritional intervention can help reverse this consumption pattern and reduce related CVD morbidity and mortality. The objective of this study was to measure the effects of a nutrition education intervention on the consumption frequencies of foods rich in sodium and potassium. Methods: The study was a quasi-experimental before- and-after study, conducted from 08 January to 16 April 2023. It involved 200 adults aged 25 - 64 years, randomly selected from two areas: an intervention area and a non-intervention area. Data were collected in two phases at 3-month intervals in both groups. The intervention consisted of nutrition education (awareness raising and cooking demonstrations) on reducing salt/sodium intake and increasing potassium-rich food intake. The kobocollect electronic questionnaire was administered to the respondents to collect data on the frequency of consumption of foods rich in sodium and potassium. Results: The median age of the respondents was 33 years old (30;38) and 56% of the participants were women, 44% and 69% respectively in the control and intervention groups. Most participants lived in rural areas (51%), 52.4% and 49.5% in the control and intervention groups respectively. Overall, 4% (p individuals reduced their frequency of adding salt at mealtime from more than 3 times a week to less than 3 times, i.e., 5.6% in the intervention group and 1.7% in the control group. The proportion of individuals who consumed meals with green leafy vegetable sauces was reduced from more than 3 times a week to less than 3 times, i.e., 7.5% (p < 0.022), or 1% in the intervention group and 4% in the control group. Education level (0.23 [0.10 - 0.50];p - 6.35];p < 0.0006) were associated with reduced salt addition at meals. The same trend was observed for increased consumption of green leafy vegetable sauces (0.95 [0.03 - 0.99];p male (2 [1.08 - 1.84];p Conclusion: This study was able to measure the effects of a nutrition education intervention for adequate sodium and potassium intakes on changing favourable dietary behaviour through a quasi-experimental study. The results show that the continuation of the intervention will contribute to the adoption of favourable behaviours for the reduction of dietary sodium intakes and the optimisation of potassium intakes.