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Delving into the dissimilarities in electrochemical performance and underlying mechanisms for sodium and potassium ion storage in N-doped carbon-encapsulated metallic Cu_(2)Se nanocubes
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作者 Xinyu Wang Yanan Xu +4 位作者 Xiaofeng Liu Lei Tan Huaiqiang Gu Xin Du Dan Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期336-347,I0008,共13页
The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical perfo... The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical performance.Herein,metallic Cu_(2)Se encapsulated with N-doped carbon(Cu_(2)Se@NC)was prepared using Cu_(2)O nanocubes as templates through a combination of dopamine polymerization and hightemperature selenization.The unique nanocubic structure and uniform N-doped carbon coating could shorten the ion transport distance,accelerate electron/charge diffusion,and suppress volume variation,ultimately ensuring Cu_(2)Se@NC with excellent electrochemical performance in sodium ion batteries(SIBs)and potassium ion batteries(PIBs).The composite exhibited excellent rate performance(187.7 mA h g^(-1)at 50 A g^(-1)in SIBs and 179.4 mA h g^(-1)at 5 A g^(-1)in PIBs)and cyclic stability(246,8 mA h g^(-1)at 10 A g^(-1)in SIBs over 2500 cycles).The reaction mechanism of intercalation combined with conversion in both SIBs and PIBs was disclosed by in situ X-ray diffraction(XRD)and ex situ transmission electron microscope(TEM).In particular,the final products in PIBs of K_(2)Se and K_(2)Se_(3)species were determined after discharging,which is different from that in SIBs with the final species of Na_(2)Se.The density functional theory calculation showed that carbon induces strong coupling and charge interactions with Cu_(2)Se,leading to the introduction of built-in electric field on heterojunction to improve electron mobility.Significantly,the theoretical calculations discovered that the underlying cause for the relatively superior rate capability in SIBs to that in PIBs is the agile Na~+diffusion with low energy barrier and moderate adsorption energy.These findings offer theoretical support for in-depth understanding of the performance differences of Cu-based materials in different ion storage systems. 展开更多
关键词 Cu_(2)Se nanocubes DFT calculations Ion storage mechanism potassium ion batteries sodium ion batteries
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Measurement of the Effects of Nutritional Education for Reducing Sodium Intakes and Increasing Potassium Intakes
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作者 Tchasso Serge Kénao Jerôme Charles Sossa +6 位作者 Moussiliou Noel Paraiso Smaila Alidou Ghislain Sopoh Toyi Tchamdja Dadja Essoya Landoh Mofou Bélo Tchaa Abalo Bakaï 《Food and Nutrition Sciences》 CAS 2023年第5期436-450,共15页
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
关键词 Nutrition Education Consumption Frequency sodium/Salt potassium TOGO
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Knowledge, Attitudes and Practices of the Populations of Dapaong and Its Surroundings in Togo on Sodium/Salt and Potassium Intakes
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作者 Tchasso Serge Kenao Jerôme Charles Sossa +7 位作者 Moussiliou Noel Paraiso Mofou Belo Mouawiyatou Bouraima Ghislain Sopoh Smaila Alidou Dadja Essoya Landoh Assima-Essodom Kalao Victoire Agueh 《Open Journal of Epidemiology》 2023年第2期113-127,共15页
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
关键词 KAP sodium/Salt potassium TOGO
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Analgesic effect of intrathecal bumetanide is accompanied by changes in spinal sodium-potassium-chloride co-transporter 1 and potassium-chloride co-transporter 2 expression in a rat model of incisional pain 被引量:2
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作者 Yanbing He Shiyuan Xu +1 位作者 Junjie Huang Qingjuan Gong 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第10期1055-1062,共8页
Accumulating evidence has demonstrated that the sodium-potassium-chloride co-transporter 1 and potassium-chloride co-transporter 2 have a role in the modulation of pain transmission at the spinal level through chlorid... Accumulating evidence has demonstrated that the sodium-potassium-chloride co-transporter 1 and potassium-chloride co-transporter 2 have a role in the modulation of pain transmission at the spinal level through chloride regulation in the pain pathway and by effecting neuronal excitability and pain sensitization. The present study aimed to investigate the analgesic effect of the speciifc sodium-potassium-chloride co-transporter 1 inhibitor bumetanide, and the change in spinal sodium-potassium-chloride co-transporter 1 and potassium-chloride co-transporter 2 expression in a rat model of incisional pain. Results showed that intrathecal bumetanide could decrease cumulative pain scores, and could increase thermal and mechanical pain thresholds in a rat model of incisional pain. Sodium-potassium-chloride co-transporter 1 expression in-creased in neurons from dorsal root ganglion and the deep laminae of the ipsilateral dorsal horn following incision. By contrast, potassium-chloride co-transporter 2 expression decreased in neurons of the deep laminae from the ipsilateral dorsal horn. These ifndings suggest that spinal sodium-potassium-chloride co-transporter 1 expression was up-regulated and spinal potassi-um-chloride co-transporter 2 expression was down-regulated following incision. Intrathecal bumetanide has analgesic effects on incisional pain through inhibition of sodium-potassi-um-chloride co-transporter 1. 展开更多
关键词 nerve regeneration sodium-potassium-chloride co-transporter 1 potassium-chloride co-transporter 2 BUMETANIDE spinal cord dorsal root ganglion incision model postoperative pain neural regeneration
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Sodium and potassium in the bones of penguin and skua revealed by EPR and SR-XRF technique
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作者 谢周清 徐思琦 +3 位作者 黄宇营 何伟 金嗣昭 孙立广 《Chinese Journal of Polar Science》 2010年第1期22-30,共9页
Penguin and skua in the maritime Antarctic have high salt loadings in the body due to almost exclusive diet consumption of marine invertebrates.However,the storage and turnover of sodium and potassium in these animals... Penguin and skua in the maritime Antarctic have high salt loadings in the body due to almost exclusive diet consumption of marine invertebrates.However,the storage and turnover of sodium and potassium in these animals are poorly investigated.Here we determined the concentration and microscopic distribution of the two elements in the bones of penguin and skua.The average concentrations of sodium and potassium in penguin bone were comparable with that in skua bone(0.18% and 0.82% for penguin bone;0.19% and 0.76% for skua bone in dry weight).The ratios of sodium to calcium and potassium to calcium(0.0330 and 0.0075 for penguin,0.0335 and 0.0082 for skua in average by weight) were somewhat higher than the reported ratios for terrestrial animals,indicating these marine animals' bone enrichment of salt.The ratios of sodium to potassium in average by weight were 6.75 and 4.65 for penguin and skua,respectively.This value is much lower compared with the bulk sea water ratio of about 27.0,implying that potassium is favorable to reside in the bone rather than sodium.Both sodium and potassium were found to significant correlation with the content of organic materials in bone based upon the intensity of native signal determined by electron paramagnetic resonance(EPR).It was estimated that almost all of potassium is kept within the organic phases,while about 30% of sodium is stored in organic phases and the other 70% within mineral phase.The microscopic distributions of potassium in the cross-section and/or surface were revealed by synchrotron radiation Xray fluorescence(SR-XRF) technique.The ratio of potassium to calcium based upon the SR-XRF intensity counter varied considerably from the surface to the interior,and on the surface the highest concentration of potassium was observed in the middle section with decreasing amounts toward the edge.This indirectly documented that exchange of potassium between fluid and bone organic phase maybe occur. 展开更多
关键词 bone penguin and skua sodium and potassium electron paramagnetic resonance(EPR) synchrotron radiation X-ray fluorescence(SR-XRF).
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The Effect of Water and Salt Stress on Paspalum dilatatum,a Constituent of Pampas Natural Grasslands
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作者 Claudia A.Porcelli Gerardo Rubio +1 位作者 Flavio H.Gutiérrez Boem Raul S.Lavado 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第8期2009-2018,共10页
The effects of the salt stress on plant growth are usually increased by the water stress.We studied the impact of both stresses in simultaneous pulses of drought and salinity on Paspalum dilatatum.This forage species ... The effects of the salt stress on plant growth are usually increased by the water stress.We studied the impact of both stresses in simultaneous pulses of drought and salinity on Paspalum dilatatum.This forage species is native to South America,spread in grasslands in many tropical,subtropical,and temperate areas of the world,and very common in grasslands of the Flooding Pampas of Argentina.Mimicking what happens in nature.We compared a pot experiment,a non-stressed control against water stress for a month(midpoint between field capacity and wilting point),and two saline stresses(moderate,6 d·Sm^(−1)and strong,12 d·Sm^(−1)),also for a month.Aerial biomass(green leaf;non-leaf green material,and dry material)and roots were harvested,weighed,and analyzed for nitrogen,phosphorus,and cations.The biomass of all components significantly decreased when both stresses were applied.Water plus strong saline stress reduced by half the total biomasses,compared to the control.The proportion of aerial biomass/root biomass ratio as well as aerial green component/dry materials ratio tend to decrease when subjected to both stresses.Nitrogen concentration in plants was not significantly affected,but phosphorus concentration increased in aerial biomass components,from 0.10 to 0.18 mg·kg^(−1)between the extreme treatments,but did not change in roots.Sodium concentration in plants increased(i.e.,in green leave sodium(Na)increased from 0.27 to 2.01 mg·kg^(−1)between the extreme treatments),whereas other cations either did not change or decreased,affecting the ratios between them.Sodium performance allows us to infer that the Na accumulation of P.dilatatum behaves in an intermediate range,compared to very tolerant to salts or non-salt tolerant species of the Paspalum genus.In agreement,when salts were applied in the form of a pulse,P.dilatatum tolerated higher salinity than that found by other authors for the same species,using continuous salinity. 展开更多
关键词 Dallis grass SALINITY drought sodium in plants phosphorus in plants potassium/sodium ratio
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Nucleotide Contribution to the Functioning of SERT, Na /K ATPase and GPCR Proteins
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作者 Wynford Robert Williams 《Journal of Biosciences and Medicines》 2024年第5期61-76,共16页
Purine nucleotides are crucial for the effective operation of cell membrane proteins maintaining the neurotransmitter responses of 5-HT. Major protein targets in the treatment of depression include SERT, N/K ATPase an... Purine nucleotides are crucial for the effective operation of cell membrane proteins maintaining the neurotransmitter responses of 5-HT. Major protein targets in the treatment of depression include SERT, N/K ATPase and GPCR. Each protein target is responsive to a specific complement of drugs: antidepressants (SERT), lithium and cardiogenic steroids (N/K ATPase), 5-HT receptor ligands (GPCR). Computational software is useful for comparing molecular similarity within ligand-ligand and ligand-nucleotide structures. Previous studies demonstrate that GPCR ligands of different pharmacologic classes display relative molecular similarity to nucleotide structures. The current study applies this methodology to compound structures modulating SERT and N/K ATPase receptors. Minimum energy conformers of SERT antagonists demonstrate relative molecular similarity to the structural template of GTP nucleotide. GTP template fits of 5-HT and psilocin are similar, whereas a SERT-like fit is one of several for the ketamine structure. Endogenous and pharmaceutical modulators of Na/K ATPase relate to adenine nucleotide. The fits of cardiogenic steroids to a cGMP template demonstrate similarities and differences between compounds. Relative molecular similarity within the structures of hormones, drugs and nucleotides has implications for neurotransmitter transport and cell signal transduction processes. 展开更多
关键词 SERT SSRI GPCR sodium/potassium ATPase NUCLEOTIDES Depression
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Adsorption of Potassium and Sodium Ions by Variable Charge Soils 被引量:4
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作者 LIHONG-YAN JIGUO-LIANG 《Pedosphere》 SCIE CAS CSCD 1992年第3期245-254,共10页
Adsorption of potassium and sodium ions by four typical variable charge soils of South China was studied. The results indicated that the variable charge soils saturated with H and Al showed a much higher preference fo... Adsorption of potassium and sodium ions by four typical variable charge soils of South China was studied. The results indicated that the variable charge soils saturated with H and Al showed a much higher preference for potassium ions relative to sodium ions, and this tendency could not be changed by such factors as the pH, the concentration of the cations, the dielectric constant of solvent, the accompanying anions and the iron oxide content etc., suggesting that this difference in affinity is caused by the difference in the nature of the two cations. It was observed that a negative adsorption of sodium ions by latosol and lateritic red soil in a mixed system containing equal amount of potassium and sodium ions at low pH, which is caused by a competitive adsorption of potassium and sodium ions and repulsion of positive charge on the surfaces of soil particles for cations. The adsorption of potassium and sodium ions increased with the decreases in the dielectric constant of solvent and the iron oxide content. Sulfate affected the adsorption of potassium and sodium ions through changing the surface properties of the soils. 展开更多
关键词 ADSORPTION potassium ions sodium ions variable charge soils
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First-principles study of the local structure and crystal field of Yb^(2+) in sodium and potassium halides
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作者 闻军 段昌奎 +3 位作者 尹民 Yu.V.Orlovskii 夏上达 章永凡 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期349-354,共6页
The local coordination structures around the doping Yb2+ ions in sodium and potassium halides were calculated by using the first-principles supercell model. Both the cases with and without the charge compensation vac... The local coordination structures around the doping Yb2+ ions in sodium and potassium halides were calculated by using the first-principles supercell model. Both the cases with and without the charge compensation vacancy in the local environment of the doping Yb2+ were calculated to study the effect of the doping on the local coordination structures of Yb2+. Using the calculated local structures, we obtained the crystal-field parameters for the Yb2+ ions doped in sodium and potassium halides by a method based on the combination of the quantum-chemical calculations and the effective Hamiltonian method. The calculated crystal-field parameters were analyzed and compared with the fitted results. 展开更多
关键词 sodium and potassium halides local coordination structure DISTORTION crystal-field parameters
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Separation of potassium from sodium in alkaline solution by solvent extraction with 4-tert-butyl-2-(α-methylbenzyl)phenol
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作者 XING Peng WANG Cheng-yan +1 位作者 CHEN Yong-qiang MA Bao-zhong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第7期2003-2009,共7页
This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-B... This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-BAMBP)than 4-sec-butyl-2-(α-methylbenzyl)phenol(BAMBP).The optimum conditions for the extraction were 1 mol/L t-BAMBP,3:1 volumetric phase ratio(O/A),and two extraction stages.After cross-current extraction,the extraction ratio of potassium reached 90.8%.After scrubbing with deionised water at phase ratio of 4:1 and scrubbing stage of 4,a sodium scrubbing efficiency of 88.2%was obtained.After stripping using 1 mol/L H_(2)SO_(4) at phase ratio of 3:1,the stripping efficiency of potassium reached 94.2%.The potassium/sodium(K/Na)concentration ratio increased 14.3 times from 0.15 in the feed solution to 2.3 in the stripping solution.The efficient separation of potassium from sodium in alkaline solution was achieved via solvent extraction with t-BAMBP. 展开更多
关键词 4-tert-butyl-2-(α-methylbenzyl)phenol(t-BAMBP) potassium sodium solvent extraction separation
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Effect of interferon + Potassium Sodium Dehydroandrograpolide Succinate therapy on inflammatory response and immune response in children with hand-foot-mouth disease
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作者 Dong-Lin Li Yi Yan 《Journal of Hainan Medical University》 2018年第15期65-68,共4页
Objective: To investigate the effect of interferon + Potassium Sodium Dehydroandrograpolide Succinate therapy on inflammatory response and immune response in children with hand-foot-mouth disease. Methods: A total of ... Objective: To investigate the effect of interferon + Potassium Sodium Dehydroandrograpolide Succinate therapy on inflammatory response and immune response in children with hand-foot-mouth disease. Methods: A total of 116 children with hand-foot-mouth disease who were treated in this hospital between September 2016 and February 2018 were selected as the study subjects and divided into the control group (n=58) and the Potassium Sodium Dehydroandrograpolide Succinate group (n=58) by random number table method. Control group received symptomatic + interferon therapy, and Potassium Sodium Dehydroandrograpolide Succinate group received symptomatic + interferon + Potassium Sodium Dehydroandrograpolide Succinate therapy, and they were treated for 1 week. The differences in the serum contents of inflammatory factors, adhesion molecules and humoral immunity indexes were compared between the two groups before and after treatment. Results:Before treatment, serum levels of inflammatory factors, adhesion molecules and humoral immunity indexes were not significantly different between the two groups. After 1 week of treatment, serum inflammatory factors IL-1β, IL-10, PCT and hs-CRP levels of Potassium Sodium Dehydroandrograpolide Succinate group were lower than those of control group;serum adhesion molecules CD44, ICAM-1 and VCAM-1 levels were lower than those of control group;serum humoral immunity indexes IgA, IgG, C3 and C4 levels were lower than those of control group. Conclusion: Interferon + Potassium Sodium Dehydroandrograpolide Succinate therapy can effectively reduce the systemic inflammatory response and improve the humoral immune function in children with hand-foot-mouth disease. 展开更多
关键词 Hand-foot-mouth disease INTERFERON potassium sodium Dehydroandrograpolide SUCCINATE Inflammatory RESPONSE immune RESPONSE
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Effect of Interaction of Potassium, Calcium and Sodium on Cabbage Growth and Nutrient Absorption 被引量:1
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作者 李明悦 廉晓娟 +4 位作者 宁晓光 高伟 赵秋 朱静华 高贤彪 《Agricultural Science & Technology》 CAS 2013年第7期1008-1010,1025,共4页
ObjectiveThis study aimed to investigate the effect of the interactions among potassium (K), calcium (Ca) and sodium (Na) on cabbage growth and nutrient absorption. MethodA total of 11 treatments with different ... ObjectiveThis study aimed to investigate the effect of the interactions among potassium (K), calcium (Ca) and sodium (Na) on cabbage growth and nutrient absorption. MethodA total of 11 treatments with different levels of K, Ca and Na were set in the pot experiment to measure the nutrient content and uptake in cabbage plants. ResultThe use of K or the combined use of K and Ca improved the cabbage absorption on K and Ca. In addition, K and Ca presented an interaction as that appropriate amount of Ca promoted K uptake while excessive Ca inhibited the uptake. The treatment of Ca 2 K 3 with 0.33 g/pot of Ca and 0.67 g/pot of K could significantly increase the quantity of dry matter accumulation and absorption of Ca and K in cabbage, was the best among all treatments. ConclusionApplication of suitable amount of Ca could release the Na stress on cabbage growth at the low level of Na in soil. 展开更多
关键词 potassium CALCIUM sodium Vegetable growth Nutrient absorption
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Effects of Paper Mill Sludge on Potassium, Sodium, Calcium, and Magnesium Concentrations in Different Soybean Cultivars 被引量:13
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作者 YANXiang-Kui K.W.CHANG H.L.XU 《Pedosphere》 SCIE CAS CSCD 2005年第1期84-94,共11页
A field experiment was conducted on a sandy loam soil at an Experimental Farm in Taejon, South Korea, to determine the effects of paper mill sludge compost application rates on K, Na, Ca and Mg concentrations of soybe... A field experiment was conducted on a sandy loam soil at an Experimental Farm in Taejon, South Korea, to determine the effects of paper mill sludge compost application rates on K, Na, Ca and Mg concentrations of soybean (Glycine max (L.) Merr.) aboveground tissues and the genotypic effects on the concentrations of these elements. Sludge compost treatments of 0, 75, and 150 t ha-1 were applied to 30 diverse soybean cultivars. Concentrations of K, Na, Ca, and Mg in aboveground tissues harvested 69 days after … 展开更多
关键词 CALCIUM MAGNESIUM paper mill sludge potassium sodium SOYBEAN
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Baeyer-Villiger oxidation of cyclic ketones utilizing potassium peroxydisulfate(K_2S_2O_8) or sodium perborate(NaBO_3) in acidic media 被引量:8
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作者 S.Zarrabi N.O.Mahmoodi +1 位作者 K.Tabatabaeian M.A.Zanjanchi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1400-1404,共5页
The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfa... The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environmental procedure for industrial purposes than use of organic peracids. 展开更多
关键词 Baeyer-Villiger oxidation Cyclic ketones potassium peroxydisulfate (K2S208) Acidic media sodium perborate (NaBO3)
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Associations between serum potassium and sodium levels and risk of hypertension: a community-based cohort study 被引量:4
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作者 Lu XI Yong-Chen HAO Jing LIU Wei WANG Miao WANG Guo-Qi LI Yue QI Fan ZHAO Wu-Xiang XIE Yan LI Jia-Yi SUN Jun LIU Lan-Ping QIN Dong ZHAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2015年第2期119-126,共8页
Objective Several studies have examined the relationships between dietary potassium and sodium and hypertension, but few have evaluated the association between serum potassium or sodium and risk of incident hypertensi... Objective Several studies have examined the relationships between dietary potassium and sodium and hypertension, but few have evaluated the association between serum potassium or sodium and risk of incident hypertension. We therefore investigated the associations between serum potassium and sodium and risk of incident hypertension in a Chinese community-based population. Methods A total of 839 normotensive individuals without cardiovascular disease from the Chinese Multi-Provincial Cohort Study who took part in the baseline examination in 2007-2008 and the follow-up survey in 2012-2013 were included in this study. Odds ratios (OR) and 95% confidence intervals (95%CI) for baseline serum potassium and sodium in relation to the risk of new-onset hypertension were evaluated using multivari- ate logistic regression models. Results During five years of follow-up, 218 (26.0%) individuals progressed to hypertension. Logistic re- gression adjusting for multiple confounders showed that every 1 mEq/L increment in baseline serum potassium level was associated with a 75% increased risk of hypertension (OR: 1.75; 95%CI: 1.01-3.04; P = 0.04). Compared with adults with serum potassium level of 4.20-4.79 mEq/L, adults with level 〉 4.80 mEq/L had an 84% increased risk of hypertension (OR: 1.84; 95%CI: 1.14-2.96; P = 0.01). There was no significant association between serum sodium and risk of hypertension (OR: 0.96; 95%CI: 0.89-1.04; P = 0.33). Conclusions Base- line serum potassium level, but not baseline serum sodium level, was positively related to the risk of incident hypertension in the Chinese population. 展开更多
关键词 HYPERTENSION potassium SERUM sodium
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Conductivity Prediction of Sodium and Potassium Hydrogen Tartrates in Aqueous Solution at Low Concentration 被引量:2
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作者 倪良 蒋文华 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第2期159-162,共4页
An ionic conductivity prediction equation at low concentration for two acid salts is proposed taking into account the dissociation and association equilibria among ions. The salts considered are sodium and potassium h... An ionic conductivity prediction equation at low concentration for two acid salts is proposed taking into account the dissociation and association equilibria among ions. The salts considered are sodium and potassium hydrogen tartrates. There is no additional parameter of high order terms except for the Onsager's coefficient of limited term in the new equation. Results show a complex conductance of acidic tartrates in aqueous solution. The molar conductivities of metal ions are nearly constant such that the contributions from hydrogen and tartrate ions decrease with concentration, while the molar conductivity of bitartrate ion increases with concentration. 展开更多
关键词 sodium hydrogen tartrate potassium hydrogen tartrate prediction equation molar conductivity
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Effects of Phorbol-12,13-dibuterate on Sodium Currents and Potassium Currents in Rat Trigeminal Ganglion Neurons 被引量:1
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作者 刘慧 胡本容 +2 位作者 付晖 向继洲 刘烈炬 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第1期1-4,共4页
The effects of phorbol-12,13-dibuterate (PDBu) on total sodium current (INa-total), tetrodotoxin-resistant sodium current (INa-TFXr), 4-AP-sensitive potassium current (IA) and TEA-sensitive potassium current ... The effects of phorbol-12,13-dibuterate (PDBu) on total sodium current (INa-total), tetrodotoxin-resistant sodium current (INa-TFXr), 4-AP-sensitive potassium current (IA) and TEA-sensitive potassium current (IK) in trigeminal ganglion (TG) neurons were investigated. Whole-cell patch clamp techniques were used to record ion currents in cultured TG neurons of rats. Results revealed that 0.5μmol/L PDBu reduced the amplitude of INa-total by (38.3±4.5)% (n=6, P〈0.05), but neither the G-V curve (control: V0.5 =-17.1±4.3 mV, k=7.4±1.3; PDBu: V0.5=-15.9±5.9 mV, k=5.9±1.4; n=6, P〉0.05) nor the inactivation rate constant (control: 3.6±0.9 ms; PDBu: 3.6±0.8 ms; n=6, P〉0.05) was altered. 0.5 μmol/L PDBu could significantly increase the amplitude of INa-TFXr by (37.2± 3.2)% (n=9, P〈0.05) without affecting the G-V curve (control: V0.5=-14.7±6.0 mV, k=6.9± 1.4; PDBu: V0.5=- 11.1±5.3 mV, k=8.1± 1.5; n=5, P〉0.05 ) or the inactivation rate constant (control: 4.6±0.6 ms; PDBu: 4.2±0.5 ms; n=5, P〉0.05). 0.5 μmol/L PDBu inhibited IK by (15.6±5.0) % (n=16, P〈0.05), and V0.5 was significantly altered from - 4.7±1.4 mV to -7.9 ±1.8 mV (n=16, P〈0.05). IA was not significantly affected by PDBu, 0.5μmol/L PDBu decreased IA by only (0.3±3.2)% (n=5, P〉0.05). It was concluded that PDBu inhibited INa-total :.but enhanced INa-TFXr, and inhibited IK without affecting IA. These data suggested that the activation of PKC pathway could exert the actions. 展开更多
关键词 Phorbol-12 13-dibuterate trigeminal ganglion neurons sodium channel potassium channel
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Direct Determination of Potassium-Sodium Activity Ratio in Soil Suspension with Two Ion-Selective Electrodes 被引量:1
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作者 LIHONG-YAN JIGUO-LIANG 《Pedosphere》 SCIE CAS CSCD 1991年第4期363-369,共7页
A K+-selective electrode and a Na+-selective electrode were used to construct a measuring cell without liquid-junction for the determination of the ion activity ratio of K+ to Na+ in soil suspensions. The measured cel... A K+-selective electrode and a Na+-selective electrode were used to construct a measuring cell without liquid-junction for the determination of the ion activity ratio of K+ to Na+ in soil suspensions. The measured cell potential was not affected by the total electrolyte concentration when the total cation concentration was 10-1-10-3 mol L-1 and the concentration ratio CK+ / CNa+. was 10:1 to 1:50. When the concentration ratios were equal to 1and the total electrolyte concentrations were 10-2 and 10-3 mol L-1, the ion activity ratio measurement would not be affected by pH in the pH range of 3.5 to 11.5 and 4.4 to 11 respectively. Ions other than H+ have no remarkable influence on the measurement. The ion activity ratio of K+ to Na+ measured directly in soil suspension agree well with those in centrifuged supernant solution. The relative deviation was within 4%. From the measured ion activity ratio, the difference of the bonding energies of K+ and Na+ ions was calculated. 展开更多
关键词 ion activity ratio ion-selective electrode potassium ion sodium ion
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Hormonal and epigenetic regulation of root responses to salinity stress
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作者 Ping Yun Cengiz Kaya Sergey Shabala 《The Crop Journal》 SCIE CSCD 2024年第5期1309-1320,共12页
Salinity stress is a major environmental stress affecting crop productivity,and its negative impact on global food security is only going to increase,due to current climate trends.Salinity tolerance was present in wil... Salinity stress is a major environmental stress affecting crop productivity,and its negative impact on global food security is only going to increase,due to current climate trends.Salinity tolerance was present in wild crop relatives but significantly weakened during domestication.Regaining it back requires a good understanding of molecular mechanisms and traits involved in control of plant ionic and ROS homeostasis.This review summarizes our current knowledge on the role of major plant hormones(auxin,cytokinins,abscisic acid,salicylic acid,and jasmonate)in plants adaptation to soil salinity.We firstly discuss the role of hormones in controlling root tropisms,root growth and architecture(primary root elongation,meristematic activity,lateral root development,and root hairs formation).Hormone-mediated control of uptake and sequestration of key inorganic ions(sodium,potassium,and calcium)is then discussed followed by regulation of cell redox balance and ROS signaling in salt-stressed roots.Finally,the role of epigenetic alterations such as DNA methylation and histone modifications in control of plant ion and ROS homeostasis and signaling is discussed.This data may help develop novel strategies for breeding and cultivating salt-tolerant crops and improving agricultural productivity in saline regions. 展开更多
关键词 PHYTOHORMONE Root development sodium potassium ROS signal
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Swelling Performance Studies of Acrylamide/Potassium 3-Sulfopropyl Methacrylate/Sodium Alginate/Bentonite Biohybrid Sorbent Hydrogels in Binary Mixtures of Water-Solvent 被引量:2
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作者 Erdener Karadag Z.Deniz Kasim Oztürk +2 位作者 Ö mer Baris Uzüm Semiha Kundakci 《Journal of Encapsulation and Adsorption Sciences》 2019年第1期35-61,共27页
In this study, it was to investigate the swelling performance of novel biohybrid composite hydrogel sorbents containing acrylamide/potassium 3-sulfopropyl methacrylate/sodium alginate/bentonite in water and binary mix... In this study, it was to investigate the swelling performance of novel biohybrid composite hydrogel sorbents containing acrylamide/potassium 3-sulfopropyl methacrylate/sodium alginate/bentonite in water and binary mixtures of water-solvent. Novel hydrogels were synthesized with free radical solution polymerization by using ammonium persulfate/N,N,N’,N’-tetramethylethylenediamine as redox initiating pair in presence of poly(ethylene glycol) diacrylate as crosslinker. Swelling experiments were performed in water and binary mixtures of water-solvent (acetone, methanol and tetrahydrofuran) at 25°C, gravimetrically. Some swelling and diffusion properties of the hydrogels were calculated and they were discussed for the biohybrid/hybrid hydrogel systems prepared under various formulations. It has been seen the lower equilibrium percentage swelling ratio values (62% - 124%) in all solvent compositions in comparison with the equilibrium percentage swelling ratio values in water (718% - 2055%). Consequently, the hydrogel systems developed in this study could serve as a potential device for water and water-solvent binary mixtures. 展开更多
关键词 Acrylamide/potassium 3-Sulfopropyl Methacrylate Biohybrid Hydrogel SWELLING sodium Alginate BENTONITE Water-Solvent Binary Mixtures
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