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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders
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作者 Qing Qiu Mengting Yang +2 位作者 Danfeng Gong Haiying Liang Tingting Chen 《Neural Regeneration Research》 SCIE CAS 2025年第5期1258-1276,共19页
The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central n... The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be used to treat these disorders. We concluded that there are few clinical drugs that can improve the pathology these diseases by acting on potassium or calcium ions. Although a few novel ion-channelspecific modulators have been discovered, meaningful therapies have largely not yet been realized. The lack of target-specific drugs, their requirement to cross the blood–brain barrier, and their exact underlying mechanisms all need further attention. This review aims to explain the urgent problems that need research progress and provide comprehensive information aiming to arouse the research community's interest in the development of ion channel-targeting drugs and the identification of new therapeutic targets for that can increase the cure rate of nervous system diseases and reduce the occurrence of adverse reactions in other systems. 展开更多
关键词 ASTROCYTES calcium channels central nervous system extracellular ion concentration MICROGLIA neurological disorders NEURONS potassium channels
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Effects of Plant Growth Regulator on Absorption,Circulation and Contents of Potassium in Flue-cured Tobacco 被引量:7
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作者 沈方科 韦忠 +3 位作者 王蕾 尹永强 潘炜玲 顾明华 《Agricultural Science & Technology》 CAS 2011年第12期1877-1880,1982,共5页
[Objective] This study was to investigate the effects of plant growth regulator on accumulation and circulation of potassium in flue-cured tobacco.[Methods] Hydroponics experiment was adopted to study the effects of p... [Objective] This study was to investigate the effects of plant growth regulator on accumulation and circulation of potassium in flue-cured tobacco.[Methods] Hydroponics experiment was adopted to study the effects of plant growth regulator(NAA,GA3,BR) on accumulation and circulation of potassium in flue-cured tobacco.[Results] The BR treatment increased the absorption of potassium,calcium and magnesium in flue-cured tobacco,reduced the potassium emission from the root,enhanced the accumulation and contents and promoted the circulation of potassium in the tobacco plants.There was no statistical difference between the NAA and GA3 treatment.And BR treatment was 0.52%,0.30%,0.28% higher than NAA treatment in enhancing potassium content in tobacco plants at 2,7,12 d after topping.In a word,the results showed that BR treatment was the most.[Conclusion] BR treatment could effectively enhance potassium content in tobacco plants after topping. 展开更多
关键词 Flue-cured tobacco Absorption of potassium potassium circulation Plant growth regulator
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Effects of Cadmium Pollution in Soil on Contents and Accumulation Amounts of Nitrogen,Phosphorus, Potassium and Cadmium Elements in Potato Tubers
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作者 邓禄军 夏锦慧 +2 位作者 张亚莉 雷尊国 卢扬 《Agricultural Science & Technology》 CAS 2013年第9期1280-1284,共5页
[Objective] This study aimed to investigate the effects of cadmium contamination in soil on contents and accumulation amounts of nitrogen, phosphorus, potassium and cadmium elements in potato tubers. [Method] Pot expe... [Objective] This study aimed to investigate the effects of cadmium contamination in soil on contents and accumulation amounts of nitrogen, phosphorus, potassium and cadmium elements in potato tubers. [Method] Pot experiment was conducted using potato variety ‘Favorita' as experimental material, to determine the contents and accumulation amounts of nitrogen, phosphorus, potassium and cadmium elements in potato tubers after treatment with different concentrations of cadmium. [Result] The results showed that different concentrations of cadmium had various effects on the contents and accumulation amounts of nitrogen, phosphorus,potassium and cadmium elements in potato tubers. Nitrogen content in potato tubers was reduced under low cadmium stress and increased under moderate and high cadmium stress. Nitrogen accumulation amount in potato tubers in various cadmium treatments was significantly lower than that in control group(P0.05); with the increase of cadmium concentration in soil, phosphorus content increased extremely significantly(P0.05); potassium content in potato tubers in various cadmium treatments was extremely significantly higher than that in control group(P0.01). Potassium accumulation amount in potato tubers under low cadmium stress reached the highest, which was reduced with the increasing level of cadmium contamination; both content and accumulation amount of cadmium in potato tubers had extremely significantly positive linear correlation with different cadmium concentrations in soil(P 0.01). [Conclusion] Under cadmium-contaminated conditions, the application level of nitrogen fertilizer is reduced, and the application level of phosphorus fertilizer maintains unchanged. Under low cadmium-contaminated conditions, the application level of potassium fertilizer increases. Severely cadmium-contaminated soil is not suitable for potato cultivation. 展开更多
关键词 POTATO CADMIUM content ACCUMULATION
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Analysis of F_1 Heterosis of Potassium Content on Self-bred High-potassium New Strains of Flue-cured Tobacco
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作者 钟军 朱崇文 +1 位作者 潘著 戴林建 《Agricultural Science & Technology》 CAS 2017年第9期1623-1627,共5页
F1 potassium heterosis of 8 flue-cured tobacco varieties and 6 self-bred high-potassium new strains were studied. The results showed that the F1 mean het- erosis of potassium content had differences between different ... F1 potassium heterosis of 8 flue-cured tobacco varieties and 6 self-bred high-potassium new strains were studied. The results showed that the F1 mean het- erosis of potassium content had differences between different parts of plants, showing B2F (8.45%)〉X2F (7.59%)〉C3F (5.64%); the F1 over-parent heterosis of potassium content of various parts was not obvious, showing X2F (0.05%)〉C3F (-0.43%) 〉B2F (-0.48%); the F, control heterosis of potassium content of different parts showed B2F (17.81%)〉X2F (4.06%)〉C3F (1.12%). The variance of GCA of potassium content in various parts of the 6 self-bred high-potassium new strains was significant or extremely significant, and all leaves of GK2 had greater GCA effect on potassium content; C3F and X2F of GK7 had good GCA effect on potassium con- tent, but GCA effect was bad in B2F; GK9 preformed well in B2F but badly in C3F. The variance of SCA in all combinations was extremely significant, and the good combinations included Duoye 87xGK7 (17.19%) in B2F, Duoye 87xGK2 (25.63%), ChangbohuangxGK5 (19.43%), Yunyan 87xGK7 (22.78%), and Yunyan 87xGK9 (24.38%) in C3F, Coker176xGK7 (19.87%), 101xGK9 (15.89%), Yunyan 85xGK9 (19.15%), and Yunyan 87xGK9 (20.74%) in X2F. 展开更多
关键词 Flue-cured tobacco High potassium HETEROSIS
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Sugar beet yield and industrial sugar contents improved by potassium fertilization under scarce and adequate moisture conditions 被引量:5
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作者 Muhammad Umair Mubarak Muhammad Zahir +1 位作者 Sagheer Ahmad Abdul Wakeel 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第11期2620-2626,共7页
Sugar beet(Beta vulgaris L.) is an industrial crop, grown worldwide for sugar production. In Pakistan, sugar is mostly extracted from sugarcane, soil and environmental conditions are equally favorable for sugar beet... Sugar beet(Beta vulgaris L.) is an industrial crop, grown worldwide for sugar production. In Pakistan, sugar is mostly extracted from sugarcane, soil and environmental conditions are equally favorable for sugar beet cultivation. Beet sugar contents are higher than sugarcane sugar contents, which can be further increased by potassium(K) fertilization. Total K concentration is higher in Pakistani soils developed from mica minerals, but it does not represent plant available K for sustainable plant growth. A pot experiment was conducted in the wire-house of Institute of Soil and Environmental Sciences at University of Agriculture Faisalabad, Pakistan. K treatments were the following: no K(K_0), K application at 148 kg ha^(–1)(K_1) and 296 kg ha^(–1)(K_2). Irrigation levels were used as water sufficient at 60% water holding capacity and water deficient at 40% water holding capacity. The growth, yield and beet quality data were analyzed statistically using LSD. The results revealed that increase in the level of K fertilization at water sufficient level significantly increased plant growth, beet yield and industrial beet sugar content. The response of K fertilization under water deficient condition was also similar, however overall sugar production was less than that in water sufficient conditions. It is concluded from this study that K application could be used not only to enhance plant growth and beet yield but also enhance beet sugar content both under water-deficient as well as water-sufficient conditions. 展开更多
关键词 potassium irrigation levels beet yields sugar contents
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A facile one-pot hydrothermal synthesis as an efficient method to modulate the potassium content of cryptomelane and its effects on the redox and catalytic properties 被引量:1
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作者 Huiyan Pan Xiaowei Chen +3 位作者 Oihane Sanz Miguel A.Cauquia Jose M.Rodriguez-Izquierdoa Juan J.Delgado 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第6期940-952,共13页
Cryptomelane has been widely applied as catalyst in oxidation reactions due to its excellent redox properties and low cost.Here,a novel one-pot hydrothermal synthesis using a potassium permanganate aqueous solution as... Cryptomelane has been widely applied as catalyst in oxidation reactions due to its excellent redox properties and low cost.Here,a novel one-pot hydrothermal synthesis using a potassium permanganate aqueous solution as precursor and ethanol as reducing agent has successfully been developed to obtain cryptomelane nano-oxides.This synthetic route makes it possible to control the amount of potassium incorporated into the structure of the cryptomelane by selecting the appropriate synthesis temperature and ethanol initial concentration.Taking advantage of this approach,the effect of potassium concentration on the structural stability and reducibility of the cryptomelane,which are poorly discussed in the literature,has been studied.We have observed that samples with low content of potassium(~11%)show high conversions of CO to CO2 especially at low temperatures.The lower activity of the samples with high K contents(~16%)can be ascribed to the beneficial effect of K on the structural stability of cryptomelane in detriment of labile oxygen on cryptomelane surface. 展开更多
关键词 CRYPTOMELANE PYROLUSITE Catalytic CO oxidation Hydrothermal synthesis potassium content
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Hyperspectral Inversion of Potassium Content in Apple Leaves Based on Vegetation Index 被引量:2
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作者 Xiaoyan Guo Xicun Zhu +4 位作者 Cheng Li Yu Wei Xinyang Yu Gengxing Zhao Houxing Sun 《Agricultural Sciences》 2017年第8期825-836,共12页
The aim of this study is to establish the estimation model of potassium content in apple leaves by using vegetation index. A total of 96 fresh apple leaves were collected from 24 orchards in Qixia County, Shandong Pro... The aim of this study is to establish the estimation model of potassium content in apple leaves by using vegetation index. A total of 96 fresh apple leaves were collected from 24 orchards in Qixia County, Shandong Province. The spectral reflectance of the leaves was measured by ASD FieldSpec4. The difference vegetation index (DVI), ratio vegetation index (RVI) and normalized vegetation index (NDVI) were used to make the contour map through Matlab platform, and the combination of high correlation wavelength was selected to establish the random forest (RF) regression model of potassium content. The hyperspectral reflectance increased with the increase of leaf potassium content. The correlation between DVI and the content of potassium is higher than NDVI and RVI. The optimal vegetation index was DVI (364,740), the correlation coefficient was 0.5355. The random forest regression model established with DVI selected vegetation index was the best. R2 was 0.8995, RMSE and RE% were 0.0791 and 0.0617 respectively. Using DVI to establish the random forest regression model to reverse the potassium content of apple leaves has achieved good results. It is important to determine the growth status of apple in hyperspectral and to determine the potash fertilizer of apple trees. 展开更多
关键词 HYPERSPECTRAL Inversion VEGETATION Index APPLE Tree LEAF potassium content Random Forest Regression Model
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Effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate 被引量:4
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作者 ZHANGJin LIGui-bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第3期342-345,共4页
Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics ... Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate were evaluated through different kinetics studies. Since chlorine was an electron withdrawing atom, the substitution of chlorine on the aromatic ring decreased the oxidation rate constant by σ-electron withdrawing conductive effect. The substitution of chlorine at ortho or para position on the aromatic ring increased the oxidation rate constant by π-electron donating conjugative effect, and the conjugative effect could counteract the negative impact of the conductive effect to some extent. On the other hand, the substitution of chlorine at ortho position on the aromatic ring decreased the oxidation rate constant by steric hindrance effect. The oxidation rate constants of phenol and chlorinated phenols studied decreased as follow order: 4-chlorophenol>2,4-dichlorophenol>phenol>2,6-dichlorophenol. 展开更多
关键词 oxidation KINETICS PHENOL 4-CHLOROPHENOL 2 4-DICHLOROPHENOL 2 6-DICHLOROPHENOL potassium permanganate
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Effect of operating conditions and potassium content on Fischer-Tropsch liquid products produced by potassium-promoted iron catalysts 被引量:1
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作者 Francisco E.M.Farias Fernando G.Sales Fabiano A.N.Fernandes 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期175-178,共4页
The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium mola... The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium molar content. The study followed an experimental planning and the results were analyzed based on surface response methodology. The effects of different operating conditions and potassium contents on the liquid product distribution were compared based on number average carbon number and dispersion. Results showed that high pressures (25 to 30 arm) favored the production of waxes that could be converted into liquid fuels through hydrocracking, while greater direct selectivity towards diesel was favored by low pressure (20 arm) using catalysts with low potassium to iron molar ratios. The liquid product distribution produced using an iron catalyst with high potassium content presented higher number-average number of carbons when compared to the distribution obtained using an iron catalyst with low potassium content. 展开更多
关键词 Fischer-Tropsch synthesis liquid fuels iron-based catalyst potassium
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Effects of Potassium Fertilizer on Water-Soluble Carbohydrate Content of Timothy (<i>Phleum pratense</i>L.), Silage Fermentation, Nutritive Values, and Nutrient Intake 被引量:1
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作者 Peng Wang Kousaku Souma +7 位作者 Hideki Okamoto Satomi Kin Akane Sugita Akihiro Furudate Chihiro Sato Akio Nibe Yimin Cai Takayoshi Masuko 《American Journal of Plant Sciences》 2014年第7期1030-1038,共9页
The objective of this study was to examine the effects of potassium fertilizer (standard (S) and high (H) levels) on water-soluble carbohydrate (WSC) content of timothy (Phleum pratense L.), silage fermentation, nutri... The objective of this study was to examine the effects of potassium fertilizer (standard (S) and high (H) levels) on water-soluble carbohydrate (WSC) content of timothy (Phleum pratense L.), silage fermentation, nutritive values, and nutrient intake. The silage treatments were as follows: S level without inoculant (SC), S level plus inoculant (SI), H level without inoculant (HC), and H level plus inoculant (HI). The K content was increased by 14.5% in timothy grown with the H level compared with the S level. The WSC contents of the S and H treatments were 75.9 and 66.1 g·kg-1 dry matter (DM), respectively. The silage fermentation quality was low with both SC and HC treatments. The addition of inoculant significantly improved the fermentation quality in SI and HI treatments. The addition increased the DM and organic matter digestibilities of silage. The total digestible nutrient (TDN) content of silage was highest with the HI treatment. The DM, TDN, and digestible energy intakes with the SI and HI treatments were improved compared with the SC and HC treatments, respectively. This study demonstrated negligible effects of K fertilizer levels and significant effects of the lactic acid bacteria inoculant on the fermentation quality, nutritive values, and feed intake of silage. 展开更多
关键词 Feed Intake Fermentation Quality Nutritive Value potassium Fertilizer TIMOTHY SILAGE
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Effect of Rhizobium Inoculation and Supplementation with Phosphorus and Potassium on Growth and Total Leaf Chlorophyll (Chl) Content of Bush Bean <i>Phaseolus vulgaris</i>, L. 被引量:2
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作者 Abdulkadir Mfilinge Kelvin Mtei Patrick Ndakidemi 《Agricultural Sciences》 2014年第14期1413-1426,共14页
The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in nort... The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in northern Tanzania. To achieve this aim, the glasshouse experiment was conducted at Nelson Mandela African Institution of Science and Technology while field experiment were carried out at Tanzania Coffee Research Institute, in Kilimanjaro, Tanzania between April-July 2014. The experiment was laid out in factorial arrangement. Factor I comprised of three bush bean varieties. Factor II involved two inoculation treatments viz 1) inoculation with Rhizobium spp. and 2) without inoculation. Factor III included four fertilizer levels (0 Kg·ha-1 20 Kg K ha-1, 30 Kg P ha-1 and 20 kg·K + 30 Kg P ha-1). Both screen house and field experiments were replicated four times. Plant growth parameters (plant height (cm), number leaves per plant, stem girth (mm)) were measured at 2, 4 and 6 weaks after planting (WAP). The chlorophyll was extracted by using Dimethylsulphoxide (DMSO) and absorbance was determined at 645 and 663nm using UV/Visible spectrophotometer. Results showed that Rhizobium application significantly improved the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content. Furthermore, compared with the zero treatment control, potassium fertilization significantly increased the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content of the three varieties. In general, these parameters were significantly increased with phosphorus supplied at 30 kg/ha. The combination of these supplies at different levels resulted in significant interactions in some parameters and thus indicating need for these inputs in the study area. 展开更多
关键词 Legumes Total LEAF CHLOROPHYLL content Photosynthesis Plant Height RHIZOBIA Stem Girth
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Optimization of Anti-Collapse Drilling Fluid Systems with High Potassium Content
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作者 Yu Xia Jian Guan +2 位作者 Yong Gao Shanfa Tang Jialuo Rong 《Fluid Dynamics & Materials Processing》 EI 2023年第6期1609-1622,共14页
The ash mudstone in some oil formations is highly water-sensitive.The oil formation is fractured,and the risk of well leakage and collapse is not negligible.This study presents a countermeasure for well collapse preve... The ash mudstone in some oil formations is highly water-sensitive.The oil formation is fractured,and the risk of well leakage and collapse is not negligible.This study presents a countermeasure for well collapse prevention,based on a“force-chemistry synergistic balance”approach and the utilization of environmentally friendly and efficient hydration inhibitors.The relevance of this approach is demonstrated considering a drilling fluid system with the high potassium content.The analysis shows that the system can maintain good rheological properties,filtration loss and suspension stability even after aging at 130℃ for 16 h.The primary roll recovery of rock chips is better than 98%.The secondary rolling recovery rate is 89%.The rapid water loss is close to zero.The effects of carrying rock,sand,hydration inhibition and dispersion of drill chips are all noticeable. 展开更多
关键词 Mudstone hydration force-chemistry synergistic balance environmental protection high potassium content potent inhibition anti-collapse drilling fluid
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Study of the Opuntia ficus indica and Its Radioactive Potassium Content using the Gamma Spectrometry 被引量:1
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作者 Guillermo Espmosa Jose-Ignaclo Golzarri Edgar Padilla-Soriano 《Journal of Environmental Science and Engineering(B)》 2016年第4期167-172,共6页
Mexico is one of the largest producers of nopal (Opuntiaficus indica). This "vegetable" is consumed on a daily basis by the Mexican population, being a source of food nutrients. Among its benefits, it is considere... Mexico is one of the largest producers of nopal (Opuntiaficus indica). This "vegetable" is consumed on a daily basis by the Mexican population, being a source of food nutrients. Among its benefits, it is considered the content of potassium, which is essential for human life and health. In this study, it analyzes the content of potassium of the Mexican cactus (Opuntiaficus indica) grown in 5 different regions in the Mexican Basin, where 67% of the nopal is produced for human consumption. The used methodology is gamma spectrometry with Hyperpure Germanium detector (HPGe) and Multichannel Analyzer (MCA) with Maestro~ software. The results show interesting aspects on the concentration of potassium in the nopal. This concentration will primarily depend on: (a) the geological characteristics of the location where the nopal was grows; (b) that potassium concentrations may vary substantially from a region to another, with the same species of nopal as a reference and (c) that this concentration may also vary from one growing season to another. 展开更多
关键词 potassium nopal (Opuntiaficus indica) gamma spectrometry K-40 HPGe.
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Contents and Changes of Potassium in Plough Layers of Xuancheng, South Anhui Province
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作者 Ka Lin Decheng Li +9 位作者 Xiaodong Song Chaolong Zu Chaoqiang Jiang Jia Shen Chengxin Ma Qin Gao Qifa Zhu Xuejun Ji Guo Zhang Lin Xue 《Agricultural Sciences》 2017年第5期348-355,共8页
Xuancheng City is the dominant tobacco-planting area of Anhui province due to the high quality of the tobacco leaves. However, the potassium content in the tobacco leaves shows a gradual decreasing trend in recent yea... Xuancheng City is the dominant tobacco-planting area of Anhui province due to the high quality of the tobacco leaves. However, the potassium content in the tobacco leaves shows a gradual decreasing trend in recent years, which may be attributed partly to the possible low potassium content in topsoil of tobacco-planting farmland. Therefore, the content data in the year of 2005-2007 of rapidly available potassium (RA-K) of 7730 topsoil samples mainly under double rice rotation or wheat/rice-rice rotation at that time and the content data of slowly available potassium (SA-K) and RA-K of 124 typical topsoil samples in the year of 2015 under tobacco-rice rotation were used and compared in order to disclose the status of topsoil potassium and to provide a guidance for reasonable potassium fertilization in Xuancheng. The results showed that in 2005-2007 RA-K content ranged from 1 mg&#183kg-1 to 844 mg&#183kg-1 with an average of 68 mg&#183kg-1, and 82.7% of topsoil samples were insufficient in RA-K (-1). Comparatively in 2015 SA-K content ranged from 230 mg&#183kg-1 to 1340 mg&#183kg-1 with an average of 595 mg&#183kg-1, and 13.7% of soil samples were insufficient in SA-K (-1);RA-K content ranged from 46 mg&#183kg-1 to 352 mg&#183kg-1 with an average of 134 mg&#183kg-1, and 25.8% of soil samples were insufficient in RA-K (-1). The above data show that RA-K content has increased gradually in farmland topsoil mainly due to fertilization since 1980s, particularly to farmland under tobacco-rice rotation, but insufficient RA-K in topsoil is still widely and serious for farmland under double rice rotation or wheat/rice-rice rotation. Under tobacco-rice rotation, RA-K insufficiency usually occurred in the farmlands which plant tobacco less than 3 years, indicating more potassium fertilizer should be applied. 展开更多
关键词 Rapidly Available potassium (RA-K) Slowly Available potassium (SA-K) TOPSOIL Tobacco-Rice Rotation Xuancheng City
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Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate 被引量:1
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作者 Haotian Jian Guoqiang Zheng +4 位作者 Lejian Chen Zheng Ning Guofu Yin Peng Zhu Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期222-231,共10页
Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig... Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success. 展开更多
关键词 Exploding foil initiator PDV Plasma spectrum Ignition mechanism Boron potassium nitrate
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Mechanical properties and acoustic emission characteristics of soft rock with different water contents under dynamic disturbance 被引量:1
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作者 Yujing Jiang Lugen Chen +4 位作者 Dong Wang Hengjie Luan Guangchao Zhang Ling Dong Bin Liang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期135-148,共14页
Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties... Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties and acoustic emission characteristics of soft rocks with different water contents under dynamic disturbance.The mechanical properties and acoustic emission characteristics of muddy sandstones at different water contents were analysed.Results of experimental studies show that water is a key factor in the mechanical properties of rocks,softening them,increasing their porosity,reducing their brittleness and increasing their plasticity.Under uniaxial compression,the macroscopic damage characteristics of the muddy sandstone change from mono-bevel shear damage and‘X’type conjugate bevel shear damage to a roadway bottom-drum type damage as the water content increases.Dynamic perturbation has a strengthening effect on the mechanical properties of samples with 60%and less water content,and a weakening effect on samples with 80%and more water content,but the weakening effect is not obvious.Macroscopic damage characteristics of dry samples remain unchanged,water samples from shear damage and tensile–shear composite damage gradually transformed into cleavage damage,until saturation transformation monoclinic shear damage.The evolution of acoustic emission energy and event number is mainly divided into four stages:loading stage(Ⅰ),dynamic loading stage(Ⅱ),yield failure stage(Ⅲ),and post-peak stage(Ⅳ),the acoustic emission characteristics of the stages were different for different water contents.The characteristic value of acoustic emission key point frequency gradually decreases,and the damage degree of the specimen increases,corresponding to low water content—high main frequency—low damage and high water content—low main frequency—high damage. 展开更多
关键词 Dynamic disturbance Soft rock Cyclic loading Acoustic emission Water content
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Determination of potassium content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach (ICP-OES)
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作者 Xiao Huan-xin Wu Jun-yi 《International Journal of Technology Management》 2014年第2期87-90,共4页
Inductively coupled plasma optical emission spectrometric approach(1CP-OES) is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element ... Inductively coupled plasma optical emission spectrometric approach(1CP-OES) is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element of potassium is conunonly found in potassium nitrate and potassium perchlorate in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that potassium nitrate content in pyrotechnics is between 10% to 60% and the potassium perchlorate content is between 20% to 70%,which counted in the content of potassium element is between 4% to 23%. Concept of this method: considering the weight of the sample is 400rag,constant volume is 1L and the concentration of potassium is between 10 mg/L to 90 mg/L in sample solution, the determination scope of the method for the potassium content would be between 1% to 23%.Further experiments proved that the fitting correlation coefficient of potassium calibration curve is 0.9997 or higher, recovery is 89.15%-100.23%.The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision. 展开更多
关键词 fireworks and firecrackers pyrotechnic compositions principal component potassium content DETERMINATION inductively coupled plasma optical emission spectrometric approach ICP-OES.
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Determination and Degradation of Potassium Bromate Content in Dough and Bread Samples Due to the Presence of Metals
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作者 Ahmad Abu-Obaid Shatha AbuHasan Basem Shraydeh 《American Journal of Analytical Chemistry》 2016年第6期487-493,共7页
Potassium bromate (PB) is used in bread making as an agent of maturation;however, it is classified as a potential carcinogen. In the present study, a rapid, simple, precise and accurate testing method has been develop... Potassium bromate (PB) is used in bread making as an agent of maturation;however, it is classified as a potential carcinogen. In the present study, a rapid, simple, precise and accurate testing method has been developed to determine the level of bromate ions in bread, which is based on a reaction of bromate ions with iodide ions in acidic medium to produce iodine (I<sub>2</sub>). The absorbance of iodine (I<sub>2</sub>) was measured at 352 nm, and bromate ions reacted with iodide during the first 3 minutes after initiation of the reaction. The proposed method has been successfully applied to the determination of bromate ions in commercial bread. In this work, we found that bromate ions alone degraded at about 400&deg;C, however, during bread making they degraded at 150&deg;C - 200&deg;C, this mightbe due to the presence of metals [Fe, Mg, Zn, Mn, Cu and Al] in flour which served as catalysts. In this study we found that the use of two grams (2 g) of PB per bag flour (60 kg) was safe. 展开更多
关键词 potassium Bromate DOUGH BREAD CATALYST Flame Atomic Absorption Inductively Coupled Plasma Mass Spectrometry
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基于新型Contention网络的滚动轴承早期故障诊断方法研究
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作者 赵俊豪 郑煜 +1 位作者 王英 王凯 《机械设计与制造工程》 2024年第3期87-91,共5页
针对滚动轴承早期故障诊断问题,为了同时建模振动信号中的高频和低频特征,实现高精度诊断,提出了一种新的模型Contention。它以一种互补的方式集成了空洞卷积和自注意力机制的优点,具有同时捕捉高频和低频信息的能力。为了验证其诊断能... 针对滚动轴承早期故障诊断问题,为了同时建模振动信号中的高频和低频特征,实现高精度诊断,提出了一种新的模型Contention。它以一种互补的方式集成了空洞卷积和自注意力机制的优点,具有同时捕捉高频和低频信息的能力。为了验证其诊断能力,首先,在完整信息原则下将振动信号连续构造成数据集;其次,搭建Contention网络并训练,其最终测试集准确度可达100%,t-SNE显示随网络层次的深入特征被明显聚类;最后,设置对照实验,将该模型与传统RNN、CNN、Transformer模型对比,证明该模型具备突出的诊断能力。 展开更多
关键词 contention网络 空洞卷积 自注意力机制 滚动轴承 早期故障诊断
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Study of the Potassium Content in Amaranth Protein Using the Gamma Spectrometry Technique
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作者 Carmenángeles Galloso Laura Vargas-Ulloa +1 位作者 Guillermo Espinosa-García Manuel Soriano-García 《材料科学与工程(中英文B版)》 2019年第2期50-55,共6页
Amaranthus is a dicotyledonous pseudocereal and one of the new world’s oldest crops,having originated from Meso-America and was a major food crop of the Aztecs.Popularity in the cultivation and consumption of Amarant... Amaranthus is a dicotyledonous pseudocereal and one of the new world’s oldest crops,having originated from Meso-America and was a major food crop of the Aztecs.Popularity in the cultivation and consumption of Amaranthus seed in the modern era began in the mid-1970s with the rediscovery and promotion of amaranth due to its superior nutritional attributes as compared to cereal grains.Amaranth plant has a high-quality protein,carbohydrates,unsaturated oil,squalene,dietary fiber,tocopherols,phenolic compounds,flavonoids,vitamins and minerals.The amaranth’s grain was collected at San Martin Pahuacan,Estado de Mexico,Mexico.The used methodology is gamma spectrometry with Hyperpure Germanium detector(HPGe)and Multichannel Analyzer(MCA)with Maestro software.The result shows a unique concentration of radioactive potassium content in the amaranth protein isolated from amaranth grains is 424.1 mg/100 g of amaranth protein.There is an excellent agreement between the amount of potassium determined by atomic absorption spectroscopy in our laboratory and the value obtained in this work using the Gamma Spectrometry Technique. 展开更多
关键词 potassium amaranth(Amaranthus hypochondriacus) GAMMA SPECTROMETRY K-40 HPGE
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