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Progress in green and efficient enrichment of rare earth from leaching liquor of ion adsorption type rare earth ores 被引量:12
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作者 Qiang He Jiang Qiu +2 位作者 Jinfa Chen Miaomiao Zan Yanfei Xiao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第3期353-364,I0001,共13页
Ion adsorption type rare earth ores(IATREOs)are a valuable strategic mineral resource in China,which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth(RE)element... Ion adsorption type rare earth ores(IATREOs)are a valuable strategic mineral resource in China,which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth(RE)elements.In the leaching process for recovering rare earth elements from IATREOs,many impurities will be leached together with rare earth elements and enter the leaching liquor.An impurity removal-precipitation enrichment technique is currently applied to selectively recovery rare earth elements from the leaching liquor with the high content of impurities and low concentration of rare earth elements by using ammonium bicarbonate in the industry.However,a high loss of rare earth elements and severe ammonia nitrogen pollution are caused by this process.Therefore,more beneficial impurities removal technologies,mainly for aluminum,and green enrichment technologies with lower pollution are now urgently needed.For this purpose,this paper analyzed two aspects of research progress in recent decades:the green separation of rare earth elements and aluminum from leaching liquor and the green and efficient enrichment of rare earth elements.Finally,an approach for the high-efficiency and green enrichment of rare earth elements from leaching liquor of the IATREOs is proposed in several aspects,including impurity inhibition leaching,neutralization and impurity removal,alkaline calcium and magnesium salt precipitation enrichment,and centrifugal extraction enrichment. 展开更多
关键词 ion adsorption type rare earth ores Leaching liquor Rare earth Aluminum Separation Non-ammonia enrichment
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Reduction leaching of rare earth from ion-adsorption type rare earths ore with ferrous sulfate 被引量:19
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作者 肖燕飞 冯宗玉 +4 位作者 胡谷华 黄莉 黄小卫 陈迎迎 龙志奇 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第9期917-923,共7页
The practice ofin-situ leaching of the ion-adsorption type rare earths ore with ammonium sulfate could only leach most of rare earth in ion-exchangeable phase, but not the colloidal sediment phase. Therefore, the redu... The practice ofin-situ leaching of the ion-adsorption type rare earths ore with ammonium sulfate could only leach most of rare earth in ion-exchangeable phase, but not the colloidal sediment phase. Therefore, the reduction leaching of rare earth from the ion-adsorption type rare earths ore with ferrous sulfate was innovatively put forward. The soak leaching process and the column leaching process were investigated in the present study. It was determined that ion-exchangeable phase could be released, and part of colloidal sediment phase rare earth could be reduction leached by the cations with reduction properties. The mechanism of reduction leaching was discussed with the Eh-pH diagram of cerium. Moreover, the stronger reduction of reductive ions, the greater acidity of leaching agent solution, and the higher reductive ion concentration, could result in the higher rare earth efficiency and the bigger ce-rium partition in the leaching liquor. In the ferrous sulfate column leaching process, the rare earth leaching rate and the rare earth effi-ciency were a little higher than with (NH4)2SO4 agent, and the rare earth efficiency and the partitioning of cerium in leaching liquor could be about 102% and 5.31%, respectively. However, the ferrous sulfate leaching process revealed some problems, so compound leaching with magnesium sulfate and a small amount of ferrous sulfate was proposed to an excellent alternative leaching agent for further studies, which may realize efficiency extraction and be environment-friendly. 展开更多
关键词 rare earth reduction leaching ferrous sulfate the ion-adsorption type rare earths ore
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Effects of organic acids on the leaching process of ion-adsorption type rare earth ore 被引量:24
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作者 Li Wang Chunfa Liao +3 位作者 Youming Yang Haibo Xu Yanfei Xiao Chunhua Yan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第12期1233-1238,共6页
To examine the activation of organic acids on the leaching process of ion-adsorption type rare earth ore(IRE-ore), the leaching behavior of rare earth(RE) and zeta potential of IRE-ore were investigated in the abs... To examine the activation of organic acids on the leaching process of ion-adsorption type rare earth ore(IRE-ore), the leaching behavior of rare earth(RE) and zeta potential of IRE-ore were investigated in the absence and presence of carboxylic acids. The results show that all the tested organic acids(acetic acid,malonic acid, citric acid, tartaric acid, succinic acid, and malic acid) can promote RE extraction. At relatively high concentrations of organic acids, the activation efficiency of organic acids on RE extraction is generally consistent with their complexation ability; whereas at their low concentrations, the change of zeta potential on the IRE-ore surface with organic acid concentration and p H has a close association with RE extraction, which indicates that organic acids can impact the surface electrical property of IREore via their adsorption/desorption, and thereby increase/decrease the affinity of RE ions to IRE-ore.Therefore the influence of organic acids on the IRE-ore surface electrical property also plays an important role in RE extraction in addition to their complexation with RE ions. 展开更多
关键词 ion-adsorption type rare earth ore Organic acid RE extraction Zeta potential Complexation
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Study on Material Composition and REE-host Forms of Ion-type RE Deposits in South China 被引量:5
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作者 张培善 陶克捷 杨主明 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第1期37-41,共5页
in the ion-type RE deposite in South China, the host rocks of REE minerals are igneous and metamorphic rocks , such as granite, granite-porphyry, granitite, muscovite granite, granodiorite, rhyolite, tuff, lamprophyre... in the ion-type RE deposite in South China, the host rocks of REE minerals are igneous and metamorphic rocks , such as granite, granite-porphyry, granitite, muscovite granite, granodiorite, rhyolite, tuff, lamprophyre, alkaline rocks, granite-gneiss, stuff, gneissic granite.These various types of rocks occurred in the environment of humid subtropical zone with a specific topographic relief. During a long-term geological process, they were weathered and alterated into montmorillonite, gibbstite, vermiculite and the dioctahedral type of clay minerals, such as kaolinite, halloysite-0. 7 nm , halloysite-1. 0 nm and ferrohalloysite. All of these clay minerals are the REE carriers. The REE in the ion-type RE deposits came from there source: 1) the REE -bearing rock-forming minerals in host rock, such as microcline and amphibole:2) the accessory minerals in host rocks, such as allanite, gadolinite-(Y), sphene , parisite-(Y), and fergusonite-(Y). For a long geological time the weathering and leaching processes caused the minerals to be disintegrated and to free REE ions. The REE cations can be adsorbed on various clay minerals associated. The categories of ion -type RE deposite depend on the species of RE minerals and the lithological characters of the host geological body in the ore deposit area. 展开更多
关键词 ion -type RE deposit Material composition RE-host forms Clay minerals Adsorption
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Behavior of leaching and precipitation of weathering crust ion-absorbed type by magnetic field 被引量:16
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作者 邱廷省 方夕辉 +1 位作者 崔立凤 房艳霞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期274-278,共5页
With weathering crust Ion-Absorbed Type Rare Earth (IATRE) ores in southern Jiangxi as an example, rare earth percolation leaching and leaching solution precipitation process research were carried out under conditio... With weathering crust Ion-Absorbed Type Rare Earth (IATRE) ores in southern Jiangxi as an example, rare earth percolation leaching and leaching solution precipitation process research were carried out under conditions of magnetic field. The effect on the rare earth leaching process such as magnetic field strength, magnetization time, magnetization manner, and other factors were discussed. The effect on the mother rare earth liquor sedimentation rate, purity, and crystallization behavior such as magnetic field strength, magnetization time, and magnetization manner were investigated. Leaching and precipitation mechanism of magnetization on IATRE were analyzed. The results showed that the magnetic treatment can improve leaching rate of weathering crust IATRE and the sedimentation rate, and reduce consumption of reagents. 展开更多
关键词 ion-absorbed type rare earth magnetic treatment LEACHING DEPOSIT rare earths
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Study on a cold-cathode H^- PIG-type ion source 被引量:4
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作者 LONG Jidong YANG Zhen +2 位作者 DONG Pan HE Xiaozhong ZHANG Kaizhi 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第4期1-4,共4页
A cold-cathode Penning Ion Gauge(PIG) type ion source as the internal ion source of an 11 MeV cyclotron is designed and tested at Institute of Fluid Physics.The design considerations and some testings are presented.Ex... A cold-cathode Penning Ion Gauge(PIG) type ion source as the internal ion source of an 11 MeV cyclotron is designed and tested at Institute of Fluid Physics.The design considerations and some testings are presented.Experimental results of Balmer-line-Emission show that the discharge characteristic,which is mainly determined by gas-flow rate,is not very sensitive to arc current and magnetic field in the operation ranges of the cyclotron.The arc power decreases and ascends while the gas-flow rate goes up from 0.5 SCCM to 20 SCCM.By improving the sealing design and reducing the machine tolerance of the source,the minimum power consumption reduces from 9 SCCM to 4 SCCM,thus having better energy efficiency and benefiting for the pumping system.Preliminary DC extractions show that H–microampere current ranges from several tens to hundreds under different operation conditions.Some problems during the experiments and future plan are discussed in the end. 展开更多
关键词 离子源 冷阴极 回旋加速器 G型 密封设计 实验过程 物理研究所 放电特性
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Lithium ion conductivity of complex hydrides incorporating multiple closo–type complex anions 被引量:2
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作者 Naoki Toyama Sangryun Kim +5 位作者 Hiroyuki Oguchi Toyoto Sato Shigeyuki Takagi Masaru Tazawa Genki Nogami Shin-ichi Orimo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期84-87,共4页
We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type c... We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type complex hydrides comprised [B12H12]^2-, [B11H11]^2-, and [B10H10]^2- complex anions. In addition, increasing the LiBH4 content in the starting materials increased the amounts of [B11H11]^2- and [B10H10]^2-, leading to an improved ion conductivity of the prepared sample. The present study offers useful insights into strategies for controlling the complex anion composition in emerging solid electrolytes of closo-type complex hydrides at the molecular level, and improving their ionic conductivities. 展开更多
关键词 Closo-type COMPLEX HYDRIDE Solid ELECTROLYTE Lithium ion conductivity MULTIPLE COMPLEX ANionS
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Adsorption behavior of uranyl ions onto amino-type adsorbents prepared by radiation-induced graft copolymerization 被引量:3
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作者 迟洪影 刘西艳 +7 位作者 马红娟 杨晓娟 虞鸣 张建勇 王敏 李景烨 Hiroyuki Hoshina Noriaki Seko 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第1期20-26,共7页
Amino-type adsorbents(ATAs) were prepared by radiation-induced graft copolymerization of 4-hydroxybutyl acry late glycidyl ether(HB) onto a polyethylene-coated polypropylene(PE/PP) duplex fiber of a non-woven fabric,a... Amino-type adsorbents(ATAs) were prepared by radiation-induced graft copolymerization of 4-hydroxybutyl acry late glycidyl ether(HB) onto a polyethylene-coated polypropylene(PE/PP) duplex fiber of a non-woven fabric,and modified with different amines of ethylenediamine(EDA),diethylenetriamine(DETA),triethylenetetramine(TETA) and diethylamine(DEA).The adsorption behavior of uranyl ions onto the ATAs was studied in batch experiments.The effects of the contact time,initial concentration of the ions,temperature,and pH value.The salinity were investigated along with the adsorption kinetics and the adsorption isotherms.The kinetic experimental data followed the pseudo second-order kinetic model,and the adsorption isotherms correlated well with the Langmuir model.The ATAs showed good efficiency in adsorbing uranyl ions,with the best saturation adsorption capacity being 64.26 mg g^(-1) for ATA-DETA within 120 min.The temperature dependence of ATADETA was quite abnormal and the quickest behavior was obtained at 25 ℃.ATAs showed good adsorption capacity over a wide pH range of 4.0-8.5,and HCl could be used in the elution process.Salinity of the solution had great effect on the adsorption capacity,3.5%salinity resulted in a 55%loss of capacity from ATA-DETA.The selectivity of ATA-DETA showed an order of:UO_2^(2+)≈Fe^(3+)> Zn^(2+) > VO_3^- > Co^(2+) > Ni^(2+). 展开更多
关键词 吸附行为 铀酰离子 接枝共聚 辐射诱导 吸附剂 基型 LANGMUIR模型 吸附等温线
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Recycling of Cobalt by Liquid Leaching from Waste 18650-Type Lithium-Ion Batteries
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作者 Liangmou Yu Bo Shu Shiwen Yao 《Advances in Chemical Engineering and Science》 2015年第4期425-429,共5页
In this work, we recover cobalt from waste 18650-type lithiumion batteries by acid leaching. The cathode material is completely dissolved, after leaching waste batteries by using 10 mol/L industrial sulfuric acid at 7... In this work, we recover cobalt from waste 18650-type lithiumion batteries by acid leaching. The cathode material is completely dissolved, after leaching waste batteries by using 10 mol/L industrial sulfuric acid at 70℃ for 1 h. The rate of cobalt leaching is nearly 100%. Removal of sodium carbonate, iron, aluminum and other impurities from the leaching solution was well performed by adjusting the pH to 2-3 with stirring vigorously. Finally, under the conditions of 55℃-60℃ of 240 A/m2 current density, electrodeposition current efficiency was 90.01%, the quality of the electrical output achieved cobalt 1A standard electrolytic cobalt, cobalt until greater than 90% yield. The process is easy and suitable for large-scale lithiumion batteries used in the recovery of valuable metals. 展开更多
关键词 Component COBALT 18650-type LITHIUM-ion Battery LEACHING ELECTRODEPOSITion
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Removal of Anionic Metal Ions from Wastewater by Hydroxide-type Adsorbents
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作者 Toyohisa Fujita Gjergj Dodbiba +1 位作者 Jun Sadaki Atsushi Shibayama 《过程工程学报》 CAS CSCD 北大核心 2006年第3期357-362,共6页
Generally speaking,anionic metal concentrations in wastewater from industries and mineral processing plants are well above the allowed limits for effluent set by the Ministry of Environment of Japan. Nowadays,the remo... Generally speaking,anionic metal concentrations in wastewater from industries and mineral processing plants are well above the allowed limits for effluent set by the Ministry of Environment of Japan. Nowadays,the removal of anionic ions has been considered difficult and development of new process is desperately needed. In this paper,we report the development of three hydroxide-type adsorbents,illustrating their adsorption efficiency in removing As,Se,Mo and Sb ions from aqueous solutions. The main finding of this work was that the adsorption behavior was influenced very much by both the pH and the adsorbent concentration. Nevertheless,the newly developed hydroxide-type adsorbents were very effective in reducing the concentration of those anionic ions. 展开更多
关键词 hydroxide-type adsorbent adsorption anionic metal ions REMOVAL WASTEWATER
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Ion Torrent测序技术检测Ⅰ型神经纤维瘤病患者NF1基因突变 被引量:3
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作者 朱艳慧 胡朝晖 +3 位作者 毕欣 喻长顺 许若思 王晓春 《临床检验杂志》 CAS CSCD 北大核心 2013年第11期821-824,共4页
目的评价Ion Torrent测序技术检测Ⅰ型神经纤维瘤(NF1)基因及其突变类型的可行性。方法提取12例NF1患者的外周血DNA,用Ion Torrent个体化基因测序仪(PGM)对患者NF1基因进行测序,用Sanger测序法验证NF1基因相应的突变位点,Ion Torrent PG... 目的评价Ion Torrent测序技术检测Ⅰ型神经纤维瘤(NF1)基因及其突变类型的可行性。方法提取12例NF1患者的外周血DNA,用Ion Torrent个体化基因测序仪(PGM)对患者NF1基因进行测序,用Sanger测序法验证NF1基因相应的突变位点,Ion Torrent PGM检测后覆盖缺失的外显子样本用Sanger测序法重新检测。结果检测到10例患者存在NF1基因致病突变,其中2种无义突变,5种小缺失或插入突变,1种错义突变,2种剪接突变。2例患者未检测到致病突变。结论 Ion Torrent测序技术检测含有大量外显子的NF1基因快速、准确;NF1基因突变可导致氨基酸密码子提前终止。 展开更多
关键词 神经纤维瘤病 I型神经纤维瘤基因 ion Torrent测序 Sanger测序
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Geochemical Characteristics of Rare Earth Elements in Guposhan Granite Complex and Their Petrogenetic Implication 被引量:1
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作者 杨学明 张培善 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第1期60-65,共6页
In this paper the geochemical characteristics of rare earth elements in Guposhan granite complex in Nanling Area,South China,is systematically studied,and the balance of REE distribution in rock-forming minerals, whic... In this paper the geochemical characteristics of rare earth elements in Guposhan granite complex in Nanling Area,South China,is systematically studied,and the balance of REE distribution in rock-forming minerals, which contain only 21.47~29.71 wt% of total REE in granites,is calculated.The petrogenetic relationship be- tween three different stages of the granites in the complex is discussed,and a geochemical model is suggested for the formation of granitic magma in early stage by partial melting of the crustal basement rocks containing more REE than that in the late stage.It shows that a ion-adsorption type of REE deposit could ocuur in the weath- ering crust on the early stage granite.Rb-Sr isotope isochron dating of the first stage medium-coarse-grained K-feldspar granite shows that its age is 146.5 Ma and initial ^(87)Sr/^(86)Sr ratio is 0.71198. 展开更多
关键词 Rare earth elements GRANITE Petrogenetic mechanism Geochemical model ion-adsorption type REE deposit
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压电型机械门控离子通道组件1在大鼠压力性损伤中的作用机制
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作者 孙家琪 卞璐 +2 位作者 史文涛 吴学潮 鲁晓杰 《中国组织工程研究》 CAS 北大核心 2025年第8期1578-1584,共7页
背景:压力性损伤的发生机制复杂,哪些因素在其发生中起到核心作用,这些因素具体又是如何发生的尚不完全清楚。目的:探讨压电型机械门控离子通道组件1(piezo-type mechanosensitive ion channel component 1,PIEZO1)与压力性损伤发生的... 背景:压力性损伤的发生机制复杂,哪些因素在其发生中起到核心作用,这些因素具体又是如何发生的尚不完全清楚。目的:探讨压电型机械门控离子通道组件1(piezo-type mechanosensitive ion channel component 1,PIEZO1)与压力性损伤发生的关系。方法:①细胞实验:采用不同浓度的PIEZO1激动剂Yoda1干预人永生化角质形成细胞(HaCaT),检测细胞活性、钙离子内流及PIEZO1、凋亡相关蛋白的表达。②动物实验:采用随机数字表法将12只SD大鼠随机分为4组,每组3只:对照组大鼠不进行任何处理,1,2,3 mm组分别采用厚度1,2,3 mm的磁铁在大鼠背部两侧压迫1 h,建立压力性损伤模型,造模后切除全部创面组织,分别进行苏木精-伊红、Masson、免疫荧光染色及Western blot检测。结果与结论:①细胞实验:活/死细胞染色结果显示,随着Yoda1浓度(0,2.5,5,10μmol/L)的升高,HaCaT细胞凋亡增加;随着Yoda1浓度(0,5,10μmol/L)的升高,HaCaT细胞钙离子内流增加,并且随着处理时间的延长,钙离子内流增多;Western blot检测结果显示,与对照组(0μmol/L Yoda1干预)比较,5,10μmol/L Yoda1干预可提升HaCaT细胞中BAX、TG2、PIEZO1蛋白的表达,降低Bcl-2蛋白的表达;②动物实验:苏木精-伊红与Masson染色结果显示,3个实验组压迫部位皮肤结构被破坏,皮下脂肪液化坏死,胶原蛋白稀疏且排列紊乱,并且随着磁铁厚度(压力)的增加,压迫部位皮肤组织结构破坏程度加重;免疫荧光染色与Western blot检测结果显示,与对照组比较,3个实验组大鼠BAX、TG2、Yap1与PIEZO1蛋白表达升高,Bcl-2蛋白表达降低,并且随着磁铁厚度(压力)的增加,相关蛋白表达值改变更加明显;③结果表明:皮肤受压会激活PIEZO1使钙离子大量内流,随着所受压力的不断增加,最终导致钙超载后的细胞凋亡。 展开更多
关键词 压力性损伤 压电型机械门控离子通道组件1 PIEZO1 钙超载 HACAT细胞
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A Scenario to Provide Atomic Data for Fusion Research in the Stage of Precision Physics 被引量:1
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作者 李家明 高翔 +2 位作者 程诚 张小乐 青波 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第3期335-340,共6页
In order to provide abundant atomic data for fusion research in the stage of precision physics, a scenario, being a combination of indispensable theoretical calculations and bench-mark experimental measurements, is pr... In order to provide abundant atomic data for fusion research in the stage of precision physics, a scenario, being a combination of indispensable theoretical calculations and bench-mark experimental measurements, is proposed. Such abundant atomic data are compiled mainly by theoretical calculations. Accuracies of such abundant data (i.e., atomic energy levels and cor- responding cross sections) are ascertained only by a finite number of bench-mark experimental measurements based on analytical calculation of scattering matrices. 展开更多
关键词 R-matrix type methods electron-ion collision full-relativistic calculations
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Li^+ extraction/insertion reaction with Mg_2Mn_(0.5)Ti_(0.5)O_4 inverse spinel in the aqueous phase 被引量:1
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作者 JANG Jinhe DONG Dianquan CHEN Guanghui LIU Jiaqiang LI Jianlong 《Rare Metals》 SCIE EI CAS CSCD 2007年第6期536-540,共5页
An inverse spinel-type metal oxide, magnesium-manganese-titanium oxide (Mg2Mn0.5Ti0.5O4), were prepared using the coprecipitation/thermal crystallization method. The extraction/insertion reaction with this material ... An inverse spinel-type metal oxide, magnesium-manganese-titanium oxide (Mg2Mn0.5Ti0.5O4), were prepared using the coprecipitation/thermal crystallization method. The extraction/insertion reaction with this material was investigated by X-ray, saturation capacity of exchange, pH titration, and distribution coefficient (Kd) measurement. The acid treatments of Mg2Mn0.5Ti0.5O4 caused Mg^2+ extractions of more than 81%, whereas the dissolutions of Mn^4+ and Ti^4+ were less than 10%. The experimental results proved that the acid-treated sample has a capacity of exchange 56 mg·g^-1 for Li^+ in the solution. The chemical analysis showed that the Li^+ extraction/insertion progressed mainly by ion-exchange mechanism and surface adsorption. 展开更多
关键词 extraction/insertion reaction inverse spinel-type metal oxides ion-exchange mechanism Mg2Mn0.5Ti0.5O4
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Classification of B and Y Ions in Peptide MS/MS Spectra Based on Machine Learning
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作者 Xinming Li 《Journal of Computer and Communications》 2023年第3期99-109,共11页
In proteomics, b and y ions serve as the backbone ions for peptide sequencing in tandem mass spectrometry. Leveraging the existing ion recognition and separation methods, this article proposes a novel ion classificati... In proteomics, b and y ions serve as the backbone ions for peptide sequencing in tandem mass spectrometry. Leveraging the existing ion recognition and separation methods, this article proposes a novel ion classification approach that combines machine learning with graph theory. By incorporating graph features, the method achieves higher accuracy and efficiency in ion type recognition, with the graph features playing a critical role in the classification process. Specifically, the method achieves a recall rate of nearly 90% for b and y ions, demonstrating its effectiveness in pre-processing de novo sequencing and improving its accuracy. The proposed method represents advancement in ion classification and has the potential to improve the accuracy and efficiency of de novo sequencing. 展开更多
关键词 ion-type Classification Machine Learning LightGBM PROTEOMICS Tandem Mass Spectrometry
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Electrical and structural properties of diamond films implanted by various doses of oxygen ions
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作者 胡晓君 叶健松 +2 位作者 郑国渠 曹华珍 谭红川 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2170-2174,共5页
Oxygen-doped diamond films are prepared by implanting various dose oxygen ions into the diamond films synthesized by hot filament chemical vapour deposition, and their electrical and structural properties are investig... Oxygen-doped diamond films are prepared by implanting various dose oxygen ions into the diamond films synthesized by hot filament chemical vapour deposition, and their electrical and structural properties are investigated. Hall effect measurements show that lower dose oxygen ion implantation is beneficial to preparing n-type diamonds. The carrier concentration increases with the dose increasing, indicating that oxygen ions supply electrons to the diamonds. The results of AES spectrum indicate that oxygen ions are doped into the diamond films, and the O-implanted depth is around 0.1μm. Raman spectrum measurements indicate that the lower dose oxygen ion implantation at 10^14 cm^-2 or 10^15 cm^-2 is favourable for producing less damaged O-doDed diamond films. 展开更多
关键词 diamond films N-type OXYGEN ion implantation
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General anesthesia mediated by effects on ion channels 被引量:3
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作者 Cheng Zhou Jin Liu Xiang-Dong Chen 《World Journal of Critical Care Medicine》 2012年第3期80-93,共14页
Although it has been more than 165 years since the first introduction of modern anesthesia to the clinic, there is surprisingly little understanding about the exact mechanisms by which general anesthetics induce uncon... Although it has been more than 165 years since the first introduction of modern anesthesia to the clinic, there is surprisingly little understanding about the exact mechanisms by which general anesthetics induce unconsciousness. As a result, we do not know how general anesthetics produce anesthesia at different levels. The main handicap to understanding the mechanisms of general anesthesia is the diversity of chemically unrelated compounds including diethyl ether and halogenated hydrocarbons, gases nitrous oxide, ketamine, propofol, benzodiazepines and etomidate, as well as alcohols and barbiturates. Does this imply that general anesthesia is caused by many different mechanisms? Until now, many receptors, molecular targets and neuronal transmission pathways have been shown to contribute to mechanisms of general anesthesia. Among these molecular targets, ion channels are the most likely candidates for general anesthesia, in particular γ-aminobutyric acid type A, potassium and sodium channels, as well as ion channels mediated by various neuronal transmitters like acetylcholine, amino acids amino-3-hydroxy-5-methyl-4-isoxazolpropionic acid or N-methyl-D-aspartate. In addition, recent studies have demonstrated the involvement in general anesthesia of other ion channels with distinct gating properties suchas hyperpolarization-activated, cyclic- nucleotide-gated channels. The main aim of the present review is to summarize some aspects of current knowledge of the effects of general anesthetics on various ion channels. 展开更多
关键词 General ANESTHESIA ion CHANNELS γ-aminobutyric acid type A receptors HYPERPOLARIZATion activated cyclic NUCLEOTIDE Potassium CHANNELS GLUTAMATERGIC ion CHANNELS Sodium CHANNELS
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浸矿作用下离子型稀土典型重金属释放规律研究
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作者 郭钟群 罗飞跃 +3 位作者 唐韬 谢少俊 刘强强 冯秀娟 《黄金科学技术》 CSCD 北大核心 2024年第6期1056-1067,共12页
浸矿场地土壤重金属污染严重制约离子型稀土资源绿色开发。在原地浸矿过程中,浸矿液与稀土阳离子发生离子交换反应,同时置换出部分重金属离子,导致土壤重金属活化,进而造成土壤及地下水重金属污染。通过开展不同浓度MgSO_(4)浸矿条件下... 浸矿场地土壤重金属污染严重制约离子型稀土资源绿色开发。在原地浸矿过程中,浸矿液与稀土阳离子发生离子交换反应,同时置换出部分重金属离子,导致土壤重金属活化,进而造成土壤及地下水重金属污染。通过开展不同浓度MgSO_(4)浸矿条件下离子型稀土模拟浸矿试验,揭示了浸矿液浓度对离子型稀土重金属Cu、Zn、Pb和Tl释放的影响规律,通过相关性分析和多元线性回归分析,对重金属含量与影响因素进行解析。研究结果表明:在不同浓度MgSO_(4)的浸矿作用下,典型重金属呈现纵向迁移的趋势。重金属Cu、Pb、Tl含量与MgSO_(4)浓度之间存在负相关关系,Zn含量与MgSO_(4)浓度相关性不显著,Cu主要富集在中层土壤,Zn主要富集在中下层土壤,Pb和Tl主要富集在下层土壤。土壤pH值与Eh值呈显著负相关,土壤pH值、Eh值与典型重金属存在相关性。研究结果为矿区土壤重金属污染防治与绿色开采提供理论依据。 展开更多
关键词 离子型稀土 原地浸矿 土壤环境 重金属污染 相关性分析 多元线性回归分析
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High Density Fluorine Negative-Ion Source Generated by Utilizing Magnetized SF<sub>6</sub>
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作者 M. Abid Imtiaz Tetsu Mieno 《Journal of Modern Physics》 2014年第2期89-91,共3页
In a magnetized plasma column generated from an electronegative gas, negative-ions accumulate around the plasma column via radial diffusion. In this study, a dc discharge is applied in SF6 gas to produce a plasma colu... In a magnetized plasma column generated from an electronegative gas, negative-ions accumulate around the plasma column via radial diffusion. In this study, a dc discharge is applied in SF6 gas to produce a plasma column, and the radial density profile of negative-ions is measured by Langmuir probes using the modified Bohm criterion. The gas pressure and discharge current dependences of negative-ion density are also measured. It is found that the negative-ion density of 8.0 × 1017 m-3 is obtained around the plasma column at r = 1.0 cm when SF6 pressure is 0.13 Pa and discharge current is 0.50 A. The negative-ion density has radial gradient, and the electron density is much lower in this region. 展开更多
关键词 FLUORINE NEGATIVE-ion ion Source String-type PLASMA Radial Diffusion Langmuir Probe MAGNETIZED PLASMA Sulfur HEXAFLUORIDE
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