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The Even-Odd Rule on Single Covalent-Bonded Structural Formulas as a Modification of Classical Structural Formulas of Multiple-Bonded Ions and Molecules 被引量:9
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作者 Geoffroy Auvert 《Open Journal of Physical Chemistry》 2014年第4期173-184,共12页
In organic chemistry, as defined by Abegg, Kossel, Lewis and Langmuir, compounds are normally represented using structural formulas called Lewis structures. In these structures, the octet rule is used to define the nu... In organic chemistry, as defined by Abegg, Kossel, Lewis and Langmuir, compounds are normally represented using structural formulas called Lewis structures. In these structures, the octet rule is used to define the number of covalent bonds that each atom forms with its neighbors and multiple bonds are frequent. Lewis’ octet rule has unfortunately shown limitations very early when applied to non-organic compounds: most of them remain incompatible with the “rule of eight” and location of charges is uncertain. In an attempt to unify structural formulas of octet and non-octet molecules or single-charge ions, an even-odd rule was recently proposed, together with a procedure to locate charge precisely. This even-odd rule has introduced a charge-dependent effective-valence number calculated for each atom. With this number and the number of covalent bonds of each element, two even numbers are calculated. These numbers are both used to understand and draw structuralformulas of single-covalent-bonded compounds. In the present paper, a procedure is proposed to adjust structural formulas of compounds that are commonly represented with multiple bonds. In order to keep them compatible with the even-odd rule, they will be represented using only single covalent bonds. The procedure will then describe the consequences of bond simplification on charges locations. The newly obtained representations are compared to their conventional structural formulas, i.e. single-bond representation vs. multiple-bond structures. Throughout the comparison process, charges are precisely located and assigned to specific atoms. After discussion of particular cases of compounds, the paper finally concludes that a rule limiting representations of multiplecovalent bonds to single covalent bonds, seems to be suitable for numerous known compounds. 展开更多
关键词 multiple BOND SINGLE BOND COVALENT BOND Molecule ion Even-Odd RULE Structural Formula
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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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Sorption Characteristics for Multiple Adsorption of Heavy Metal Ions Using Activated Carbon from Nigerian Bamboo 被引量:5
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作者 Ademiluyi Falilat Taiwo Nze Jane Chinyere 《Journal of Materials Science and Chemical Engineering》 2016年第4期39-48,共10页
Sorption characteristics of multiple adsorption of six heavy metal ions often found in refinery waste waters using activated carbon from Nigerian bamboo was investigated. The bamboo was cut, washed and dried. It was c... Sorption characteristics of multiple adsorption of six heavy metal ions often found in refinery waste waters using activated carbon from Nigerian bamboo was investigated. The bamboo was cut, washed and dried. It was carbonized between 350℃ - 500℃, and activated at 800℃ using nitric acid. Simultaneous batch adsorption of different heavy metal ions (Cd<sup>2+</sup>, Ni<sup>2+</sup>, Pb<sup>2+</sup>, Cr<sup>3+</sup>, Cu<sup>2+</sup> and Zn<sup>2+</sup>) in same aqueous solution using activated carbon from Nigerian bamboo was carried out. The adsorption process had a better fit for the Freundlich, Temkin isotherm and Dubinin-Radushke-vich (DRK) isotherm models but could not fit well into Langmuir isotherm. Adsorption isotherms showed that there is competition among various metals for adsorption sites on Nigerian bamboo. The DRK model was used to determine the nature of the sorption process and was found to be physical and chemical, with sorption energy of metal ions ranging from (7 - 10 kJ/mol). The adsorption of Cd<sup>2+</sup>, Zn<sup>2+</sup>, Pb<sup>2+</sup> and Ni<sup>2+</sup> ions was chemisorptions and that of Cu<sup>2+</sup> and Cr<sup>3+</sup> ions was cooperative adsorption. Therefore, this study revealed that Nigerian bamboo can serve as a good source of activated carbon with multiple and simultaneous metalions—removing potentials and may serve as a better replacement for commercial activated carbons in applications that warrant their use. 展开更多
关键词 multiple Batch Adsorption Heavy Metal ions Activated Carbon Nigerian Bamboo
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Cadmium-containing Wastewater Induced by SRB:Effect of Multiple Ions and Mineralization Process
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作者 WANG Jiyong ZHOU Jie +1 位作者 HE Wei HUANG Pinyuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2021年第6期927-933,共7页
The effects of various general and heavy metal ions in acidic cadmium-containing wastewater on SBR desulfurization and cadmium removal under different concentrations were studied.CrO_(4)^(2-) and S^(2-) inhibited SRB ... The effects of various general and heavy metal ions in acidic cadmium-containing wastewater on SBR desulfurization and cadmium removal under different concentrations were studied.CrO_(4)^(2-) and S^(2-) inhibited SRB mineralization,and Mg^(2+),Ca^(2+),Fe^(2+),and Fe^(3+) promoted SRB mineralization at low concentration(<50 mg/L).The inhibitory concentrations of Cu^(2+),Mn^(2+),Co^(2+),Zn^(2+),Pb^(2+),Hg^(2+),Cr^(3+),and Ni^(2+) were 10,30,2,20,25,5,30 mg/L,respectively.The inhibition order was Co^(2+)>Hg^(2+)>Cu^(2+)>Ni^(2+)>Zn^(2+)>Pb^(2+)>Mn^(2+)>Cr^(3+).Furthermore,the inverted microscopy and scanning electron microscopy(SEM)were used to observe the sediment crystallization process from macroscopic and microscopic viewpoints in the optimized ion environment.The experimental results show that under the mineralization of SRB,cadmium sediment crystallization is mainly divided into the rapid growth of bacteria,crystal nucleus production,block formation,and crystallization occuration.At the same time,X-ray diffraction(XRD)and energy-dispersive spectra(EDS)have also confirmed the sediment and crystallization. 展开更多
关键词 SRB mineralization process CADMIUM multiple ions
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Helium-hydrogen synergistic effects on swelling in in-situ multiple-ion beams irradiated steels
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作者 Haocheng Liu Jia Huang +12 位作者 Liuxuan Cao Yue Su Zhiying Gao Pengfei Ma Songqin Xia Wei Ge Qingyuan Liu Shuang Zhao Yugang Wang Jinchi Huang Zhehui Zhou Pengfei Zheng Chenxu Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期82-88,共7页
The development of reliable fusion energy is one of the most important challenges in this century.The accelerated degradation of structural materials in fusion reactors caused by neutron irradiation would cause severe... The development of reliable fusion energy is one of the most important challenges in this century.The accelerated degradation of structural materials in fusion reactors caused by neutron irradiation would cause severe problems.Due to the lack of suitable fusion neutron testing facilities,we have to rely on ion irradiation experiments to test candidate materials in fusion reactors.Moreover,fusion neutron irradiation effects are accompanied by the simultaneous transmutation production of helium and hydrogen.One important method to study the He-H synergistic effects in materials is multiple simultaneous ion beams(MSIB)irradiation that has been studied for decades.To date,there is no convincing conclusion on these He-H synergistic effects among these experiments.Recently,a multiple ion beam in-situ transmission electron microscopy(TEM)analysis facility was developed in Xiamen University(XIAMEN facility),which is the first triple beam system and the only in-running in-situ irradiation facility with TEM in China.In this work,we conducted the first high-temperature triple simultaneous ion beams irradiation experiment with TEM observation using the XIAMEN facility.The responses to in-situ triple-ion beams irradiation in austenitic steel 304L SS and ferritic/martensitic steel CLF-1 were studied and compared with the results in dual-and single-ion beam(s)irradiated steels.Synergistic effects were observed in MSIB irradiated steels.Helium was found to be critical for cavity formation,while hydrogen has strong synergistic effect on increasing swelling. 展开更多
关键词 helium–hydrogen synergistic effect multiple ion beams structural material SWELLING
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Multiple Ionization of Argon Induced by Carbon Ions at 20-500 keV/u Energies
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作者 牛书通 刘文彪 +6 位作者 杨爱香 韩承志 胡伟 温志文 高志民 邵剑雄 陈熙萌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期50-53,共4页
We measure the multiple ionization cross-section ratios Rk1 of Ar impacted by Cw+ (q= 1-3) ions in the energy range of 20-500 keV/u. The measured ratios Rkl increase with the projectile energy at lower energies, an... We measure the multiple ionization cross-section ratios Rk1 of Ar impacted by Cw+ (q= 1-3) ions in the energy range of 20-500 keV/u. The measured ratios Rkl increase with the projectile energy at lower energies, and reach the maximum at energies of 50-150 keV/u, then decrease for higher energies, We also use the classical over barrier ionization model to calculate the ratios Rk1, and the calculation results are in good agreement with the data, which suggest that the multiple ionization process is described by the sequential over-barrier ionization process, 展开更多
关键词 In multiple ionization of Argon Induced by Carbon ions at 20-500 keV/u Energies
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Multiple ionization of argon accompanied by electron loss and capture of 0.22-6.35 MeV C^q+ ions
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作者 陈林 陈熙萌 +9 位作者 邵剑雄 鲁彦霞 丁宝卫 崔莹 高志民 刘玉文 杜娟 谢江山 孙光智 刘兆远 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2378-2383,共6页
In this paper a projectile ions recoil ions coincidence technique is employed to investigate the target ionization and projectile charge state changing processes in the collision of 0.22-6.35 MeV Cq^+ (q = 1 - 4) i... In this paper a projectile ions recoil ions coincidence technique is employed to investigate the target ionization and projectile charge state changing processes in the collision of 0.22-6.35 MeV Cq^+ (q = 1 - 4) ions with argon atoms. The partial cross section ratios of the double, triple, quadruplicate ionization to the single ionization (or the single capture) of argon associated with single electron loss (or single electron capture) by the projectile are measured and compared with the previous experimental results. In the present experiment, it is observed that the ratios of ionization cross sections R associated with single loss and single capture depend strongly on the projectile charge state and vary significantly with different reaction channels as impact energy increases. In addition, this paper gets empirical scaling laws for the ionization cross section ratios R corresponding to the projectile single loss and finds that the ratios of the double ionization to the single ionization associated with single electron capture remain constant in the present energy range. 展开更多
关键词 multiple ionization electron loss electron capture ion-atom collisions
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Multiplicity dependence of charged particle,? meson, and multistrange particle productions in p + p collisions at s^(1/2) = 200 GeV from PYTHIA simulation 被引量:2
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作者 Sheng-Hui Zhang Long Zhou +5 位作者 Yi-Fei Zhang Ming-Wei Zhang Cheng Li Ming Shao Yong-Jie Sun Ze-Bo Tang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第9期236-241,共6页
We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multipl... We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multiple parton interactions and gluon contributions is studied and found to be a possible source of the splitting of the particle yields as a function of p_T with respect to the multiplicity. No obvious particle species dependence of the splitting is observed.The multiplicity dependence of the ratios Kˉ/πˉ, K^+/π^+,/πˉ, p/π^+, and K_s^0 at mid-rapidity in p+ p collisions is found to follow a tendency similar to that in Au t Au collisions at (s_(NN))^(1/2) = 200 GeV at the Relativistic Heavy Ion Collider, indicating similar underlying initial production mechanisms despite the differences in the initial colliding systems. 展开更多
关键词 Particle production HEAVY-ion COLLISionS Small system multiple PARTON interactions GLUON contributions
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Transient Receptor Potential Melastatin 3 and Intracellular Calcium in Natural Killer Cells in Multiple Sclerosis
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作者 Laura Clarke Simon L. Broadley +4 位作者 Thao Nguyen Samantha Johnston Natalie Eaton Donald Staines Sonya Marshall-Gradisnik 《International Journal of Clinical Medicine》 2018年第7期541-565,共25页
Background: Natural killer (NK) cell phenotypes have reported to be implicated in the pathomechanism of Multiple Sclerosis (MS). Several investigators have observed reduced peripheral numbers, reduced cytotoxic activi... Background: Natural killer (NK) cell phenotypes have reported to be implicated in the pathomechanism of Multiple Sclerosis (MS). Several investigators have observed reduced peripheral numbers, reduced cytotoxic activity, and altered CD56Dim and CD56Bright NK cell phenotypes. This current project, for the first time, investigates the NK cell cytotoxicity, calcium mobilisation and transient receptor potential melastatin 3 (TRPM3) surface expression. Methods: NK cell cytotoxic activity and calcium signaling were examined in CD56Dim and CD56Bright NK cells before and after stimulation using Ionomycin, Pregnenolone sulphate, 2-Aminoethoxydiphenyl borate and Thapsigargin. Purified NK cells were labelled with antibodies to determine TRPM3, CD69 and CD107a surface expression using flow cytometry. Results: Twenty-two MS patients and 22 healthy controls were recruited for this project. Twelve of the 22 previously received Alemtuzumab (Lemtrada&reg;) and the remaining ten reported nil medication. We report TRPM3 was significantly increased in untreated MS patients compared with healthy controls and treated MS patients (p-value 0.034). There was a significant decrease in CD69 surface expression on CD56Dim NK cell phenotype for untreated MS patients (p-value 0.031) and treated MS patients (p-value 0.036). We report altered calcium mobilisation in CD56Bright NK cells and to a lesser extent CD56Dim NK cells between healthy controls, treated and untreated MS patients. Conclusion: This investigation suggests variations in TRPM3 expression and calcium mobilisation of NK cells may be implicated in the pathogenesis of MS. Further investigation is required to determine the mechanism by which alemtuzumab alters calcium signaling in NK cells. 展开更多
关键词 Natural KILLER Cells multiple SCLEROSIS CALCIUM SIGNALLING Transient RECEPTOR Potential Melastatin 3 ion CHANNELS
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基于光谱特征的多重金属离子与DOM结合特性
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作者 胡斌 陈婷 +2 位作者 张楠楠 施玥 包天力 《环境科学与技术》 CAS CSCD 北大核心 2024年第3期119-126,共8页
通过淬灭滴定实验,文章采用同步荧光光谱和傅里叶红外光谱(FTIR)结合二维相关光谱分析,探究Cu^(2+)和Cd^(2+)多重离子与溶解态有机质(DOM)结合特性。研究结果表明,(1)DOM与Cu^(2+)和Cd^(2+)结合稳定常数(lg KM)分别为4.75~5.18和3.71~4.... 通过淬灭滴定实验,文章采用同步荧光光谱和傅里叶红外光谱(FTIR)结合二维相关光谱分析,探究Cu^(2+)和Cd^(2+)多重离子与溶解态有机质(DOM)结合特性。研究结果表明,(1)DOM与Cu^(2+)和Cd^(2+)结合稳定常数(lg KM)分别为4.75~5.18和3.71~4.12,Cu^(2+)与DOM的结合能力要强于Cd^(2+)。(2)Cd^(2+)浓度为0和100μmol/L时,DOM点位与Cu^(2+)的结合顺序均为430~500 nm>330~420 nm,且Cd^(2+)存在时Cu^(2+)与DOM的lg KM为4.56~4.95。对比结果表明Cd^(2+)的存在并未影响DOM点位与Cu^(2+)的结合顺序,但减弱了DOM与Cu^(2+)的结合能力。(3)FTIR结果表明,Cd^(2+)浓度为0和100μmol/L时DOM官能团与Cu^(2+)结合顺序依次为酚类C-O>酰胺N-H>酰胺C=O>羧基C=O>芳香族C-H>多糖C-O和酰胺N-H>酰胺C=O>酚类C-O>芳香族C-H>多糖C-O。Cd^(2+)与酚类C-O结合后影响了Cu^(2+)与DOM中酚类C-O和羧基C=O官能团的结合。水环境中多重金属离子共存时的生物有效性和生态风险应受到关注。 展开更多
关键词 荧光光谱 多重金属离子 有机质 傅里叶红外光谱 二维相关光谱分析
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适用于宽温度范围的锂离子电池SOC估计方法
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作者 胡雪峰 常先雷 +2 位作者 刘肖肖 徐威 张文彬 《储能科学与技术》 CAS CSCD 北大核心 2024年第9期2983-2994,共12页
精确的荷电状态(SOC)估计是确保动力电池安全稳定运行的关键所在。然而,在实际应用中,环境温度的变化以及噪声干扰等因素使得SOC的精确估计变得困难重重。为了解决这一问题,本文提出一种基于多新息自适应鲁棒无迹卡尔曼滤波(MIARUKF)算... 精确的荷电状态(SOC)估计是确保动力电池安全稳定运行的关键所在。然而,在实际应用中,环境温度的变化以及噪声干扰等因素使得SOC的精确估计变得困难重重。为了解决这一问题,本文提出一种基于多新息自适应鲁棒无迹卡尔曼滤波(MIARUKF)算法的宽温度范围下锂离子电池SOC多时间尺度联合估计方法,该算法在无迹卡尔曼滤波(UKF)算法的基础上,融合多新息理论、自适应滤波与鲁棒算法。所提算法利用多新息向量对状态估计值进行修正,并对噪声协方差进行及时更新,从而提高SOC的估计精度,通过引入H∞滤波算法来提高该算法的鲁棒性。同时为了降低电池管理系统(BMS)的计算负担,使用UKF算法在宏观时间尺度上在线估计模型参数,采用MIARUKF算法在微观时间尺度上估计电池SOC。最后,在不同SOC初始值、不同温度条件下,对电池SOC的估计结果进行比较和分析,本文所提方法最大绝对误差和平均绝对误差分别为1.05%和0.42%,表明该算法具有较高的精度和较好的鲁棒性。 展开更多
关键词 锂离子电池 荷电状态 多温度 多新息自适应鲁棒无迹卡尔曼滤波
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基于多新息扩展卡尔曼滤波的锂离子电池SOC估计
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作者 吴胜利 欧华 邢文婷 《科学技术与工程》 北大核心 2024年第16期6742-6748,共7页
锂电池具有高能量密度、循环寿命长等优点而被广泛应用于电动汽车动力装置,但车辆运行状况复杂多变,且电池内部呈现高度非线性的性质,导致电池荷电状态(state of charge, SOC)难以准确计算。为优化锂电池SOC估计精度,构建结合Warburg元... 锂电池具有高能量密度、循环寿命长等优点而被广泛应用于电动汽车动力装置,但车辆运行状况复杂多变,且电池内部呈现高度非线性的性质,导致电池荷电状态(state of charge, SOC)难以准确计算。为优化锂电池SOC估计精度,构建结合Warburg元件的分数阶二阶RC模型,采用自适应遗传算法进行参数辨识;融合多新息理论和扩展卡尔曼滤波算法,提出基于多新息扩展卡尔曼滤波(multi innovation extended Kalman filter, MIEKF)的锂离子电池SOC估计算法,并利用试验数据验证该方法的有效性,为提高SOC估计精度和车载锂电池的循环使用寿命提供了新的方法途径和实践支撑。 展开更多
关键词 锂离子电池 分数阶模型 多新息理论 扩展卡尔曼滤波(EKF) 荷电状态(SOC)
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sFLC、血清钙离子在多发性骨髓瘤患者诊断及预后判断中的应用价值
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作者 裴晓杭 张丽娜 +5 位作者 周盼 王同保 连成 张萍 雷平冲 朱尊民 《中国实验血液学杂志》 CAS CSCD 北大核心 2024年第3期794-798,共5页
目的:探讨血清游离轻链(sFLC)、血清钙离子在多发性骨髓瘤(MM)患者诊断及预后中的临床应用价值。方法:选取2018年1月至2022年1月在河南省人民医院治疗的MM患者40例作为观察组,同时选取健康志愿者40例作为对照组,比较两组患者的sFLC-κ、... 目的:探讨血清游离轻链(sFLC)、血清钙离子在多发性骨髓瘤(MM)患者诊断及预后中的临床应用价值。方法:选取2018年1月至2022年1月在河南省人民医院治疗的MM患者40例作为观察组,同时选取健康志愿者40例作为对照组,比较两组患者的sFLC-κ、sFLC-λ、sFLC-κ/λ、血清钙离子等差异性,同时分析观察组不同国际分期系统(ISS)、不同化疗疗效及不同预后患者的sFLC-κ、sFLC-λ、sFLC-κ/λ、血清钙离子等差异性。结果:观察组sFLC-κ水平[(98.39±21.19)对(12.01±4.45)mg/L]、sFLC-λ水平[(210.20±45.54)对(14.10±5.11)mg/L]、低钙血症比例(65%对0)均明显高于对照组(P<0.05),而sFLC-κ/λ比值[(0.44±0.10)对(0.87±0.12)]、血清钙离子[(1.98±0.46)对(2.42±0.40)mmol/L]明显低于对照组(P<0.05)。观察组ISS分期Ⅲ期患者sFLC-κ、sFLC-λ浓度、低钙血症比例和低钙血症病程均明显高于Ⅰ期和Ⅱ期患者(P<0.05),而sFLC-κ/λ、血清钙离子均明显低于Ⅰ期和Ⅱ期患者(P<0.05)。观察组有低钙血症患者sFLC-κ水平[(107.76±21.22)对(94.67±20.11)mg/L]、sFLC-λ水平[(245.54±41.12)对(205.54±50.22)mg/L]明显高于无低钙血症患者(P<0.05),而sFLC-κ/λ比值明显低于无低钙血症患者[(0.42±0.04)对(0.47±0.06);P<0.05]。化疗无效患者sFLC-κ水平[(107.29±20.14)对(91.11±18.92)mg/L]、sFLC-λ水平[(247.98±42.26)对(179.29±39.32)mg/L]明显高于化疗有效患者(P<0.05),而sFLC-κ/λ比值明显低于化疗有效患者[(0.43±0.10)对(0.50±0.09);P<0.05]。sFLC-κ、sFLC-λ、sFLC-κ/λ预测化疗无效的ROC曲线下面积分别为0.803、0.793和0.699,P<0.05。存活和死亡患者的sFLC-κ、sFLC-λ、sFLC-κ/λ、血清钙离子、低钙血症比例和低钙血症病程比较差异无统计学意义(均P>0.05)。结论:sFLC、血清钙离子与MM患者ISS分期有关,sFLC水平在预测MM患者化疗疗效方面有一定应用价值,sFLC与血清钙离子在判断MM患者预后方面暂未发现有应用价值。 展开更多
关键词 血清游离轻链 血清钙离子 多发性骨髓瘤 化疗疗效 预后判断
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一种基于多影响因素的锂离子电池放电内阻动态模型
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作者 巫春玲 宋江鑫 +2 位作者 黄鑫蓉 赵玉冰 孟锦豪 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第2期670-678,共9页
直流内阻(DCR)是衡量电池健康状况的关键指标,在实际应用中对功率状态的估算以及热管理都具有重要意义。锂离子电池放电DCR与环境温度、电池荷电状态(SOC)以及放电倍率(C-rate)等因素有关,为了研究这些因素对电池内阻的影响,本文提出一... 直流内阻(DCR)是衡量电池健康状况的关键指标,在实际应用中对功率状态的估算以及热管理都具有重要意义。锂离子电池放电DCR与环境温度、电池荷电状态(SOC)以及放电倍率(C-rate)等因素有关,为了研究这些因素对电池内阻的影响,本文提出一种基于多影响因素的锂离子电池放电内阻动态模型,利用二元四次多项式对DCR与环境温度和电池SOC进行最小二乘拟合,再将所得二元四次多项式系数与放电倍率进行三次多项式拟合,最终建立DCR与放电倍率、环境温度和SOC之间关系的内阻模型。运用多倍率混合脉冲功率特性(HPPC)实验对锂离子电池进行充放电测试,并根据测试数据对所提出的模型进行验证,实验结果表明,所建立的动态内阻模型获得的DCR估算值与实验值的最大均方根误差为0.9758 mΩ,证明所提出的电池放电内阻模型是有效的。 展开更多
关键词 锂离子电池 HPPC实验 放电直流内阻 多因素内阻模型 多项式拟合
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粤北左坑离子吸附型稀土矿床含矿岩体地球化学特征与稀土元素迁移‒富集机理
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作者 李莎莎 汪礼明 +7 位作者 熊子良 刘东宏 张富铁 刘浏 黄凯 周忠帅 杨胜虎 欧阳志侠 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第2期259-269,I0001-I0004,共15页
广东省新丰县左坑大型稀土矿床为典型的华南离子吸附型矿床,位于佛冈复式岩体的北部,已查明稀土矿石量17152万吨,总稀土氧化物(TREO)资源量约18万吨,离子相稀土氧化物(SREO)资源量约11万吨。对该矿床成矿母岩黑云母花岗岩进行主量和稀... 广东省新丰县左坑大型稀土矿床为典型的华南离子吸附型矿床,位于佛冈复式岩体的北部,已查明稀土矿石量17152万吨,总稀土氧化物(TREO)资源量约18万吨,离子相稀土氧化物(SREO)资源量约11万吨。对该矿床成矿母岩黑云母花岗岩进行主量和稀土元素分析发现,其岩石性质和地球化学特征与佛冈花岗岩主体类似,同属于高硅、富碱、贫钙镁的铝质A型花岗岩。对6个钻孔的SREO含量、TREO含量、离子相稀土氧化物析出率、地理位置、成矿母岩稀土含量等信息进行对比研究后发现:①基岩稀土含量相似的情况下,产出于山顶的矿体上方风化壳厚度越大,形成矿体所需要的离子相稀土氧化物析出率越小;②稀土元素在成矿母岩浆中完成初始富集后,进而在风化过程中完成二次富集,还可能在剥蚀过程中随地表水下渗迁移至风化壳中渗透系数更小的位置完成第三次富集。因此,在离子吸附型稀土矿床中影响稀土元素垂向分布模式的因素除了风化壳中水体pH值和水化学类型外,还需考虑静水面与矿体的相对位置和渗透系数的共同作用。 展开更多
关键词 离子吸附型稀土矿床 稀土元素 离子相析出率 富集倍数 静水面 渗透系数
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GC-MS/MS法测定阿加曲班中基因毒性杂质NDMA和NDEA
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作者 季行行 刘芹 +3 位作者 邱荣英 李铁健 李观军 张贵民 《中南药学》 CAS 2024年第5期1354-1357,共4页
目的 采用GC-MS/MS法建立一种同时测定阿加曲班中N-亚硝基二甲胺(NDMA)和N-亚硝基二乙胺(NDEA)含量的方法。方法 以Agilent DB-WAX UI(30 m×0.25 mm×0.25 μm)气相色谱柱分离,离子源为电子轰击电离源(EI),在多反应离子监测(M... 目的 采用GC-MS/MS法建立一种同时测定阿加曲班中N-亚硝基二甲胺(NDMA)和N-亚硝基二乙胺(NDEA)含量的方法。方法 以Agilent DB-WAX UI(30 m×0.25 mm×0.25 μm)气相色谱柱分离,离子源为电子轰击电离源(EI),在多反应离子监测(MRM)模式下检测,按外标法建立标准曲线测定阿加曲班中两种杂质的含量。结果 NDMA和NDEA分别在19.20~128.00 ng·mL^(-1)和5.36~35.73 ng·mL^(-1)与峰面积线性关系良好;NDMA和NDEA的定量限分别为19.20 ng·mL^(-1)和5.36 ng·mL^(-1),检测限分别为6.40 ng·mL^(-1)和1.79 ng·mL^(-1)。NDMA和NDEA低、中、高浓度的平均回收率分别为110.2%、107.8%、107.2%(RSD为3.2%,n=3)和114.7%、107.3%、107.6%(RSD为5.6%,n=3)。结论 该方法操作简单,能够有效测定阿加曲班中NDMA和NDEA的含量。 展开更多
关键词 阿加曲班 GC-MS/MS法 N-亚硝基二甲胺 N-亚硝基二乙胺 多反应离子监测
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Could non-invasive brain-stimulation prevent neuronal degeneration upon ion channel re-distribution and ion accumulation after demyelination? 被引量:3
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作者 Friederike Pfeiffer Alia Benali 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第11期1977-1980,共4页
Fast and efficient transmission of electrical signals in the nervous system is mediated through myelinated nerve fibers.In neuronal diseases such as multiple sclerosis,the conduction properties of axons are disturbed ... Fast and efficient transmission of electrical signals in the nervous system is mediated through myelinated nerve fibers.In neuronal diseases such as multiple sclerosis,the conduction properties of axons are disturbed by the removal of the myelin sheath,leaving nerve cells at a higher risk of degenerating.In some cases,the protective myelin sheath of axons can be rebuilt by remyelination through oligodendroglial cells.In any case,however,changes in the ion channel organization occur and may help to restore impulse conduction after demyelination.On the other hand,changes in ion channel distribution may increase the energy demand of axons,thereby increasing the probability of axonal degeneration.Many attempts have been made or discussed in recent years to increase remyelination of affected axons in demyelinating diseases such as multiple sclerosis.These approaches range from pharmacological treatments that reduce inflammatory processes or block ion channels to the modulation of neuronal activity through electrical cortical stimulation.However,these treatments either affect the entire organism(pharmacological)or exert a very local effect(electrodes).Current results show that neuronal activity is a strong regulator of oligodendroglial development.To bridge the gap between global and very local treatments,non-invasive transcranial magnetic stimulation could be considered.Transcranial magnetic stimulation is externally applied to brain areas and experiments with repetitive transcranial magnetic stimulation show that the neuronal activity can be modulated depending on the stimulation parameters in both humans and animals.In this review,we discuss the possibilities of influencing ion channel distribution and increasing neuronal activity by transcranial magnetic stimulation as well as the effect of this modulation on oligodendroglial cells and their capacity to remyelinate previously demyelinated axons.Although the physiological mechanisms underlying the effects of transcranial magnetic stimulation clearly need further investigations,repetitive transcranial magnetic stimulation may be a promising approach for non-invasive neuronal modulation aiming at enhancing remyelination and thus reducing neurodegeneration. 展开更多
关键词 ion channel multiple sclerosis neuronal activity OLIGODENDROCYTE (re-)myelination repetitive TRANSCRANIAL MAGNETIC STIMULATion TRANSCRANIAL MAGNETIC STIMULATion
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Heavy ion‑induced MCUs in 28nm SRAM‑based FPGAs:upset proportions,classifications,and pattern shapes 被引量:1
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作者 Shuai Gao Xin‑Yu Li +7 位作者 Shi‑Wei Zhao Ze He Bing Ye Li Cai You‑Mei Sun Guo‑Qing Xiao Chang Cai Jie Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第12期128-137,共10页
For modern scaling devices,multiple cell upsets(MCUs)have become a major threat to high-reliability field-programmable gate array(FPGA)-based systems.Thus,both performing the worst-case irradiation tests to provide th... For modern scaling devices,multiple cell upsets(MCUs)have become a major threat to high-reliability field-programmable gate array(FPGA)-based systems.Thus,both performing the worst-case irradiation tests to provide the actual MCU response of devices and proposing an effective MCU distinction method are urgently needed.In this study,high-and medium-energy heavy-ion irradiations for the configuration random-access memory of 28 nm FPGAs are performed.An MCU extraction method supported by theoretical predictions is proposed to study the MCU sizes,shapes,and frequencies in detail.Based on the extraction method,the different percentages,and orientations of the large MCUs in both the azimuth and zenith directions determine the worse irradiation response of the FPGAs.The extracted largest 9-bit MCUs indicate that high-energy heavy ions can induce more severe failures than medium-energy ones.The results show that both the use of high-energy heavy ions during MCU evaluations and effective protection for the application of high-density 28 nm FPGAs in space are extremely necessary. 展开更多
关键词 FPGAS Heavy ions multiple cell upsets Extraction Worse irradiation
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Studies of K-shell x-ray energy shifts induced by MeV/u heavy ions
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作者 宋张勇 杨治虎 +8 位作者 邵剑雄 崔莹 张红强 阮芳芳 杜鹃 高志民 于得洋 陈熙萌 蔡晓红 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1443-1450,共8页
This paper reports that the K x-ray spectra of the thin target 4TAg, 4sCd, 49In and 50Sn were measured by an HPGe semi-conductor detector in collisions with 84.5 MeV 6C4+ ions. Our experiment revealed the Kα x-ray e... This paper reports that the K x-ray spectra of the thin target 4TAg, 4sCd, 49In and 50Sn were measured by an HPGe semi-conductor detector in collisions with 84.5 MeV 6C4+ ions. Our experiment revealed the Kα x-ray energy shifts were not obvious and the Kβ1 x-ray energy shifts were about 90-110 eV. The simple model of Burch et al has been previously used to calculate the K x-ray energy shifts due to an additional vacancy in 2p orbit. The present work extends the model of Burch to calculate the x-ray energy shifts of multiple ionized atoms induced by heavy ions with kinetic energy of MeV/u. In addition to our experimental results, many other experimental results are compared with the calculated values by using the model. 展开更多
关键词 K-shell x-ray energy shifts heavy ion collisions multiple ionization
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Nd L-shell x-ray emission induced by light ions
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作者 Xian-Ming Zhou Jing Wei +8 位作者 Rui Cheng Yan-Hong Chen Ce-Xiang Mei Li-Xia Zeng Yu Liu Yan-Ning Zhang Chang-Hui Liang Yong-Tao Zhao Xiao-An Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期310-315,共6页
The L-shell x-ray of Nd has been obtained for 300-600 keV He2+ions impacting,and compared with that produced by H+and H2+ions.The threshold of projectile kinetic energy for L-shell ionization of Nd is crudely verified... The L-shell x-ray of Nd has been obtained for 300-600 keV He2+ions impacting,and compared with that produced by H+and H2+ions.The threshold of projectile kinetic energy for L-shell ionization of Nd is crudely verified in the energy region of about 300-400 keV.It is found that the energy of the distinct L-subshell x-rays has a blue shift.The relative intensity ratios of Lβ_(1,3,4)and Lβ_(2,15)to Lα_(1,2)x-ray are enlarged compared to the atomic data,and they decrease with the increase of the incident energy,and increase with increasing the effective nuclear charge of the incident ions.That is interpreted by the multiple ionization of outer-shells induced by light ions. 展开更多
关键词 light ions ion-atom collision L-shell x-ray multiple ionization
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