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Synthesis and Characteristic Study on Complexes of Europium(Ⅲ) and Maleic Acid Doped with Non-Fluorescent Ions 被引量:2
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作者 沈庆月 陆春华 +2 位作者 倪亚茹 吉庆 许仲梓 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第5期549-553,共5页
Complex of europium (Ⅲ) with maleic acid, and binuclear complexes of europium(Ⅲ)with maleic acid doped with non-fluorescent ions gadolinium, lanthanum and yttrium, were synthesized. The compositions and structur... Complex of europium (Ⅲ) with maleic acid, and binuclear complexes of europium(Ⅲ)with maleic acid doped with non-fluorescent ions gadolinium, lanthanum and yttrium, were synthesized. The compositions and structures of complexes were characterized with elemental analysis, single crystal X-ray diffraction, IR and DSC-TG. Fluorescent properties were studied with fluorescence spectrum. The results indicated that the strongest fluorescent complexes were obtained when the ratio of europium and non-fluorescent ion was 8:2. The order of Eu^3+ fluorescence strengthened by three doped rare earths was Gd^3+ 〉La^3+ 〉Y^3+ 展开更多
关键词 EUROPIUM non-fluorescent ion maleic acid crystal structure fluorescence spectrum rare earths
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Non-Linear Ion-Acoustic Solitary Waves in Electron-Positron-Ion Plasma with Non-Thermal Electrons 被引量:1
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作者 S. K. Anguma I. Habumugisha +2 位作者 L. Nazziwa E. Jurua N. Noreen 《Journal of Modern Physics》 2017年第6期892-902,共11页
Ion-acoustic solitary (IAS) waves in electron-positron-ion (e-p-i) plasma have been of interest to many researchers probably due to their relevance in understanding the Universe. However, the study of non-linear ion-a... Ion-acoustic solitary (IAS) waves in electron-positron-ion (e-p-i) plasma have been of interest to many researchers probably due to their relevance in understanding the Universe. However, the study of non-linear ion-acoustic waves in e-p-i plasma with non-thermal electrons has not been adequately studied. A theoretical investigation on non-linear IAS waves in e-p-i plasma comprising of warm inertial adiabatic fluid ions and electrons that are kappa distributed, and Boltzman distributed positron is presented here using the Sagdeev potential technique. It was found that existence domains of finite amplitude IAS waves were confined within the limits of minimum and maximum Mach numbers with varying k values. For lower values of k, the amplitude of the solitary electrostatic potential structures increased as the width decreased, while for high values, the potential amplitude decreased as the width of the solitary structure increased. 展开更多
关键词 non-THERMAL ELECTRONS ion-Acoustic Solitary Waves Electron-Positron-ion Plasmas
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The concentration variation features of sea salt ions and non sea salt ions in a firn core recovered from Princess Elizabeth Land, East Antarctica
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作者 张明军 任贾文 +2 位作者 效存德 李忠勤 秦大河 《Chinese Journal of Polar Science》 2004年第2期85-90,共6页
A 51.85 m firn core drilled in Princess Elizabeth Land, Antarctica, during the 1996-1997 Chinese First Antarctic Inland Expedition, has been measured for δ 18 O and major ions. Based on the high quality data ... A 51.85 m firn core drilled in Princess Elizabeth Land, Antarctica, during the 1996-1997 Chinese First Antarctic Inland Expedition, has been measured for δ 18 O and major ions. Based on the high quality data of the seasonal variations of major ions, the firn core was dated with errors within ±3 years. The 51.85 m firn core record extends for 251 years (A. D. 1745-1996). The results of the glaciochemistry data of the firn core show that the mean concentrations of Cl -, Na + and Mg 2+ are similar to those reported from other coastal areas in East Antarctica. However, mean concentrations of Ca 2+ are much higher than those reported from other regions, this anomaly phenomenon may be related to the strong local terrestrial sources. It is found that the variations of three kinds of sea salt ions (Cl -, Na + and Mg 2+ ) in the past 150 years show very similarly rising trends, which may be the results the Southern Hemisphere warming in the past century. 展开更多
关键词 ANTARCTICA firn core sea salt ion and non sea salt ion.
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Relative Deficiency of Intracellular Potassium in Relation to the Functional Changes and Diseases in Non-Nervous System 被引量:2
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作者 Jiapei Dai 《Natural Science》 CAS 2022年第11期497-502,共6页
Because of the huge differences in cellular structures and functions in non-nervous system and interaction between the nervous and non-nervous systems in potassium ion absorption, storage and effective utilization, th... Because of the huge differences in cellular structures and functions in non-nervous system and interaction between the nervous and non-nervous systems in potassium ion absorption, storage and effective utilization, the organs, tissues and tissue cells in non-nervous system have different functional dependence on potassium ion and its characteristics in competitive distribution differences. Therefore, I propose that the relative deficiency of potassium in cells in non-nervous organs and tissues may show very different functional changes and disease characteristics. Some are susceptible to pathogenic microorganisms, some may result in decrease of cell functions, and other may have comprehensive changes such as chronic inflammation. Therefore, the core causes for the functional changes and lesions of these non-nervous organs and tissues are closely related to the relative deficiency of potassium ions in their cells, which provides important ideas for the prevention and treatment of these functional changes and diseases. 展开更多
关键词 Potassium ion Relative Deficiency of Potassium ions Na+ K+-ATPase non-Nervous Diseases Quantum Biology
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Non-equilibrium ignition criterion for magnetized deuterium–tritium fuel 被引量:1
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作者 E.Ghorbanpour A.Ghasemizad S.Khoshbinfar 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第4期132-142,共11页
In this paper, non-equilibrium ignition conditions for magnetized cylindrical deuterium–tritium plasma in the presence of an axial magnetic field have been investigated. It is expected that temperature imbalance betw... In this paper, non-equilibrium ignition conditions for magnetized cylindrical deuterium–tritium plasma in the presence of an axial magnetic field have been investigated. It is expected that temperature imbalance between ions and electrons as well as the axial magnetic field will relax the threshold of ignition conditions.Therefore, ignition conditions for this model are derived numerically involving the energy balance equation at the stagnation point. It has been derived using parametric space including electron and ion temperature(T_e, T_i), areal density(q R), and seed magnetic field-dependent free parameters of B/q, mB, and BR. For B/ρ < 10~6 G cm^3 g^(-1),mB < 4 × 10~4 G cm g^(-1), and BR <3 × 10~5 G cm, the minimum fuel areal density exceeds between ρR >0.002 g cm^(-2), ρR> 0.25 g cm^(-2), and ρR > 0.02 g cm^(-2),respectively. The practical equilibrium conditions also addressed which is in good agreement with the corresponding one-temperature magnetized mode proposed in previous studies. Moreover, it has been shown that the typical criterion of BR ≥(6.13–4.64) × 10~5 G cm would be expectable. It is also confirmed that the minimum product of areal density times fuel temperature in equilibrium model is located in the range of T = 6–8 keV for all these free parameters, depending on the magnitude of the magnetic field. This is the entry point for the non-equilibrium model consistent with equilibrium model. 展开更多
关键词 MAGNETIZED plasma Two-temperature model ion-electron non-EQUILIBRIUM AXIAL magnetic field IGNITion criteria
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A Simple and Rapid Method for the Detection of Non-Ionic Surfactants 被引量:1
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作者 Minori Kamaya Hikaru Sugimoto Yosuke Yamaguchi 《American Journal of Analytical Chemistry》 2014年第16期1121-1128,共8页
A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs a... A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs adhesion of the ion-association of potassium/non-ionic surfactants complex and tetraphenylporphyrin tetrasulfonic acid obtained by vigorous shaking. The adhered ion-associate was dissolved with water and its absorbance was measured. The sensitivity for Triton X-100 was determined to be 0.146 (expressed as absorbance of 1 mg/L solution). The adhesion tendency of ion-associate was found to be dependent on the water contact angle, which in turn was influenced by a high adhesion of the ion-associate and by low blank values. In this respect, a tetrafluo-roethylene vessel was found to be the most suitable for the detection of non-ionic surfactants. This spectrophotometrical method is simply and rapidly performed by a procedure based on mechanical shaking and can be employed to detect non-ionic surfactants containing more than 7 polyethylene oxide units. 展开更多
关键词 non-ionIC SURFACTANT DETECTion SPECTROPHOTOMETRY TETRAPHENYLPORPHYRIN Tetrasulfonic Acid ion-Associate Adhesion Potassium/non-ionic SURFACTANT Complex
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Pt Deposition on Anode Enhances the Performance of Dye-Sensitized Solar Cell with Non-Cross-Linked Gel Electrolyte 被引量:2
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作者 Masato Ohmukai Jun Kyokane 《Journal of Materials Science and Chemical Engineering》 2013年第6期16-19,共4页
We fabricated dye-sensitized solar cells with non-cross-linked fluorinated gel electrolyte. The application of fluorinated gel to electrolyte is a challenging issue at present. The gelation of the electrolyte is of im... We fabricated dye-sensitized solar cells with non-cross-linked fluorinated gel electrolyte. The application of fluorinated gel to electrolyte is a challenging issue at present. The gelation of the electrolyte is of importance in order to solve the problem in the durability of the cell. We investigated, in this article, the effect of Pt deposition on the anode of the cell. The Pt was deposited by means of a DC sputtering technique. The studies showed that the deposition time strongly affected both open voltage and short-circuit current of the cell. The adaptive thickness of the Pt layer was determined to be 10 nm for the non-cross-linked fluorinated gel electrolyte cells. 展开更多
关键词 RUTHENIUM ion Complex DYE-SENSITIZED Solar Cell non-Cross-Linked FLUORINATED Gel Electrolyte PT Layer DC Sputtering DEPOSITion
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Wetting behavior and reaction mechanism of non-corrosive flux on aluminum
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作者 俞伟元 郭熠 +2 位作者 刘赟 顾海龙 袁文栋 《China Welding》 EI CAS 2015年第4期27-32,共6页
The energy-dispersive spectroscopy ( EDS ) , X-ray diffraction analysis ( XRD ) and differential thermal analysis (DTA) were used to analyze the melting, spreading process, and reaction mechanism of non-corrosiv... The energy-dispersive spectroscopy ( EDS ) , X-ray diffraction analysis ( XRD ) and differential thermal analysis (DTA) were used to analyze the melting, spreading process, and reaction mechanism of non-corrosive flux on the surface of aluminum. The result indicates that the whole process can be divided into three stages. In the first stage, flux is heated from room temperature to its melting point, which is called the endothermic stage, mainly absorbs heat and generates a small amount of liquid flux. When the temperature exceeds the melting point of flux, a large amount of liquid flux is generated and reacts with oxide films on the surface of aluminum. This stage is called the reaction stage. The third stage is a spreading and cleaning process, in which residues and reaction products quickly flow out from the center with liquid flux. The different compositions of flux perform different functions in brazing. K3AlF6 can remove oxide film us a cleaner. Only in liquid or molten state can flux remove oxide film on the substrate. 展开更多
关键词 non-corrosive flux brazing behavior reaction mechanism ion state
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Dust Acoustic Compressive Waves in a Warm Dusty Plasma Having Non-Thermal Ions and Non-Isothermal Electrons
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作者 Apul N.DEV Manoj K.DEKA +1 位作者 Rajesh SUBEDI Jnanjyoti SARMA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第9期721-727,共7页
In this article an investigation is presented on the properties of dust acoustic(DA)compressive solitary wave propagation in an adiabatic dusty plasma,including the effect of nonthermal positive and negative ions an... In this article an investigation is presented on the properties of dust acoustic(DA)compressive solitary wave propagation in an adiabatic dusty plasma,including the effect of nonthermal positive and negative ions and non-isothermal electrons.The reductive perturbation method has been employed to derive the lower degree modified Kadomtsev-Petviashivili(mK-P),3D Schamel-Korteweg-de-Vries equation or modified Kadomtsev-Petviashivili(mK-P) equations for dust acoustic solitary waves in a homogeneous,unmagnetized and collisionless plasma whose constituents are non-isothermal electrons,singly charged positive and negative non-thermal ions and massive charged dust particles.The stationary analytical solutions of the lower degree mK-P and mK-P equations are numerically analyzed,where the effect of various dusty plasma constituents on DA solitary wave propagation is taken into account.It is observed that both the ions in dusty plasma play a key role in the formation of DA compressive solitary waves,and also the ion concentration and non-isothermal electrons control the transformation of the compressive potentials of the waves. 展开更多
关键词 dusty plasma reductive perturbation method non-isothermal ions compressive solitary wave
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Analysis of trace elements in air particulate matters by non-suppressed ion chromatography
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作者 Feng Yingsheng(Y.S.Fung) and Tan Weiming (W.M.Tam)Department of Chemistry,Hong Kong University,Hong Kong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1991年第1期29-39,共11页
The application of non-suppressed ion chromatography for monitoring of trace elements in air particulate matter was studied in the present investigation. The results indicate that the use of microwave acid digestion m... The application of non-suppressed ion chromatography for monitoring of trace elements in air particulate matter was studied in the present investigation. The results indicate that the use of microwave acid digestion method is superior in comparison with the conventional thermal acid digestion method as it leads to higher recovery, better reproducibility, lower volatility loss, better protection against environmental contamination and much less digestion time (5 minutes vs. 24 hours). The use of eluent as extractant is shown to reduce the water dip problem in the chro-matogram. The addition of chelating agent in the eluent coupled with UV detection is shown to provide satisfactory chromatographic separation and good sensitivity for the analysis of transition metals present in the air particulate matter. Using the U.S. National Bureau of Standards Reference Material 1648 Urban Particulate Matter as standard for checking, the analytical procedure is shown to give good recovery and reproducibility for the detection of the following cations and anions in air particulate matter: Fe2 Cu, Mn, Pb, Zn, Mg, Na, HN4+, Cl-, NO3- and SO42-. Field test was also performed to check the applicability of the method and the results obtained were discussed in the present paper. 展开更多
关键词 non-suppressed ion chromatography air particulate matter trace metals analysis anions analysis microwave digestion.
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Non-Uniformity of Heavy-Ion Beam Irradiation on a Direct-Driven Pellet in Inertial Confinement Fusion
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作者 Leila GHOLAMZADEH Abbas GHASEMIZAD 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第1期44-49,共6页
Heavy-ion-driven fusion (HIF) is a scheme to achieve inertial confinement fusion (ICF). Investigation of the non-uniformity of heavy-ion beam (HIB) irradiation is one of the key issues for ICF driven by powerful... Heavy-ion-driven fusion (HIF) is a scheme to achieve inertial confinement fusion (ICF). Investigation of the non-uniformity of heavy-ion beam (HIB) irradiation is one of the key issues for ICF driven by powerful heavy-ion beams. Ions in HIB impinge on the pellet surface and deposit their energy in a relatively deep and wide area. Therefore, the non-uniformity of HIB irradiation should be evaluated in the volume of the deposition area in the absorber layer. By using the OK1 code with some corrections, the non-uniformity of heavy-ion beam irradiation for the different ion beams on two kinds of targets were evaluated in 12-beam, 20-beam, 60-beam and 120-beam irradiation schemes. The root-mean-square (RMS) non-uniformity value becomes aRMS = 8.39% in an aluminum mono-layer pellet structure and aRMS = 6.53% in a lead-aluminum layer target for the 12-uranium-beam system. The RMS non-uniformity for the lead-aluminum layer target was lower than that for the mono-layer target. The RMS and peak-to-valley (PTV) non-uniformities are reduced with the increase in beam number, and low at the Bragg peak layer. 展开更多
关键词 heavy ion beam deposition energy irradiation non-uniformity inertial con- finement fusion Bragg peak layer
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On Basic Parameters and Radiation Theory of Non-Uniform Channel DMOS
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作者 LIZe-hong 《Journal of Electronic Science and Technology of China》 2005年第1期91-92,共2页
关键词 non-uniform channel DMOS basic parameter total ion dose single ion radiation transient response
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不同放电倍率下软包锂离子电池非均匀生热表征方法
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作者 刘素贞 张涛 +2 位作者 张闯 徐志成 金亮 《电源技术》 CAS 北大核心 2024年第6期1095-1102,共8页
软包锂离子电池非均匀的温度分布严重影响其循环性能、使用寿命和安全性。针对软包锂离子电池生热的建模表征复杂且精度不高的问题,提出了一种基于生热分布因子的软包锂离子电池非均匀生热表征方法。将电池划分成不同区域,并将生热分布... 软包锂离子电池非均匀的温度分布严重影响其循环性能、使用寿命和安全性。针对软包锂离子电池生热的建模表征复杂且精度不高的问题,提出了一种基于生热分布因子的软包锂离子电池非均匀生热表征方法。将电池划分成不同区域,并将生热分布因子引入Bernardi生热公式中获取不同区域的生热率;通过传热和优化数值模拟求解电池的温度分布,同时辨识不同区域的生热分布因子,分析了软包电池生热非均匀分布特性;采用三次样条差值法推导了生热分布因子与放电倍率的对应关系,研究了不同放电倍率下生热分布因子的演化规律。实验结果表明,该方法所建立的热模型在2.75 C和3.75 C下的温度估计值的平均绝对百分比误差最大不超过1.55%,该方法能够准确估计电池非均匀的生热率,并实现电池温度分布特性的有效表征。 展开更多
关键词 软包锂离子电池 非均匀生热 生热分布因子 放电倍率
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低温等离子体耦合Fe^(2+)均相催化降解甲苯和丙酮 被引量:1
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作者 刘蓉蓉 秦彩虹 +2 位作者 姜超超 黄家玉 张鹏 《中国环境科学》 EI CAS CSCD 北大核心 2024年第2期670-678,共9页
本文对比研究了两类典型VOCs(甲苯和丙酮)在单独NTP、NTP+LC/Fe^(2+)和NTP+LC/Fe^(2+)+PCA系统的降解效果.结果表明,甲苯和丙酮的去除率均随放电电压的升高而升高;在相同电压下,甲苯降解效率高于丙酮,但降解过程中O_(3)的产生量相当;当... 本文对比研究了两类典型VOCs(甲苯和丙酮)在单独NTP、NTP+LC/Fe^(2+)和NTP+LC/Fe^(2+)+PCA系统的降解效果.结果表明,甲苯和丙酮的去除率均随放电电压的升高而升高;在相同电压下,甲苯降解效率高于丙酮,但降解过程中O_(3)的产生量相当;当放电电压为22kV时,NTP+LC/Fe^(2+)+PCA系统的甲苯去除效率比单独NTP提高了18.2%,丙酮的去除效率提高了55.5%;NTP+LC/Fe^(2+)+PCA的O_(3)去除率可达100%;EPR和猝灭实验表明,羟基自由基和超氧自由基在LC/Fe^(2+)+PCA反应器中对VOCs去除有重要贡献.最后,结合测定的自由基和中间有机产物,推测了VOCs在NTP+LC/Fe^(2+)体系中的降解途径. 展开更多
关键词 甲苯 丙酮 低温等离子体 均相催化 亚铁离子
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三水铝石和勃姆石吸附行为的研究进展
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作者 周宗可 覃宗华 +3 位作者 万泉 聂信 于文彬 杨淑勤 《硅酸盐通报》 CAS 北大核心 2024年第3期878-890,共13页
三水铝石和勃姆石不仅是在土壤和水环境中分布广泛的铝氢氧化物矿物,也是重要的工业原料与产品。它们与环境中无机非金属离子、无机金属离子及有机物的吸附作用极大地影响着地表环境中物质的迁移富集和环境污染物的吸附去除,并且由于结... 三水铝石和勃姆石不仅是在土壤和水环境中分布广泛的铝氢氧化物矿物,也是重要的工业原料与产品。它们与环境中无机非金属离子、无机金属离子及有机物的吸附作用极大地影响着地表环境中物质的迁移富集和环境污染物的吸附去除,并且由于结构特性和表面性质,三水铝石和勃姆石在研究高效经济的吸附剂方面也具有较为重要的应用。本文在概述三水铝石和勃姆石结构和表面物理化学性质的基础上,对三水铝石和勃姆石表面多种非金属离子、金属离子和有机物的吸附行为进行综述,期望加深对铝氢氧化物矿物在地表环境物质循环中所起作用的理解,以及拓展其工业应用。 展开更多
关键词 三水铝石 勃姆石 铝氢氧化物 吸附 非金属离子 金属离子
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红光联合银离子敷料治疗慢性难愈合创面的最佳方案筛选及机制 被引量:1
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作者 卢洁 金杰 +2 位作者 于俪超 马莎莎 许红梅 《中国组织工程研究》 CAS 北大核心 2024年第10期1554-1561,共8页
背景:临床上多采用红光照射和银离子敷料治疗慢性难愈合创面,但是红光照射联合银离子敷料治疗慢性难愈合创面的最佳照射时间和不同银离子敷料的组合尚未确定。目的:探讨红光联合银离子敷料治疗大鼠慢性难愈合创面的最佳照射时间与敷料... 背景:临床上多采用红光照射和银离子敷料治疗慢性难愈合创面,但是红光照射联合银离子敷料治疗慢性难愈合创面的最佳照射时间和不同银离子敷料的组合尚未确定。目的:探讨红光联合银离子敷料治疗大鼠慢性难愈合创面的最佳照射时间与敷料组合。方法:取SD大鼠,采用全层皮肤缺损+创面涂抹金黄色葡萄球菌+皮下注射氢化可的松的方式制作慢性难愈合创面模型。采用随机数字表法将造模成功的72只大鼠随机分为4组,每组18只:在创面标准换药的基础上分别给予红光照射20 min+脂质水胶体硫酸银敷料覆盖(A1B1组)、红光照射20 min+藻酸钙纤维银敷料覆盖(A1B2组)、红光照射30 min+脂质水胶体硫酸银敷料覆盖(A2B1组)、红光照射30 min+藻酸钙银纤维敷料覆盖(A2B2组),每24 h换药、照射一次并更换敷料。连续治疗14 d后,检测各组大鼠创面愈合率、细菌菌落数、炎症反应、组织形态学及血管新生情况。结果与结论:①随着治疗时间的延长,4组大鼠创面愈合率增加,A2B2组大鼠治疗后3,7,14 d的创面愈合率高于其他3组(P<0.05);②治疗后第7天的创面细菌培养结果显示,A2B2组细菌菌落数低于其他3组(P<0.05);Western-blotting检测显示,随着治疗时间的延长,4组大鼠创面组织中肿瘤坏死因子α、白细胞介素6的蛋白表达均下降,白细胞介素10的蛋白表达均升高,A2B2组肿瘤坏死因子α、白细胞介素6的蛋白表达低于其他3组(P<0.05),白细胞介素10的蛋白表达高于其他3组(P<0.05);③治疗后第14天的创面苏木精-伊红染色显示,A2B2组可见大量的胶原纤维平行分布且连接最紧密,明显优于其他3组;④治疗后第7天的创面免疫荧光染色显示,A2B2组CD31荧光强度表达高于其他3组(P<0.05);治疗后3,7,14 d的q-PCR检测显示,A2B2组血管内皮生长因子a、血管内皮生长因子受体2的mRNA表达均高于其他3组(P<0.05);治疗后3,7,14 d的Western-blotting检测显示,A2B2组血管内皮生长因子a、血管内皮生长因子受体2的蛋白表达均高于其他3组(P<0.05);⑤结果表明,红光照射30 min联合藻酸钙银纤维敷料治疗慢性难愈合创面的效果更优。 展开更多
关键词 红光 银离子敷料 析因设计 慢性难愈合创面 K值 血管生成 交互作用 血管内皮生长因子
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不同侵蚀环境下水下不分散混凝土抗Cl-和SO_(4)^(2-)渗透性能研究
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作者 于泽 艾红梅 +2 位作者 王万里 王宝民 韩俊楠 《混凝土》 CAS 北大核心 2024年第3期61-67,共7页
在不同侵蚀环境中的水下不分散混凝土会受到侵蚀离子的渗透,严重影响水下不分散混凝土的耐久性能。研究了不同强度等级的水下不分散混凝土在氯盐溶液、硫酸盐溶液和复合盐溶液3种侵蚀环境下抵抗侵蚀离子渗透的能力。通过分析不同矿渣掺... 在不同侵蚀环境中的水下不分散混凝土会受到侵蚀离子的渗透,严重影响水下不分散混凝土的耐久性能。研究了不同强度等级的水下不分散混凝土在氯盐溶液、硫酸盐溶液和复合盐溶液3种侵蚀环境下抵抗侵蚀离子渗透的能力。通过分析不同矿渣掺量下抗侵蚀离子渗透性能的影响,探究Cl^(-)和SO_(4)^(2-)在渗透过程中的耦合作用,并利用AutoPoreIV9500压汞仪测试不同侵蚀龄期各试样的孔隙特征。结果表明:在距离侵蚀表面5 mm和30 mm处,C35混凝土比C25混凝土的离子浓度降低7%~60%;在相同侵蚀环境下,掺入矿渣粉可以显著减小水下不分散混凝土中侵蚀离子浓度;水下不分散混凝土中的孔隙组成以直径小于50 nm的介孔和微孔为主,矿渣的掺入细化了孔隙结构。即水下不分散混凝土的抗渗性能随着其抗压强度等级的提高而显著提高,并且矿渣粉的掺入使结构更加致密,从而有效提高混凝土抗Cl^(-)和SO_(4)^(2-)渗透性能。 展开更多
关键词 水下不分散混凝土 矿渣粉 抗侵蚀离子渗透 孔结构
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生物活性离子改性透钙磷石骨水泥的生物和理化性能
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作者 曾诚 于欢欢 +3 位作者 龚玉康 王晨浩 张印恩 高文山 《中国组织工程研究》 CAS 北大核心 2024年第22期3561-3568,共8页
背景:透钙磷石骨水泥作为一种骨替代和骨填充材料,因其具有良好的生物相容性、骨传导性等优点,尤其是相比于其他磷酸钙类骨水泥具有更好的生物降解能力,在骨修复方面有重要应用价值,但也因其存在机械性能不足、固化反应快及注射性能差... 背景:透钙磷石骨水泥作为一种骨替代和骨填充材料,因其具有良好的生物相容性、骨传导性等优点,尤其是相比于其他磷酸钙类骨水泥具有更好的生物降解能力,在骨修复方面有重要应用价值,但也因其存在机械性能不足、固化反应快及注射性能差等问题的限制,目前一般只能用于非负重区骨的修复。目的:探讨生物活性离子(金属离子和非金属离子)改性透钙磷石骨水泥,以期拓展使用范围。方法:利用Pub Med、Science Direct和中国知网、万方数据库检索2018-2023年发表的文献,中文检索词为“金属离子,铁,铜,锶,镁,锌,非金属离子,改性,骨,透钙磷石骨水泥”;英文检索词为“metal ion,iron,Fe,copper,Cu,strontium,Sr,magnesium,Mg,zinc,Zn,non-metal ion,modification,bone,Brushite Cements”。通过阅读标题、摘要对所得文献进行初筛,排除重复及内容不相关文献,最终纳入64篇文献进行综述。结果与结论:(1)生物活性离子影响透钙磷石骨水泥水化反应过程,不同离子以离子取代的方式掺入透钙磷石骨水泥晶体结构中,改变了骨水泥晶体形态,引起凝固时间、注射性、抗压强度等理化性能改变。(2)离子改性的透钙磷石骨水泥因不同的晶体结构而产生不同的离子释放效应,不同类型离子具有如促血管生成/成骨、抗菌及抗肿瘤等特性而发挥作用,此外,透钙磷石骨水泥具有良好的生物降解性,这对于各离子性能的发挥具有极大优势。(3)不同离子改性透钙磷石骨水泥理化性能影响如下:铁、铜、锶、镁、锌、银、钴可延长凝固时间;锶、镁可提高注射性能;铜、锶、镁、银、硅可增强抗压强度;能同时改善透钙磷石骨水泥以上3种理化性能的离子有锶、镁;良好的理化性能是临床应用的前提,故离子改善透钙磷石骨水泥的凝固时间、注射性及抗压强度等性能对骨水泥的研究应用具有重要意义。(4)不同离子改性透钙磷石骨水泥生物性能影响如下:铜、锶、镁、锌、钴、锂、硅、硒具有促血管生成/成骨效应;铁、铜、镁、锌、银具有抗菌特性;镁离子具有抗炎特性;铜、硒具有抗肿瘤性。(5)综上所述,镁离子能改善透钙磷石骨水泥凝固时间、注射性和抗压强度,同时具有促新生血管生成/成骨及抗菌性,对合并感染的骨缺损治疗具有良好应用前景;此外,铜还具有抗肿瘤特性,因此铜离子在感染、肿瘤引起的骨缺损治疗方面有巨大潜力;只是目前相关研究仍处于基础研究阶段,不同离子掺杂浓度和合成条件等对透钙磷石骨水泥理化性能的影响需进一步探索,同时对于生物性能影响也需更长期的研究观察。 展开更多
关键词 金属离子 非金属离子 改性 透钙磷石骨水泥
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钾离子电池低温电解质的研究进展
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作者 赵飞 陈英华 +2 位作者 马征 李茜 明军 《储能科学与技术》 CAS CSCD 北大核心 2024年第7期2308-2316,共9页
钾离子电池因其能量密度高、廉价易得等特点,已成为有潜力的储能设备,尤其钾离子更小的斯托克斯半径,使超低温钾离子电池成为可能。然而,传统电解质会使钾离子电池在低温下生长枝晶,导致电池失效并造成安全隐患。因此,改善电解质的低温... 钾离子电池因其能量密度高、廉价易得等特点,已成为有潜力的储能设备,尤其钾离子更小的斯托克斯半径,使超低温钾离子电池成为可能。然而,传统电解质会使钾离子电池在低温下生长枝晶,导致电池失效并造成安全隐患。因此,改善电解质的低温特性对提高钾离子电池低温性能至关重要。本文综述了近些年钾离子电池低温电解质的研究进展,其大致可分为三类,即非水系电解液、水系电解液和固态电解质。其中,非水系电解液大多含弱溶剂化醚类溶剂和添加剂,提高界面去溶剂化过程的同时使电极表面形成良好的界面膜,以提高电池的低温性能;水系电解液通过引入特定的添加剂分子降低电解液凝固点的同时破坏H2O分子间氢键网络,实现电池低温性能;固态电解质以准固态电解质为主,使聚合物骨架孔道中保留少量液态电解液以提高电解质体相离子传输,并降低电解质与电极界面接触阻抗,最终提高电池的低温性能。 展开更多
关键词 钾离子电池 低温性能 非水系电解液 水系电解液 固态电解质
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植物DNA双链断裂修复机制及其在重离子诱变和基因编辑中的作用
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作者 隆静 陈婧敏 +3 位作者 刘霄 张一凡 周利斌 杜艳 《生物技术通报》 CAS CSCD 北大核心 2024年第7期55-67,共13页
在自然界中,植物会遭受各种环境或内源因素导致的DNA损伤,其中DNA双链断裂(double strand breaks,DSBs)的影响最为严重,如果修复不当,将导致基因组不稳定、基因突变甚至细胞死亡。一方面,植物进化出了强大且有序的损伤修复机制,以确保... 在自然界中,植物会遭受各种环境或内源因素导致的DNA损伤,其中DNA双链断裂(double strand breaks,DSBs)的影响最为严重,如果修复不当,将导致基因组不稳定、基因突变甚至细胞死亡。一方面,植物进化出了强大且有序的损伤修复机制,以确保其存活及正常繁衍;另一方面,基于修复过程的容错性及致突变性,T-DNA插入、基因编辑、物理诱变等技术广泛应用于动植物品种改良。相较于哺乳动物,植物DSBs修复通路及其分子机制报道较为有限。本文综述了植物对DSBs损伤的响应、主要修复途径及关键因子,介绍了通路机制尚未完全解析的替代末端连接(alternative end joining,Alt-EJ)的最新研究进展;此外,探讨了重离子束引起的植物DSBs修复特征和多途径选择,以及基于不同DSBs修复途径的基因编辑技术的研究进展,旨在为深入了解植物DSBs损伤响应及修复的分子机制和研发高效生物育种技术提供参考。 展开更多
关键词 植物DSBs损伤修复 同源重组 非同源末端连接 重离子束 基因编辑
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