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The Roles of Key Electrolytes in Balancing Blood Acid-Base and Nutrient in Broiler Chickens Reared under Tropical Conditions 被引量:2
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作者 Ibukun Olukorede Popoola Oluwabukola Rashidat Popoola +2 位作者 Matthew Oluwatobi Ojeniyi Oluwaseyi Olamide Olajide Eustace Ayemere Iyayi 《Natural Science》 2020年第1期4-11,共8页
The loss of electrolyte balance in diets of broiler chickens has resulted in a serious distur-bance of blood acid-base balance, coupled with elevated body temperature. The body losses carbon dioxide (CO2) and bicarbon... The loss of electrolyte balance in diets of broiler chickens has resulted in a serious distur-bance of blood acid-base balance, coupled with elevated body temperature. The body losses carbon dioxide (CO2) and bicarbonate (HCO3), resulting in respiratory alkalosis or acidosis. Under tropical conditions of high environmental temperatures, the balance of electrolytes in feeds must be set much higher as to maintain equal metabolic and digestive efficiency. However, information on the ideal dietary electrolyte balance (DEB) that could effectively correct acid-base imbalance in broiler chickens under severe heat stress condition is scanty. Therefore, the effects of varying electrolyte balance in diets on haematology, blood glucose and serum inorganic elements were assessed in broiler chickens at starter (0 - 21 d) and finisher (22 - 35 d) phases, under temperature-humidity index of 24.97 - 35.19. One day-old Arbor Acre chicks (n = 300) were procured and randomly allotted to diets supplemented with potassium chloride and sodium bicarbonate, to balance monovalent ions (sodium, potassium and chloride) at 210 (T1), 240 (T2), 270 (T3), 300 (T4), 330 (T5) and 360 (T6) mEq/kg DEB, in a completely randomised design. On days 21 and 35, blood (5 mL) samples were collected from birds in each replicate whose weights were closest to the mean class weight for haematology and serum biochemical indices using standard procedures. Data were analysed using descriptive statistics and ANOVA at α = 0.05. Different levels of DEB did not significantly affect (P > 0.05) haematology and blood glucose at starter phase. However, at finisher phase, heterophil: lymphocyte of birds on 270 and 240 mEq/kg DEB were lower (P < 0.05) compared to other dietary treatments. Blood acid-base balance was relatively enhanced in birds on aggregate DEB level of 360 mEq/kg with reduced chloride ion and relatively lower incidence of hemodilution with respect to high haemoglobin levels as this level is advantageous in balancing blood acid to base ratio in broiler chickens reared under severe environmental temperatures higher than 43?C ± 5?C as against some previous opinions that did not take into consideration, the inherent dietary electrolyte balance in feedstuff, other functional mono or divalent ions, and the severity of environmental factors. 展开更多
关键词 BLOOD acid-base Monovalent ions BROILERS BLOOD GLUCOSE Heat Stress Serum MINERALS
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A critical assessment of the roles of water molecules and solvated ions in acid-base-catalyzed reactions at solid-water interfaces
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作者 Xugang Yang Zonghui Liu +2 位作者 Guoliang Wei Yu Gu Hui Shi 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期1964-1990,共27页
Solid-aqueous interfaces and phenomena occurring at those interfaces are ubiquitously found in a plethora of chemical systems.When it comes to heterogeneous catalysis,however,our understanding of chemical transformati... Solid-aqueous interfaces and phenomena occurring at those interfaces are ubiquitously found in a plethora of chemical systems.When it comes to heterogeneous catalysis,however,our understanding of chemical transformations at solid-aqueous interfaces is relatively limited and primitive.This review phenomenologically describes a selection of water-engendered effects on the catalytic behavior for several prototypical acid-base-catalyzed reactions over solid catalysts,and critically assesses the general and special roles of water molecules,structural moieties derived from water,and ionic species that are dissolved in it,with an aim to extract novel concepts and principles that underpin heterogeneous acid-base catalysis in the aqueous phase.For alcohol dehydration catalyzed by solid Bronsted acids,rate inhibition by water is most typically related to the decrease in the acid strength and/or the preferential solvation of adsorbed species over the transition state as water molecules progressively solvate the acid site and form extended networks wherein protons are mobilized.Water also inhibits dehydration kinetics over most Lewis acid-base catalysts by competitive adsorption,but a few scattered reports reveal substantial rate enhancements due to the conversion of Lewis acid sites to Brønsted acid sites with higher catalytic activities upon the introduction of water.For aldol condensation on catalysts exposing Lewis acid-base pairs,the addition of water is generally observed to enhance the rate when C–C coupling is rate-limiting,but may result in rate inhibition by site-blocking when the initial unimolecular deprotonation is rate-limiting.Water can also promote aldol condensation on Brønsted acidic catalysts by facilitating inter-site communication between acid sites through hydrogen-bonding interactions.For metallozeolite-catalyzed sugar isomerization in aqueous media,the nucleation and networking of intrapore waters regulated by hydrophilic entities causes characteristic enthalpy-entropy tradeoffs as these water moieties interact with kinetically relevant hydride transfer transition states.The discussed examples collectively highlight the utmost importance of hydrogen-bonding interactions and ionization of covalently bonded surface moieties as the main factors underlying the uniqueness of water-mediated interfacial acid-base chemistries and the associated solvation effects in the aqueous phase or in the presence of water.A perspective is also provided for future research in this vibrant field. 展开更多
关键词 acid-base catalysis Solid-aqueous interfaces Water Aqueous-phase reaction Hydronium ion Hydrogen-bonding interaction Local ionic strength effect
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Contacted Ion Pairs in Aqueous CuCl2 by the Combination of Ratio Spectra, Difference Spectra, Second Order Difference Spectra in the UV-Visible Spectra
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作者 鞠思文 张宁 +4 位作者 王志强 张睿挺 曾德文 邵晓鹏 林珂 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第6期657-663,I0001,I0002,共9页
The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the... The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the UV-visible spectra of thin fihn of CuCl2/H2O solutions at different concentrations. This method is the combination of ratio spectra, difference spectra and second order difference spectra. By using this method, two new bands at -230 and -380 nm are obviously observed. The bands are assigned as the contacted ion pairs [CuCl3(H2O)n]- or [CuCl4(H2O)n]2-, which demonstrates that ion pairs exist in the CuCl2/H2O solution. Such finding agrees with the recent theoretical spectra obtained by time-dependent density functional theory. Furthermore, the populations of the contacted ion pairs are discussed. This study not only offers the direct spectroscopic evidence of [CuCl3(H2O)n]- or [CuCl4(H2O)n]2- in aqueous CuCl2, but also suggests that the spec- troscopic analysis method is powerful to extract the weak bands in a strong overlapping spectrum. 展开更多
关键词 UV-visible spectroscopy Ratio spectra Difference spectra CuCl2/H2O solution ion pair
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Ion Pairing Kinetics Does not Necessarily Follow the Eigen-Tamm Mechanism 被引量:2
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作者 Qiang Zhang Bing-bing Zhang +1 位作者 Ling Jiang Wei Zhuang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期694-700,I0004,共8页
The most recognized and employed model of the solvation equilibration in the ionic solutions was proposed by Eigen and Tamm, in which there are four major states for an ion pair in the solution: the completely solvat... The most recognized and employed model of the solvation equilibration in the ionic solutions was proposed by Eigen and Tamm, in which there are four major states for an ion pair in the solution: the completely solvated state, 2SIP (double solvent separate ion pair), SIP (single solvent separate ion pair), and CIP (contact ion pair). Eigen and Tamm suggested that the transition from SIP to CIP is always the slowest step during the whole pairing process, due to a high free energy barrier between these two states. We carried out a series of potential of mean force calculations to study the pairing free energy profiles of two sets of model mono- atomic 1:1 ion pairs 2.0:x and x:2.0. For 2.0:x pairs the free energy barrier between the SIP and CIP states is largely reduced due to the salvation shell water structure. For these pairs the SIP to CIP transition is thus not the slowest step in the ion pair formation course. This is a deviation from the Eigen-Tamm model. 展开更多
关键词 ion pairing Eigen-Tamm model Potential of mean force
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Has Stewart approach improved our ability to diagnose acid-base disorders in critically ill patients? 被引量:2
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作者 Fabio D Masevicius Arnaldo Dubin 《World Journal of Critical Care Medicine》 2015年第1期62-70,共9页
The Stewart approach-the application of basic physicalchemical principles of aqueous solutions to blood-is an appealing method for analyzing acid-base disorders. These principles mainly dictate that p H is determined ... The Stewart approach-the application of basic physicalchemical principles of aqueous solutions to blood-is an appealing method for analyzing acid-base disorders. These principles mainly dictate that p H is determined by three independent variables, which change primarily and independently of one other. In blood plasma in vivo these variables are:(1) the PCO2;(2) the strong ion difference(SID)-the difference between the sums of all the strong(i.e., fully dissociated, chemically nonreacting) cations and all the strong anions; and(3) the nonvolatile weak acids(Atot). Accordingly, the p H and the bicarbonate levels(dependent variables) are only altered when one or more of the independent variables change. Moreover, the source of H+ is the dissociation of water to maintain electroneutrality when the independent variables are modified. The basic principles of the Stewart approach in blood, however, have been challenged in different ways. First, the presumed independent variables are actually interdependent as occurs in situations such as:(1) the Hamburger effect(a chloride shift when CO2 is added to venous blood from the tissues);(2) the loss of Donnan equilibrium(a chloride shift from the interstitium to the intravascular compartment to balance the decrease of Atot secondary to capillary leak; and(3) the compensatory response to a primary disturbance in either independent variable. Second, the concept of water dissociation in response to changes in SID is controversial and lacks experimental evidence. In addition, the Stewart approach is not better than the conventional method for understanding acid-base disorders such as hyperchloremic metabolic acidosis secondary to a chloride-rich-fluid load. Finally, several attempts were performed to demonstrate the clinical superiority of the Stewart approach. These studies, however, have severe methodological drawbacks. In contrast, the largest study on this issue indicated the interchangeability of the Stewart and conventional methods. Although the introduction of the Stewart approach was a new insight into acid-base physiology, the method has not significantly improved our ability to understand, diagnose, and treat acid-base alterations in critically ill patients. 展开更多
关键词 acid-base metabolism STEWART approach Base excess BICARBONATE Anion GAP STRONG ion difference STRONG ion GAP
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Sympathetic Cooling of ^(40)Ca^(+_27)Al^+ Ion Pair Crystal in a Linear Paul Trap 被引量:1
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作者 商俊娟 崔凯枫 +4 位作者 曹健 汪绍茂 晁思嘉 舒华林 黄学人 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期49-52,共4页
The 27Al+ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it canno... The 27Al+ ion optical clock is one of the most attractive optical clocks due to its own advantages such as low black-body radiation shift at room temperature and insensitivity to the magnetic drift. However, it cannot be laser-cooled directly in the absence of 167nm laser to date. This problem can be solved by sympathetic cooling. In this work, a linear Paul trap is used to trap both 40Ca+ and 27A1+ ions simultaneously, and a single Dopplercooled 40Ca+ ion is employed to sympathetically cool a single 27A1+ ion. Thus a 'bright-dark' two-ion crystal has been successfully synthesized. The temperature of the crystal has been estimated to be about 7mK by measuring the ratio of carrier and sideband spectral intensities. Finally, the dark ion is proved to be an 27Al+ ion by precise measuring of the ion crystal's secular motion frequency, which means that it is a great step for our 2Z Al+ quantum logic clock. 展开更多
关键词 Sympathetic Cooling of ion pair Crystal in a Linear Paul Trap is CA been in AL
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Ion-pairing HPLC methods to determine EDTA and DTPA in small molecule and biological pharmaceutical formulations 被引量:4
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作者 George Wang Frank P. Tomasella 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第3期150-156,共7页
Ion-pairing high-performance liquid chromatography-ultraviolet (HPLC-UV) methods were developed to determine two commonly used chelating agents, ethylenediaminetetraacetic acid (EDTA) in Abilify (a small molecule... Ion-pairing high-performance liquid chromatography-ultraviolet (HPLC-UV) methods were developed to determine two commonly used chelating agents, ethylenediaminetetraacetic acid (EDTA) in Abilify (a small molecule drug with aripiprazole as the active pharmaceutical ingredient) oral solution and die- thylenetriaminepentaacetic acid (DTPA) in Yervoy (a monoclonal antibody drug with ipilimumab as the active pharmaceutical ingredient) intravenous formulation. Since the analytes, EDTA and DTPA, do not contain chromophores, transition metal ions (Cu2+, Fe3+) which generate highly stable metallocom- plexes with the chelating agents were added into the sample preparation to enhance UV detection. The use of metallocomplexes with ion-pairing chromatography provides the ability to achieve the desired sensitivity and selectivity in the development of the method. Specifically, the sample preparation in- volving metallocomplex formation allowed sensitive UV detection. Copper was utilized for the de- termination of EDTA and iron was utilized for the determination of DTPA. In the case of EDTA, a gradient mobile phase separated the components of the formulation from the analyte. In the method for DTPA, the active drug substance, ipilimumab, was eluted in the void. In addition, the optimization of the concentration of the ion-pairing reagent was discussed as a means of enhancing the retention of the aminopolycarboxylic acids (APCAs) including EDTA and DTPA and the specificity of the method. The analytical method development was designed based on the chromatographic properties of the analytes, the nature of the sample matrix and the intended purpose of the method. Validation data were presented for the two methods. Finally, both methods were successfully utilized in determining the fate of the chelates. 展开更多
关键词 EDTA DTPA ion-pairing HPLC ARIPIPRAZOLE IPILIMUMAB
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An intravenous clarithromycin lipid emulsion with a high drug loading, H-bonding and a hydrogen-bonded ion pair complex exhibiting excellent antibacterial activity 被引量:1
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作者 Haoyu Gong Sicong Geng +7 位作者 Qi Zheng Puxiu Wang Lifeng Luo Xiuzhi Wang Yan Zhang Yu Zhang Haibing He Xing Tang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第5期618-630,共13页
The aim of this study was to develop an intravenous clarithromycin lipid emulsion(CLE)with good stability and excellent antibacterial activity. The CLE was prepared by the thinfilm dispersed homogenization method. The... The aim of this study was to develop an intravenous clarithromycin lipid emulsion(CLE)with good stability and excellent antibacterial activity. The CLE was prepared by the thinfilm dispersed homogenization method. The interaction between clarithromycin(CLA) and cholesteryl hemisuccinate(CHEMS) was confirmed by DSC, FT-IR and^1H NMR analysis. The interfacial drug loading, thermal sterilization, freeze–thaw stability, and in vitro and in vivo antibacterial activity were investigated systematically. DSC, FT-IR and^1H NMR spectra showed that CHEMS(CLA: CHEMS, M ratio 1:2) could interact with CLA through H-bonding and a hydrogen-bonded ion pair. The CHEMS was found necessary to maintain the stability of CLE.Ultracentrifugation showed that almost 88% CLA could be loaded into the interfacial layer.The optimized CLE formulation could withstand autoclaving at 121 °C for 10 min and remain stable after three freeze–thaw cycles. The in vitro susceptibility test revealed that the CLA–CHEMS ion-pair and CLE have similar activity to the parent drug against many different bacterial strains. The in vivo antibacterial activity showed that the ED50 of intravenous CLE was markedly lower than that of CLA solution administrated orally. CLE exhibited pronounced antibacterial activity and might be a candidate for a new nanocarrier for CLA with potential advantages over the current commercial formulation. 展开更多
关键词 CLARITHROMYCIN Cholesteryl hemisuccinate H-BONDING and HYDROGEN-BONDED ion pair COMPLEX Antibacterial activity Thin-film dispersed HOMOGENIZATion
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The Standard Association Constant of Ion Pair [GaCl]^(2+)in the System of HCl+GaCl_3+H_2O
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作者 Jia Zhen YANG Ru Bo ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第5期442-443,共2页
The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated... The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated and it was pointed that the association entropy is driving force to form the ionic pair. 展开更多
关键词 ion pair association entropy EMF GaCl3.
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Thermodynamics of Ion Pair of Magnesium Sulfate in Mixed Solvent
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作者 YANG Jia-zhen CHANG Xiao-hong LU Xing-mei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第3期403-405,共3页
Introduction Magnesium sulfate is an archetypal 2-2 salt that plays a central role in defining the characteristics of higher valent electrolyte solutions and its solution has been widely used to test various theories... Introduction Magnesium sulfate is an archetypal 2-2 salt that plays a central role in defining the characteristics of higher valent electrolyte solutions and its solution has been widely used to test various theories of strong electrolyte behavior and to develop models of ion association in solution. Up to now, the ion pairs of magnesium sulfate in an aqueous solution have been widely investigated by using different experimental techniques, such as conductometry , cryoscopy potentiometry solubility and Raman spectrometry. However, to our knowledge, no measurement of the standard association constant of the ion pairs, [ MgSO4 ]^0 in a glucosewater mixed solvent is available. 展开更多
关键词 Association constant Mixed solvent MgSO4 ion pair
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Ab Initio and DFT Study of Magnesium Sulfate Contact Ion Pairs
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作者 张星辰 张韫宏 李前树 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期190-193,共4页
The stuctures of contact ion pairs of magnesium sulfate were studied. The geometries of contact ion pairs of MgSO 4(H 2O) n (n =1-6) were optimized by using Hartree Fock (HF/6 31+G *, HF/6 311+G ** ) and... The stuctures of contact ion pairs of magnesium sulfate were studied. The geometries of contact ion pairs of MgSO 4(H 2O) n (n =1-6) were optimized by using Hartree Fock (HF/6 31+G *, HF/6 311+G ** ) and density functional theory (DFT) (B3LYP/6 31+G *, B3LYP/6 311+G ** ) methods. The stable structures of monodentate, bidentate and tridentate contact ion pairs were obtained. The bidentate structure of contact ion pairs are the most stable compaired with the monodentate and tridentate ones for the same composition. The hydration enthalpies of contact ion pairs of MgSO 4 (H 2O) n (n =1-4) increase with their hydration numbers. 展开更多
关键词 contact ion pair magnesium sulfate aqueous solution ab initio density functional theory
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Novel Properties of Supramolecular Complexes Formed by Pairing Cationic Porphyrin and Anionic Metal-Oxo Cluster
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作者 Shu Qing LIU Ji Qing XU Hao Ran SUN Department of Chemistry, Jilin University, Changchun 130023 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第9期831-834,共4页
MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the ... MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the relatively stable aggregates contain equal numbers of MTBPyP4(+) and SiW12O404-. 展开更多
关键词 cationic porphyrin anionic metal-ore cluster ion pair supramolecular complex
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9-ANTHROIC ACID SENSITIZED PHOTOLYSIS OF DIPHENYLIODONIUM SALTS THROUGH INTRA-ION PAIR ELECTRON TRANSFER
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作者 Xiu Zhi WANG Er Jian WANG (Institute of Photographic Chemistry. Academia Sinica, Beijing. 100101 National Laboratory of Applied orpeic Chemistry.Lanzhou University, Lanzhou. 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第10期831-834,共4页
We have studied 9-anthroic acid sensitized photolysis of dipbenyliodonius salts through fluorescence quenching, products analysis and Photo-CIDNP. The photoinduced electron transfer rate constant bas calculated to be ... We have studied 9-anthroic acid sensitized photolysis of dipbenyliodonius salts through fluorescence quenching, products analysis and Photo-CIDNP. The photoinduced electron transfer rate constant bas calculated to be 8.6×10 10/mol s. From photo-CIDNP study, both diphenyliodo and pbenyl radicals were confirmed as intermediates. Benzene is a cage escaped product from a singlet radical pair and diphenyliodonium Salt is a recombination preduct from a triplet radical pair. 展开更多
关键词 ion INTRA pair SENSITIZED ACID ANTHROIC
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EPR STUDY OF THE FORMATION OF[Li^+O^-]ION PAIR ON Li-DOPED ZnO
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作者 Ting Lu YANG Liang Bo FENG Shi Kong SHEN Han Qin Wang State key Laboratory of Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期251-254,共4页
In this letter the study of Li-doped zinc oxide by electron paramagnetic resonance method is described.A signal observed at g_=2.013,g_=1.955 on the degassed sample at 923K was designated to F_s^+ centers(surface oxyg... In this letter the study of Li-doped zinc oxide by electron paramagnetic resonance method is described.A signal observed at g_=2.013,g_=1.955 on the degassed sample at 923K was designated to F_s^+ centers(surface oxygen ion vacancies with a single trapped electron).When the sample was quenched from 1003K into liquid oxygen at 77K under 24 KPa O_2,[Li^+O^-] ion pairs valued at g_=2.026 and g=2.003 with superhyperfine constant a=2.0G,which resulted from ~7Li nucleus,formed at Li^+-substitutional site in ZnO lattice.A probable mechanism of [Li^+O^-]ion pair formation was proposed. 展开更多
关键词 LI EPR STUDY OF THE FORMATion OF[Li ion pair ON Li-DOPED ZnO ZNO
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INTRA-ION PAIR ELECTRON TRANSFER OF PHOTOEXCITED METHYLENE BLUE BORATE
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作者 Xiu Zhi WANG Han Qing CHEN Er Jian WANG (Institute of Photographic Chemistry, Academia Sinica, Beijing 100101National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou,730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第7期597-600,共4页
The photochemical reaction of methylene blue (n-butyltriphenyl) borate, MBRBPh3 was examined. The ultrafast quenching rate and large negative value of Delta G indicated that the intra-ion pair ET plays an important ro... The photochemical reaction of methylene blue (n-butyltriphenyl) borate, MBRBPh3 was examined. The ultrafast quenching rate and large negative value of Delta G indicated that the intra-ion pair ET plays an important role in photoreaction of MBRBPh3. The sequent boron- carbon bond cleavage of butyltriphenylboranyl radical intermediate was found by GC-MS and photo-CIDNP studies. 展开更多
关键词 ion INTRA-ion pair ELECTRON TRANSFER OF PHOTOEXCITED METHYLENE BLUE BORATE
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Synthesis and Crystal Structure of a Novel Ion-pair Compound Consisting of 1-(4-Bromobenzyl)pyridinium Cation and 7,7,8,8-Tetracyanoquinodimethanide Anion
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作者 周红波 陈友存 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第6期697-700,共4页
The title compound [BrBzPy][TCNQ] (BrBzPy^+=1-(4-bromobenzyl)pyridinium cation, TCNQ = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [BrBzPy]Br and LiTCNQ in ethanol solution and it... The title compound [BrBzPy][TCNQ] (BrBzPy^+=1-(4-bromobenzyl)pyridinium cation, TCNQ = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [BrBzPy]Br and LiTCNQ in ethanol solution and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.067(3), b = 7.3089(14), c = 23.796(4)A, β = 122.011(9)°, V= 2074.6(7)A^3, Z = 4, C24H15BrN5, Mr = 453.32, Dc = 1.451 g/cm^3,μ = 2.002 mm^-1, S = 1.047, F(000) = 916, R = 0.0398 and wR = 0.0921. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [BrBzPy]^+ cations. In a TCNQ column, the centroid-to-centroid distances of the neighboring anions of TCNQ are 3.2693 and 4.9464 A, respectively. 展开更多
关键词 TCNQ crystal structure ion-pair compound
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Synthesis and Crystal Structure of a Novel Ion-pair Compound Consisting of 1,3-Bis(4-cynobenzyl) Imidazole Cation and 7,7,8,8-Tetracyanoquinodimethanide Anion
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作者 陈友存 王芳芳 +1 位作者 王彦 汪快兵 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期900-904,共5页
A novel compound [(CNBz)2Im]2(TCNQ)3(CH3CN)((CNBz)2Im = 1,3-bis(4-cyano-benzyl) imidazole cation,TCNQ-1 = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [(CNBz)2Im]Br and Li... A novel compound [(CNBz)2Im]2(TCNQ)3(CH3CN)((CNBz)2Im = 1,3-bis(4-cyano-benzyl) imidazole cation,TCNQ-1 = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [(CNBz)2Im]Br and LiTCNQ in water and its structure was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/c with a = 10.1823(17),b = 20.292(3),c = 16.952(3) ,β = 104.73(0)°,V = 3387.6(10)3,Z = 4,C39H24N11,Mr = 646.69,Dc = 1.268 g/cm3,μ = 0.080 mm-1 and F(000) = 1340.The structure was solved by direct methods and refined to R = 0.0596 and wR = 0.0911 for 2690 observed reflections(Ⅰ 〉 2σ(Ⅰ)).The most prominent structural feature is that there are two types of TCNQ entries(TCNQ-1 and TCNQ0) in agreement with the IR spectra analysis of the compound. 展开更多
关键词 TCNQ crystal structure ion-pair compound
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Synthesis and Crystal Structure of an Ion-pair Compound: [H_2(teta)]^(2+)·[Ni(CN)_4]^(2-)·2H_2O (teta = Meso-5,7,7,12,14,14-hexamethyl- 1,4,8,11-tetraazacyclotetradecane)
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作者 丁建刚 耿飞 +1 位作者 李宝龙 张勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第1期25-28,共4页
The ion-pair compound [H2(teta)]^2+·[Ni(CN)4]^2-·2H2O (C20H42N8NiO2, teta = meso- 5,7,7,12,14,14-hexamethyl- 1,4,8,11-tetraazacyclotetradecane) was synthesized and characterized by single-crystal X-ra... The ion-pair compound [H2(teta)]^2+·[Ni(CN)4]^2-·2H2O (C20H42N8NiO2, teta = meso- 5,7,7,12,14,14-hexamethyl- 1,4,8,11-tetraazacyclotetradecane) was synthesized and characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P211n with a = 10.0784(10), b = 9.5411(7), c = 14.1010(14)А, β= 106.752(2)°, V= 1298.4(2)A^3, Mr = 485.33, Z= 2, De= 1.241 g/cm^3,μ(MoKα) = 0.778 mm^-1 and F(000) = 524. The structure was refined to R = 0.0391 and wR = 0.0870 for 2614 observed reflections with I 〉 2σ(I). The title compound contains one [Ni(CN)4]^2- anion, one protonated macrocyclic tetraamine cation [H2(teta)]^2+ and two water molecules. There are multiform hydrogen bonds in the compound to link the different components and stabilize the crystal structure. 展开更多
关键词 crystal structure tetraazacyclotetradecane hydrogen bond ion-pair compound
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The Kadomtsev-Petviashvili equation for dust ion-acoustic solitons in pair-ion plasmas
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作者 Hafeez Ur-Rehman 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期366-371,共6页
Using the reductive perturbation method,we have derived the Kadomtsev-Petviashvili(KP) equation to study the nonlinear properties of electrostatic collisionless dust ion-acoustic solitons in pair-ion(p-i) plasmas.... Using the reductive perturbation method,we have derived the Kadomtsev-Petviashvili(KP) equation to study the nonlinear properties of electrostatic collisionless dust ion-acoustic solitons in pair-ion(p-i) plasmas.We have chosen the fluid model for the positive ions,the negative ions,and a fraction of static charged(both positively and negatively) dust particles.Numerical solutions of these dust ion-acoustic solitons are plotted and their characteristics are discussed.It is found that only the amplitudes of the electrostatic dust ion-acoustic solitons vary when the dust is introduced in the pair-ion plasma.It is also noticed that the amplitude and the width of these solitons both vary when the thermal energy of the positive or negative ions is varied.It is shown that potential hump structures are formed when the temperature of the negative ions is higher than that of the positive ions,and potential dip structures are observed when the temperature of the positive ions supersedes that of the negative ions.As the pair-ion plasma mimics the electron-positron plasma,thus our results might be helpful in understanding the nonlinear dust ion acoustic solitary waves in super dense astronomical bodies. 展开更多
关键词 charged and static dust particles pair-ion plasma SOLITON
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Novel additives for the separation of organic acids by ion-pair chromatography
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作者 Zhong, Ying Ying Zhou, Wen Fang +2 位作者 Hu, Zhen Zhen Chen, Mei Lan Zhu, Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期453-456,共4页
This paper proposes the use of novel surfactant additives for the separation of organic acids by ion-pair chromatography and studies the influences of surfactants on the chromatographic separation behaviors.Researches... This paper proposes the use of novel surfactant additives for the separation of organic acids by ion-pair chromatography and studies the influences of surfactants on the chromatographic separation behaviors.Researches have been carried out on both silica gel matrix and polymer supporters in order to compare the two ordinary kinds of stationary phases,and the phenomenon is similar. Separation is based on differences in the stabilities of analyte-additive complexes in solution.Retention times of analytes can ... 展开更多
关键词 Organic acids ion-pair chromatography SURFACTANT Mobile phase additives
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