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Radical-ionic metal-organic frameworks (MOFs) have unique optical, magnetic, and electronic properties. These radical ions, forcibly formed by external stimulus-induced redox processes, are structurally unstable and have short radical lifetimes. Here, we report two naphthalenediimide-based (NDI-based) Ca-MOFs: DGIST-6 and DGIST-7. Neutral DGIST-6, which is generated first during solvothermal synthesis, decomposes and is converted into radical-anionic DGIST-7. Cofacial (NDI) 2 •− and (NDI) 2 2− dimers are effectively stabilized in DGIST-7 by electron delocalization and spin-pairing as well as dimethylammonium counter cations in their pores. Single-crystal x-ray diffractometry was used to visualize redox-associated structural transformations, such as changes in centroid-to-centroid distance. Moreover, the unusual rapid reduction of oxidized DGIST-7 into the radical anion upon infrared irradiation results in effective and reproducible photothermal conversion. This study successfully illustrated the strategic use of in situ prepared cofacial ligand dimers in MOFs that facilitate the stabilization of radical ions.

This study reports on the dissolution behavior of SrO in LiCl at varying SrO concentrations from low concentrations to excess. The amount of SrO dissolved in the molten salt and the species present upon cooling were determined. The thermal behavior of LiCl containing various concentrations of SrO was investigated. The experimental results were compared with results from the simulated results using the HSC Chemistry software package. Although the reaction of SrO with LiCl in the standard state at 650 °C has a slightly positive Gibbs free energy, SrO was found to be highly soluble in LiCl. Experimentally determined SrO concentrations were found to be considerably higher than those present in used nuclear fuel (

An important property of glass and ceramic solid waste forms is processability. Tellurite materials with low melting temperatures and high halite solubilities have potential as solid waste forms. Crystalline TiTe3O8 was synthesized through a solid-state reaction between stoichiometric amounts of TiO2 and TeO2 powder. The resultant TiTe3O8 crystal had a three-dimensional (3D) structure consisting of TiO6 octahedra and asymmetric TeO4 seesaw moiety groups. The melting temperature of the TiTe3O8 powder was 820℃, and the constituent TeO2 began to evaporate selectively from TiTe3O8 above around 840℃. The leaching rate, as determined using the modified American Society of Testing and Materials static leach test method, of Ti in the TiTe3O8 crystal was less than the order of 10-4 g·m-2·d-1 at 90℃ for durations of 14 d over a pH range of 2-12. The chemical durability of the TiTe3O8 crystal, even under highly acidic and alkaline conditions, was comparable to that of other well-known Ti-based solid waste forms.

Environmental damage from serious nuclear accidents should be urgently restored, which needs the removal of radioactive species. Radioactive iodine isotopes are particularly problematic for human health because they are released in large amounts and retain radioactivity for a substantial time. Herein, we prepare platinum-coated iron nanoparticles (Fe@Pt) as a highly selective and reusable adsorbent for iodine species, i.e., iodide (I

We have developed a liquid level measurement system using the dynamic bubbler technique. Based on our previous methodology, herein, we established a field-applicable wireless measurement system to simultaneously monitor the liquid level and density of corrosive molten salts at high temperatures. The accuracy and precision of the present technique were suitable for applications in harsh field processes. Regardless of the base pressure under the present experimental conditions, percentage differences compared with reliable reference values in the literature were less than 10% in the temperature range 773–1123 K using KNO3 as a molten salt. Our dynamic bubbler technique produces an average percentage difference ca. 5–8% with a standard deviation of less than ca. 0.04 g cm−3 between measured and literature density values in all experiments, whereas the standard deviations in all liquid level measurements were less than 0.3 mm (0.07% relative standard deviation). The present technique is an excellent alternative to many conventional liquid level and density measurement techniques used under extreme environmental conditions characteristic of common industrial processes.

The intracellular delivery of functional proteins in their native forms into cells is a theme of paramount importance in research owing to their diverse biological applications. Porous inorganic nanoparticles are emerging as efficient nanocarriers for the delivery of small molecules and drugs. To expand the range of cargos from small molecules to large native functional proteins, cubic mesoporous silica nanoparticles (cMSNs) with a Pm3n pore symmetry with an average particle dimension of 180 nm were prepared. The as-prepared cMSNs were subsequently etched with a methanolic solution of Ca(NO3)2 to expand their mesopores and simultaneously remove the template. The original mesopores with a pore dimension of 2.41 nm partially collapsed and combined into ultra-large mesopores with an average pore diameter of 13.89 nm without perturbing the original cubic symmetry of the remaining mesopores. The maximum pore dimension was around 60 nm. Various techniques including powder X-ray diffraction, transmission electron microscopy, and electron tomography identified the unique three-dimensional structure of pore-enlarged cMSNs (Ca-cMSNs). Moreover, their surfaces were functionalized with a guanidinium-rich cell-penetrating R8-azido-peptide (p-azidophenylalanine-GSGSGGRRRRRRRR) through the click reaction. The intracellular delivery of functional proteins such as Cre recombinase into human TE671(LoxP-LacZ) cells was realized by using R8-Ca-cMSNs as native protein delivery synthetic nanocarriers. The delivery efficiency when using the R8-Ca-cMSNs significantly enhanced compared to that when using Ca-cMSNs without surface-bound cell-penetrating peptides.

We demonstrated that bromine in ethyl acetate can selectively separate metallic contents in lanthanide metal-oxide mixtures for analysis, which had been validated for uranium. This Br2-EtOAc dissolution method was applied to determine the constituents of metal and metal oxide in SIMFuel that was electrochemically reduced from oxide fuel in the molten salt. Compared with the analysis results obtained after dissolving the fuel in an acid solution, we concluded that the Br2-EtOAc method can be applied to uranium and rare earths but not to noble metals for the reduction yield determination.

Co-electrodeposition of uranium and molybdenum from a LiCl-KCl melt was investigated using cyclic voltammetry (CV), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The electrochemical study showed that the electrodeposition of Mo occurred from a molten LiCl-KCl eutectic at potentials more negative than −0.3 V vs. Ag|Ag+. Electrodeposition at a low overpotential range (between −0.3 V and −0.35 V) resulted in flat, thin Mo films, whereas greater overpotentials led to the growth of 3D films. Conditions for simultaneous electrodeposition of U and Mo were then optimized by varying the concentrations of UCl3 and MoCl3 and the electrodeposition method applied. At a constant potential of −1.58 V, a melt containing 1.3 wt% UCl3 and 1.5 wt% MoCl3 resulted in the co-electrodeposition of dendrites due to the high overpotential for Mo electrodeposition. However, diffusion-controlled electrodeposition using the same potential and concentration resulted in a uniform and flat U-Mo film. This co-electrodeposition of U-Mo films could be applied to the preparation of low-cost U-Mo nuclear fuel.

A long-lived radioisotope of iodine, 129I, is a fission product and is released into our environment by spent nuclear fuel reprocessing plants or nuclear accidents. The measurements pertaining to 129I are focused on evaluating the effects of using human-made nuclear fission products as environmental tracers and for monitoring samples from various types of matrices for regulating radioactive contaminants or radioactive waste repository safety. Thermal ionization mass spectrometry (TIMS), accelerator mass spectrometry (AMS), and inductively coupled plasma mass spectrometry (ICP-MS) have been applied to analyze 129I and the isotope ratio 129I/127I from the environment and food samples. The advantages of these techniques in determination of iodine are high sensitivity, reasonable analysis time, relatively simple sample preparation process, and applicability to a large number of samples. This review describes the technical strategies for quantifying 129I with the considerations of reducing the interference and matrix effect, decreasing the limit of detection, and availability of standard materials when using TIMS, AMS, and ICP-MS.

The influence of Gd-doping level and oxygen stoichiometry on the structural properties and electrochemical reactivity of U 1−y Gd y O 2±x have been investigated. The stoichiometry of UO 2 matrices with different Gd contents was determined using the lattice parameter obtained by XRD. The extent of lattice contraction, defined by a contraction factor, was found to be dependent on the stoichiometry. The surface morphologies exhibited differences in grain size which varied with stoichiometry and its influence on the U atom diffusivity during fabrication. The differences in grain size and, hence, the density of grain boundaries was reflected in variations in electrical conductivity, with hyperstoichiometric specimens with a low number of boundaries, yielding an increase in conductivity with increasing Gd content. Cyclic voltammetry showed that a variation in Gd content had only a minor influence on the electrochemical reactivity of stoichiometric U 1−y Gd y O 2 . By contrast, the reactivity of hypostoichiometric U 1−y Gd y O 2−x and hyperstoichiometric U 1−y Gd y O 2+x increased and decreased, respectively, with increasing Gd content. The formation of Gd-O v clusters in hyperstoichiometric U 1−y Gd y O 2+x has a more marked influence on reactivity than the accompanying changes in grain size and electrical conductivity.

An in-house manufactured liquid level measurement system based on dynamic tube pressure measurements was established for high-temperature corrosive molten salts. The accuracy and precision of the present technique depend on the furnace temperature, initial base tube pressure, and tube speed. Whereas the initial base tube pressure did not influence the performance of the measurements significantly, a set value of the critical pressure level for the detection of the liquid surface was an important factor, especially in case of the higher temperature experiments. Within a temperature range of 773–1073 K using KNO 3 , our technique could obtain a measurement error of less than ca. 0.05 mm in precision. The tube speed increased from 0.25 mm s −1 to 2.00 mm s −1 , resulting in a % departure of only 1.1%, 1.3%, and 1.9% at 773 K, 973 K, and 1073 K, respectively. The measurement of travel distance instead of measuring the liquid level is useful in terms of the calibration-free process monitoring. The gravimetric calibration method was also used to determine the total mass of the liquid, where the weight versus travel distance calibration curves showed an excellent linearity with R 2 = 0.9999 under all temperature conditions.

The development of van der Waals (vdW) parameters for molecular dynamics force fields typically requires fitting the parameters to reproduce experimental physical properties, such as the density or the heat of vaporization. These fitting procedures depend on a limited number of conformations, involve expensive DFT calculations, or need hand-tuning of the resulting parameters. Such methods have little to no support for the simultaneous fitting of the parameters, are time-consuming, and neglect coupling effects since each parameter is fitted individually rather than a common set of calculations where all parameters are derived simultaneously. Hence, in this study, we present a genetic algorithm (GA) that automates this fitting process. In this manner, the GA-based optimization can fit all the vdW terms at the same time and does not require any physical intervention. Once executed, the GA will automatically determine the optimum parameter set based on the properties included in the fitness function. The GA reported herein has been successfully applied to acetonitrile, a common organic solvent, to reasonably reproduce both the thermodynamic and dynamic properties at room temperature as well as in a wide temperature range. The use of GA not only serves as a powerful optimization tool but also opens up new avenues in the development of accurate force fields that can provide valuable molecular insights.

Magnetic core-shell ZnFe 2 O 4 /ZnS composites were synthesized through a two-step chemical process including the hydrothermal and the co-precipitation methods. The structural characterization revealed that the composites consisted of a layer of ZnS clusters on the surface of ZnFe 2 O 4 nanoparticles. The band gap energy of the composite was estimated to be 2.2 eV through the Kubelka–Munk plot, implying the possible application as a photocatalyst under the visible light radiation. The improved photocatalytic efficiency of the ZnFe 2 O 4 /ZnS composites was confirmed through the photocatalytic degradation of Methyl Orange. The increased absorption of the visible light and the enhanced separation of the electron-hole pairs due to the relative energy band positions in ZnFe 2 O 4 and ZnS are considered as the main advantages. Additionally, the moderate magnetization of the ZnFe 2 O 4 core insured the easy magnetic collection of the composite materials without affecting the photocatalytic performance. Our results showed that ZnFe 2 O 4 -based nanocomposites could be used as an effective and magnetic retrievable photocatalyst.

N-doped microporous carbon nanospheres (MCNs) are prepared directly from the as-prepared mesoporous silica nanospheres (MSNs) with a disordered pore structure by a new, simple and direct carbonization method. The as-prepared MSNs containing cetylpyridinium bromide (CTPB) template are effective for direct carbonization. Neither MSN with a two-dimensional hexagonal pore symmetry nor MSN with cetyltrimethylammonium bromide (CTAB) template is effective for this new method. Thus, this method is very cost-effective and environmentally benign. Furthermore, N-doping into the carbon matrix naturally occurrs during the carbonization process, because of the presence of pyridinium N atoms in the CTPB template. The N-doped MCN material is a good sorbent material for CO2 adsorption owing to the Lewis basic sites of N atoms as well as good microporosity. The low surface coverage isosteirc heat of CO2 adsorption (Qst) is calculated by the Clausius–Clapeyron equation using the data obtained at 273 and 298 K, and the calculated value of Qst is 58.4 kJ mol−1. This value is relatively very high compared to the other N-doped porous carbon materials. Both the Lewis basic sites of N atoms and uniform microporosity in the N-doped MCNs are responsible for this high value.

A dynamic tube pressure method was proposed for a liquid level measurement. The reliability of our in-house manufactured prototype level measurement system was investigated for water samples in a vial as a preliminary study. The prototype instrument, equipped with a stepper motor and a differential pressure sensor, was used to measure the travel distance of the tube from an initial zero position to the liquid surface. Unlike a conventional bubbler method, our dynamic tube pressure method is based on the abrupt changes in the tube pressure to directly detect the liquid surface. Optimum conditions were determined from the measurements of the travel distance with different-sized tubes at various ambient base pressures and various descending tube speeds. In addition, we proposed a gravimetric calibration method. In the gravimetric calibration method, the travel distances are used instead of the liquid level, which can be obtained from the measurement data of the travel distance. The travel distance versus the weight calibration curve showed a good linear relationship (R2 = 0.9999), and standard deviations of the travel distance over the whole range of experimental conditions were less than 0.1 mm. In a further study, our present system will also be used in the measurement of density and surface tension by minimizing the contact time with high-temperature and highly-corrosive molten salts.

UV–VIS spectra of uranium ions provided information not only on the electronic state of U(III)–Cl and U(IV)–Cl species, but also on the metal–ligand bonding properties. The 5f – 6d transition lines in the electronic absorption spectra of U(III) and U(IV) provided key information on the covalent bonding properties of U(III)–Cl and U(IV)–Cl complexes. The position and intensities of 5f – 6d and 5f – f5 transitions varied depending on the oxidation state and bonding properties. The 5f – 6d transitions of U(III) ion occur at a lower energy of as low as the 400–600 nm range with decreased intensity. However, U(IV) ions occur at the much higher ~ 250 nm range. The 5f – 6d / 5f – 5f intensity ratio indicated the degree of covalency. The U(III)–Cl species exhibited stronger covalent bonding than the U(IV)–Cl. This means that U(III)–Cl bonding is stronger than U(IV)–Cl species. Compared with uranium ions, Eu(II) ion showed no measurable covalent bonding under the same conditions, which means that Eu(II)–Cl bonding is predominantly ionic in nature. The bond strength (covalency) was evaluated in the order of U(III)–Cl > U(IV)–Cl ≫ Eu(II)–Cl. The reduction rate of U(IV) is ~ 4 times faster than that of the oxidation of U(III), indicating that U(III)–Cl is more stable than U(IV)–Cl species. The UV–VIS spectral analysis method may also be effective in investigating the bonding properties of neptunium and plutonium ions with chloride ligands in molten salt media.

We prepared neptunium chloride complexes electrochemically and performed spectroelectrochemical measurements of neptunium ions in LiCl–KCl eutectic melts at 450 °C, where the neptunium concentrations studied were in the range of 0.1–1 mM. We observed a highly absorbing f–d transition band of Np3+ at 383 nm, which was used to determine an formal potential of the Np4+|Np3+ redox couple (E°′ = 0.45 V vs. Ag|Ag+) with a solution of concentration as low as ~0.1 mM. This result agreed well with the value (E°′ = 0.42 V vs. Ag|Ag+) determined by cyclic voltammetry with a ~15 mM solution.

In pursuit of superior TiO2 photoanode materials for dye-sensitized solar cells (DSSCs), we prepared lotus-root shaped meso-/macroporous TiO2. The lotus-root shaped meso-/macroporous TiO2 was easily prepared by using a cetyltrimethylammonium hydroxide (CTAOH) template in aqueous solution. The crystallization of the as-prepared amorphous lotus-root shaped TiO2 was performed at 700 °C in air. Crystalline anatase phase with a very small portion of rutile phase was generated after the heat treatment at 700 °C and the BET surface area of crystalline lotus-root shaped meso-/macroporous TiO2 material (LR-700) was 30.0 m(2) g(-1). The wall of LR-700 displayed well-developed mesoporosity with a pore dimension of 28.3 nm. Periodically arranged microscale one-dimensional (1D) macropores were also observed in the particles. The photon-to-current conversion efficiencies (η) of LR-700 photoanodes in Gratzel type DSSCs were examined. The conversion efficiency of DSSC prepared by mixing nanoparticulate Evonik P25 and LR-700 (ratio=85:150 by mass) was 28% greater compared to the reference electrode using P25. Incident photon-to-current efficiencies (IPCE) of the DSSCs were dramatically improved by employing the photoanodes composed of a mixture of P25 and LR-700 but impedance analysis indicated that P25/LR-700 mixed cells have resistances similar to the standard P25 reference cell. Thus, photovoltaic performances could be improved mainly due to the increases of dye uptake and external quantum efficiency by using a mixed photoanode composed of LR-700 and nanocrystalline P25 particles.

A graphene oxide embedded sol–gel (GOSG) film was utilized as a substrate for surface-assisted laser desorption/ionization mass spectrometry (SALDI MS). GOSG SALDI MS efficiently generated low-background metabolite fingerprints, especially from crude samples such as a microalgae culture sample.

Cyclic voltammetry (CV) and chronoamperometry (CA) were employed to develop a real-time monitoring system for the pyrochemical process. These electrochemical techniques showed a good linearity of the current and the passed charges with the concentration of a solute even up to 9 wt.% in a LiCl–KCl melt, showing the potential for real application. To apply CA to the pyrochemical process, where the concentration of actinides and/or lanthanides is largely variable, the repeating chronoamperometry was designed and successfully tested at a wide range of Nd 3 + ion concentration of up to 9 wt.%.

We prepared a series of bimodal mesoporous silicas (BMSs) using a mixed template system. Cetyltrimethylammonium hydroxide (CTAOH) and varying concentrations nonionic auxiliary templates, including Brij76, Brij72, Brij52, and Brij30, were employed as templates. These mixed template syntheses led to BMS materials with two different length scales of mesopores. The small mesopore was thought to be generated by the CTA + template, while the secondary large pore was produced by the auxiliary template. Depending on the chemical structure of the auxiliary template, the dimensions of the secondary large pore had systematically changed.

We characterized the lattice parameter and phase transformation behaviors of six uranium-based metallic fuels in the temperature range 303–1173 K using in situ high-temperature X-ray diffraction (HT-XRD). In all of the fuels, α-U crystal structure almost vanished at 1023 K while UO2 crystal structure started forming at 843 K. Pawley refinement of HT-XRD data revealed anisotropic lattice thermal expansion with increases along the a- and c-axes upon annealing in all the metallic fuels. Furthermore, we confirmed that rare-earth elements (Nd, Ce, Pr, and La) contained in the U–10Zr metallic fuel hardly influenced the thermal behavior of the lattice parameters.

Analysis of Experimental Study Tendency on Oriental Herbal Medicines for Male Infertility- Focusing on Domestic Theses for a Degree -Sang-Eun Bae 1 , Hee-Jeong Kim 1 , Seung-Yeol Lee 1 , Heung-Su Kim 1 Chul-Soo Kim 2 , In-Hyuck Ha 3 , Jin-Ho Lee 31 Dept. of Oriental Obstetrics & Gynecology, Gang-Nam Jaseng Hospital of Oriental Medicine 2 Dept. of Oriental Obstetrics & Gynecology, An-San Jaseng Hospital of Oriental Medicine 3 Dept. of Rehabilitation Medicine of Korean Medicine, Gang-Nam Jaseng Korean Medicine HospitalObjectives: The tendency of experimental studies on the male infertility w as analyzed through focusing on domestic theses for a degree to in dicate the hereafter direction for its study in oriental herbal medicine.Methods: 35 domestic theses for a degree published after 2003 were analyzed. And theses were classified by year, study design, degree and subjects.Results: The followings are the results of this study.1. 35 theses were reviewed. 11 master dissertations and 24 doct orate dissertations 2. In the annual publishing tendency, the number of theses bega n to increase from 2003 and the theses have been published actively from 2005.3. Classified by study design, 19 in vitro & in vivo and 16 in vitro experimental studies were performed.4. In the medication and prescription, the studies with single medication were 32, and prescription were 3. In the studies with single medication, four studies on Ginseng Radix (人蔘) were the most.5. In theses related to single medication, BoYang-Yak was most prefered, followed BoYeum-Yak, BoKi-Yak, SabJung-ChukNyo-JiDae-Yak.6. Analysed 35 theses by subject, concentrational experiments were 23, periodical experiment were 3, concentration al & periodical experiment was 1. 7. In theses related to herb medication, the themes were Body & testicular weight, sperm parameters, testosterone level, CREM mRNA level & CREM pr otein, seminiferous tubule and antioxidant activity.8. Related to herb medication's antioxidant activity efficacy w ere 7 theses.Conclusions: If there are more diverse studies on medication, prescription, external treatment methods and experiment methods in the future , this will be very helpful for the clinical treatment of male infertility. Key Words: Male Infertility, Oriental Herbal Medicine, Experimental Study, Infertility

This study aimed to investigate the effects of temperature on the black garlic manufacturing process. The moisture content, pH, browning intensity, S-allyl cysteine (SAC) content and antioxidant activity, including DPPH radical scavenging activity and reducing power, were determined. The moisture content of garlic gradually decreased throughout the heating process. The rate of moisture removal was higher at high temperatures compared with low temperatures. The pH also decreased more significantly in garlic heated at high temperatures. The browning intensity increased with increasing temperature. The SAC contents of black garlic were significantly different according to heating temperature; the garlic samples heated at a low temperature had a higher SAC contents. Antioxidant activity, as determined by the DPPH radical scavenging activity and reducing power, increased when the garlic was exposed to higher temperatures.

Magnetic core-shell ZnFe

E-mail: kjy@kaeri.re.krReceived August 1, 2012, Accepted August 20, 2012Key Words : Pyrochemical process, High-temperature viscosity measurement, LiCl-KCl eutectic, Uranium,LanthanidesPyrochemical process dealing with high-temperature LiCl-KCl molten salts comprising trivalent ions of actinides andlanthanides have been extensively investigated since it hassome advantages over the conventional wet chemical pro-cesses with respect to the volume reduction of the nuclearwastes, the recycling of spent fuels, the nuclear non-proliferation resistance, etc.

We have measured the electronic absorption spectra of the U (III) and U (IV) ions in a LiCl–KCl eutectic melt at 450 °C to understand their spectrochemical behavior in the context of pyrochemical process of spent nuclear fuel. The UV–VIS spectra of the U (III) ion consist of two main peaks in the range of 400–600 nm which are attributable to the 5f 3 – 5f 2 6d 1 transitions. The 5f – 6 d transitions of U (III) ion occurred at lower energy as low as 400–600 nm range while that of Nd (III) and U (IV) ion occur at much higher energy over the normal UV range. For the U (III) ion, the intensities of 5f – 5f transitions are about one order of magnitude larger than the 4f – 4f transitions in lanthanides. And the 5f – 6 d transitions are about one order of magnitude smaller than in the 4f – 5 d transitions in the lanthanide ions. The electronic energy levels of the U (III), U (IV) and Nd (III) ions are estimated to understand their electronic transitions. The features of the electronic absorption spectra of U (III), Nd (III), U (IV) ions are reasonably explainable by their electronic structure. In-situ monitoring of the U (III) ↔ U (VI) redox reaction in a high temperature LiCl–KCl showed that the redox reaction is reversible.

A sensitive and reproducible analytical method to measure S-allyl cysteine (SAC) in black garlic was developed using the HPLC-FLD (fluorescence detection) with prior derivatization with AccQ-Fluor Reagent. The results were then compared with those from obtained using the HPLD-UVD (ultraviolet detection) that has been conventionally used for measuring SAC in raw garlic. The SAC content in raw garlic measured by the HPLC-FLD and the HPLD-UVD were 21.52 and 22.73 μg/g, respectively. And these results were satisfactory with %CV (coefficient of variation) less than 2%. However, the application of the HPLC-UVD for the determination of SAC in black garlic was limited due to the high %CV that arose from the unstable baseline. However, the HPLC-FLD could be applied to the measurement of SAC in black garlic with satisfactory %CV. The HPLC-FLD method was validated by determining the linearity, limit of detection, limit of quantification, accuracy and precision. This method showed excellent linearity with a coefficient of determination (R2) greater than 0.998. The limits of detection (LOD) and the limit of quantification (LOQ) were 6.28 and 19.02 μg/mL, respectively. The accuracy ranged from 98.51 to 102.08%, and the precision of the method was found to be less than 2%.

The two-dimensional Pt submonolayers on Au(111) were used as model catalyst system to study kinetics of hydrogen oxidation reaction (HOR). The morphology of different Pt submonolayers was characterized by ex situ scanning tunneling microscopy combined with statistical image analysis. The HOR kinetics data were analyzed using Levich–Koutecky formalism and presented as a function of the mean size of Pt clusters for each Pt submonolayer. The Pt submonolayers with smaller Pt clusters were found less active for HOR. This trend is well correlated with the continuum elasticity analysis of the average active strain in Pt clusters indicating that smaller clusters have less tensile strain. The density functional theory calculations were found in agreement with our results demonstrating that the size-dependent strain in Pt clusters has significant effect on the energy of the d-band center, i.e., the Pt clusters’ activity.

Time-dependent elementary polarizations of a lithium-ion battery are quantitatively investigated below room temperature in an attempt to determine the critical factors affecting low temperature power decline. From three-electrode impedance measurements and the theoretical analysis of the phenomenological equivalent circuit, the proportional contribution of the internal resistances to the total polarization is satisfactorily analyzed as a function of the pulse discharging time. The results prove that the interfacial charge-transfer resistances of the anode (graphite) and the cathode (lithium cobalt dioxide) make the highest contributions to the low temperature power decline. On this basis, a strategy for the material design to enhance the low temperature performance is suggested with two examples of surface modification and hybridization with an electrochemical capacitor.

The study of the kinetics of metal deposition via surface limited red-ox replacement of underpotentially deposited metal monolayers is presented. The model system was Pt submonolayer deposition on Au(1 1 1) via red-ox replacement of Pb and Cu UPD monolayers on Au(1 1 1). The kinetics of a single replacement reaction was studied using the formalism of the comprehensive analytical model developed to fit the open circuit potential transients from deposition experiments. The practical reaction kinetics parameters like reaction half life, reaction order and reaction rate constant are determined and discussed with their relevance to design and control of deposition experiments. The effects of transport limitation and the role of the anions/electrolyte on deposition kinetics are investigated and their significance to design of effective deposition process is discussed.

We have measured the electronic absorption spectra of the U(III) ion in LiCl–KCl eutectic melt at 450 °C to understand its chemical behavior in the context of pyrochemical process of spent nuclear fuel. The UV–VIS spectra of the U(III) ion consist of two main peaks in the range of 400–600 nm which are attributable to the 5f 3 –5f 2 6d 1 transitions. With the aid of UV–VIS spectroscopic tool, in-situ measurement of chemical reactions of the U(III) with oxide ion as well as neodymium oxide was successfully achieved. The U(III) ion forms insoluble uranium oxide phases by reacting with oxide ion and lanthanide oxides.

Cyclic voltammetry (CV), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were employed to investigate the electrodeposition of Eu and Al in an LiCl–KCl eutectic melt containing Eu2+ and Al3+ at 450 °C. In order to deposit a pure Eu and Al alloy, the stoichiometrically lower concentration of Al3+ than that of Eu2+ and Al wires as a counter electrode was introduced into the bath of LiCl–KCl melt for the electrodeposition. The electrodeposition takes place at a potential more negative than −1.95 V vs. Ag|Ag+ while the deposit is oxidized at more positive potential than −1.92 V. Two new reduction peaks and an anodic peak on a W working electrode were observed at −2.39 V, −2.42 V, and −2.1 V, vs. Ag|Ag+, respectively, suggesting that the potential window of the Al system in LiCl–KCl melt can be extended to −2.43 V vs. Ag|Ag+. The EDS analysis indicated that AlEu can be deposited at the potential more negative than −2.37 V.

Electrochemical behaviors of and were investigated in LiCl-KCl eutectic molten salt by using various electrochemical techniques. The electrodeposition and dissolution currents for uranium show the maximum at -1.51V and -1.35V, respectively while, for gadolinium,at -2.15V and -1.9V, respectively. In case of LiCl-KCl molten salt containing both of and , the peak potential of electrodeposition of gadolinium shifts to more positive potential than in the solution without . The potentials in chronopotentiometric data suddenly dropped to negative value as soon as the reduction currents were applied and became constant at the potential around which the and are electrodeposited. The results of normal pulse voltammetry (NPV) and square wave voltammetry show that those methods can be used to qualitatively analyze the elements in the melts. Especially, the differentiation of NPV result was found to be useful for the separation of the peaks of which potentials are close each other.

The interactions of nitrate with Cu(100) and Cu(111) in acidic solution are studied by cyclic voltammetry (CV) and in situ electrochemical scanning tunneling microscopy (EC-STM). CV results show that reduction of nitrate on Cu(111) commences at 0.0 V vs. Ag/AgCl while the corresponding potential is -0.3 V on Cu(100). EC-STM images show that the terrace of both Cu(111) and Cu(100) are atomically flat at potentials more negative than -0.7 V. The Cu(100) surface exhibits flat terraces throughout the entire cathodic potential range. Close to OCP, step edges start to corrode. In contrast to Cu(100), the first layer of Cu(111) is converted to an atomically rough and defected surface-associated with nascent surface oxidation at potentials positive of -0.7 V. This surface oxidation is correlated with nitrate reduction.