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1
Content available remote Cations on Ion Chromatography by Phosphate-Coated Zirconia Stationary Phase Column
Mori M., Masuno T., Kozaki D., Nakatani N., Tanaka K., Itabashi H.
Acta Chromatographica
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2015
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Vol. 27, no. 4
767--773
EN
Ion chromatography of inorganic cations using a phosphate-coated zirconia stationary phase (PZ) was first attempted. The retentions of cations to PZ increased by elevating the column temperature and the reproducibility of the separation could improve at the higher temperature. The PZ functioned as a cation-exchanger from changes in the retention factor of cations as a function of eluent pH. Furthermore, the Gibbs free energies of cations were estimated from enthalpy and entropy using the retention factors of cations as a function of the column temperature. The reaction was based on the endothermic reaction.
2
Content available remote The characteristics of OSL signal from quartz grains extracted from modern sediments in Japan
Tokuyasu K., Tanaka K., Tsukamoto S., Murray A.
Geochronometria
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2010
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Vol. 37
13-19
EN
Quartz grains from sediments in Japan are derived from complex mixtures of sources, including volcanic, plutonic, metamorphic and sedimentary rocks. We have measured the OSL signal of quartz grains from modern coastal sediments derived from different source rocks and compared these characteristics with the likely source. Each sample shows a different combination of various OSL components. It is concluded that the source rock affects the characteristics of the OSL components from quartz grains in Japanese sediments. By comparing the LM-OSL signals from volcanic sources with those from various source rocks, it can be deduced that quartz which has a higher fast component ratio is more suitable for dating. We also conclude that volcanic source areas should be avoided.
3
Content available remote Use of combined ion-exclusion and cation-exchange chromatography to study photooxidation of ionic nitrogen compounds on a titanium dioxide photocatalyst
Mori M., Taoda H., Itabashi H., Ikedo M., Tanaka K.
Acta Chromatographica
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2006
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No. 16
28-37
EN
Combined ion-exclusion and cation-exchange chromatography (IEC/CEC) on a weakly acidic cation-exchange resin in the H+-form (TSKgel Super IC-A/C) has been used as an advanced method for evaluation of the photooxidation of ionic nitrogen compounds, for example triethanolamine, trimethylamine, and urea, on a TiO2 photocatalyst. Formation of NH4+ and NO3- from each nitrogen compound by photooxidation on the catalyst du-ring UV irradiation was successfully monitored by use of IEC/CEC under optimized mobile-phase conditions (6 mM tartaric acid and 3 mM 18-crown-6). It was found that the products formed depended on whether or not a mole-cule contained a hydroxylated nitrogen moiety or other hydroxyl group.
4
Content available remote Modeling of ion-exclusion and vacancy ion-exclusion chromatography on a strongly acidic cation-exchange resin in the H+ form
Kaczmarski K., Mori M., Głód B., Kowalska T., Tanaka K.
Acta Chromatographica
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2005
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No. 15
66-81
EN
Ion-exclusion chromatography (IEC) can sometimes be used for se-paration of the weak acids using pure water as mobile phase. Characteristic leading (i.e. frontally tailing) peaks are obtained and retention depends on the concentration of solutes. It was recently shown that this order could be reversed. In vacant ion exclusion chromatography (vIEC) sample flows as mobile phase and pure water is injected as the sample. Symmetrical peaks are obtained; this is believed to be because of self-buffering of the solutes in the sample. The aim of the work discussed in this paper was to describe the mechanism of retention in IEC and vIEC by using the modified equi-librium–dispersive (ED) model. It was found that the retention times and peak shapes predicted by the derived equations are in good agreement with experimental data. These equations also predict new features of vIEC, and these were confirmed experimentally. It was shown that in vIEC, in con-trast with IEC, symmetrical peaks are obtained even for a single analyte.
5
Content available remote Ion chromatography of common anions by use of a reversed-phase column dynamically coated with fluorine-containing surfactant
Helaleh M. I. H., Al-Omair A., Tanaka K., Mori M.
Acta Chromatographica
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2005
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No. 15
247-257
EN
A method with unusual selectivity has been developed for determi-nation of common anions such as chloride, bromide, nitrite, sulfate, phosphate, and iodide. The method uses with reversed-phase columns (graphite carbon and ODS), coated with fluorine-containing surfactant, and conductivity detection. A graphitized carbon column was selected for this study because of its high chemical stability, reliability, and reproducibility. Separation of common anions was achieved in 12 min. Calibration plots of peak area against anion concentrations were linear in the range 1–15 µg mL-1 for Cl-, 1–20 µg mL-1 for Br- and SO42-, and 3–20 µg mL-1 for I- and NO3-, with good correlation coefficients (r2 = 0.9922). Detection limits calculated for a signal-to-noise ratio (S/N) of 3 ranged from 0.76 to 0.98 µg mL-1. The reproducibility of retention times was varied from 0.28 to 0.45 relative standard deviation (RSD,%) and reproducibility of chromatographic peak areas was 2.13–3.25 (RSD,%).The method was successfully applied to the determination of anions in acid rain and related natural waters, including rain, river, and underground water.
6
Content available remote Deformation behavior of TiNi shape-memory alloy under strain- or stress-controlled conditions
Tobushi H., Okumara K., Endo M., Tanaka K.
Archives of Mechanics
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2002
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Vol. 54, nr 1
75-91
EN
The deformation properties of TiNi shape-memory alloy subjected to strain control and stress control were investigated experimentally. The results obtained are summarized as follows. (1) In the case of a full loop, the stress-strain curves under stress-controlled conditions are similar to those under strain-controlled conditions with high strain rate. The overshoot and undershoot do not appear at the start points of the stress-induced martensitic transformation in these curves. (2) In the case of subloop under stress-controlled conditions, temperature decreases and therefore the strain increases owing to the martensitic transformation at the early stage of the unloading process. At the early stage in the reloading process, temperature increases and therefore the strain decreases owing to the reverse transformation. (3) In the case of subloop under stress-controlled conditions, the starting stresses of the martensitic transformation and the reverse transformation in the loading and unloading processes coincide with the transformation stresses under strain-controlled conditions with low strain rate, respectively. (4) The deformation behaviours for a subloop under stress-controlled conditions are prescribed by the condition for progress of the martensitic transformation based on the transformation kinetics. (5) The deformation behaviors subjected to cyclic loading under stress-controlled conditions at constant temperature are also prescribed by the conditions for progress of the martensitic transformation.
7
Content available remote The role of backstress in phase transforming steels
Fischer F., Antretter T., Azzouz F., Cailletaud G., Pineau A., Tanaka K., Nagayama K.
Archives of Mechanics
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2000
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Vol. 52, nr 4-5
569-588
EN
Transformation induced plasticity (TRIP) is demonstrated by an experimental programme for a Fe-9Ni-12Cr steel for various loading paths with partial or full unloading. The martensitic transformation is considered. A thermodynamical interpretation as well as micromechanical modelling of TRIP are presented. The selection of distinct variants is explained. Finally a modified constitutive equation for the TRIP strain rate is suggested by introducing a transformation surface including a transformation backstress. The backflow after unloading, which cannot be explained by the currently used TRIP strain rate term, can be represented by the proposed formulation. Aspects of future research are discussed.
8
Content available remote Sepharose-DTNB covalent affinity chromatography of hepatic metallothionein from Cu-treated rats
Kabziński A. K. M., Takagi T., Tanaka K.
Chemia Analityczna
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1999
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Vol. 44, No. 5
805-823
EN
Covalent affinity chromatography with thiol-disulphide interchange (CAC-- TDI) on Sepharose-DTNB gel was employed for separation of Cu-thionein (Cu-Th) from the łivers of Cu induced white rats (3.0 mg of Cu per kg body weight, administered subcutaneously in physiological saline). Cu-thionein was prepared by gel permeation chro-matography (GPC) on Sephadex G-200 geł. The metallothionein protein (MT) was fractionated by two-, three- and four-step elutions. The CU(2+) ion dissociated fi.om Cu-thionein and protein aggregated by thiol-thiol intermolecular oxidation and mercaptide bonds (oligoaggregates and polyaggregates) and intramolecular formation of disulphide and mercaptide bridges in the lightmass monomer resulted from the contact with cova-lent affinity chlomatography support, inferred from rechromatoglraphy on Sephadex G-200. The dissociated CU(2+) appeared as a light complex with DTNB in fractions about 2000-2800 Da mass.
PL
Metodę chromatografii powinowactwa kowalencyjnego z wymianą mostków disiarczkowych (CAC- TDI) na złożu Sepharose-DTND stosowano do rozdziału Cu-tioneiny (Cu- Th) z wątroby białych szczurów eksponowanych przy użyciu Cu (3.0 mg Cu na kg wagi ciała, w postaci CUSO4 podawanego podskórnie w roztworze soli fizjologicznej). Cu-tioneina była otrzymywana metodą klasycznej chromatografii żelowej (GPC) na żelu Sephadex G-200. Białko metalotioneinowe frakcjonowano przy użyciu dwu-, trój- i czterostopniowej elucji. Podczas rozdziału jony CU2+ dysocjowały z Cu-tioneiny i powstały agregaty białkowe w wyniku utleniania grup tiolowych oraz tworzenia się wiązań merkaptydowych (oligoagaty i poliagregaty). W wyniku kontaktu ze złożem do chromatografii powinowactwa kowalencyjnego powstawały także wewnątrzcząsteczkowe mostki disiarczkowe oraz merkaptydowe w monomerach o niskiej masie cząsteczkowej, co potwierdzano rechromatografując powstałe frakcje na żelu Sephadex G-200. Dysocjujące jony Cu(2+) występowały w niskocząsteczkowej frakcji, jako kompleksy z DTNB o masie w granicach 2000 --28OO Da.
9
Content available remote Transformation conditions in an Fe-based shape memory alloy: an experimental study
Tanaka K., Watanabe T.
Archives of Mechanics
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1999
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Vol. 51, nr 6
805-832
EN
Martensite and austenite start conditions are studied experimentally in an Fe-9% Cr-5%Ni-14%Mn-6%Si polycrystalline SMA under combined tension/compression-torsion loads. The martensite start condition is represented by an oval cone in the stress-temperature space, thus being different from the von Mises theory. The third invariant of the stress deviator has a marked effect. The austenite start condition is expressed by a polygonal cone in the same stress-temperature space. Each side of the cone corresponds to the martensite variants preferably induced during mechanical loading. The direction of the austenite start plane is determined by the direction of loading whereas the amount of variants governs the position of the plane.
10
Content available remote Shape memory alloy preparation for multiaxial tests and identification of fundamental alloy performance
Tanaka K., Kitamura K., Miyazaki S.
Archives of Mechanics
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1999
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Vol. 51, nr 6
785-803
EN
TiNi shape memory alloy preparation for the multiaxial tests was explained. Stable response of the alloy was realized, not by training but by an effective combination of the alloying technique and the heat treatment: Ti-51.0 at%Ni polycrystalline shape memory alloy heat-treated by annealing at 673 K for 3.6 ks followed by cooling in a furnace. Some preliminary tests were performed to identify the fundamental alloy characteristics: the transformation temperatures, the stress-strain curves at several temperatures and the strain-temperature curves under constant hold stresses.
11
Content available remote Fatigue properties of TiNi shape memory alloy and applications to a heat engine and an actuator
Tobushi H., Nakahara T., Hashimoto T., Shimeno Y., Tanaka K.
Archives of Mechanics
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1999
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Vol. 51, nr 6
833-845
EN
The fatigue properties of a TiNi shape-memory alloy (SMA) wire in the region of the martensitic transformation and the R-phase transformation are investigated. The rotating-bending fatigue life of a wire in the region of the R-phase transformation is longer than 10'7 cycles. A tilt-disk offset SMA heat engine and an indirect-heated SMA thermal actuator are developed.
12
Content available remote Experimental methodology for TiNi shape memory alloy testing under complex stress state
Raniecki B., Dietrich L., Kowalewski Z., Socha G., Miyazaki S., Tanaka K., Ziółkowski A.
Archives of Mechanics
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1999
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Vol. 51, nr 6
727-744
EN
The experimental method and preliminary results of multiaxial proportional loadings at a range of different temperatures are discussed for the TiNi shape memory alloy. The results are limited to the R-phase reorientation and transformation pseudoelasticity of the material tested at the selected constant temperatures. The main objective of the paper is to develop experimental knowledge of the shape memory alloy properties under complex stress states which would allow better understanding of the material behaviour and create a basis for theoretical modelling.
13
Content available remote Deformation behaviour of TiNi shape memory alloy undergoing R-phase reorientation in torsion-tension (compression) tests
Raniecki B., Miyazaki S., Tanaka K., Dietrich L., Lexcellent C.
Archives of Mechanics
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1999
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Vol. 51, nr 6
745-784
EN
The deformation behaviour associated with the R-phase reorientation is investigated in a Ti-51.0 at%Ni polycrystalline shape memory alloy under the torsion-tension (compression) stress state, and special theoretical framework is developed to describe the observed alloy performance. The limit condition to start the reorientation process, represented as a surface on the axial stress-shear stress plane, is determined for the proportional loading path. The result is well described, not by the Huber-Mises condition (the J2-theory) but by the model (the J3-theory), by taking into account the third invariant of stress deviator through the concept of the shape function. The values of the shape function are determined experimentally. The basic experimental features of the deformation in the R-phase, such as the flow rule, the ratios of the reorientation strain rates and the dimensionless ratio of the reorientation work, are compared with the predictions of theories that neglect the effects of pressure, compressibility of reorientation strains and effects of induced anisotropy. The J3-theory turns out to be more realistic than the J2-theory.
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