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X-ray fluorescence spectrometry using the "standardless" fundamental parameter method has been studied for the whole elemental analysis of magnesium alloys. Twelve major elements were determined: Mg, Al, Si, Ca, Mn, Fe, Ni, Cu, Zn, Ag, Sn and Pb. The specimens used were over 30 mm in diameter and greater than 10 mm thick to determine Sn Kα which has the largest analyzing depth (9 mm) through the alloy samples. The surfaces of the specimens were polished with fine alumina abrasive paper (#240) to remove the oxide layer and to avoid the influence of any surface roughness variation on the intensities of Mg Kα, Al Kα and Si Kα which have smaller analyzing depths. The total quantitative values of the 12 elements, determined by the FP calculation, were normalized to 100 mass%. The analytical values obtained by this method were comparable to those obtained by the conventional calibration curves method. The relative standard deviations were 6.6% for 0.0014 mass% of Ni, and 0.005% for 93.82 mass% of Mg in AZ91 series Mg alloys. The validation results of the proposed method for 12 elements were successful for the five CRMs tested.

Three kinds of bis(aromatic fluoride) compounds, 3,5-bis(4-fluorobenzoyl)biphenyl (1), 3,5-bis(4-fluorobenzoyl)-1,1′:4′,1″-terphenyl (2), and 3,5-bis(4-fluorobenzoyl)-1,1′:4′,1″:4″,1′′′-quaterphenyl (3), were synthesized by cross-coupling of the corresponding triflates with phenylboronic acid. Linear poly(ether ketone)s (1x, 2x, and 3x) having phenyl, biphenyl, and terphenyl side groups, respectively, were prepared by the polycondensation of the bis(aromatic fluoride) compounds with bisphenol A (a) and 4,4′-dihydroxybiphenyl (b) in N-methyl-2-pyrrolidone. The obtained poly(ether ketone)s were characterized by X-ray diffraction, differential scanning calorimetry, and thermogravimetry. The structure–property relationships of these poly(ether ketone)s were examined and compared with those of poly(ether ketone)s (4x) having no side group, which were prepared from 3,5-bis(4-fluorobenzoyl)benzene (4). The properties of the poly(ether ketone)s, solubilities, and thermal properties were compared and discussed based on the length of the side groups.

Aromatic polyimides (PI1x) with a tetraphenylnaphthalene unit between ether linkages were synthesized from 1,4-bis[4-(aminophenoxy)phenyl]-2,3-diphenylnaphthalene (1) and various tetracarboxylic dianhydrides by a conventional two-step procedure that included ring-opening polymerization in N-methyl-2-pyrrolidone and subsequent thermal cyclic dehydration. PI1x were characterized by X-ray diffraction, differential scanning calorimetry, thermogravimetry, and dynamic mechanical analysis. PI1x had glass transition temperatures in the range of 270–315°C and all PI1x were amorphous. The structure–property relationships of these PIs were examined and compared with those of polyimides (PI2x) from 4,4′-bis(4-aminophenoxy)biphenyl (2) and polyimides (PI3x) from 1,4-bis(4-aminophenyl)-2,3-diphenylnaphthalene (3). Water absorption and dielectric constants ( ε) of the PIs were also compared and discussed on the basis of imide content per repeating unit.

Aromatic polyimides (PIs) with a hexaphenylbenzene unit were synthesized from 1,4-bis[4-(4-aminophenoxy)phenyl]-2,3,5,6-tetraphenylbenzene (1) and various tetracarboxylic dianhydrides by a conventional two-step procedure that included ring-opening polymerization in N-methyl-2-pyrrolidone and subsequent thermal cyclic dehydration. The PIs were characterized by X-ray diffraction, differential scanning calorimetry, thermogravimetry, and dynamic mechanical analysis. The PIs had glass transition temperatures in the range of 289–352°C, and all the polymers were amorphous. The structure–property relationships of these PIs were examined and compared with those of the previously prepared analogous PIs from 4,4′-bis(4-aminophenoxy)biphenyl (2) and 4,4′-bis(4-amino-2-phenylphenoxy)biphenyl (3). Water absorption and dielectric constants of the PIs were also compared and discussed on the basis of imide content per repeating unit.

Interest in atmospheric aerosol issues has been increasing worldwide. X-ray fluorescence (XRF) is an important atmospheric aerosol monitoring tool for inorganic component analysis, because XRF is a rapid and easy analysis method. In particular, Energy dispersive X-ray fluorescence (EDXRF) has drawn attention for aerosol analysis. However, EDXRF has difficulties that: (1) many overlapping peaks exist for aerosol filter analysis and (2) many thin-film standard samples are required when an empirical calibration method is employed. Accurate analysis method of aerosol filter samples without the need for large sets of standards by semi-quantitative analysis software RPF–SQX (Rigaku profile fitting–spectra quant X), which includes the exact profile fitting and thin-film fundamental parameter (FP) method, is described using the EDXRF spectrometer equipped with secondary targets and polarized optics.

A Z type sexiphenyltetracarboxylic dianhydride, 3,3′′′′′,4,4′′′′′-1,1′:2′,1′′:4′′,1′′′:4′′′,1′′′′:2′′′′,1′′′′′-sexiphenyltetracarboxylic dianhydride (1), was synthesized in seven steps from diethyl 4-bromophthalate. Aromatic polyimides (PI1x) were synthesized from 1 and various aromatic diamines (x) by both a conventional two-step procedure and a one-step procedure, and the properties were compared with those of the polyimides (PI2x) previously prepared from rigid 3,3′′′′′, 4,4′′′′′-p-sexiphenyltetracarboxylic dianhydride (2), the isomer of 1. The values of glass transition (Tg) temperatures are much higher (270–345 °C) than those of the corresponding PI2x, and the decrease in the storage modulus at Tg is larger than that of the corresponding PI2x.

Ni(0)-catalyzed coupling polymerizations of 3,6-di(4-chlorophenyl)-3,6-dihydrophthalic acid diethyl ester 1 were accompanied by isomerization of the 1,4-cyclohexadiene moiety into a 3,5-cyclohexadiene group, yielding a conjugated polymer. The structure of this conjugated polymer was the same as that of the conjugated polymer from 3,6-di(4-chlorophenyl)-1,2-dihydrophthalic acid diethyl ester 2. The number-average degree of polymerization was only ∼7 due to the low solubility of the conjugated polymer. The conjugated polymer exhibited a λ max at 430 nm in the absorption spectrum, and could be applied as a photo-sensitizer of a solar cell. The incident monochromatic photon (450 nm)-to-current conversion efficiencies of photocurrent from an indium-titanium oxide (ITO)/TiO2 electrode modified with the conjugated polymer was 6.1% in the I3−-3I− electrolyte wet system. The conjugated polymer exhibited a glass transition temperature of 210 °C and was converted by thermal treatment at 300 °C to poly(p-phenylene) (PPP) with the elimination of ethoxycarbonyl groups. Ni(0)-catalyzed coupling polymerizations of 3,6-di(4-chlorophenyl)-3,6-dihydrophthalic acid diethyl ester 1 were accompanied by isomerization of the 1,4-cyclohexadiene moiety into a 3,5-cyclohexadiene group, yielding a conjugated polymer. The structure of this conjugated polymer was the same as that of the conjugated polymer from 3,6-di(4-chlorophenyl)-1,2-dihydrophthalic acid diethyl ester 2. The conjugated polymer exhibited a λ max at 430 nm in the absorption spectrum, and could be applied as a photo-sensitizer of a solar cell. The incident monochromatic photon (450 nm)-to-current conversion efficiencies of photocurrent from an ITO/TiO2 electrode modified with the conjugated polymer was 6.1% in the I3--3I- electrolyte wet system.

Hyperbranched poly(ether ether ketone)s with hydroxyl terminal groups are prepared by a one-step polycondensation of 3,5-dihydroxy-4′-(4-fluorobenzoyl)diphenylether (AB2-type monomer) through an aromatic nucleophilic substitution reaction. With the help of model compounds, 1H-NMR studies reveal that the degree of branching of the poly(ether ether ketone)s is about 52%. The possibility of entanglement among the hyperbranched polymer molecules is suggested from comparison of their glass transition temperatures with the corresponding dendrimers and the optimized structure of the hyperbranched polymers. The terminal hydroxyl groups were readily functionalized, yielding hyperbranched polymers with a variety of different functional chain ends. The nature of the chain end is shown to dramatically affect the properties of the hyperbranched polymers. Hyperbranched poly(ether ether ketone)s with hydroxyl terminal groups were prepared by a one-step synthesis of an AB2-type monomer 3,5-dihydroxy-4′-(4-fluorobenzoyl)diphenylether through an aromatic nucleophilic substitution reaction. The degree of branching determined by 1H-NMR analysis was about 52%. The reduced viscosities of the hyperbranched polymers were higher than those of the corresponding dendrimers, the glass transition temperatures of the hyperbranched polymers were higher than those of the dendrimers and the existence of entanglement among the hyperbranched polymer molecules was suggested.

Diamines, namely, 1,4-bis(4-amino-2-phenylphenoxy) benzene (1) and 4,4′-bis(4-amino-2-phenylphenoxy) biphenyl (2), were synthesized from 4-fluoro-3-phenyl nitrobenzene. Two series of polyimides were synthesized from these diamines with nine types of dianhydrides by a conventional two-step procedure that included ring-opening polymerization in N-methyl-2-pyrrolidone and subsequent thermal cyclic dehydration. The polyimides were characterized by x-ray diffraction, differential scanning calorimetry, thermogravimetry and dynamic mechanical analysis. The polyimides from 1 and 2 had a glass transition temperature in the range of 221–254°C and 222–271°C, respectively, and all the polymers were amorphous. The structure–property relationships of these polyimides were examined and compared with those of the previously prepared analogous polyimides from the bis(4-amino-2-biphenyl)ether (3). Water absorption and dielectric constants ( ∊) of the polyimides were compared and discussed on the basis of imide content per repeating unit.

New polyimide–silica hybrid materials were prepared using the polyamic acid synthesized by copolymerization of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), 4,4′-oxydianiline (ODA) and an A 2 A′-type tri-functional amine, 1,1-bis(4-(aminophenoxy)phenyl)-1-(4-(4-amino-2-trifluoromethylphenoxy)phenyl)ethane (1) (BTDA:ODA:1 = 7:6:1 in the molar). 3-(Triethoxysilyl)propyl succinic anhydride(TESSA) was reacted with amino groups in polyamic acid to introduce ethoxysilyl moiety which act as conjugation site for silica. The polyimide–silica hybrid films were prepared by a sol–gel reaction of tetraethoxysilane (TEOS) in a solution of the polyamic acid, followed by thermal imidation. Self-standing films were obtained with up to 50 wt.% silica, and transparent films were obtained at up to 40 wt.% silica. Dynamic-mechanical and mechanical analyses were carried out to examine the properties of hybrid films.

A new diamine, 1,1-bis[4-(4-aminophenoxy)phenyl]-1-(4-hydroxyphenyl)ethane, was synthesized in three steps starting from 1,1,1-tris(4-hydroxyphenyl)ethane. New aromatic polyimides having hydroxy side groups were prepared from this diamine and various tetracarboxylic dianhydrides by the conventional two-step procedure that included ring-opening polymerization in N-methyl-2-pyrrolidone (NMP) and subsequent thermal cyclic dehydration. The polyimides were characterized by X-ray diffraction, differential scanning calorimetry (DSC), thermogravimetry (TG), and dynamic mechanical analysis (DMA). All the polyimides were amorphous, and had glass transition temperature ( Tg) in the range of 232—304 °C. The properties of polyimides were compared with those of polyimides prepared from 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenylethane, which had no hydroxy side groups. The effects of the hydroxy side groups were observed in the thermal properties, thermal mechanical properties and solubility of polyimides.

Aromatic polyimides, which had trifluoromethyl group at 2,2′-position of the diphenyl ether, were synthesized from bis(4-amino-2-trifluoromethylphenyl)ether (1) and previously prepared tetracarboxylic dianhydrides, 3,3′′′,4,4 ′′′- p-quaterphenyltetracarboxylic dianhydride (2d), 3,3′′′ ′,4,4′′′ ′- p-quinquephenyltetracarboxylic dianhydride (2e) and 3,3′ ′ ′ ′ ′ ,4,4 ′ ′ ′ ′ ′ - p-sexiphenyltetracarboxylic dianhydride (2f), and the properties were compared than those of corresponding polyimides from commercially available tetracarboxylic dianhydrides. The polyimides were synthesized by the conventional two-step procedure of ring-opening polyaddition in N-methyl-2-pyrrolidinone (NMP) and subsequent thermal cyclic dehydration. The polyimides were characterized by differential scanning calorimetry (DSC), thermogravimetry, and dynamic mechanical analysis (DMA). The polyimides showed excellent thermal stability, and had glass transition temperature ( Tg) at 234—300 °C. The properties of polyimides were compared with those of previously prepared polyimides, which had phenyl group at 2,2′-position of the diphenyl ether, and the effect of the trifluoromethyl groups at the 2, 2′- positions of the diphenyl ether were observed in the thermal properties, solubility and optical properties of polyimides.

During the transboundary transport of anthropogenic heavy metals by mineral particles providing reaction sites, the divalent metal salt PbSO 4 can be converted to PbCO 3 in the presence of water. We carried out laboratory experiments to study the transformation process under various conditions by incorporating test particles comprising CaCO 3 of a particulate mineral component, PbSO 4 , and NaCl. After the immersion of PbSO 4 particles in contact with CaCO 3 particles in a water droplet, the conversion of PbSO 4 into PbCO 3 was confirmed by the change in morphology of the original particles to stick or needle form; the percentages of the chemical forms relative to the total Pb were determined by X-ray absorption near edge structure (XANES) analysis. Approximately 60–80% of PbSO 4 was converted to PbCO 3 after 24 h. A small amount of stick particles was detected when NaCl particles attached to PbSO 4 /CaCO 3 particles were exposed to air with a relative humidity (RH) of 80–90% for 24 h. XANES measurements of the samples revealed that the molar percentage of PbCO 3 relative to the total Pb content was 4%. Field experiments were also conducted to determine the chemical forms of the Pb particles during the Kosa (Asian dust storm) event. Samples were collected from two remote sites in Japan and Korea. The mass size distribution of Pb aerosols collected in Japan was bimodal with two peaks in the coarse mode; the enrichment factor of Pb suggested that its source was anthropogenic. Pb L3 edge XANES measurements of both samples indicated that they had similar shapes. These measurements also indicated that the major Pb components for the samples collected in Japan were PbO, PbSO 4 PbCl 2 , and PbCO 3 , with molar percentages of 44%, 30%, 21%, and 5%, respectively. No significant differences were found between the component ratios of the samples collected in Japan and Korea, suggesting that definite transformation did not occur during the transport of the Kosa particles from Korea to Japan. On the basis of these observations, we postulate that the transformation process either occurred mainly before the particles arrived at Korea or did not take place after the particles left continental Asia.

A novel sulfonated diamine bearing aromatic sulfophenyl pendant groups, named as, 2,2′-bis(4-sulfophenyl)-4,4′-oxydianiline (SPhODA) was synthesized. Sulfonated (co)polyimides (SPIs) with flexible ether linkage in the main chain and sulfophenyl groups in the side chain were synthesized from SPhODA, 1,4,5,8-naphthalene tetracarboxylic dianhydride and nonsulfonated diamines. The SPI membranes showed good solubility in common aprotic solvents and high desulfonation temperature of 320 °C. The SPIs with ion exchange capacities of 1.57–2.50 meq g −1 displayed reasonably high proton conductivities of 0.09–0.21 S cm −1 at 60 °C in water and 0.02–0.05 S cm −1 at 70% relative humidity. They also displayed high mechanical properties, but their water stability was not enough high at high temperatures. They showed high potential for DMFC application at low and/or mediate temperatures.

The polyimides containing the hydroxy group were synthesized from 3,3 '-dihydroxybenzidine (I) and previously prepared tetracarboxylic dianhydrides, 3,3''',4,4'''- p-quaterphenyltetracarboxylic dianhydride (IId), 3,3'''',4,4''''- p-quinquephenyltetracarboxylic dianhydride (IIe) and 3,3''''',4,4'''''- p-sexiphenyltetracarboxylic dianhydride (IIf), and the properties were compared with those of corresponding polyimides from commercially available dianhydrides. The polyimides were synthesized by the conventional two-step procedure of ring-opening polyaddition in N-methyl-2-pyrrolidinone (NMP) and subsequent thermal cyclic dehydration. All the polyimides were soluble in NMP on heating. The glass transition temperature ( Tg) of the polyimides ranged from 336—360°C, and were not dependent on the structure of tetracarboxylic dianhydride. The storage modulus of some polyimides did not decrease at high temperature. All the polyimides underwent thermal conversion to polybenzoxazoles upon heating to 500°C for 1 h under vacuum. The thermal conversion of the polyimides to polybenzoxazoles was confirmed by Fourier transform infrared spectrometry. The 10% weight loss temperature ( T10) of the polybenzoxazoles was 530—700°C in nitrogen, and the polybenzoxazoles were thermally stable. In particular, the T10 values of the polybenzoxazoles from IId, IIe, and IIf were above 630°C.

Aromatic polyimides having phenyl groups at the 2- and 2′-positions of the diphenyl ether moiety were synthesized from bis(4-amino-2-biphenyl) ether and various tetracarboxylic dianhydrides by the conventional two-step procedure using N-methyl-2-pyrrolidone (NMP) as a solvent [Morikawa et al., Polymer Journal37, 759, 2005]. The phenyl groups at the 2,2′-position of the phenyl ether improved the solubility of polyimides without decreasing the thermal and thermo-mechanical properties. In this paper, soluble polyimides were synthesized in a one-step procedure by reacting this diamine with various tetracarboxylic dianhydrides in m-cresol at 190°C, and the properties, especially the thermal properties, thermo-mechanical properties and solubility were compared with those of the polyimides synthesized by the two-step procedure.

A new phenylated diamine, bis(4-amino-2-biphenyl)ether, was synthesized in five steps starting from 3-chloro-4-fluoronitrobenzene. New aromatic polyimides having phenyl groups at the 2- and 2′-positions of the diphenyl ether moiety were prepared from this diamine and various tetracarboxylic dianhydrides by the conventional two-step procedure that included ring-opening polymerization in NMP and subsequent thermal cyclic dehydration. The polyimides were characterized by differential scanning calorimetry (DSC), thermogravimetry, and dynamic mechanical analysis (DMA). Typical polyimides showed excellent thermal stability, and had glass transition temperature (Tg) above 250 °C. As for the series of polyimides prepared from tetracarboxylic anhydrides having linear phenylene moiety, the introduction of phenyl group at the 2- and 2′-positions of phenyl ether improved thermal and thermo-mechanical properties as well as the solubility of polymers.

We have prepared aromatic polyimides PI-Ar- m containing p-quarterphenyl ( m = 2) and p-sexiphenyl ( m = 4) units. [ILLEGIBLE] These polyimides are characterized by having long phenylene units and the introduction of these has a strong influence on the properties of polyimides. In this paper, the properties of polyimides are compared with those of polyimides from 3,3″,4,4″- p-terphenyltetracarboxylic dianhydride ( m = 1) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride ( m = 0), which had been previously prepared, and discussed on the basis of the number ( m) of phenylene units in the dianhydrides.

A new rigid tetracarboxylic dianhydride, 3,3''''',4,4'''''-p-sexiphenyltetracarboxylic dianhydride, was synthesized in seven steps starting from diethyl 4-bromophthalate. New aromatic polyimides containing a p-sexiphenyl unit were synthesized from this tetracarboxylic dianhydride and various aromatic diamines by the conventional two-step procedure of ring-opening polyaddition in a polar amide-type solvent and subsequent thermal cyclic dehydration. These polyimides had inherent viscosities of 1.20—1.69 dL g-1, and were insoluble in organic solvents. The polyimides were characterized by differential scanning calorimetry (DSC), thermogravimetry (TG), wide-angle X-Ray diffraction measurements, and dynamic mechanical analysis (DMA). Typical polyimides were noncrystalline and showed excellent thermal stability, and had glass transition temperatures (Tg) at about 250°C. Decrease in the modulus at the glass transition temperature was less than corresponding polyimides having no p-sexiphenyl unit due to the presence of the rigid p-sexiphenyl unit.

New highly branched poly[(ether)-(ether ether ketone)] dendrimers were synthesized by the convergent approach using two building blocks, 3, 5-dihydroxybenzyl alcohol, 1, and 3, 5-dihydroxy-4′-(4-fluorobenzoyl)diphenylether, 2, alternatively. The reaction of p-fluorobenzonitrile and 1 gave 3, 5-di(4-cyanophenoxy)benzylalcohol (the first generation dendron, G1-OH). After G1-OH was converted to 3, 5-di(4-cyanophenoxy)benzylbromide (G1-Br), the resultant benzylic bromide functionality was allowed to react with 2 to yield the second-generation dendron (G2-F). The third-generation dendron (G3-OH) was obtained by the reaction of G2-F and 1, and the fourth-generation dendron (G4-F) was obtained by reaction of G3-Br derived from G3-OH, with 2. Finally, dendrimers, Den-(G2)3 and Den-(G4)3 were synthesized by reaction of G2-F and G4-F with trifunctional core, respectively. Analysis was made of these structurally unambiguous dendrons and dendrimers by gel permeation chromatography (GPC) and matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectroscopy. 1H and 13C NMR spectra were consistent with the structures of these dendrons and dendrimers.

New highly branched poly(ether ether ketone) dendrimers were synthesized by the divergent approach through aromatic nucleophilic substitution reactions. 3,5-Dimethoxy-4'-(4-fluorobenzoyl)diphenylether, 1, and 1,3,5-tris[p-(3,5-dihydroxyphenoxy)phenyl]benzene, G0-OH, were used as a building block and starting core, respectively. The reaction of 1 with G0-OH gave the first-generation dendrimer (G1-OMe), which possessed 12 methoxy groups on the periphery. After the methoxy groups were converted to hydroxy groups by treatment with pyridine hydrochloride, the resultant phenol functionality (Gl-OH) was allowed to react with 1 to yield the second-generation dendrimer (G2-OMe) which possessed 24 methoxy groups. By repeating these procedures G3-OMe dendrimer and G3-OH dendrimer possessing 48 methoxy and hydroxy groups, respectively, on the periphery were obtained. 1 H and 13 C NMR spectra were consistent with the structures of these dendrimers. Molecular weights and molecular weight distribution determined by gel permeation chromatography indicated that the dendrimers possessed remarkably narrow molecular weight distribution. Analysis was made of these structurally unambiguous dendrimers by matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectroscopy. The characteristics of these dendrimers, Gn-OMe and Gn-OH, such as solubility and thermal properties were compared.

New highly branched poly(ether ketone) dendrons, with graded structures, were synthesized by the convergent approach using aromatic nucleophilic substitution reactions. Four kinds of compounds3,5-bis(4-fluorobenzoyl)anisole, 1; 4-methoxy-3‘,5‘-bis(4-fluorobenzoyl)-biphenyl, 2; 4-methoxy-3‘ ‘,5‘ ‘-bis(4-fluorobenzoyl)-p-terphenyl, 3; and 4-methoxy-3‘ ‘‘,5‘ ‘‘-bis(4-fluorobenzoyl)-p-quaterphenyl, 4(numberedin the order of the phenylene length) were used as the building blocks, where the methoxy groups were the protected form of hydroxy groups. The reactions of 1 with phenol gave the first generation dendron, G1. Next, after the methoxy group of G1 was converted to the hydroxy derivative, G1−OH by the reaction with aluminum chloride, the resultant phenol functionality of G1−OH was allowed to react with 2 to yield the second generation dendron: G2. By repeating the procedure, further generations G3 and G4, were prepared using 3 and 4 as the building block, respectively. The 1H and 13C NMR spectra were consis...

A new highly phenylated diamine, 1,4-bis(4-aminophenyl)-2,3-diphenylnaphthalene, was synthesized in two steps starting from 2,5-bis(4-nitrophenyl)-3,4-diphenylcyclopentadienone. New aromatic polyamides containing tetraphenylnaphthalene unit were prepared by low temperature solution polycondensation of this diamine with various aromatic dicarboxylic acid chlorides. These polyamides had inherent viscosities of 0.45—0.82 dlg−1. Polyamides with m-phenylene moiety and flexible connecting group were soluble in various organic solvents such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone, but those with rigid symmetric structures were soluble in only hot N,N-dimethylacetamide and N-methyl-2-pyrrolidone. The glass transition temperature of the polyamides ranged from 268 to 366°C, and the 10% weight loss temperatures were above 500°C in air.

New AB2 type monomers, with a various number of phenylene units, were prepared and converted to hyperbranched poly(ether ketones) by polymerization. Four kinds of AB2 type monomers, 4-hydroxy-3‘,5‘-bis(4-fluorobenzoyl)-biphenyl, 1, 4-hydroxy-3‘‘,5‘‘-bis(4-fluorobenzoyl)-p-terphenyl, 2, 4-hydroxy-3‘‘‘,5‘‘‘-bis(4-fluorobenzoyl)-p-quarterphenyl, 3, and 4-hydroxy-3‘‘‘‘,5‘‘‘‘-bis(4-fluorobenzoyl)-p-quinquephenyl, 4, were synthesized in a stepwise manner starting from 3,5-bis(4-fluorobenzoyl)phenol, 5, repeating a series of conversions of the hydroxy group to the triflate, cross-coupling reaction of the triflate with (p-methoxyphenyl)boronic acid, and cleavage of the methyl ether. Four kinds of hyperbranched poly(ether ketones) were prepared by the polymerization of the four AB2 type monomers. Obtained hyperbranched poly(ether ketones) from 1 and 2 were soluble in various organic solvents including N-methyl-2-pyrrolidone, m-cresol, chloroform, and tetrahydrofuran, but those from 3 and 4 were insoluble in organi...

Timing synchronization is essential in case where multiple sensor nodes with ultrasonic sensors are deployed on the same place. This is because the ultrasonic sensors should be powered at an appropriate timing so as to prevent ultrasonic interference. In this paper, we propose a new timing synchronization method for ZigBee sensor network for ecology observation. In this method, a sensor node has been configured as a ZigBee router in order to exchange time information among nodes in real-time. Moreover, by concentrating the processing load to the server, the amount of calculation at each node can be minimized and is unaffected by the increase in nodes. By using the proposal method, it is concluded that the time synchronization should be executed per every few minutes in order to detect moving objects by the ultrasonic sensors.

1. Overview Recently, diesel engine has been improving its environmental performance. However, it is still difficult for the diesel engine to adopt the strengthening of emission regulation and various kinds of diesel fuels simultaneously. Thus, we have developed on injection system to automatically compensate over the course of its lifetime, which is called i-ART (Intelligent Accuracy Refinement Technology), and adopted IMV (Innovative International Multi-purpose Vehicle) diesel engine (KD model) for Brazil. This engine equipped with the i-ART has successfully passed a new emission regulation and is compatible with the various kinds of diesel fuels used in Brazil.

Chiral phenylindanediamnine (+)-2 was synthesized starting from chiral phenyl-indanedicarboxylic acid by a Schmidt rearrangement. Ordered amine-acid AB-type monomers, 8 and 9, were also prepared by a controlled reaction of (+)-2 with diacid chlorides. Disordered and ordered polyamides were synthesized by the reaction of (+)-2 with dicarboxylic acids, and the self-condensation of 8 and 9, respectively. Both the ordered and disordered polyamides were soluble in various solvents. The polyamides composed of the same dicarboxylic acid prepared by the different routes showed the same circular dichroism spectra. X-ray diffraction of the polyamide films indicated that all of the polyamides were amorphous. The glass transition and decomposition temperatures ranged from 170 to 340°C and from 320 to 400 °C, respectively. Additionally, polyamides containing the same diacids displayed nearly equivalent physical properties.

A simple and rapid method for the simultaneous determination of serum nicotine and cotinine using high-performance liquid chromatography (HPLC)-fluorometric detection with a postcolumn ultraviolet-photoirradiation system was developed. Analytes were extracted from alkalinized human serum via liquid-liquid extraction using chloroform. The organic phase was back-extracted with the acidified aqueous phase, and the analytes were directly injected into an ion-pair reversed-phase HPLC system. 6-Aminoquinoline was used as an internal standard. Nicotine, cotinine, and 6-aminoquinoline were separated within 14min. The extraction efficiency of nicotine and cotinine was greater than 91%. The linear range was 0.30-1000ng for nicotine and 0.06-1000ng for cotinine. In serum samples from smokers, the concentrations of nicotine and cotinine were 8-15ng/mL and 156-372ng/mL, respectively.

An optically pure isomer of 1,l,3.-trimethyl-3-phenylindane-4',5-dicarboxylic acid (PIDA) was obtained by introduction of racemric PIDA to a diester of the optically pure alcohol. D-(-)-pantolactone, followed by hydrolysis of the separated stereoisomer of the diester. Optically active aromatic polyamides (aramids) were synthesized by the reaction of the optically pure PIDA with various aromatic diamines. The specific rotations of these aramids ranged from + 284 to +4416. The aramids were soluble in organic solvents such as N,N-dimethylacetamide, pyridine and m-cresol. These materials had glass transition temperatures over 290 'C, and did not decompose below 380 C. The solubility and thermal behaviour were almost the same as those of the racemic aramids. The optically active aramids were examined as a stationary phase for chromatographic enantioseparation. When the aramid derived from p-phenylenediamine was used for this purpose, the stereoisomers of l-phenylethylamine could be easily separated.