摘要:

AbstractThe synthesis and mesomorphic properties of a homologous series of N‐(3‐hydroxypropyl)‐4‐alkoxylsalicylaldimine, N‐(3‐hydroxypropyl)‐4‐(4′‐alkoxybenzoxy)salicylaldimine, and their dicopper(II) and di‐oxovanadium(VI) complexes are reported. Copper complexes exhibited monotropic smectic A phases; however, vanadyl complexes showed no mesomorphism. A systematic comparison revealed that the meso‐genie behaviors of these bimetallic complexes are induced by the weak intermolecular force and determined mainly by the central metal. The effects on the structural variations near the metal central cores and side chain den

ISSN:0009-4536    

DOI:10.1002/jccs.199700014

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractStudies of the 410band of the Ã1A2X̃1A1transition of thioformaldehyde by means of intermodulated fluorescence and microwave‐optical double resonance have revealed numerous small perturbations in the excited state levels caused by high rovibronic levels of the ground state. Singlet‐triplet perturbations have been studied by the same techniques and also by anticrossings produced in the presence of a magnetic field. The use of microwave‐optical double resonance for studying collisional processes is di

ISSN:0009-4536    

DOI:10.1002/jccs.199700015

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractThe spectral features of satellite holes are used to investigate 9‐aminoacridine‐DNA interactions. The hole depths of the outer ring vibronic modes are reduced more than that of the inner ring vibronic modes, implying that inner ring motion is less perturbed than outer ring motion. As a result, the mode coupling between the inner ring and outer ring is reduced upon binding to DNA. However, similar hole frequency and width of the satellite hole corresponding to the NH2mode upon binding to DNA imply that the amino group of 9‐aminoacridine sits outside th

ISSN:0009-4536    

DOI:10.1002/jccs.199700016

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractCapillary zone electrophoresis with end‐column amperometric detection at a copper microdisk electrode (100 μm in diameter) was successfully applied for simultaneous determination of carbohydrates and amino acids. Under the separation voltage of 27 kV and the separation electrolyte of 80 mM NaOH in a 75 cm fused silica capillary (10 μm i.d. × 375 μmU o.d.), complete separation of a standard mixture containing 9 carbohydrates and 12 amino acids was achieved in less than 25 min. With the electrokinetical injection of 5.4 s at 27 kV and the detection potential of 0.62 V vs. Ag/AgCl, the detection limits (S/N = 3) were 0.22–0.65 ppm (1.2–1.9 μM) for carbohydrates and 0.31–6.5 ppm (2.3–39 μM) for amino acids, respectively. The calculated numbers of theoretical plates were between 41,000 and 190,000. The use of this method for analysis of carbohydrates and amino acids in a urine sample w

ISSN:0009-4536    

DOI:10.1002/jccs.199700017

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractGas chromatography using flameless sulfur chemiluminescence detection was applied to the analysis of sulfur compounds in air. A trap employing the solid adsorbent Tenax GR was used to enrich ambient levels of volatile sulfur compounds. The sulfur gases were then thermally released according to programmed temperature from the adsorbent trap and re‐collected in a column cooled with liquid nitrogen. The sulfur compounds were revolatilized and directly transferred to the system of PLOT‐column gas chromatograph/flameless sulfur chemiluminescence detector for analysis. The PTV injector has been used as a thermal resorption chamber for analysis of sulfur compounds. The sulfur gaseous compounds known to cause nuisance odors in the air from sewerage treatment works were determi

ISSN:0009-4536    

DOI:10.1002/jccs.199700018

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractThe purpose of this investigation is to try and understand the degree of arsenic poisoning in the waste water from agricultural chemical factories which release effluents into the waterways in their vicinity. The method of determination is to use the water samples, soil, fish, clams, shell‐fish, etc. found in the areas along the canals and aqueducts and those which lie upstream, midstream, and downstream and also the hair samples of people living in the contiguous areas, to check for the levels of arsenic in them by emission spectroscopy.From the analysis during a one year investigation, we find that the level of As in the water creatures of Chungkang Stream and Lu‐Er‐Men Stream is much higher than in the other water areas of Taiwan such as along beaches and the other rivers; the levels in the hair of the people who live nearby these water courses have a certain degree of correspondence with their eating habits and the quantity of food eaten; however, even those people who eat relatively little have almost 3% As, beyond the 2 mg/kg limit allowed for human beings. We are fully aware of the high level of food contamination on Taiwan, and this fact has been taken into consideration. The effect of As contamination in the soil on agricultural produce does not seem to have any apparent relationship. By the way, the influence of the monthly average rainfall on As contamination in the soil is not ob

ISSN:0009-4536    

DOI:10.1002/jccs.199700019

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractThe new bis(amide) derivatives of DTPA (diethylenetriamine‐N,N,N′,N″,N″‐pentaacetic acid), diethylenetriamine‐N,N′,N″‐triacetic‐N,N″‐bis(benzylamide) (DTPA‐BBA) have been synthesized. The crystal structure of gadolinium(III) complex of DTPA‐BBA ([Gd(DTPA‐BBA)]) has been determined by X‐ray crystallography: C28H52GdN5O17, Mw= 889 g mol−1, space group\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm P}\bar 1 $\end{document}(#2) (triclinic), a = 12.645(4), b=14.125(8), c = 12.623(4) Å, α = 111.60(3), β = 114.79(3), γ = 88.39(4)°, V = 1881(1) Å3, Z = 2, Dx= 1.569 g/cm3, λ(Mo Kα) =0.71069 Å, μ = 18.44 cm−1, final R = 0.047, Rw= 0.046 for 3755 independent observed reflections at 23 °C. The coordination sphere of Gd(III) comprises three amine nitrogens, two amide oxygens, three carboxylic acid oxygens, and one water. The relaxivity of Gd(III) complex was determined to be R1 = 4.08(4) and R2 = 6.06(5) dm3mmol−1s−1at pH = 7.0, 20 MHz, and 37(1) °C. Additionally, the R1 relaxivity for Gd(III) chelate was found to be invariant with respect to pH changes over the range of 2‐10. This indicates that a constant inner‐sphere hydration number is associated with the [Gd(DTPA‐BBA)] complex

ISSN:0009-4536    

DOI:10.1002/jccs.199700020

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractThe mass spectra of a series of substituted butenolides were studied. Their fragmentations in the mass spectrometer strongly depend upon the nature of the substitutents. The fragment's ions include the lactone skeletons, substituents, and resultant derived from the loss of a carbon dioxide from lactone.

ISSN:0009-4536    

DOI:10.1002/jccs.199700021

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractA new bondset for cortical steroid synthesis is developed from the dual concepts of convergent assembly and multiple construction. A short synthesis on this bondset is presented in which the final bond construction by electrocyclization took an unwanted course. Stereocontrol is discussed separately.

ISSN:0009-4536    

DOI:10.1002/jccs.199700022

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractChiral separation of reduced haloperidol (RHP), an optically active metabolite from haloperidol, by capillary electrophoresis is described. RHP was separated on an uncoated capillary with dimethyl‐β‐cyclodextrin (dimethyl‐β‐CD) in Tris phosphate buffer using PEG 6000 as an organic additive. Several parameters affecting the separation of RHP were studied, including pH and concentration of buffer, buffer additive, and concentration of chiral selector. The migration order of the resolved RHP was assigned with reference RHP en

ISSN:0009-4536    

DOI:10.1002/jccs.199700023

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY