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51.
A high-performance affinity chromatographic system was constructed and shown to permit highly reproducible, rapid, automatic assays of serum glycated albumin (GA) by separation of albumin (Alb) on an anion-exchange column (Asahipak ES-502N) packed with a vinyl alcohol copolymer bearing diethylamino groups and consecutive separation of GA on a column packed with a vinyl alcohol copolymer bearing boronate groups. The first column selectively retained Alb free of other serum proteins and permitted at least a 95% recovery of sample Alb. The purity of the Alb peak was confirmed by two-dimensional electrophoresis. Chromatographic analyses of human serum Alb incubated with glucose on the second column showed that the peak area for GA increased in accordance with the incubation time and suggested selective adsorption of GA on the second column. Optimization of the conditions for the two-column system reduced the analysis time to 10 min. Analyses of human sera with the present system showed GA to be 16.1 +/- 1.1% (mean +/- S.D.) of total Alb in non-diabetic children and 39.9 +/- 9.1% (mean +/- S.D.) in diabetic children (0-17 years old).  相似文献   
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IntroductionTheturbulenceiscomposedfromdifferentscaleeddies[1].Theturbulenttransportsofmomentum,heatandcontentcausedbythedifferentscaleeddieswillbeverydifferentandtheinteractionofdifferent[2]scaleeddiesexists.Inthecenteroftheearthquake,theexcitationofthestronggroundmotionistightlyrelatedtotherandomsmallscale[3]fractures.Similarly,thelargescalefluctuationsinheterogeneousatmospherearetightlyrelatedtothesmallscalefluctuations.Inthispaper,thegloballyturbulentauto-correlationfunctionwhichobeysthep…  相似文献   
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A sensitive non-enzymatic glucose electrochemical biosensor (Cu/PMo12-GR/GCE) was developed based on the combination of copper nanoparticles (CuNPs) and phosphomolybdic acid functionalized graphene (PMo12-GR). PMo12-GR films were modified on the surface of glassy carbon electrode (GCE) through electrostatic self-assembly with the aid of poly diallyl dimethyl ammonium chloride (PDDA). Then CuNPs were successfully decorated onto the PMo12-GR modified GCE through electrodeposition. The morphology of Cu/PMo12-GR/GCE was characterized by scanning electron microscope (SEM). Cyclic voltammetry (CV) and chronoamperometry were used to investigate the electrochemical performances of the biosensor. The results indicated that the modified electrode displayed a synergistic effect of PMo12-GR sheets and CuNPs towards the electro-oxidation of glucose in the alkaline solution. At the optimal detection potential of 0.50 V, the response towards glucose presented a linear response ranging from 0.10 μM to 1.0 mM with a detection limit of 3.0 × 10−2 μM (S/N = 3). In addition, Cu/PMo12-GR/GCE possessed a high selectivity, good reproducibility, excellent stability and acceptable recovery, which indicating the potential application in clinical field.  相似文献   
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Electronic excitation spectra of the radical anions of cyanoethylenes (trans-dicyanoethylene and tetracyanoethylene) and cyanobenzenes (1,2-dicyanobenzene: o-DCNB, 1,3-dicyanobenzene: m-DCNB, and 1,4-dicyanobenzene: p-DCNB) were studied by the symmetry adapted cluster-configuration interaction (SAC-CI) method. Theoretical calculations predicted positive electron affinities for all the molecules in good agreement with the experimental observations. Electronic excitation spectra of open-shell radicals is a topic that has not been studied as much as such spectra of closed-shell molecules, but this can be easily addressed using SAC-CI theory. The present paper systematically describes the calculation procedures for radical anions by investigating several basis sets, including anion diffuse and Rydberg functions. The calculated excitation energies were in good agreement with the experimental UV∕NIR (near infrared region) spectra, which had been observed by one of the present authors in 2-methyltetrahydrofuran matrix frozen to transparent glassy solids at 77 K. For p-DCNB, the SAC-CI theoretical spectrum agreed particularly well with the experimental spectrum. An extremely weak π*(SOMO) - π* excitation at 1.41 eV predicted in the present work, but had been overlooked in the previous experimental spectrum published in 1988, was confirmed to be real by a careful re-examination of the old spectrum.  相似文献   
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We study the local change of the generalized index, which is a modification of the Morse index and the stationary index, for the multiparametric optimization. Under the Regular Value Condition, the change of the generalized index around a triplet (x,v,t) is locally bounded by the dimension of the parameter vector t, where x is a variable vector and v a vector of the Lagrange multiplier space. We also discuss the local change of the generalized index around a pair (x,t). Received: March 27, 1998 / Accepted: January 29, 2000?Published online April 20, 2000  相似文献   
58.
In this paper a new type element that can implement perfect shuffle (PS) network of free spatial optical interconnection is presented. It is a microoptics array element consisting of a series of sub-blazed gratings with different spatial frequency. The array has highly efficient light energy and a very simple setup. It can realize 1-D, 2-D PS networks and their inverse transforms. Also, the array can conveniently realize microminiaturization and multilevel interconnection and other forms of interconnections.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994.  相似文献   
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An efficient divergent synthesis of L-sugars and L-iminosugars from D-sugars is described. The important intermediate, delta-hydroxyalkoxamate, prepared from D-glucono-/galactono-1,5-lactone, was cyclized under Mitsunobu conditions to give the O-cyclized oxime compound and the N-cyclized lactam compound as mixtures. A more detailed investigation revealed that the appropriate protecting groups and solvents controlled the specificity for the O-/N-cyclization of the delta-hydroxyalkoxamate. Suitable protection at the 6-position of delta-hydroxyalkoxamate, derived from D-glucono-1,5-lactone, afforded the corresponding O-alkylation product alone. Thus we succeeded in applying this to the total synthesis of L-iduronic acid. In contrast, with both TBDMS as the protecting group and RCN as the solvent the efficient conversion of D-glucono/galactono-1,5-lactone into the corresponding L-iminosugars (L-idonolactam and L-altronolactam) was achieved.  相似文献   
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