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191.
Ohya  T.  Takeda  J.  Sato  M. 《Hyperfine Interactions》2004,159(1-4):265-268
The alignment correlation term in the β-decay angular distribution from purely nuclear spin aligned 20Na has been measured for the first time. The final objective is to test the G parity symmetry, one of the fundamental symmetry in the weak nucleon current. For artificial creation of the alignment, the knowledge of the hyperfine interaction of 20Na implanted in a single-crystal ZnO was utilized. *Research Abroad, Japan Society for the Promotion of Science  相似文献   
192.
A simple and highly sensitive spectrophotometric method for the determination of uric acid (UA) was established based on fading of the o-hydroxyhydroquinonephthalein-palladium(II)-hexadecyltrimethylammonium complex. In the determination of UA, Beer's law is obeyed in the range of 0.01-0.20 microg ml(-1), with an effective molar absorptivity at 635 nm, the relative standard deviation being 6.5 x 10(5) dm(3) mol(-1) cm(-1) and 1.5% (n = 5). This method is about 20-times more sensitive than the conventional methods. The method was successfully applied to the assay of UA in human urine.  相似文献   
193.
The motion of a moored floating body under the action of wave forces, which is influenced by fluid forces, shape of the floating body and mooring forces, should be analysed as a complex coupled motion system. Especially under severe storm conditions or resonant motion of the floating body it is necessary to consider finite amplitude motions of the waves, the floating body and the mooring lines as well as non-linear interactions of these finite amplitude motions. The problem of a floating body has been studied on the basis of linear wave theory by many researchers. However, the finite amplitude motion under a correlated motion system has rarely been taken into account. This paper presents a numerical method for calculating the finite amplitude motion when a floating body is moored by non-linear mooring lines such as chains and cables under severe storm conditions.  相似文献   
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195.
A novel dimethyl sulfoxide (DMSO) sensor using DMSO reductase and film electrodes was constructed. The Au and Ag electrodes were fabricated on slide glass by vacuum deposition and the application of a photolithographic technique. The micro-chamber (4 x 50 x 1 mm, volume 200 microl) was fabricated on a poly(dimethylsiloxane) (PDMS) polymer. The Pt electrode was implanted in a PDMS polymer. DMSO reductase was immobilized on a Au film electrode with bovine serum albumin (BSA)-glutaraldehyde. This sensor could determine DMSO in an unpurged aqueous solution with glucose oxidase (GOD) and catalase (CAT) for oxygen removal. The DMSO sensor showed a linear response within 1 mM DMSO with a correlation coefficient of 0.999. The detection limit was 200 microM (3sigma), and the sensitivity was 23.8 mA M(-1) cm(-2). The relative standard deviations at each concentration were within 3.6%.  相似文献   
196.
In this review, we present an overview of the technologies in colorimetric biosensors based on DNA-nanoparticle conjugates. Two types of DNA-nanoparticles aggregation assays are summarized. One of the methods relies on cross-linking of the gold nanoparticle (GNP) by hybridization. The crosslinking system was used not only to detect target DNA sequences, but also to detect metal ions or small molecules which were recognized by DNAzymes. The other method is the GNP non-crosslinking system. This approach shows high performance in the detection of single nucleotide polymorphisms. These methods do not need special equipment and open up a new possibility of point-of-care diagnoses.  相似文献   
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198.
This work demonstrates the usefulness of pulsed electron spin resonance (ESR)-based two-dimensional electron spin transient nutation (2-D ESN) spectroscopy for complete assignments of complicated fine-structure hyperfine ESR spectra including hyperfine forbidden transitions from electronic and nuclear high-spin systems. The 2-D ESN spectroscopy is termed transition moment spectroscopy as spectra are acquired as a function of transition moment instead of transition energy used in conventional spectroscopy. We have applied the novel spectroscopic technique to Eu2+ ion (S=7/2,I=5/2), which has two isotopes (151Eu [47.9%] and153Eu [52.1%]), in a CaF2 single crystal as a model system. We have completely identified the complicated fine-structure hyperfine ESR spectra by invoking the spectral simulation of the 2-D ESN spectra on the basis of transition moment analyses. The analyses are based on exact numerical calculations of the transition moments as well as a perturbation-based analytical approach combined with reduced rotation matrices for the nuclear part of the transition moment. This is the first example of the spectral simulation for 2-D ESN spectra including the hyperfine allowed and forbidden transitions in high-spin systems. In addition, we have made simulation of the fine-structure forbidden transitions, which reproduces the angular variations of the observed spectra at liquid helium temperatures.  相似文献   
199.
The purpose of this study is to clarify the chemical characterization of PM2.5 and PM10 in diesel exhaust particles (DEP). Sampling of PM2.5 and PM10 in DEP was carried out in November 1999 using an automobile exhaust testing system at the National Traffic Safety and Environment Laboratory, with a diesel truck (engine type: direct injection, displacement: 7,961 cc, carrying weight: 2,020 kg, equivalent inertia weight: 5,600 kg) placed on a chassis dynamometer. Sampling conditions included idling, constant speed of 40 km/h, M-15 test pattern and 60%-revolution/40%-load of maximum power. Samples were collected on a polycarbonate membrane filter (Nuclepore, pore size: 0.8 microm) using a MiniVol Portable Air Sampler (Airmetrics Co., Inc.). The concentrations of several elemental and ionic species in the PM2.5 and PM10 samples were determined by particle induced X-ray emission (PIXE) and ion chromatography analysis. PIXE analysis of the PM2.5 and PM10 samples revealed 15 elements, of which Na, Mg, Si, S, Cl, Ca, Fe and Zn were found to be the major components. Ionic species were Cl-, NO2-, NO3-, SO4(2-), Na+, NH4+, K+ and Ca2+. Concentrations of elements and ionic species under the sampling condition of 60%-revolution/40%-load were highest in comparison with those of the other sampling conditions. The elemental and ionic species data were compared for PM2.5 and PM10; PM2.5 concentrations were 70% or more of PM10 concentrations for the majority of elements, and concentrations of ionic species in PM2.5 and PM10 were almost identical.  相似文献   
200.
Nanosized gold clusters were developed in a gold-doped soda-lime silicate glass after X-ray irradiation followed by annealing, which provided an alternative way of forming metallic nanoclusters in glass to ion implantation. The formation of gold nanoclusters can be controlled by irradiation time or annealing time.  相似文献   
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