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1.
To improve the durability of hydrogen storage materials against surface poisoning by impurity gases, effectiveness of Pd-coating layer prepared by using a Barrel-Sputtering System was examined for ZrNi powder. The effectiveness of Pd-coating was evaluated by activation temperature, at which Pd/ZrNi poisoned by air could be activated to absorb hydrogen. Characterization of Pd-coated ZrNi (denoted as Pd/ZrNi) by scanning electron microscopy, electron probe microanalysis and X-ray diffraction showed that a uniform Pd-coating layer was formed with the barrel-sputtering system. It was found that the poisoned Pd/ZrNi sample could be activated even at 423 K to absorb hydrogen at room temperature. This exhibits remarkable contrast to bare ZrNi, which could be only activated appreciably above 1073 K. It is concluded that the Pd-coating by barrel sputtering is quite effective to avoid the effect of surface poisoning of powdery hydrogen storage materials. However, the activation at excessively high temperature resulted in the loss of high activity to absorb hydrogen. It was concluded that this phenomenon was associated with reactions between Pd and ZrNi to form PdZr and other byproducts.  相似文献   
2.
Bromelain inhibitor VI from pineapple stem (BI-VI) is a unique double-chain inhibitor with an 11-residue light chain and a 41-residue heavy chain by disulfide bonds and inhibits the cysteine proteinase bromelain competitively. The structure of BI-VI in aqueous solution was determined using nuclear magnetic resonance spectroscopy and simulated annealing-based calculations. Its three-dimensional structure was shown to be composed of two distinct domains, each of which is formed by a three-stranded antiparallel beta-sheet. Unexpectedly, BI-VI was found to share a similar folding and disulfide bond connectivities not with cystatin superfamily inhibitors which inhibit the same cysteine proteinases but with the Bowman-Birk trypsin/chymotrypsin inhibitor from soybean (BBI-I). BBI-I is a 71-residue inhibitor which has two independent inhibitory sites toward the serine proteinases trypsin and chymotrypsin. These structural similarities with BBI-I suggest that they have evolved from a common ancestor and differentiated in function during a course of molecular evolution.  相似文献   
3.
Transmission characteristics of a double-structured tank, used for high-frequency (1 MHz range) ultrasonic cleaning of semiconductor wafers and substrates, were improved by utilizing oblique incidence of ultrasonic waves. As the sound transmittivity through a plate in water varies with the angle of incidence, the bottom of the Pyrex glass inner container was slanted at the angle where strong transmission occurred. In the slant-bottom container, an intensive and uniform sound pressure distribution was measured with a polyvinylidene fluoride (PVDF) hydrophone probe. In comparison with the conventional horizontal-bottom container, it was shown that the distributions as well as amplitude of sound pressure were remarkably improved by slanting the bottom of the inner container at the proper angle  相似文献   
4.
    
Uniformly layered mixture of the succeeding members in the structure series was found in artificially layered Bi2Sr2Ca n–1Cu n O2n+4 films synthesized by a three-target sequential sputter deposition technique. The intergrowth structure was quantitatively evaluated by X-ray analysis technique. An averagedc-axis (half) unit length and a plane spacing d0-0.31 nm in the intergrowth structure are considered as a modulation wavelength and an average lattice of superlattice in the analysis. It is shown that the X-ray diffraction patterns observed in our films are in good agreement with that predicted by the superlattice model.  相似文献   
5.
We proposed a new method (;linearized method') to analyze neuroleptic ligand-receptor specific binding in a human brain using positron emission tomography (PET). We derived the linear equation to solve four rate constants, k(3), k(4), k(5), k(6) from PET data. This method does not demand a radioactivity curve in plasma as an input function to the brain, and can perform fast calculations in order to determine rate constants. We also tested the nonlinearized method including nonlinear equations which is a conventional analysis using plasma radioactivity corrected for ligand metabolites as an input function. We applied these methods to evaluate dopamine D(2) receptor specific binding of [(11)C] YM-09151-2. The value of B(max)/K(d)=k(3)/k (4) obtained by the linearized method was 5.72+/-3.1 which was consistent with the value of 5.78+/-3.4 obtained by the nonlinearized method.  相似文献   
6.
The disposition of diadenosine 5'5"'-P1,P4-tetraphosphate (Ap4A), an endogenous dinucleotide, was investigated in rats. The degradation of Ap4A in rat plasma was very rapid and could be explained by a Michaelis-Menten equation: Km and Vmax values were 1.69 micrograms/ml and 4.32 micrograms/min/ml, respectively. Ap4A was degraded in rat plasma to ATP and AMP, but not to 2 ADP molecules, and these nucleotides were further degraded through adenosine. The degradations kinetics were examined. After intravenous bolus injection, Ap4A in plasma declined rapidly and the rate of elimination was dose-dependent: the biological half-life was about 3s at the dose of 1 mg/kg and was longer at 3 mg/kg. When Ap4A was administered by intravenous infusion (0.5 or 1.0 mg/kg/min), the plasma level rapidly reached a steady-state, which then rapidly declined after stopping the infusion.  相似文献   
7.
Artificial Life and Robotics - In recent years, unspecified messages posted on social media have significantly affected the price fluctuations of online-traded products, such as stocks and virtual...  相似文献   
8.
Two hundred open heart cases anaesthetized with a combination of diazepam-ketamine using "Micro-Mini" drip administration technique were presented. The results were eminently desirable, and in the opinion of the authors are a notable improvement over other methods for all types of cardiovascular surgery including most advanced heart diseases. The advantages of this anaesthetic method for cardiovascular surgery are as follows: 1. Effects on cardiovascular system are minimal.--2. Respiratory depression is negligible.--3. There is no increase in salivation or muscle tone.--4. Induction and maintenance of anaesthesia are simple and smooth.--5. Anaesthesia can be maintained, using a high concentration of oxygen alone, by a slight increase in rate of ketamine administration whenever necessary.--6. Post-anaesthetic psychotomimetic effects are negligible.--7. Nearly 100% of patients have excellent amnesia.--8. It has a wide margin of safety.--9. This technique has proved highly acceptable to patients and surgeons. We feel ketamine should be used in small dosages continuously administered with either "Micro-Mini" drip infusion or infusion pump. Ketamine given in this fashion should be regarded as an analgesic.  相似文献   
9.
Two hundred open-heart cases were anaesthetized with a diazepam-ketamine combination. The results were excellent. A "Micro-Mini" drip technique insured low, even, but adequate dose levels of ketamine and less drug was used. Induction and maintenance are simple and smooth. Effects on the cardiovascular system and respiratory system are minimal. The margin of safety is wide and 100% oxygen can be used whenever needed.  相似文献   
10.
The deuterium trapping behaviors in tungsten damaged by light ions with lower energy (10 keV C+ and 3 keV He+) or a heavy ion with higher energy (2.8 MeV Fe2+) were compared by means of TDS to understand the effects of cascade collisions on deuterium retention in tungsten. By light ion irradiation, most of deuterium was trapped by vacancies, whose retention was almost saturated at the damage level of 0.2 dpa. For the heavy ion irradiation, the deuterium trapping by voids was found, indicating that cascade collisions by the heavy ion irradiation would create the voids in tungsten. Most of deuterium trapped by the voids was desorbed in higher temperature region compared to that trapped by vacancies. It was also found that deuterium could accumulate in the voids, resulting in the formation of blisters in tungsten.  相似文献   
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