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21.
Streptomyces sp Mo endo‐β‐1,3‐glucanase was found to have hydrolyzing activity toward curdlan and released laminarioligosaccharides selectively. The molecular weight was estimated to be 36000 Da and its N‐terminal amino acid sequence was VTPPDISVTN. The optimal pH was 6 and the enzyme was found to be stable from pH 5 to 8. The optimal temperature was 60 °C and the activity was stable below 50 °C. The enzyme hydrolyzed selectively curdlan containing only β‐1,3 linkages. The enzyme had 89% relative activity toward Laminaria digitata laminarin, which contains a small amount of β‐1,6 linkages compared with curdlan, while Eisenia bicyclis laminarin with a higher amount of β‐1,6‐linkages, was not hydrolyzed. Mo enzyme adsorbed completely on curdlan powder. The enzymatic hydrolysis of curdlan powder resulted in the accumulation of laminaribiose (yield 81.7%). Trisaccharide was inevitably released from the hydrolysis of laminarioligosaccharides with 5 to 7 degrees of polymerization (DP). Although the enzyme cleaved off disaccharide (DP 2) from tetrasaccharide (DP 4), the reaction rate was lower than those of DP 5 to 7. The results indicated that the active site of Mo endo‐β‐1,3‐glucanase can efficiently recognize glucosyl residue chain of greater than DP 5 and hydrolyzes the β‐1,3 linkage between the 3rd and 4th glucosyl residue.  相似文献   
22.
The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum to the untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser trapping of untransmissive particles using an attractive force caused by the diffraction and radiation force caused by reflection. The laser trapping system includes CW YAG laser, which has 1.064 μm in wave length and an optical microscope. The motions of particles were monitored by a CCD camera on the top of the microscope and recorded by PC connected to the CCD camera.  相似文献   
23.
Molecular vibrations in the solid-state, detectable in the terahertz (THz) region, are the subject of research to further develop THz technologies. To observe such vibrations in terahertz time-domain spectroscopy (THz-TDS) and low-frequency (LF) Raman spectroscopy, two supramolecular assemblies with the formula [NdIII (phen)3 (NCX)3] 0.3EtOH (X = S, 1-S; Se, 1-Se) were designed and prepared. Both compounds show several THz-TDS and LF-Raman peaks in the sub-THz range, with the lowest frequencies of 0.65 and 0.59 THz for 1-S and 1-Se, and 0.75 and 0.61 THz for 1-S and 1-Se, respectively. The peak redshift was observed due to the substitution of SCN by SeCN. Additionally, temperature-dependent TDS-THz studies showed a thermal blueshift phenomenon, as the peak position shifted to 0.68 THz for 1-S and 0.62 THz for 1-Se at 10 K. Based on ab initio calculations, sub-THz vibrations were ascribed to the swaying of the three thiocyanate/selenocyanate. Moreover, both samples exhibited near-infrared (NIR) emission from Nd (III), and very good thermometric properties in the 300–150 K range, comparable to neodymium (III) oxide-based thermometers and higher than previously reported complexes. Moreover, the temperature dependence of fluorescence and THz spectroscopy analysis showed that the reduction in anharmonic thermal vibrations leads to a significant increase in the intensity and a reduction in the width of the emission and LF absorption peaks. These studies provide the basis for developing new routes to adjust the LF vibrational absorption.  相似文献   
24.
It is well known that the morphologies of the α martensite formed from the γ phase in ferrous alloys are classified into five types of lath, butterfly, (225)A type plate,lenticular and thin-plate. Among those α martensites, onlythe thinplate martensite, which is characterized by containing a high density of transformation twins, has a potential of exhibiting a perfect shape memory (SM) effect.Recently the present authors found in Fe-Ni-Si alloys that the thin-plate martensite is formed by the introduction of fine and coherent γ-(Ni,Fe)3Si particles with a L12 ordered structure in the austenite matrix due to ausaging. In the present study, the SM properties of the ausaged Fe-Ni-Si alloys with the thin-plate martensite are investigated by a conventional bending-test. The effects of the addition of Co to the Fe-Ni-Si alloys on the martensitic transformation and the SM properties are also investigated. It is shown that while the ausaged Fe-Ni-Si ternary alloys exhibit an imperfect SM effect due to reverse transformation from stress-induced thin-plate martensite to austenite, the SM properties are improved by the addition of Co. An almost perfect SM effect is confirmed in the Fe-Ni-Si-Co alloys by heating to 1 100 ℃ after deformation at -196 ℃.  相似文献   
25.
To measure the characteristics of ultrasonic motors, such as the maximum torque, torque-speed relationship and the frictional coefficient at the contact surface, a method in which the torque is calculated from the transient responses is proposed. The rise curve that is the transitional change in the rotor speed soon after turning on the motor gives the load characteristics, while the fall curve that is the decay of the rotor speed after turning off the motor yields the frictional coefficient of the contact surface. This method requires only a short time (the transient time of the motor) to complete the measurement. The relations between the transient responses, the load characteristics and the frictional force are analyzed, and the method is applied to a hybrid transducer type rotary motor and a traveling wave type linear motor.  相似文献   
26.
Because of the significant changes in environmental policies and electric power deregulation in the last decade, a lot of photovoltaic generations (PV) have been and will be installed into the power system in Japan and the ratio of PVs to other synchronous generators will be increased. As a countermeasure against the decrease in the rotational inertia in the whole power system, a virtual synchronous generator (VSG) model control of the PV has so far been proposed. However, the system stabilization effect of the VSG in large‐scale power systems has been unclear. In this paper, a virtual step‐out blocking method of VSG for improving the transient stability is proposed. In addition, the necessity of governor control of VSG in a large‐scale power system is discussed. Finally, the rated kw and kwh capacities of the battery required for realizing the VSG‐model control are evaluated.  相似文献   
27.
Herein, the thermal and ultraviolet (UV)-irradiation solidification of indium-oxide (In-O) cluster gel, which is made from an indium acetylacetonate solution using propionic acid as a solvent, is reported. The cluster gel is an assembly of hybrid clusters, which has In-O cores coordinated with organic ligand molecules. It is confirmed that the well-defined structure of the cluster gel enables us to have a predictable solidification in the thermal treatment. Hence, we are able to understand what happens in each temperature stage from solution to solid, which can be strictly defined. It is observed that even the amount of the residual solvent in the gel is a function of temperature. The limitation of thermal pyrolysis is also clarified in the carbon-based solution. Some amounts of hybrid clusters remain even after annealing at 500 °C, leading to a carbon content that is higher than 10 at% and large Vth shift due to many defects in the fabricated thin-film transistors. As for the UV treatment, it is confirmed that the UV irradiation solidifies the gel even at room temperature (RT). Moreover, it is found that the UV reactions generate new carbon bonds, which have a higher binding energy than those in the starting gel. Although the residual organics in the gel prevent the growth of the In-O core in the case of UV irradiation at RT, the combination of thermal and UV treatments makes possible the growth of fine In-O crystals with reduced (2 at%) and stabilized carbon elements. As a result, it can be stated that a good semiconductor film is developed even at a temperature as low as 200 °C by using this combined treatment.  相似文献   
28.
This article describes a novel technique for detecting a human and his or her body direction using the histograms of oriented gradients (HOG) feature. The HOG feature is a well-known feature for judging a human, but normally it contains a background feature, which has a negative influence on the judgment. This article proposes the employment of the HOG feature based on a human model. The feature is also employed for detecting the direction of a human body. Experimental results show the effectiveness of the proposed technique compared with conventional ones.  相似文献   
29.
We have improved the conventional analytical method of the scattering data obtained with in‐situ synchrotron X‐ray scattering experiments, which is applicable to the structural characterization of the film during stretching. Four components of molecular chains in the film are divided from two‐dimensional wide‐angle X‐ray diffraction patterns. These components are the oriented crystals, the unoriented ones, the oriented amorphous chains, and the unoriented ones, respectively. This method allows to evaluate directly the degree of orientation of the amorphous chains and the amount of the oriented amorphous fraction in addition to each evaluation for the crystalline regions. This method is applied to the structural characterization of the poly(vinyl alcohol) (PVA) film during stretching in boric acid aqueous solutions, suggesting that boric acid accelerates orientation of molecular chains in the amorphous regions, and increases the oriented amorphous fraction by producing the cross‐links between the PVA chains and hindering strain‐induced crystallization. At a film break on stretching in the 3 wt% boric acid solution, the oriented amorphous fraction increases up to 70%, which is much higher compared to that in the film stretched in water, 45%. POLYM. ENG. SCI., 55:513–522, 2015. © 2014 Society of Plastics Engineers  相似文献   
30.
An experimental investigation of the tribo-electrification of glass beads fed by an ejector has been conducted by measuring both the current generated at the pipe wall and the specific-charge measured by a Faraday cage under sudden change of fluid flow in the junction between a stainless-steel branch pipe and a stainless-steel straight pipe. In measuring a current per unit mass, for Dp,50 ? 206 μm at the branch pipe section the current has a positive value as expected by the contact potential difference between glass beads and stainless-steel. On the other hand, for Dp,50 ? 105 μm at the branch and straight pipe section, the current has a negative value couldn’t be explained solely by the contact potential difference. In measuring a specific-charge by the Faraday cage, the specific-charge has a negative highest value at the ejector. The negative specific-charge decreases along the particle flow direction. Therefore, an “unusual” charge-transfer, which couldn’t be explained solely by the contact potential difference, was confirmed also by the Faraday cage. Although the charge-transfer between the beads and the inclined stainless plate with high impact speed has been examined, the sign of the current is positive for all data. It was found that the “unusual” charge-transfer in this study couldn’t be caused by the high speed impaction. An negative current in air by using a stainless steel needle detected at the ejector for Dp,50 = 51 μm while an positive current in air detected at the branch and straight pipe. The reason is suggested that the ion balance in the air does not keep between the ejector and the branch pipe due to both the adsorption of some negative ions on the pipe wall and the decrement of negative charge of particles. Therefore the “unusual” charge-transfer consists of not only the ionization caused by the self-discharge but also an adsorption of ions on the inner wall of the pipe.  相似文献   
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