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1.
Electromechanical transducers for sensing and actuating disturbances or vibrations have been used in many fields of applications. There have been transducers of different configuration developed for the unidirectional transduction. This paper demonstrates a single element transducer for tri-axial components made of a piezoelectric cylindrical shell. The separation of the tri-axial transductions is achieved by devising a proper electrode arrangement. The structure and the fundamental idea are first presented, and then the numerical analysis by means of the finite element modeling follows, and their characteristics and behaviors are then experimentally verified.  相似文献   
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3.
Pd(dibenzylideneacetone)2, when activated in situ with 1 equiv of [CPh3][B(C6F5)4] in the presence of 1 equiv of P(C6H11)3, efficiently catalyzed the addition polymerization and copolymerization of norbornene and its derivatives. Homopolymerization of 5-vinyl-2-norbornene took place regio-selectively with the endo-cyclic double bond to give high-molecular weight polymers, while the exocyclic double bond remained intact so that the resulting polymer had pendent vinyl groups along the polymer chain. In the polymerization of a mixture of the endo-/exo- isomers of 2-methoxycarbonyl-5-norbornene, the endo-isomer was consumed prior to consumption of the exo-isomer, contrary to the well-known tendency in Pd(II)-based catalyst systems. Another notable feature of the present catalytic system was the strong dependency of the molecular weight on the reaction temperature, which was studied in detail for the copolymerization of 2-methoxycarbonyl-5-norbornene with norbornene: we could control the molecular weight without the use of a chain transfer agent. The extracted oligomeric fraction of poly(norbornene) showed the presence of a terminal CC double bond as well as a C6F5 unit that was bound to the first norbornane unit in the polymer chain.  相似文献   
4.
To simulate the corrosion of galvanized steel in marine zone, β-FeOOH was prepared by aging the FeCl3 solutions containing ZnCl2 and zinc rusts such as ZnO and zinc hydroxychloride (Zn5(OH)8Cl2·H2O:ZHC). Adding ZnCl2, ZnO, and ZHC inhibited the crystallization and particle growth of β-FeOOH and the inhibitory effect was in order of ZHC ≈ ZnO > ZnCl2. The adsorption of H2O and CO2 was suppressed by adding ZnCl2, ZnO, and ZHC. These results imply that the rust formed on galvanized steel in marine environment is more compact, amorphous, and hydrophobic in nature which may lead to improve the corrosion resistance.  相似文献   
5.
Lauryl sulfate and lauryl ether sulfate obtained by the sulfation of lauryl alcohol and lauryl alcohol ethoxylate are representative of anionic surfactants and are used as a formable detergent or an emulsifier. For the sulfation of lauryl alcohol and lauryl alcohol ethoxylate, SO3 gas, it was found that the quality of products was significantly influenced by the reaction conditions. In order to obtain good quality products we developed a new technology by using a new type of reactor called a “climbing film reactor,” in which SO3 gas and liquid raw material flow ascendingly.  相似文献   
6.
ALG-2, a 22-kDa penta-EF-hand protein, is involved in cell death, signal transduction, membrane trafficking, etc., by interacting with various proteins in mammalian cells in a Ca2+-dependent manner. Most known ALG-2-interacting proteins contain proline-rich regions in which either PPYPXnYP (type 1 motif) or PXPGF (type 2 motif) is commonly found. Previous X-ray crystal structural analysis of the complex between ALG-2 and an ALIX peptide revealed that the peptide binds to the two hydrophobic pockets. In the present study, we resolved the crystal structure of the complex between ALG-2 and a peptide of Sec31A (outer shell component of coat complex II, COPII; containing the type 2 motif) and found that the peptide binds to the third hydrophobic pocket (Pocket 3). While amino acid substitution of Phe85, a Pocket 3 residue, with Ala abrogated the interaction with Sec31A, it did not affect the interaction with ALIX. On the other hand, amino acid substitution of Tyr180, a Pocket 1 residue, with Ala caused loss of binding to ALIX, but maintained binding to Sec31A. We conclude that ALG-2 recognizes two types of motifs at different hydrophobic surfaces. Furthermore, based on the results of serial mutational analysis of the ALG-2-binding sites in Sec31A, the type 2 motif was newly defined.  相似文献   
7.
Research and development of firefighters’ protective clothing relies on a large number of fire disaster experiments in order to assess the thermal performance. It would be substantially advantageous to substitute a virtual numerical experiment for a real one in terms of time, cost and safety. The present article reports the development of an integrated numerical simulator that makes possible the estimation of burn injuries originating from fire disasters. In the simulator, a general-purpose computational fluid dynamics program computes the fluid flow and heat transfer in an in situ fire event, while a one-dimensional program calculates the radiative–conductive heat transfer through the clothing and human skin. A data interface combines the two simulations by loose coupling so as to give the real-time burn injury progress output. The predicted surface heat fluxes and burn degrees agree with experimental measurements reasonably well. Possible numerical error sources are discussed that call for potential improvements in the future.  相似文献   
8.
By screening with monoclonal antibodies (mAbs) raised against growth cone membrane fraction from fetal porcine brains, we have identified a 230 kDa antigen, termed p230. Western blot analysis of extracts from various tissues demonstrated that p230 is specifically expressed in brains, in which its expression is temporally restricted; it was especially prominent in the embryonic and the early postnatal stage, and decreased to subdetectable levels in the adult brain. Further characterization of p230 revealed that it is a peripherally-membrane associated, cell surface protein produced by astrocytes. Neurite outgrowth of E18 rat cerebral cortex neurons cultured on a monolayer of astrocytes was significantly reduced in the presence of anti-p230 polyclonal antibody. Partial amino acid sequences of p230 purified from fetal porcine brains were highly homologous to an extracellular matrix protein, tenascin-C. These lines of evidence suggest that p230, a tenascin-C-like molecule present in fetal porcine brains, plays important roles during early brain development, particularly in growth cone guidance.  相似文献   
9.
Seed storage globulins of the 7S and 11S type are synthesized in the seeds of angiosperms and gymnosperms. We have isolated and characterized a vicilin-like gene expressed in the cycad Zamia furfuraceae. Sequence comparisons reveal clear similarities to a sucrose-binding protein isolated from soybean. We suggest the existence of a superfamily of related genes including both vicilin-like and legumin-like seed globulin genes as well as genes coding for spherulins, germins and sucrose-binding-proteins.  相似文献   
10.
The organization and nucleotide sequence of the capsular gene cluster involved in the biosynthesis of the type 33F capsular polysaccharide of Streptococcus pneumoniae have been determined. The complete type 33F operon (cap33f) is composed of 14 potential open reading frames where the last ten genes are group-specific. Putative functions have been assigned to several gene products by sequence comparison with the proteins included in the databases. A functional promoter located immediately upstream from the first gene of the cap33f gene cluster has been demonstrated. A 20 kb DNA fragment containing the cap33f genes and the operon promoter was sufficient to transform a S. pneumoniae type 3 unencapsulated mutant to the type 33F capsule.  相似文献   
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