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71.
The states in the surface and the bulk phases of Na ion-sensitive polymeric membranes based on a synthetic carrier were investigated using SEM, IR, 13C-NMR, and GC. The 13C-NMR study revealed that conformation change of the carrier took place when the carrier was incorporated into the membrane phase. From SEM, IR, and 13C-NMR experiments with a deteriorated membrane, the conformation change of the carrier was proposed as one of the deterioration factors other than the decrease in the diffusion coefficient of the carrier in the membrane phase.  相似文献   
72.
The segregation of daughter DNA molecules at the end stage of replication of plasmid ColE1 was examined. When circular ColE1 DNA replicates in a cell extract at a high KCl concentration (140 mM), a unique class of molecules accumulates. When the molecule is cleaved by a restriction enzyme that cuts the ColE1 DNA at a single site, an X-shaped molecule in which two linear components are held together around the origin of DNA replication is made. For a large fraction of these molecules, the 5' end of the leading strand remains at the origin and the 3' end of the strand is about 30 nucleotides upstream of the origin. The 3' end of the lagging strand is located at the terH site (17 nucleotides upstream of the origin) and the 5' end of the strand is a few hundred nucleotides upstream of the terH site. Thus the parental strands of the molecule intertwine with each other only once. When the KCl concentration is lowered to 70 mM, practically all of these molecules are converted to daughter circular monomers or to catenanes consisting of two singly interlocked circular units.  相似文献   
73.
Thyroid-stimulating hormone (TSH) beta subunit cDNA was obtained from Japanese quail (Coturnix japonica) by PCR and its nucleotide sequence was determined. The cDNA encodes a putative signal peptide and a mature protein consisting of 20 and 114 amino acids, respectively. The amino acid sequence of quail TSHbeta subunit shows homologies of 67-69% in mammalian species, 58% in amphibian and 43-49% in teleost fish. Comparison of the amino acid sequence with TSHbeta subunits of other species reveals some differences in several regions responsible for its biological functions and characteristic features of the avian TSHbeta subunit, suggesting that the functional domains have diverged cooperatively between the hormone and its receptor during evolution.  相似文献   
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75.
An internal monostandard method is proposed for the nondestructive determination of major elements in large samples by prompt γ ray neutron activation analysis. It successfully overcomes the problems characteristic of large samples, such as the absorption and scattering of incident neutrons and the absorption of emitted γ rays. In order to make this proposed method understood theoretically, an equation is presented and its validity for the analysis of large samples discussed. In principle, the proposed method gives relative contents in large solid samples, whereas it allows absolute determination for samples in solution form. As a demonstration for the analysis of a large solid sample, we analyzed an earthen vessel, and the major elements in the sample (Na, Mg, Al, Si, K, Ca, Ti, Mn, and Fe) were determined within the uncertainty of 10%, except for Mn. This method was also tested for samples in solution form, and it was found that the absolute content of a target element could be obtained by constructing a calibration curve using several known standard solutions of different concentrations. Residual radioactivity after irradiation was also examined and found to be so little that the sample could be taken outside the radiation-controlled area within a few days after the irradiation.  相似文献   
76.
Abstract— The development of multi‐primary‐color (MPC) display systems is one of the big paradigm shifts in recent display technologies and induces new potentials of display devices. The development of MPC display systems for different goals is briefly reviewed. Especially, by employing MPC systems, it is possible to reproduce the real material colors faithfully and efficiently. For signal processing, MPC systems have a big advantage in the so‐called color‐reproduction redundancy. A number of applications can be derived from this characteristic, such as improving the viewing‐angle dependency issue and power savings. On the other hand, MPC systems have a typical trade‐off versus RGB‐standardized input signals, especially for reproducing bright green. New algorithms to moderate this trade‐off on MPC systems by employing color‐reproduction redundancy are proposed. The goal of our algorithms is to maintain the compatibility with RGB‐based input signals though the initial display design so that the characteristics of MPC systems are not changed or lost. These algorithms indicate that MPC display systems are applicable not only for a specifically limited objective but also for other applications, e.g., TV broadcasting.  相似文献   
77.
In order to give a new insight to fundamental problems of quantum mechanics, relativity and mind, we propose a world model suggested from the monadology of Leibniz. The world is assumed to consist of monads which have their individuality and whose primary attribute is a space-time frame and not a position in spacetime. Each monad has freedom to change its frame. Accompanying this change, the world time is put forward, and the world state jumps off the unitary evolution. This model explains not only the measurement process of quantum mechanics but also the passing now and the origin of free will.  相似文献   
78.
Corrosion behavior of parent and weld materials of F82H and JPCA was studied in the circulating LBE loop under impinging flow. These are candidate materials for Japanese Accelerator Driven System (ADS) beam windows. Maximum temperatures were kept to 450 and 500 °C with 100 °C constant temperature difference. Main flow velocity was 0.4-0.6 m/s in every case. Oxygen concentration was controlled to 2-4 × 10−5 mass% although there was one exception. Testing time durations were 500-3000 h. Round bar type specimens were put in the circular tube of the loop. An electron beam weld in the middle of specimens was also studied. Optical microscopy, electron microscopy, X-ray element analyses and X-ray diffraction were used to investigate corrosion in these materials. Consequently corrosion depth and stability of those oxide layers were characterized based on the analyses. For a long-term behavior a linear law is recommended to predict corrosion in the ADS target design.  相似文献   
79.
80.
This paper shows the numerical investigation of the developed solar-desiccant cooling system applied in the East Asian climatic conditions with two different desiccant wheel coating materials – the Silica-Gel (SiO2) and the Titanium Dioxide (TiO2). The developed and validated numerical model of the system is currently used in the present study incorporating the two new materials in the desiccant wheel. The system was applied in temperate climate (Beijing and Tokyo), subtropical climate (Taipei and Hong Kong) and tropical climate (Manila and Singapore). The study showed that the specification of the solar-desiccant cooling system varies depending on the climatic conditions. It showed that the required flat plate collector area was getting larger from the temperate climate to the tropical climate. The storage tank requirement was getting bigger in the tropical climate compared to the subtropical and temperate climate. The volumetric flow rate of air was getting higher from temperate climate to tropical climate. In the comparison of the two materials, it was found that the Titanium Dioxide (TiO2) can support lower indoor temperature and humidity ratio than the Silica-Gel (SiO2) with the same specification of the solar thermal system and desiccant cooling system. In general, the solar-desiccant cooling system can provide the required indoor temperature and humidity ratio. However, for the hot and humid climate such as in tropical, large size of the solar thermal system is needed. In addition, higher volumetric flow of air to support the high cooling load is required. With regard to the new material, Titanium Dioxide, it is proven to be a good alternative material since it can provide lower indoor temperature and humidity ratio with higher cooling performance than the Silica-Gel.  相似文献   
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