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991.
The vinylidene structures in polypropylenes produced by ethylenebis(indenyl)zirconiumdichloride (En(Ind)2ZrCl2), 1, and isopropyl(cyclopentadienyl)(fluorenyl)zirconiumdichloride (iPr(Cp)(Flu)ZrCl2), 2, were analyzed by 1H NMR. The vinylidene group adjacent to the chain end was clearly distinguished from other internal vinylidene structures for the first time using 1,2-dichlorobenzene as solvent. The polypropylene produced by 2 had much internal vinylidene groups compared with one by 1.  相似文献   
992.
The authors have introduced an automaton on a two-dimensional tape, which decides acceptance or rejection of an input tape by scanning the tape from various sides by three-way (deterministic and nondeterministic) finite automata, and have investigated the accepting powers. This paper continues the investigation of this type of automata, which consists of four three-way two-dimensional alternating finite automata (tr2-afa’s). We first investigate a relationship between the accepting powers of ∨-type automata (obtained by combining tr2-afa’s in ‘or’ fashion) and ∧-type automata (obtained by combining tr2-afa’s in ‘and’ fashion), and show that they are incomparable. Then, we investigate a hierarchy of the accepting powers based on the number of tr2-afa’s combined. Finally, we briefly describe a relationship between the accepting powers of automata obtained by combining three-way two-dimensional nondeterministic and alternating finite automata.  相似文献   
993.
Urocanic acid (UCA) is known to be synthesized as the trans isomer (trans-UCA) in the skin, and trans-UCA is transformed by UV light to the cis isomer (cis-UCA), which may be involved in photoimmunosuppression. An electrochemical method has been developed for the measurement of the concentration and isomer ratio of UCA. A heme peptide-modified electrode (HP electrode) reduces hydrogen peroxide at +150 mV vs Ag/AgCl, and the reduction current is inhibited by UCA. Since cis-UCA is a stronger inhibitor than trans-UCA, irradiation of a sample solution with UV light increases the percent inhibition. The concentration and isomer ratio of UCA in the sample solution can be estimated from the values of percent inhibition before and after the UV irradiation.  相似文献   
994.
We propose a fast surface-profiling algorithm based on white-light interferometry by use of sampling theory. We first provide a generalized sampling theorem that reconstructs the squared-envelope function of the white-light interferogram from sampled values of the interferogram and then propose the new algorithm based on the theorem. The algorithm extends the sampling interval to 1.425 microm when an optical filter with a center wavelength of 600 nm and a bandwidth of 60 nm is used. The sampling interval is 6-14 times wider than those used in conventional systems. The algorithm has been installed in a commercial system that achieved the world's fastest scanning speed of 80 microm/s. The height resolution of the system is of the order of 10 nm for a measurement range of greater than 100 microm.  相似文献   
995.
The generation of white-light continuum by femtosecond laser pulses in transparent condensed media is investigated comprehensively with 262-, 393-, and 785-nm pump wavelengths. We find that the ratio of the medium's bandgap energy to the photon energy of the incident wavelength determines the amount of anti-Stokes broadening, independently of the pump wavelength and the medium's bandgap. It is also shown that, although the amount of anti-Stokes broadening is greater for the longer pump wavelength, the shorter pump wavelength is more advantageous for generating shorter-wavelength continua in the UV region. In addition, a self-induced change in polarization of the white-light continuum that is generated is observed in an isotropic material with a cubic crystal structure, such as CaF2 and LiF. After the investigation of polarization, the frequency chirp of the continuum is characterized by the Kerr-gate method with 70-fs temporal and 10-nm wavelength resolution.  相似文献   
996.
Zhan G  Oka K  Ishigaki T  Baba N 《Applied optics》2002,41(4):734-738
A Fourier-transform imaging spectrometer, believed to be novel, based on the Savart polariscope is presented. There is no slit in this instrument, which means that it has a high throughput. The principle and the system configuration are described. Several preliminary experimental results are shown.  相似文献   
997.
Here we describe an algorithm for identifying peptides/ proteins of known sequence and unknown peptides from partial spectra generated by an in-source decay (ISD) technique coupled with matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry. The identification of protein fragments is processed with a software program called CMATCH, which generates candidate subsequences for both known peptides/proteins and unknown peptides for the major product ions in the spectral range m/z 400-5000 and then matches these to known protein sequences contained in a reference database for the known peptides/proteins. CMATCH, which is compiled for MSDOS or WINDOWS95/NT, has two main advantages: first, the candidate subsequences are generated automatically without the need for supplementary information concerning the distribution of either N-terminal or C-terminal ions in the spectra for both known peptides/proteins and unknown peptides; second, the highest coordinated homologous sequences are picked up automatically from the reference database as the best matches with known peptides/proteins. Examples from the ISD spectra of several test proteins demonstrate the efficacy of this protein identification software.  相似文献   
998.
To preserve archive films of which the base material is composed of cellulose acetate, we carried out screening tests on various reagents. We selected sodium carbonate and sodium polyacrylate as an acetic acid gas removing agent and a dehumidification agent, respectively. The performance of sodium carbonate per unit mass in the removal of acetic acid gas was superior to those of commercial products. The presence of sodium carbonate suppressed the increase in concentration of acetic acid gas for several months in film preservation containers. The neutralization of sodium carbonate with acetic acid gas was evaluated quantitatively. Sodium polyacrylate controlled relative humidity at around 40%RH in film preservation containers, and it was effective for film preservation. The dehumidifying performance of sodium polyacrylate compared favourably with those of commercial products. Thus, the materials tested in this study are found to be useful to avoid vinegar syndrome in cellulose acetate-based films.  相似文献   
999.
The performance of a new method using pulsed streamer corona for the removal of SO2 from humid air has been evaluated. The pulsed streamer corona produces energetic free electrons that excite, dissociate, and ionize gas molecules, forming radicals that enhance the gas-phase chemical reactions that convert SO2 to acid mist and/or particulate aerosols. The aerosols are then collected by conventional means, i.e., by electrostatic precipitator or bag filter. The SO2 removal efficiency was compared with that of the electron-beam and dc corona flue-gas treatment processes. The comparison demonstrates the advantage of the novel method.  相似文献   
1000.
This paper proposes deep and fundamental structures of communication among persons in a “coexistential” setting. The basic framework for this formalization of communication structures is Leibnizian notions of space and time together with the notion of the Existential Graph by C. S. Peirce and that of the Petri net, more precisely, the occurrence net. The fundamental structures of coexistential communication are then formalized as co-creation of Leibnizian space and time in such a manner that they are used to link the communicated messages, thus establishing the “coexistential atmosphere and field” (“Ba” in Japanese) among the individuals. This framework is then applied to the analysis of theater play communication. Finally, the framework of information edaphology is also introduced to discuss the growth processes of individuals and communities through coexistential communication.  相似文献   
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