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11.
In a TEA CO2 laser a two-stage spark gap was used to control the predischarge, which produced the ultraviolet-preionization, and to generate a trigger pulse for the Marx bank, which excited the main discharge. The time-sequence of the predischarge and the trigger pulse could be reversed so that the main discharge could commence before the preionization process. This set-up has enabled temporal synchronization on the laser performance, or basically the time delay between the pre- and the main discharges, to be investigated from about − 150 ns to 600 ns.  相似文献   
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The thermal characteristics of polyaniline (PANI), poly(o-aminobenzoic acid) (POABAC) and poly(o-aminobenzyl alcohol) (POABOL) are determined and compared by thermogravimetry (TG) and differential scanning calorimetry (DSC). The higher thermal stability of POABOL is attributed to heat-induced condensation between the polymer chains. The DSC results suggest both intra- and inter-molecular interaction in the form of hydrogen bonding due to the substituent group in POABAC and POABOL. These interactions, however, occur mainly in the doped from and is greatly reduced when the dopant is expelled from the system at higher temperatures.
Zusammenfassung Es wurden die thermischen Eigenschaften von Polyanilin (PANI), Poly(o-aminobenzoylsäure) (POABAC) und Poly(o-aminobenzylalkohol) (POABOL) ermittelt und mittels TG und DSC miteinander verglichen. Die höhere Thermostabilität von POABOL wird der wärmeinduzierten Kondensationsreaktion zwischen den Polymerketten zugeschrieben. Die DSC-Resultate weisen auf sowohl intra- als auch intermolekulare Wechselwirkungen in Form von Wasserstoffbrückenbindungen infolge der Substituenten in POABAC und POABOL hin. Diese Wechselwirkungen treten hauptsächlich in der dotierten Form auf und werden in großem Maße reduziert, wenn die Dotierungsmittel bei höheren Temperaturen ausgetrieben werden.
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章新友  L.J. Li  黄永畅 《物理学报》2014,63(19):190301-190301
本文获得了有各种相互作用的一般n阶特征量泛函,其耦合系数反映了不同特征量泛函之间的耦合强度.依据定量因果原理,导出了一般n阶特征量泛函的变分原理,获得了一般n阶特征量泛函的Euler-Lagrange方程,它的不同系数可拟合不同的物理现实,如从线性到任意n阶非线性物理系统,使复杂难解的任意n阶非线性物理系统变得具体可解.并获得了该对称变换下不变的m个的守恒量,以及它们之间的关系和统一描述.依据定量因果原理导出了相对性原理,证明了绝对加速参考系、牵连参考系和相对参考系的力都有来自加速度和质量变化的贡献.利用定量因果原理自然导出了广义牛顿第一定律和广义牛顿第二定律,而且还导出了一个新定律,即广义牛顿第三定律,亦即平移不变性系统合力为零定理.进而将研究结论应用于对银河系的修正引力势、分子势、夸克禁闭势等,且其结果与物理实验一致.  相似文献   
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For centuries, the edible nests of Collocalia spp. ("Bird's Nests") have been used as a Chinese delicacy that had been claimed to be an effective health-giving tonic. However, clinical studies indicated that in Singapore, Bird's Nest is the most common cause of food-induced anaphylaxis in children, which could lead to potentially life-threatening allergenic reactions. The purpose of this study was to characterize the major allergens in Bird's Nest by using the combined technologies of two-dimensional gel electrophoresis (2-DE), immunochemistry, N-terminal protein sequencing, and mass spectrometry. Results from the immunostaining of the Western blots of the Bird's Nest 2-DE separated proteins with the sera from allergic patients indicated the presence of a major allergen of 66 kDa. Initial searches of the matrix assisted laser desorption/ionization--time of flight--mass spectrometry (MALDI-TOF-MS) tryptic peptide masses of the allergen in the SWISS-PROT and NCBI nonredundant databases revealed that this protein was novel. Based on the partial protein sequence information obtained from N-terminal microsequencing and nanoelectrospray-tandem MS, the 66 kDa immunoreactive allergen was found to be homologous to ovoinhibitor, a Kazal-type serine protease inhibitor, which is one of the dominant allergens found in chicken egg white.  相似文献   
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K Ou  T K Seow  R C Liang  S E Ong  M C Chung 《Electrophoresis》2001,22(13):2804-2811
Recently, we reported the proteome analysis of a human hepatocellular carcinoma cell line, HCC-M (Electrophoresis 2000, 21, 1787-1813), using two-dimensional gel electrophoresis (2-DE) and matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). From a total of 408 unique spots excised from the 2-DE gel, 301 spots yielded good MALDI spectra. Out of these, 272 spots had matches returned from the database search leading to the identification of these proteins. Here, we report the results on the identification of the remaining 29 spots using nanoelectrospray ionization-tandem mass spectrometry (nESI-MS/MS). First, "peptide tag sequencing" was performed to obtain partial amino acid sequences of the peptides to search the SWISS-PROTand NCBI nonredundant protein databases. Spots that were still not able to find any matches from the databases were subjected to de novo peptide sequencing. The tryptic peptide sequences were used to search for homologues in the protein and nucleotide databases with the NCBI Basic Local Alignment Search Tool (BLAST), which was essential for the characterization of novel or post-translationally modified proteins. Using this approach, all the 29 spots were unambiguously identified. Among them, phosphotyrosyl phosphatase activator (PTPA), RNA-binding protein regulatory subunit, replication protein A 32 kDa subunit (RP-A) and N-acetylneuraminic acid phosphate synthase were reported to be cancer-related proteins.  相似文献   
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The performance of typical three sided noise enclosures was predicted using diffraction theory. Both unlined and lined enclosures were considered. The agreement with measured results was reasonably good and thus the technique developed is of practical value.  相似文献   
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