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21.
Studies have been carried out on KrF excimer laser light (EX), X-ray or electron beam (EB) induced polymerization of 10,12-pentacosadiynoic acid (PDA) Langmuir-Blodgett (LB) films in relation to molecular density or molecular arrangement of the films using X-ray diffraction analysis, infrared (IR) spectroscopy and Raman spectroscopy. The molecular arrangement or density of the PDA LB films was controlled by subphase conditions when the films were built up, such as pH, temperature of a subphase or salt concentration in the subphase. Polymerization sensitivity of the PDA LB film was affected by the arrangement or molecular density. On low density (A type) films the polymerization occurred by irradiation with EX, X-ray or EB, but on high density (B type) films the polymerization occurred only when the irradiation was carried out by high energy beams such as X-ray or EB. Decomposition of polymerized films was observed further by excessive irradiation of EX or X-ray, but not on the B type films. It was revealed by X-ray diffraction analysis that in the A type film, the PDA molecules bent to a larger extent than those in the B type film and the polymerization proceeded topochemically, that is, the thickness decreased little after EB irradiation in a helium atmosphere. On the other hand, in the B type film, the thickness decreased by about 10% as a result of EB irradiation. By IR reflection-absorption (RA) and Raman measurements, it was confirmed that conjugated diacetylenic bonds disappeared and conjugated double and new conjugated triple bonds appeared after high energy beam irradiations. These results support the supposition that 1,4-polymerization, i.e. polydiacetylene type polymerization, occurs easily in the A type film and 1,2- or 3,4-polymerization, i.e. polyacetylene type polymerization, occurs in the B type film, and that the polymerized A type film was decomposed at the polydiacetylenic bond when the irradiation continued further. It was also shown that the polyacetylene type polymer was obtained only when the B type film was irradiated with the high energy beam.  相似文献   
22.
A new evacuation method for emergencies, the Follow Me method, in which each leader takes only one evacuee to an exit without gesturing or loudly directing many evacuees toward the exit, was compared, in two field experiments, with a traditional method, the Follow Directions method, in which each leader indicates the direction with a loud voice and vigorous gestures. Results showed that the Follow Me method was more effective when the leader-to-evacuee ratio was relatively small, such as 1:4, and less effective when the ratio was large, such as 1:8. Effective evacuation by the Follow Me method was shown to be caused by the drawing power of emergent small groups. Generating from around a leader, other evacuees rapidly formed a collective stream toward the exit. Small groups can be used as a lever in moving a larger collectivity in an emergency, as well as in activating a large formal organization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
The total volume change included gel and surrounded water with the swelling of five types of speherical cross-linked dextran (Sephadex) that are either nonionic (G) or possess one of four different ionic groups in the same molecular skeleton: CM: sodium carboxymethyl, SP: sodium sulphopropyl, DEAE: diethylaminoethyl chloride, and QAE: diethyl-(2-hydroxypropyl) aminoethyl chloride. All have been studied by dilatometry. The total volume decreased with the swelling of all Sephadexes. The maximum changes of total volume with the swelling in water were all negatives of CM, G, SP, (DEAE, QAE), which decrease in that order. These values did not depend on the concentration of sodium chloride and were closely related to the maximum heats of swelling. Total volume changes occurred by the dissociation of the ionic group of dextran derivatives that subtracted the total volume change due to hydration of Sephadex skeleton from the total volume change: ?21.6 ± 3.1 μL mmol?1 for CM, ?2.8 ± 8.0 μL mmol?1 for SP, +13.2 ± 4.4 μL mmol?1 for DEAE, and +15.4 ± 4.6 μL mmol?1 for QAE. These values are assumed to be reflected in the quantities of ions-water interaction of Sephadexes. © 1994 John Wiley & Sons, Inc.  相似文献   
24.
Transaction Oriented Prolog-Online Environment is a multi-user, mainframe implementation of the logic programming language Prolog, specially designed and developed for the data processing environment. This article describes the background, functionality, implementation and use of TOP-ONE, stressing that applications of knowledge-based systems technology to data processing environments will achieve full success only when existing systems and existing conventional data are incorporated within the applications.  相似文献   
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26.
Synchronous mode-locking was achieved in passively mode-locked semiconductor lasers using optical pulses with repetition rates at subharmonics of the cavity round-trip frequency. Stable and continuous mode-locked pulses at 8.5 GHz were generated when the repetition rate of the control optical pulses was 4.25 GHz (2nd subharmonic). The timing jitter of the mode-locked pulses was reduced to 1 ps. The relationship between repetition rates of the control pulses and the realization of stable and continuous mode-locking was examined.  相似文献   
27.
One hundred and ninety-eight adolescents and their mothers (N = 189) and fathers (N = 136) participated in a 4-year longitudinal study. Adolescent problem behaviour was assessed by the Youth Self-Report (YSR) and the Child Behavior Checklist (CBCL). In addition, parental stress and marital adjustment were determined. Results showed that mothers and fathers showed high agreement, especially about their daughters, whereas parents and adolescents showed little agreement. Agreement was higher for internalising than for externalising behaviours. In general, adolescents reported more symptomatology than their parents did. However, mothers' ratings of their children's behaviours were significantly correlated with adolescents' self-ratings, but fathers' ratings were not. Statistical tests of correlations showed that mothers experiencing stress caused by marital problems perceived more problem behaviours in their children. Fathers' perceptions were relatively unaffected by personal adjustment. However, poor marital adjustment perceived by both parents showed a significant negative relation to adolescent externalising problem behaviour.  相似文献   
28.
A flow cytometric virus binding assay that directly visualizes the binding of infectious bursal disease virus (IBDV) to its target cells was established. The chicken B lymphoblastoid cell line, LSCC-BK3, which is permissive for IBDV infection, bound high levels of the virus. Another B lymphoblastoid cell line, LSCC-1104-B1, bound low levels of the virus, although it was nonpermissive. No virus binding was detected in nonpermissive T lymphoblastoid cell lines. In the binding assay to heterogeneous cell populations of chicken lymphocytes, IBDV (a highly virulent OKYM strain) bound to 94% cells in the lymphocytes prepared from the bursa of Fabricius, 37% cells in those prepared from the spleen, 3% cells in those prepared from the thymus, and 21% cells in those prepared from the blood. Most of the cells, which bound the virus, were surface immunoglobulin M (SIgM)-positive, but a small number of them were SIgM-negative. Additionally, the binding of IBDV to the LSCC-BK3 cells was affected by treatment of the cells with proteases and N-glycosylation inhibitors. These findings may indicate that the IBDV host range is mainly controlled by the presence of a virus receptor composed of N-glycosylated protein associated with the subtle differentiation stage of B-lymphocytes represented mostly by SIgM-bearing cells.  相似文献   
29.
Inflammatory pseudotumor of the liver is a rare lesion characterized by proliferating fibrovascular tissue admixed with inflammatory cells. A 50-yr-old Japanese man was hospitalized because of upper abdominal pain and high fever. Computed tomography revealed a poorly demarcated, low density mass in the left lobe of the liver, and abnormal laboratory findings included WBC 9340/mm3, CRP 10.5 mg/dl, and marked elevation of CA19-9 to 1167.9 U/ml. Endoscopic retrograde cholangiography showed irregularity of the intrahepatic bile duct of the left lateral segment, and the lateral segmental branches of the portal vein were not visualized on the venous phase of abdominal angiography. Ultrasound-guided liver biopsy was performed, but malignant disease, including intrahepatic cholangiocarcinoma, could not be completely ruled out. The patient underwent left hepatic lobectomy with lymph node dissection. Histopathological examination yielded a definitive diagnosis of inflammatory pseudotumor. The lesion was immunohistochemically stained for CA19-9 by the ABC method, and the biliary epithelium in severely inflamed portal canals was found to be positive. The markedly elevated preoperative level of CA 19-9 decreased to almost within the normal range and the patient remains well 2 yr 9 months after surgery, without any complications.  相似文献   
30.
Amorphous specimens of Fe100–x B x were prepared in the range 10 × 35 at % B by a single-roller method. The crystallization process and the boron concentration dependence of the Curie temperature were examined by differential scanning calorimetry, X-ray diffraction, Mössbauer spectroscopy and magnetic measurements. Two-step crystallization was observed in specimens with× < 17: amorphous amorphous + boron-supersaturated b c c phase (-Fe(B)) t-Fe3B +-Fe. A single-Fe(B) phase was not observed. The transition temperature from t-Fe3B to stable (-Fe + t-Fe2B) sensitively depends on the boron content in the alloys. The crystallization temperature (T x) of the amorphous alloys was almost unchanged for 17 × 31, but increased remarkably at high boron concentrations of× 33, where the decomposition products consisted of t-Fe2B and o-FeB. The Curie temperature (T c) of the amorphous phase was as low as 480 K at× = 10, increased with increasing boron content up to 820 K and then decreased in the high boron concentration alloys of× > 28. A single-Fe(B) phase was not detected in the as-quenched specimens of× = 8 and 10. The phase coexisted with the o-Fe3B and amorphous phases. The lattice parameter of the phase was 0.28610 nm which was smaller than that of pure iron by 2/1000, indicating the substitutional occupation of boron atoms in the b c c lattice.  相似文献   
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