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71.
In this paper, a model estimating the time-dependent distribution of cluster size consisting of fine particles in Newtonian molten polymer was proposed. The present model for agglomerative suspension was developed based on Usui’s thixotropy model, derived by taking the balance between shear breakup, shear coagulation and Brownian coagulation processes. The analysis was applied to the experimental results for silica/(ethylene methyl-meta acrylate copolymer) suspensions. The time variations of cluster size distributions, of viscosities and of the mean numbers of particles in a cluster were calculated and the results were compared with experimental results for the cases of shear rates from 0.2 to 10 s?1 when the solid volume fraction was set at 0.15. From the results, it was found that the present model can estimated the steady state values of the slurry viscosity and the mean particle numbers in a cluster as well as Usui’s original model. However, the model could not sufficiently express the time variation of rheological characteristics due to the over-estimation of the contribution of shear rate when the cluster size is small.  相似文献   
72.
A multilingual disaster information system (MLDI) has been developed to overcome the language barrier during times of natural disaster. MLDI is a web-based system that includes templates in nine languages so that translated texts can be made available immediately. Mobile phone e-mail with graphic text is a useful tool for delivering multilingual disaster information. The visibility of graphic text on mobile phones was measured and found to be equivalent to the built-in font. However, visibility deteriorates as the character size becomes smaller, especially, on displays with poor resolution. This article also discusses the necessity of multilingual information and measures for a safe and barrier-free society.  相似文献   
73.
Hasegawa T 《Analytical chemistry》1999,71(15):3085-3091
A novel analytical technique based on the detection of minute bands in a mixture spectrum with the use of principal-component analysis (PCA) is presented. This new aspect of PCA indicates that overlapped spectra of some components can be separated with no a priori knowledge of the components when the absorbances of the components vary greatly. This technique can be used for the detection of minute chemical species. The concept was confirmed by computer simulations. In the simulations, abstract spectra (loading vectors) were successfully obtained, and the changes of the component absorbances were also successfully followed semiquantitatively by calculating their scores. The method developed with PCA was applied to the analysis of infrared reflection-absorption (RA) spectra to study molecular interaction mechanism between alkyl-deuterated dipalmitoylphosphatidylcholine (DPPC-d(62)) monolayer and sucrose. The samples were Langmuir-Blodgett (LB) films of the DPPC-d(62) monolayer that was prepared on a sucrose solution. The LB films consisted of the following phases: air/DPPC-d(62) + sucrose/sucrose/substrate (gold). The abstract spectra corresponding to "DPPC-d(62) + sucrose" and "sucrose" phases were successfully separated by PCA, and the absorbance change of sucrose in each phase was semiquantitatively calculated from the score. The absorbance change was experimentally confirmed with quartz-crystal microbalance (QCM) experiments. In addition, minute water molecules that remained in the LB films after drying were readily detected from an abstract spectrum, and their binding site was found to be the phospholipid moiety in the head group of DPPC-d(62).  相似文献   
74.
We have performed scanning tunneling microscopy/spectroscopy (STM/STS) on single crystals of heavily Pb-doped Bi 2 Sr 2 CaCu 2 O y (Pb-Bi2212). The obtained STM images clearly demonstrated phase separation into the and phases with lamella-type and new zigzag-like microstructures. From the site-specified tunneling measurements, it was directly confirmed that the phase possesses higher T c . This suggests that the phase boundaries act as strong pinning sites especially at higher temperatures.  相似文献   
75.
Under magnetic fields perpendicular to the conductive plane in quasi-two-dimensional organic conductors: -(BEDT-TTF)2 MHg(SCN)4 (M= K, Rb, and Tl), the experimentally reported HT phase diagram has been explained partially. By the self-consistent numerical calculation including the quantum magnetic oscillation and the magnetic breakdown; in addition to the imperfectness of the SDW nesting, we try to completely understand the phase diagram.  相似文献   
76.
The authors describe a charge coupled device (CCD) sense amplifier in a video delay line which overcomes the major limitations of conventional floating diffusion amplifier (FDA) technology, such as limited output voltage and operating temperature range. These advances are implemented with a switched-capacitor integrator (SCI) using an op amp with a newly developed output stage in a CMOS-CCD process. This circuit is effected within the constraints of 5-V operation by using negative pulses to reach the low channel potential of the CCD in the pinning region in the final gate of the CCD. The chip operates with 14.3-MHz clock and 5-V power supply, and can process a 1.0-Vp-p signal voltage under 1% distortion, and under 4% gain variation from -20 to 70°C  相似文献   
77.
Gradient estimation via smoothed perturbation analysis (SPA) is considered for the multiclass single-server priority queue. Although the problem like this requires additional subpaths, generally it is shown that the estimators can be derived without any additional sample paths  相似文献   
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BACKGROUND: Single small enhancing computerized tomographic (CT) lesions (SSECTLs) are common in children with focal seizures. These are considered to represent solitary cysticercus granulomas. Controversy exists regarding their treatment. OBJECTIVE: To evaluate the efficacy of albendazole in cases of focal seizures with SSECTLs. DESIGN: Randomized, placebo-controlled, double blind trial. SETTING: Pediatric service of Nehru Hospital, PGIMER, an urban tertiary care teaching hospital. SUBJECTS: 63 children between 2 and 12 years of age with focal seizures for <3 months and SSECTLs. INTERVENTION: All children were randomly assigned to receive either albendazole (15 mg/kg/ day) or placebo for 28 days. CT scan was done at 1 and 3 months after beginning treatment. Codes opened after 6 months of inclusion in the study showed that 31 had received albendazole and 32 had received placebo. All children were followed up for at least 15 months. RESULTS: Disappearance of lesions on CT scan was noted in 41% of albendazole vs. 16.2% of placebo patients after 1 month of follow-up (P < 0.05) and 64.5% of albendazole- vs. 37.5% of placebo-treated patients after 3 months of follow-up (P < 0.05). During the first 4 weeks of therapy seizure recurrence was seen in 9.7% of albendazole vs. 3.2% of placebo-treated children (odds ratio, 3.32; 95% confidence interval, 0.33 to 33.8). After 4 weeks seizure recurrence was seen in 31.3% of placebo-treated children vs. 12.9% of albendazole-treated children (odds ratio, 3.07; 95% confidence interval, 1.18 to 11.15). CONCLUSIONS: Albendazole therapy results in significantly faster and increased resolution of solitary cysticercus lesions (SSECTLs) and appears to reduce the risk of late seizure recurrences.  相似文献   
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