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101.
Interaction of titanium chloride with a cellulose surface and the decurrent modifications introduced on its morphology were studied by scanning, electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The chemical analysis of the surface was carried by X-ray photoelectron spectroscopy (XPS) and changes in the crystallinity upon chemical treatment was determinded by the X-ray diffraction (XRD) technique. Interaction of titanium with cellulose occurs only at the surface and a decrease of its crystallinity was observed with the amount of metal oxide incorporated into the solid matrix. © 1995 John Wiley & Sons, Inc.  相似文献   
102.
In order to explain the higher calcium sensitivity of αs2-casein than other casein constituients, properties of αs2-casein and dephosphorylated αs2-casein were examined and compared with those of αs1-casein. αs2-Casein was more sensitive to calcium than αs1-casein. Aggregates of calcium αs1- and αs2-caseinates were both thoroughly solubilized by 4 M urea. Gel filtration of αs1-casein and of αs2-casein in 4 M urea showed the same elution pattern in the presence and absence of 10 mM calcium chloride. Dephosphorylated αs2-casein was insoluble at neutral pH although dephosphorylated αs1-casein was soluble. Dephosphorylated αs2-casein was solubilized by 4 M urea and alkalization to pH 11. The net proton charge, calculated from the primary structure, of dephosphorylated αs2-casein was very low at pH 7.0, although dephosphorylated αs1-casein has a considerable number of negative net charges. The calculated isoionic point of dephosphorylated αs2-casein, which contains one phosphate group, was 6.98. Ester phosphate groups of αs2-casein play an important role in its solubilization at neutral pH and neutralization of ionized phosphate groups by calcium ion increases hydrophobic interaction, which leads to precipitation.  相似文献   
103.
In attempt to develop a new chemotherapeutic regimen including carboplatin (CBDCA), epirubicin (EPI), and VP-16 in extensive small cell lung cancer, with a higher dose intensity compared with previous experience of our group, we determined the maximum tolerated dose (MTD) of VP-16 when administered in association with CBDCA (300 mg/ m2, i.v., day 1) and EPI (75 mg/m2, i.v., day 1), recycling chemotherapy every 3 weeks, with the support of granulocyte-colony-stimulating factor (G-CSF). A total of 15 patients received three dose levels of VP-16 (mg/m2, i.v., daily on days 1-3): 100 (three patients), 120 (six), and 140 (six). G-CSF was administered subcutaneously at the dose of 5 micrograms/kg/day on days 6-15 of each chemotherapy course. The MTD was established at 140 mg/m2 and myelotoxicity, grade 4 neutropenia with death for sepsis in one case and grade 3 thrombocytopenia in three cases, was dose limiting. The recommended dose of VP-16 for a phase II study is 140 mg/m2.  相似文献   
104.
The dc brushless motor, permanent magnet-type synchronous motor (PM motor), has been used widely in industrial robots, the machine tools for factory, and factory automations. Therefore, it is more desirable to improve the performance of the PM motor variable speed control system. Although only the torque component current is adjusted as the control method for the PM motor, so-called Vector Control, it is expected that the developed characteristics will be added to the PM motor. In this paper, new driving methods for the PM motor and a new design method for the variable speed control system are presented. The new motor driving methods which bring to the PM motor a new driving performance, e.g., a quick transient response or high-efficiency motor driving, can be implemented by controlling not only the torque component current, but also the magnetizing component current. A developed optimal control theory, i.e., the error system technique, is employed for designing the control system. The control law is endowed with a steady robustness against the variation of the system parameters and the ability of compensating the delay time due to the control processing. The effectiveness of the proposed method is confirmed by simulations and experiments.  相似文献   
105.
We fabricated new 2.78‐in 1058‐ppi organic light‐emitting diode (OLED) displays. The displays used OLED devices with a tandem structure and a single structure and a field effect transistor (FET) using c‐axis aligned crystalline In–Ga–Zn–O (CAAC‐IGZO) for an active layer and employing the 1.5‐µm rule over a glass substrate. Even in the displays with such high resolution exceeding 1000 ppi, crosstalk that was observed in the lower luminance region was suppressed. The displays achieved high color reproducibility and reduced viewing angle dependence.  相似文献   
106.
An indium oxide‐based precursor solution has been developed by spin coating method. In order to apply this material to mass production, material, process, and equipment optimizations for slot die coating have been implemented. Slot die coating is a cost‐effective and scalable process and already applied to photoresist materials in the display industry. The indium oxide‐based precursor solution has been coated on bare glasses and thin‐film transistor substrates by a mass production‐type slot die coater. Mobility of over 10 cm2/Vs is achieved for the first time for a large area at an annealing temperature of 350 °C. The homogeneity of the film will be presented.  相似文献   
107.
Recently, the optimization-by-inference approach has been proposed as a new means for solving high-dimensional optimization problems quickly. Approximate Inference COntrol (AICO) is one of the most successful and promising methods that implement the optimization-by-inference approach. AICO is able to solve stochastic optimal control problems and has already been successfully used in many applications. However, it is known that the iterative inference of AICO sometimes fails to converge to the optimal solution. To make the optimization more robust, in this paper, we propose to take model uncertainty into account. In AICO, the cost function to be minimized is accurate around a particular state of a given stochastic system, but the accuracy is uncertain in regions far from that state. Because using such an uncertain function is harmful to the convergence, we modify AICO, so that it does not use the function in uncertain regions. Our method is easy to implement and does not add much computational time to the original AICO. Experiments using two different scenarios show that our method substantially improves AICO in terms of the rate at which the algorithm produces convergent results.  相似文献   
108.
Copoly(vinyl alcohol–styrenesulfonic acid) resin was prepared by a two-step polymerization, consisting of a suspension polymerization of styrene containing divinylbenzene using tetraethylthiuram disulfide as an initiator and a subsequent block copolymerization of vinyl acetate to the crosslinked polystyrene obtained, followed by sulfonation and saponification. Some reaction conditions in the polymerization of styrene were investigated to obtain copolymer containing more vinyl alcohol units. The catalytic activity of the copolymer on the hydrolysis of dextrin was investigated and found to be increased with increasing amount of vinyl alcohol units and with a lowering degree of crosslinking of the copolymer. The maximum acceleration of rate obtained in the presence of the copolymer was about six times that in the presence of Amberlite 120B. Catalytic activity of the copolymer on hydrolysis of sucrose and methyl acetate were also investigated and found to be comparable each other and lower than that for dextrin. The difference between the activities for dextrin and for sucrose and methyl acetate increased with an increasing amount of vinyl alcohol units in the copolymer.  相似文献   
109.
Hydrolysis of cellulose fiber in the presence of 12-tungstosilicic acid was investigated, and the acid was found to show a higher catalytic activity than did hydrochloric acid at the same concentration of acid, although the ratio of the activities of 12-tungstosilicic acid to hydrochloric acid depended on the concentration. The influence of the ionic strength on the reaction rates was examined, and it was believed that the difference in the ionic strength between 12-tungstosilicic acid and hydrochloric acid at the same concentration of acid was one of reasons for the higher catalytic activity of 12-tungstosilicic acid. From the examinations of change in degree of polymerization of the cellulose fiber with the hydrolysis and adsorption behavior of 12-tungstosilicic acid by the cellulose, fiber, it was found that 12-tungstosilicic acid, in spite of its bulky structure, easily penetrated into the amorphous region of the cellulose fiber, as does hydrochloric acid, and catalyzed the hydrolysis of glucoside bond there.  相似文献   
110.
The decomposition of the peroxide group on fibrous carboxymethyl cellulose (CMC) and its ability to initiate graft copolymerization were investigated. The peroxide on CMC liberated hydrogen peroxide when the sample was heated in an aqueous medium. The decomposition of the peroxide was markedly increased by the use of ferrous salt and the irradiation with light of λ > 300 nm. The grafting of methyl methacrylate on CMC peroxide was initiated by heating or irradiating with light, where the rate of grafting and the reciprocal of the average molecular weight of grafts in general were proportional to the square root of the peroxide content of the sample. The peroxide content of the sample was related closely to the number of grafts in initiation. The number was estimated as 17 times for thermal initiation and 6 times for photoinitiation at the maximum values. The CMC peroxide showed a marked activity toward photografting of acrylamide, acrylic acid, acrylonitrile, and vinyl acetate on the substrate.  相似文献   
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