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11.
The breakup of non-Newtonian emulsion jets into drops was experimentally studied by ejecting both O/W and W/O emulsions vertically downward into stagnant air through nozzles. Breakup lengths of non-Newtonian emulsion jets were found to be almost equivalent to those of Newtonian jets. Experimental breakup data establish that the static surface tension of the oil phase can be used as the surface tension of W/O emulsion jets, whereas the dynamic surface tension of aqueous surfactant solutions is used as that of O/W emulsion jets. Diameters of drops formed from non-Newtonian emulsion jets are in good agreement with the prediction from the stability theory previously developed by the authors. When the rheological index in a power law model is appreciably smaller than unity and the Ohnesorge number is significantly large, however, drop sizes are larger than the prediction because of the profile relaxation in jets. The critical velocity of emulsion jets, either O/W or W/O emulsion, is significantly lower than that of homogeneous Newtonian jets. 相似文献
12.
Individual action and synergistic effect in the combination of 6-anilino-1,3,5-triazine-2,4-dithiol (AF), zinc stearate, and barium stearate on the color stabilization of PVC were investigated. In this system, AF selectively reacts with allylic chlorine atoms in PVC. Consequently, unstable allylic chlorine units were converted to thermally stable allylic structures, thus retarding the development of polyene sequences. Zinc stearate accelerated the reaction of AF with allylic chlorine atoms in PVC, forming the zinc salts of AF (AFZnSt, St?C1–H35COO? ) by reacting with AF. Barium stearate reacted with ZnCl2 which is formed in the above reaction to give St2Zn and BaCl2. Consequently, barium stearate led to the selective reaction of AF with allylic chlorine atoms in PVC and the remarkable retarding effect of discoloration of PVC. 相似文献
13.
Tsugio Sato Kenji Dosaka Toshiaki Yoshioka Akitsugu Okuwaki Kazuo Torii Yoshiro Onodera 《Journal of the American Ceramic Society》1992,75(3):552-556
Amorphous CeO2 –ZrO2 gels were prepared by coprecipitation in ammonia solutions. The onset of crystallization of the gels, from calcining in air, was 420°C, while 200° to 250°C in the presence of water and organic solvents such as methanol and ethanol. The sintering behaviors of CeO2 –ZrO2 powders were sensitive to the crystallizing conditions, since hard agglomerates formed when the precipitated gels were crystallized by normal calcination in air, whereas soft agglomerates formed when they were crystallized in water or organic solvents. CeO2 –ZrO2 powders crystallized in methanol and water at 250°C were sintered to full theoretical density at 1150° and 1400°C, respectively, whereas that crystallized by calcination in air at 450°C was sintered to only 95.2% of theoretical density, even at 1500°C. 相似文献
14.
Synthesis of rodlike polysiloxane containing polyol moieties derived from glucose with regularly controlled higher-ordered structure 总被引:1,自引:0,他引:1
A rodlike polysiloxane (3) containing polyol moieties derived from the sugar has been synthesized by reaction of an amine-functionalized rodlike polysiloxane (1) with gluconolactone (2) in the presence of triethylamine in DMF. Formation of 3 was estimated by the IR and 1H NMR measurements. The functionality of 2 to the amino groups in 1 was ca. 75%, based on the 1H NMR spectrum of the product. The XRD profile of 3 showed three peaks for a typical hexagonal phase, and the d-value of (100) peak of 3 was larger than that of 1, indicating the regularly controlled higher-ordered structure of 3. 相似文献
15.
A heat-induced O/W emulsion gel that undergoes a phase transition from sol to gel on heating was formed from the addition of aqueous HCl to a toluene solution of a long-chain amidoamine derivative (C18AA). The heat induced O/W emulsions are highly sensitive to temperature, and the sol-gel transition temperature could be simply controlled by adjusting the C18AA concentration. Interestingly, the sol-gel transition of the O/W emulsions was also very sensitive to pH. Thus, we have successfully prepared a novel double-stimuli responsive gel based on O/W emulsions consisting of C18AA and HCl. 相似文献
16.
The sorption behavior of water vapor and CO2 gas in photocrosslinked poly(vinyl cinnamate) (PVCA) film was examined at 30°C under atmospheric pressure. Both the water sorption isotherm and the CO2 sorption isotherm obtained with quartz crystal microbalance (QCM) method obeyed the simple Langmuir's equation. Water vapor/CO2 mixed‐gas sorption isotherms were also obtained. Total amount of sorbed mixed gases was clearly influenced by the partial pressure of water vapor (pw) and CO2 gas (pc) in the atmosphere. A modified Langmuir's equation based on a dual‐site model was employed for predicting the competitive adsorption isotherm, and the isotherm was clearly described by the equation. The theoretically estimated amount of adsorbed water at the constant pw decreased slightly with increasing pc. The effect of this phenomenon on the sensitivity of the capacitive‐type relative humidity sensor was examined. As expected, the electrical capacitance of the sensor at the constant relative humidity decreased because of the coexistence of CO2 gas. However, the influence was quite small in the CO2 concentration range in the ordinary environment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 401–407, 2002 相似文献
17.
Yinxiang Lu Altan Bolag Jun-ichi Nishida Yoshiro Yamashita 《Synthetic Metals》2010,160(17-18):1884-1891
2,2′-(1,4-Phenylene)bis(2,3-dihydro-1H-naphtho[1,8-de]-1,3,2-diazaboroine) [PND] and 2,2′-(4,4′-biphenylene)bis(2,3-dihydro-1H-naphtho[1,8-de]-1,3,2-diazaboroine) [BND] were synthesized and characterized by using differential scanning calorimetry (DSC) measurements, single crystal X-ray structure analysis, UV–vis absorption and electrochemical measurements, thin-film X-ray diffraction (XRD) and AFM studies. Organic field-effect transistors (OFETs) were fabricated by vacuum deposition with a bottom contact geometry using Au electrodes. Annealing treatment optimizes the organic active layer and increases the charge carrier mobility. Field-effect mobilities of 7.2 × 10?3 for PND and 4.1 × 10?4 cm2 V?1 s?1 for BND were found. 相似文献
18.
The sorption behavior of CO2 gas in photocrosslinked poly(vinyl cinnamate) film was examined under atmospheric pressure. The sorption isotherm was well described by the Langmuir equation, suggesting that sorption of CO2 is mainly governed by adsorption in the microvoids. The amount of sorbed CO2 was significantly affected by the degree of crosslinking. The CO2 sorption was enhanced at a lower degree of crosslinking but was decreased at a higher degree of crosslinking. The unexpected increase in the amount of adsorbed CO2 correlated with the increase in the number of microvoids that occurred as a result of the crosslinking reaction. However, further crosslinking led to a decrease in the mean size of the microvoids. The smaller microvoids, in comparison to CO2 molecules, did not act as adsorption sites, so that the amount of sorbed CO2 decreased. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1744–1750, 2000 相似文献
19.
Ring-opening polymerization (ROP) of various oxirane derivatives of the type, 2,2-R1,R2-CCH2O
[R1 = H (1), CH3 (2); R2 = CH3 (a),
CH2Cl (b), CH2OCH3
(c)], using organotin phosphate (Bu2SnO-Bu3PO4)
condensate has been explored. The ROP of monosubstituted oxiranes (1a-c) afforded ring-opened polymers in high yields (1a,
1c = 99% and 1b = 69%); the resultant
polymers from monomers 1a and 1b possessed
high molecular weights (Mn = 9.49 × 104, 10.60
× 104, respectively). In contrast, both polymer yields and molecular
weights for resultant polymers in the polymerization of disubstituted oxiranes (2a-c) were considerably lower than those in the polymerization of monosubstituted
monomers (1a-c). ROP of glycidyl 2-methylglycidyl
ether (3) possessing two oxirane groups with different reactivity was
thus conducted by organotin catalyst; the high molecular weight polyether (Mn
= 9.17 × 104) containing oxirane ring in the side chain has successfully
been obtained in moderate yield. 相似文献
20.
Kitamura Y Shogenji R Yamada K Miyatake S Miyamoto M Morimoto T Masaki Y Kondou N Miyazaki D Tanida J Ichioka Y 《Applied optics》2004,43(8):1719-1727
The authors have proposed an architecture for a compact image-capturing system called TOMBO (thin observation module by bound optics), which uses compound-eye imaging for a compact hardware configuration [Appl. Opt. 40, 1806 (2001)]. The captured compound image is decomposed into a set of unit images, then the pixels in the unit images are processed with digital processing to retrieve the target image. A new method for high-resolution image reconstruction, called a pixel rearrange method, is proposed. The relation between the target object and the captured signals is estimated and utilized to rearrange the original pixel information. Experimental results show the effectiveness of the proposed method. In the experimental TOMBO system, the resolution obtained is four times higher than that of the unit image that did not undergo reconstruction processing. 相似文献