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The objectives of this investigation were: (1) to examine the overall substrate removal of a three component mixture by an acclimated seed using total organic carbon measurements, (2) to observe the rates of removal of each of the three components in the mixture at four different food-to-microorganism ratios (F/M), (3) to show the effects of the composition of the substrate with varying degradability on effluent quality, and (4) to observe the effects of sludge age on total substrate removal.To accomplish these objectives, sludge from a municipal sewage treatment plant was acclimated as seed in a continuous flow, completely mixed laboratory reactor. A multicomponent substrate consisting of a mixture of glucose, phenol and sulfanilic acid, was fed at different F/M ratios. The removal rate was determined as total organic carbon and specific analytical measurements for each substrate in the influent and effluent samples were also made. Various combinations of glucose, phenol and sulfanilic acid were used as a substrate in three runs. This made it possible to observe the removal rate of each substrate in the mixture as related to their individual biodegradability as well as their influent concentrations.The results showed that for the three substrates employed in this study, the overall removal rate, in terms of total organic carbon in a mixed acclimated culture, is the sum of the individual specific removal rates. The effluent quality in terms of soluble TOC was related to the F/M or to the sludge age using Eckenfelder's kinetic model.  相似文献   
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The LaNi5 intermetallic compound is an AB5 type hydrogen storage alloy which exhibits low operating temperature, easy activation, low pressure and tolerance to impurities. In this study, LaNi4.7-x Al0.3Bix (x = 0.0, 0.1, 0.2, 0.3) alloys were produced by melt-spinning technique and the effects of Al and Bi additions on the microstructure, thermal and hydrogen storage properties of LaNi5 were investigated. The results showed that substitution of Ni with Al led to a desired decrease in absorption/desorption plateau pressure and hysteresis without a decrease in hydrogen storage capacity. In contrast, Bi substitution with Ni increased the absorption/desorption plateau pressure, reduced the hydrogen capacity and increased pulverization resistance of the alloy due to the formation of BiLa and AlNi3 intermetallic phases at the grain boundaries.  相似文献   
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Does globalization have a positive or negative impact on democracy? One reason this problem has gone unsolved is found in the fact that most studies to date have not made systematic use of empirical data to test propositions concerning the relationship between globalization and democracy. While there have been studies that have made a pioneering systematic contribution through the use of macroeconomic and other aggregate statistics, this article empirically examines whether globalization enhances or constrains democracy by using cross-national survey data collected in 17 countries (the Asia-Europe Survey). Our empirical testing has shown that globalization tends to be positively correlated to democratic activism at the individual level, suggesting the possibility that experiences of globalization strengthen democracy.

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A new calixarene-based donor-acceptor system, cone conformer 1, was prepared for the first time. In this compound, the calix[4]arene serves to juxtapose a tri-chloroquinone acceptor near the porphyrin photo-donor plane. As to the conformational control, the cone conformer 1 gave two peaks of phenolic OH groups at 8.40 and 8.43 ppm. This shows that cone conformer 1 is stabilized by intramolecular hydrogen bonds. The fluorescence intensity of 1 was 35% of that for the control compound 2. This means the tri-chloroquinone group in 1 efficiently quenched the fluorescence of ZnP*. The shortest edge-to-edge separation of the chromophores of 1 is ca. 8 A (as judged by CPK models). This provides a new calixarene-based supramolecular system in which through-space donor-to-acceptor electron transfer is observed upon photoexcitation.  相似文献   
58.
Poly(vinyl alcohol) was crystallized from its aqueous solution under a steady-state flow with different conditions. Using a differential scanning calorimeter (DSC), the thermal properties of PVA precipitates obtained by the flow-induced crystallization were measured, showing a single melting peak in the DSC curve. The melting temperature of PVA crystallized depended on the rate of stirring, crystallization temperature, concentration of PVA, yield of precipitates, and morphology of the crystals. Particularly, there was a closer relationship between the melting temperature and the yield of precipitates, i.e., it was through the effect on the yield of precipitates that crystallization conditions influenced the melting temperature. Generally, with certain conditions, the higher the yield of precipitates, the lower the melting temperature. Moreover, using electron microscopy, it was observed that there were some structural differences between the inner and outer sides of a PVA crystal mat round stirrer and between film-shaped and block-shaped crystals, leading to different melting temperatures. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1337–1344, 1997  相似文献   
59.
In the present work nano-sized powder of β-SiAlON was produced using a wet milling process. Different milling times and mediums (methyl ethyl keton, ethanol and toluene as solvents, polyethyleneglicol, oleic acid, sodium tripolyphosphate and polyvinylpyrrolidon as dispersants) were performed for the determination of the most efficient milling system. The powders were produced using a conventional process (the ball to powder ratio was 1:1.5, at 300 rpm, for 1.5 h) having a few hundred nanometer particle size, and these were used as standard powders in this study. The nano-sized β-SiAlON starting powders (<100 nm) were sintered at lower temperatures than that of the conventional powders. The amount of Y2O3 in powders (~130 nm), produced by high energy milling process, was fewer than conventional powders (5 wt.%). The results of the powder size, sintering behavior and mechanical properties of this sample were compared to those of the standard powder and its sintered sample. This sample, produced using the nano-powder, was investigated, and densified at 150 °C lower than that of the standard sample. Even though the amount of Y2O3 was decreased, the hardness of the samples was better than that of the standard sample.  相似文献   
60.
Experimental design was used to optimize the processing parameters for the decomposition of poly(vinyl chloride). Factorial design and face centered composite design (FCC) were applied to determine the optimum conditions. A total of 10 g PVC powder was mixed with different amounts of zinc stearate (ZnSt2) and natural zeolite and tested for thermal stability. Factorial fitted model was explained by first order pattern due to the significant main effect regression constants, and FCC model was described by second order model owing to higher order polynomial coefficients. FCC design was superior to factorial design as FCC considers not only its pure quadratic effects contribution but also its higher overall desirability for thermal stability of PVC. For factorial design the optimum conditions were determined as 163.06 mg for ZnSt2, 399.99 mg for zeolite, and 140°C for temperature with desirability of 0.933. However, 400 mg for ZnSt2, 333.24 mg for zeolite, and 140°C for temperature with desirability of 0.956 were obtained as the optimum conditions by FCC design. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
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