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121.
Yamaoka  Kazue 《Behaviormetrika》2000,27(2):125-151

This paper discusses the acculturation of Japanese descents through the approach of exploratory data analysis. When considering acculturation, it may be common sense to consider that Sansei are more assimilated with the culture of the immigrated country than are Nisei. While observing the survey results, the question “Is this really true?” occurred to me. The point of the study is to examine, by extensive sample surveys, the hypothesis that acculturation among generations of immigrants is of two types, namely: ‘natural acculturation’ and ‘a tendency of turning toward the Japanese way of thinking.’ This is considered to be an important point when the acculturation of a race is considered.

The author deals with the degree of acculturation among generations of Japanese Americans and Japanese Brazilians, based on international comparative survey results among the host society, ethnic society and different immigrant groups consisting of several generations.

The results supported the hypothesis that acculturation among generations of immigrants is of two types. Possible factors related to socio-education may also exert effects on their attitudes and values.

  相似文献   
122.
Various terpene alcohols were prepared from isoprene oligomers via two steps: epoxidation with peracetic acid and isomerisation with aluminium triisopropoxide. For example, 2-methylene-6-methyl-7-octene-1-o1 was prepared from 2,6-dimethyl-1,7-octadiene. From 2,6-dimethyl-2,7-octadiene, 3,3,6-trimethyl-1,5-heptadiene, 2,7-dimethyl-2,6-octadiene, 2,6-dimethyl-1,3,6-octatriene, 1-methyl-4-isopropenyl-1-cyclohexene, and 1,5-dimethyl-1,5-cyclooctadiene, the corresponding alcohols were obtained, respectively.  相似文献   
123.
Dynamic mechanical properties of photopolymerizable poly(vinyl alcohol) (PVA)–monoacrylate blends were investigated by measuring dynamic shear modulus G′ and loss tangent, tan δ. The dynamic mechanical properties of the blends before being exposed to UV irradiation were governed by the weight percent of the monomers which act as plasticizers. On the other hand, the UV-irradiated blends seemed to be typical two-phase materials since they revealed two tan δ maxima whose positions were independent of the monomer content. Those two maxima were assigned to PVA and photopolymerized acrylates with reference to the dynamic mechanical data of PVA and a PVA-polyacrylamide polyblend. Those dynamic mechanical data suggested that insolubilization of the blend type photopolymers should be caused by a decrease in solubility due to graft polymerization of acrylate monomers onto PVA.  相似文献   
124.
To characterize the highly nonlinear hysteretic behavior of high damping rubber (HDR) bearings, a previously developed mathematical hysteresis model, rather than a simplified bilinear hysteresis model, is adopted in this study. Unilateral and bilateral seismic simulation tests of a scaled-down multistory structure isolated with HDR bearings subjected to three recorded earthquakes were conducted. Based on the unilateral test results, different sets of model parameters can be identified. The fidelity of the adopted hysteresis model is investigated by comparing the analytical predictions using all sets of identified parameters with results measured from the tests. The significant influence ascribed to different ground motion characteristics such as the effects of near-field and far-field earthquakes on modeling the hysteretic behavior of HDR bearings is observed. Besides, a feasibility study on applying the identified parameters of the adopted hysteresis model to predict the bilateral seismic responses is performed. Even though the prediction accuracy of the seismic responses is satisfactory in two orthogonally horizontal directions, the bilateral hysteretic modeling of HDR bearings requires further intensive studies considering the coupling effect under bilateral excitations.  相似文献   
125.
This paper introduces the new synthetic methodology of polyolefin-based block and graft copolymers with polar segments [e.g., polystyrene and poly(meth)acrylates]. Various brominated polyolefins were prepared by bromination of polyolefins with N-bromosuccinimide. The resulting brominated polyolefins were able to initiate the controlled radical polymerization of polar monomers, such as methyl methacrylate, ethyl acrylate, t-butyl acrylate, styrene and 2-(dimethylamino)ethyl acrylate, using a CuBr/N,N,N′,N″,N″-pentamethyldiethylenetriamine catalyst system, leading to a variety of polyolefin-based copolymers with a different content of the corresponding polar segment. Because of the accessible synthesis of polyolefin macroinitiators, this synthetic methodology is expected to result in the preparation of a wide range of polyolefin-based block and graft copolymers.  相似文献   
126.
In order to improve some inferior physical properties of bacterial poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) [P(3HB‐co‐3HHx)] by blending with PEO, the miscibility, spherulite morphology, crystallization behavior and mechanical properties of P(3HB‐co‐3HHx)/PEO binary biodegradable polymer blends were investigated. A good miscibility between P(3HB‐co‐3HHx) with a 3HHx unit content of 11 mol‐% and PEO in the amorphous state was found when the PEO weight fraction was 10 wt.‐%, while the miscibility decreased dramatically when the PEO weight fraction exceeded 20 wt.‐%. Strongly depending on the blend composition, the mechanical properties of P(3HB‐co‐3HHx) was found to be significantly improved by blending with PEO with a weight fraction of ≈5–17.5 wt.‐%.

  相似文献   

127.
Twenty-three tube deposits taken from seven heat-recovery boilers of municipal solid waste incinerators were examined by chemical analyses and X-ray diffraction. These deposits were measured by Differential Scanning Calorimeter (DSC) in N2 to investigate their melting characteristics. Sixteen deposits were used to evaluate their corrosiveness to carbon steel by high-temperature corrosion test conducted at 400 °C for 20 h in 1500 ppm HCl – 300 ppm SO2 – 7.5%O2 – 7.5%CO2 – 20%H2O – N2. Total heat of endothermic reactions of the deposits taking place between 200 and 400 °C can be related to the corrosion rate of carbon steel at 400 °C. Corrosion initiated at temperatures when the deposits started to melt, became severe when fused salt constituents increased, and alleviated when the majority of the deposits became fused. The corrosion can be interpreted as fused salt corrosion caused by chloride and sulfate salts.  相似文献   
128.
We investigate deformation-induced martensitic transformation behavior in cold-rolled and cold-drawn specimens of type 316 stainless steel. Deformation-induced martensite preferentially nucleates at the twin boundary between the austenite matrix and a deformation twin. In the cold-rolled specimen, martensite formed at the twin boundary has a Kurdjumov–Sachs (K–S) relationship with both the austenite matrix and the deformation twin (“double K–S relationship”). In the cold-drawn specimen, two kinds of deformation twins with different twin planes are typically formed, and therefore deformation-induced martensites are formed where the deformation twin boundaries intersect: martensite thus has an imperfect “triple K–S relationship” with the austenite matrix and the two deformation twins. The complicated crystallographic orientation relationship between austenite and martensite grains strongly restricts the formation of some variants of deformation-induced martensites. Because of the difference in number of nucleation sites in the cold-drawn and cold-rolled specimens, martensitic transformation is more enhanced in the former than in the latter.  相似文献   
129.
Two genes encoding acyl-CoA dehydrogenases, acdA and acdB, arranged in tandem, were found in the chromosomal DNA of Acinetobacter sp. strain M-1. AcdA was purified from the parental strain and AcdB was purified from an Escherichia coli strain expressing the cloned gene. The substrate specificities of the two enzymes suggest that AcdA is a medium-chain acyl-CoA dehydrogenase and that AcdB is a long-chain acyl-CoA dehydrogenase. Characterization of n-alkane metabolism in Acinetobacter sp. strain M-1 has revealed parallel pathways as well as enzymes with overlapping specificities in a single pathway. The two acyl-CoA dehydrogenases described here provide another example of the physiological complexity underlying n-alkane utilization.  相似文献   
130.
Methyl formate synthesis during growth on methanol by methylotrophic yeasts has been considered to play a role in formaldehyde detoxification. An enzyme that catalyses methyl formate synthesis was purified from methylotrophic yeasts, and was suggested to belong to a family of alcohol dehydrogenases (ADHs). In this study we report the gene cloning and gene disruption analysis of three ADH-encoding genes in the methylotrophic yeast Candida boidinii (CbADH1, CbADH2 and CbADH3) in order to clarify the physiological role of methyl formate synthesis. From the primary structures of these three genes, CbAdh1 was shown to be cytosolic and CbAdh2 and CbAdh3 were mitochondrial enzymes. Gene products of CbADH1, CbADH2 and CbADH3 expressed in Escherichia coli showed both ADH- and methyl formate-synthesizing activities. The results of gene-disruption analyses suggested that methyl formate synthesis was mainly catalysed by a cytosolic ADH (CbAdh1), and this enzyme contributed to formaldehyde detoxification through glutathione-independent formaldehyde oxidation during growth on methanol by methylotrophic yeasts.  相似文献   
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