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371.
Since the 1980s, the increase of Asian migrants in large cities has contributed significantly to the cultural landscape of
Australia, especially in the city suburbs. Based on the Census and in-depth interviews of 103 Taiwanese migrants, this research
examines the location decisions and residential preferences of Taiwanese migrants in Sydney, Brisbane and Melbourne. The reasons
for choosing the state, the particular city, and specific area of residence are probed into. The survey shows that migrants
moved to Australia mainly for children’s education, lifestyle and political instability reasons. The main reasons for choosing
to settle in Sydney were favourable business opportunities, and the northern part of Sydney was preferred. Those who chose
Brisbane are attracted by the good climate there, and the residents preferred the Sunnybank area. Melbourne was chosen for
the good education it offers, and areas on transportation lines near good schools are selected. Choice of residence was based
mainly on their needs and their resources which may change over time. In general, they always choose to locate in close proximity
to their family, friends and Taiwanese communities. Their locational choice depends on income and housing budget, proximity
to good schools and shopping centers, and information from friends or earlier migrants. Based on such factors, this study
clearly demonstrates that the Taiwanese immigrants are fundamentally different from early Chinese settlers who once aimed
to settle at Chinatown locations. 相似文献
372.
Surface and gravity-cored sediments were collected from the Kaoping coastal area off southwestern Taiwan to determine particle size, organic carbon, trace metal concentration and enrichment factor (EF), 210Pb dating, and 206Pb/207Pb ratio for determining present and historical metal pollution. Surface distributions of trace metals ranged from 0.02 to 0.13 mg/kg for Cd (EF: 0.16-1.65), from 35 to 189 mg/kg for Cr (EF: 0.85-2.92), from 25 to 64 mg/kg for Ni (EF: 0.53-2.38), from 10 to 32 mg/kg for Pb (EF: 1.20-4.94), and from 29 to 129 mg/kg for Zn (EF: 1.18-3.50). Trace metal concentrations correlate closely with distributions of mud (<63 microm) and organic carbon which accumulate largely around river mouths and within the Kaoping Canyon. With the exception of Cd, Cr and Ni in certain areas with rather coarse sediments, metals were generally elevated above the baseline levels over the studied area. Metals were also relatively enriched in areas with high contents of mud and organic carbon. Sedimentation rates derived from the excess 210Pb data in core sediments sampled from the canyon illustrate metal pollution beginning around 1970 that is corresponding to the booming time of economic growth in Taiwan. Meanwhile, the status of Pb pollution in core sediments is verified by an inversed correlation between 206Pb/207Pb ratios and Pb concentrations. Anthropogenic Pb and other metals in the studied area were apparently derived primarily from the Kaoping River and accumulated around the river mouth and within the Kaoping Canyon. The Kaoping Canyon appears to act as a major sink for river borne trace metals. 相似文献
373.
New evidence for covalent coupling of peptides to humic acids based on 2D NMR spectroscopy: A means for preservation 总被引:1,自引:0,他引:1
Pang-Hung Hsu 《Geochimica et cosmochimica acta》2005,69(18):4521-4533
Nitrogen immobilization in soils and sediments involving the preservation of peptides is an important yet not well-understood process. Several hypotheses have been proposed for the preservation of peptides in these systems; however, to date, there is no direct molecular-level evidence for any one of several hypotheses. In this study, a synthesized peptide with 15N-labeled amino acid residues was utilized to examine the mechanism by which humic substances from a peat might chemically interact with peptides to induce preservation. Two-dimensional 15N-1H HSQC NMR experiments were performed to evaluate the bonding and nonbonding interactions between 15N-labeled peptide and an Everglades peat humic acid. The observed changes in cross peaks provide the first direct spectroscopic evidence for what we believe to be covalent binding between these substances. Noncovalent interactions between the 15N-labeled peptides and humic acid molecules are also observed in the spectra. Quinone structures in humic acids are suggested to be the important reactive groups, based on reaction of the labeled peptide with a model quinone which shows similar nitrogen-proton correlated peak patterns as is observed in the HSQC NMR spectra of humic acids reacted with the peptide. The Michael reaction with quinone structures is proposed, and this type of reaction provides a mechanism that is consistent with previous observation for the chemistry of sedimentary nitrogen species. 相似文献
374.
Albert S. Chen Ming-Hsi Hsu Wei-Hsien Teng Chen-Jia Huang Sen-Hae Yeh Wan-Yu Lien 《Natural Hazards》2006,37(1-2):107-132
The structural measure was the major solution for flood defense in Taiwan. However, the measure is always limited to the design
standard and cannot prevent the damages when floods exceed certain scale. Therefore, non-structural measures for flood mitigation
are the indispensable complements to structural solutions. The study introduces the establishment of inundation potential
database that provides required information for the non-structural measures in Taiwan. The database was built by numerical
simulations, based on different rainfall scenarios, and has been applied by the local governments of Taiwan for land use managements,
flood warning systems, emergency responses, and flood insurance programs to reduce the flood damages and impacts. 相似文献
375.
Covalent and non-covalent interaction of proteinaceous materials in soils and sediments has been suggested as an important mechanism for immobilizing nitrogen in numerous types of environments. In a previous study (Hsu P.-H., Hatcher, P.G., 2005. New evidence for covalent coupling of peptides to humic acids based on 2D NMR spectroscopy: A means for preservation. Geochimica et Cosmochimica Acta 69, 4521–4533), we provided molecular evidence for covalent, as well as non-covalent, bonding between 15N-labeled peptides and humic acid molecules using the 2D HSQC (heteronuclear single quantum coherence) NMR technique. In this report, we examine the influence of aromaticity and aliphaticity of peptides and humic materials on these covalent and non-covalent interactions. We use 2D NMR techniques to evaluate bonding interactions of 15N labeled peptides, having different aromatic and aliphatic properties, with three humic acids that vary in degree of aromaticity. The peptide containing primarily aromatic amino acid residues is observed to form covalent and non-covalent bonds with mainly aromatic-rich humic acids. The peptide composed of aliphatic amino acid residues shows, on the other hand, only bonding interactions with aliphatic-rich humic acids. These observations provide the first direct molecular evidence that aliphatic functional groups are involved in bonding with proteinaceous materials. The process may play an important role in sequestration of proteinaceous materials in sedimentary systems such as marine systems where the humic materials are mainly aliphatic in nature. 相似文献
376.
Many researches mention the land development in the watershed increases the peak flow rate and volume of the surface runoff. However, another phenomenon, the land development in the lowlands with filling method probably results in flood risk transfer effect, is rarely mentioned. This study took Heshunliao Farm as study object and used SOBEK model to assess the phenomenon. The terrain of this farm was flat and low, at an elevation of about 1.3–3 m before development. A filling method has been adopted to raise the surficial elevation in the development zone to 3–5 m. The western end of the development zone is still maintained its original elevation. The storm sewer system, detention basin, and pumping stations have been built in the development zone. There are two effects in the development of the low-lying land. One is the increase in the peak outflow rate in the development zone. Under a 10-year return period rainfall, the peak outflow rate after development has increased to 9.94 cm, compared to 2.62 cm when there was no development. Another effect is that the disappearance of the original flood-accumulated space due to land development activities transfers the risk of flooding to the surrounding land. Under a 10-year return period rainfall, the flooded area of the developed area was reduced from 78.4 ha before land development to 0.32 ha after the development, while the flooded area of the western end of the development zone increased from 13.28 ha before development to 27.20 ha after development. 相似文献
377.
In August 2009,Typhoon Morakot brought a large amount of rainfall with both high intensity and long duration to a vast area of Taiwan.Unfortunately,this resulted in a catastrophic landslide in Hsiaolin Village,Taiwan.Meanwhile,large amounts of landslides were formed in the Jiaopu Stream watershed near the southeast part of the Hsiaolin Village.The Hsiaolin Village access road(Provincial Highway No.21 and Bridge No.8) was completely destroyed by the landslide and consequent debris flow.The major scope of this study is to apply a debris flow model to simulate the disaster caused by the debris flow that occurred in the Jiaopu Stream during Typhoon Morakot.According to the interviews with local residents,this study applied the destruction time of Bridge No.8 and Chen's house to verify the numerical debris flow model.By the spatial rainfall distributions information,the numerical simulations of the debris flow are conducted in two stages.In the first stage(before the landslide-dam failure),the elevation of the debris flow and the corresponding potential damages toward residential properties were investigated.In the second stage(after the landslidedam failure),comparisons of simulation results between the longitudinal and cross profiles of the Jiaopu Stream were performed using topographic maps and satellite imagery.In summary,applications of the adopted numerical debris flow model have shown positive impact on supporting better understanding of the occurrence and movement of debris flow processes. 相似文献
378.
内蒙古伊盟盐海子YaO2孔氧碳同位素记录的第四纪末次冰期及全新世气候特征 总被引:2,自引:0,他引:2
从内蒙古伊盟盐海YaO2孔氧碳同位素资料中可以看到:东亚季风气候在22 000aBP时由第四纪末次冰期气候开始转入末次间冰期气候。东亚季风带第四纪末次冰期时的气候环境是湿冷的淡化期。而末次间冰期的气候环境是热干的成盐期。其次,末次冰期以来,气候由湿冷转变为热干,5400aBP时气候达到热干的大暖期的最热点。之后又逐级降至现代暖趋冷的气候特征。东亚季风气候带的末次间冰期开始界线在22 000aBP左右。δ18O资料告诉我们内蒙古高原第四纪末次冰期曾有过冰川或冰盖地貌景现,在22000aBP以后才消融进入第四纪末次间冰期。 相似文献
379.
380.
An experimental scheme was designed to obtain laboratory-scale verification of Hasselmann's nonlinear wave—wave interaction and white-cap dissipation theories. Water wave height and fluctuating air pressure were measured simultaneously in a fixed reference frame as a function of fetch in the Stanford Wind, Water-Wave Research Facility under the conditions of a steady wind and a stationary wave spectrum. All the data were obtained 5 mm above the highest point of the wind waves for five stations (3 m apart on average) and at three wind speeds (7.1, 8.0 and 8.9 m/sec). The wave height and fluctuating pressure were measured by a capacitance wave-height gauge and a crystal pressure transducer, respectively.Based on the experimental results, Hasselmann's nonlinear wave—wave interaction theory appears to be valid. Barnett's approximate parametric equation for calculating the energy transfer of nonlinear wave—wave interaction and Hasselmann's white-capping dissipation model were also verified and appeared to be applicable in the relatively low and intermediate frequency region of a wave spectrum for a normalized fetch range of 100–500. Based on the results of an overall energy balance in a gravity wind-wave spectrum, the nonlinear wave—wave interaction mechanism is shown to play a dominant role in the energy transfer processes after the wave spectrum is generated. 相似文献