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51.
A hill station is a town or city situated in mountain regions in the tropics founded during the western colonization in the nineteenth and early twentieth centuries. Hill stations have moderate temperatures, and are known for their relatively good natural environments, which generate valuable ecosystem services that benefit the local population. However, rapid urbanization threatens the sustainability of these areas. This study evaluates the sustainability of the urbanization process of Baguio City, a hill station city in Southeast Asia and the summer capital of the Philippines, by determining the relationship between its velocity of urbanization and velocity of urban sustainability based upon various perspectives. From an equal weight perspective (of the triple bottom line of sustainability components, namely environmental, social, and economic) and a pro-economic perspective, the results revealed that the urbanization of Baguio City has been moving toward a “sustainable urbanization.” However, from the environmental and eco-sustainable human development perspectives, the results indicated that it has been moving toward an “unsustainable urbanization.” The paper discusses the implications of the findings for the planning of sustainable development for Baguio City, including some critical challenges in sustainability assessment and the applicability of the framework used for future sustainability assessments of the other hill stations in Southeast Asia.  相似文献   
52.
采用混凝剂对皮革废水进行混凝处理。对3种无机混凝剂和一种有机混凝剂进行了筛选,研究了pH值和投药量对废水中SS、COD、铬和色度等污染物去除效果的影响。结果表明,当pH值在酸性和中性时,效果不明显;当pH值为碱性时,效果显著。硫酸亚铁、硫酸亚铁+PAM和聚合氯化铝(PAC)+PAM 3种混凝剂组合具有良好的混凝效果,在合适的pH值和投药量下,SS和COD的去除率分别达到80%和30%以上,铬和色度的去除率分别达到95%和50%以上。且硫酸亚铁混凝效果好,成本低,适合小型皮革企业需求。  相似文献   
53.
Ninh TD  Nagashima Y  Shiomi K 《Chemosphere》2008,70(7):1168-1174
Nine species of sea anemones (Anthopleura asiatica, Actinia equina, Actinodendron arboreum, Phymanthus loligo, Entacmaea actinostoloides, Stichodactyla gigantea, S. haddoni, S. mertensii and Metridium senile) contained arsenic in the range of 1.6-7.0microg As g(-1) (wet mass basis). Irrespective of the species, water-soluble arsenic compounds accounted for more than 80% of the total arsenic. Analysis of water-soluble arsenic compounds by LC/ESI-MS revealed that four arsenicals, arsenobetaine (AB), trimethylarsoniopropionate, arsenocholine (AC) and tetramethylarsonium ion (TEMA), are contained in most species but arsenate, methylarsonic acid, dimethylarsinic acid and trimethylarsine oxide are absent in all species. Interestingly, compositional patterns of the four arsenicals greatly differed from species to species. Only three species (S. gigantea, S. haddoni and M. senile) contained AB at the highest proportions, similar to the majority of marine animals. However, the remaining six species showed unusual compositional patterns of arsenic compounds; AC was most predominant in A. arboreum and P. loligo and TEMA in A. asiatica, A. equina, E. actinostoloides and S. mertensii. On the whole, high proportions (24.6-87.1% of the water-soluble arsenic) of TEMA appear to be a peculiar characteristic of many species of sea anemones. Thus, sea anemones are an important animal group in the arsenic cycling, especially in that they may be donors of TEMA to predators.  相似文献   
54.
The state of mixture of light-absorbing carbonaceous particles was investigated in relation to light absorption properties using electron microscopic examinations, black carbon (BC) analyses of quartz filter by thermal/optical reflectance (TOR) method, measurements with two continuous light-absorbing photometers at a suburban site of Tsukuba, about 60 km northeast of Tokyo. The volume fraction of water-soluble material (?) in individual particles is important for assessing particulate light-absorbing and/or scattering of atmospheric aerosols. The values of ? in BC particles were evaluated by electron micrographs before and after dialysis (extraction) of water-soluble material. The mass absorption coefficient (MAC in units of m2 g?1) tended to increase with increasing the average ? in BC particles with the radius range of 0.05–0.5 μm. Thus, our results indicate that coatings of water-soluble material around BC particles can enhance the absorption of solar radiation. Moreover, the single scattering albedo (SSA) will increase because a large amount of coating material will scatter more light.  相似文献   
55.
Dimethyl ether (DME) has been focused as a substitute for diesel fuel, and a number of studies have investigated engines fueled with DME because DME has a low auto-ignition temperature and does not generate particulate matter (PM). Therefore, in the last few years, the construction of DME filling stations for trucks in Japan has been planned. The introduction of DME vehicles requires expansion of DME supply stations, which in turn requires the collection of safety data and the establishment of safety regulations. The present paper describes an experimental investigation of the hypothetical scenario in which liquid DME is accidentally released and an explosion occurs. In the present study, large-scale leakage and ignition of DME were investigated and flame propagation data was obtained. We also measured the overpressure of the blast wave and the heat flux from the fireball. When the ignition position is near the nozzle, the flame propagation velocity is higher. The overpressure from the DME fireball is stronger than that from DME/air mixture deflagration. In summary, these results provide safety data for safety management of DME filling stations.  相似文献   
56.
主要考察了尼克酰胺和核黄素提高红串红球菌USTB-03对4,6-二甲基二苯并噻吩(4,6-DMDBT)脱硫活性的效应。研究结果表明,在培养基中添加初始浓度为10 mmol/L的尼克酰胺,脱硫比活性由原来302.4 mmol 4,6-DMDBT/(kg细胞干重·h)增加到476.4 mmol 4,6-DMDBT/(kg细胞干重·h),提高了57.5%。添加初始浓度为25μmol/L的核黄素,脱硫比活性增加到了465.8 mmol 4,6-DMDBT/(kg细胞干重·h),提高了54%。无论是采用微量的尼克酰胺或核黄素都可以大幅度提高红串红球菌USTB-03对4,6-DMDBT的脱硫活性,在此研究领域尚未发现有研究报道。尼克酰胺和核黄素分别是NAD和FMN的主要成分,可以促进脱硫关键辅酶FMNH_2的生物合成,因此,大幅度提高了红串红球菌USTB-03对4,6-DMDBT的脱硫活性。  相似文献   
57.
Structure design of a photosynthetic-based biofuel cell and the fabrication processes to make it have been explored and developed. Novel nanostructure and modified polyaniline have been used to enhance the performance of the biofuel cell. The mechanism of the electron transfer process and the electrocatalysis of polyaniline have been investigated. Photosynthetic-based biofuel cells with a mA/cm2 current density have been demonstrated.  相似文献   
58.
The disposal of wood waste treated with chromated copper arsenate (CCA) is a problem in many countries. We have proposed a novel chelating extraction technique for CCA-treated wood using bioxalate, a solution of oxalic acid containing sufficient sodium hydroxide to adjust the pH to 3.2, which is an effective way to obtain an extraction efficiency of 90% for chromium, copper, and arsenic. The purpose of the present study was to investigate the characteristics of bioxalate extraction of CCA-treated wood. Extractions of CCA-treated western hemlock chips with solutions of bioxalate, oxalic acid, and sodium hydroxide were carried out. The use of bioxalate was confirmed as the most effective extraction technique for chromium, copper and arsenic, with an efficiency of 90%. Extraction with simple oxalic acid was ineffective for copper (less than 40% extraction efficiency), but effective for chromium and arsenic, with 90% efficiency. Sodium hydroxide showed a similar tendency, being ineffective for chromium and copper (less than 20% extraction efficiency), but relatively effective for arsenic (around 70–80% efficiency). We also discovered an interesting phenomenon whereby the addition of sodium hydroxide to a simple oxalic acid solution during the oxalic acid extraction progress resulted in dramatically increased extraction efficiency for copper, chromium and arsenic, up to 90%. Although oxalic acid was ineffective for copper extraction, the addition of sodium hydroxide during the oxalic acid extraction process rendered it effective.  相似文献   
59.
We examined the effects of tributyltin (TBT) on embryonic development, hatching success and sexual differentiation in Japanese medaka (Oryzias latipes). Embryos (within 8h after fertilization) were exposed to TBT in ovo via nanoinjection at concentrations of 0 (control), 0.16, 0.80, 3.96, 19.2 and 82.1 ng/egg. Embryonic survival, development and hatching were observed. Hatched fry were reared until 60 days when they sexually matured, and sexual differentiation was also examined by accordance of genetic and phenotypic sex, based on existence of DMY (a male determining gene in medaka) and secondary sex characteristics. As results, TBT caused a concentration-dependent mortality and impaired the embryonic development. However, no masculinization was detected at 60 dph medaka adults. Lowest observed effective concentration for inducing abnormal embryonic development was estimated to 0.16 ng/egg (ca. 160 ng/g egg).  相似文献   
60.
Caenorhabditis japonica is a bacteriophagous nematode species that was discovered on the semi-social burrower bug, Parastrachia japonensis, which demonstrates egg-guarding and provisioning behaviors. To understand the life history of C. japonica in relation to P. japonensis, we demonstrated the specificity of this association and fluctuations in nematode number on the insect throughout the year. C. japonica dauer larvae (DL), larvae in a nonfeeding diapause stage, were predominantly found as clumps on the adult female insects but rarely found on the male insects in all populations examined. This female-biased association was consistent throughout the year, but after the nymphs hatched, nematodes were not detected on the mother insects showing provisioning behavior. DL appeared on the nymphs, and the number of DL on the newly emerged female insects gradually increased thereafter. C. japonica has never been detected on other invertebrates collected from the P. japonensis habitat thus far. Our data suggest that the life cycles of C. japonica and P. japonensis are synchronized.  相似文献   
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