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51.
Three types of surfactants and related reference compounds containing sulfonate (-SO3Na), sulfate (-OSO3Na) or thioether carboxylate (-S-Cn-COOK) group were photodecomposed in an aqueous heterogeneous dispersion system. The photomineralization to SO42−ions was examined for the surfactants with different chemical structures. The photocatalytic activities of TiO2 and ZnO were compared for the sulfonates of dodecylbenzene sulfonate (DBS) and polystyrene sulfonate (PSS), the sulfates of sodium dodecyl sulfate (SDS), and the potassium salts of S-dodecylthioglycol acid (TGA), S-dodecylthiopropionic acid (TPA) and S-dodecylthiomalic acid (TMA). ZnO catalyst exhibited higher activity in the formation of SO42−ion than TiO2 catalyst.  相似文献   
52.
To evaluate the influences of O3, relative humidity (RH), and flow rate on the reaction between yellow sand and SO2, the SO2 deposition velocity and the oxidation state of sulfur were investigated by means of exposure experiments in a cylindrical flow reactor. Early in the reaction, the deposition velocity was not influenced by the RH or the presence of O3; as the reaction progressed, however, the deposition velocity increased in the presence of O3 and at high humidity. The oxidation of sulfur from S(IV) to S(VI) was also enhanced under these conditions. The amount of sulfur oxidation was positively correlated with the amount of deposited O3. Furthermore, the SO2 deposition velocity increased with increasing flow rate. However, changes in the flow rate had no noticeable effect on the amount of SO2 oxidation.  相似文献   
53.
54.
Oceanic squid do fly   总被引:1,自引:0,他引:1  
Using powerful jet propulsion, some squid species are able to exit the water and become airborne; this is a common behavior seen throughout the world’s oceans. However, direct scientific observation is rare, with most studies relying on anecdotal evidence and limited photographic documentation. Here, we examine the flying behavior of young oceanic squid (Ommastrephidae) observed in sequential photographs taken in the Northwest Pacific (35o34.0′N, 146o19.3′E) on July 25, 2011. We define four phases in the flight process: launching, jetting, gliding and diving. During flight, squid actively change their aerial posture and attitude depending on the flight phase and their distance from the water. The present study demonstrated that flight of squid is not simple gliding after incidental exit from the water, but involves jet propulsion, generation of lift force and control of different body postures in different flight phases, which have evolved to enhance escape from predators.  相似文献   
55.
This study aimed at clarifying the impact of deforestation and afforestation on the quality of life in a village in Sichuan Province, China. We devised a conceptual model of bioresource production and use based on quantified energy flow. The basic structure of the model has three sectors: production, use, and externals. We developed comprehensive methodology to quantify the model. Bioresource use per person in 1997 was 3.7 GJ for food, 10.2 GJ for fodder, 0.2–0.4 GJ for building material, 12.8 GJ for fuel, and 1.8 GJ for fertilizer, totaling 28.6–28.8 GJ.We used four environmental indicators to evaluate bioresource production and use: a biological productivity indicator, a use-efficiency indicator, a supply–demand balance indicator, and a self-sufficiency indicator. Use of these indicators showed that supply-demand balance of fuel was dramatically improved from 30% to 85% by afforestation, but 99% of bioresource use still depends on domestic products. Thus, it is necessary to improve biological productivity and promote the efficient use of bioresources to achieve sustainable living in the area. Massive deforestation in the 1950s caused a direct shortage of building material and fuel wood. The shortage of wood led to a stagnation in the rebuilding of houses, and fuel wood was substituted with crop residues. Because crop residues had been used for fertilizer and fodder, their use as fuel caused a shortage of fertilizer and fodder. This was an indirect impact of deforestation on peoples quality of life.  相似文献   
56.
Apple farmers in Kazuno, northern Japan, have started to grow peaches in the northernmost climatic region suitable for peach farming. Here, we investigate the process from the initial introduction of peach cultivation to its diffusion focusing on the farmers’ perceptions of climatic and non-climatic stimuli and their actions to respond to these stressors. Interviews with the farmers identified three distinct groups. Four farmers (Group 1) initiated the transition to peach production, which then spread to other farmers (Group 2) via personal connections. Later, after the provision of various means of support from the local government and the producers’ cooperative, many more apple farmers (Group 3) decided to begin peach production. Most farmers recognized the risk of damages to apple production as a result of typhoons and drought. However, only Group 1 farmers, who depend on direct sales to customers, mentioned these climate-related damages as a reason to shift toward peach cultivation in order to maintain their customers. The peach fruit was specifically chosen as a replacement for apple because it is less vulnerable to these climatic stressors. For Group 3 farmers, the financial losses associated with these climate-related events could be compensated for by insurance. Their decision to grow peach is largely due to its higher price and immunity against a specific disease which affects apples but they only shifted once institutional support was available, thereby reducing the risk in cultivating a new species. Our findings suggest that the role of institutions was not to drive the process of the adaptation itself but rather to provide relevant support to farmers to enable them to shift to new crop varieties more easily. We argue that such process-based understanding is crucial in formulating strategies to increase adaptive capacity in agriculture.  相似文献   
57.
Diarrheal diseases can be transmitted via both primary infection due to exposures to contaminated materials from the environment and secondary infection due to personto-person contacts. Usually, the importance of secondary infection is empirically assessed by fitting mathematical models to the epidemic curves. However, these empirical models may not be applicable to other epidemic cases because they are developed only for the target epidemics and they don't consider the detail routes of infection. In our previous study, we developed a theoretical model taking into account the various routes of infection that commonly occur in households(e.g., shaking hands, food handling, and changing diapers).This model was made flexible and applicable to any epidemics by means of adjusting model parameters. In this study, we proposed a new index "Vulnerability indicator to secondary infection(VISI)", which expressed a ratio of secondary infection to primary infection risks and calculated this index in a simulated norovirus(No V) epidemic that involved 10,000 households.The results demonstrated that households composed of more than three members including infant(s) had much higher levels of VISI(5–45) than two-member-households with VISI(0.1–4).These results concluded that the infants were likely to be a hub of secondary infections in highly dense families and therefore careful handling of diapers was deemed indispensible in such families to effectively control the secondary infections.  相似文献   
58.
Environmental Science and Pollution Research - We assessed the contamination, dynamics, and health risks of the pesticides cyanazine, simetryn, fenarimol, isoprothiolane, diazinon, irgarol,...  相似文献   
59.
Fish samples purchased from Japanese markets were analyzed for Dechlorane Plus (DP)(syn-, anti-), polybrominated diphenyl ether (PBDE), and hexabromocyclododecane (HBCD)(α, γ). Twenty fish were analyzed using gas chromatography-mass spectrometry for DP and PBDE, and using liquid chromatography-tandem mass spectrometry for HBCD. DP was detected in 18 samples and ∑DP concentrations were <0.2-14.2 pg g−1 wet wt. Among the DP isomers, anti-DP was the dominant residue observed in this study. PBDE was detected in all samples. Concentrations of ∑PBDE ranged from 2.2 to 878 pg g−1 wet wt. HBCD was detected in 18 samples, and ∑HBCD concentrations were <0.02-21.9 ng g−1 wet wt. In fish landed near the East China Sea and the Sea of Japan, we detected relatively high concentrations of DP, PBDE, and HBCD. These results indicate that the seawaters around East Asia are contaminated with flame retardants. This study demonstrates the presence of DP in fish marketed in Japan for the first time.  相似文献   
60.
Individuals’ exposure to various persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), and its adverse health effects have been a cause of concern. We measured blood PCB concentrations from samples taken from 507 Japanese individuals ranging from infants to those over 80 years of age. The blood PCB levels increased with age for both male (Spearman’s r?=?0.69, p?<?0.001) and female (Spearman’s r?=?0.70, p?<?0.001) participants. Adult men and nulliparous women showed similar increases with age. However, the PCB levels of multiparous women were lower than those of nulliparous women in their thirties (p?=?0.005), probably because the PCBs were transferred from the mothers to their children during pregnancy and lactation. Among infants (<2 years of age), some had as high levels of accumulated PCB levels as those in adults >30 years of age. In some cases, the PCB levels were over 0.8 ng/g wet weight, similar to levels observed in adults over 50 years of age. In the future, it will be necessary to do research on the health of the children who are exposed by high concentration level of POPs.  相似文献   
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