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11.
This study aimed to assess Japan’s recent “local production for local consumption” (LPLC) movement, with a special focus on vegetables in the Osaka city region of central Japan. After collecting statistics and spatial data, we conducted a multi-scale analysis of vegetable production and consumption along with the associated energy consumption, using geographical information system software at three spatial scales along the vegetable flow paths: national, regional, and local. Vegetables consumed in the Osaka city region came from prefectures throughout Japan, and we mapped the foodshed within this region at 1-km spatial resolution, as well as the distribution of farmland, farmers’ and other markets. We also conducted a scenario analysis for reduced energy consumption through organic farming and the utilization of abandoned farmland near a city to replace food imports from distant areas. We found that the large majority of vegetables consumed in the Osaka city region currently come from remote prefectures, and that this is associated with a high level of energy consumption. Inside the Osaka city region, peri-urban vegetable farming contributes to regional vegetable provision, resulting in an approximately 70 % production/consumption ratio within an 80-km radius of the urban center; if all of the area of abandoned farmland were restored to production, this ratio would increase to approximately 75 %. Organic farming activities that bring together farmers and urbanites are emerging in many parts of the study area, contributing to increased LPLC. Scenario analysis suggested that a decrease of more than 1 × 106 GJ of energy inputs could be achieved through wider adoption of local organic farming for local consumption and complete utilization of abandoned farmland in the Osaka city region.  相似文献   
12.

We evaluated the SARS-CoV-2-inactivation activity of ozonated glycerol (OG). When a viral solution with 1% fetal bovine serum (FBS) was mixed with test solutions at a ratio of 1:19 and incubated for 20 s, OG with ozone concentrations of over 1000 ppm inactivated ≥ 94.38% of the virus. Extension of the reaction time to 1 h led to the inactivation of ≥ 99.82% of the virus (the viral titer was below the detection limit). Extension to 24 h resulted in concentrations over 200 ppm OG inactivating ≥ 99.87% of the virus (the viral titers were below the detection limit). Next, viral solutions with 1, 20, and 40% FBS were mixed with test solutions at a ratio of 1:19 and incubated for 5 min. Whereas the virucidal activity of 500 ppm OG was very limited in the presence of 1% FBS (79.47% inactivation), it increased in the presence of 20 and 40% FBS (95.13 and 97.95% inactivation, respectively; the viral titers were not below the detection limit). Meanwhile, over 1000 ppm OG inactivated ≥ 99.44% of the virus regardless of the FBS concentration (the viral titers were below the detection limit). Extension of the reaction time to 1 h led to 500 ppm OG inactivating ≥ 99.91 and ≥ 99.95% of the virus with 20 and 40% FBS, respectively (the viral titers were below the detection limit). These results suggested that OG might be useful as a virucidal agent against SARS-CoV-2.

  相似文献   
13.
Concentrations and patterns of several chlorinated persistent organic pollutants (POPs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) and DDTs, HCHs, CHLs and HCB were determined in black-tailed gulls (Larus crassirostris) from breeding grounds in Hokkaido, Japan. Subcutaneous fat of five adult gulls was analyzed, which had different concentrations of target compounds, whereas gull eggs contained similar concentrations of target compounds. Similar congener profiles were found between adult gulls and eggs. The concentrations of non-ortho PCBs varied from 3.4 to 13.5 ng/g lipid weight (lw) in the fat of black-tailed gulls and from 2.4 to 7.4 ng/g lw in their eggs. 2,3,7,8-PCDD/Fs occurred at relatively lower concentrations than non-ortho PCB congeners in both adult gulls and eggs. The total TEQs (toxic equivalents, PCDD/Fs+ non-ortho PCB) ranged from 0.26 to 1.0 ng/g lw in adult gulls and ranged from 0.19 to 0.58 ng/g lw in eggs.  相似文献   
14.
The dust explosion committee of the Association of Powder Process Industry and Engineering, Japan recently established two testing standards for dust explosions. In the investigations for the standardization, many experimental data have been obtained for the dusts currently used in Japanese industries. Data for zirconium, tantalum and silicone dusts are presented to discuss the use of test methods, which have been accepted internationally. The test methods for dust explosions have to consider a variety of kinds and forms of dusts to be tested.  相似文献   
15.
The Philippine fisheries accounted for 3.7% of the gross national product at current prices. The sector employed about 990,872 persons. Of the divisions comprising the industry, municipal fisheries continued to contribute the largest share of fish production. However, the sector is beset with problems, many of which are best examplified by the case of San Miguel Bay (SMB). This paper presents the problems and constraints confronting SMB, a common property resource. This bay's open access condition has led to various problems, such as declining fishery resources, depressed socioeconomic conditions, illegal fishing, increasing population, and conflict among resource users. A poor marketing system, low level of fishing technology, fishermen's noncompliance and authorities' lax enforcement of rules and regulations, as well as lack of alternative sources of income further characterize the condition in SMB. Establishment of fishing rights, improvement of the marketing system, provision of alternative sources of income, and improvement of fishing technology were some of the solutions suggested. One major constraint, however, is financial, Comanagement complemented with other management tools has been proposed in addressing the problems in SMB.  相似文献   
16.
Antarctic krill, Euphausia superba, hatched from eggs and maintained for four years, were sampled periodically for age-pigment analysis. Extractable pigments from the eye and eyestalk ganglia were quantified using fluorescence intensity and standardised against protein. Three peak fluorescence intensities were detected at wavelengths of excitation 280 nm, emission 625 nm (pigment 1); excitation 355 nm, emission 510 nm (pigment 2); and excitation 463 nm, emission 620 nm (pigment 3). There was a positive correlation between the quantity of pigments 1 and 3 and the age of Antarctic krill. A model was developed to predict age from pigment 3 and to compare it with other age proxies (carapace length and eyeball diameter). The quantity of pigment 3 was the best predictor of age. The pigment method can discriminate between similar sized krill aged 12 and 36 months. Age pigments provide an improved tool for age estimation in Antarctic krill, particularly if used in conjunction with other demographic information.  相似文献   
17.
The structure of flame propagating through lycopodium dust clouds has been investigated experimentally. Upward propagating laminar flames in a vertical duct of 1800 mm height and 150×150 mm square cross-section are observed, and the leading flame front is also visualized using by a high-speed video camera. Although the dust concentration decreases slightly along the height of duct, the leading flame edge propagates upwards at a constant velocity. The maximum upward propagating velocity is 0.50 m/s at a dust concentration of 170 g/m3. Behind the upward propagating flame, some downward propagating flames are also observed. Despite the employment of nearly equal sized particles and its good dispersability and flowability, the reaction zone in lycopodium particles cloud shows the double flame structure in which isolated individual burning particles (0.5–1.0 mm in diameter) and the ball-shaped flames (2–4 mm in diameter; the combustion time of 4–6 ms) surrounding several particles are included. The ball-shaped flame appears as a faint flame in which several luminous spots are distributed, and then it turns into a luminous flame before disappearance. In order to distinguish these ball-shaped flames from others with some exceptions for merged flames, they are defined as independent flames in this study. The flame thickness in a lycopodium dust flame is observed to be 20 mm, about several orders of magnitude higher than that of a premixed gaseous flame. From the microscopic visualization, it was found that the flame front propagating through lycopodium particles is discontinuous and not smooth.  相似文献   
18.
Total diet study (TDS) samples of 14 food groups from 16 locations in Japan, collected in 1999 and 2000, were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) to estimate the update of daily intake of these contaminants from food. The mean daily intake of toxic equivalency (TEQ) for an adult weighing 50 kg, calculated at non-detected isomer concentrations equal to zero (ND=0), was estimated to be 2.25 pg TEQ/kg b.w./day. When non-detected isomer concentrations are assumed to be equal to half of the limits of detection (ND=1/2 LOD), the mean daily intake was estimated to be 3.22 pg TEQ/kg b.w./day. These values were below the tolerable daily intake (TDI) of 4 pg TEQ/kg b.w. for PCDD/Fs and dioxin-like PCBs set in Japan. In both the estimates, the mean daily intakes were highest from fish and shellfish (76.9% at ND=0 and 53.9% at ND=1/2 LOD of the total TEQs), followed by those from meat and eggs (15.5% at ND=0 and 11.7% at ND=1/2 LOD of the total TEQs). Congener specific data revealed that these total TEQ levels were dominated by 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and 3,3,4,4,5-PeCB in each case (71.7% at ND=0 and 63.1% at ND=1/2 LOD of the total TEQs). The dioxin-like PCBs (non-ortho and mono-ortho PCBs) accounted for about 50% of these total TEQs. These data will be very useful in the risk assessment of PCDD/Fs and dioxin-like PCBs from food in Japan.  相似文献   
19.
To study the volatilization and condensation behaviors of low-boiling-point elements in the waste melting process, experiments were conducted to collect the dust from a coke-type incineration residue melting furnace. Then, a comparison was made between the experimental results and the calculated values obtained from a thermodynamic equilibrium model in terms of the chemical composition of the dust. The composition of the dust collected from a cylindrical filter in the exhaust gas duct was determined by chemical methods, scanning electron microscopy/energy-dispersive X-ray spectroscopy, and X-ray analysis. As a result, the sampled dust was classified into two different types: fine particles mainly containing Na, K, Pb, and Zn collected from the side face of the cylindrical filter, and large particles containing Ca, Si, and Al collected from the bottom face of the cylindrical filter. From X-ray analysis of the sampled dust, NaCl, KCl, PbS, and ZnS were identified in the fine-particle dust, while CaO, SiO2, Al2O3 were detected in the large-particle dust. From the results of the thermodynamic equilibrium calculation in the gas cooling process from 2000 to 600 K, it was found that Na, K, Pb, and Zn volatilized as metals in the melting furnace were condensed as alkali chlorides such as NaCl and KCl and heavy metal sulfides such as PbS and ZnS. These computational results were in good agreement with the X-ray diffraction results of the sampled dust at a gas temperature of 823 K for the formation of NaCl, KCl, PbS, and ZnS.  相似文献   
20.
Combined ultrasonic (US) irradiation and sodium peroxodisulfate (Na2S2O8) treatment has been investigated for promotion of both decomposition of (4-chloro-2-methylphenoxy) acetic acid (MCPA) and mineralization of organic residues. This treatment is expected to accelerate both reactions, because the US cavitation effect promotes the production of radicals, such as SO 4 ? · and OH·, by the decomposition of Na2S2O8 and water. In this study, decomposition experiments were performed on 100?ppm MCPA aqueous solutions in a sonoreactor at reaction temperatures of 298?C333?K with US irradiation alone, Na2S2O8 treatment alone, and the combination of US and Na2S2O8 treatment. It was found that the combined treatment achieved a higher MCPA decomposition rate and total organic carbon (TOC) removal ratio than either treatment alone. The decomposition ratios of both MCPA and TOC increased with reaction temperature, and especially steep increases were observed at 333?K due to a significant promotion of thermal decomposition of Na2S2O8. The production of radical species was also promoted by the combined treatment. These results suggest that the higher MCPA decomposition rate and TOC removal ratio are due to the increased formation of sulfate and hydroxyl radicals via thermal and US decomposition of Na2S2O8.  相似文献   
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