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101.
This study is to modify the ecological footprint methodology by incorporating non-renewable or abiotic resources as an additional category. The use of abiotic resources can be quantified as global hectare by using thermodynamic approaches. A detailed case study on various countries including Australia, Belgium, Brazil, Canada, Japan, USA, and Vietnam shows the advantage of using the new modified ecological footprint (EF) as an indicator for sustainable development. The modified EF includes not only biotic resources, but also the abiotic resources. The case study indicates that the modified EF differs from the traditional EF up to 123% in the case of Belgium, and 90% in the case of Australia. For developing countries such as Brazil and Vietnam, the differences are relatively smaller (21% for Brazil and 9.4% for Vietnam). The estimated total ecological footprint of the world using the new method implies more serious problems associated with over consumption than using results from the original ecological footprint method.  相似文献   
102.
An estrogen receptor (ER)/androgen receptor (AR) ligand competitive binding assay (ER/AR-binding assay) and chemical analyses were used to evaluate the endocrine disrupting chemicals (EDCs) behavior of two municipal wastewater treatment plants (WWTPs) (K and S). In the influents, estrone (E1), androsterone (A), androstenedione (AD), BPA (bisphenol A), NP (nonylphenol) and daidzein (DZ) were detected in high amounts with subsequent 24 h-average concentrations of 350, 1000, 29, 1300, 3900, and 5700 ng/L in K-WWTP and of 310, 620, 59, 1600, 2600, and 8400 ng/L in S-WWTP. The estrogenic (androgenic) activity as 17 -estradiol (E2) equivalents (EEQ) or testosterone (Te) equivalents (TEQ) was consequently 620 ng E2/L (570 ng Te/L) and 580 ng E2/L (800 ng Te/L) for the two WWTPs. The removal e ciencies of the above mentioned sole target chemicals were 51%–100% for K-WWTP and 55.6%–100% for S-WWTP. The removal e ciencies of EEQ were about 73% for both WWTPs, while the removal e ciencies of TEQ were 62.1% for K-WWTP and 98.4% for S-WWTP. In addition, chemical-derived EEQ were about 1.2%–52.4% of those by ER-binding assay for K-WWTP and the corresponding ratios were 1.3%–83.3% for S-WWTP, while chemical derived TEQ were less than 3% of values measured by the AR-binding assay for both WWTPs.  相似文献   
103.
Cerumen, or propolis, is a mixture of plant resins enriched with bee secretions. In Australia, stingless bees are important pollinators that use cerumen for nest construction and possibly for colony’s health. While extensive research attests to the therapeutic properties of honeybee (Apis mellifera) propolis, the biological and medicinal properties of Australian stingless bee cerumen are largely unknown. In this study, the chemical and biological properties of polar extracts of cerumen from Tetragonula carbonaria in South East Queensland, Australia were investigated using gas chromatography-mass spectrometry (GC-MS) analyses and in vitro 5-lipoxygenase (5-LOX) cell-free assays. Extracts were tested against comparative (commercial tincture of A. mellifera propolis) and positive controls (Trolox and gallic acid). Distinct GC-MS fingerprints of a mixed diterpenic profile typical of native bee cerumen were obtained with pimaric acid (6.31 ± 0.97%, w/w), isopimaric acid (12.23 ± 3.03%, w/w), and gallic acid (5.79 ± 0.81%, w/w) tentatively identified as useful chemical markers. Characteristic flavonoids and prenylated phenolics found in honeybee propolis were absent. Cerumen extracts from T. carbonaria inhibited activity of 5-LOX, an enzyme known to catalyse production of proinflammatory mediators (IC50 19.97 ± 2.67 μg/ml, mean ± SEM, n = 4). Extracts had similar potency to Trolox (IC50 12.78 ± 1.82 μg/ml), but were less potent than honeybee propolis (IC50 5.90 ± 0.62 μg/ml) or gallic acid (IC50 5.62 ± 0.35 μg/ml, P < 0.001). These findings warrant further investigation of the ecological and medicinal properties of this stingless bee cerumen, which may herald a commercial potential for the Australian beekeeping industry.  相似文献   
104.
Hematocrit and hemoglobin concentration of yellowtail blood elevated more than 30% during severe hypoxia for 35 or 40 min. About 40% of the hematocrit elevation is considered to have been caused by erythrocyte supply from the spleen, and about 60% by hemoconcentration due to water shift out of the circulating plasma. Osmotic swelling of erythrocytes is considered not to have occurred, judging from the constant level in the saturation index of the blood.  相似文献   
105.
This paper presents the results from using a physical absorption process to absorb gaseous CO_2mixed with N_2using water by producing tiny bubbles via a liquid-film-forming device(LFFD)that improves the solubility of CO_2in water.The influence of various parameters—pressure,initial CO_2concentration,gas-to-liquid ratios,and temperature—on the CO_2removal efficiency and its absorption rate in water were investigated and estimated thoroughly by statistical polynomial models obtained by the utilization of the response surface method(RSM)with a central composite design(CCD).Based on the analysis,a high efficiency of CO_2capture can be reached in conditions such as low pressure,high CO_2concentration at the inlet,low gas/liquid ratio,and low temperature.For instance,the highest removal efficiency in the RSM–CCD experimental matrix of nearly 80%occurred for run number 20,which was conducted at 0.30 MPa,CO_2concentration of 35%,gas/liquid ratio of 0.71,and temperature of 15°C.Furthermore,the coefficients of determination,R~2,were 0.996 for the removal rate and 0.982 for the absorption rate,implying that the predicted values computed by the constructed models correlate strongly and fit well with the experimental values.The results obtained provide essential information for implementing this method properly and effectively and contribute a promising approach to the problem of CO_2capture in air pollution treatment.  相似文献   
106.
Butyltin (BT) and phenyltin (PT) compounds were measured in seawater, sediment, and biological samples collected from coastal areas of Otsuchi Bay, Japan. Tributyltin (TBT) compounds in seawater, sediment, plankton, mussels, scallops and fish were in the range of 0.008-0.074 microg liter(-1), 0.01-0.64 mg (kg dry wt)(-1), 0.24-9.8 mg (kg dry wt)(-1), 0.04-0.18 mg (kg wet wt)(-1), 0.10-0.13 mg (kg wet wt)(-1) and 0.01-0.02 mg (kg wet wt)(-1), respectively. Trace amount of PTs were found in seawater. The highest concentrations of TBT and triphenyltin (TPT) were found near a shipyard. Triorganotin compounds were more dominant than their metabolites. A positive correlation was observed between the concentrations of TBT and TPT in the mussels. Concentrations of TBT and TPT in mussels were high in the upper intertidal zone, and decreased toward the water.  相似文献   
107.
The fate of the giant jellyfish Nemopilema nomurai after death was examined in the southwest Sea of Japan. The density of dead jellyfish was greater than that of live animals. The dead animals are heavier than the Japan Sea Proper Water which occurs deeper than 200 m, suggesting that dead jellyfish sink to the sea floor. The sea floor survey, conducted with a towed video tape recorder (VTR) monitoring system between mid September and mid October, observed a total of 138 jellyfish during 28 of 29 operations. The density of carrion ranged between 0.2 and 5.1 individuals/1,000 m2 (mean ± SE = 1.1 ± 0.2). Ophiuroids occurred abundantly at 23 jellyfish carcasses and a sea anemone was observed attached to five carcasses. The VTR surveys confirmed that carrion sinks to the sea floor not only during the winter, the normal end of life for medusae, but also during the fall. A trap survey baited with medusae was also employed, and four different species were sampled with the traps: the snow crab (Chionoecetes opilio), a shrimp (Pandalopsis japonica), the ivory shell (Buccinum striatissimum) and an ophiuroid (Ophiura sarsii). Much of the trap bait remained (49–68% weight-mean = 60.3%) during the 23 h soak-time, and the reduction in weight was greater than that observed by bacterial decomposition, suggesting benthic animals consume dead organisms. The present study indicates that dead N. nomurai sink to the sea floor continuously and were subsequently consumed by benthic scavengers.  相似文献   
108.
Journal of Material Cycles and Waste Management - Shotcrete is a sprayed concrete placed on steep slopes that have been widely used because it can prevent surface weathering and erosion, and in...  相似文献   
109.
Livestock manure is suitable for use as a composting material. However, various intestinal microbes, such as Escherichia coli, are significant components of such manures. Thus, it is desirable that the level of intestinal microbes, and particularly opportunistic pathogens, in compost is inspected and counted regularly. The sensitivity and specificity of detection of E. coli in compost have been improved by selective cultivation followed by colony polymerase chain reaction (PCR) using the ECO primer. Indeed, the sensitivity of this method is higher than that of DNA extraction from compost and PCR. In this study, changes in numbers of E. coli present in a field-scale composting process over time was assessed using selective cultivation and colony PCR. Numbers of ECO-positive colonies after 24 h decreased, with a concomitant rise in compost temperature. ECO-positive colonies were not detected from 33 to 48 h. However, ECO-positive colony numbers increased beginning on day 4 and continuing until day 42. Thus, it seems likely that the high temperatures reached during the composting process did not affect E. coli numbers in the final compost. Additionally, selective cultivation followed by colony PCR using specific primers is an appropriate method of determining levels of cultivable pathogens in composted materials.  相似文献   
110.
Background, aim, and scope  The first step in the restoration of a medieval stained glass window is the evaluation of its degree of degradation. This implies the study of the chemical composition of the stained glass as well as the new mineral phases developed on its surface (patinas). Patinas are clearly related to glass composition, time, environmental conditions, microenvironments developed in local zones, bioactivity, physical and chemical factors, etc. This study was carried out on patinas developed in selected Na-rich stained glass of the Santa Maria de Pedralbes Monastery (Barcelona, Spain). The location of this monument in the city (about 5 km from the shoreline and close to the Collserola hill flank) helped to determine the environmental conditions in which patinas developed. The aim of our study was to characterize the patinas formed on the surface of the selected glass of this monastery in order to understand the role of the chemical composition of the original glass (Na-rich) as well as the environmental conditions in which they developed. Materials and methods  Powdered samples of two different color-type patinas (ochre-orange and brownish) were collected in the external and internal parts of the stained glass windows of the Prebystery and Chapter House of the Pedralbes Monastery by using a precision (odontological) drill. These patinas were subsequently analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Results  XRD analyses evidenced the presence of sulfates (gypsum and thenardite), calcite, Ca-oxalates (whewellite and weddellite), and quartz forming part of the patinas. Although these mineral phases can be found in both color-type patinas, whewellite and thenardite are more common in the ochre-orange patinas. The results obtained were validated by the FTIR measurements. It has been observed, when thenardite is present, that gypsum occurs as traces. Thenardite is in most of the cases associated with whewellite and mainly occurs in the internal parts of the glass. In contrast, weddellite is limited to the absence of thenardite and whewellite and to the external parts of the stained glass. Quartz is present in all the patinas independent of their location and color. Calcite also occurs in many samples. It appears in both color-type patinas and, in some cases, is associated to the presence of weddellite but not to whewellite and/or thenardite. Discussion  Glass composition together with environmental conditions and location of the patinas (internal or external parts of the stained glass window), as well as the provenance of the glass within the monastery, are the main factors that define the development of the new mineral phases. Moreover, the action of microorganisms, when present, can also strongly influence the development of some mineral phases. For example, the formation of calcite in the external parts of the stained glass (associated with the presence of oxalates) is related to the action of microorganisms. When calcite is formed in the internal parts of the glass and it is not associated with the presence of Ca-oxalates, an inorganic origin can be invoked. The presence of weddellite requires a very humid microenvironment with very little exposure to sunlight. In fact, this mineral phase has only been observed in the external parts of some glass located in the humid and shady side of the monastery. Whewellite (which only appears in the internal parts) needs a low degree of relative humidity. It has been observed that sulfur precipitating in basically one mineral phase (thenardite or gypsum) depends on the microenvironmental conditions of the moment and the glass composition. When thenardite occurs, it can be maintained that the original glass is of Na composition. The occurrence of quartz in all samples is interpreted as being due to the deposition of atmospheric particulate matter. The color of the patinas can be originated by different processes (presence of carotenes, organic pigmentation, atmospheric contamination, etc.). Conclusions  In the case of moderately weathered stained glass windows, the combination of XRD and FTIR techniques is very useful to obtain a fast preliminary evaluation of the degree of weathering of a stained glass window. The presence of specific mineral phases in the patina (e.g., thenardite) confirms the Na composition of the original stained glass. This is important since Na-rich glass underwent a lesser degree of weathering than K- or K-Ca-rich glass. However, their absence cannot preclude other possibilities. It has been extensively evidenced through time that environmental conditions play an important role on the formation of the different mineral phases which form part of the patinas. Recommendations and perspectives  The first step in the restoration of a stained glass window is the evaluation of the degree of deterioration of the glass. This evaluation includes a chemical analysis of the glass as well as a characterization of the patinas developed on their surfaces. The obtained results will be essential in order to define the best restoration practices to be followed.  相似文献   
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