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131.
Olga Filippova  Ilan Noy 《Disasters》2020,44(1):179-204
New Zealand introduced a seismic retrofitting policy in the wake of the catastrophic Canterbury earthquakes of 2010–11. The aim was to enforce seismic strengthening of earthquake-prone commercial buildings throughout the country. This study focuses on regional urban centres and the economic obstacles to strengthening their aging building stock. In investigating one town, Whanganui, we describe conditions, analyse cases, and identify incentives that apply equally to many other towns in New Zealand. We argue that incentives that suit high-growth, high-value major urban centres are a poor fit for the periphery. Around the world, many places need to upgrade their privately-owned building stock to protect it from disasters, while governments face similar challenges as they struggle to initiate the strengthening of commercial buildings. We analyse the current incentive schemes that aim to support the achievement of policy goals and suggest alternative incentive schemes that can be implemented to improve strengthening outcomes.  相似文献   
132.
Regional Environmental Change - Agroecosystems are facing a global challenge amidst a socioecological transition that places them in a dilemma between increasing land-use intensity to meet the...  相似文献   
133.
Environmental lead poses a serious threat for public health, particularly, for children. The use of substances with metal-binding properties, such as natural alginates, may be a potentially effective method for elimination of toxic metal ions from human body. In present study, effect of calcium alginate isolated from brown algae on distribution of the lead ions in preschool children was investigated. In the beginning of the study, lead concentration in urine, feces, and hair was determined. Then these children were administered a dietary supplement containing calcium alginate for four weeks. The results showed that all children participated in the study had a high baseline median lead level in urine (1.1 µg/L), feces (4.6 µg/g), and hair (5.0 µg/g). Administration of calcium alginate resulted in twofold increase of the urine lead level within two weeks from the start of the treatment. At the end of alginate administration, significant decrease of lead concentration in hair was registered. These results suggest that calcium alginate can potentially prevent accumulation of the lead ions in the body and may be used as an active agent for elimination of this toxic metal from human body.  相似文献   
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135.
A novel visible light-active photocatalyst formulation(NdT/OP) was obtained by supporting N-doped TiO_2(NdT) particles on up-conversion luminescent organic phosphors(OP). The photocatalytic activity of such catalysts was evaluated for the mineralization process of spiramycin in aqueous solution. The effect of NdT loading in the range 15–60 wt.% on bulk and surface characteristics of NdT/OP catalysts was investigated by several chemicophysical characterization techniques. The photocatalytic performance of NdT/OP catalysts in the removal of spyramicin from aqueous solution was assessed through photocatalytic tests under visible light irradiation. Total organic carbon(TOC) of aqueous solution,and CO and CO_2 gas concentrations evolved during the photodegradation were analyzed. A dramatic enhancement of photocatalytic activity of the photostructured visible active NdT/OP catalysts,compared to NdT catalyst,was observed. Only CO_2 was detected in gas-phase during visible light irradiation,proving that the photocatalytic process is effective in the mineralization of spiramycin,reaching very high values of TOC removal. The photocatalyst NdT/OP at 30 wt.% of NdT loading showed the highest photocatalytic activity(58%of TOC removed after 180 min irradiation against only 31% removal after 300 min of irradiation of NdT). We attribute this enhanced activity to the high effectiveness in the utilization of visible light through improved light harvesting and exploiting. OP particles act as "photoactive support",able to be excited by the external visible light irradiation,and reissue luminescence of wavelength suitable to promote NdT photomineralization activity.  相似文献   
136.
Composition of exhaust from a ship diesel engine using heavy fuel oil (HFO) was investigated onboard a large cargo vessel. The emitted particulate matter (PM) properties related to environmental and health impacts were investigated along with composition of the gas-phase emissions. Mass, size distribution, chemical composition and microphysical structure of the PM were investigated. The emission factor for PM was 5.3 g (kg fuel)?1. The mass size distribution showed a bimodal shape with two maxima: one in the accumulation mode with mean particle diameter DP around 0.5 μm and one in the coarse mode at DP around 7 μm. The PM composition was dominated by organic carbon (OC), ash and sulphate while the elemental carbon (EC) composed only a few percent of the total PM. Increase of the PM in exhaust upon cooling was associated with increase of OC and sulphate. Laser analysis of the adsorbed phase in the cooled exhaust showed presence of a rich mixture of polycyclic aromatic hydrocarbon (PAH) species with molecular mass 178–300 amu while PM collected in the hot exhaust showed only four PAH masses.Microstructure and elemental analysis of ship combustion residuals indicate three distinct morphological structures with different chemical composition: soot aggregates, significantly metal polluted; char particles, clean or containing minerals; mineral and/or ash particles. Additionally, organic carbon particles of unburned fuel or/and lubricating oil origin were observed. Hazardous constituents from the combustion of heavy fuel oil such as transitional and alkali earth metals (V, Ni, Ca, Fe) were observed in the PM samples.Measurements of gaseous composition in the exhaust of this particular ship showed emission factors that are on the low side of the interval of global emission factors published in literature for NOx, hydrocarbons (HC) and CO.  相似文献   
137.
Dichomitus squalens efficiently decolorized both Orange G and Remazol Brilliant Blue R (RBBR) at concentrations of 0.5gl(-1) and 3gl(-1) in static and shaken culture and also on solid medium within 14d. The presence of the dyes in the culture medium mostly caused a decrease in biomass production and in growth rate, which was more significant in the case of RBBR. After 14d of cultivation, electron microscopy showed substantial morphological changes in mycelia of D. squalens growing in media containing dyes. The hyphae deformations were more intensively manifested in solid media than in liquid culture. In all the cases, the morphological changes were more prominent in the presence of RBBR. Higher concentrations of both dyes brought about more intensive changes. The toxicity of synthetic dyes Orange G and RBBR was tested using a bioassay based on the growth inhibition of duckweed Lemna minor. Two endpoints such as the number of fronds and their weight were studied during the bioassay. The results showed higher toxicity of RBBR than that of Orange G. The toxicity of both dyes decreased after the decolorization process.  相似文献   
138.
The historical floods that have occurred since the seventeenth century were collected for a study area in southern Italy. Damages caused by floods, rainfall and the main anthropogenic modifications are discussed all together. The aim was to assess whether the frequency of floods is changing and, if so, whether these changes can be attributed to either rainfall and/or anthropogenic modifications. In 4?% of cases, mainly occurred in past centuries, floods damaged people. Hydraulic works, roads and private buildings were the more frequently damaged elements (25, 18 and 14?% of the cases, respectively). The annual variability of rainfall was discussed using an annual index. Short duration-high intensity rainfalls were characterized considering time series of annual maxima of 1, 3, 6, 12, and 24?h and daily rainfall. The rainfall shows a decreasing trend, in terms of both the annual maximum of short duration and the annual amount. The population has been progressively increasing since the sixteenth century, except during the years following the catastrophic 1908 earthquake. The rate of population growth has been very high since the second half of the twentieth century; the urbanized areas greatly increased, especially following the second half of the twentieth century. At the same time, the trend of damaging floods has been increasing, especially since the seventies. The analysis indicates that, despite a rainfall trend favourable towards a reduction in flood occurrence, floods damage has not decreased. This seems to be mainly the effect of mismanagement of land use modifications.  相似文献   
139.
The paper studies changes in the content and composition of lipids in the membranes of chloroplasts, mitochondria and microsomes of the aquatic plant Hydrilla verticillata exposed to copper ions (100 μM; 1, 3, 6 and 24 h). The rate of copper accumulation and the coefficient of its extraction by the plant were also determined. The presence of copper in the incubation medium and its accumulation in the plant tissues decreased the content of photosynthetic pigments, stimulated lipid peroxidation and enhanced membrane permeability. The gradual accumulation of copper in the plant tissues was accompanied by specific changes in the composition of lipids: the content of sulfolipids (SQDG) in chloroplasts declined; the content of monogalactosyl diacylglycerols (MGDG), digalactosyl diacylglycerols (DGDG) and phosphatidyl glycerols (PG) in chloroplasts and mitochondria grew after an hour of copper exposure; and the content of all the lipids except phosphatidic acids (PA) decreased after 3 h of exposure. The decline in the content of phosphatidyl cholines (PC) was first observed in the membranes of microsomes (after an hour of exposure) and later in the membranes of chloroplasts and mitochondria (after 3-6 h of exposure). The experiments with incorporation of [2-14C]sodium acetate into fatty acids of polar lipids showed that in parallel with lipid destruction, there took place an intensive and specific renewal of the lipid pool of subcellular membrane fractions.  相似文献   
140.
The aim of this study was to develop a method based on ultra high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS) for lipid profiling in human placental choriocarcinoma (JEG-3) cells. Lipids were solid–liquid extracted from JEG-3 cells using a solution of chloroform/methanol (2:1, v/v) in a simple procedure requiring minimal sample alteration. Simultaneous separation of complex lipid mixtures in their major classes was achieved with a reversed-phase (C8) UHPLC column and a mobile phase containing methanol with 1 mM ammonium formate and 0.2 % formic acid (A)/water with 2 mM ammonium formate and 0.2 % formic acid (B). Lipids were characterized using time-of-flight (TOF) and Orbitrap under full scan and positive electrospray ionization mode with both analyzers. A total of 178 species of lipids, including 37 phosphatidylcholines (PC), 32 plasmalogen PC, 9 lyso PC, 4 lyso plasmalogen PC, 30 triacylglycerols, 22 diacylglycerols, 7 cholesterol esters, 25 phosphatidylethanolamines, and 12 sphingomyelins, were identified using TOF and Orbitrap. The identification of all lipid classes was based on exact mass characterization with an error < 5 ppm. The developed methodology was applied to study lipid alterations in human placental cells against the exposure to perfluorinated chemicals (PFCs) and tributyltin (TBT).  相似文献   
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