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1.
A novel source of biofertilizer from feather biomass for banana cultivation   总被引:1,自引:0,他引:1  
Feather waste is a promising protein biomass available as by-product from poultry processing was found to be rich in peptides, amino acids, and minerals like nitrogen, phosphorus, potassium, calcium, magnesium, iron, manganese, zinc, and copper. Soil and foliar application of these products, besides representing a sustainable solution to the problem of feather disposal, may also represent an effective strategy to tackle the environmental effluence. As a consequence, they were also found to be very attractive in elevating the protein, amino acids, reducing sugar, total chlorophyll, and proline content of plants. On the other side, fertilizing effect enhanced the antioxidant potential of banana fruit which was assessed using 2, 2-diphenyl-1-picrylhydrazyl, ferric reducing/antioxidant power, and N, N-dimethyl-p-phenylendiamine. This was associated with considerably higher antioxidant contents like total phenolics and flavonoids. Therefore, the application of this organic amendment could promote and improve the agro-ecosystem, human health; soil biological activities, and at the same time enhance the production of plant or products rich in bioactive substances.  相似文献   

2.

Introduction  

Naturally occurring hydroxylated polybrominated diphenyl ethers (OH-PBDEs), their methoxylated counterparts (MeO-PBDEs), and polybrominated dibenzo-p-dioxins (PBDDs), together with their potential precursors polybrominated phenols (PBPs) and polybrominated anisoles (PBAs), were analyzed in blue mussels (Mytilus edulis) gathered along the east coast (bordering the Baltic Sea) and west coast of Sweden (bordering the North Sea). Brown algae (Dictyosiphon foenicolaceus) and cyanobacteria (Nodularia spumigena) from the Baltic Sea, considered to be among the primary producers of these compounds, were also analyzed for comparison.  相似文献   

3.
Pan J  Yang YL  Chen DZ  Xu Q  Tang H  Li Y  Nie LM  Jiang K  Xi DL 《Chemosphere》2008,70(9):1699-1706
Seven of surface sediments, one sediment core and two mussel samples were collected from the Qingdao coastal sea of the western Yellow Sea and analyzed to determine the horizontal distribution, deposition flux, and toxicity equivalency (TEQs) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The total PCDD/Fs concentrations in the surface sediments ranged between 10.7 and 428 ng kg(-1) dry wt. The horizontal distribution of PCDD/F congeners in the sediments was characterized by elevated concentrations at the locations in the east of Jiaozhou Bay with the highest concentration occurring near the Haibo River mouth. Physical parameters (total organic carbon contents and sediment types) and the current circulation systems in Jiaozhou Bay can be important factors controlling the horizontal distribution pattern of PCDD/Fs in the bay. The influence of the Haibo River as a source of pollution was evidenced by PCDD/F homologue profiles, indicating a contribution from sewage sludge in addition to other possible sources. Records from the sediment core revealed that the total PCDD/Fs in the Qingdao coastal sea were nearly constant since 1951 till 1980s and increased remarkably after 1980s. The total 2,3,7,8-substituted PCDD/Fs and total TEQs of PCDD/Fs on the lipid basis in the mussel sample inside the bay were significantly higher than in the adjacent sediment. The homologue profiles of PCDD/Fs in the mussels were quite different from those of the sediments, characterized by high TCDF (50% of the total PCDD/Fs).  相似文献   

4.
Bange HW  Uher G 《Chemosphere》2005,58(2):177-183
We conducted irradiation experiments with riverine, estuarine, and marine water samples to investigate the possibility of photochemical methane (CH4) formation. CH4 photoproduction was undetectable under oxic conditions or in the absence of methyl radical precursors indicating that its photochemical formation is negligible in the present ocean. Significant photochemical CH4 production was observed in the presence of a methyl radical precursor such as acetone under strictly anoxic conditions. Our results indicate an indirect formation mechanism with coloured dissolved organic matter acting as photosensitizer. We suggest that photochemical CH4 formation might have occurred in the anoxic ocean surface layer of the Archean prior to the onset of O2 accumulation in the atmosphere at around 2300 million years ago. Oceanic CH4 photoproduction via methyl radical (CH3) precursors and its subsequent release to the atmosphere may have contributed to high CH4 mixing ratios in the Archean atmosphere.  相似文献   

5.
To investigate the kinetics of PCBs and dioxins, 3 week old broilers and 3 month old pigs were fed with a 10-fold diluted feed from the Belgium crisis for one week, followed by a period on clean feed. In the case of broilers this resulted in levels for dioxins, non-ortho and mono-ortho PCBs in fat of 102, 84 and 216 ng TEQ/kg, summarized to 402 ng TEQ/kg. Total levels decreased to 217 and 109 ng TEQ/kg after 1 and 3 weeks on clean feed. Indicator PCB levels decreased from an initial 6.2 mg/kg fat to respectively 3.2 and 1.5 mg/kg. The ratio of indicator PCBs to dioxins TEQs was stable over this period. Levels in back fat of pigs at the end of the exposure period were 26, 15, 82 and 123 ng TEQ/kg for respectively dioxins, non-ortho PCBs, mono-ortho PCBs and the sum. Total TEQ levels decreased to respectively 95, 70, 40, 22 and 12 ng TEQ/kg after 1, 2, 4, 8 or 12 weeks on clean feed. After 12 weeks dioxin levels were around 1 ng TEQ/kg. Indicator PCB levels decreased from 3.48 mg/kg to 2.65, 2.01, 1.25, 0.76 and 0.45 mg/kg fat, again after 1, 2, 4, 8 or 12 weeks on clean feed. Levels of dioxins decreased more rapidly than those of indicator PCBs, also reflected by the ratio of indicator PCBs to dioxins, being 133,000 at the end of the exposure period and 357,000 after week 12. It is concluded that the use of indicator PCBs for dioxins, in the case of a combined exposure, is a safe alternative for screening and in the case of pigs results in an overestimation rather than underestimation of the dioxin levels.  相似文献   

6.
The economy of an industrialized country is greatly dependent on fossil fuels. However, these nonrenewable sources of energy are nearing the brink of extinction. Moreover, the reliance on these fuels has led to increased levels of pollution which have caused serious adverse impacts on the environment. Hydrogen has emerged as a promising alternative since it does not produce CO2 during combustion and also has the highest calorific value. The biohythane process comprises of biohydrogen production followed by biomethanation. Biological H2 production has an edge over its chemical counterpart mainly because it is environmentally benign. Maximization of gaseous energy recovery could be achieved by integrating dark fermentative hydrogen production followed by biomethanation. Intensive research work has already been carried out on the advancement of biohydrogen production processes, such as the development of suitable microbial consortium (mesophiles or thermophiles), genetically modified microorganism, improvement of the reactor designs, use of different solid matrices for the immobilization of whole cells, and development of two-stage process for higher rate of H2 production. Scale-up studies of the dark fermentation process was successfully carried out in 20- and 800-L reactors. However, the total gaseous energy recovery for two stage process was found to be 53.6 %. From single-stage H2 production, gaseous energy recovery was only 28 %. Thus, two-stage systems not only help in improving gaseous energy recovery but also can make biohythane (mixture of H2 and CH4) concept commercially feasible.  相似文献   

7.
Persistent aromatic bromine, chlorine and mixed chlorine-bromine compounds were analysed from recycled aluminium smelter (ALS) ashes to explore the impact of brominated flame retardants (BFR) on their formation. Polybrominated diphenyl ethers (PBDE) were the most abundant original BFRs found. Induction furnace ash contained tetra- to octa-BDEs about 2000ng g(-1) in similar congener ratios as the original scrap, but contents of nona- and deca-BDEs were only 25 and 5ng g(-1) indicating their significant degradation in ALS process. In the most non-polar fraction, PCB levels and profiles were similar as earlier ALS ash samples in 1990s. The highest PCB level measured was that of deca-CB (450ng g(-1)) in the induction furnace ash. In this fraction, bromo compounds were non-detectable (<5ng g(-1)). Fraction of the most polar compounds (from reversed toluene elution of carbon column ("dioxin fraction") contained PCDDs, PCDFs and polychlorinated dibenzothiophenes (PCDTs) in similar amounts and congener profiles as earlier investigated ALS ash samples. Bromine-containing dioxin and furan congeners were not detected. From individual PCDDs and PCDFs, octaCDF was the most abundant (205ng g(-1)) in induction furnace ash. In this fraction, the original BFR, tetrabromo-bisphenol-A, was identified. Its level in the induction furnace ash was approximated to be 388ng g(-1). In addition, 12 novel brominated and chlorinated compounds were found as abundant (8-441ng g(-1) in the induction furnace ash) contaminants from the fraction. Four of them were bisphenol derivatives, five biphenylols, then octachlorofluorenone (OCFL) and octachlorobiphenylene (OCBP). Their structures or structure types were deduced from total low-resolution EI mass spectra by theoretical isotope cluster simulation (ICLU) and through known fragmentation rules.  相似文献   

8.
9.
In FRG and other countries unequivocal criteria for the limitation of dioxins (PCDD's/PCDF's) in food like vegetables and fruits are lacking. These have to be directly associated with the limitation of dioxins in the soil and the deposition of particulate matter as the two main pathways for plant contamination. Based on recent investigations in the vicinity of cable-waste incinerators in Northrhine-Westphalia with comparatively high contents of dioxins in garden plants and soils and other sources of dioxins, considerations are given for the establishment of the criteria urgently needed.  相似文献   

10.
11.
The issues of energy security, dwindling supply and inflating price of fossil fuel have shifted the global focus towards fuel of renewable origin. Biodiesel, having renewable origin, has exhibited great potential as substitute for fossil fuels. The most common route of biodiesel production is through transesterification of vegetable oil in presence of homogeneous acid or base or solid oxide catalyst. But, the economics of biodiesel is not competitive with respect to fossil fuel due to high cost of production. The vegetable oil waste is a potential alternative for biodiesel production, particularly when disposal of used vegetable oil has been restricted in several countries. The present study evaluates the efficacy of a low-cost solid oxide catalyst derived from eggshell (a food waste) in transesterification of vegetable oil and simulated waste vegetable oil (SWVO). The impact of thermal treatment of vegetable oil (to simulate frying operation) on transesterification using eggshell-derived solid oxide catalyst (ESSO catalyst) was also evaluated along with the effect of varying reaction parameters. The study reported that around 90 % biodiesel yield was obtained with vegetable oil at methanol/oil molar ratio of 18:1 in 3 h reaction time using 10 % ESSO catalyst. The biodiesel produced with ESSO catalyst from SWVO, thermally treated at 150 °C for 24 h, was found to conform with the biodiesel standard, but the yield was 5 % lower compared to that of the untreated oil. The utilization of waste vegetable oil along with waste eggshell as catalyst is significant for improving the overall economics of the biodiesel in the current market. The utilization of waste for societal benefit with the essence of sustainable development is the novelty of this work.  相似文献   

12.
Yasuhara A  Katami T  Shibamoto T 《Chemosphere》2006,62(11):1899-1906
Polyvinylidene chloride (PVDC; polymer of 1,1-dichloroethylene) was combusted with paper in a well-controlled, small-scale incinerator at an average grate temperature of 700 °C, and then dioxins (PCDDs, PCDFs, and coplanar-PCBs) formed in the exhaust gases were analyzed by gas chromatography/mass spectrometry. PVDC lowered the combustion temperature due to its less flammable character. The amount of total dioxins (PCDDs + PCDFs + coplanar-PCBs) formed in the exhaust gas was 58.0 ng/g of a combustion sample and its toxicity equivalency quantity (TEQ) value was 0.64 ng-TEQ/g. The amount of PCDDs formed in the sample ranged from 2.33 ng/g (Cl8-isomer) to 0.048 ng/g (Cl1-isomer). The lower the number of chloride, the less production of PCDDs. On the other hand, there was no relation between the number of chloride and PCDF formation. The amount of PCDFs formed in the sample ranged from 8.02 ng/g (Cl2-isomer) to 4.46 ng/g (Cl8-isomer). A polyvinylchloride (PVC) sample produced 207 ng/g of total dioxins and a PVDC sample produced 57.4 ng/g of total dioxins when they were combusted under the same conditions. An approximately equal composition of dioxin isomers was formed from PVDC and PVC samples. Paper was found to contribute to PCDF formation when it was combusted with plastics.  相似文献   

13.
A survey of drinking water supplies in the Province of Ontario was initiated in 1983 to determine the extent of their contamination by polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). This drinking water survey arose from concerns regarding the discovery of PCDDs and PCDFs in sport fish from western Lake Ontario in the early 1980's.A total of 49 water supplies throughout all Regions of Ontario have been examined to date. Water supplies in the vicinity of chemical industries and pulp and paper mills were sampled more frequently; as many as 20 times. Detection limits were in the low parts per quadrillion (ppq) range for all tetra- to octachlorinated PCDDs and PCDFs.As of February 1989, 4, 347 results were received for 399 raw and treated water samples. Only 37 positive results were reported, constituting less than 1 percent of the total number of results. The O8CDD congener accounted for 36 of the 37 positive results. The 2,3,7,8- TCDD isomer was not detected in any sample.  相似文献   

14.
Novel evidence for natural formation of dioxins in ball clay   总被引:2,自引:0,他引:2  
Elevated concentrations of dioxins in ancient ball clay from the Mississippi Embayment suggest natural formation of dioxins in the environment. Evidence for such natural formation in ball clay derives from unique congener profiles in undisturbed ancient clay deposits and from the lack of other anthropogenic contaminants. Here we present novel evidence of natural formation of dioxins based on congener-specific carbon isotopic analysis of octachlorodibenzo-p-dioxin (OCDD) in ball clays from the USA and Japan. The analyses were performed using a combination of double-column high performance liquid chromatography clean-up and two-dimensional gas chromatography-isotope ratio mass spectrometry. Elevated concentrations of OCDD found in ball clays from the USA and Japan were isotopically distinguished from the anthropogenic source materials (fly ash and pentachlorophenol) and environmental samples (sediment and soil). The isotopic signatures and the occurrence of OCDD in ancient ball clays deposited in the Tertiary Era provide evidence for the in situ formation of dioxins.  相似文献   

15.
Human milk survey for dioxins in the general population in Japan   总被引:1,自引:0,他引:1  
Uehara R  Peng G  Nakamura Y  Matsuura N  Kondo N  Tada H 《Chemosphere》2006,62(7):1135-1141
BACKGROUND: Much attention has been paid to the level of dioxins in breast milk in Japan but few large-scale studies have been conducted on the subject. METHODS: From 1997 to 2002, we collected 839 samples of breast milk from primiparas residing throughout Japan. Starting in 1999, breast milk was also collected from secundiparas. Seven isomers of polychlorinated dibenzo-p-dioxins (PCDDs), 10 of polychlorinated dibenzofurans (PCDFs), 4 of coplanar polychlorinated biphenyls (Co-PCBs) and 8 of mono-orthochlorinated polychlorinated biphenyls (mono-ortho PCBs) were analyzed by employing gas chromatography and mass spectrometry. A correlation between the level of dioxins in human milk and the age of the mothers was noted for the primiparas and the secundiparas; and the levels were compared between the first and the second deliveries. Grouped by parity and prefecture in each year, observations were also made on the trends in these levels. Dioxin levels are shown by using geometric means because their distributions were skewed to the left. RESULTS: The sum of PCDDs and PCDFs, Co-PCBs, mono-ortho PCBs, and total dioxins in the breast milk of primiparas were 13.9, 5.4, 3.4, and 22.7 pg TEQ/g fat, respectively. In the samples obtained from secundiparas, these levels were 63-68 percents of those taken from the primiparas. The correlation coefficients between the PCDDs/DFs, Co-PCBs, mono-ortho PCBs, and total dioxins and the age of the primiparas were 0.19, 0.17, 0.36, and 0.24, respectively. All these correlations were statistically significant (p < 0.001). The positive correlations between these contaminants and the age of the secundiparas were also examined. The total dioxins as well as PCDDs/DFs, Co-PCBs, and mono-ortho PCBs in the breast milk of the primiparas declined significantly between 1998 and 2002 (regression coefficients: -0.04, -0.05, -0.03, and -0.03, respectively). However, no significant decline in these levels was observed when sorted by prefectures. CONCLUSIONS: Much attention should be paid to the age and parity of nursing mothers when investigating the relationship between the level of dioxins in breast milk and the body burden of infants.  相似文献   

16.
采用稀释共沉淀法制备了Mg O-Zr O2固体碱催化剂,通过催化预处理低酸值油的酯交换反应来制备生物柴油。采用BET、SEM、XRD等方法对催化剂进行表征。主要研究了固体碱制备中Mg O-Zr O2物料比和煅烧温度对催化剂催化活性的影响,通过对比发现:制备的催化剂孔径均在2~10 nm之间,Zr O2以单斜晶相微晶形式存在并很好地分散于Mg O相中,表现出较高的催化活性。当固体碱中Mg/Zr物料比为3∶1,煅烧温度为500℃时催化剂的活性最佳,通过对酯交换反应影响因素的考察得到了催化反应的最佳工艺条件;酯交换率达到96.9%。  相似文献   

17.
The aim of this study was to highlight the potential use of recycled wool-based nonwoven material for the removal of diesel fuel, crude, base, vegetable and motor oil from water. Sorption capacity of the material in water and in oil without water, oil retention, sorbent reusability and buoyancy in static and dynamic conditions were investigated. The results show high sorption capacity of recycled wool for different kinds of oil. This sorbent also exhibited excellent buoyancy after 24h of sorption as well as a good reusability since the decrease in sorption capacity did not exceed 50% of the initial value after five sorption cycles in oil without water.  相似文献   

18.
19.
Expanded, 45 reaction, and core, 12 reaction, kinetic models have been developed that account for the major features in the homogeneous formation of polychlorinated dibenzo-p-dioxins (PCDD) from the oxidation of 2,4,6-trichlorophenol (P). The expanded and core schemes provide good agreement between experimental and calculated yields of PCDDs using the CHEMKIN combustion package or the React kinetic program, respectively. Steady-state approximations of the reaction kinetic models including radical-molecule and radical-radical formation pathways of PCDD, as well as oxidative destruction pathways of chlorinated phenoxyl radicals, reveal a competition between reactions of chlorinated phenoxyl radicals with chlorinated phenols, recombination reactions of chlorinated phenoxyl mesomers, and destruction/decomposition of phenoxyl radicals.  相似文献   

20.
Food is considered to be the main source of dioxins (PCDDs) and dibenzofurans (PCDFs) for human intake, but there are relatively few publications reporting the levels of dioxins and furans in food samples.(1–4) Food samples from western to eastern Russia were collected during three recent trips by one of us (AS), and tested for dioxins and dibenzofurans to provide some indication of environmental contamination. The results show that in specific food samples there are more dioxins present than dibenzofurans, but in fish samples the opposite is true. We compare the levels found in Russian food with levels found in samples from other countries, on both wet weight and lipid basis. These Russian samples show ranges similar to but slightly lower than those seen in other industrial countries.  相似文献   

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