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1.
英国位列欧洲糖果制造业(含谷物棒产品)之首,同时也是巧克力消费的第一大国.来自Datamonitor的数据表明,尽管英国有这么好的市场,其在2001年时巧克力工业也经历了衰退,仅实现产值55.10亿美元,但在之后的几年中形式略有好转,预计到2006年增幅将达到9.5%.这就是说,每年将以2.3%的速度增长并最终达到61.79亿美元.  相似文献   

2.
Abstract

Periwinkle is a potential source of good‐quality proteins. It contains most of the essential amino acids in adequate amount for human nutrition. The shellfish is capable of accumulating toxigenic microorganisms as well as toxic heavy metals if harvested from polluted water. Harvesting and processing are still mainly at artisanal levels—for example, in West Africa due to the clumsy methods of harvesting and removal of the meat from the shells. There is need for strict environmental control of the harvest areas and adequate processing of these marine animals in order to ensure safety and wider distribution of the product.  相似文献   

3.
Livestock keeping constitutes a traditional and important economic activity in the Arab region. This paper aims to assess the role of the Arab livestock sector in food and nutritional security in terms of demand, supply, national policies and trade in the light of major environmental constraints, with data illustrations from Morocco (Mediterranean country) and Saudi Arabia (oil-rich country). Demand for livestock products is increasing in the Arab region driven by the growing population with different degrees of increased urbanization and wealth. On the supply side, local livestock production is largely based on rainfed mixed and pastoral livestock systems making it vulnerable to the effects of climate change and water scarcity. Intensive systems, where present, are mostly dependent on feed imports with an important water footprint. Livestock production is further conditioned by a history of arbitrary national policies that had a particularly negative effect on small producers and contributed to the degradation of national resources. Arab countries rely on trade from the world market to fill their gap in animal feed and livestock products with varying trading power based on wealth and the availability of free trade agreements. Following analysis of the sector, the paper concludes with the proposition of a pro-poor policy framework for the development of a sustainable Arab livestock sector.  相似文献   

4.
5.
6.
ABSTRACT

A new and rapid dispersive solid phase extraction method by using a green-synthesised UiO-66(Zr)-(COOH)2 (Zr-BTeC) adsorbent with body-centred cubic (bcu) topology was developed for determination of tartrazine in food samples. Zr-BTeC was used for the first time as an adsorbent for tartrazine. It was synthesised and characterised by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, Brunauer–Emmett–Teller surface area analysis, and zeta potential measurements. Tartrazine was determined at 405 nm spectrophotometrically. Experimental conditions were optimised in order to achieve quantitative recoveries. The sample acidity was found to be 0.02 mol L?1 HCl. The amount of Zr-BTeC was 10 mg. Both adsorption and elution contact times were only 5 s without the need for vortexing. Elution was with 2 mL of 0.5 mol L?1 NH3. A sample volume of 45 mL was selected as optimum. The adsorption capacity for tartrazine with Zr-BTeC was found to be 185 mg g?1 and the adsorbent was reusable up to 40 cycles. The tartrazine concentrations found by the developed method in food supplements were compared with the results obtained by HPLC method for the same samples. Statistical analysis results showed that there are insignificant differences between the results of the two methods (p = .05). The method was successfully applied to the determination of tartrazine in spiked chewing gums, lemon flavoured icing glaze, and jelly samples.  相似文献   

7.
Traditional pollution control technologies are able to capture oxidized forms of mercury to some extent; however, they show low efficiency for the control of elemental mercury emissions. This study developed a novel mercury removal technology: injection of sodium tetrasulfide (Na2S4) dissolved in the sodium hydroxide (NaOH) solution in the spray-dryer system. The effects of flue gas temperature and Na2S4 level in flue gas on the mercury removal efficiency were investigated. Na2S4 was decomposed into Na2S (S2-) and elemental S (S0), which reacted with HgCl2 and elemental Hg (Hg0), and HgS was then formed. Under the optimized operation parameters, this technology can simultaneously remove over 88% of HgCl2 and more than 90% of Hg0 from a flue gas stream containing about 400 microg m(-3) Hg0 and 1200 microg m(-3) HgCl2. The increased flue gas temperature (>170 degrees C) and the decreased Na2S4-to-Hg mass ratio (S-Hg-R) (<2.0) had negative effects on the reactions of gaseous mercury (HgCl2 + Hg0) with ionic sulfur (S2-) and S0. All the experiments were conducted in a full scale hospital-waste incinerator with a capability of 20 tons per day (TPD).  相似文献   

8.
International investments in agriculture in the Arab region have increased considerably in recent years. This paper reviews foreign direct investment (FDI) in agriculture in the Arab region with an emphasis on Sudan, Egypt, and Morocco. The paper aims to (i) review past and current investment trends in the context of the unique characteristics of the region, including its food security challenges and resource constraints, and (ii) highlight some important policy issues to be addressed. Agriculture has traditionally received a very small share of international investments in the region (1–2% of total FDI), which largely focused on sectors other than primary agriculture. In the past few years, investments in agriculture have grown remarkably; particularly for resource-seeking investments, but information is incomplete as the changes are very rapid. Sudan is the primary destination for resource-seeking investments; Morocco and Egypt for market-seeking investments, mostly in food processing and fruit and vegetable production. Given the paucity of data, it is difficult to develop concrete policy recommendations. However, the analysis presented in this paper may be useful in guiding the development of FDI policies in the region, aimed at maximizing sustainable outcomes for both investors and host countries, with an emphasis on food security.  相似文献   

9.
《Journal of dairy science》2022,105(1):424-440
In Federal Milk Marketing Orders (FMMO), which use multiple component pricing schemas, farmers are paid for delivered quantity of butterfat, protein, and other solids, plus a producer price differential (PPD). The PPD captures the difference between the total handler obligations to the pool and the total component value of milk. In 2020, record negative PPD caused widespread frustration among dairy farmers. The primary objective of this research was to provide a comprehensive analysis of factors that affect PPD and to quantify their relative importance. We examined FMMO data from the past 10 yr including prices, utilizations, and tests. By decomposing the PPD, we were able to isolate the drivers of negative values. We found that long-term trends in usage, most importantly declining beverage milk and rising component tests, including both butterfat and protein, have substantially reduced PPD over the past decade. Class I milk pricing reform of 2018 exacerbated negative PPD in 2020, but we found that the PPD would have been negative even without that reform. The greatest contributor to recent negative PPD was the spread between cheese and milk powder prices, caused by shifts in demand due to the COVID-19 pandemic and USDA intervention cheese purchases. A range of policy modifications proposed to address negative PPD was evaluated.  相似文献   

10.
The European Commission has announced that it is considering legislation concerning further restrictions on cigarette tar and nicotine yields, as well as new provisions to regulate additives and the labelling of tobacco products. This report considers these issues and their relation to public health. In particular, we argue that further reductions in tar and nicotine yields as measured by the International Standards Organisation/Federal Trade Commission (ISO/FTC) method will be largely cosmetic and certainly misleading to consumers. If a new directive uses the ISO/FTC methodology as a basis for regulation, it risks lending further official support to the concept of "low tar" cigarettes, which may be used by smokers as an alternative to smoking cessation. Although new regulations based on the ISO/FTC methodology may appear to offer health gains, these will be illusory and there may even be negative health consequences, as has been the case with these tests up to the present. We therefore make the following recommendations for the way forward.  相似文献   

11.
Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are widely detected in human blood and serum and are of concern due to their potential toxicity. This study investigated the indoor sources of these compounds and their neutral precursors through a survey of 152 homes in Vancouver, Canada. Samples were collected of indoor air, outdoor air, indoor dust, and clothes dryer lint and analyzed for neutral [i.e., fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamide (FOSA), and perfluorooctane sulfonamidoethanol (FOSE)] and ionic [i.e., PFOS and perfluoroalkyl carboxylates (PFCAs)] poly- and perfluorinated compounds (PFCs). Indoor air was dominated by 8:2 FTOH with a geometric mean concentration (pg/m(3)) of 2900. Among the FOSAs and FOSEs, MeFOSE exhibited the highest air concentration with a geometric mean of 380 pg/m(3). PFOA was the major ionic PFC and was detected in all indoor air samples with a geometric mean of 28 pg/m(3), whereas PFOS was below the detection limit. The results for the ionic PFCs in indoor air are the first for North America. The pattern of the neutral PFCs in house dust was also dominated by 8:2 FTOH, with a geometric mean of 88 ng/g. Dusts were enriched (relative to air) with sulfonamidoethanol (FOSE) which comprised ~22% of the total neutral PFC content compared to only ~3% in air. PFOS and PFOA were the most prominent compounds detected in dust samples. Levels of neutral PFCs in clothes dryer lint were an order of magnitude lower compared to house dust. Human exposure estimates to PFCs for adults and children showed that inhalation was the main exposure route for neutral and ionic PFCs in adults. For toddlers, ingestion of PFCs via dust was more relevant and was on the order of a few mg/day. Results from this study contribute to our understanding of exposure pathways of PFCs to humans. This will facilitate investigations of related health effects and human monitoring data.  相似文献   

12.
There is an urgent need globally to find alternative sustainable steps to treat municipal solid wastes (MSW) originated from mismanagement of urban wastes with increasing disposal cost. Furthermore, a conglomeration of ever‐increasing population and consumerist lifestyle is contributing towards the generation of more MSW. In this context, vermicomposting offers excellent potential to promote safe, hygienic and sustainable management of biodegradable MSW. It has been demonstrated that, through vermicomposting, MSW such as city garbage, household and kitchen wastes, vegetable wastes, paper wastes, human faeces and others could be sustainably transformed into organic fertiliser or vermicompost that provides great benefits to agricultural soil and plants. Generally, earthworms are sensitive to their environment and require temperature, moisture content, pH and sometimes ventilation at proper levels for the optimum vermicomposting process. Apart from setting the optimum operational conditions for the vermicomposting process, other approaches such as pre‐composting, inoculating micro‐organisms into MSW and redesigning the conventional vermireactor could be introduced to further enhance the vermicomposting of MSW. Thus the present mini‐review discusses the potential of introducing vermicomposting in MSW management, the benefits of vermicomposted MSW to plants, suggestions on how to enhance the vermicomposting of MSW as well as risk management in the vermicomposting of MSW. Copyright © 2010 Society of Chemical Industry  相似文献   

13.
Anaerobic polycyclic aromatic hydrocarbon (PAH) degradation is a key process for natural attenuation of oil spills and contaminated aquifers. Assessments by stable isotope fractionation, however, have largely been limited to monoaromatic hydrocarbons. Here, we report on measured hydrogen isotope fractionation during strictly anaerobic degradation of the PAH naphthalene. Remarkable large hydrogen isotopic enrichment factors contrasted with much smaller values for carbon: ε(H) = -100‰ ± 15‰, ε(C) = -5.0‰ ± 1.0‰ (enrichment culture N47); ε(H) = -73‰ ± 11‰, ε(C) = -0.7‰ ± 0.3‰ (pure culture NaphS2). This reveals a considerable potential of hydrogen isotope analysis to assess anaerobic degradation of PAHs. Furthermore, we investigated the conclusiveness of dual isotope fractionation to characterize anaerobic aromatics degradation. C and H isotope fractionation during benzene degradation (ε(C) = -2.5‰ ± 0.2‰; ε(H) = -55‰ ± 4‰ (sulfate-reducing strain BPL); ε(C) = -3.0‰ ± 0.5‰; ε(H) = -56‰ ± 8‰ (iron-reducing strain BF)) resulted in dual isotope slopes (Λ = 20 ± 2; 17 ± 1) similar to those reported for nitrate-reducers. This breaks apart the current picture that anaerobic benzene degradation by facultative anaerobes (denitrifiers) can be distinguished from that of strict anaerobes (sulfate-reducers, fermenters) based on the stable isotope enrichment factors.  相似文献   

14.
Data are presented for PCBs and HCB measured by passive air samplers (SPMDs) along a latitudinal transect from the south of the UK to the north of Norway during 1998-2000. This work is part of an ongoing air sampling campaign in which data were previously gathered for 1994-1996. Comparisons of the masses of chemicals sequestered by the SPMDs during these different time intervals are used to investigate spatial and temporal trends. Results are discussed in the context of sources, long-range atmospheric transport, fractionation/cold condensation, and global clearance processes controlling ambient levels of POPs. Spatial trends show a decrease in absolute sequestered amounts of PCBs with increasing latitude i.e., with increasing distance from the source area. However, relative sequestered amounts of the homologue groups (expressed as a ratio to penta-PCB) show a clear latitudinal trend, with the relative contribution of the lighter congeners increasing with increasing latitude, providing evidence of latitudinal fractionation. Absolute amounts of HCB increase with latitude, suggesting this compound is undergoing cold condensation. Sequestered amounts of PCBs generally decreased between the two sampling periods by a factor 2-5 over 4 years, suggesting half-lives on the order of 1.7-4 years. The relative rates of decline (1998-2000 data as a percentage of the 1994-1996 data) were compared for different congeners and latitudes. No clear latitudinal trends were found, with all sites/congeners showing a similar marked decline over time to ca. 30% of the former value. We discuss the interpretation of these observations and conclude they imply that the underlying trends of current ambient levels of PCBs in European background air are still largely controlled by primary emissions, rather than recycling/secondary emissions from the major environmental repositories such as soils or water bodies.  相似文献   

15.
Diesel fuels, classified as environmentally friendly, have been available on the Swedish market since 1991. The Swedish diesel fuel classification is based upon the specification of selected fuel composition and physical properties to reduce potential environmental and health effects from direct human exposure to exhaust. The objective of the present investigation was to compare the most stringent, environmentally classified Swedish diesel fuel (MK1) to the reference diesel fuel used in the "European Program on Emissions, Fuels and Engine Technologies" (EPEFE) program. The study compares measurements of regulated emissions, unregulated emissions, and biological tests from a Volvo truck using these fuels. The regulated emissions from these two fuels (MK1 vs EPEFE) were CO (-2.2%), HC (12%), NOx (-11%), and particulates (-11%). The emissions of aldehydes, alkenes, and carbon dioxide were basically equivalent. The emissions of particle-associated polycyclic aromatic hydrocarbons (PAHs) and 1-nitropyrene were 88% and 98% lower than those of the EPEFE fuel, respectively. The emissions of semi-volatile PAHs and 1-nitropyrene were 77% and 80% lower than those from the EPEFE fuel, respectively. The reduction in mutagenicity of the particle extract varied from -75 to -90%, depending on the tester strain. The reduction of mutagenicity of the semi-volatile extract varied between -40 and -60%. Furthermore, the dioxin receptor binding activity was a factor of 8 times lower in the particle extracts and a factor of 4 times lower in the semi-volatile extract than that of the EPEFE fuel. In conclusion, the MK1 fuel was found to be more environmentally friendly than the EPEFE fuel.  相似文献   

16.
本文介绍了美国和欧盟国家关于溴素的包装形式、规格、包装容器的相关规定,包装容器和运输工具的危险品标志张贴规定,运输溴素的规定及紧急救援、处理事故的规定,溴素使用和存储的规定和防护设备的规定。  相似文献   

17.
Long-term air monitoring data sets are needed for persistent organic pollutants (POPs), to assess the effectiveness of source abatement measures and the factors controlling ambient levels. The Toxic Organic Micro-Pollutants (TOMPS) program in the United Kingdom started in 1991, generating a data set for polychlorinated biphenyls (PCBs). The history and volumes of production, usage, and subsequent restrictions on PCBs in the UK are well-characterized relative to many countries, providing a valuable case study on the effectiveness of controls and the factors influencing ambient levels and trends of these "model POPs". PCB air concentrations (congeners PCB 28, 52, 90/101, 118, 138, 153, and 180) from six rural and urban monitoring sites are presented. Most show a statistically significant decrease in PCBs levels over time, consistent with estimates of emissions, helping to validate emissions inventories. Times for a 50% decline in concentrations (sometimes called clearance rates) averaged 4.7 ± 1.6 years for all congeners at all sites. The trends at different sites and for different congeners were not statistically different from each other. Concentration differences between sites are correlated with local population density (i.e., the degree of urbanization), which supports approaches to modeling of primary emissions on the national and regional scale. The data set indicates that ambient levels and underlying trends of PCBs continue to reflect the controlling influence of diffuse primary sources from the ongoing stock of PCBs in urban environments. Production and use restrictions came into force in the UK over 40 years ago; trends since monitoring began in the early 1990s should be seen as part of a continuing decline in ambient levels since that time.  相似文献   

18.
The influence of air-conditioning activity on the emissions and fuel consumption of passenger cars is an important issue, since fleet penetration and use of these systems have reached a high level. Apart from the MOBILE6 study in the United States, little data is available on the impact of air-conditioning devices (A/Cs). Since weather conditions and A/C technologies both differ from those in the U. S., a test series was designed for the European setting. A fleet of six modern gasoline passenger cars was tested in different weather conditions. Separate test series were carried out for the initial cooldown and for the stationary situation of keeping the interior of the vehicle cool. As assumed, CO2 emissions and fuel consumption rise with the thermal load. This also causes a notable rise in CO and hydrocarbons (HCs). Moreover, A/Cs do not stop automatically at low ambient temperatures; if necessary, they produce dry air to demist the windscreen. A model is proposed that shows a constant load for lower temperatures and a linear trend for higher temperatures. The initial cooldown tests highlight significant differences among cars but show that A/C operation for the initial cooling of an overheated passenger compartment does not result in any extra emissions for the fleet as a whole.  相似文献   

19.
Chromium-containing wastes from various industrial sectors are under critical review. Leather processing is one such industrial activity that generates chromium-bearing wastes in different forms. One of them is chrome shavings, and this contributes to an extent of 10% of the quantum of raw skins/hides processed, amounting to 0.8 million ton globally. In this study, the high protein content of chrome shavings has been utilized for reduction of chromium(VI) in the preparation of chrome tanning agent. This approach has been exploited for the development of two products: one with chrome shavings alone as reducing agent and the other with equal proportion of chrome shavings and molasses. The developed products exhibit more masking due to the formation of intermediate organic oligopeptides. This has been corroborated through the spectral, hydrolysis, and species-wise distribution studies. The formation of these organic masking agents helps in chrome tanning by shifting the precipitation point of chromium to relatively higher pH levels. Hence, the developed products find use as chrome tanning agents for leather processing, thus providing a means for better utilization of chrome shaving wastes.  相似文献   

20.
Over the last 20 years educational policies across the globe have become more closely aligned with industry interests. Jamaica is no exception. But what does this mean when the country's leading 'industry' is tourism? It is no coincidence that in this decade the Ministry for Education became the Ministry for Education and Culture. When one of the main threats to the industry is seen to be the country's reputation for violence as substantiated by rising murder rates and increasingly vicious crime scenarios, what is the Ministry's response? One has been the introduction of the PALS (Peace and Love in Schools) curriculum, underwritten by the Tourist Board. The article examines the texts within this curriculum and how they position the identity of children and adults, and distinguish between Jamaicans and foreigners. The author then examines material collected during ethnographic fieldwork in the summer of 2000 with Jamaican youth in which issues of violence, tourism and the marketing of cultural products come to the fore. The youth convey an understanding of the facade/reality dichotomy that tourism necessitates across a wide spectrum of activities that make up daily life, and a pragmatism in which innocence is an unaffordable luxury, as are some forms of resistance to the inequalities that tourism brings so prominently into focus in the shape of all-inclusive hotels and cruise ships. The children's experiences resonate tellingly with some of the Caribbean's leading critical thinkers' misgivings about the tourism project and the schism in identities that it perpetuates.  相似文献   

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