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1.
Studies were made to assess the impact of a thermal power plant located at Obra on vegetation and soil in surrounding areas. Pollutant concentration in the area gradually decreased along a belt in the prevailing wind direction and a gradient of structural and functional changes in plants and soil was observed. Natural vegetation in the area varied significantly at different sites and on the basis of plant responses can be classified as insensitive, intermediate and sensitive. The effect of the power plant emissions on soil and eco-physiological characteristics such as pH, organic matter and N, P, K and S concentrations in soil; leaf injury symptoms, number and distribution of plant species; chlorophyll content in leaves, percentages of photosynthetically active leaf area; accumulation of N, P, K, and S in leaves etc. seemed to be a function of the pollutant gradient existing in the area. There was a relationship between plant responses and changes in the chemical factors of soil and plants due to pollution. This study indicates possible elimination of plant species, first the trees then the shrubs and lastly the herbs and grasses from the environs of the thermal power plant. The increase in soil acidity in the area may cause cation-anion imbalance and microbe population reduction to affect soil fertility. 相似文献
2.
Peanuts are one of the most common and severe food allergens. Nevertheless, the occurrence of peanut allergy varies between countries and depends on both the exposure and the way peanuts are consumed. Processing is known to influence the allergenicity of peanut proteins. The aim of this study was to assess the effect of thermal processing on the IgE-binding capacity of whole peanut protein extracts and of the major peanut allergens Ara h 1 and Ara h 2. Whole proteins, Ara h 1, and Ara h 2 were extracted and purified from raw, roasted and boiled peanuts using selective precipitation and multiple chromatographic steps, and were then characterized by electrophoresis and mass spectrometry. The immunoreactivity of whole peanut extracts and purified proteins was analyzed by the enzyme allergosorbent test (EAST) and EAST inhibition using the sera of 37 peanut-allergic patients. The composition of the whole protein extracts was modified after heat processing, especially after boiling. The electrophoretic pattern showed protein bands of low molecular weight that were less marked in boiled than in raw and roasted peanuts. The same low-molecular-weight proteins were found in the cooking water of peanuts. Whole peanut protein extracts obtained after the different processes were all recognized by the IgE of the 37 patients. The IgE-binding capacity of the whole peanut protein extracts prepared from boiled peanuts was 2-fold lower than that of the extracts prepared from raw and roasted peanuts. No significant difference was observed between protein extracts from raw and roasted peanuts. It is noteworthy that the proteins present in the cooking water were also recognized by the IgE of peanut-allergic patients. IgE immunoreactivity of purified Ara h 1 and Ara h 2 prepared from roasted peanuts was higher than that of their counterparts prepared from raw and boiled peanuts. The IgE-binding capacity of purified Ara h 1 and Ara h 2 was altered by heat treatment and in particular was increased by roasting. However, no significant difference in IgE immunoreactivity was observed between whole protein extracts from raw and roasted peanuts. The decrease in allergenicity of boiled peanuts results mainly from a transfer of low-molecular-weight allergens into the water during cooking. 相似文献
3.
The contribution to local wet deposition of emissions from a coal-fired power station at Inkoo on the south coast of Finland has been investigated during a wintertime precipitation event. Making use of intensive radiosonde and weather radar observations of meteorological factors, concentrations of sulphur in deposition due to plume washout were predicted by a short-range deposition model. The model used the scavenging coefficient to parametrize the wet removal of pollutants, and it took into account the wind drift of falling precipitation particles within the plume. The model predictions were then compared with the chemical analysis results from snowfall samples collected within 10 km of the power station during the experiment.The experiment was performed ahead of a deeply-occluded front during a period with strong advection of long-range transported pollutants. No reliable sign of the influence of the power station on the sulphate deposition could be identified. On the other hand, the deviations of acidity from the mean pH-value of 4.1 were concentrated in one sector near the expected area of deposited plume pollutants. If local emissions were responsible for these deviations, the explanation may lie in a slightly incorrectly estimated plume direction or the effects of alkaline fly ash. Nevertheless, definite conclusions cannot be drawn, because only a few collectors happened to be sited in the modelled sector of plume washout and none in its maximum area. 相似文献
4.
Beryllium enters the environment principally from coal combustion. Be contents in the ashes from a Czechoslovak power plant were determined. The ashes used in the experiment were as follows: coarse (> 2.0 mm) and fine (2.0 to 0.2 mm) fraction from dump, and fine (< 0.2 mm) fraction from electrostatic precipitators. It was discovered that the acidic and the alkali aqueous extracts of these ashes contain various concentrations of Be (1 to 17% of total concentration). Wastewater has shown 3.15 and 3.4 μg Be L ?1. Thus, secondary long-term Be pollution emerges from the slag and ash dumps. 相似文献
5.
The influence of thermal treatment on black currant juice aroma was investigated in temperature and time ranges relevant for black currant juice concentration processes, namely, 45, 60, 75, and 90 degrees C. Forty-nine aroma compounds were quantified, and the thermal treatment resulted in concentration increases of most terpenes, aldehydes, furans, and phenols, whereas the concentration of esters slightly decreased. Higher temperatures and longer exposure times had larger effects on the aroma compounds. Odor triangle tests showed no sensory difference between pasteurized juice and juice heated at 60 degrees C, whereas juice heated at 90 degrees C differed significantly from pasteurized juice. It is concluded that a 90 degrees C thermal treatment of black currant juice, which is in the temperature range used for conventional evaporation of black currant juice, has an effect on the aroma and sensory properties. 相似文献
6.
Virgin olive oils were subjected to simulated common domestic processing, including frying, microwave heating, and boiling with water in a pressure cooker. The impact of these processes on polyphenol content and physicochemical characteristics of oils was assessed. Thermal oxidation of oils at 180 degrees C caused a significant decrease in hydroxytyrosol- and tyrosol-like substances. In contrast, oils heated for 25 h still retained a high proportion of the lignans 1-acetoxypinoresinol and pinoresinol. Thermal oxidation also resulted in a rapid degradation of alpha-tocopherol and the glyceridic fraction of oils. Microwave heating of oils for 10 min caused only minor losses in polyphenols, and the oil degradation was lower than that in thermoxidation assays. Again, lignans were the least affected polyphenols and did not change during microwave heating. Boiling a mixture of virgin olive oil and water in a pressure cooker for 30 min provoked the hydrolysis of the secoiridoid aglycons and the diffusion of the free phenolics hydroxytyrosol and tyrosol from the oil to the water phase. Losses of polyphenols were detected only at pH lower than 6. Moreover, alpha-tocopherol and the glyceridic fraction of oils were not modified during this process. It is worth noting that all the heating methods assayed resulted in more severe polyphenols losses and oil degradation for Arbequina than for Picual oil, which could be related to the lower content in polyunsaturated fatty acids of the latter olive cultivar. These findings may be relevant to the choice of cooking method and olive oil cultivar to increase the intake of olive polyphenols. 相似文献
7.
The effects of sewage pollution on the distribution and abundance of some orgnanisms over a period of 4 mo at the Ahmadu Bello University Main Campus sewage treatment plant and Kubanni river were studied. Physico-chemical parameters such as dissolved oxygen; temperature; hydrogen ion concentration (pH); electrical conductivity and chemical oxygen demand influenced by pollution were measured with respect to the population of aquatic organisms. The organisms were used as biological indices to monitor the ecological imbalance caused by the effluent. The variations in concentrations of some heavy metals were also measured. The studies revealed that at the source of pollution there were no organisms except for some insect larva such as Eristalis, Psychoda, and some microscopic algae like Oscillatoria, Anaebaena, and Polysystis. A location (site 5) on Kubanni river just before the confluence of the sewage effluent and the river was taken as the control. There was a wide variety of organisms (crustaceans, rotifers, and fish) at the control point. 相似文献
8.
The influence of sucrose (0-40 wt %) on the thermal denaturation and functionality of whey protein isolate (WPI) solutions has been studied. The effect of sucrose on the heat denaturation of 0.2 wt % WPI solutions (pH 7.0) was measured using differential scanning calorimetry. Sucrose increased the temperature at which protein denaturation occurred, for example, by 6-8 degrees C for 40 wt % sucrose. The dynamic shear rheology of 10 wt % WPI solutions (pH 7.0, 100 mM NaCl) was monitored as they were heated from 30 to 90 degrees C and then cooled to 30 degrees C. Sucrose increased the gelation temperature and the final rigidity of the cooled gels. The degree of flocculation in 10 wt % oil-in-water emulsions stabilized by 1 wt % WPI (pH 7.0, 100 mM NaCl) was measured using a light scattering technique after they were heated at fixed temperatures from 30 to 90 degrees C for 15 min and then cooled to 30 degrees C. Sucrose increased the temperature at which maximum flocculation was observed and increased the extent of droplet flocculation. These results are interpreted in terms of the influence of sucrose on the thermal unfolding and aggregation of protein molecules. 相似文献
9.
The environmental degradation of a mixture of domoic acid (DA) and kainic acid (KA) in seawater with and without added transition metals is reported. The association constants for kainic acid with Fe (III) and Cu (II) were determined using (1)H nuclear magnetic resonance (NMR; K1,Fe(III) = 2.27 x 10(12), K2,Fe(III) = 8.99 x 10(8), K1,Cu(II) = 1.38 x 10(10), and K2,Cu(II) = 4.35 x 10(7)). The photochemical half-life of kainic acid has been determined to be significantly longer (40-100 h) than that of domoic acid in corresponding marine systems (12-34 h). The significance of this finding was highlighted by a comparison of the quantification of a mixture of kainic and domoic acids during photodegradation by liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques and the widely used competitive enzyme-linked immunosorbent assay (cELISA; Biosense Laboratories) method. The MS-based analysis showed that approximately 50% of the DA was photodegraded within 15 h. In contrast, the domoic acid cELISA assay reported that the concentration essentially remained unchanged over this period. The possibility of interference from naturally occurring kainic acid during cELISA measurements could lead to the overestimation of total domoic acid, especially if they occur in mixtures in sunlit waters. 相似文献
10.
This investigation was conducted to determine the elemental composition of effluents from three anaerobic swine waste lagoons and one aerobic swine waste lagoon and to evaluate effects of effluent application on growth of corn ( Zea mays L.) Wide variation occurred in the elemental composition of effluents among the four lagoons and among four sampling dates from each lagoon. Use of these effluents as irrigation water would lead to application of a wide range in amounts of nutrients to soil. Effluent application increased corn grain yield on a Woodstown loamy fine sand. This yield increase was attributed to alleviation of moisture stress and to correction of N deficiency. 相似文献
11.
The objectives of this study were to determine and to reduce phytotoxicity of two industrial effluents. Phytotoxicity of the treated and untreated samples was determined using millet seed germination test. The results of this and other studies showed that the test was reproducible and useful for effluent toxicity determination. Effluent sample I was from an industrial wastewater pretreatment plant and sample II was from a specialty chemical industry. Sample I was weakly acidic and sample II was alkaline. pH adjusted to 7 to 8 was found to have no effect in phytotoxin removal. Granular and powdered activated carbon effectively reduced phytotoxicity. Amberlite XAD-4 (nonionic polymeric adsorbent) and cation exchange resin had a partial effect. Anion exchange resin, silica gel, Sephadex G-75, and starch xanthate had no effect. 相似文献
12.
A method was developed to fractionate chloride ions from complex effluents using an ion exchange column. The procedure utilizes a strongly basic anion exchange resin with hydroxide ions as the exchange ion. The chloride within the effluent is exchanged for hydroxide which is less toxic to Ceriodaphnia dubia. The addition of hydroxide to the solution requires a pH adjustment to a physiologically acceptable pH for Ceriodaphnia with an acid. The fractions are added to Ceriodaphnia and the ET 50 (median lethal time) determined. The column was applied to two effluents with suspected chloride toxicity. The column successfully removed virtually all of the chloride from the effluents. A significant reduction in toxicity was found following the process for one of the effluents. In addition, a control that consisted of the original effluent at the ionic strength of the column fractions revealed that chloride was a causative toxicant in both of the effluents. 相似文献
13.
Abstract A capillary rise experiment was conducted by passing different organic industrial effluents [liquor distillery effluent (DE), cotton seed delinting plant effluent (CD), and sewage water (SW)] through soils with two different textures. The validity of Poiseuille's law was verified in the first time segment by a straight line relationship between wetting front rise velocity dz/dt and the inverse of the wetting front rise I/Z. The soil geometrical and transmission characteristics (e, G, r, X, and k) were estimated by a quick capillary rise (QCR) approach. The liquor distillery effluent was found to have the lowest flow velocity through both types of soils due to its lower surface tension higher viscosity and density than those of ordinary water. Due to the acidic nature, CD could not be used for irrigating the fields, whereas, SW was not found to have any harmful effects on its flow behavior in the soils. 相似文献
14.
Intercalation of vermiculite with Fe(III) polyhydroxy cations at 1:1 and 2:1 [OH-]/[Fe(III)] molar ratios increases the affinity of the clay mineral toward atrazine in comparison with potassium saturated vermiculite. The present paper describes the effects of thermal treatments applied to Fe(III) polyhydroxy cations modified vermiculite on the adsorption properties of the clay mineral. Only small changes in the textural characteristics were observed for the materials intercalated with either 1:1 or 2:1 [OH-]/[Fe(III)] molar ratios treated at 100 and 250 degrees C. In comparison with potassium saturated vermiculite, or intercalated vermiculite treated at 100 degrees C, a significant enhancement in the adsorption of atrazine was observed for the materials treated at 250 and 400 degrees C, which removed more than 95.8 and 99.5% of the herbicide initially present in a 50.0 microg L-1 aqueous solution, respectively. In comparison with potassium saturated vermiculite and intercalated vermiculite treated at 100 degrees C, a lower desorption degree of preadsorbed atrazine was observed for both intercalated materials treated at 250 and 400 degrees C. These findings suggest that the thermal treatment produced modified vermiculite materials with a high adsorption capacity and high affinity toward atrazine, with potential application in the removal of this herbicide, as well as other triazines, from aqueous medium. 相似文献
15.
近些年来电力行业发展迅速,地方电力企业纷纷建立了自己的用电管理信息系统,用来解决电力行业的发展需要。而如何通过新的信息技术使电力企业能够为用户提供更加优质高效的服务,提高企业经济效益,是当前电力企业用电管理信息系统建设的首要问题。本文介绍了采用面向对象的C.#和SQL Server 2000设计的用电管理信息系统,用以解决地方电力企业用电管理信息化的需要。 相似文献
16.
Distillery effluent, a waste by-product of distillery industries, is usually applied to arable land near the distilleries as irrigation water or as a soil amendment. To evaluate the effect of distillery effluent, both spent wash (SW) and post-methanated effluent (PME), on soil organic carbon and aggregate stability, a field experiment on a soybean ( Glysine max L.)–wheat ( Triticum aestivum L.) system was conducted for five years on a Vertisol of central India. The treatments were control (no fertilizer or manure or SW or PME, T 1), 100% NPK + farmyard manure (FYM) @ 4 Mg ha −1 to soybean (T 2), four graded levels of SW, viz., 2.5 cm SW to soybean and none to wheat (T 3), 2.5 cm SW to soybean and 1.25 cm to wheat (T 4), 5 cm SW to soybean and none to wheat (T 5), 5 cm SW to soybean and 2.5 cm to wheat (T 6), and four graded levels of PME, viz., 2.5 cm PME to soybean and none to wheat (T 7), 2.5 cm PME to soybean and 1.25 cm to wheat (T 8), 5 cm PME to soybean and none to wheat (T 9), 5 cm PME to soybean and 2.5 cm to wheat (T 10). The organic carbon of the surface (0–15 cm) soil that received either PME or SW (treatments T 3–T 10), was significantly ( P < 0.05) higher than in treatments T 1 and T 2. The mean weight diameter (MWD) of water stable aggregates in this soil layer was also significantly higher in treatments T 3–T 10, compared with T 1 and T 2. The MWD showed a positive linear relationship with the organic carbon content of the soil ( R2 = 0.54**). The proportion of macro-aggregates was higher in SW treated plots than PME, no distillery effluents and NPK + FYM treatments. However, the micro-aggregates showed the reverse trend. The macro-aggregate-associated carbon was higher in SW treated plots. It was highest in T 6 and lowest in T 1. The plots receiving the PME and SW showed increased soil organic carbon, MWD, percentage macro- and micro-aggregate-associated carbon than T 1 and T 2. Application of distillery effluents increased the aggregate stability of the Vertisol through enhanced soil organic carbon as well as the aggregate-associated carbon. So application of SW or PME could be a viable option for soil aggregate stability and enhanced productivity. 相似文献
17.
Observations on gaseous and particulate pollutants were undertaken at four locations in the region of a thermal power plant (TPP), which is under construction at Tuticorin, south India. The predicted concentrations Of SO 2 due to the emissions from the TPP and its possible impact on the inhabitants and climate in the downwind region were evaluated. Also, the predicted concentrations downwind of a Petrochemical Industrial Complex (PIC) located in the vicinity of the TPP were computed and compared with the measured concentrations. The predicted maximum concentration of SO 2 at 6 km downwind of TPP is about 530 μg m ?3 under most favourable wind conditions. The anticipated increase in SO 2 due to the thermal power plant under construction may therefore be substantial. The predicted concentrations Of SO 2, at a distance of 1.8 km downwind of the PIC, varied between 34 and 216 μg m ?3 for wind directions ranging from 70 to 90° and for Pasquill stability category C. The plume would be over the observational site when the wind direction is 80°. The maximum measured concentration was 23 ug m ?3. The discrepancy was due to the rapid fluctuations in the wind direction during the observational period over a wide range from 20 to 90°. 相似文献
18.
利用不同稀释倍数的生活污水(污水∶清水,V/V,分别为1∶0;1∶1;1∶2;0∶1)浇灌长春花结果表明,与清水灌溉相比,污灌处理土壤NH4 -N含量由59.01mg/kg提高到64.22~65.89mg/kg,NO3--N含量由2.69mg/kg提高到3.03~4.54mg/kg,速效磷含量由32.29mg/kg提高到37.40~42.41mg/kg;增加了土壤酶活性,其中土壤过氧化氢酶、脲酶及蛋白酶活性分别比对照提高10.76%~23.32%、33.41%~103.69%和31.82%~131.82%;植物根系活性由170.25μg/g.h提高到177.88~471.69μg/g.h,叶绿素含量由1.78mg/dm2提高到2.68~2.98mg/dm2,植物干物质量由11.660g/盆提高到12.130~16.577g/盆。且以稀释1倍污水灌溉处理效果最佳。用原生生活污水直接灌溉虽降低污水肥效,造成土壤Cl-的积累,但对长春花生长及干物质积累无显著影响。 相似文献
19.
Chemistry of effluents entering natural water bodies is usually ecological chemistry. The object of its study is the influence of effluents on chemical and biological processes of self-purification. Mercury and its compounds are priority pollutants in bleached kraft pulp mill effluents. It is ascertained that Hg enters the effluents from wood and auxiliary reagents: compounds of Na and active Cl and also from H 2SO 4 employed for neutralization of effluents before biological treatment. At the investigated enterprise the effluents have three stages of treatment: biological, physico-chemical and mechanical. This treatment reduces the Hg concentration in effluents from 10 to 30 ppb to 0.3 to 0.5 ppb. No increased Hg accumulation by aquatic organisms and bottom sediments in the area of effluent discharge was found. Moreover, aquatic organisms grown during 1 mo in the effluents medium did not accumulate Hg in comparison with the control animals. It is found that such ecological effect is obtained as a result of inclusion the modern physico-chemical methods into the complex treatment system. 相似文献
20.
不同沸石分别与硝酸铵混合压片和硝酸铵熔融盐反应制备沸石氮肥,利用水冲洗和土壤淋溶法对它们的释放特性进行初步评价和比较。发现熔融盐反应制备的沸石氮肥比用压片法制备的沸石氮肥具有更强的抗水冲洗和土壤盐溶液溶解能力,在平稳释放的过程中负载硝酸铵的量也较高。他们以较低的浓度平稳释放,具有一定缓慢释放的效果。 相似文献
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