174 research outputs found
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Citric Acid-Modified Fenton's Reaction for the Oxidation of Chlorinated Ethylenes in Soil Solution Systems
Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in-situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic contaminant removal in Fenton's reaction, and examined the impacts of using citric acid on the unwanted reaction products. A series of batch and column experiments were performed with varying H{sub 2}O{sub 2} concentrations to decompose selected chlorinated ethylenes. Either dissolved iron from soil or iron sulfate salt was added to provide the iron catalyst in the batch tests. Batch experiments revealed that both citric and sulfuric acid systems achieved over 90% contaminant removal rates, and the presence of iron catalyst was essential for effective decontamination. Batch tests with citric acid showed no signs of pressure accumulation and solid precipitations, however the results suggested that an excessive usage of H{sub 2}O{sub 2} relative to iron catalysts (Fe{sup 2+}/H{sub 2}O{sub 2} < 1/330) would result in lowering the efficiency of contaminant removal by iron chelations in the citric acid system. Column tests confirmed that citric acid could provide suitable acidic conditions to achieve higher than 55% contaminant removal rates
The effects of dietary supplementation with different levels of Microzist as newly developed probiotics on growth performance, carcass characteristics, and immunological organs of broiler chicks
The current research was conducted to evaluate the influence of newly developed probiotic (Microzist) and commercial probiotic (Primalac) on growth performance, carcass characteristics, and immunity of broiler chickens. A total of 225 one-day-old broiler chicks Ross-308 was randomly assigned into 5 groups – control group, group with 0.2, 0.25, and 0.3 g/kg of Microzist, and group constituting Primalac (starter: 0.9 g/kg, grower: 0.454 g/kg, and finisher: 0.225 g/kg). At 42nd day of age, there were no statistically significant differences among treatments on daily weight gain and feed conversion ratio (P > .05), but treatment’s effect on the feed intake was found to be significant (P < .05). Diet supplementation with various concentrations of Microzist showed growth performance of broiler chickens more or less similar to the Primalac additives. There were statistically significant differences (P < .05) among treatments on the carcass characteristics. Microzist (0.2 g/kg) reduced the abdominal fat content in broiler chickens in a comparison with control as well as Primalac (P < .05). Furthermore, Microzist showed no influence on the immunological organ weights. The present investigation indicates that Microzist may be a potential alternative to antibiotic growth promoters as well as widely used Primalac in broiler industries
The effects of antibiotic, probiotic, organic acid, vitamin C, and Echinacea purpurea extract on performance, carcass characteristics, blood chemistry, microbiota, and immunity of broiler chickens
The present context investigated the comparative study on the supplementation of antibiotic, probiotic, organic acid, vitamin C, and herbal extract after vaccination into drinking water and their effects on performance, carcass quality, blood biochemical parameters, immune system, and intestinal flora in broiler chicks for 42 days. A total of 420 one-day-old male broiler chicks (Ross 308) were randomly assigned into 7 treatments with 3 replicates (pens) per treatment and 20 male chicks for each replicate (pen). The experimental treatments consisted of drinking water (control, without additive); drinking water + antibiotic sulfamet; drinking water + CVet- 50; drinking water + antibiotic sulfamet + C-Vet-50; drinking water + probiotic Primalac; drinking water + butyric acid; and drinking water + extract of Echinacea purpurea Moench (coneflower). There were no differences observed among the treatments for feed intake, but during the whole experimental period, the highest body weight gain was found in the chicks fed with drinking water + antibiotic sulfamet + 50 cc vitamin C (P 0.05) observed among the treatments for feed conversion ratio (P > 0.05). Moreover, there were no differences reported among treatments for carcass characteristics at the end of the experiment. Among the treatments, drinking water + 50 cc vitamin C, and drinking water + extract of E. purpurea reduced (P < 0.05) the levels of cholesterol, triglycerides, and low-density lipoproteins. Drinking water + 50 cc vitamin C, drinking water + Primalac, and drinking water + extract of E. purpurea increased (P < 0.05) the lymphocytes count and decreased the heterophils count and heterophil:lymphocyte ratio. The highest Escherichia coli count and lowest Lactobacillus count in ileal content of the broilers were observed in the control group (P < 0.05)
A Stochastic Analysis of Pumping Tests in Laterally Nonuniform Media
This is the published version. Copyright American Geophysical UnionConventional pumping test analysis methodology assumes that aquifer transmissivity is invariant in space. The ramifications of this assumption are examined for hypothetical units whose variations in transmissivity are considered to be reasonable representations of variations possible in natural systems. The dependence of pumping test transmissivity on spatial (angular and radial) and temporal location of observations and the method of drawdown analysis is assessed. The dependence on the angular position of an observation well appears of little significance. Dependence on radial position, however, can be strong. The dependence on the interval of time used in the pumping test analysis is only important in highly variable systems. Methods of drawdown analysis that yield identical estimates in uniform units yield differing estimates in nonuniform ones as a result of a difference in data-fitting procedures. A reasonable estimate of transmissivity at a regional scale can be obtained from a Cooper-Jacob analysis applied at a large duration of pumpage. In general, conventional approaches for pumping test analysis should be viable in the nonuniform aquifers of the type considered here
Effect of a multivitamin complex and probiotic blend in drinking water before and after vaccination on performance traits, blood biochemistry and humoral immune response of broilers
This study was conducted in order to investigate the effects of a multivitamin complex and probiotic blend in drinking water before and after vaccination on growth performance, carcass traits, blood biochemical parameters and humoral immune response of broiler chickens. A total of 150 one day-old male broiler chicks (Ross 308) were randomly allocated to five treatment groups, with three replicates (10 birds per replicate) in a completely randomized design. Experimental treatments consisted of: 1) a basal diet and drinking water without any additives as control (C); 2) C + drinking water + multivitamin complex from 2 days before vaccination until 3 days after vaccination; 3) C + drinking water + multivitamin complex for 3 days after vaccination; 4) C + drinking water + probiotic blend from 2 days before vaccination until 3 days after vaccination; and 5) C + drinking water + probiotic blend for 3 days after vaccination. In the whole experimental period, feed intake, body and thigh weight and abdominal fat were significantly affected (P<0.05) by dietary treatments. On the contrary, no significant effect was observed on carcass characteristics, feed conversion ratio, blood parameters, antibody production against SRBC and IgG. The titer of IgM was higher in treatment (2) than other treatments at 28 d of age (P<0.05). In conclusion, a multivitamin complex supplied in drinking water for 2 days before vaccination till 3 days after vaccination is enable to improve broiler performance and immunity
Effect of sumac (Rhus coriaria L.) seed powder on growth, carcass traits, blood parameters, immune system and selected ileal microorganisms of broilers
Sumac (Rhus coriaria L.) is a plant species belong to Anacardiaceous family that is worldwide diffused. The sumac seed power (SSP), produced by grinding dried fruits, is recognized to have defensive and beneficial effects on numerous health‑related problems. In this study, SSP was included in broilers basal‑diet to investigate the comparative effects of different
levels of SSP on performance, carcass characteristics, blood parameters, immune system and ileal microorganisms. A total of 225, one day‑old male broilers (Ross 308) were randomly assigned to the five dietary treatments with three replicates per treatment. The experimental diets were: basal‑diet (BD); and BD including 0.05, 0.10, 0.15 and 0.20% SSP, respectively.
During the whole feeding period (42 days), birds fed corn‑based grower (1‑21 days) and finisher (22‑42 days) diets, respectively. Results indicated that supplementing SSP had no effect on broiler body weight gain, feed intake and feed conversion as well as carcass characteristics (P > 0.05). Similarly, blood total protein, albumin, glucose and triglyceride
were not influenced by dietary SSP. Conversely, serum total cholesterol and LDL‑cholesterol levels were decreased, while HDL‑cholesterol increased in all SSP fed groups compared to control (P < 0.05). In this study the addition of SSP in broilers diets did not show any effect on blood heterophils and lymphocyte. Moreover, the lactobacillus count remained unaffected by dietary treatments, while E. coli count in broiler ileal content was lower when fed 0.10% SSP than the other groups (P < 0.05). Thus, the present findings indicated a positive effect of feeding SSP (especially at 0.10% diet) on blood cholesterol levels and
E. coli count in broiler chickens
Hydraulic barrier design and applicability for managing the risk of CO2 leakage from deep saline aquifers
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A SEMI-ANALYTICAL SOLUTION FOR PARTIAL PENETRATION IN TWO-LAYER AQUIFERS
Techniques for measuring the vertical hydraulic conductivity of flood basalts at the Basalt Waste Isolation Project site
A regional model that can predict groundwater movement through the reference repository location and surrounding area is essential to assessing the site suitability for a nuclear waste repository. During the last two decades, several models have been developed to handle complicated flow patterns through complex geologic materials. The basic problem, however, is obtaining the data base needed to apply these models. The hydrological data needed include the spatial distribution of effective porosity, the hydraulic conductivity tensor and its variation in space, values of specific storage, the hydraulic head distribution, and the fluid properties. In this report, we discuss conventional methods of obtaining vertical hydraulic conductivity and examine their applicability to the BWIP site. 39 references, 12 figures, 4 tables
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