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In this work, uranium(VI) sorption from aqueous sulphate medium using tri-n-octylamine impregnated Siplite LX-16 resin has been investigated using batch experiments. The sorption parameters includi...

Impregnation of tri-n-octylamine (TOA) into Siplite LX-16 resin, by two commonly used methods namely; wet and dry impregnation method, was studied and applied for uranium extraction from sulfate medium. The resin beads were characterized using FT-IR and FE-SEM analysis. The influence of different parameters such as effect of TOA concentration, pH, aqueous sample and eluant flow rates were investigated. Maximum sorption of U(VI) was obtained using 30% TOA/Siplite LX-16 prepared by the dry method at a pH range of 1.4–1.6. Flow rate of 1.0 mL/min for the pregnant sample was favorable for quantitative sorption of uranium during the extraction step while the flow rate of 0.5 mL/min for eluant solution was effective for the elution step. TOA-impregnated Siplite LX-16 resin has been properly prepared and applied for U(VI) extraction from sulfuric acid medium.

In present study, uranium (VI) extraction from different acidic media (e.g. H2SO4, HCl and HNO3 aqueous solutions) using tri-n-octylamine (TOA) impregnated into Siplite LX-16 polymeric resin has been investigated using batch experiments. The extraction parameters including aqueous pH, free acidity, salting-out agent addition, initial uranium concentration, volume of aqueous solution to weight of the impregnated resin (v/w) ratio and the phases contact time have been studied. Batch adsorption studies reveal that the prepared TOA/Siplite LX-16 has a significant capacity for the adsorption of U(VI) from aqueous solutions. The maximum sorption capacity of U(VI) from sulfate solution onto the working resin was 92.74 mg/g at an optimum pH range from 1.4 to 1.6. Quantitative desorption of the extracted uranium has successfully been achieved using 0.75 M NaCl acidified with 0.15 M HCl solution. Finally, a complete precipitation of uranium from the eluate solution was attained by hydrogen peroxide precipitation at pH 2.

This study aimed to evaluate the effect of Ca soap of palm oil fatty acids (CSFA), as a protected fat, on milk composition and the performance of both ewes and lambs. Thirty-three crossbred ewes aged 2-3 years and weighed 41-44 kg were allocated in three unequal groups for A, B &C (10, 12 &11 ewes, respectively). Group A was fed a diet free from protected fat and kept as a control. Group B was fed a diet containing 4 % fat and group C was given a diet containing 8 % fat. The ewes were in the last month of pregnancy and the experiment extended till the end of late lactation (4.5 months). Milk composition was tested, and body change in ewes and nursing lambs was traced. Moreover, the effect of fat addition on dry matter intake of ewes was analyzed. Results revealed a decrease in dry matter intake in the late gestation and an increase in early lactation, with no significant differences in the late lactation. The effect followed the amount of fat added. There was no effect on ewe’s body weight change or lamb’s growth rate from birth to weaning. On milk composition, there was an increase in fat %, higher in group B and total solids%, while percentage of protein was decreased. Concerning fat supplementation, no effect on lactose, urea milk nitrogen, and somatic cell counts was detected. There was a decreased level of solids-not-fat in group B, while group C showed no detectable alterations. In conclusion CSFA supplementation was effective to increase the fat % and yield in milk of sheep especially at the rate of 4% of addition.

Passive Non-Destructive Assay (PNDA) gamma-spectroscopic method is employed for nuclear material verification. The investigated materials are natural (NU) and low enriched uranium (LEU) in the form of uranium dioxide (UO 2 ) pellets and powder, respectively. A high-resolution gamma-ray spectrometer based on HPGe detector and associated electronics is used for the measurement. The spectrometer efficiency was measured experimentally using the intrinsic self-calibration method taking into account the necessary correction factors. Sample isotopic fractions were obtained using two methods; that based on the measurement of the count rate of 185.7 keV gamma line of 235 U and 1001 keV gamma line of 234m Pa ( 238 U) employing the intrinsic self-calibration technique to calculate the activity ratio of 235 U/ 238 U. The other method is based on uranium activity ratio measurements without efficiency corrections by choosing two gamma-rays close enough in energy, one related to 235 U (84.2 keV gamma line of 231 Th) and the other to 238 U (63.3 keV gamma line of 234 Th). Samples were characterized by calculating uranium isotopic mass, uranium isotopic activity ratio, total uranium content and enrichment. Special attention was given at calculating absolute error of the measured quantities, as well as the statistical behavior of the measured data in terms of the well known statistical quantities. The experimental results showed good agreement with calculated data.

In liquefied natural gas (LNG) process production, one of the important units is heavy hydrocarbon removal unit to prevent freezing during liquefaction. For small scale of LNG plant, this unit is usually integrated with main heat exchanger. Feed is obtained from main heat exchanger then flows to separator to separate liquid from gas. The separator operating condition is called as Midpoint condition. Selecting Midpoint conditions have impact to light hydrocarbon losses, Specific Brake Horse Power (SBHP) process, and heating value of LNG. Hence understanding of selecting this condition and its effect to light hydrocarbon losses, SBHP process, and HHV of LNG will help to design more efficient LNG plant. According to study, the lower of Mid-Point temperature will result in lower SBHP, lower of light hydrocarbon losses, and increase LNG of HHV value. Meanwhile, the higher Mid-Point pressure will result in lower SBHP, higher light hydrocarbon losses, and lower LNG of HHV value. The change of Mid-Point pressures have more impact to light hydrocarbon losses than SBHP process.

Objective To document the response of two patients with severe recurrent laryngeal papillomatosis following treatment with intralesional cidofovir in conjunction with carbon-dioxide laser evaporation. Setting Tertiary referral centre. Methods Retrospective review of treatment of two patients followed up over a 12-month period. Intervention Microlaryngoscopy and carbon-dioxide laser evaporation of lesions followed by intralesional injection of cidofovir. Outcome measures Photodocumentation and descriptive statistical representation of intervals between endoscopic treatment. The disease was staged according to severity on endoscopy. Results Initially, both patients showed a marked improvement of disease. However, the disease relapsed to a significant extent. Overall, there was no demonstrable change in the frequency of required endoscopies despite subjective improvement of the airway. Conclusion Cidofovir may be of some benefit in the management of recurrent respiratory papillomatosis, but further studies are still required.

Several newnaphtho[2′,1′:5,6]pyrano[2,3-d ]pyrimidineshave been synthesized via hydrazinolysis of a2-ethoxymethylideneaminonaphtho[1,2-b ]pyran;polysubstitutedpyrano[3,2-e ][1,2,4]triazolo[1,5-c ]pyrimidineshave also been prepared.

The quality of rendered leaf fat from mature breeder fowl which contained varying amounts of tocopherol due to in vivo dietary supplementation or due to direct in vitro addition was investigated. Treatments were dietary supplementation with d-alpha-tocopheryl acetate at levels of 0, 0.025, 0.050, 0.075 and 0.100% (0 to 1360 I.U./kg. feed) for 3 weeks pre-slaughter and in vitro d-alpha-tocopherol addition of 0, 10.74, 21.48, 32.22 and 42.96 μg./ml. of rendered fat (0 to 6.4 I.U./100 ml. fat) of fowl fed 3 weeks on a diet containing no tocopherol supplementation. Parameters used to estimate fat quality included AOM stability time, free fatty acid content, initial peroxide value, and moisture and volatile matter content. Tocopherol content of the rendered fat was also determined. Fat tocopherol content was found to be significantly related to AOM stability time (r = 0.93, P

A new method for the chemical labelling of nucleic acid with biotin to produce non-radioactive probes has been developed. NN'-Bis-(3-aminopropyl)butane-1,4-diamine (spermine) and long-chain diamino compounds (diaminohexane, diaminodecane and diaminododecane) were linked covalently to biotin and the resultant conjugates were attached to nucleic acid by using a cross-linking reagent (glutaraldehyde or diepoxyoctane). Iodoacetylation and biotinylation of the long-chain diamino compounds produced modified biotinylated conjugates that can be linked to DNA without the use of a cross-linking reagent. These types of probes attach one biotin molecule to each linker arm of spermine, diamino and iodoacetylated amino derivatives. Such probes have long linker arms separating the biotin moiety from the hybridization sites of the nucleic acid. These probes can detect 10 pg of target DNA by dot-blot hybridization.

Reaction of mucochloric and mucobromic acid with (ethoxycarbonylmethylene) triphenyl-phosphorane affords the ethyl ester of (2 E , 4 Z -4,5-dichloro- and (2 E , 4 Z ) -4, 5-dibromo-2,4-pentadienoic acid respectively; in the latter case ethyl (2 E -5-bromo-2-penten-4-ynoate is formed concomittantly.