Analysis about Stability of a Slope

Based on the engineering geological conditions of an artificial slope is analyzed using a combination of numerical simulation, the slope ratio method and other methods, the slope stability was evaluated, It has a certain reference to artificial slope stability evaluation that similar to a combination of soil and rock.

Solvent Extraction and Spectrophotometric Determination of Uranium (VI) Using 2,2′-[1,2-phenylenebis(nitrilomethylidene)]bisphenol (BSOPD) as an Analytical Reagent

2,2'-[1,2-phenylenebis(nitrilomethylidene)]bisphenol (BSOPD) is synthesized in the laboratoryand characterized by NMR, IR and elemental analysis for its purity. This reagent forms a yellowcomplex with U(VI) which can be quantitatively extracted into chloroform at pH 10. This complex inchloroform shows an intense absorption peak at 413.0 nm. It is observed that Beer’s law is obeyed inthe range of 2.0-10.0 ppm of metal solution. It gives a linear and reproducible graph under appropriateconditions, the complex having a molar absorptivity of 3.69 x 104 L mol-1·cm-1. Sandell’s sensitivitycalculated was found to be 4.4 x 10-3μg·cm-2. Nature of the extracted complex, determined by Job’scontinuous variation method, Slope ratio method and Mole ratio method shows that the compositionof U(VI) : BSOPD complex is 1:4. Interference by various ions is studied and masking agents usedwhere required. The proposed method has been applied for the determination of U(VI) in monazite sand and synthetic samples. The results of the analysis are found to be comparable with those obtained by standard method.

FORMULA ESTABLISHMENT OF COLORLESS Pb(II) COMPLEX WITH N-BENZOYL-N-PHENYL HYDROXYLAMINE (BPA) USING ATOMIC ABSORPTION SPECTROSCOPY

A new method for determination of stoichiometry of colorless complexes by using atomic absorption spectrophotometric technique in continuous variation method and slope ratio method was described here. This method can be used in same manner as that of mole ratio method and slope ratio method. In this method atomic absorption spectroscopy was used instead of UV-Vis spectrophotometry. Atomic absorption spectrophotometric technique is superior to UV-Vis spectrophotometry as it can be applied to colorless soluble complexes. Pb(II) and n-benzoyl-n-phenyl hydroxylamine react to form colorless complex at pH 6.5, which can be easily determined by this method. It was found that Pb(II) forms 1:2 complex with n-benzoyl-n-phenyl hydroxylamine and is quantitatively extracted back to aqueous solution for AAS analysis.

Reversed-Phase Ultra-Performance Liquid Chromatographic Method Development and Validation for Determination of Impurities Related to Torsemide Tablets

A simple RP-ultra-performance LC method was developed and validated for determination of impurities related to torsemide tablets. The rapid method provided adequate separation of all known related impurities and degradation products. Separation was achieved on a Zorbax SB-C18 column (50 × 4.6 mm id, 1.8 μm particle size) with binary gradient elution, and detection was performed at 288 nm. The drug product was subjected to oxidative, hydrolytic, photolytic, and thermal stress conditions to prove the specificity of the proposed method. The linearity and recovery were investigated for known impurities in the range of 0.025 to 1.0%, with respect to the drug concentration in the prepared sample. The linearity of the calibration curve for each of the impurities and torsemide was found to be very good (r2 > 0.999). Relative response factors for each of the known impurities were established by the slope ratio method from the linearity study.

Bioavailability of selenium from raw or cured selenomethionine-enriched fillets of Atlantic salmon (Salmo salar) assessed in selenium-deficient rats

The bioavailability of Se from raw and cured selenomethionine-enriched (Se-enriched) salmon fillets was assessed in Se-deficient male albino rats (Mol: Wist). A low-Se Torula yeast feed was supplemented with 0, 50, 100, 150 or 200 μg Se/kg as sodium selenite or as Se from raw or cured Se-enriched salmon. The diets were fed to weanling rats for 10 and 30 d. Bioavailability of Se was assessed by metabolic balance, Se accumulation in femur, muscle, liver and plasma, and induction of Se-dependent glutathione peroxidase (EC 1·11·1.9; GSHpx) in plasma as response parameters. Except for the metabolic balance results, the slope-ratio method was used when calculating Se bioavailability from raw or cured Se-enriched fish fillets (test food) relative to sodium selenite (standard). The data for fractional apparent absorption and fractional retention showed differences (P<0·05) among all three Se sources in the order raw salmon > cured salmon > selenite. At 10 d, Se from raw and cured Se-enriched fish fillets tended to be more bioavailable than selenite. This was supported by the observations for Se accumulation in femur and muscle and induction of GSHpx activity. At 30 d, all response parameters showed a higher bioavailability of Se from raw and cured Se-enriched fish fillets compared with selenite. Differences (P<0·05) in Se accumulation in muscle at 10 and 30 d, and differences (P<0·05) in fractional apparent absorption and fractional retention suggested that curing salmon altered the utilisation of Se. The experimental results showed that enrichment of fish fillets with selenomethionine yields fillets with high Se bioavailability.

Novel Quantitative Assays for Estimating the Antimicrobial Activity of Fresh Garlic Juice†,‡

Novel agar diffusion and broth dilution assays were developed for quantitatively estimating the antimicrobial activity of fresh garlic juice. Bacteria found to be inhibited by garlic juice in agar diffusion assay included two gram-positive and five gram-negative species. Leuconostoc mesenteroides was not inhibited. Escherichia coli B-103 (HB101, with pJH101, ampicillin resistant, 100 μg ml−1) was inhibited and chosen as the standard culture for quantitative assays. The agar diffusion assay was based on the slope ratio method, where the slope of dose response for garlic juice was divided by the slope of dose response for methylmethane thiosulfonate (MMTSO2). Juice from fresh garlic varied in activity between 1.76 and 2.31 μg of MMTSO2 per mg of garlic juice. The activity of juice decreased during 11 months of storage of garlic cloves at 5°C from 2.31 to less than 0.1 μg of MMTSO2 per mg of juice. The broth dilution assay also used the E. coli B-103 culture, which permitted selective enumeration of this bacterium when 100 μg ml−1 of ampicillin was incorporated into the enumerating agar. Selective enumeration was essential since the garlic juice was not sterile and, thus, contained natural flora. Growth of E. coli was unaffected by 0.1%, delayed by 0.25%, and completely inhibited at 0.5 and 2% garlic juice in broth during 24 h of incubation at 37°C. The minimum inhibition concentration of garlic juice by broth dilution assay was, thus, estimated to be 0.5%, which is equivalent to 3.46 μg of MMTSO2 per mg of garlic juice by the agar diffusion assay.