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This paper describes an accurate method to determine esterified glycerol in the glycerides of edible fats and oils and, in general, in all triglyceride fat or oil. Esterified glycerol is released by means of a transesterification reaction with potassium hydroxide in methanol, which simultaneously produces fatty acid methyl esters. Free glycerol is oxidized selectively to formic acid and without any interference in the same environment in which the transesterification reaction occurs by the addition of periodate. The formic acid produced is then potentiometrically titrated using an acid–base reaction. By knowing the acidic composition and the distribution of the glycerol between triglycerides, diglycerides and monoglycerides, the determination of glycerol also makes it possible to evaluate the content of glycerides present in the fats. The most accurate glyceride determination was obtained by suitably combining the determination of bound glycerol and the distribution of fatty acids obtained by means of gas chromatographic analysis. With little modifications, the proposed method also makes it possible to successfully analyse edible fat in terms of glycerol content in aqueous containing matrixes.

The nicotine content of the tobacco powder completely degrades in one week when it is added to a non manured soil. If some organic manure is added to the soil so as to sensibly increase the microbial flora, then nicotine degrades in less than twenty-four hours. In sterilized soil nicotine content is constant over the time because of the total absence of microorganism. In the determination of the nicotine in the soil, accurate analytical results can be obtained by adding methanol to the soil sample at the moment of the sampling. Methanol degrades the enzymatic systems causing a soil sterilization and avoids, therefore, the degradation of the alkaloid. The extracted nicotine is analyzed by means of high performance liquid chromatography in a rapid and accurate manner.

The interference of triglycerides in the analysis of sterols and their esters in fats can be eliminated by transesterification of the sample dissolved in n-hexane with a solution of sodium hydroxide 2 mol/L. Since the analytes are distributed equally in n-hexane and in methanol, better results can be obtained by accurate measurements of the volumes, and processing the standards as the samples. Triglycerides and steryl esters are transesterified quantitatively by a solution of sodium hydroxide 2 mol/L using diethyl ether as solvent. At 40°C, ten minutes are sufficient to complete the reaction. The sterols are determined in fats using a mass spectrometer detector, at concentrations as low as 5 mg/Kg. Using FID, it was possible to analyze sterols present in concentrations higher than 100 mg/Kg.

A simpler and faster procedure than the official one described in document IV of European Economic Community Regulation 183/93 is proposed. The wax ester fraction is isolated from triglycerides using a commercially available silica gel column and carbon tetrachloride as eluent. The recovered wax ester fraction, with the addition of a suitable internal standard solution, is analyzed by gas chromatography. A column with a 65% phenyl methyl silicone stationary phase allows a satisfying separation of wax ester fraction in comparison with both a steryl ester and a light fraction eluted before the internal standard. Furthermore, also the single components of the wax ester fraction are suitably separated.

In this paper we present an innovative device designed and constructed to improve the fumigation process for stored foodstuffs with the use of phosphine gas in sealed chambers. The device allowed a considerable reduction in phosphine production time (from about 5 to 7 days for traditional systems to 2 days for the equipment considered), maintaining the system below the inflammability threshold, and at the same time achieving the total exhaustion of aluminum (or magnesium) phosphide so as to avoid toxic residues at the end of the process. With the standard device currently available on the market, after the normal 5–7 day fumigating period, the powder residue contains as much as 1–2% (w/w) of phosphide. Thus the residues, according to current legislation, have to be considered toxic and harmful. To overcome this disadvantage, appropriate modifications were made to the cylindrical tray used for the fumigation process: a nebulizer was installed, which has the function of increasing the moisture of the air spreading around the phosphide pellets and allowing a more rapid reaction with phosphide. Moreover, the cylindrical tray was also heated by means of an electrical resistance, and temperature was checked by a thermostat, so as to always obtain the same efficiency, independently of outside temperature, for both hot and cold periods, since reaction speed depends on the system temperature considered. In addition, a control device for air saturation allows condensation processes to be avoided. Using the modified cylindrical tray we performed tests to determine the best values of humidity and temperature for the process concerned, avoiding phosphine concentrations that might result in a fire hazard, and the remixing of phosphide pellets inside the cylindrical tray. Our experimental data allowed us to obtain a mathematical model used to gain an insight into the process in question.

This article gives a description of the setup in a laboratory of a pilot system to reduce phosphine following the smoking process of foodstuffs. At present, this fumigant is released into the atmosphere and causes serious damage to the environment due to its transformation into aggressive compounds. However, phosphine may prove a good alternative to methyl bromide, which will legally be used as a fumigant until the year 2002, provided it is made inert after the smoking process and transformed into nontoxic and easily disposable substances. Oxidant solutions containing potassium permanganate or potassium bichromate in suitable concentrations proved moderately effective in reducing phosphine. The addition of traces of silver nitrate as a catalyst to the oxidant solutions increased the efficiency in reducing the fumigant, although not completely. Thus it was necessary to use a recycling system to decontaminate air from phosphine, as such an apparatus ensures the complete reduction of phosphine. The mathematical function describing how the concentration of phosphine varies in the smoking chamber also makes it possible to estimate the time necessary to reduce a phosphine concentration from any initial value to a fixed final value.

Background Truvada, a fixed-dose combination of antiretroviral drugs (emtricitabine and tenofovir fumarate) indicated for HIV-1, was the 12th most expensive drug prescribed in Piedmont during 2009–2010, with a growth of 12%. Since July 2011 the School of Hospital Pharmacy in Turin has developed a two-year pharmacoeconomic project regarding high-cost drugs. Purpose To provide to the decision-makers with a management tool to evaluate the treatment costs of HIV patients. Materials and Methods The legislation and articles in epidemiology and pharmacoeconomic journals were reviewed. Drummond’s Weighted Checklist method was used to evaluate the pharmacoeconomic articles. A Budget Impact model, based only on the drug costs, was built. The treatment-naive population (290) was extrapolated from the incidence data in Piedmont in 2010. The treatment options relied on the US Department of Health and Human Services guidelines and on the pharmacoeconomic studies. The model suggested a combination of Truvada with: i) efavirenz (NNRTI, Sustiva), ii) atazanavir (PI, Reyataz)+ritonavir (PI booster, Norvir); iii) darunavir (PI, Prezista)+ritonavir (PI booster, Norvir). Results The daily treatment cost for a treatment-naive patient varies from €21.78 to €30.64, while the annual expenditure varies from €7,949.17 to €11,184.45. The Budget Impact was calculated assuming that the 290 new HIV cases had been treated for one year with one of the therapeutic strategies provided. The variation in comparison with association i) were respectively +24.64% for combination ii) and +40.70% for combination iii). Treatment iii) was the most expensive (€324,3491.37) and increased the annual expenditure by 40.70% (€938,233.23) as compared with treatment i) (€2305,258.14). Conclusions The Budget Impact analysis will be used to perform pre-assessments of expenditure in order to set up health care programmes for the allocation of the economic resources. A pharmacoeconomic analysis of cost-effectiveness will be performed between the associations Truvada + Reyataz and Truvada + Sustiva. No conflict of interest.

A simple method for the determination of trace amounts of CN− and/or SCN− in water is suggested. The method is based on the prior transformation of CN− or SCN− into HCN; the HCN is separated from the aqueous sample by the headspace technique, analysed by gas-solid chromatography and selectively detected with a nitrogen-phosphorus detector. Cyanides and/or thiocyanates at concentrations between 0.01 and 100 ppm can be detected with a linear response. The procedure has been used for the determination of CN− in coke-oven water and in coke-oven waste effluent.

Comparaison des R F d'une serie d'alcanes, alcools aromatiques, avec N 2 O, freon-22, propene, propane, butane, hexane

The critical factor in the preparation of glass capillary columns is the coating of the inner wall with stationary phase. Difficulty is usually met when a very polar compound has to be coated and statisfactory results are obtained only when the inside surface is roughened. Though a number of devices have been suggested, reproducible results are seldom obtained. The outstanding properties of graphitized carbon black (GCB) permit the formation of an ideal precoating of a glass capillary upon which any stationary phase can be applied. The precoating is carried out by flowing through the capillary a colloidal solution of GCB obtained by exposing a 1% solution in methylene chloride to an ultrasonic generator. A colloidal solution is obtained by means of this treatment, which after introduction into the capillary and evaporation of the solvent leaves a layer, which strongly adheres to the surface and is not even removed by washing with polar and non polar solvents. After washing the graphite surface a new stationary phase can be coated on it. A great variety of columns of different polarity can be prepared such as SP 1000, apiezon, carbowax, SE 30 and SE 52, and their characteristics are evaluated. The use of a colloidal solution prepared by ultrasonic means can be extended also to the preparation of gas solid columns.

Les cyanhydrines formees par reaction avec le cyanure sont analysees par chromatographie gaz solide et detectees selectivement avec un detecteur azote phosphore

In glacial marine sediments from the St. Lawrence estuary, iron varies between 1.32 and 5.42%, manganese between 0.043 and 0.28%, and titanium between 0.31 and 0.64%. The regional distributions of these elements are related to sediment texture. Analyses of individual sediment size-fractions show that Fe, Mn, and Ti concentrations generally increase with decreasing grain size. Variations in elemental ratios between the different grades suggests that not all of the Fe and Mn is located in detrital silicate minerals. Dithionite extraction of selected sediments resulted in preferential dissolution of 3–16% of the total iron, presumably that derived from amorphous and crystalline iron oxides and from sorbed material.Hydroxylamine–hydrochloride removed 5–60% of the total manganese, presumably that derived from exchangeable Mn, easily reducible Mn oxides, and sorbed Mn material. The soluble fraction is highest in freshly deposited pelites from the center of the estuary. Soluble Fe and Mn occur as oxide films on the particles deposited from suspension, and the amount held depends on rate of deposition and on the physicochemical conditions in the waters and in the sediments. In contrast, Ti occurs in detrital minerals and accumulates at the same rate as detrital sedimentary material. It is unaffected by environmental changes. This investigation shows that, despite the derivation of the sedimentary material from the Canadian Shield predominantly by nonchemical erosional processes, small but significant chemical modification of iron- and manganese-bearing material is taking place in response to present physicochemical conditions.

A gas-chromatographic procedure has been used for the determination of CN - in coke-oven water and in coke-oven waste effluent into the sea. It is based on the treatment of the sample with bromine water and on the direct selective detection of CNBr by gas-solid chromatography. The procedure avoids the preliminary treatments of the sample described in the “Standard Methods” (APHA, 1971) being much faster and more reliable than the previously suggested method.

Pivalyl chloride and benzoyl chloride are utilized as reagents for the N-terminal analysis of polypeptide chains. Pivalyl and benzoyl derivatives obtained are analyzed by gas-liquid chromatography using glass capillary columns. The chromatographic resolution of the most common amino acid derivatives allows a quantitative estimation of the N-terminal residues even in the case of complicated peptide mixtures.

A homogeneous cerebroside was isolated from a strain of Fusicoccum amygdali Del., a fungus pathogenic to almond and peach. Chemical degradations, together with extensive application of nuclear magnetic resonance and mass spectrometry techniques, led to elucidation of its structure. This corresponds to N-2′- hydroxy -3 ′-trans- octadecenoyl -1-O-β- d - glucosyl -9- methyl -cis-4 , x-8-sphingadienine.