Early petroleum chemists and the beginnings of chromatography

Summary The activities of D. T. Day (1859–1915, J. E. Gilpin (1866–1924) and C. Engler (1842–1925) connected with the adsorptive filtration of petroleum oil samples are discussed. As indicated, their methodology can be considered as precursor of the chromatographic technique; however, it should not be envisaged as the beginnings of chromatography.     

Geochemical and gamma spectrometric analysis of ores and hostrocks of the Kanawa uranium occurrence in NE Nigeria

The Kanawa mineralization is one of the numerous low grade U-occurrences in the Gubrunde horst, NE Nigeria. Eighty nine samples consisting of ore and host rocks have been analyzed for 12 elements and 3 isotopes by atomic absorption spectrometry, colorimetry and direct -spectrometric methods and the data described using multivariate statistical techniques. The results show an enhancement of U, Mn, P₂O₅, Fe₂O₃, CaO,²¹⁰Pb,²²⁶Ra and²³⁴Th in the ore zones. The element/isotopic associations (U–P₂O₅–²¹⁰Pb–²²⁶Ra–²³⁴Th), (Na₂O–K₂O–MgO), (Fe₂O₃–MnO–CaO–Cu) were established in the mineralized rhyolites, while (P₂O₅–²¹⁰Pb–²²⁶Ra–²³⁴Th), (Na₂O–K₂O–MgO–Zn) and Fe₂O₃–Mn–U) occur in the altered/unmineralized rocks. The variation in the pattern of association of Cu, U, Zn and CaO could be ascribed to their remobilization, depletion, enrichment or introduction in the ore zone by hydrothermal solutions. The elements/isotopes U, Zn, Cu, P₂O₅,²²⁶Ra,²¹⁰Pb,²³⁴Th or their ratios could in addition to Pb, Ba, Ce, Sm be used as pathfinder elements in prospecting concealed ores in NE Nigeria.     

Steroid alkaloids of the plant and animal Kingdoms

This review, which covers the literature for 1988–1996, gives new information on the occurrence of steroid alkaloids in Nature and discusses ecological and biogenetic aspects of their study.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (371) 120 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 2 pp. 131–168, March–April, 1999.     

Synthesis of metalloprotein complexes and study of the influence of metal ions on the structure of a carrier protein

The results are given of an investigation on the synthesis of protein conjugates with a number of metals differing by their valence and electronic state, and on their immunocompetence.Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 510–511, July–August, 1999.     

Neutron Activation Analysis of Bottom and Fly Oil Ash Leachates

Seven samples of oil fly and bottom ashes were leached with water using a Canadian standard test method for shake extraction of solid waste. The concentrations of 20 elements in the leachates were determined by the computerized systematic instrumental absolute neutron activation analysis. The ranges of concentrations (in ppm) found for the elements in the leachates were: Al (3–526), Ba (0.5–6), Ca (100–695), Cl (13–59), Co (1–6.3), Cr (0.2–6.6), Cs (0.03–0.4), Eu (0.003–0.01), Fe (28–690), K (42–464), La (0.3–49), Mg (214–3150), Mn (1.2–20), Na (88–4050), Sb (0.04–0.4), Sc (0.003–0.07), Sr (1.2–23), U (0.07–1), V (1.2–4540) and Zn (2.3–200). These findings were compared with the maximum concentrations allowed for these elements by Canadian regulations. The concentrations of Cr and U were found to be higher than their permissible limits on 7 occasions. The purpose of this study was to determine the background levels of different elements in oil ash leachates, in order to evaluate their potential impact on underground water.     

Spectrophotometric analysis of the sulphide-thiocyanate and cyanide-thiocyanate mixtures using the copper(II)-DPGH complex

Mixtures of sulphide-thiocyanate and cyanide-thiocyanate can be analyzed without separation using the Cu(II)-DPGH complex.Sulfide and cyanide cause a decrease in absorption that is a linear function of their concentration in the range 0.06–2 and 0.18–6 ppm, respectively. The Cu(II)-DPGH complex is extractable into chloroform in presence of thiocyanate and this is used for the Spectrophotometric determination of thiocyanate in the range 0.09–3 ppm.     

Structure and torsional flexibility of the linkage between guanine and fluorene residues in the deoxyguanosine–aminofluorene and deoxyguanosine–acetylaminofluorene carcinogenic adducts

Potential energy surfaces for rotations around two central CN bonds in N-(deoxyguanosin-8-yl)-2-acetylaminofluorene (AAF–dG) and its deacetylated derivative (AF–dG) were studied using Amber 95 molecular mechanics. Both of these adducts are known to be strong mutagens and carcinogens. New Amber 95 force field parameters were derived for the linkage connecting guanine and fluorene moieties in AAF–dG and AF–dG. For this purpose, we determined ab initio MP2/cc-pVDZ//B3-LYP/6-31G* and polarized continuum model Hartree–Fock/6-31G* potential energy surfaces of smaller model systems that included the N-methylimidazole–acetylaniline and N-methylimidazole–aniline adducts. The molecular mechanics parameters were adjusted to minimize differences between the gas-phase ab initio and molecular mechanics surfaces of these model systems. The resulting parameters were transferred to AF–dG and AAF–dG. The barrier for the rotation of the fluorene residue in AF–dG was found to be less than 2 kcal/mol. Such a small barrier renders the fluorene moiety freely rotatable at room temperature. In contrast, the fluorene rotation in AAF–dG is hindered by a significantly larger barrier of 10 kcal/mol. This barrier corresponds to conformations in which the fluorene and acetyl groups lie in the same plane, and is largely due to steric repulsion. Similarly, the coplanar arrangement of guanine and the bridging amino or acetyl groups is disfavored by 5–10 kcal/mol, with AAF–dG again being the more rigid of the two molecules. Energy minima for a rotation around a bond between guanine and the bridging nitrogen are found at ±80° in AAF–dG, and at 120° and –90° for AF–dG. Overall, the fluorene–dG linkages in AF–dG and AAF–dG adducts have significantly different equilibrium structures and torsional flexibilities. These differences may be contributing factors for the observed disparity in mutagenic effects of these adducts.Electronic Supplementary Material: Supplementary material is available in the online version of this article at Acknowledgements. This work was supported by the NSF REU grant no. CHE-0243825 to Loyola University Chicago. We thank to Tom Ellenberger and Shuchismita Dutta for providing us with their results prior to publication.     

Microdistributions of Electrolytic Alloys and Their Components

Microdistributions of Cu–Ni and Cu–Co alloys electrodeposited from pyrophosphate; Ni–Cu, from sulfate–chloride and pyrophosphate–ammonium; Cu–Zn, from pyrophosphate and cyanide; Cu–Cd, from sulfate and pyrophosphate; and Ni–Cd, Ni–Co–Cd, and Zn–Cd, from sulfate, sulfate–chloride, pyrophosphate, chloride–ammonium, and acetate electrolytes are studied. The coatings' microprofile depends on the kinetics of reduction of each component and mutual influence of electrochemical processes at the cathode. Copper accelerates and cadmium inhibits the reduction of the second component of alloys, no matter the electrolyte type, reduction kinetics, and metal nature. In antileveling conditions, the diffusion-controlled Cu reduction accelerates the reduction of the second component of alloys and ensures deposition of coatings whose microprofiles are more uniform than expected from diffusion limitations only. Depolarizing action of Cu during the Cu–Zn deposition from a cyanide electrolyte can completely neutralize differences in the rates of supply of reduced metal ions; hence a constant chemical composition of the coating over its microprofile. Inhibiting action of the diffusion-controlled Cd deposition provides for leveling properties of electrolytes from which Ni–Cd, Ni–Co–Cd, and Zn–Cd alloys are deposited; the chemical composition of these deposits is nonuniform over their microprofiles.     

Effect of the Conditions of Thermal Treatment of Molybdenum–Titanium and Vanadium–Molybdenum–Titanium Oxide Catalysts on Pore Structure Formation

The effect of the conditions of thermal treatment on the texture formation in molybdenum–titanium oxide (Mo–Ti–O) and vanadium–molybdenum–titanium oxide (V–Mo–Ti–O) catalysts was studied. It was found that the presence of MoO₃ in the Mo–Ti–O catalyst resulted in the stabilization of the surface area of anatase and in the retention of the fine pore structure upon thermal treatment because of the insertion of highly dispersed molybdenum crystallites into the aggregates of anatase crystallites, preventing from their agglomeration over a wide range of temperatures. In the presence of MoO₃ and V₂O₅ in the catalyst, anatase particles underwent agglomeration as the temperature was increased. This resulted in a more drastic decrease in the specific surface area and an increase in the pore size, as compared with binary samples, because of the formation of a thermally labile vanadium–molybdenum compound at the surface of anatase.     

Chemical synthesis and enzymatic assembly of fragments of the DNA coding immunodominant epitopes of human immunodeficiency virus

More than twenty 13- to 55-membered oligo(poly)nucleotides have been synthesized by the H-phosphonate solid-phase method in the manual variant using an original procedure. From the oligonucleotides obtained, seven DNA duplexes coding immunodominant epitopes of HIV-1 proteins have been formed: 598–609 and 737–748 gp41, 91–115 and 105–115 gag, and 940–951 pol and a number of its mutants. The ligase assembly and polymerization of the DNA duplexes obtained has been carried out. The efficiency of ligation amounted to from 60 to 90%. The possibility of their directed polymerization was determined by the flanking of the duplexes by partially completed half-sites of restrictases BamHI and XhoI.Abbreviations adopted: HIV-1 — human immunodeficiency virus, type 1; (+)-chain — the coding chain — and (–)-chain the chain complementary to the coding chain of the DNA duplex; CPG — controlled-pore glass; PAAG — polyacrylamide gel; Py — pyridine.D. I. Ivanovskii Institute of Virology, USSR Academy of Medical Sciences, Moscow. V. A. Engel'gardt Institute of Molecular Biology, USSR Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 393–399, May–June, 1990.     

Synthesis, structure, and action of some gossypol derivatives on the peroxidation of the lipids of biosubstrates

The synthesis has been effected of new gossypol derivatives using piperidino-and morpholinoethylamines. According to their PMR spectra, these substances exist in the keto-amine form. Their action on the peroxidation of lipids (POL) of various biosubstrates has been studied. Gossypol bis(piperinoethylimine) and bis(morpholinoethylimine) in concentrations of 1·10^–7–5·10^–6 mM exert a pronounced antioxidant action on human blood serum and rat brain synaptosomes. In the same concentrations, these substances suppressed the POL in enzymatic and nonenzymatic systems of the oxidation of rat liver microsomes.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Institute of Hematology and Blood Transfusion, Ministry of Health of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 707–712, September–October, 1989.     

Amino acid and fractional compositions of the protein fractions of the biomass of micromycetes and their biological value

On the basis of the results of an investigation of cellulolytically active micromycetes the full value and balanced nature of their protoplasmic proteins have been shown.Institute of Microbiology, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 41 71 29. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 385–389, May–June, 1999.     

Synthesis and structure of amino esters of menthol

The conditions for the acylation of (–)-menthol with monochloroacetyl chloride have been studied. Amino esters of (–)-menthol have been obtained by the nucleophilic replacement of the chlorine in (–)-menthol monochloroacetate by residues of secondary amines. Their properties and their mass, IR, and¹³C NMR spectra are described.Institute of Physical Organic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 728–733, November–December, 1981.     

Elasticity of the crystal-like,amorphous solid-like,and liquid-like structures in deionized suspensions of colloidal silica spheres

Elastic moduli (G) of deionized suspensions of colloidal silica spheres (diameters=45–192 nm; standard deviations of sphere size divided by the mean diameter=0.05–0.21; surface charge densities=0.33–0.94 C/cm²; volume fractions of sphere ()=0.019–0.21) have been determined by the reflection spectrum measurements in a sedimentation equilibrium and the rotatory viscometry. TheG-values are 56–460 Pa (=0.019–0.051), 330–890 Pa (0.06–0.09), and 100 Pa (0.025) for the crystal-like, amorphous solid-like, and liquid-like structures, respectively. TheG-values seem to be in the order amorphous solid-like > crystal-like > liquid-like at the same sphere concentration. The suspension structures and their elastic moduli are highly influenced by the sizes and their monodispersities of the spheres. These results support that the electrostatic intersphere repulsion and the long Debye-screening length around the spheres are important for the appearance of the suspension structures.     

Characteristic and spectroscopic properties of the Schiff-base model compounds

Two series of conjugated aromatic imines (Schiff-base model compounds) with different central groups and various side-group substitutions have been synthesized and characterized by elemental analysis, differential scanning calorimetry (DSC) technique, hydrogen nuclear magnetic resonance (¹H NMR), Fourier transform infrared (FTIR) and ultra-violet and visible light (UV–vis) spectroscopy measurements. The UV–vis absorption of solutions of these compounds in dimethylacetamid (DMA), chloroform and methanol was investigated in the optical range from 240 to 450 nm, where two distinct absorption bands: at 250–280 and 315–360 nm with the different level of absorption have been observed. The influence of compound molecular structure and polarity of solvent on the absorption spectra and the possible optical transitions have been discussed. Structure of diamines in the azomethine models fundamentally affected their spectroscopic properties and conjugation of π-electrons.     

Composition of the waxes from the production wastes of lavender and sage oils

The chemical compositions of the waxes and the wastes from the production of lavender and sage oils and also the influence of industrial treatment with hydrogen peroxide on their composition have been established.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 707–712, November–December, 1984.     

Daily dietary intake of trace elements of radiological and nutritional importance by the adult Indian population

The concentrations of eleven trace elements: Ca, Co, Cr, Cs, Fe, I,K, Se, Sr, Th and Zn were determined in total diet samples and also in individualfood materials which constitute the typical Indian diet. Instrumental neutronactivation analysis (INAA) and radiochemical neutron activation analysis (RNAA)were employed for the analysis. Whereas the elements Fe, Co, Cr, Se and Znare important from the view point of their role in nutrition, the elementsCs, K, Sr and Th are of importance in radiation protection, and Ca and I havedual importance: both in nutrition as well as in radiation protection. Basedon the analysis of twenty total diet samples, prepared as per the data onthe dietary intake pattern of four provinces of India and the data on intakepattern of an average adult Indian, the geometric mean (GM) intake of variouselements was estimated to be 0.33 g (0.2–0.67) for Ca, 16.5 µg(8.3–31.1) for Co, 52.3 µg (35.1–131) for Cr, 4.7 µg(2.79–11.8) for Cs, 94.6 µg (60.6–201) for I, 1.90 g (1.25–3.54)for K, 1.13 mg (0.78–2.97) for Sr, 0.76 µg (0.45–1.66) forTh, 15.9 mg (10.2–34.3) for Fe, 56.3 µg (27.6–105.3) forSe and 8.6 mg (5.1–16.7) for Zn. Some of the important individual foodmaterials, such as cereals, pulses, milk, vegetables etc., were also analysedfor these elements to observe the contributions of the individual food materialsto their daily dietary intake. The results of the analysis showed that inthe case of Cs, K, Sr, Th, Fe, Zn and Co, almost 50% of the daily dietaryintake of the above stated elements is contributed by cereals and pulses.In the case of Ca however, significant amount is contributed by milk and incase of I, iodised salt could make significant contribution. The data collectedso far, for Se and Cr, was not sufficient to draw any definite conclusion.     

Influence of packing of the reactants and products in solution on the volume parameters of the Diels-Alder reaction

The possible causes of a dramatic difference in the volume parameters (by up to 15–20 cm³ mol^–1) of the Diels-Alder reactions involving bulky and small reactants are discussed. The partial molar volumes of anthracene and 9,10-dihydroanthracene and the heats of their solution in six solvents were determined.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1674–1680.Original Russian Text Copyright © 2004 by Kiselev, Kashaeva, Potapova, Shikhab, Konovalov.This revised version was published online in April 2005 with a corrected cover date.     

Probing the accuracy of the isomerization energy of the 3-D morphed potential of Ar–HBr

Investigations of the lowest Σ-bending vibrations of Ar–DBr (v = 0) and Ar–HBr (v = 1) are reported using a co-axially configured submillimeter supersonic jet spectrometer. The v = 1 spectra were obtained using glow discharge excitation. Analyses of hyperfine substructure in these spectra provide accurate molecular parameters for Ar–DBr and Ar–BrD isomeric states, direct determination of their corresponding isomerization energies, and respective parameters in the v = 1 HBr stretching vibration of the Ar–HBr isotopomer. This experimental data provides a sensitive probe of the relative energies of potential minima for previously determined 3-D Ar–HBr morphed potential and compared with results from extrapolations to the CCSD(T)/CBS limit.     

Study of the structure and stability of compounds PF n,n=1–5, and their anions by the density functional method

The electronic and geometrical structure of phosphorus fluorides PF_n, n = 1–5, and their singly-charged negative ions was calculated using the density functional method. Both the ground and low-lying excited states of the two series were considered. The structural parameters of neutral radicals PF₂, PF₄, and their anions were obtained for the first time. The adiabatic and vertical electron affinities (EA) of the neutral phosphorus fluorides, and the first ionization potentials of the anions were calculated. According to the calculation results, all the phosphorus fluorides have positive EA_ad, except for PF₃, which has an EA of about zero, and requires further investigation. The dissociation energies of both the neutral and negatively charged phosphorus fluorides were calculated through different channels. All the PF_n and PF _n ^– , n = 1–5, are stable in the gaseous phase. The PF^–, PF ₂ ^– , PF ₃ ^– , and PF ₅ ^– anions have excited states which are stable with respect to both the splitting off of an outer electron and to dissociation.Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2219–2232, October, 1992.