Distilled Off Research Articles

Energy Storage and Heat to Power Conversion and with Non-Aqueous All Copper Redox Flow Batteries

In this presentation we will describe a new approach for conversion of heat into chemical energy, stored in a battery. A thermo-electrochemical system with a redox flow battery (RFB) is proposed to allow the conversion of heat at relatively low temperature into chemical energy. The electroactive species of the battery are copper ions in an organic solvent mixture containing acetonitrile as a complexing agent, resulting in a cell voltage of 1.2 V. Water is avoided because its presence reduces considerably the cell voltage. This non-aqueous hybrid redox flow battery can be utilized for electrochemical energy storage, and the efficiency of the system for this purpose will be discussed. More interestingly, the battery can be also charged with heat. For thermal charging, the Cu(I) complex with acetonitrile can be destabilized by a heat source of around 170°C (or more). At these temperatures all the acetonitrile is distilled off and the destabilized Cu(I) species disproportionates into metallic Cu and Cu(II) species dissolved in the electrolyte. Following separation and recovery of the distilled acetonitrile the system can be discharged again. Now the chemical energy stored in the battery be converted into electricity with the Cu oxidation and Cu(II) reduction in the different half cells. In this presentation we shall discuss the electrochemistry of copper in acetonitrile and propylene carbonate mixtures, the thermodynamic properties of the copper electrolytes as well as the heat required for the thermal regeneration, as has been evaluated by differential scanning calorimetry. Additionally, we will present our latest results with non-aqueous copper slurry electrolytes and report the efficiency of the full cycling consisting of electrochemical discharge followed by thermal charge. The theoretical efficiency of the heat-to-power conversion has been evaluated as 30%, close to the Carnot efficiency with T cold at 298 K and T hot at 443 K. The losses of the cell will decrease the practical efficiency, so further improvement of the flow battery is required.

Особенности строения липотейхоевых кислот бифидобактерий по данным ТСХ и ИК-ФТ

Липотейхоевые кислоты (ЛТК) клеточной стенки представителей рода Bifidobacterium проанализированы методом ТСХ и ИК-ФТ. Экстракцию ЛТК из бактериальных клеток разных видов осуществляли смесью хлороформ : гексан. Установлены видовые отличия в хроматографических и спектральных характеристиках ЛТК бифидобактерий. Так, ЛТК B. bifidum характеризуются относительно высоким содержанием полиеновых фрагментов и остатков фосфорной кислоты. В свою очередь ЛТК B. breve отличаются низким содержанием непредельных фрагментов. Для B. longum характерно наличие в структуре ЛТК остатков фосфорной кислоты с тремя электроотрицательными заместителями. Установлены особенности разделения ЛТК разных видов бифидобактерий в условиях ТСХ. Показана возможность сравнительного анализа ЛТК грамположительных бактерий в режиме ТСХ с последующим экстрагированием хроматографических зон и изучением в режиме ИК-ФТ

Formation of benzenediols upon electron-beam distillation of lignin mixtures with alkanes

In the process of the electron-beam distillation of lignin, its conversion into benzenediols increases in the presence of alkanes in the irradiated sample. An increase in the yield of benzenediols is accompanied by a decrease in the fractions of guaiacol, creosol, ethylguaiacol, and vinylguaiacol in the tar distilled off. It has been noted that alkanes serve as an additional source of atomic hydrogen and alkyl radicals, which, in turn, play a key role in the formation of benzenediols. In the presence of alkanes in the irradiated sample, guaiacol can be the main precursor of catechols; the proportion of guaiacol in the tar is almost three times below that in the case of distillation of individual lignin. It has been hypothesized that the chain decomposition of lignin can occur with the participation of •H and •CH3 radicals.

Three-Component Reaction of Benzothiazole, Acetylenic Esters, Phenoles; Synthesis of Dialkyl 2-benzo[d]thiazol Derivatives Under Grinding.

Due to biological activity of a significant number of compounds containing benzothiazole ring system and in continuation of our interest in developing new environmentally benign methods for the synthesis of heterocyclic compounds by MCRs in this study we performed an efficient three-component from benzothiazole, acetylenic esters and hydroxyl aromatics compounds to synthesize of 2- benzothiazole derivatives in high yield. IR spectra were recorded using an FTIR apparatus. Melting points measured on an Electrothermal 9100 apparatus. Spectra were obtained in solution of CDCl3 using TMS as internal standard. Elemental analyses were carried out using a Heracus CHN-O- Rapid analyzer. A mixture of benzothiazole, dimethyl acetylenedicarboxylate and phenol were placed in a mortar. The mixture was ground with a mortar and pestle at room temperature for 12 min. After completion of the reaction, as indicated by TLC (ethyl acetate: n-hexane, 1: 3), the solvent was distilled off under reduced pressure and the residue was crystallized from diethyl ether. Treatment of benzothiazole and dialkyl acetylenedicarboxylates in presence of resorcinol and β-naphthol led to products 4 (dialkyl (E)-2-(2-(2-hydroxyphenyl)benzo[d]thiazol-3(2H)-yl-3- methylbut-2-enedioate), while we observed two isomer (Z) and (E) configurations (major and minor) in nearly 70:30 ratio when the reaction was repeated in presence of 8-hydroxy quinolone and DMAD. Also when we examined 2-nitro phenol, 4-nitrophenol, and 4-hydroxy quinoline, only one product 5 was obtained. This indicates that the reaction proceeds efficiently with electron-releasing substituted phenols. The reaction between benzothiazole and dialkyl acetylenedicarboxylates in the presence of some phenols without electron-withdraw substitution, presents a novel, one-pot, clean, convenient, simple and inexpensive approach into the synthesis of 2-benzothiazole derivatives of potential synthetic and pharmacologically interest. This procedure carries significant advantages because of the minimization of labor, time, and cost.

Upgrading of palm oil renewable diesel through hydroisomerization and formulation of an optimal blend

Renewable diesel is the best alternative to replace biodiesel due to its improved properties, but like biodiesel, renewable diesel has poor cold-flow properties. The hydroisomerization process improves the pour and cloud points of renewable diesel, but it worsens the cetane number and the flame point, both are regulated by international standards. In this work, desoxygenated palm oil (HDO) was produced in high yield (82wt%) using a sulphided NiMo/Al2O3 catalyst. Then, HDO was hydroisomerized at 50bar and 350°C, under hydrogen, with a Pt/SAPO11 catalyst, obtaining an isomer yield of 81%. TPR and TPO analyses showed that this catalyst can be reversibly reduced/oxidized at 155–160°C, therefore, it was completely reduced at the reaction conditions. Characterization of the isomerized product (i-HDO) showed a beneficial effect on cold-flow properties but an adverse effect on flash point, distillation range and cetane index due to light hydrocarbons formed during hydroisomerization. Light hydrocarbons (<C14, 7vol%) in i-HDO were distilled off at 180°C to tune the flash point and the distillation range. The hydroisomerized and distilled product (i-HDOd) was blended with HDO to determine the required hydroisomerization level to meet the cold-flow regulations. The optimal blend consisted of 71% i-HDOd and 29% HDO and it has a cetane index of 92.4, pour point of 2.8°C, flash point of 82°C, distillation range of 225–321°C and heating value of 47.3MJ/kg.

Phenolic products of the high-temperature radiolysis of lignin

The products of the radiation-stimulated dry distillation of coniferous hydrolytic lignin at a residual pressure of 1–5 torr have been obtained and analyzed. The tar distilled off under irradiation conditions predominantly contains phenols, including about 33% benzenediols. Among the benzenediols, the fraction of catechols is 69%. Phenoxyl radicals are considered to be direct precursors of the phenolic products. It has been found that the formation of benzenediols can be due to the rupture of the ether bond in the methoxy group. Among secondary processes, the reactions of the addition of •H and •CH3 radicals to the benzene ring have been considered.

Semicoking of Kansko-Achinsk lignite and applications of tar fractions

The semicoking of regular lignite from the Berezovsk field in Kansko-Achinsk Basin (moisture content 1.6–19.6 wt %) at 450–550°C in a reactor with solid heat carrier is studied. The products are semicoke (up to 68.1%), tar (up to 9.5%), gas (up to 31.9%), and pyrogenetic water. The composition of the semicoking gas is quantitatively determined. Its main components are hydrogen (up to 71.7%) and methane (up to 17.2%). The heat of combustion of the semicoking gas is 12.39–16.25 MJ/m3. The yield of phenolic fractions in the semicoking tar, consisting of phenol and its alkyl derivatives with one or two short substituents (C1–C3), is 10.5–14.6%. After hydraulic purification of the gasoline fraction in the semicoking tar (below 180°C), gasoline with octane rating 75.8 (by the motor method) is obtained. It consists of aromatic, saturated, and unsaturated hydrocarbons (C5–C8). The diesel fuel derived from tar fractions distilled off at temperatures up to 350°C are of good quality, except for their low cetane rating. The high-boiling tar fractions may be used to produce lignite pitch and pitch coke. The semicoke obtained is a very effective reducing agent in the production of phosphorus. It may also be used as a lean additive in coking batch and as a component in enriched domestic coal briquets.

Gallium isopropoxide: Synthesis, properties, “coordination polymerism”. New pentanuclear gallium oxoisopropoxochloride

Conditions for the synthesis of gallium isopropoxide (I) by anodic dissolution of the metal in i-PrOH (in the presence of Bu4NBr supporting electrolyte) and by exchange reaction of GaCl3 with i-PrONa were studied. In the latter case, the crude product was a waxy substance (II) infinitely soluble in the alcohol and hydrocarbons and containing 12–30% Cl, which cannot be removed by adding an excess of i-PrONa due to the formation of insoluble NaGa(OPr-i)4. During 1.5–2 months, II is solidified to give non-melting nonvolatile amorphous product (III) poorly soluble in the alcohol. Upon heat treatment of II in vacuum, compound I is distilled off as an oily liquid consisting, according to mass spectrometry, of [Ga(OPr-i)3]2 dimer molecules. It can be retained for a long period of time in the presence of the [Ga(OPr-i)3]4 tetramer crystals. The existence of oligomeric molecules of different size up to polymers (“coordination polymerism”) in the materials is related to the possibility of tetrahedral or octahedral coordination of the metal atom. From concentrated solutions of components, the oxoalkoxochloride [Ga5(µ5-O)(µ-OPr-i)8Cl5] (IV) is crystallized. Its molecule is a flattened tetragonal pyramid. The equatorial plane formed by four gallium atoms has the µ5-O group at the center. The axial Ga atom has an octahedral coordination. All eight sides of the pyramid are drawn together by the µ-OPr-i groups, and the chlorine atoms occupy the terminal positions. (CIF file CCDC no. 693282.)

One-Step Synthesis of Racemic 6-Methyloctan-3-One, an Alarm Pheromone Component of Ants of the Genus Crematogaster

6-Methyloctan-3-one (1) was identified as a component of the alarm pheromone of ants of the genus Crematogaster [1]. Several syntheses of this compound as the racemate and an enantiomer are known [2–6]. However, many of them involve several steps and most are labor-intensive and require costly starting materials. We developed a convenient and effective synthetic pathway for a racemic analog of 1 that was based on our recently proposed regioselective carbonylation of 1-alkenes using Et2Zn and TaCl5 catalyst [7]. The reaction of but-1-ene with Et2Zn in the presence of TaCl5 (Et2Zn–but-1-ene–TaCl5 = 110:100:5; Et2Zn concentration 1.0 mmol/mL in hexane, 20°C, 5 h) formed organozinc compound 2. For this, hexane (20 mL) was cooled to –15°C and treated with but-1-ene (2.25 ml, 20 mmol) cooled to –30°C. Then, the solution was cooled to –15–20°C, treated with Et2Zn (2.25 mL, 22 mmol) and TaCl5 (0.4 g, 1 mmol), heated gradually to room temperature, stirred for 5 h, cooled to –5°C, and treated dropwise with propionylchloride (3, 1.74 mL, 20 mmol) in hexane. All these operations were performed under a dry Ar atmosphere. The resulting reaction mixture was stirred for 2 h and treated with aqueous HCl solution (10%). The resulting 1 was extracted by Et2O (3 50 mL). The extracts were dried over anhydrous MgSO4. The solvent was distilled off. The residue was chromatographed (SiO2, hexane) to afford 1 (2.69 g, 99% pure) in 95% yield based on 3 (Scheme 1). The structure of 1 was proven using IR, PMR, and 13C NMR spectral methods and GC-MS in addition to comparison with an authentic sample [6].

SYNTHESIS AND EVALUATION OF SOME NEWLY TRIAZOLYLINDOLE DERIVATIVES FOR ANTIFUNGAL ACTIVITY

A series of novel 2 - ((2 - (phenyl/4 - chl orophenyl) - 1 - ((4 - ((Z) - 1 - (substitutedphenyl)ethylideneamino) - 5 - mercapto - 4H - 1,2,4 - triazol - 3 - yl)methyl) - 1H - indol - 3 - yl)methyleneamino)benzoic acid (9 - 16) were synthesized by treating 2 - ((1 - ((4 - amino - 5 - mercapto - 4H - 1,2,4 - triazol - 3 - yl)methyl) - 2 - (phenyl/4 - chloroph enyl) - 1H - indol - 3 - yl)methyleneamino)benzoic acid (7 - 8) with various substituted acetophenone. The structure of the compounds was characterized by IR and 1 General procedure for preparation of 2 - ((2 - phenyl/4 - chlorophenyl - 1H - indol - 3 - yl)methyleneamino)benzoic acid (1 - 2) A mixture of 2 - phenyl/4 - chlorophenyl - 1H - indole - 3 - carbaldehydes (0.1 mol) and anthranilic acid (0.1 mol) in absolute ethanol (90 ml) cont aining few drops of glacial acetic acid was refluxed for 28 h and excess of solvent was distilled off. The solids thus obtained were filtered, dried and re crystallized from ethyl acetate to yield compounds 1 - 2 2 - ((1 - (2 - ethoxy - 2 - oxoethyl) - 2 - (phenyl/4 - chlo rophenyl) - 1H - indol - 3 - yl)methyleneamino)benzoic acid (3 - 4) A mixture of compounds 1 - 2 (0.1 mol), ethyl chloroacetate (0.1 mol), anhydrous acetone (90 ml) and NaOH (16 g) was heated under reflux of 22 h. The reaction mixtures were cooled, wash with excess of water, filtered and dried, again washed with ethanol and re c r ystallized from appropriate solvent to yield compounds 3 - 4. 2 - ((1 - (2 - hydrazinyl - 2 - oxoethyl) - 2 - phenyl - 1H - indol - 3 - yl)methyleneamino)benzoic acid (5 - 6) A mixture of compounds 3 - 4 (0.1 mol) and hy drazine hydrate (0.2 mol) in absolute ethanol (80 ml) was refluxed for 18 h then cooled and poured on crushed ice and separated. The solids were filtered, washed with cold water, dried and re c r ystallized from appropriate solvent to yield compounds 5 - 6. 2 - ((1 - ((4 - amino - 5 - mercapto - 4H - 1,2,4 - triazol - 3 - yl)methyl) - 2 - (phenyl/4 - chlorophenyl) - 1H - indol - 3 - yl)methylene amino)benzoic acid (7 - 8) To the ice cold mixture of compounds 5 - 6 (0.1 mol) and KOH (0.4 mol) in dry ethanol (90 ml), carbon disulphide (0.1 mol) was a dded with magnetic stirring. The reaction mixtures were stirred further at room temperature for 24 h. The separated solids were filtered washed with dry ether and dried. These were further magnetically stirred with hydrazine hydrate (0.15 mol) on boiling w ater bath for 4 h till the evolution of H 2 S ceased. The reaction mixtures were poured into ice - cold water then filtered, washed with water, dried and re crystallized from acetic acid to yield compounds 7 - 8.

Chemical Constituents of Eremurus anisopterus

The genus Eremurus (Liliaceae) comprises about 50 species growing mainly in central and western Asia. Four species of this genus are found in China [1]. The plant E. anisopterus (Kar. et Kir.) Regel is broadly distributed in western China. Its roots are used to treat rheumatism and physical weakness [2]. We investigated the air-dried aerial part of E. anisopterus collected in Xinjiang Autonomous Region (Shawan County in July 2012) of the PRC. Ground raw material (3 kg) was extracted at room temperature with EtOH (95%, 6 5 L). The solvent was vacuum distilled. The condensed residue (218 g) was diluted with H2O (1:1) and worked up sequentially with petroleum ether (4 0.5 L), EtOAc (5 0.5 L), and n-BuOH (5 0.5 L). The solvents were distilled off to afford petroleumether (11.5 g), EtOAc (12 g), and BuOH (17.4 g) fractions. The EtOAc fraction was flash-chromatographed over a column of silica gel (100–200 mesh, 300 g) with elution by a gradient of petroleum ether–EtOAc (20:1 0:1) to afford 12 fractions. The first, fifth, and seventh fractions were chromatographed over a column of Sephadex LH-20 using CHCl3–CH3OH (1:1). The first fraction afforded 2 (58 mg) and 6 (8 mg); the fifth fraction, 1 (6 mg); the seventh fraction, 3 (26 mg), 4 (12 mg), and 5 (10 mg). The structures of 1–6 were elucidated using spectral data (1D and 2D NMR and ESI-MS) and a comparison with literature data [3–7].

Fatty acids in female’s gonads of the Red Sea fish Rhabdosargus sarba during the spawning season

Objective: To determine the fatty acids profiles in female fish, Rhabdosargus sarba (R. sarba) from the Red Sea during the spawning season. Methods: Monthly individual R. sarba were obtained from Bangalah market in Jeddah, Red Sea and transported to the laboratory in ice aquarium. The total length, standard length and weight were measured, fishes were dissected. Ovaries were removed, weighed and 10 mL of concentrated hydrochloric acid were added to 10 g of the ovary in a conical flask and immersed in boiling water until the sample was dissolved and the fat was seen to collect on the surface. The conical was cooled and the fat was extracted by shaking with 30 mL of diethyl ether. The extract was bowled after allowing the layers to separate into a weighed flask. The extraction was repeated three times more and distilled off the solvent then the fat dried at 100 °C, cooled and weighed. Then 50 mg of lipid was put in a tube, 5 mL of methanolic sulphuric acid was added and 2 mL of benzene, the tube well closed and placed in water bath at 90 °C for an hour and a half. After cooling, 8 mL water and 5 mL petroleum were added and shaked strongly and the ethereal layer was separated in a dry tube, evaporated to dryness. The fatty acid methyl esters were analyzed by using a Hewlett Packard (HP 6890) chromatography, a split/splitless injector and flame ionization detector. Results: In female R. sarba, a total of 29 fatty acids were detected in ovaries throughout the spawning season. The main fatty acid group in total lipid was saturated fatty acid (SFA, 28.9%), followed by 23.5% of polyunsaturated fatty acids (PUFA) and 12.9% of monounsaturated fatty acids (MUFA). The dominant SFA were palmitic and stearic, the major MUFA were palmitoleic and oleic, and the major PUFA were C18:2 and C22:2. During spawning stages, there were no significant differences in total SFA, MUFA and PUFA. The highest value of SFA was in late spawning (36.78%). However, the highest value of MUFA and PUFA was in spawning (16.70% and 24.96% respectively). During spawning season there were significant differences in total SFA between March (late spawning stage) and December (nearly ripe stage), P<0.05. Conclusions: From the present study it has been shown that 29 fatty acids were detected in ovaries of R. sarba throughout the spawning season. The main fatty acid group in total lipid was SFA followed by PUFA and MUFA. The dominant SFA were palmitic and stearic, the major MUFA were palmitoleic and oleic, and the major PUFA were C18:2 and C22:2. The highest value of SFA was in late spawning. However, the highest value of MUFA and PUFA was in spawning.

Preconcentration of radioiodine as AgI and purification from radiotellurium waste

A radiochemical method was investigated for separation and preconcentration of radioiodine from alkaline radiotellurium waste solution as Ag125I followed by recovery of 125I into aqueous NH3 solution and final purification by wet distillation. 125I–123mTe radiotracer solution (5 M NaOH) was equilibrated with prepared silver granules for different times and it was found that 125I was quantitatively removed from the aqueous phase after 7.0 h. The 125I-loaded silver was then equilibrated with ammonia solution in the presence of one of different reducing agents (namely, sodium borohydride, dextrose and zinc dust). Different concentrations of NH3 solution and reducing agents were studied. Quantitative recovery of 125I in the aqueous phase was achieved after 1.0 h of equilibration of 125I-loaded silver granules with 2.7M NH3 solution in the presence of Zn dust with a Zn:Ag molar ratio of 0.5. Purification of the recovered 125I was carried out by wet distillation from 20 % H2SO4 in the presence of H2O2. The distilled off 125I was received in a mixture solution of 0.1M NaOH and 0.01M Na2S2O3 with a radionuclidic purity of ≥99.99 %, radiochemical purity of ~98.8 % (as I− anions) and pH-value of ~13.

Preliminary Phytochemical Analysis of Pentapetes phoenicea L

The present study was undertaken to study the phytochemicals present in Pentapetes phoenicea from the family Sterculiaceae. In nature the plant grows in moist soil. It can also be grown under the shade of trees as well as in open sunny areas. For preliminary phytochemical analysis different solvents like petroleum ether, chloroform, acetone, methanol and distilled water were used. It revealed the presence of alkaloids, flavonoids, I. Introduction Phytoconstituents are the natural bioactive compounds found in plants. These phytoconstituents work with nutrients and fibres to form an integrated part of defence system against various diseases and stress conditions. Medicinal plants are of great importance to the health of individuals and communities. The medicinal value of these plants lies in some chemical substances that produce a definite physiological action on the human body. The most important of these bioactive constituents of plants are alkaloids, tannins, flavonoids and phenolic compounds (Hill, 1952). Pentapetes is native to a wide region of tropical South Asia from Shrilanka and India to northern Australia and the Philippines. It is naturalised and occurs almost throughout the drier parts of India, along roadsides, wastelands near habitaions, dumping grounds and swampy areas. The fruit of Pentapetes phoenicea causes constipation, heats the body, and is difficult to digest: removes 'kapha': cures fever, 'vata': and 'pitta' (Ayurveda). The root is employed as an emollient in Annam and in China. II. Material And Methods Plant material The whole plant of Pentapetes phoenicea was collected from the field. The different parts of the plant namely: leaves, stem and root were removed from the whole plant and air dried separately at room temperature. The dried parts were ground to powder and stored in polythene bags at room temperature. Chemical tests were carried out on different extracts to identify the constituents as described by Das and Bhattacharjee (1970), Gibbs (1974), Harborne (1984), Chhabra et al. (1984), Treases and Evans (1985), Daniel (1991), David (2000), Kokate et al. (2004). Preparation of extract: - For preliminary phytochemical analysis, 15 gm of the powdered plant material was taken in thimble of Whatman filter paper No. 1 and sohxelated with petroleum ether for about 12-16 hours. The petroleum ether extract (1a) was distilled off and the residue (1b) was dried overnight. The petroleum extract (1a) was tested for the presence of alkaloids, carotenoids, coumarins, flavonoids, steroids, phenolics and triterprnoids. The residue (1b) was Sohxelated with chloroform until complete decolourization takes place. The chloroform extract was collected and the residue (2b) was kept overnight for drying. This chloroform extract (2a) was tested for the presence of alkaloids, coumarins, flavonoids, steroids, phenolics and triterprnoids. The residue (2b) was Sohxelated with acetone for 4 - 5 hours and the acetone extract (3a) was collected. The residue (3b) was kept overnight. The acetone extract was tested for the presence of alkaloids, coumarins, flavonoids, steroids, phenolics and triterprnoids. The residue (3b) was Sohxelated with methanol for 10 - 12 hours. The methanol extract (4a) was collected and the residue (4b) was dried till next day. The methanol extract (4a) was tested for the presence of alkaloids, anthocyanins, anthocynidins, anthracene glycosides, cardiac glycosides, coumarins, flavonoids, steroids phenolics, tannins and triterpenoids. The residue (4b) was finally Sohxelated with distil water for about 10 - 12 hour. The water extract (5a) was tested for the presence of alkaloid, anthocyanins, anthocynidins, anthracene glycosides, carbohydrates, coumarines, flavonoids, steroids, phenolics, tannins, saponins, triterpenoids, gums and mucilage. The residue (5b) was discarded. Alkaloids: All 5 extracts (1a, 2a, 3a, 4a, and 5a) were tested for the presence of alkaloids with Mayer's, Dragendorff's and Wagner's reagent. 2ml of each extract was taken separately in 5ml of 1.5% v/v aqueous HCl and filtered. The resulting acidic solution was divided into 4 parts. Three parts were tested with Mayer's, Dragendorff's and Wagner's reagent and the fourth part served as blank. A faint turbidity, light opalescence or

Synthesis and characterization of new, liquid, branched poly(methylvinylborosiloxanes)

Abstract New liquid branched poly(methylvinylborosiloxanes) (br-PMVBS) of random structure were synthesized in three steps. By reacting boric acid with an excess of dimethyldichlorosilane (Me2SiCl2) in dry ether a “borosiloxane precursor”: tris(chlorodimethylsilyl) borate B(OSiMe2Cl)3 was prepared. In the second step of synthesis ether solution of B(OSiMe2Cl)3 was added to a mixture of appropriate organic chlorosilanes (Me2SiCl2, MeViSiCl2, MeSiCl3, and Me3SiCl) and all reagents were reacted with stoichiometric amounts of water, in the presence of pyridine (as an acceptor of HCl), in dry ether, at low temperature (usually at -10 to 0 C). In order to fully react (“to block”) trace silanol groups, reactions of intermediate PMVBS with additional batches of Me3SiCl were carried out in the third step, C5H5N·HCl was filtered off and washed with a dry ether. The solvent was distilled off from filtrates and low molecular weight siloxane oligomers were removed by a vacuum distillation at 130-150 C. Chemical structures of br-PMVBS were confirmed by elemental analysis and spectroscopic methods (FTIR, emission atomic spectroscopy ICP-AES, and NMR: 1H, 29Si and 11B). On the basis of analysis of their 29Si-NMR spectra the microstructure of polysiloxane chains was proposed. The prepared br-PMVBS had in their structures: triple branching borosiloxane units: BO1.5 and in some cases methylsiloxane moiety CH3SiO1.5 (T). They contained linkages: Si-O-Si, Si-O-B, vinyl(methyl)siloxane functional groups (CH2=CH)MeSiO (Dvi), dimethylsiloxane mers (CH3)2SiO (D), and non-reactive trimethylsiloxy terminal groups (CH3)3SiO0.5 (M), but they did not have: hydroxyl functional groups: Si-OH and B-OH, and sensitive to water B-O-B linkages. Molecular weights of br-PMVBS (Mn = 1500-3300 g/mol; Mw = 3800-7400 g/mol) and their polydispersity (Mw/Mn = 2.0-2.5) were determined by a size exclusion chromatography (SEC).

Effect of absorbed dose on the postradiation dry distillation of cellulose and lignin

The postradiation dry distillation of cellulose and lignin has been studied. During the course of irradiation to 3 MGy, the weights of samples remained almost unchanged. The overpoints of lignin and cellulose irradiated at 2.2 MGy decrease by ∼80° and ∼100°, respectively. A third of the condensate from cellulose and almost a half that from lignin were distilled off at lower temperatures. Thermally unstable compounds are formed in cellulose; these compounds are predominantly converted into furans upon subsequent heating. The distillation of irradiated lignin affords a smaller amount of tar, but it is richer in methoxyphenols. The aqueous organic fraction distilled off has a higher concentration of soluble organic compounds.

Electrochemical synthesis of biflavonoids

Biologically active biflavonoids have consistently attracted the attention of researchers [1]. However, only a few of these compounds have a broad spectrum of biological activity. This has prompted scientists to prepare their semi-synthetic and synthetic analogs [2]. Thus, several approaches including metal-catalyzed cross coupling, oxidative coupling, Ulmann condensation with nucleophiles, etc. have been used to synthesize biflavonoids [2]. We hypothesized that it would be possible to use an electrochemical method to prepare novel compounds based on flavonoids [3–5]. The flavonols isorhamnetin and kaempferide that were isolated earlier by us from Alhagi pseudalhagi (M. Bieb.) Fisch. were used for the synthesis. The flavonol (1 mmol) was dissolved in CH3CN (100 mL). The electrolysis was carried out in the presence of LiClO4 (0.1 M) in a cell with a diaphragm and a Pt anode of working surface 2 cm 2 and current density 5 mA/cm2 for 3 h. When the electrolysis was finished, about 90% of the solvent was distilled off. The remainder was used to separate the products by column chromatography over silica gel. In both instances, the principal products were recrystallized from acetone to afford light-brown powders in 0.22 ± 0.05 g yields. Their physicochemical and spectral characteristics were determined by known methods. Compound 1. C32H22O14, mp 285 ± 3°C, [ ]D 20 +39.7° (c 0.57, MeOH). UV spectrum (MeOH, max, nm): 251, 325, 356. IR spectrum (KBr, max, cm –1): 3430, 3370 (OH), 1681, 1600 (C=O), 1607, 1570 (aromatic C=C). Mass spectrum (EI, 70 eV), m/z (Irel, %): 630 (M +, 100), 615 (13), 315 (17). PMR spectrum (400 MHz, CDCl3, , ppm): 3.96 (6H, d, 3 , 3 -OCH3), 6.83 (2H, s, H-6, 6 ), 7.23 (2H, s, H-5 , 5 ), 7.52 (4H, s, H-2 , 6 , 2 , 6 ), 9.35 (2H, s, OH-4 , 4 ), 10.12 (2H, s, OH-7, 7 ), 10.82 (2H, s, OH-3, 3 ), 12.10 (2H, s, OH-5, 5 ). Compound 2. C32H20O12, mp 291 ± 3°C, [ ]D 20 +38.4° (c 0.52, MeOH). UV spectrum (MeOH, max, nm): 210, 271, 368. IR spectrum (KBr, max, cm –1): 3423 (OH), 1590 (C=O), 1520, 1460 (aromatic C=C). Mass spectrum (EI, 70 eV), m/z (Irel, %): 596 (M +, 100), 581 (12), 298 (22). PMR spectrum (400 MHz, CDCl3, , ppm): 3.83 (6H, d, OCH3-4 , 4 ), 6.83 (2H, s, H-6, 6 ), 7.36 (4H, s, H-3 , 3 , 5 , 5 ), 7.50 (4H, s, H-2 , 6 , 2 , 6 ), 10.16 (2H, s, OH-7, 7 ), 10.76 (2H, s, OH-3, 3 ), 12.17 (2H, s, OH-5, 5 ).

Radiation-thermal transformations and distillation of lipids and disperse systems on their basis

The radiation-thermal transformations of rape oil under conditions of postradiation distillation, radiation heating, and electron-beam distillation with auxiliary heating were studied. Diesel hydrocarbons were predominant in the condensate distilled off upon combined heating. The concentration of oxygen atoms decreased as a result of radiation-induced decarboxylation and dehydration processes. The irradiation of oil as a constituent of disperse systems facilitated purposeful deoxygenation, a decrease in the viscosity, and an increase in the yield of the gasoline fraction.

Total amino acid profiles of heat-processed fresh Elaeis guineensis and Raphia hookeri wines

Total amino acid (AA) profiles of heat-processed fresh Elaeis guineensis and Raphia hookeri wines were studied. Heating their fresh wines to 85°C, cooling and diluting to original volumes distilled off ethanol, but did not change their moisture and nitrogen contents. R. hookeri wine contained more (p<0.05) Phe, Val, Ala, Gly, Pro, Asp, Asn, His and Lys than E. guineensis wine which contained more (p<0.05) Met, Cys, Glu, Gln, Ser and Arg. Tyrosine, Leu, Ile and Thr contents did not vary (p>0.05). Glycine and Pro contents were low suggesting high globular protein concentrations. ∑basic AA/∑acidic AA ratios were >1 suggesting high basic protein contents. The E. guineensis and R. hookeri wines contained 58.25±0.56% and 56.79±0.4% essential AAs, respectively. Essential AA scores suggested Leu as their limiting AA. In conclusion, the wines can adequately meet daily nitrogen and essential AA needs when a 70kg adult drinks 1425.45ml.

Radiochemical precipitation studies for separation of iodine from tellurium and other trace impurities

Precipitation of radiotellurium, containing trace radioimpurities, has been carried out from sulfate media at different pH-values. The highest precipitation yield was achieved at the region of pH ~4–6. Quantitative uptake by the formed precipitate was noticed for (i) 54Mn, 110mAg and 125Sb over all the pH-range of study (pH 1.7–9.2), (ii) for 65Zn and 60Co in the regions of pH ~6–8 and pH 6–8.8, respectively, and (iii) for 134Cs in the region of pH 1.7–2.8, while its percent uptake fluctuated around 60.5 % in the region of pH 4.4–6.4. Further precipitation studies have been conducted for a mixture of 125I and radiotellurium from sulfate, nitrate and chloride media at pH-values of 6.0 and 7.5. The highest 125I recovery yield in the obtained supernatant was 95.0 ± 1.3 %, which was achieved with sulfate medium at pH 6.0 with percent uptake values of 5.0 ± 1.3, 98.9 ± 0.9 and 62.0 ± 4.6 % of 125I, 123mTe and 134Cs, respectively, and quantitative uptake of 54Mn, 110mAg, 125Sb, 60Co and 65Zn by the precipitated tellurium. Thereafter, the supernatant was further acidified with H2SO4 and boiled, after adding H2O2, for 3 h. >99 % of 125I was distilled off from the acidified supernatant. The distilled of 125I was received in 0.1 M NaOH + 1 % Na2S2O3 solution, with a radionuclidic purity of >99.99 %, radiochemical purity of >99.8 % as I− and pH ~13.