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The addition to the methyl-substituted 4-t-butylcyclohexanone was studied, providing that the β-axial methyl and α-axial methyl groups hindered the axial and equatorial attacks respectively. The results obtained with fused-ring system ketones (four decalones) were explained by considering the similar stereochemical influence of 2-and 3-methylene substituents as corresponding methyl substituents. A rapid conformation equilibrium was also considered for cis-decalones. In addition, the axial attack, especially at a molar ratio of two or more, was found to be hindered by the α-equatorial methyl group. This hindrance was explained by assuming the half-chair form of the cyclohexanone ring in the transition state.

In neutral medium, picric acid (PA) reacts with chlorpromazine (CPM) hydrochloride with the formation of an orange compound, sparingly soluble in water, of molar ratio PA:CPM = 1:1. The compound is thermally stable up to a temperature of about 200 degrees C. The m.p. (178 degrees C) can be used for identification of picric acid as well as of chlorpromazine hydrochloride. Chlorpromazine picrate is extracted quantitatively with benzene, and the extract can be used for colorimetric determination of chlorpromazine hydrochloride. Beer's law is obeyed in the CPM concentration range 10-60 mug/ml.

Some 2-(trimethylsiloxy)-1,3,2-dioxaborolanes and borinanes have been synthesized by cleavage of corresponding trialkyltin or germanium derivatives with trimethylchlorosilane. Bis(4,4,6-trimethyl-1,3,2-dioxaborinane-2-oxy)-dimethylsiloxane was also synthesized by the reaction of triphenyltin derivative with dimethyldichlorosilane in (2:1) molar ratio. Some physical measurements, e.g., molecular weights, infra-red and p.m.r. spectra have been recorded.

The various microstructures obtained by the low temperature ( C 2 H 2 C 6 H 6 molar ratio. The densities and crystallographic parameters of the heat-treated composites are significantly affected by the type of microstructure. The rough laminar material has by far the most graphitic characteristics and is followed by the smooth laminar and isotropic materials, in that order.

Ruthenium(III) complexation with 2-amino-3-hydroxpyridine is studied spectrophotometrically. The violet-red complex (λmax 520 nm; ϵ 4460) contains metal and the ligand in 1 : 1 molar ratio, adheres to Beer's law from 0 to 16.5 µg/ml of ruthenium concentration and shows maximum and constancy in absorbance between pH 5.3 and 6.5. The complexation is used in the spectro-photometric determination of ruthenium in coexistence with several ions including some from platinum metals.

Mit Hilfe der Dunnschichtchromatographie wurde die Verteilung von Polymerhomolo-gen in Epoxidharzen mit mittleren Molgewichten bis hochstens 1500 bestimmt. Die mathematisch formulierte Voraussage der Verteilungsfunktion von Polymerhomologen stimmt mit den experimentellen Ergebnissen uberein, wobei die Dispersitatskonstante die charakteristische Grose darstellt und deren Abhangigkeit vom Molverhaltnis durch den Koeffizienten der Diversitat charakterisiert ist. Der Einflus des technologischen Herstellungsverfahrens von Epoxidharzen auf die Verteilung der Polymerhomologen ist bei niedrigmolekularen Harzen gering, bedeutungsvoll ist er jedoch bei Epoxidharzen vom minferen Molgewicht uber 600. The polymerhomologous distribution of epoxy resins having an average molecular weight below 1500 is determined by thin layer chromatography. The calculated prediction of the function of the polymerhomologous distribution is in agreement with the experimental results. The dispersity constant is the characteristic quantity and its dependence on molar ratio is given by diversity coefficient. The technology of the epoxy resin preparation on the polymer-homologous distribution is of low influence for low molecular resins but is essential for epoxy resins having average molecular weights above 600.

Aus (CH3)3PCH2 und (CH3)2GaCl, (CH3)2InCl sowie (CH3)2TlCl werden bei Ansatzen im Molverhaltnis 2:1 neue Dimethylmetall -dimethylphosphonium-bis(methylide) [(CH3)2MCH2P(CH3)2(CH2)]n (MGa, In, Tl) erhalten, von denen sich jeweils Dimere mit n = 2 isolieren lassen (1a–c). Diesen Ylid-Komplexen kommt nach den Molekulmasse-Bestimmungen und den Spektroskopischen Daten eine Achtringstruktur mit Alternierenden, durch CH2-Gruppen verbruckten Onium- und Metallat-Zentren zu. Auch die an sich unbestandige Tetraalkylthallat(III)-Einheit wird durch die Phosphoniumgruppierungen betrachtlich stabilisiert. Cyclic Ylid Complexes of Gallium, Indium, and Thallium The reactions of (CH3)3PCH2 with (CH3)2GaCl, (CH3)2InCl and (CH3)2TlCl in the molar ratio 2:1 yield new dimethylmetaldimethylphosphonium-bis(methylides) [(CH3)2MCH2P(CH3)2(CH2)]n (MGa, In, Tl). Of these the dimers with n = 2 can be isolated (1a–c) and are shown to consist of a novel eight-membered ring with alternating onium and metallate units bridged by CH2 groups, as inferred by molecular weight and spectroscopic data. Even the inherently labile tetraalkylthallate(III) group is thus stabilized by the neighbouring onium centers.

A glucomannan containing d -glucopyranosyl and d -mannopyranosyl residues in the molar ratio ca 1:3·3 has been extracted with water from the tubers of Orchis morio. The polysaccharide has a DP n of ca 665 and consists of a backbone of β(1 → 4)- linked glucosyl and mannosyl residues with ca. 7 branch points per molecule, probably at C3 positions of the hexose residues. The polysaccharide contains acetyl groups linked almost exclusively to the C2 or C3 positions of mannose residues. Structural studies showed that this water-extracted glucomannan is similar to the material of the mucilage globules which had been mechanically separated and isolated from the tissue of young tubers.

SummaryIn this study paired values of cellular sterol and phospholipid were determined after L cells were grown in medium known to induce changes in the level and kinds of cellular sterol. The sterol to phospholipid molar ratios computed from the paired values showed differences because, while the level of cellular sterol changed in response to exogenous sterol, no statistically significant differences in the levels of cellular phospholipid were apparent.When L cells were grown in the presence of concentrations of exogenous cholesterol ranging from 0 to 40 μug/ml, the sterol to phospholipid molar ratio ranged from 0.21 ± 0.01 to 0.33 ± 0.04, and, although the cellular sterol ranged from a low level almost exclusively of desmosterol (97%) to a 60% higher level almost exclusively of cholesterol (91%), no statistically significant differences were observed in the amount of cellular phospholipid. In another instance of growth in lipid-free medium a sterol to phospholipid molar ratio as low as 0.16 ± 0.03 was ...

The reaction of squaric acid, H2C4O4, with the trialkyl derivatives of aluminium, gallium and indium (R3M with R = CH3, C2H5) in a 12 molar ratio leads to bis(dialkylmetal) squarates. The Ga and In compounds dissociate in water forming R2M+ and C4O42− ions. From these solutions the squarates crystallize as mono- and dihydrates, respectively. The vibrational spectra (IR and Raman) are discussed.

Es wird uber Molverhaltnisse, Schmelzpunkte, uber Stabilisierungsmoglichkeiten eingeschlossener Gastkomponenten von Einschlusverbindungen des Perhydrotriphenylens, sowie uber die Moglichkeit der Stofftrennung uber derartige Addukte berichtet. Investigations on Perhydrotriphenylene Inclusion Compounds The molar ratio, melting points, and stabilization of guest components of perhydrotriphenylene inclusion compounds are reported. The possibility of separating compounds via the formation of such adducts is described.

Summary In the reactions of the binuclear complexes {fd} with bidentate N-ligands, the CO-bridges are broken with formation of mononuclear compounds: Mo(CO) 2 QL (molar ratio 1/2) [Q=Bipy, Phen; L= o-, m-, p -phenylenediamine], or binuclear complexes: [Mo(CO) 3 Q] 2 L (molar ratio 1/1) (Q=Bipy, Phen; L= p -phenylenediamine, aliphatic diamines). The structures of the new compounds are discussed on basis of their IR spectra.

Phenylbordichlorid reagiert je nach Molverhaltnis mit [(CH3)2SiNH]3 (5) zum Disilaborazin 8, Monosilaborazin 7und/oder B,B′, B″-Triphenylborazin (9). Bei der Umsetzung mit Octamethylcyclotetrasilazan, [(CH3)2SINH] 4 (12), im Molverhaltnis 1:1 entstehen NH4Cl, 8 und Polymere. Aus der Stoffbilanz folgt, das nur ein Teil von 8uber direkte Silazanspaltung entstehen Kann; der andere ist die Folge einer zu NH4Cl fuhrenden Substitutionsreaktion. Contributions to the Chemistry of Boron, LXVII. Silaborazines from Cyclosilazanes Phenyldichloroborane reacts with [(CH3)2SiNH]3 (5) to yield the disilaboranine 8, the monosilaborazine 7, and/or B,B′, B″-triphenylborazine (9), depending on the ratio of the reactants. Reaction with octamethylcyclotetrasilazane, [(CH3)2SiNH]4 (12), in a 1:1 molar ratio leads to NH4Cl, 8, and a polymer. Product analysis shows that only part of 8is formed by direct SiN-cleavage, the other part results from a substitution leading to NH4Cl.

The synthesis via interfacial and aqueous solution techniques of zirconium polyethers has been accomplished: Polymer yield seeks a maximum around a molar ratio of Cp2ZrCl2: Diol: Base of 1:1:2. Zirkoniumhaltige Polyather wurden auf folgendem Weg durch Grenzflachenpolykondensation und Losungspolykondensation hergestellt: Das Maximum der Ausbeute wird bei einem Molverhaltnis Cp2ZrCl2: Diol : Base von 1 : 1 : 2 beobachtet.

A detailed investigation of the reactions of the salt [Ph3(PhCH2)P][RuCl3(CO)(C7H8)](I; C7H8= bicyclo[2.2.1]-hepta-2,5-diene) with ligands (L) containing Group VB or VIB donor atoms is presented. Several different types of behaviour are found, depending on both the nature and amount of added L. For L = Me2S, Me2SO, and CH2CH–CN, the salts[Ph3(PhCH2)P][RuCl3(CO)L2], (II), have been isolated in high yield, whereas for L = AsPh3. SbPh3, and C5H5N, a mixture of (II) and [RuCl2(CO)L(C7H8)], (III), have been obtained [(I) : L = 1 :2 molar ratio]. Reaction of complex (I) with excess of SbPh3 gives (II), (III), and [RuCl2(CO)(SbPh3)3], (IV). In contrast, reaction of complex (I) with PPh3(1 :2 molar ratio) gives [{RuCl2(CO)(PPh3)2}2], (V), whereas with PMe2Ph, only [RuCl2(PMe2Ph)2(C7H8)], (VI), is isolated. A similar complex of type (VI) is formed with PMePh2, together with some [RuCl2(CO)(PMePh2]3(IV), whilst with 2,2′-bipyridyl or 1,10-phenanthroline (L′), the complexes [{RuCl2(CO)(L′)}n], (VII), and [Ph3(PhCH2)P][RuC3CO(L′)], (II), are obtained. Reaction mechanisms consistent with this observed variation in product composition are tentatively proposed.

Pastes of C3S (w/c ratio = 0.5) were steam cured at 25, 40, 60 and 90°C for 1 hour to 30 days. The results obtained have shown that, as the curing temperature rises, the induction period is shortened and the initial rate of hydration of C3S is increased; at longer curings, on the other hand, such hydration rate is considerably lowered. In order to explain the influence of temperature on the hydration reaction a new hypothesis has been proposed, which takes into account the C/S molar ratio as well as the surface properties of the hydrated silicate.

Vanadium(IV) forms a deep green complex with disodium maleonitrile dithiolate, in 0.05N sulphuric acid in 50 % acetonitrile solution, having maximum absorption at 580 nm. The colour system obeys Beer's law from 0.6 to 10 p. p. m. with optimum concentration range 2.5 to 10 p. p. m. of vanadium. The % relative error is 2.65. The determination of composition by continued variation and molar ratio methods suggests a metal to reagent ratio of 1∶4, the calculated dissociation constant being of the order of 10−18. The molar extinction coefficient is 4890 while the sensitivity is 0.01μg/cm2.

The reaction of [RhCl(CO) 2 ] 2 with tricyclohexylphosphine oxide (Cy 3 PO) (Rh/Cy 3 PO molar ratio 1) gives the dicarbonyl derivative, cis -[RhCl(CO) 2 (Cy 3 PO)], which is stable toward loss of carbon monoxide and subsequent dimerization. An X-ray structure determination shows that the rhodium is in a square-planar cis -dicarbonyl configuration.

(NSOF)2NPCl21 reagiert mit Ammoniak im Molverhaltnis 1:2 zu 1, mit Silylaminen (CH3)3SiNHR (RCH3, C2H5) im Molverhaltnis 1:1 zu 2 und 3, mit (CH3)3SiNR2 (RCH3, C2H5) zu 4 und 5. Schlieslich konnten aus (NSOF)2NPCl 2 und Disilylaminen [(CH3)3Si]2NR (RH, CH3, C2H5) die Verbindungen 6, 7 und 8 isoliert werden. Die IR-, Massen- und 1H-, 19F-und 31P-NMR-Spektren dieser Verbindungen werden mitgeteilt. Reactions of 3,3-Dichloro-1,5,2,4,6,3-dithiatriazaphosphor(V)in-S,S′-bis(oxide fluoride), of a Cyclic Phosphornitrilsulfanur Halogenide (NSOF)2NPCl2 reacts with ammonia in a molar ratio of 1:2 to give 1, with silylamines (CH3)3SiNHR (RCH3, C2H5) in a molar ratio 1:1 to yield 2 and 3, and with (CH3)3SiNR2 (RCH3, C2H5) to form 4 and 5. The reaction of (NSOF)2NPCl2 with disilylamines [(CH3)3Si]2NR (RH, CH3, C2H5) yields the compounds 6, 7, and 8. The i.r., mass, 1H, 19F, and 31P n.m.r. spectra of the above mentioned compounds are reported.

A laboratory study was conducted to determine the nature of the hydroxy-aluminum phosphate species present in wastewater treatment processes employing aluminum salts for the removal of phosphorus. At pH 5.0 the aluminum to phosphate molar ratio for optimum phosphorus removal was 1.44. Although several species may be formed, the chemical formula determined for the principal complex proposed by the authors is Al13 (OH)30 (H2PO4)9 · 18H2O. A postulated structure for this precipitate is presented.

The effects of NaF, KBF3OH and NaBF4 on the proton magnetic resonance spectra of La(III)-NTA chelate were investigated in 1:2 molar ratio of La to NTA in H2O solution at 35°C. The remarkable change of PMR spectra occurs in the presence of KBF3OH, which is not explained by simple effect of free F− formed by hydrolysis from BF4− and BF3OH−.

Chlor- und Fluorsulfonylisocyanat (1 a bzw. b) reagieren bei tiefer Temperatur mit Aldehyden im Molverhaltnis 1 :2 zu den Dioxazinonen 2, mit s-Trioxan und 1,3,5,7-Tetroxocan zum Tetraoxaazacyclodecanon 6. Die Reaktion mit Ketonen verlauft je nach deren Struktur verschiedenartig. In Sonderfallen entstehen Methylenaminosulfohalogenide wie 9. Meist bilden sich unter α-Substitution N-(Halogensulfonyl)-β-ketocarbonsaureamide wie 11. α,β-Ungesattigte Ketone liefern in einer (4 + 2)-Cycloaddition unter Einbeziehung der C C- Bindung Oxazinone 13. - β-Diketone addieren die Halogensulfonylisocyanate 1 a und b bei tiefer Temperatur am Sauerstoff'zu 17, bei Raumtemperatur werden sie am α-Kohlenstoff zu 18 substituiert. Analog erhalt man aus β-Ketocarbonsauren die Isobutantrione 28. Reactions of Aldehydes and Ketones with Chloro- and Fluorosulfonyl Isocyanate At low temperatures, chloro- and fluorosulfonyl isocyanate (la or b) react with aldehydes at a molar ratio of 1:2, to give derivatives of dioxazinone 2, and with s-trioxane and 1,3,5,7- tetroxocane, to give tetraoxaazacyclodecanones 6. With ketones the reaction course depends upon their structure; in special cases it results in the formation of methyleneaminosulfohalides 9. Usually N-sulfohalides of F-keto carboxamides such as 11 are formed by substitution in the a-position. a,P-Unsaturated ketones yield oxazinones 13 by a (4 + 2)-cycloaddition reaction including participation of the CC bond. - At low temperatures, the halosulfonyl isocyanates 1 a and b add to the oxygen of P-diketones forming 17, whereas at room tempera- ture they react at the z-carbon atom forming 18. In an analogous way, reaction with P-keto- carboxylic acid derivatives leads to formation of the isobutanetriones 28.

Conditions of formation for four types, A, B, C and D, of aluminum tetrametaphosphate, Al4(P4O12)3, were studied in the reaction of α -A12O3 or Al(OH)3 with NH4H2PO4.Type A is produced on heating α -A12O3 and NH4H2PO4 mixture above 750 C. Type B is easily obtained by heating α -A12O3 and NH4H2PO4 mixture at 500-550 C. Type C can be produced by heating α -A12O3 and NH4H2PO4 mixture at 600-700 C, but it is intermingled with type A or B. By heating 1-5% mixture of thus obtained type C in α -A12O3 and NH4H2PO4 at 525-575 C, pure type C is readily and reproducibly obtained. Type D is produced by heating a mixture of α -A12O3 and NH4H2PO4 in nitrogen stream or dry air at 500 C, while heating of this mixture in vacuum at 500-700 C gives type B as sole product. The type and yie1d of aluminum tetrametaphosphate formed greatly depend on the sort of aluminum compounds used as starting materials, molar ratio of the aluminum compounds and the phosphate, heating temperature and atmosphere.IR spectra and thermal transformation of aluminum tetrametaphosphate were also discussed.

Exopolysaccharides of a number of slime-producingAchromobacter strains, isolated from activated sludge, were prepared and analysed. They consist ofD-glucose,D-galactose, pyruvic acid and O-acetyl in the approximate molar ratio of 1:1:1:1/2. The polysaccharides were shown by methylation and partial hydrolysis to consist of unbranched chains of alternately arrangedD-glucose andD-galactose residues, exclusively linked by β-1,3-linkages, and with pyruvate substituents linked by acetal bonds at positions 0–4 and 0–6 of theD-galactose residues. The significance of the exopolysaccharides in relation to some relevant properties of activated sludge organisms is discussed.

Gas chromatographic study of the reaction between epichlorohydrin and methanol By means of the first three intermediate products the effect of the initial molar ratio of epichlorohydrin to methanol upon the distribution curve of the adducts has been followed. Besides the initial molar ratio, the ratio of rate of propagation to rate of initiation considerably affects the distribution. Quantitative results obtained by gas chromatography have been corrected for response at detection and compared with the results computed according to a mathematical model of the polyaddition of epichlorohydrin. It was found that the degree of occurrence of polyaddition is lower than was expected from the results of prior kinetic studies. By combining the results of gas chromatography and of the mathematical model, some kinetic problems of complex polyaddition reactions can be solved. A qualitative analysis of the results of gas chromatography confirmed for the initial addition steps a theoretical hypothesis of the formation of 2n isomers, where n is the number of moles added.

The tensammetric measurements indicated an appreciable interaction of o-cresol with piperidine as well as with triethanolamine in aqueous media. The sharp discontinuities in the mixtures of o-cresol + piperidine and o-cresol + triethanolamine at the mole ratio 3:1 for o-cresol to amine are observed by tensammetric, conductommetric and high frequency measurements. The shift of peak potential as well as increase in the magnitude of peak of the mixture have been utilized in determining the composition of the complexes by tensammetric measurements. The nature of formation of such complexes has been predicted. The nature of such interactions have been investigated by infra-red studies. The molar ratio of phenol to amine (piperidine and triethanolamine) are also estimated to be 3:1.

It was found that d-1-thioglucose was quantitatively converted to the corresponding disulfide with oxygen uptake by incubation with cell-free extract of Asp. niger. The molar ratio of the oxygen uptake to the d-1-thioglucose consumption was 0.22. The oxygen uptake was not affected by KCN, NH2OH and NaN3, but decreased by dialysis of the cell-free extract. The decrease of the oxygen uptake due to dialysis for 4 hr was recovered by the addition of FMN. From these results, a tentative mechanism of the oxidation of d-1-thioglucose was proposed.

A study was made of the copolymerization of 3-methylheptatriene-1,4,6 (MHPT) with methacrylic acid. It is shown that an increase in the MHPT concentration in the initial mixture exceeding a 1 : 2 molar ratio of MHPT to MAA does not lead to enrichment of the 3-methylheptatriene-1,4,6 copolymer; a copolymer of constant composition (MHPT : MAA= 1 : 2) is formed. A copolymerization mechanism is proposed.

The bilirubin (BR)-binding capacity of albumin in serum from cord blood, as estimated by Sephadex gel filtration, is less than that of adult serum. The binding site at which BR is tightly bound by albumin in pools of infant serum was saturated at an average BR/albumin molar ratio of 0.66, while in adult serum the ratio was 1.00. With further increase in BR concentration, albumin of infant serum bound BR less than that of adult serum. These findings appear to have clinical significance with respect to the danger of BR encephalopathy in icteric infants.

Summary. 1. The catechol amine containing granules of the cow adrenal medulla have been isolated as a fraction of high purity by density gradient centrifugation. They have a very high content of amines (34.3 μmoles/mg protein-N) and ATP (7.6 μmoles). Smaller amounts of ADP (0.89 μmoles), AMP (0.27 μmoles) and inorganic phosphate (1.45 μmoles) are also present. The adenosinephosphates represent at least 95 per cent of the acid soluble organic phosphates in the granules. 2. The molar ratio amines: ATP is 4.5: 1 or 3.9: 1, if the ADP and AMP in the granules are assumed to be split products from ATP. The sum of adenosinephosphates and inorganic phosphate represents an amount of acid equivalent to the catechol amines. This suggests that the amines are stored in intimate relation to the phosphates. 3. The osmotic properties of the granules and the amine content found in them make it necessary to assume that the amines are incorporated, together with the adenosinephosphates, in a complex molecular structure which prevents them from forming free ions or molecules in the intragranular water. The presence of large amounts of water soluble proteins (77—78 per cent of the total proteins) within the granules suggests that these proteins are a component in the postulated structure.

1. A method has been developed for obtaining plastic lubricants based on sodium terephthalamide. 2. The authors have studied terephthalamide lubricants made from MS-20s or DS-11 mineral oil, MAS-35 synthetic hydrocarbon oil, and FM-1322/300 polymethylphenylsiloxane. 3. The complex of terephthalamide and sodium benzoate has a higher thickening capacity and (in the case of a 1∶0.5 molar ratio) forms systems with higher colloidal stabilities than sodium terephthalamide of equal concentration. 4. It is shown that a γ -ray dose of 108 rad does not greatly change the main physical and chemical properties of terephthalamide lubricants.

A quantitative relationship can be obtained between the rotatory power and the molar ratio mannose/galactose for galactomannans having a structure consisting of a backbone of β-(1 → 4)-linked d -mannopyranose units with side chains of α-(1 → 6)-linked d -galactopyranose residues, by using an equation based on the principle of optical superposition and derived originally by Timell for native xylans. By adopting the usually accepted errors for the determination of optical rotations (±5° for polysaccharides) and the percentages of the sugar units (±5%), the natural, water-soluble galactomannans can be grouped into two classes, namely, those for which the differences between the experimental and calculated rotations lie in the range of the experimental error, and those for which the above differences are higher than the experimental error. For the last class, the existence of structural details not considered in the basic pattern used for the correlation is suggested.

The purpose of this investigation is to study the effects of various impurities which might be present in sea-water magnesia on the sintering and dead-burning properties.The influence of CaO, SiO2, Al2O3, Fe2O3 etc. additions on the sintering and dead-burning of magnesia has been investigated. The results obtained are shown as follows;(1) The sintering of dead-burned magnesia is influenced greatly by molar ratio of CaO/SiO2 and CaO/Fe2O3, (2) and the suggestion is made that the effect of additions in promoting the sintering of sea-water magnesia may be related to the chemical composition of the original sea-water magnesia.(3) The relation between the sintering characteristics of magnesia and molar ratio CaO/SiO2, CaO/Fe2O3, and CaO/Al2O3 was made clear.(4) There is no obvious relationship between the densification of dead-burned magnesia and the promoting growth of periclase crystals.(5) An optimum addition of additives beyond which sintering is inhibited was determined from the study of mineral composition of products.

An acidic polysaccharide has been isolated from the culture medium of T. mesenterica NRRL Y-6158. The heteropolymer contained D-xylose, D-mannose, D-glucuronic acid, and O-acetyl in the molar ratios of 7:5:1:0.7, respectively. Methylation analysis of the heteropolymer indicated that it was essentially a 1 → 3-α-linked mannopyranose backbone having approximately 80% of the backbone units substituted, thus forming a very highly branched structure. The substituents on the backbone were found to be D-glucopyranosyluronic acid end-group, β-linked to the O-2 positions of the mannopyranose units, and 2-O-β-D-linked xylopyranose side-chains, linked both to the O-2 and O-4 positions of the mannopyranose backbone. The methylation analysis suggests that these side-chains are probably two or three xylopyranose units long, although a limited variation in the length of the side-chains is a possibility.

ReCl5 was activated with Et3Al and oxygen to give a catalyst effective for the disproportionation of α-olefins as well as internal olefins. The catalyst species was deactivated by excess oxygen. The catalyst system consisting of either WCl6 or MoCl5 and Et3Al exhibited disproportionation activity in a short range of Al/M (M=W or Mo) molar ratio. The activity decreased with the increase in the Al/M ratio, but was restored by the introduction of oxygen.

A 23 Yates pattern experimental design was used to develop a mathematical model for the benzylation of p-chlorophenol with benzyl alcohol in the presence of perchloric acid as catalyst. A set of trials was planned with two replicates and the centre point trial with 4 replicates according to the design. The critical response was the yield of 2-benzyl-4-chlorophenol. Main effects as well as two- and three- factor interaction effects were statistically significant. The highest experimental yield was 91.6%. The experimental settings were 130°C, molar ratio of p-chlorophenol to benzyl alcohol 4:1, amount of 60% perchloric acid 5% by wt. of p-chlorophenol, addition time 2 h and stirring time 1 h. The difference between the experimental and predicted yields did not exceed 0.04%.Key words: p-Chlorophenol; Benzyl alcohol; Perchloric acid; 2-benzyl-4-chlorophenol; Experimental design DOI: 10.3329/bjsir.v45i2.5706Bangladesh J. Sci. Ind. Res. 45(2), 105-110, 2010

By the reaction of diamines with (CO)5CrC(OCH3)CH3 (molar ratio 12), the amino-bridged diaminodicarbene complexes are obtained in the case of saturated ω,ω′-diamines, whereas only mononuclear diaminomonocarbenes could be isolated from the reaction of the aromatic diamines benzidine and o-tolidine. This is attributed to reduction in basicity of the free amino group in the aromatic diaminomonocarbene complexes. This reduction is caused by the action of the strongly electron-withdrawing aminocarbene group on the free amino group through the aromatic system.

The sorption on silica of the complexes of Ag + , Zn 2+ , Cu 2+ , Co 2+ , and Co 3+ with ethylenediamine was studied. Using the static method the dependence of the capacity of the silica on the pH was evaluated and the molar ratio of released acid to the concentration of sorbed complexes was determined. It was found that over a wide pH range the amount of released acid is equal to the charge of the complex.

Kojic acid forms a stable chelate with Fe(III) ion at 1:1 molar ratio in weakly acidic media. In the absence of enough ligand, Fe(III)-kojate chelates tend to hydrolyse to an appreciable extent as a pH value of the solution goes up. At 1:1 molar ratio of ligand to metal ion four hydrolysed species; Fe(OH)A, Fe(OH) 2 A, {Fe(OH)A} 2 and {Fe(OH) 2 A} 2 ; are formed. In comparison with the 1:1 chelate, hydrolytic tendency of the 2:1 chelate decreases, and Fe(OH)A 2 and {Fe(OH)A 2 } 2 are the only hydrolysed products. Furthermore, in the case where more than three moles of ligand per mole of metal ion are present, such hydrolysis reactions do not proceed to a significant extent and stable chelate species formed are FeA 2 and FeA 3 . All the measurements were carried out at t = 25° and μ = 0·10 M, and the corresponding equilibrium and stability constants were estimated.

Synthetic tobermorite with a molar ratio CaO/SiO2 = 1.08 was studied as a model substance for the hydration products of Portland cement. By electrophoresis measurements it was found that at hydroxyl ion concentrations ranging from 10−3 to 2.10−2 M the sign of the surface charge is negative at low Ca concentrations and positive at high Ca concentrations. The zero point of charge is situated at 4 × 10−3 M Ca++, independent of the hydroxyl ion concentration. Under conditions prevailing in hardening normal cements, the resulting Ca hydrosilicate probably has a positive surface charge.

The long-term biological tolerance of hydrophilic gels containing ionogenic groups was investigated on animals (rats and pigs). The basic polymeric skeletons of poly(glyco1 monomethacrylate) and poly (N-ethyl methacrylamide) were modified by introducing acidic (carboxylic) and basic (tert-amino) groups, or both groups at a time. Introduction of both groups at a time in the molar ratio yielded an electroneutral polymer of ionogenic character. In all groups investigated here the implant was encapsulated by a fine capsule of collagen fibrous tissue; no signs of proliferation were observed. No calcification took place. The second part of the work consisted in an investigation of the tolerance of heterogeneous poly(glyco1 monomethacrylate) gels containing ionogenic groups,basic, acidic, and ampholytic, with continuously changing porosity. The microporous polymers (50–60% water in the starting mixture) were healed-in as compact gels by encapsulation with collagen fibrous tissue. The macroporous polymers (70% of water and more in the starting mixture) were encapsulated with a capsule of collagen fibrous tissue, from which newly formed capillaries,serous exudate and numerous cells penetrated into the implant. The more porous the material, the broader the zone of cellulization. In microporous polymers there was no calcification; in macroporous, calcification occurred in the margin of the implant or in its center. In contrast with other authors' findings,no effect of the chemical composition within the concentration range investigated upon the way of healing-in or calcification could be observed; only the effect of physical factors was evident.

The solubility of aluminium in NaF–AlF3 melts saturated with alumina has been investigated by analyzing quenched samples of the melts to determine the contents of metallic sodium and aluminium. The total solubility at 1 000 °C given as wt. % Al decreases with decreasing NaF/AlF3 molar ratio from 0.33 wt. % Al at NaF/AlF3 = 6.70 to 0.10 wt. % Al in cryolite (NaF/AlF3 = 3) and 0.075 wt. % Al at NaF/AlF3 = 1.70. The change in the solubility is primarily due to a change in the sodium content, while the aluminium content remains almost constant over the range investigated. The solubility in cryolite increases with increasing temperature from 0.10 wt. % Al at 1 000 °C to 0.14 wt. % Al at 1 060 °C. In cryolite at 1 000 °C the dissolved metal was found to consist of 0.065 wt. % Al and 0.090 wt. % Na. The fraction of the dissolved metal represented by sodium increases with increasing temperature.

A new procedure for preparing β-keto esters from methyl ketones, sodamide and diethyl carbonate using these reagents in the molar ratio of 1:3:3 is reported. The yields of β-keto esters approach to those of the preparation using sodium hydride as condensing agent. Furthermore, some cyclopentenolones were prepared from the β-keto esters synthesized by this-procedure.

Thermal decempesition of Na, Mg, K, Ca, Mn, Co, Ni, Cu, Zn, Sr, Cd, Ba and Pb formates were investigated by use of gas chromatography and thermogravimetry.(1) Upon the decompositions of Na, Mg, K, Ca, Mn, Zn, Sr, Cd and Ba fermates, H2, CO and CO2 were formed as the main gaseous products, together with small amounts of CH4, HCHO, HCOOCH3 and CH30H. These organic compounds were formed by secondary reactions from the othetgaseous products under the catalytic actions of the solid products (carbonates or oxides), (2) The deconipositions of Co, Ni, Cu and Pb formates proceeded through main proCess (a)and side process (b).The molar ratio of MO te M in the products was highest in the case of the decompqsition of Co formate and was about 50%. ln the case of Pb formatei, two kihds of weak catalytic action of solid products were observed, i. e. Pb metal produced autocatalyzed the decomPosition reacti n itself, but, PbO catalyzed the formation of organic compounds except for CH4. How- ever in the other cases, the autocatalysis of metal was pred minantly observed.

Reaction of ammeline and aromatic amine hydrochloride by fusion yielded 72% N, N'-diphenylammeline, mp 370-1°c (d) (molar ratio 1: 4, 250°c, 15 min); 32% N, N'-di-o-toluylammeline, mp 360-1°c (d) (molar ratio 1: 4, 240°c, 2 hr); 64% N, N'-di-m-toluylammeline, mp 342-3°c (d) (molar ratio 1: 5, 245°c, 15 min); 88% N, N'-di-p-toluylammeline, mp 364-5°c (d) (molar ratio 1: 4, 250°c, 20 mm). This reaction has not been known. Since N, N'-diarylureas are obtainable as by-products, these are assumed to be derived from decomposition by opening of s-triazine ring. The chemical structures of the product of this reaction were confirmed from determination of mixed mp. with N, N'-diarylammeline obtained by hydrolysis of 2, 4-bisarylamino-6-chloro-s-triazines and N, N'-diarylurea obtained by arylation of urea.

First the dielectric properties of rubidium-potassium nitrate mixed crystals were investigated. From the X -ray measurement, the D - E hysteresis loop observation, and the dielectric constant measurement, these Rb x K 1- x No 3 mixed crystals, of which there may exist a mixing limit at some molar ratio between 0.52 and 0.56, were found to be also ferroelectric in the phase III on cooling alone, as in pure KNO 3 , in contrast to the case of (NH 4 ) x K 1- x NO 3 . Next the results were discussed of the temperature dependence of lattice parameters measured by a high temperature X -ray powder diffractometer in relation with the phase transition behavior in KNO 3 , Rb 0.23 K 0.77 NO 3 , and (NH 4 ) 0.39 K 0.61 NO 3 . In every substance, a marked shrinkage of the unit cell was seen corresponding to the appearance of the ferroelectricity. From the obtained results, the discussion was made of the ferroelectric behaviors of the KNO 3 -series mixed crystals.

1. The previously unknownα-diethylthiophosphono-β, β-diphenylhydrazine,α-diphenylthiophosphono-β,β-diphenylhydrazine andα-diphenylthiophosphino-β, β-diphenylhydrazme were obtained. 2. In the synthesis ofα-diphenylthiophosphino-β, β-diphenylhydrazine, besides the desired products, the anhydride of diphenylthiophosphinic acid was obtained. 3. The formation of the anhydride of diphenylthiophosphinic acid was proved by counter synthesis, starting with diphenylthiochlorophosphine, diphenylthiophosphinic acid and 1,1-diphenylhydrazine, taken in a molar ratio of 1∶1∶1, in acetonitrile medium, at room temperature. 4. The structure of the synthesized diphenylthiophosphonohydrazines was confirmed by a study of the infrared spectra.

Potentiometric, conductometric and amperometric studies of the reactions of Cu(II) and Ni(II) with pyrid-2-yl carboxomide N-p-toluene sulphonyl and of Cu(II) and Pd(II) with benzofur-2-yl-carboxomide N-p-toluene sulphonyl indicate the formation of 1:2 (M:L) complexes at a pH 8–9. Fe(III) gives a 1:3 complex with benzofur-2-yl-carboxomide N-p-toluene sulphonyl. Cu(II) and Ni(II) give a 1:4 complex with phthalimide and succinimide. A 1:4 complex is also formed by the reaction of Cu(II) with glutarimide. A 1:2 complex is formed by the reaction of Co(II) with phthalimide and of Ni(II) with glutarimide. The stability constants of the complexes are determined by molar ratio and Bjerrum's method. The complexes could be isolated in the solid form, analysed chemically and their structures confirmed from i.r. and magnetic susceptibility measurements.

The interaction of bilirubin, linoleate and human plasma albumin was investigated in an isolated model system, designed to evaluate the competitive effect of free fatty acids (FFA) on the binding of unconjugated bilirubin by albumin. Increasing amounts of linoleate were added to bilirubin-albumin solutions at a constant molar ratio, and the mixtures passed through Sephadex G-25 columns to absorb the displaced bilirubin, which was then eluted and determined. In solutions with molar ratio bilirubin/albumin of 0.5 or 1.0 no displacement was evident when the molar ratio of linoleate relative to albumin was below 5. Above molar ratio of linoleate/albumin of 6, free bilirubin in the system rose sharply. In solutions with molar ratio bilirubin/albumin of 1.8, bilirubin dissociated from albumin markedly when the molar ratio of linoleate relative to albumin approached 4. Thus, the displacement of bilirubin starts only after most of the FFA binding sites on albumin with high association constants become saturated, and the competition involves mainly multiple binding sites with low association constants. In two groups of infants without or with hyperbilirubinemia requiring exchange transfusion, the molar ratio FFA/albumin in plasma ranged from 1.07 to 2.37. These values are much lower than those initiating the displacement of bilirubin in the in vitro system. The significance of FFA in causing shifts of bilirubin between intra- and extravascular pools is briefly discussed. It is suggested that FFA in neonates, although elevated, do not seem to reach concentrations, relative to albumin, which are effective in bilirubin dissociation.

Re-examination of our work on internal plasticization of polyvinyl chloride leads us to suggest a number of guidelines in the synthesis of internally plasticized PVC with optimum combination of strength and low temperature properties: (1) use of comonomers of solubility parameter around 8.5 or 10.5, (2) use of a high molecular weight (long chain) comonomers in a low molar ratio, and (3) their non-uniform incorporation in the PVC chain.