bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Synthesis, Characterization and Photophysical Properties of Some New Cyclotriphosphazene Derivatives Bearing Schiff Base
Authors: Aslan Fatih , Demirpence Zehra , Tatsiz Ramazan , Turkmen Hasan , Ozturk A. Ihsan , Arslan Mustafa 
Published: May 2008

AbstractHexa(2‐formylphenoxy)cyclotriphosphazene (o‐CHO‐C6H4O)6N3P3 (2) was obtained from the reaction of hexachlorocyclotriphosphazene (1) with salicylaldehyde in the presence of K2CO3 in THF solvent. A series of Schiff bases containing cyclotriphosphazenes such as [o‐(C6H5N=CH)C6H4O]6N3P3 (3), [o‐(1‐C10H7N=CH)C6H4O]6N3P3 (4), [o‐(p‐HOC6H4N=CH)C6H4O]6N3P3 (5), [o‐(2,3‐Cl2C6H3N=CH)C6H4O]6N3P3 (6), [o‐(3,4‐Cl2C6H3N=CH)C6H4O]6N3P3 (7), [o‐(3,5‐(CH3)2C6H3N=CH)C6H4O]6N3P3 (8), [o‐(C6H5CH2N=CH)C6H4O]6N3P3 (9), [o‐(p‐CH3OC6H4CH2N=CH)C6H4O]6N3P3 (10), [o‐(n‐CH3CH2CH2CH2N=CH)C6H4O]6N3P3 (11), [o‐(t‐(CH3)3CN=CH)C6H4O]6N3P3 (12), [o‐(n‐CH3[CH2]10CH2N=CH)C6H4O]6N3P3 (13) were synthesized from the reaction of hexa(2‐formylphenoxy)cyclotriphosphazene (2) with aniline, 1‐naphthylamine, 2‐aminophenol, 2,3‐dichloroaniline, 3,4‐dichloroaniline, 3,5‐di‐tert‐butylaniline, benzylamine, p‐methoxybenzylamine, n‐butylamine, tert‐butylamine and 1‐dodecylamine, respectively. The synthesized compounds were obtained in good yield and high purity. The structures of the compounds were confirmed by means of IR, NMR(1H, 13C, 31P) and elemental analysis. Photophysical properties of the cyclotriphosphazene derivates were investigated in dichloromethane solvent by UV‐Vis. spectrophotometry and spectrofluorometry (emission and excitation). Among the synthesized cyclotriphosphazene derivates, the compounds 2, 4, 5, 11 and 12 exhibit emission between 390 and 550 nm at room temperature.
Synthesis and Characterization of a New Framework Cobalt Phosphate with One‐dimensional Channel, Co3(H2O)4(PO4)2
Authors: Lin Yuan , Ning Guiling , Ye Junwei , Fan Yong , Wang Li 
Published: May 2008

AbstractA new cobalt phosphate, Co3(H2O)4(PO4)2 (1) has been synthesized under mild hydrothermal conditions and characterized by single crystal X‐ray diffraction. Crystal data for 1: orthorhombic system, Pnma, a = 10.582(2) Å, b = 18.289(4) Å, c = 5.0236(10) Å, V = 972.2(3) Å3, Z = 4. The compound displays complex three‐dimensional framework containing one‐dimensional 8‐membered ring channels. In this crystal structure, CoO4 and PO4 tetrahedra connect each other by sharing‐vertex to form the infinite two‐dimensional sheet which contains the edge‐sharing four ring chain and double zig‐zag chain, then these sheets are pillared by CoO2(H2O)4 octahedra.
Synthesis, Structure, and Luminescence Properties of Zinc(II) and Cadmium(II) Complexes containing the Flexible Ligand of 3,3′‐Thiodipropionic Acid
Authors: Yang Pei‐Pei , Li Bing , Wang Yu‐Hu , Gu Wen , Liu Xin 
Published: May 2008

AbstractTwo coordination polymers with mixed‐ligands, [ZnL(2,2′‐bipy)H2O]n (1) and [CdL(2,2′‐bipy)]n (2), (L=3,3′‐thiodipropionic acid; 2, 2′‐bipy=2, 2′‐bipyridine) have been synthesized and structurally characterized. Crystal structures reveal that the synthesized complexes consist of a one‐dimensional single‐chain and a one‐dimensional double‐chain, respectively. A prominent feature of complex 1 is the formation of a vagarious double‐chain by two neighboring single‐chains interleaving with each other. It is interesting for complex 2 to assemble the double chain into a 2D ordered supramolecular structure via π···π stacking interactions. Moreover, elemental analysis, IR, and luminescent spectra of complexes 1‐2 were also determined. At room temperature, complex 1 exhibits an intense emission at 360 nm upon 328 nm excitation, while complex 2 exhibits an intense emission at 472 nm upon 457 nm excitation, which can probably be assigned to the intraligand (π – π*) fluorescent emission.
5‐Azido‐1H‐tetrazole – Improved Synthesis, Crystal Structure and Sensitivity Data
Authors: Stierstorfer Jörg , Klapötke Thomas M. , Hammerl Anton , Chapman Robert D. 
Published: May 2008

AbstractDue to the highly explosive nature of 5‐azido‐1H‐tetrazole (1), its characterization has not been fully described in the literature yet. In addition, the previously published crystal structure was of low quality, and therefore the position of the hydrogen atom was not certain. In order to resolve these problems, 1 was prepared in an improved synthesis, and the results of the subsequent detailed reinvestigation and characterization are given. The reaction of cyanogen bromide with two equivalents of sodium azide at low temperatures yielded sodium 5‐azidotetrazolate, which was protonated using dilute hydrochloric acid. The product 1 was isolated and characterized using multinuclear (1H, 13C, 15N) NMR spectroscopy, vibrational (IR and Raman) spectroscopy and mass spectrometry. The structure of 1 in the crystalline state was determined using low‐temperature single‐crystal X‐ray diffraction. In addition, the optimized gas‐phase structures of the 5‐azido‐1H‐tetrazole and 5‐azido‐2H‐tetrazole isomers were calculated (MP2/aug‐cc‐pVDZ) and the electronic energies were compared. The heat of formation of 1 was calculated and several detonation parameters were estimated using the EXPLO5 software. The thermal behavior was investigated using DSC (differential scanning calorimetry) and the sensitivity of this highly energetic material was tested using the BAM drophammer, ESD and friction tester. X‐ray: 1: monoclinic, P21/c, a = 13.265(2) Å, b = 4.9693(6) Å, c =16.304(3) Å, β = 127.04(1)°, V = 857.9(3) Å3, Z = 8, ρ = 1.720 g cm−3.
Hydrothermal Synthesis and Structure of a New Three‐Dimensional Inorganic‐Organic Hybrid Polyoxomolybdate Based on Keggin Cluster Units
Authors: Chen Qi , Cai Chunxiu , Zhou Guangpeng , Xu Yan , Zhu Dunru , Zheng Xuefang 
Published: May 2008

AbstractA new 3‐D inorganic‐organic hybrid compound {[Cu(4,4′‐bipy)]3(4,4′‐bipy)}[PMo12O40]·2H2O (1) was hydrothermally synthesized and characterized by IR, TG and X‐ray diffraction analysis. Single crystal X‐ray diffraction confirms that this compound crystallizes in the triclinic crystal system, space group P‐1 with a = 10.9180(11), b = 12.3759(13), c = 13.0264(13) Å, α = 113.3560(10)°, β = 93.8730(10)°, γ = 99.0300(10)°. V = 1579.4(3) Å3, Z = 1. Structural analysis indicates that compound 1 exhibits a three‐dimensional structure, in which Keggin anions [PMo12O40]3− are linked by infinite [Cu(4,4′‐bipy)]+n chains through Cu‐O, and come into being a 3‐D inorganic‐organic hybrid open framework. The guest 4,4′‐bipy molecules and water molecules are filled in the channel formed by Keggin anions [PMo12O40]3− and [Cu(4,4′‐bipy)]+n chains.
Some Alkynyl‐Ruthenium Complexes Containing Di‐Imine and Tertiary Phosphine Ligands
Authors: Bruce Michael I. , Hall Benjamin C. , Skelton Brian W. , White Allan H. 
Published: May 2008

AbstractReactions between $\rm [RuCl_{2}(PPh_{3})_{2}(Bu^{t}_{2}bpy)]$, (1), and terminal alkynes in the presence of Tl[PF6], followed by chromatography on alumina, have given the mono‐alkynyl complexes $\rm [RuCl(C{\equiv}CR)(PPh_{3})_{2}(Bu^{t}_{2}bpy)]$ (R = Ph 2, C6H4NO2−4 3, CO2Me 4, Fc 5, CPh2(OH) 6), of which the single‐crystal XRD molecular structures of 3, 4 and 5 are reported.
Ag4I2SeO4 and Ag3ITeO4 – Two New Silver Solid Electrolytes
Authors: Pitzschke Dragan , Curda Jan , Cakmak Güliz , Jansen Martin 
Published: May 2008

AbstractTwo new silver solid electrolytes, Ag4I2SeO4 and Ag3ITeO4, have been synthesized by solid state reactions starting from stoichiometric mixtures of Ag2O and AgI with SeO2, or TeO2, respectively, at elevated oxygen pressures. The new materials have been characterized using powder X‐ray diffraction, differential scanning calorimetry, ionic conductivity measurements and single crystal structure determination. Both compounds, Ag4I2SeO4 and Ag3ITeO4, show an abrupt increase in the ionic conductivity in the temperature range of 50 to 70 °C and 90 to 130 °C, respectively. Ag4I2SeO4 has a silver ion conductivity of 1.6 × 10−3 at 30 °C with an activation energy of 0.22 eV, between 30 and 51 °C. It crystallizes as green crystals in Pna21 with a = 9.3514(1) Å, b = 13.1552(4) Å, c = 7.0886(4) Å, V = 871.80(6) Å3 and Z = 4. The crystal structure consists of isolated SeO4 tetrahedra separated by Ag+ and I− ions. Ag3ITeO4 crystallizes in P21/c with a = 19.6597(2) Å, b = 7.1240(4) Å, c = 13.3598(3) Å, β = 97.795(2)°, V = 1853.83(11) Å3 and Z = 12. The structure consists of $^{1}_{\infty}\rm [TeO_{4/2}O_{2/1}]^{2-}\}$ isopolyanions, extending along the b‐axis. The chains are separated by Ag+ and I− ions. Ag3ITeO4 has a silver ion conductivity of 7.4 × 10−5 Ω−1 cm−1 at 30 °C, with an activation energy of 0.27 eV between 25 and 100 °C.
Comparative Investigation of the Crystal Structure of LnCuSe2 Compounds (Ln = Tb, Dy, Ho, Er, Tm, Yb and Lu)
Authors: Daszkiewicz M. , Gulay L. D. , Shemet V. Ya. , Pietraszko A. 
Published: May 2008

AbstractLnCuSe2 compounds crystallize either in the monoclinic LaCuS2 (space group P21/c) or the trigonal CaLi2Si2 (space group $P{\bar 3}m{\rm 1}$) type of structure. The first group is formed by the light rare‐earth elements (Ln = La, Ce, Pr, Nd, Sm, Gd and Tb), the second by the heavier rare‐earth elements (Ln = Tb, Dy, Ho, Er, Tm, Yb, Lu). Accordingly, the formation of the structure type critically depends on the ionic radius of Ln. This dependence is clearly reflected by the spatial separation of the two structure types in a plot Vat(r) listing the average atomic volume versus the ionic radius of the rare earth element in its trivalent state. The crystal structures presented here exhibit trigonal symmetry. Seven crystal structures were determined by means of the single crystal X‐ray diffraction. The Se atoms form a hexagonal closest packing of spheres with AB stacking sequence of the atomic layers. The Ln atoms occupy 1/2 of the octahedral interstices. In each of the seven trigonal structures the Cu atoms are statistically distributed over 1/2 of the tetrahedral interstices with 50 % occupation probability.
The correlation of aflatoxin and norsolorinic acid production
Authors: Bennett Joan W. , Lee Louise S. , Vinnett Carolyn 
Published: May 2008

AbstractProduction of aflatoxins and norsolorinic acid by a mutant strain ofAspergillus parasiticus follows a similar course. Both substances are completely or partially inhibited when the mutant is grown in a chemically defined medium while illuminated continuously, at 37 C, in medium lacking zinc, and in the presence of para‐aminobenzoic acid. Higher yields of both compounds are obtained when the mold is grown in an enriched medium.
Low pressure hydrogenation of castor oil
Authors: Trivedi R. K. , Vasishtha A. K. 
Published: May 2008

AbstractCastor Oil was hydrogenated at low pressure (2.0–2.5 kg/cm2) and low temperature (125–135 C) using nickel catalyst to obtain a saturated waxy product rich in hydroxy stearic acid. High catalyst concentration was required to obtain good results. However, the catalyst could be recycled. The final product had iodine value below 3.0, hydroxyl value 155, and slip point of 84 C.
Subclassification of soybean Bowman‐Birk isoinhibitors
Authors: Tan‐Wilson Anna L. 
Published: May 2008

AbstractTrypsin inhibitors are proteins in the soybean which inhibit vertebrate pancreatic proteinases. Multiple forms of the two inhibitor classes, the Kunitz and the Bowman Birk inhibitors, are found in the soybean. The three Kunitz isoinhibitors are well characterized with regard to amino acid sequence, genetic inheritance and affinity for trypsin. Enough Bowman‐Birk trypsin inhibitors have been purified and characterized that identities can be established and inhibitors classified into subgroups. The first subgroup includes the classical doubleheaded inhibitor of bovine trypsin and chymotrypsin, BBSTI‐E; its proteolytic derivative, BBSTI‐D, and BBSTI‐E. Subgroup II has the double‐headed weak trypsin inhibitors, BBSTI‐C′, C and A″, related by proteolysis at the amino terminus. Subgroup III has the even weaker trypsin inhibitor BBSTI‐B′ and its apparent proteolytic derivative, BBSTI‐B. Subgroup I, II and III inhibitors have 70–80 residues with high half‐cystine and low glycine content. Subgroup IV consists of the strong trypsin inhibitor BBSTI‐A and its apparent proteolytic derivative BBSTI‐A′. These have about 200 residues, only two half‐cystine residues per molecule and 25 residue percent glycine. They crossreact better than do Subgroup III inhibitors with anti BBSTI‐E antibodies. While the cystine‐rich BBSTI‐E and BBSTI‐C are predominant in the cotyledon, the storage organ of the plant, the glycine‐rich trypsin inhibitors are predominant in the vegetative tissues of the seedling.
Antimicrobial properties of boric acid esters of alcohols
Authors: Watanabe S. , Fujita T. , Sakamoto M. 
Published: May 2008

AbstractA variety of boric acid esters of various alcohols were prepared and screened for antimicrobial activity in spent coolants of water‐based cutting fluids. Boric acid esters of triethylene glycol, dipropylene glycol, geranic acid monodiethylene glycol and some hydroxy amines, such as 5‐aminopentanol, showed good antimicrobial activity.
Computer modeling ofα‐ toβ′‐ form phase transitions using theoretical triglyceride structures
Authors: Hagemann James W. , Rothfus John A. 
Published: May 2008

AbstractIntermolecular energy calculations were performed on theoretical triarachidinα‐form structures as selected bond rotations converted them intoβ′‐forms with a chain‐tilt change in the glycerol region. Interactions across the methyl gaps amounted to only 2‐3% of the total energy in initialα‐ and finalβ′‐forms, but computer generated energy profiles duringα‐ toβ′‐phase transitions revealed highly repulsive regions due to the close approach of methyl groups. This methyl gap interaction, plus additional repulsive interactions in the lateral packing of molecules during rigid chain rotations, necessitated modification of certain chain movements during phase transition to reduce excessive repulsive energy. These results suggest that phase transitions proceed in a particular sequence of events that either distribute energy to promote further phase excitation or that lead to collapse into the stable polymorphic form. Phase transition energy curves also reveal that secondaryα‐ andβ′‐forms are possible and are dependent on the startingα‐forms, the direction of chain rotation and the subcell arrangement.
Sulphurization of jojoba oil for application as extreme pressure additive
Authors: Bhatia V. K. , Chaudhry A. , Masohan A. , Bisht R. P. S. , Sivasankaran G. A. 
Published: May 2008

AbstractIn order to develop jojoba oil‐based extreme pressure (E P) additives, a number of sulphurized jojoba oils have been prepared by varying the reaction conditions. The products differ in their amount of sulphur and in their structure. An attempt to predict their performance based on their structure reveals that it is not a simple addition of sulphur which is required; a certain level of cross linking and polymerization also are desirable to have a product which is effective as an E P additive.
Microbial transesterification of sugar‐corynomycolates
Authors: Göbbert Uwe , Schmeichel Armin , Lang Siegmund , Wagner Fritz 
Published: May 2008

AbstractGrowing cells ofArthrobacter sp. DSM 2567 and of the bacterium M9b were able to synthesize cell‐bound glycolipids. The carbon source determined the type of sugar moiety, whereas the α‐branched‐β‐hydroxy‐fatty acid remained constant. The incubation of resting cells of both bacteria in a simple buffer medium with various carbohydrates, including oligosaccharides and derivatives, led to the corresponding carbohydrate‐corynomycolates. Predominantly an enzymatic transesterification step seems to be responsible for the formation of new glycolipids; this was established by analytical data and 14C‐labeling studies. Concerning the substrate specifity, the transesterification reaction is characterized by a regioselective manner: (i) only the primary hydroxy‐groups at C‐6 (mono‐ and disaccharide) or C‐6′ (disaccharide) were acylated; (ii) 1‐β‐ or 4‐β‐substituents (including hydroxy groups) prevented the esterification; (iii) as for disaccharides with only one nonreducing moiety, the C‐6‐ and C‐6′‐positions were esterified one after another. In the presence of two nonreducing molecular ends with two possible C‐6‐esterification positions, both positions were substituted simultaneously.With regard to the studies on localization of the esterase after cell disruption, we found the enzymatic activity bound to the cell debris. In transesterification reactions comparable to resting whole cell experiments, the cell particles also were able to produce disaccharidecorynomycolates.
Determination of nitrogen content of fats and oils by the method of combustion/ion chromatography
Authors: Wijesundera R. C. , Ackman R. G. 
Published: May 2008

AbstractA method of combustion/ion chromatography (C/IC), initially developed for the determination of sulfur, has been extended to determination of total nitrogen in fats and oils. It is shown that nitrogen gas dissolved in the sample interferes with the determination, and that it is necessary to degas the sample before analysis. Moreover, there is a procedural blank for the nitrogen in the cylinder oxygen employed. Despite these drawbacks, the method has advantages over conventional methods, in that (i) measurements can be carried out with standard laboratory equipment, and (ii) nitrogen and sulfur, and possibly halogens and selenium, can be determined simultaneously.
Volatile components from trilinolenin heated in air1
Authors: Selke E. , Rohwedder W. K. 
Published: May 2008

AbstractHeadspace volatiles derived from trilinolenin heated to 192 C in air were collected, separated and identified using a microroom/GC‐MS/ computer system. Data from four analyses indicated more than 80 volatiles were present. Of these volatiles, 38 have been identified, and their combined GC peak areas represent 90% of the total integrated Chromatographic area. Dominant volatiles identified included: ethanal (2%), 2‐pentene (3%), ethanol (0.5%), 2‐propenal (20%), propanal (7%), ethyl furan (13%), 2‐butenal (4%), 2‐pentenal (4%), 2,4‐heptadienal (21%), 4,5‐epoxy‐2‐heptenal (3%) and 2,4,7‐decatrienal (2%). Most of the dominant and some of the minor volatiles are the predicted decomposition products of the four linolenin monohydroperoxides. However, the ratios of the predicted volatiles do not correspond to the monohydroperoxide ratios observed from autoxidized linolenate. Other primary and minor volatiles are present that are not predicted from the classical hydroperoxide decomposition hypothesis, which suggests that trilinolenin and some of the volatile compounds undergo further oxidation.
Factors affecting the desolventization of canola meal
Authors: Grant D. R. , Eager R. L. , Pepper J. M. , Mathews J. F. 
Published: May 2008

AbstractFactors affecting the level of residual solvent in hexane‐extracted canola meal included the moisture content of the crushed seed and the temperature of the hexane at the time of extraction, the duration of the extraction process and the severity of the cooking procedure prior to extraction. Low moisture, low temperature extraction, short exposure to excess hexane and mild cooking procedures all contribute to minimizing the levels of sorbed hexane after desolventization was complete. Dry heat could drive off only part of the residual hexane. Moist heat, as steam, was more effective.
The use of the polarograph to distinguish between the peroxide structures in oxidized fats
Authors: Lewis W. R. , Quackenbush F. W. 
Published: May 2008

AbstractA polarographic method for the determination of peroxides has been applied to fats and related esters. The data presented show that at least three different peroxide structures are present in early stages of oxidation and persist during extensive autoxidation. The peroxides of lard, methyl oleate, and methyl linoleate cannot be distinguished by the polarographic method used in this investigation. Autoxidation of lard at 100°C. is shown to give reduction curves which are much different from those obtained when lard is autoxidized at 45°C. Preliminary work has indicated that the chromatographic technique of Dugan et al. does not separate the peroxide structures which are determined polarographically.
International chemical union
Authors: Hoffpauir C. L. 
Published: May 2008

AbstractThis translation gives the minutes of the meeting in London during July 1947, incorporating the decisions made on the unified international methods and the plans for collaborative work to be done before the next meeting of the Commission. Methods under discussion included those for the sampling and analysis for moisture and oil specified for several oil‐bearing seeds. They also included those for alkalis and rosin in soaps and those for soluble and insoluble volatile acids and sterols in fats and oil, also for the determination of thiocyanogen and peroxide numbers in fats and oil. The organization of and the representation on the present International Commission on Fats and Oils are also given.
The application of the polybromide yield in the estimation of methyl arachidonate in methyl ester mixtures
Authors: White Mary F. , Orians Betty M. , Brown J. B. 
Published: May 2008

Summary

The preparation of and analytical data on three specimens of methyl arachidonate are described; these data include determinations of thiocyanogen number.

By a standard procedure polybromide yields are reported on five specimens of methyl arachidonate over a wide range of amounts of arachidonate brominated.

The empirical nature of the polybromide yield is demonstrated.

It is proposed to estimate methyl arachidonate in methyl ester mixtures by the interpolation from a standard curve which is drawn from bromide‐arachidonate data over a wide range of values.

The use of the proposed method along with the spectroscopic procedure is discussed.
Unusual Fatty Acid Isomers of Triacylglycerols and Polar Lipids in Female Limpet Gonads of Cellana grata
Authors: Kawashima Hideki , Ohnishi Masao , Ogawa Satoshi , Matsui Kenji 
Published: May 2008

AbstractTo investigate the occurrence of positional isomers of unsaturated fatty acids (FA) in triacylglycerols (TAG) and polar lipids (PL) in the female gonads of a dominant limpet, Cellana grata, fatty acid methyl esters (FAME) were fractionated according to the degree of their unsaturation by argentation thin‐layer chromatography. Their structures were elucidated by gas chromatography–mass spectrometry of a combination of their FAME and picolinyl esters. A total of 125 different FA ranging from 12 to 24 carbon atoms were identified, and 105 unsaturated FA, including 34 nonmethylene‐interrupted FA as minor components, were recognized. Although the major FA 16:0 and 18:1n‐7, which accounted for more than 20 and 10%, respectively, of total FA, were present in TAG and PL, higher amounts of 20:4n‐6 and 20:5n‐3 were present in PL. Unsaturated FA consisting of more than five different positional isomers were 17:1, 19:1, 18:2, 19:2, 20:2, 21:2, 22:2, 20:3, and 22:3, most of which were present in TAG. Furthermore, a larger variety of nonmethylene‐interrupted FA was found in TAG than in PL. This limpet gonad had a diverse assortment of unsaturated FA that comprised a wide range of unusual positional isomers with one to five double bonds.