bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and optoelectronic properties of luminescent poly(p‐phenylenevinylene) derivatives containing electron‐transporting 1,3,4‐oxadiazole groups
Authors: Su Wen‐Fen , Yeh Kun‐Ming , Chen Yun 
Published: August 2007

AbstractThree random copolymers (P1–P3) comprising phenylenevinylene and electron‐transporting aromatic 1,3,4‐oxadiazole segments (11, 18, 28 mol %, respectively) were prepared by Gilch polymerization to investigate the influence of oxadiazole content on their photophysical, electrochemical, and electroluminescent properties. For comparative study, homopolymer poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐p‐phenylenevinylene] (P0) was also prepared by the same process. The polymers (P0–P3) are soluble in common organic solvents and thermally stable up to 410 °C under a nitrogen atmosphere. Their optical properties were investigated by absorption and photoluminescence spectroscopy. The optical results reveal that the aromatic 1,3,4‐oxadiazole chromophores in P1–P3 suppress the intermolecular interactions. The HOMO and LUMO levels of these polymers were estimated from their cyclic voltammograms. The HOMO levels of P0–P3 are very similar (−5.02 to −5.03 eV), whereas their LUMO levels decrease readily with increasing oxadiazole content (−2.7, −3.08, −3.11, and −3.19 eV, respectively). Therefore, the electron affinity of the poly(p‐phenylenevinylene) chain can be gradually enhanced by incorporating 1,3,4‐oxadiazole segments. Among the polymers, P1 (11 mol % 1,3,4‐oxadiazole) shows the best EL performance (maximal luminance: 3490 cd/m2, maximal current efficiency: 0.1 cd/A). Further increase in oxadiazole content results in micro‐phase separation that leads to performance deterioration. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4377–4388, 2007
Genetics and mechanism of resistance to deltamethrin in a field population of Spodoptera litura (Lepidoptera: Noctuidae)
Authors: Ahmad Munir , Sayyed Ali H , Crickmore Neil , Saleem Mushtaq A 
Published: August 2007

AbstractBACKGROUND: Spodoptera litura (F.) causes enormous losses in many economically important crops. The genetics of insecticide resistance has been extensively studied in several insect pests, but there is a lack of information on S. litura. Therefore, the genetics and mechanisms of the resistance of S. litura to deltamethrin were investigated.RESULTS: Bioassays at generation G1 gave resistance ratios of 9, 5, 41, 52 and 49 for deltamethrin, cypermethrin, profenofos, chlorpyrifos and triazofos respectively, when compared with the susceptible Lab‐PK strain. Bioassays at G4 with a deltamethrin‐selected population (Delta‐SEL) showed that selection gave resistance ratios of 63 and 7 for deltamethrin when compared with the Lab‐PK and UNSEL strains respectively. Cross‐resistance to other insecticides tested was observed in the selected population. A notable feature of the Delta‐SEL strain was that resistance to deltamethrin, cypermethrin, profenofos and chlorpyrifos did not decline over the course of five generations. Synergism tests with microsomal oxidase (MO) and esterase‐specific inhibitors indicated that the deltamethrin resistance was associated with MO and, possibly, esterase activity. Reciprocal crosses between the Delta‐SEL and Lab‐PK strains indicated that resistance was autosomal and incompletely dominant. A direct test of monogenic inheritance suggested that resistance to deltamethrin was controlled by more than one locus.CONCLUSION: Stability and dominance of resistance and cross‐resistance suggest that insecticides with different modes of action should be recommended to reduce pyrethroid selection pressure. Copyright © 2007 Society of Chemical Industry
Antitumor activity of chloroform fraction of Scutellaria barbata and its active constituents
Authors: Yu Jianqing , Liu Huibin , Lei Jiachuan , Tan Wenjie , Hu Xianming , Zou Guolin 
Published: August 2007

AbstractScutellaria barbata (SB) is widely used as an antitumor agent in China, but the antitumor components of SB are still unclear. The antitumor activity of various fractions of an ethanol extract of SB was studied in six human malignant cell lines. Bio‐based assays showed that non‐polar and low‐polar solvent fractions of SB had dose‐dependent cytotoxicities on six cancer cell lines. The IC50 values of these fractions on the cancer cell lines tested ranged from 16 to 70 µg/mL after 48 h of treatment. Among them, the chloroform fraction (CE‐SB) had the strongest cytotoxicity on cancer cell lines with a lower cytotoxic effect on a normal liver cell line. Bel‐7402 cell apoptosis induced by CE‐SB was examined using Hoechst 33258 staining, agarose gel electrophoresis and flow cytometry. CE‐SB dose‐dependently decreased the S phase content. Treatment with CE‐SB caused cytochrome c release and activation of caspase‐9. The antitumor activity of CE‐SB in vivo was also evaluated. At 60 mg/kg/day, CE‐SB significantly inhibited the solid tumor proliferation and increased the life span of ascites tumor bearing mice (p < 0.01). CE‐SB was subjected to bioassay‐guided isolation of the active compounds by chromatography on silica gel and Sephadex LH‐20. Phytol, wogonin, luteolin and hispidulin were obtained as cytotoxic constituents. Copyright © 2007 John Wiley & Sons, Ltd.
A multiple criteria decision‐making approach to estimate minimum environmental flows based on wetted perimeter
Authors: Shang Songhao 
Published: August 2007

AbstractMinimum environmental flows in rivers provide a certain level of protection for the aquatic environment. The relationship between wetted perimeter and discharge can be used to define the minimum environmental flows by the slope method (SM), or curvature method (CM), especially for cases with poor understanding of the aquatic ecosystem. SM and CM derived inconsistent values of minimum environmental flows. It was not clear which method better defined minimum environmental flow. Moreover, the computation and optimization procedures are both time consuming and error‐prone, especially for complicated wetted perimeter–discharge relationships. In this study, flow regulation for rivers was regarded as a multiple criteria decision‐making problem, with the objectives of minimum river discharge and maximum wetted perimeter. Ideal point methods (IPMs) with the scaling coefficient r = 1 (IPM1) and r = 2 (IPM2) were used to solve this model to determine optimal environmental flows. IPM was simple in computation, especially when the wetted perimeter–discharge relationship was given as scattered data pairs. Meanwhile, it was applicable to a wider range of wetted perimeter–discharge relationship than SM and CM. Environmental flows estimated by IMP1 are the same as that by SM. The analytical results for environmental flows using SM, CM, IPM1 and IPM2 were compared for wetted perimeter–discharge relationship expressed as power or logarithmic function. It showed that CM is not a good method to define environmental flows. SM with unity slope and IMP1 were recommended. CM, SM and IPM were examined for the determination of environmental flows in a river in North Xinjiang, China. Environmental flows for different transects of the studying river reach were estimated to be 21% of the mean annual flow by SM or IPM1, which provided the satisfactory wetted perimeter, water depth and average velocity for aquatic organisms. Copyright © 2007 John Wiley & Sons, Ltd.
Röntgendiagnostik plasma‐gestützt abgeschiedener dünner Schichten
Authors: Wulff Harm , Quaas Marion 
Published: August 2007

AbstractWir haben gezeigt, dass die Röntgen‐Diffraktometrie im streifenden Einfall und die Röntgen‐Reflektometrie einzeln und besonders in Kombination leistungsfähige Werkzeuge zur Charakterisierung plasma‐gestützt abgeschiedener Schichten sind. Beide Methoden arbeiten zerstörungsfrei. Die Schichten sind damit sowohl weiteren Diagnostikverfahren als auch der weiteren Nutzung zugänglich. Die Bestimmung chemischer, kristallographischer und physikalischer Eigenschaften führt zu einem tieferen Verständnis der Plasma‐Wand‐Wechselwirkung und ermöglicht eine gezielte Beeinflussung und Qualitätsverbesserung plasma‐gestützt abgeschiedener Schichten. An drei Beispielen haben wir den Einfluss der Plasmaparameter auf die Phasenbildung, die Defektstrukturentstehung und auf kinetische Prozesse vorgestellt.
Oberflächenwellen‐Strukturen in Cu‐Damaszentechnologie
Authors: Menzel Siegfried , Reitz Daniel , Schmidt Hagen , Albert Matthias 
Published: August 2007

AbstractEine neue Technologie zur Herstellung von Leistungs‐SAW‐Bauelementen mit vergrabenen Interdigitalwandlern aus einem Cu‐Dünnschichtsystem (Cu‐Damaszen‐Technik) wird beschrieben. Die so hergestellten Demonstratoren zeigen im Vergleich zu herkömmlichen Al‐Wandlern eine signifikant höhere Leistungsverträglichkeit und Lebensdauer. Die Eigenschaften der SAW‐Strukturen macht sie besonders attraktiv für neue Anwendungen, bei denen große SAW‐Amplituden und eine ebene Oberfläche der Struktur erforderlich sind.
Assessment of weld line performance of PP/Talc moldings produced in hot runner injection molds
Authors: Morelli Carolina L. , de Sousa José Alexandrino , Pouzada António S. 
Published: August 2007

AbstractWeld lines are weak regions in thermoplastic injection moldings caused by low molecular entanglement and unfavorable orientation. Their occurrence may lead to a significantly reduced mechanical performance of the products. Therefore, when weld lines are likely to occur in molded products, they must be taken into account during the mechanical and technological design processes. The weld lines become more critical when particulate fillers are compounded with the polymer. The performance of weld lines in talc‐filled polypropylene box moldings produced with a double‐gated hot runner mold is assessed in this work. The processing conditions were varied in order to cause morphology and tensile‐impact resistance changes. The weld performance at room temperature was assessed in terms of the energy absorbed in the impact tests. It was found that the performance depends on the injection temperature, the injection rate, and the orientation of the talc particles in the weld‐line plane. J. VINYL ADDIT. TECHNOL., 13:159–165, 2007. © 2007 Society of Plastics Engineers
Nuclear magnetic resonance for determining oil content of seeds
Authors: Conway T. F. , Earle F. R. 
Published: August 2007

AbstractTwelve seed oils containing a variety of functional groups were examined with a commercial broad‐band nuclear magnetic resonance (NMR) spectrometer. Instrument response (integrator readout) was directly related to hydrogen content of the oil (r=0.999), regardless of the structures present.NMR techniques were applied to the determination of oil in intact, partially dried seeds from 18 plant species containing 1.5舑53% oil having a variety of structures. The correlation between integrator readout (calculated to a uniform 25‐g sample weight) and oil content (determined by extraction with petroleum ether) is excellent (r=0.993). If the readout is further modified by a erratum for the variation in hydrogen content of the oils, the correlation becomes 0.996.
Hydrogen peroxide oxidation of tertiary amines
Authors: Hoh G. L. K. , Barlow D. O. , Chadwick A. F. , Lake D. B. , Sheeran S. R. 
Published: August 2007

AbstractOxides of tertiary amines, such as dimethyldodecylamine oxide, are known to be useful as detergents and foam stabilizers, and are now in commerical use. The results of an investigation leading to the selection of optimum conditions for producing these compounds are reported. A variety of hydrogen peroxide‐derived systems for amine oxidation were investigated. These included hydrogen peroxide in water and in nonaqueous solvents, and peroxy acids under various reaction conditions. Reductometric, acidimetric, and gas chromatographic procedures were used for analysis of reaction mixtures. The preferred reaction uses hydrogen peroxide as oxidant and water as the reaction medium. The product of this reaction is a 30舑40% solution of the amine oxide. Other factors affecting the rate and extent of conversion, such as amine purity, are discussed.
Determination of cyclic fatty acids by gas‐liquid chromatography
Authors: Black L. T. , Eisenhauer R. A. 
Published: August 2007

AbstractA method is described to determine cyclic fatty acids in cyclic monomers by gas‐liquid chromatography (GLC), which separates saturated straight‐chain esters from cyclic esters. The content of cyclic esters can be determined by integration of the area on the chromatograph under the cyclic peaks. GLC was applied to cyclic monomers made from linseed oil and from linolenic acid. Samples of both hydrogenated and nonhydrogenated cyclic monomers were analyzed; however, more reliable results were obtained on the hydrogenated samples. The results show a standard deviation of 0.25 for linseed oil and 0.36 for linolenic acid.Accuracy of the analysis was established by comparing data with that obtained by crystallization. The GLC method is approximately three times faster.
Gaseous ammonia as a refining agent for cottonseed oils
Authors: Zeitoun M. A. , Harris W. B. , Harris W. D. 
Published: August 2007

AbstractIn this investigation the application of gaseous ammonia to cottonseed oil refining was explored. The ammonia reacted quantitatively with the free fatty acids in the oil; its solubility in coftonseed oil was determined as a function of pressure. In 舠degumming舡 it was more efficient in removing phosphatides than other agents.A reduction in refining loss resulted for oils refined with gaseous ammonia as outlined and compared with the standard AOCS cup loss analysis. However, the oil colors were substantially higher even though the ammonia treated oils were re‐refined with caustic solution. Results using cottonseed oil‐hexane 舠miscellas舡 containing less than 70% oil showed low refining losses, but the colors were estremely high. Above 70% oil content the losses were higher, but the colors were lower. The colors never equalled 舠standard cup舡 results.
Iron sequestration by polyphosphates
Authors: Irani R. R. , Morgenthaler W. W. 
Published: August 2007

AbstractThe equilibrium sequestration of ferric and ferrous iron by polyphosphates has been measured at room temperature in the pH range of 4舑11. In general, sequestration decreases with increase in pH or increase in the chain length of the polyphosphate. The dissociation constants of ferric pyrophosphate and ferric tripolyphosphate have been estimated to be around 10蜢23. The polyphosphates form weaker ferrous complexes.
Composition of methyl esters from heat‐bodied linseed oils
Authors: Gast L. E. , Schneider Wilma J. , Forest C. A. , Cowan J. C. 
Published: August 2007

AbstractTwo heat‐bodied linseed oils, with Gardner viscosities of 37 and 55 min, were saponified, converted to their methyl esters, and separated into 2 fractions with urea and methanol. Gas‐liquid chromatography showed the adduct fraction, which comprised 38舑41% of the total methyl esters, to contain: palmitic, stearic, oleic, 舠linoleic,舡 and trace amounts of 舠linolenic舡 acid. The nonadducting fraction (59舑62%) of the total methyl esters was separated by molecular distillation at 140C/7 ॖ into a distillate and residue. The distillate amounted to 18舑25% of the total methyl esters and had an iodine value (I.V.) of 142舑145; its absorption at 232 mॖ indicates 2.5舑3.0% conjugated diene. Hydrogenation of this distillate gave a liquid product with an iodine number of 4 and a pour point of 蜢50C. Gas chromatograms of the distillate and its hydrogenated derivative indicated at least 5舑7 components. Comparison of these peaks with known fatty acid methyl esters indicates that the components of these fractions were either cyclic or branched esters. The nonadducting residue fraction was composed mainly of polymeric acids.
Removal of fatty soils from cotton in aqueous detergent systems
Authors: Powe W. C. 
Published: August 2007

AbstractA gravimetric method for studying the factors involved in removing fatty soils from cotton in aqueous detergent systems is described, and comparative data are given for removal of lanolin, lard, sebum, and hydrocarbon soils from cotton. Comparisons are made for a number of surfactants used in detergent formulations and effects of various builders are noted. Effects of some of the parameters of the wash bath such as detergent concentration, water temperature, and wash time are discussed. It is thereby demonstrated that:

Maximum fatty soil removal is attained from cotton in 5 min or less at 120F with 0.25% of a good detergent.
A group of six representative anionic and nonionic surfactants vary considerably in their ability to remove sebum from cotton.
In general, the relative ability of a detergent system to remove one fatty soil applies to other fatty soils also.
The most effective inorganic salts for removing sebum were sodium tripolyphosphate and tetrasodium pyrophosphate.
The most effective active‐builder combinations tested were built with sodium tripolyphosphate.
The improvement in fatty soil removal from cotton produced by building surfactants with inorganic salts was an additive or less than additive affect for the nonionics tested. With the anionies a few synergistic effects were noted. These effects were probably due to the inorganic salts lowering the CMC or increasing the size of the micelle.
Emulsification is probably an important mechanism in removing sebum from cotton.
Distribution of individual fatty acids in the crystallization fractions of lard
Authors: Arnold L. K. , Milloy A. D. 
Published: August 2007

AbstractDistribution of the individual fatty acids in the triglycerides of lard was determined by fractional crystallization, partial enzymatic hydrolysis with steapsin, and fatty acid analyses by GLC. It was found that none of the individual fatty acids corresponded to a random distribution in the crystallization fractions, but that the distribution of the total saturated and total unsaturated acids was very nearly random. The short chain fatty acids, C14 and C16, both saturated and unsaturated, were found to be more predominant in the 2‐position than in the 1‐ and 3‐positions of the lard triglycerides. All of the C18 fatty acids were found to be more predominant in the 1‐ and 3‐positions.
Assay of insecticides and herbicides in fats and oils
Authors: Cook J. W. 
Published: August 2007

AbstractTypes of residue and methods data required in the establishment of pesticide tolerances in food products is discussed. Emphasis will be on those products and methods involving fats and oils.A summary of some of the current research efforts in FDA in methodology for pesticidal residues in food products is given. These methods are in the nature of screening or sorting techniques which identify and determine a number of different chemicals in a single analysis. Adequate separation of these chemicals from the fats, oils, and waxes of food products is often the most difficult step in methods development.
Crossroads
Authors: McHale James , Lynch Merrill , Pierce  ,   Fenner & Smith Inc.
Published: August 2007

SummaryThe publicity on water contamination by detergent foams is awakening the public to the growing problems of air, water and soil pollution by all types of waste materials. While detergents account for only 5舑10% of total dissolved organic matter after conventional sewage treatment, their foaming tendency highlights their presence. Legislative action therefore seems inevitable.The branched‐chain alkylbenzene sulfonates and the branched‐chain alkylphenol polyglycol ethers are generally considered unsatisfactory from the standpoint of biodegradability. Straight‐chain alkylbenzene sulfonates are biodegradable, though tests to date indicate the rate of degradation is much slower than that of the fatty alcohol sulfates. In general, the lower molecular weight species of each detergent type produces more foam on agitation, but degrades more rapidly than the higher molecular weight species.The extensive research work on biodegradables may open new usage potentials for both animal fat and vegetable oil derivatives. It has already led to development of alpha olefins derived from petroleum sources, and unless producers and processors of agricultural fats and oils work equally hard on developing their own derivatives, the petroleum‐based raw materials will take over even more than soap舗s former detergent market. Right now, the natural fats and oils seem to have a built‐in advantage of biodegradability to answer the basic problems of detergent suds and stream pollution
Developments in appliances which might influence the detergent and textile industries
Authors: Davis Richard C. 
Published: August 2007

AbstractThe interrelation of researches in detergents, appliances, and textiles is discussed, showing how a major development in one industry can force reactions by the other industries. Several new appliance developments, which might affect detergents, include a water softener built onto a washer and two novel washing systems. The possibilities of a home dry‐cleaner are reviewed, as are appliance industry reactions to the development of permanent‐press fabrics by the textile industry. Some predictions about the washing machine of the future are presented.
Composition and stability of pecan oils
Authors: Pyriadi Thanun M. , Mason Michael E. 
Published: August 2007

AbstractAnalyses of pecan oils by GLC and mass spectrometry showed the presence of palmitic, stearic, oleic, linoleic, and linolenic acids. The TLC of the nonsaponifiable materials of pecan oil, followed by identification of individual zones, revealed the presence of carotenoids, α‐tocopherol, other tocopherols, and an Emmerie‐Engel positive compound which was unknown. A quantitative estimation of tocopherols was achieved in pecan oils from eight varieties. Total tocopherol content was correlated with oil stability; however a better correlation with stability was observed when both tocopherols and the degree of unsaturation of the oils were taken into account.
Nonvolatilealpha‐branched chain fatty esters. II
Authors: Bilyk A. , Eisner A. , Ault W. C. 
Published: August 2007

AbstractA group of nonvolatilealpha‐branched esters was prepared by the di‐tertiary butyl peroxide‐promoted addition of normal esters to terminal olefins containing methyl branches or aryl groups. Methyl stearate was added to 3,7‐dimethyl‐1‐octene, 3,5,5‐trimethyl‐1‐hexene, and 4‐phenyl‐1‐butene. The reaction with 2,4,4‐trimethyl‐1‐pentene, a terminal alkene with a methyl branch at the internal ethylenic carbon, was not successful. Benzyl 2‐(4‐phenylbutyl) octadecanoate was prepared by transesterification of the corresponding methyl ester. Benzyl 2,2‐dimethylpropanoate, which has no α‐hydrogen in the acyl portion of the molecule, was added to 1‐hexadecene to form α‐hexadecylbenzyl 2,2‐dimethylpropanoate. Lubricant evaluation data were obtained on the above compounds.
Interesterification. I. Change of glyceride composition during the course of interesterification
Authors: Freeman I. P. 
Published: August 2007

AbstractChanges in composition produced in monounsaturated triglycerides during the course of interesterification, before full randomization is achieved, have been followed by using thin‐layer chromatography. Results indicate that intraesterification, in which interchanges take place between positions on the same molecule, occurs at a faster rate than, the general randomization which results from interesterification.The reaction is found to proceed according to the expression log a α t, where ‘a’ is the proportion of fatty acid components not changed in position by the reaction. This expression is of general application to triglyceride interesterifications and provides a basic equation in terms of which the effects of temperature, catalysts, and other experimental conditions can be studied.