bluuebunny/crossref_metadata_2025_split huggingface dataset:
Total Synthesis of (+)‐3‐Oxacarbacyclin 2. Stereoselective Deprotonation and Completion of the Synthesis
Authors: Ossenkamp K. L. , Gais Hans‐Joachim 
Published: July 2007

AbstractThe asymmetric synthesis of (+)‐3‐oxacarbacyclin (1) from cis‐bicyclo[3.3.0]octane‐2,5‐dione has been achieved. A notable feature in this synthesis is an asymmetric Horner‐Wadsworth‐Emmons (HWE) reaction. A further key step is the stereoselective deprotonation of a chiral bicyclic ketone, having a high local symmetry about the carbonyl group, with lithium (R,R)‐bis(phenylethyl)amide in the presence of lithium chloride. The route described also allows the synthesis of the anti‐thrombotic and anti‐metastatic prostacyclin analogs cicaprost and eptaloprost. The flexibility of this route should also provide access to further side‐chain modified analogs of 1.
Molecular Meccano, 27. A Template‐directed Synthesis of a Molecular Trefoil Knot
Authors: Ashton Peter R. , Matthews Owen A. , Menzer Stephan , Raymo Françisco M. , Spencer Neil , Stoddart J. Fraser , Williams David J. 
Published: July 2007

AbstractA design logic for the self‐assembly of a molecular trefoil knot and of its isomeric trivial knot is described. The approach relies on the formation of a double‐stranded supramolecular complex between an acyclic π‐electron rich 1,5‐di‐oxynaphthalene‐based polyether and an acyclic π‐electron deficient bipyridinium‐based tetracation. The reversible complexation of the two acyclic complementary components in solution is followed by the irreversible formation of covalent bonds connecting the termini of these two precursors within the supramolecular complex, affording both a trefoil knot and a trivial knot, though only in extremely low yields. The isomers were separated by preparative high‐performance liquid chromatography and characterized by liquid secondary ion mass spectrometry which revealed the binding of up to two ammonium ions in the case of only one of the two isomers – namely, the trivial knot. In addition, we have performed binding studies between some model acyclic and macrocyclic 1,5‐dioxynaphthalene‐based polyethers and the bipyridinium based precursor of the knots. One of the complexes was also characterized in the solid state by X‐ray crystallography which revealed the formation of a [2]pseudorotaxane in the solid state.
Regioselective Cyclizations of Delocalized 1,3‐Amide Dianions with Oxalic Acid Dielectrophiles
Authors: Langer Peter , Döring Manfred , Görls Helmar , Beckert Rainer 
Published: July 2007

AbstractA novel strategy for the synthesis of nitrogen‐rich heterocycles by regioselective C,N‐cyclization of ambident dianions with oxalimidoyl dichlorides is reported. One‐pot reactions provide γ‐iminotetramic acid amides 1, radialenes 2 and tetraimino‐diazaspiro[4.4]nonenones 3. Chemical properties and structural features of the new heterocyclic systems, including the tautomerism of 2, were investigated.
The Nazarov Reaction of 1‐Acryloyl‐1,3,5‐cycloheptatriene; a Novel Synthetic Pathway from 1,3,5‐Cycloheptatriene to Dihydro‐1(2H)‐azulenone
Authors: Oda Mitsunori , Yamazaki Takafumi , Kajioka Takanori , Miyatake Ryuta , Kuroda Shigeyasu 
Published: July 2007

AbstractThe title compound, 1‐acryloyl‐1,3,5‐cycloheptatriene (3), was prepared from 1,3,5‐cycloheptatriene in four steps, and subsequently its Nazarov cyclization of 3 was studied in order to develop a novel synthetic pathway to dihydro‐1(2H)‐azulenone. While the reaction of 3 in sulfuric acid afforded 1‐tetralone (5) in a low yield, the reaction in a mixture of phosphoric acid and formic acid at room temp. produced 3,8‐dihydro‐1(2H)‐azulenone (6) and 3,3a‐dihydro‐1(2H)‐azulenone (7) in yields of 46 and 13% respectively. Using stannic chloride as the acid in the reaction gave 6 and 7 in a slightly better combined yield.
Mechanical properties of metastable glacial till before and after water‐induced compaction
Authors: Stock Oliver , Lesturgez Gregory , Bens Oliver , Hüttl Reinhard F. 
Published: July 2007

AbstractThe mechanical properties of metastable soils have been approached from different backgrounds by civil engineers and soil scientists, with the main focus being on water‐induced self‐compaction rates. This study was conducted to determine the rebound‐recompression properties of metastable soil before and after wetting and to study the effect of water‐induced compaction on the mechanical stability depending on the overburden pressure. Rebound and recompression properties were measured with oedometer tests using sieved sandy loam, taken from a nonweathered Saalian glacial till layer, as the metastable test soil. The mechanical stability (preconsolidation load) of the dry and wetted soil was derived mathematically from recompression data after the test soil was unloaded. Void‐ratio changes during unloading and reloading were on a low level (Δe = 0.03). Rebound and recompression rates of the dry samples increased with load, whereas the void‐ratio change was twofold higher during recompression. Rebound rates of the wetted samples tended to decrease with load, while the recompression rates remained constant. Preconsolidation load calculated for the dry samples overestimated the simulated overburden pressure, whereas the wetted samples showed a high congruence. In both cases, the point of greatest curvature estimated in the earlier step of deviation gave values that were more realistic to the loads from which the unloading started. Our results indicate that both dry compaction and water‐induced compaction induce primarily plastic deformation. Furthermore, we found that in both the dry and wetted state the mechanical stability of the soil reflecting the overburden pressure remained constant.
Amphiphilic Multicore‐Shell Particles Based on Polyphenylene Dendrimers
Authors: Yin Meizhen , Bauer Roland , Klapper Markus , Müllen Klaus 
Published: July 2007

AbstractSix‐arm and twelve‐arm star polymers have been synthesized by ATRP on the template of first‐ and second‐generation polyphenylene dendrimers. Star polymers with amphiphilic double‐shell of hydrophilic HEMA and styrene were also synthesized and their behavior toward different solvents was studied. The results show that the size, conformation, and surface polarity of the amphiphilic double‐shell species can be adjusted by using solvents with varying polarity. In polar media, the hydrophilic blocks turn outwards, whereas in non‐polar media, the hydrophobic segments move to the molecules' surface; the macromolecule can rearrange its structure depending on the polarity of the surrounding media.magnified image
Improved k‐space trajectory measurement with signal shifting
Authors: Beaumont Marine , Lamalle Laurent , Segebarth Christoph , Barbier Emmanuel L. 
Published: July 2007

AbstractVarious techniques for k‐space trajectory measurement have been described in the literature. Self‐encoding gradient techniques are time‐consuming due to the high number of phase‐encoding steps needed. The approach with localized slices is faster, but its use apparently has not been reported in the context of high spatial resolution experiments. Signals associated with high k‐space frequencies may then reach low or even zero values, and this may result in errors in the estimate of the trajectories at the k‐space periphery. To overcome this problem without increasing the measurement duration of the localized slice method too much, a new approach is proposed in which an addition dephasing gradient applied prior to the gradient to be measured shifts the signal maximum. Magn Reson Med 58:200–205, 2007. © 2007 Wiley‐Liss, Inc.
ZnO: From basics towards applications
Authors: Klingshirn C. 
Published: July 2007

AbstractSeveral hundred thousands of tons of ZnO are used by per year, e.g. as an additive to concrete or to rubber. In the field of optoelectronics, ZnO holds promises as a material for a blue/UV optoelectronics, alternatively to GaN, as a cheap, transparent, conducting oxide, as a material for electronic circuits, which are transparent in the visible or for semiconductor spintronics. The main problem is presently, however, a high, reproducible and stable p‐doping. We review in this contribution partly critically the material growth, fundamental properties of ZnO and of ZnO‐based nanostructures, doping as well as present and future applications, with emphasis on the electronic and optical properties including stimulated emission. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Expression of murine DNA methyltransferases Dnmt1 and Dnmt3a in the yeast Saccharomyces cerevisiae
Authors: Bulkowska Urszula , Ishikawa Takao , Kurlandzka Anna , Trzcińska‐Danielewicz Joanna , Derlacz Rafał , Fronk Jan 
Published: July 2007

AbstractMurine DNA methyltransferases Dnmt1 and Dnmt3a were expressed in the yeast Saccharomyces cerevisiae. Adjustment to yeast preferences of the nucleotide sequences upstream and downstream of the translation initiation sites of both cDNAs was needed to obtain significant levels of the methyltransferases. Both proteins were correctly localized to the nucleus and their presence had no measurable influence on the functioning of yeast cells. Both Dnmt1 and Dnmt3a expressed in yeast cells were enzymatically active in vitro, and in vivo in the genomic DNA of the transgenic S. cerevisiae ca. 0.06% and 0.4%, respectively, of cytosines became methylated. This level of DNA methylation is about 100‐ to 10‐fold less than that observed in mammalian cells. The constructed system may be used to investigate the in vivo specificity of individual mammalian DNA methyltransferases and to search for additional factors needed to allow more efficient in vivo methylation of chromatin‐contained DNA and to study their mechanism of action. Copyright © 2007 John Wiley & Sons, Ltd.
Experimental evaluation of environmental enrichment of sea turtles
Authors: Therrien Corie L. , Gaster Lauren , Cunningham‐Smith Petra , Manire Charles A. 
Published: July 2007

AbstractAlthough behavioral studies have been conducted at zoos and aquaria for years, documentation concerning the effectiveness of environmental enrichment has dealt primarily with terrestrial animals and marine mammals. Few enrichment studies have been conducted on reptiles. For this study, behavioral observations were made on four captive sea turtles (three loggerhead, Caretta caretta, and one blind green, Chelonia mydas) with enrichment present and absent. Enrichment devices were modified for the special needs of the blind turtle. Behaviors were classified as Resting, Pattern Swimming, Random Swimming, Focused Behavior, Aggression, Hiding, Orientation, and Noncategorized Behavior. It was hypothesized that, when enrichment was present, a decrease in Resting and stereotypic Pattern Swimming would be seen along with an increase in Random Swimming and Focused Behavior. It was found that, when no enrichment devices were present, 77% of the turtles' time was spent in Resting and Pattern Swimming. When enrichment devices were provided, 88% of their time was spent in Random Swimming and Focused Behavior with only 8% spent in Pattern Swimming and Resting. Statistically, there were significant increases in Random Swimming (three of the four turtles) and Focused Behavior (4/4) and significant decreases in Resting (3/4) and Pattern Swimming (3/4) when enrichment devices were present. These results suggest that environmental enrichment is as effective with marine reptiles as has been found with other animals and should be encouraged for all captive sea turtles. Zoo Biol 26:407–416, 2007. © 2007 Wiley‐Liss, Inc.
Glycerolysis of peanut and mustard oils
Authors: Mehta T. N. , Rao C. V. N. , Laxmikanthan V. , Shah S. N. 
Published: July 2007

SummaryThe glycerolysis of peanut and mustard oils has been carried out in the presence of catalysts such as lime and litharge. The effect of time and temperature on the rate of glycerolysis has been studied. The monoglyceride contents and hydroxyl values of the washed samples have been determined. The diglyceride and triglyceride contents of the products have been computed from the monoglyceride percentage and the hydroxyl values.
Determination of hexachlorophene content of soaps using ferric chloride reagent
Authors: Larson Harry L. 
Published: July 2007

SummaryHexachlorophene is determined in soap by measuring the color produced by reaction with ferric chloride in alcohol solution with controlled conditions of time and temperature. The precision is within ±5% of the hexachlorophene content at the 1/2% level or above. As a criterion, any soap that will give a finely dispersed barium soap and that does not form a precipitate with ferric chloride under the conditions of the method give good results. This includes all milled bar soaps. The effect of phenolic perfume ingredients on the result is negligible. Five per cent abietic acid in the fatty acid composition has no effect on the result. The method is slightly modified for use with liquid potassium soaps.
Detergency properties of sodium carboxymethyl cellulose‐soap‐builder systems
Authors: Vaughn T. H. , Kramer M. G. 
Published: July 2007

SummaryData have been presented which illustrate the detergency properties of soap‐sodium carboxymethyl cellulose‐builder systems. Practical considerations limit use of CMC to the lower concentrations, and it has been shown that at sodium carboxymethyl cellulose concentrations of 5%, or even less, builder tolerance is increased without sacrifice in soil removal properties. At CMC concentrations above 3% the soil removal properties of the ternary systems under study are increased above that of soap alone except in the case of very high builder content. Within common soap: builder ratios the whiteness retention properties of the system are substantially increased by the addition of CMC. Both soil removal and whiteness retention properties of unbuilt soap are also increased by the addition of small amounts of CMC.
Soap gels in non‐aqueous media. III. The setting time, syneresis, and gel‐strength of gels of some sodium soaps in organic solvents
Authors: Hattiangdi Gopal S. , Adarkar Shrirang P. 
Published: July 2007

Summary

The setting time, syneresis, and gel‐strength of gels of sodium palmitate, sodium stearate, and sodium oleate in toluene, xylene, cymene, pinene, chlorobenzene, bromobenzene, p‐chlorotoluene, n‐amyl, n‐ and i‐butyl, n‐ and i‐propyl, and benzyl alcohols, o‐cresol, glycerol, anisole, and phenetole, have been measured.

For gels in any given solvent the setting time and extent of syneresis decrease with different soaps in the order, NaOl>NaStr>NaP, and the gelstrength increases in the order, NaOl<NaStr<NaP. for solvents belonging to a homologous series the setting time and extent of syneresis of soap gels increase and the gel‐strength decreases as the series is ascended.

An explanation for this behavior is offered in terms of the constitutive properties of the solvent molecules.
Reactions of fatty materials with oxygen. IV.1 Quantitative determination of functional groups
Authors: Knight H. B. , Swern Daniel 
Published: July 2007

SummaryConventional analytical procedures employed in oxidation reactions for the quantitative determination of functional groups have been applied to a series of pure compounds as well as to two synthetic mixtures and to methyl oleate hydroperoxide (estimated purity, 70%). In the absence of peroxide and oxirane groups the analytical procedures are reliable. When peroxides are present, unusually high and variable values for carbonyl oxygen are obtained, and the iodine and saponification numbers are generally unreliable. Determination of hydroxyl oxygen is interfered with by large proportions of oxirane compounds but apparently not by peroxides. Determination of acid number and peroxide and oxirane oxygen is reliable in the presence of all the other functional groups investigated. Techniques for the accurate determination of functional groups when peroxide and oxirane groups are present are described.A modified procedure for the determination of carbonyl oxygen is reported.
Variation in the wax content of sunflower seed with location and hybrid
Authors: Morrison W. Herbert 
Published: July 2007

AbstractThree genetically different types of oilseed sunflower hybrids grown at six different locations were evaluated for the influence of hybrid and location on wax content of hull and oil. Analysis of variance showed that differences in the amount of hull and wax content of the hull were related to both location and hybrid. However, location and hybrid were not found significantly to influence wax content of the oil.
Gas chromatographic determination of biphenyl and phenyl ether in oil
Authors: Min D. B. , Wen J. 
Published: July 2007

AbstractOils containing 0~100 ppm biphenyl and phenyl ether were analyzed by a new gas chromatographic method. Correlation coefficients (r) between gas chromatographic peak heights and biphenyl and phenyl ether concentrations were 0.99 and 0.98, respectively. As little as 5 ppm biphenyl and phenyl ether in oils could be determined rapidly and efficiently in 90 min by this new method.
Metal salts requisite for the production of eicosapentaenoic acid by a marine bacterium isolated from mackerel intestines
Authors: Akimoto Masamichi , Ishii Tetsuya , Yamagaki Koji , Ohtaguchi Kazuhisa , Koide Kozo , Yazawa Kazunaga 
Published: July 2007

AbstractMetal salts important for the growth and 5,8,11,14,17‐ ciseicosapentaenoic acid EPA) production of a bacterium isolated from Pacific mackerel intestines were investigated at 25°C in culture media containing 1.0% peptone and 0.50% yeast extract, and the composition of an optimum culture medium was determined. This bacterium could grow in the media in which sodium chloride was the sole added inorganic component. By raising the concentration of sodium chloride from 1.2 to 2.4%, the yield of bacterial cells increased and the yield of EPA reached a maximum at 2.0% NaCl concentration. In contrast to calcium chloride, potassium chloride and magnesium chloride as second metal salts promoted the growth of this bacterium at relatively low concentrations without inhibiting the accumulation of EPA. The yield of EPA reached its maximum value of 51.9 mg/L of culture broth at 8 hr at 2.0% NaCl, 0.15% KCl and 0.16% MgCl2 concentrations. This yield of EPA was 20% greater than that obtained with Jamarin S artificial sea water.
Preparation and properties of double‐ or triple‐ chain surfactants with two sulfonate groups derived fromN‐ Acyldiethanolamines
Authors: Zhu Yun‐peng , Masuyama Araki , Kirito Yoh‐ichi , Okahara Mitsuo 
Published: July 2007

AbstractBis(sulfonate) types of amphipathic compounds with three long‐ chain alkyl groups were prepared by the reaction ofN‐ (long‐ chain acyl)diethanolamine diglycidyl ethers with long‐ chain fatty alcohols, followed by the reaction with propanesultone. The diglycidyl ethers were easily obtained from the correspondingN‐ acyldiethanolamines and epichlorohydrin in the presence of a phasetransfer catalyst. The same types of compounds with two longchain alkyl groups were also prepared from Nacetyldiethanolamine according to similar procedures. All these new double‐ or triple‐ chain surfactants were soluble in water and showed much better micelle forming and ability to lower surface tension than general types of single‐ chain surfactants with one sulfonate group. The critical micelle concentration (CMC) and γCMC values of the triple‐ chain compounds were still much smaller than those of the corresponding double‐ chain compounds with two common alkyl groups. The efficiency of adsorption at the water/air interface (pC20) of these surfactants was very high. Their foaming properties, wetting ability toward a felt chip, and lime‐ soap dispersing ability were measured.
Methods for removing detergents from waste waters
Authors: Brunner C. A. 
Published: July 2007

AbstractA number of processes have been investigated or are being investigated for removal of alkyl‐benzene sulfonate (ABS) from waste waters. These can be divided into processes applicable to launderette wastes and processes applicable to municipal waste water although there is overlap. Launderette waste treating methods include, flocculation, flotation, adsorption on activated carbon or ion exchange materials and filtration. In municipal waste water treatment any ABS removal method must be very inexpensive. Two methods that have been used to remove most of the residual ABS after conventional sewage treatment are foaming and adding of cationic detergents. Both methods are capable of removing ABS down to levels of 0.5 ppm or less. A number of other treatment methods that will remove organics, including ABS, from municipal wastes are being studied. Their costs are, in general, too high to make them applicable for ABS removal alone. Processes under study include adsorption, chemical oxidation, ion exchange, electrochemical degradation and even distillation.
An evaluation of the river die‐away technique for studying detergent biodegradability
Authors: Setzkorn E. A. , Huddleston R. L. , Allred R. C. 
Published: July 2007

AbstractThe accuracy and reproducibility of the river die‐away test has not been well defined. This information is required to establish the validity of observed differences in degradation behavior.The present paper presents data on the accuracy and repeatability of the methylene blue analytical procedure using both the standard method and the automated 舠AutoAnalyzer舡 version of the methylene blue method.Data are also presented showing reproducibility of the biodegradation curves obtained by replicate analysis of a single detergent under 1) identical die‐away conditions, and 2) different conditions obtained by die‐away studies in various river waters.The effect of detergent mol wt and microbial adaptation to the test substance on the degradation pattern is also discussed.
Soaps of monohydroxystearic acid in syndet compositions
Authors: Osipow L. I. , Rosenblatt William , Snell F. D. 
Published: July 2007

AbstractSoaps of monohydroxystearic acid, prepared by sulfation of oleic acid followed by hydrolysis, have been evaluated in syndet compositions. They can be used to replace a substantial proportion of the synthetic surfactant in both liquid and solid detergent compositions without loss of detergent efficiency or foaming properties. In contrast, sodium stearate and sodium oleate adversely affect performance. Compatibility is improved when these hydroxystearate soaps are incorporated in built liquid compositions. Since these materials exhibit the usual response of soaps to pH change and to divalent cations, there is complete assurance that they will be inactivated in ground water as well as in sewage treatment plants.
Peroxidizing and carotene bleaching substances in bacon adipose tissue
Authors: Reiser Raymond 
Published: July 2007

Summary and ConclusionThe peroxidation activity of hemoglobin solutions was studied for the effects of concentration of hemoglobin and heat. The carotene bleaching activity of hemoglobin was studied for the effects of pH, concentration of hemoglobin, concentration of carotene, time, heat, and poisons. These observations were compared to similar studies of hemoglobin free extracts of salt cured bacon fatty tissue. It was found that hemoglobin activity is not influenced by boiling but that there is a heat labile factor in hemoglobin free extracts. Evidence is presented that the hemoglobin free extracts contain at least two principles which may be responsible for the rapid development of rancidity in bacon and one inhibitor.