bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intermediate Hamiltonian via Glazman's splitting and analytic perturbation for meromorphic matrix‐functions
Authors: Mikhailova Anna B. , Pavlov Boris S. , Prokhorov Lev V. 
Published: August 2007

AbstractWe consider the spectral problem for the Schrödinger operator ℒ︁ on a quantum network, represented as a union of a finite number of quantum wells and finite or semi‐infinite straight quantum wires connecting them to each other and to infinity. The absolutely continuous spectrum of the Schrödinger operator, with real piecewisecontinuous potential on the wells and constant potential on the wires, has a band structure defined by the geometry and the potentials on the semi‐infinite wires. We split the Schrödinger operator, depending on the Fermi level Ë, into an orthogonal sum of two operators ℒ︁ → lΛ ⊕ LΛ, which have the complementary branches of the absolutely continuous spectra coincident, counting multiplicity, respectively with the unionsΣ = ∪σopen , Σ = ∪σclosed of absolutely continuous branches σ = [λσ , ∞) of open and closed channels in the semi‐infinite wires, with thresholds λσ < Λ, λσ > Λ, respectively. This enables us to reduce the problem of evaluation of the scattering matrix on the network to the solution of a finite linear system, involving the Dirichlet‐to‐Neumann map of the intermediate Hamiltonian LΛ. We calculate the intermediate Dirichlet‐to‐Neumann map approximately, for thin networks, based on the classical DN‐map of the relevant Schrödinger operator on the compact part of the network. To this end we develop a modified analytic perturbation procedure for meromorphic operatorfunctions with small one‐dimensional residues. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Silole‐Containing Polymers: Chemistry and Optoelectronic Properties
Authors: Chen Junwu , Cao Yong 
Published: August 2007

AbstractIn this review, the synthesis and optoelectronic properties of various π‐conjugated‐, σ‐conjugated‐, pendanted‐, and hyperbranched or dendritic silole‐containing polymers (SCPs) are described. So far, substituted silole, dibenzosilole, dithienosilole, and bis‐silicon‐bridged stilbene have been incorporated into SCPs. The tunable bandgaps from 4.0–1.55 eV, variable fluorescent colors from UV to blue, green, and red (RGB) light, fluorescent chemo‐sensors for 2,4,6‐trinitrotoluene (TNT)‐type explosives, aggregation‐induced emission, efficient electroluminescence emissions for RGB lights, phosphorescent hosts with high triplet energy level, efficient solar cells, stable field‐effect transistors with high hole mobility in air, and attenuation of strong laser power, are the important features of SCPs.magnified image
Beitrag niedriger Lastamplituden zur Ermüdungsschädigung von 0,15 %C Stahl
Authors: Mayer H. , Stojanovic S. , Ede C. , Zettl B. 
Published: August 2007

AbstractDie Wöhlerkurve von 0,15 %C Stahl zeigt eine Dauerfestigkeit. Zweistufen Blockprogrammversuche dienen dazu, den Einfluss einer Vielzahl von Lasten unterhalb der Dauerfestigkeit auf die Ermüdungsschädigung zu untersuchen. Liegt die hohe Stufe im Zweistufenkollektiv mehr als ca. 15 % über der Dauerfestigkeit, dann tragen Schwingspiele unterhalb der Dauerfestigkeit wesentlich zur Ermüdungsschädigung bei. Untersuchungen des Risswachstums mit Zweistufenkollektiven zeigen, dass die Ursache dafür die Beschleunigung des Ermüdungsrisswachstums durch eine Vielzahl an niedrigen Lasten ist. Liegen die hohen Stufen im Zweistufen Ermüdungsversuch weniger als ca. 15 % oberhalb der Dauerfestigkeit, dann zeigt sich ein positiver Einfluss einer Vielzahl an niedrigen Lasten. Unter diesen Bedingungen können im Zweistufen Blockprogramm eine weitaus größere Zahl an Lastamplituden ohne Bruch ertragen werden, als mit einer Miner‐Rechnung vorhergesagt. Rissausbreitungsuntersuchungen zeigen, dass unter diesen Bedingungen für die hohe Last zahlreiche niedrige Amplituden zu einem Stoppen des Ermüdungsrisswachstums führen.
Distal lesion of the lateral femoral cutaneous nerve
Authors: Kushnir Mark , Klein Colin , Kimiagar Yitzhak , Pollak Lea , Rabey Jose M. 
Published: August 2007

AbstractWe report three patients with a typical clinical picture of unilateral meralgia paresthetica in whom routine nerve conduction studies were normal. However, cortical somatosensory evoked potentials were absent after lateral femoral cutaneous nerve (LFCN) stimulation on the affected side. After stimulation of the LFCN in the anterosuperior iliac spine (ASIS) region and recording the responses distal to conventional sites (20 cm from the ASIS), sensory nerve action potentials (SNAPs) were absent in the symptomatic leg, but present in the normal leg. We suggest that thigh paresthesias may be caused by a distal LFCN lesion. Eliciting this requires recording SNAPs distal to conventional sites. Muscle Nerve, 2007
Capacity allocation to sales agents in a decentralized logistics network
Authors: Demirag Ozgun Caliskan , Swann Julie L. 
Published: August 2007

AbstractMany logistics systems operate in a decentralized way, while most optimization models assume a centralized planner. One example of a decentralized system is in some sea cargo companies: sales agents, who share ship capacity on a network, independently accept cargo from their location and contribute to the revenue of the system. The central headquarters does not directly control the agents' decisions but can influence them through system design and incentives. In this paper, we model the firm's problem to determine the best capacity allocation to the agents such that system revenue is maximized. In the special case of a single‐route, we formulate the problem as a mixed integer program incorporating the optimal agent behavior. For the NP‐hard multiple‐route case, we propose several heuristics for the problem. Computational experiments show that the decentralized system generally performs worse when network capacity is tight and that the heuristics perform reasonably well. We show that the decentralized system may perform arbitrarily worse than the centralized system when the number of locations goes to infinity, although the choice of sales incentive impacts the performance. We develop an upper bound for the decentralized system, where the bound gives insight on the performance of the heuristics in large systems. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
Thermal and mechanical properties of electrospun PMMA, PVC, Nylon 6, and Nylon 6,6
Authors: Carrizales Clarisa , Pelfrey Sean , Rincon Roman , Eubanks Thomas M. , Kuang Anxiu , McClure Michael J. , Bowlin Gary L. , Macossay Javier 
Published: August 2007

AbstractPoly(methyl methacrylate) (PMMA), poly(vinyl chloride) (PVC), Nylon 6, and Nylon 6,6 have been electrospun successfully. The nanofibers have been characterized by scanning electron microscopy (SEM), confirming the presence of bead free and fiber‐bead free morphologies. Thermogravimetric analysis (TGA) indicated differences between the thermal stability of PMMA nanofibers and PMMA powder. However, no significant differences were observed between the starting physical form (powder or pellet) of PVC, Nylon 6 and Nylon 6,6, and their corresponding electrospun nanofibers. Differential scanning calorimetry (DSC) demonstrated a lower glass transition temperature (Tg) and water absorption for PMMA electrospun nanofibers. Furthermore, electrospun Nylon 6 and Nylon 6,6 had a slight decrease in crystallinity. Tensile testing was performed on the electrospun nanofibers to obtain the Young modulus, peak stress, strain at break, and energy to break, revealing that the non‐woven mats obtained had modest mechanical properties that need to be enhanced. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis, crystallinity and degradation properties of biodegradable poly[(sebacic anhydride)‐co‐caprolactone] triblock copolymers
Authors: Miao Hui , Hao Jianyuan , Liu Yan , Liu Yu , Deng Xianmo 
Published: August 2007

AbstractBACKGROUND: A series of novel biodegradable poly[(sebacic anhydride)‐co‐caprolactone] (PSA‐co‐PCL) triblock copolymers were prepared by melt condensation of acylated PSA and monofunctional hydroxyl‐terminated PCL prepolymers. These copolymers could be used as novel drug delivery carriers with expected good drug permeability due to the PCL component. The degradation rate and mode can be modulated by varying the ratio of monomers in the copolymer.RESULTS: The homopolymers and copolymers were characterized using 1H NMR, gel permeation chromatography and differential scanning calorimetry (DSC). 1H NMR confirmed the formation of triblock copolymers that comprise a middle PSA block and two side PCL blocks. DSC revealed that the melting temperature and degree of crystallinity for both sebacic anhydride (SA) and caprolactone (CL) components are strongly composition dependent, implying the hindrance effect of the two components on the crystallinity. In vitro degradation experiments showed that the mass loss is significantly accelerated for samples in base buffer solution and more rapid for the copolymers with a higher SA content. Scanning electron microscopy revealed that for SA‐rich copolymer, PSA(80 wt%)‐co‐PCL, surface erosion dominated the degradation mode of the sample. In contrast, for CL‐rich copolymer, PSA(20 wt%)‐co‐PCL, a micropore structure developed at a degradation time of 155 h along the edges of the sample, owing to the hydrolysis of SA.CONCLUSION: It is concluded that the rate and mode of degradation of these copolymers can be tuned by varying the composition of the copolymers. Copyright © 2007 Society of Chemical Industry
Composite TiOx/Hydrocarbon Plasma Polymer Films Prepared by Magnetron Sputtering of TiO2 and Poly(propylene)
Authors: Drabik Martin , Hanus Jan , Kousal Jaroslav , Choukourov Andrei , Biederman Hynek , Slavinska Danka , Mackova Anna , Pesicka Josef 
Published: August 2007

AbstractThis study describes the preparation and the properties of TiOx/hydrocarbon plasma polymer composite films. Films are prepared by simultaneous sputtering in argon from two balanced magnetrons equipped with TiO2 and PP targets. The resulting films exhibit a wide range of properties in dependence on the preparation conditions – primarily on the ratio of the deposition rates r(TiOx)/r(PP) and thus the power delivered to the magnetrons. The deposition process is monitored by optical emission spectroscopy. The composition and morphology of the composite films have been analyzed by means of RBS/ERDA, FTIR, AFM, and TEM. Optical properties of the films are studied in the UV and visible range of the spectrum. Finally, an attempt has been made to express the amount of inorganic phase present in the organic matrix in terms of a filling factor.magnified image
Tumour preventive effect of Aloe vera leaf pulp lectin (Aloctin I) on Ehrlich ascites tumours in mice
Authors: Akev Nuriye , Turkay Gulhan , Can Ayse , Gurel Aydin , Yildiz Funda , Yardibi Hasret , Ekiz Elif Ergul , Uzun Hafize 
Published: August 2007

AbstractIn this study, the prophylactic effect of the main lectin present in Aloe vera leaf pulp extract (Aloctin I) was assayed against Ehrlich ascites tumours in mice. The lectin administered prophylactically before tumour implantation regressed tumour size, however, this activity was less potent than that of the A. vera leaf pulp extract previously shown in our laboratory. Accordingly, serum sialic acid and tumour necrosis factor alpha (TNFα) levels, chosen as tumour markers, were decreased significantly by the prophylactic administration of the lectin. The increase in spleen and thymus weights in the group given only Aloctin I, could be explained by the immunomodulatory and mitogenic effects of lectins. These findings, along with lymphoid hyperplasia observed in spleen and thymus, suggest that the tumour preventive effect of Aloctin I could be due to its immunomodulatory activity. Copyright © 2007 John Wiley & Sons, Ltd.
New tertiary amine‐based surface active polymers
Authors: Schmolka Irving R. , Seizinger Reinhold K. 
Published: August 2007

AbstractSurface active polymers with molecular weight ranging from 5600 up to 30,000 were synthesized by the oxyethylation of polyoxpropylene glycol adducts of ethylene diamine, which range in molecular weight from 4750 up to 6750. The toxicological properties of some of these new nonionics indicated that they would be nontoxic when used in contact with the skin and scalp. Their typical physical properties such as wetting, emulsifying, foaming and thickening are reported. A variety of cosmetic formulations has been prepared utilizing these new nonionic surface active polymers. This illustrates their versatility when used in products as diverse as a floating bath oil, an antiperspirant gel, a cold cream and a sun screen lotion.
Influence of various surfactants on the antimicrobial activity of bromsalans and other ring‐halogenated substances
Authors: Molnar Nicholas M. 
Published: August 2007

AbstractTest methods used in the assessment of activity are discussed, utilizing the gradient plate dilution technique of Curry (1) for screening work. The various classes of surfactants studied included anionics, nonionics, amphoterics, and cationics.A study was made in vitro of the influence of these surface‐active agents on five antimicrobial agents. Based upon these tests it appears that, in general, Temasepts I, II, and IV show greater activity and a broader spectrum than G‐11 and TCC. This is particularly evident in the presence of conventional soap and the newer non‐soap bars.An interesting pattern of results was observed when nonionic BC720 was used in the system. All of the antimicrobial agents were equal in activity againstStaphylococcus aureus, Escherichia coli, andCandida albicans, but Temasept I showed the highest activity againstPityrosporum ovale andAspergillus niger, with TCC occupying an intermediate position.The cationic vehicles alone, in addition to any possible enhancement of the ring‐halogenated aromatics, contribute significantly in the system to inhibit all of the test strains.With the amphoteric vehicles, the antimicrobial agents for the most part were equally effective, with G‐11 being slightly less effective. In striking contrast, the three Temasepts showed far greater activity againstP. ovale, C. albicans, andA. niger, especially in Miranol CS.The data presented may be utilized for the formulation of fabric softeners, and the tests employed aid in the selection of the proper surfactant for textile and skin applications. The work demonstrates that in any technical appraisal of the antimicrobial potency of a compound, the influence of the surfactant vehicle is of paramount importance.
Alcohol ether sulfates in shampoos
Authors: Watanabe Henry , Groves W. L. 
Published: August 2007

AbstractMono‐, di‐ and triethanolamine sulfates of several different molecular weight alcohol ether sulfates were formulated into shampoos. The ethylene oxide content of the alcohol ethoxylates varied from about 20 to 60%, although 40% was usual. The shampoo formulation was 20% active ether sulfate and 5% foam stabilizer. Lauric diethanolamide and amine oxides were used as foam stabilizers.The shampoos were tested for quality and quantity of foam, viscosity and cloud point. Although no “hair effects” tests were run, a limited home use test was made.Alcohol ether sulfate shampoos are equal or superior to several popular commercial products on the basis of a laboratory foam test. They are comparable in foam to alcohol sulfates in similar formulations. Cloud points of these shampoos were generally good. Amine oxide foam stabilizers reduced the cloud point more than the amide. Viscosities of the shampoos were readily controllable. Although the choice of alkanolamine, alcohol molecular weight and degree of ethoxylation had some effect on these properties, none were highly critical; this allows considerable leeway in their selection. The home use tests assured us that these shampoos were not obviously deficient in the desired “hair effect” properties. The literature records that alcohol ether sulfates are preferred to alcohol sulfates for low skin and eye irritation.By varying the free oil (unsulfated ethoxylate) content and making the proper choice of ether sulfate and foam stabilizer, bright and clear liquid shampoos with viscosities from about 10 centipoise to over 50,000 centipoise were made. The latter are essentially gels. Paste shampoos were also made from these ether sulfates.
Isomeric phenylstearic acids and related compounds: Composition and partial separation
Authors: Smith F. D. , Stirton A. J. , Dooley C. J. 
Published: August 2007

AbstractReaction of benzene with oleic acid, methyl oleate, oleyl alcohol and oleonitrile, catalyzed by AlCl3, yielded the expected phenylstearic acid or the related ester, alcohol or nitrile as a viscous oil which failed to crystallize.Gas liquid chromatography of the ketone fraction obtained by CrO3 oxidation showed 12 position isomers, with the phenyl group at C atoms 6–17, for phenylstearic acid, methyl phenylstearate and phenylstearonitrile. Oxidation of phenyloctadecanol revealed one more isomer, (5‐phenyloctadecanol). Distribution of isomers was quite similar for the acid, ester, alcohol and nitrile. Repeated low temperature crystallization from acetone and other solvents separated the 17‐, 16‐ and 15‐phenyl isomers in a pure state. Initial crystallization gave the 17‐phenyl isomer, except for phenylstearic acid. In this case, contrary to our previous report, the product from initial crystallization was 16‐phenylstearic acid.
Variability of degree of high order compositeness in fats from the same biological species: Fats from geographic varieties ofpongamia glabra, Nerium thevetifolium andMoringa pterygosperma
Authors: Kartha A. R. S. , Upadhyay G. S. 
Published: August 2007

AbstractSeed fats from four geographic varieties ofP. glabra (Sm 20.2, 27.1, 25.2 and 24.7), three ofN. thevetifolium (Sm 33.5, 36.3 and 33.1) and two ofM. pterygosperma (Sm 23.2 and 20.6) showed high order compositeness (HOC) indices of GS3nil, GS2U +5.2, −3.1, +5.2 and +9.0, GS3nil, GS2U +0.9, +7.0 and +2.0 and GS3nil, GS2U +2.0 and +7.3 respectively. Since geographic varieties are morphologically indistinguishable no fixed relationship can any longer be expected between the proportions of acids and glycerides in different specimens of fat from the same biological variety. Prediction of glyceride structures of different specimens of fat from the same variety can hence be made only to the extent of HOC ranges just as in the case of fats from different varieties or species.Fats from geographic varieties belonging to different biological species show different kinds of relationships between the component saturated and unsaturated acids. No quantitative or even qualitative correlation exists between the HOC indices and the proportions of saturated acids in fats from geographical varieties belonging to the same biological source.
Neutron activation analysis and its application to the analysis of food products
Authors: Guinn Vincent P. 
Published: August 2007

AbstractHigh‐flux thermal‐neutron activation analysis (NAA) is an extremely sensitive means of quantitatively determining most of the elements of the periodic system. The usual limits of detection, for 75 of the elements, in the absence of appreciable interferences, range from picograms (for some elements) to as high as micrograms (for less sensitive elements). A typical element can be determined down to as low as a nanogram. This high sensitivity enables one to analyze food products, for example, for numerous trace‐level elements that may be present: whether natural or added beneficial essential trace elements, or deleterious elements introduced from pesticide residues (such as Br, As and Hg), or from processing (such as Cr, Sn, Sb and Cu). Studies to be reported include the nondestructive determination of Hg in foodstuffs down to levels as low as 0.01 ppm, and of Br in foodstuffs down to about 0.1 ppm. With radiochemical separations, these detection limits can both be extended to 0.001 ppm, if needed. By combination with paper chromatographic or solvent extraction techniques, phosphorus‐ and halogen‐containing pesticides can be sensitively determined. The NAA method can also be used to advantage at element levels much higher than trace levels, and in such cases the very high neutron flux of a nuclear reactor may not be necessary. For example, even with a small 14 Mev neutron generator, the nitrogen content of foodstuffs can be determined nondestructively, rapidly and accurately, down to levels of about 100 ppm. These determinations can also be made on‐line, in food processing plants.
Computer aided spectroscopy
Authors: Crisler Robert O. 
Published: August 2007

AbstractTechniques are being developed which have as their objective improvement in the accuracy of infrared absorbance measurements and more exact recording of the true band shapes. From these improved spectra, accurate quantitative parameters are being obtained which can supplement or even supplant the present chart recordings as the fundamental spectral representations. These techniques include methods for processing spectra to eliminate most of the instrumentally introduced artifacts and to resolve the corrected spectra into algebraic representations in the form of sums of distribution functions. The consequences of the increasing use of these techniques will be to improve significantly our ability to do both qualitative and quantitative analysis.
Glycolipids isolated from ginkgo nuts(Ginkgo biloba) and their fatty acid compositions
Authors: Kameyama Haru , Urakaml Chieko 
Published: August 2007

AbstractThe total amount of glycolipids isolated fromGinkgo biloba nut was 3.12% of crude lipids, and the largest fraction of the glycolipids was digalactosyldiglyceride 64.1%, followed by mono‐galactosyldiglyceride 31.2% and cerebroside 4.7%. Chief fatty acids present in the former two were oleic and linoleic acids, while the main compo‐nent amounting to 85% of total fatty acids in the last fraction was α‐hydroxypalmitic acid. The sugar component in cerebroside was glucose, and its long chain base was found to be similar in structure with octadecasphingadiene that had been isolated from oyster glycolipids. The major compound in the cerebroside fraction, therefore, is considered to be N‐α‐hydroxypalmitoyl‐glucosyloctadecasphingadiene.
Novel technique for the analysis of volatiles in aqueous and nonaqueous systems
Authors: Legendre M. G. , Fisher G. S. , Schuller W. H. , Dupuy H. P. , Rayner E. T. 
Published: August 2007

AbstractA simple, efficient, external inlet assembly is described for analyzing volatile components in raw and processed foods by direct gas chromatography and mass spectrometry. The device comprises three sections: a sample inlet, a condenser, and a six‐port rotary valve. The versatility and effectiveness of this assembly is demonstrated by the analysis and identification of volatiles from diverse food products as salad oils, vinegar, and corn‐soy food blends. The procedure is rapid, efficient, and offers the following desirable features: it is compatible with all commonly used chromatographs and can accomodate samples of different size; sample volatiles are obtained without use of prior enrichment techniques, at ambient or elevated temperatures; uniform heating enhances volatiles elution, thereby improving sensitivity; moisture and air are removed to facilitate mass spectral analysis; the closed nature of the system minimizes loss of low molecular weight volatiles during elution, thus producing a highly reliable pro‐file of volatiles.
Pilot‐plant scale grinding and pressing of jojoba seeds
Authors: Miller R. E. , Edwards R. H. , Kohler G. O. 
Published: August 2007

AbstractJojoba seeds were successfully milled at ambient temperature using a modified 8 in. single disk attri‐tion mill. Rates to 4000 lb/hr at low energy input (1.7 kwh/ton) were achieved. The oil was expressed with a laboratory screw press at yields from 27. to 33.6%. Multiple linear regression analysis showed the oil yield to be a function of the motor amperage and feed moisture content. The press throughput rate was a function of the motor amperage and the amount of fine and coarse particles in the milled feed.