bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laser Flash Photolysis in High-Speed Photopolymer Coating Layers: Effects of Incorporating Dimethyl Phthalate as a Plasticizer into Coating Formulation
Authors: Urano Toshiyuki , Nagasaka Hideki , Shimizu Makoto , Takahara Shigeru , Yamaoka Tsuguo 
Published: June 2006

Abstract
The sensitization mechanisms of ketocoumarin dyes with a radical-generating reagent, 10,10′-carbonylbis[1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one] (KCD-J), 7,7′-bis(diethylamino)-3,3′-carbonyldicoumarin (KCD-DA) with 3,3′,4,4′-tetrakis(t-butyldioxycarbonyl)benzophenone (I) in poly(methyl methacrylate) film containing dimethyl phthalate (DMP) as a plasticizer have been investigated by laser flash photolysis using a total reflection cell. The fluorescence of the dyes was efficiently quenched by I in PMMA containing 50 wt% of DMP (film A) against total solid with static quenching distances of 12.5 and 12.7 Å for KCD-J and KCD-DA. The static quenching distance was around 1.5 times longer than that in PMMA. The decay time of the triplet in a film A was slightly quenched by I with a kq of less than 1.5 × 106 mol−1 dm3 s−1 for KCD-J and KCD-DA.
These results show that a static singlet sensitization from the fluorescent excited dyes to I is the predominant process in film A, suggesting the same predominant static singlet sensitization process in a PMMA film containing acrylate monomer, and the static quenching distance is increased by incorporation of DMP into PMMA film.
Sequence Effects on Helix-Sheet Conformational Transitions of Designed Amphiphilic Peptides
Authors: Fukushima Yasumasa 
Published: June 2006

Abstract
Four 18-residue amphiphilic peptides were designed and synthesized, and their helix-sheet conformational transitions were investigated by circular dichroism (CD) in aqueous solution at different pH, peptide concentration and ionic strength as well as in a water/HFIP mixture. The α-helical conformations existed as monomeric states, while the β-sheet structures were formed by the aggregation of approximately 6 monomeric peptides for Peptide I, II, and III. The conformational transitions were provided by the self-association and dissociation of each peptide. The aggregated β-sheet structures would be stabilized by intermolecular hydrophobic interactions and complementary ionic bonds in addition to the conventional hydrogen bonds. In contrast, the formation of α-helical conformations would be caused by intramolecular electrostatic interactions between charged residues and the intrinsic high α-helix propensities of constituent amino acids in addition to hydrogen bonds. These peptides could be useful models for studying the factors governing the stability of secondary and tertiary structures as well as conformational transitions for comprehending the principles of how proteins fold into native states.
Synthesis, Structure, and Some Reactions of (2,4,6-Tri-t-butyl)thiobenzaldehyde, the First Stable Aromatic Thioaldehyde
Authors: Ishii Akihiko , Ishida Takashi , Kumon Naoko , Fukuda Nobuo , Oyama Hiroyuki , Inamoto Naoki , Iwasaki Fujiko , Okazaki Renji 
Published: June 2006

Abstract
The title compound 1 was synthesized by the reaction of 2,4,6-tri-t-butylphenyllithium with O-ethyl thioformate or that of 2,4,6-tri-t-butylbenzaldehyde hydrazone with disulfur dichloride in the presence of triethylamine. The thioaldehyde 1 is a purple crystalline compound which is thermally quite stable; only around 200 °C it underwent intramolecular cyclization to give 6,8-di-t-butyl-3,4-dihydro-4,4-dimethyl-1H-2-benzothiopyran 9. The X-ray crystallographic analysis of 1 revealed that the thioformyl group is almost perpendicular to the aromatic ring. The reaction of 1 with 1-cyano-1-methylethyl radicals afforded 9, while that with t-butyl radicals gave 1,3,5-tri-t-butyl-2-t-butylthiomethylbenzene and t-butyl 2,2-dimethyl-1-(1,3,5-tri-t-butylbicyclo[2.2.0]hexa-2,5-dien-2-yl)propyl sulfide in addition to 9. Some Grignard reagents and organolithiums reacted with 1 gave carbophilic, thiophilic, double addition products and some others depending on the kind of the organometallic reagents. Hydrazine and butylamine reacted with 1 very readily to give the corresponding hydrazone and imine, respectively.
Synthesis and Properties of High-Molecular-Weight Polypeptides Containing Tryptophan II. Copolypeptides of Tryptophan with Various Amino Acids
Authors: Uchida Chieko , Iizuka Yasuko , Ohta Eido , Wakamatsu Kaori , Oya Masanao 
Published: June 2006

Abstract
High-purity N-carboxyl l-tryptophan anhydride (l-4-indoylmethyl-2,5-oxazolidinedione) was synthesized in good yield. Copolypeptides with a random sequence of l-trypophan (Trp) with glycine (Gly), l-alanine (Ala), l-α-amino-n-butyric acid (Abu), l-n-valine (Nval), l-n-leucine (Nleu), l-leucine (Leu), l-γ-methylglutamate (Glu(OMe)), and l-methionine (Met) were synthesized by the copolymerization of the corresponding N-carboxy-α-amino acid anhydrides (NCA) in solution. The rate of polymerization of Trp NCA was less than that of the other amino acid NCAs. The helix contents of the formed copolypeptides, estimated by the circular dichroism (CD) spectra, were remarkably decreased at a content of about 8% of Trp involved in poly(Trp-co-Nval) (poly(Trp,Nval)), poly(Trp-co-Leu) (poly(Trp,Leu)), poly(Trp-co-Nleu) (poly(Trp,Nleu)), and poly(Trp-co-Glu(OMe)) (poly(Trp,Glu(OMe))), but was not decreased at that percentage in poly(Trp-co-Met) (poly(Trp,Met)).
Dye–Surfactant Interaction: Role of an Alkyl Chain in the Localization of Styrylpyridinium Dyes in a Hydrophobic Force Field of a Cationic Surfactant (CTAB)
Authors: Mishra Amaresh , Patel Sanjukta , Behera Rajani K , Mishra Bijaya K , Behera Gopa B 
Published: June 2006

Abstract
The interaction of a number of cationic dyes (I) with a varying number of methylene groups (Cn) in the alkyl chain attached to pyridyl nitrogen with a cationic surfactant (CTAB) assembly is reported. The binding constant of the dyes (C5 to C18) with the micelle have been calculated, and are found to increase with increasing carbon chain. A plot of the binding constant vs. the chain length shows a curve with a maximum for C16, which is attributed to a compatibility factor. From studies of the electronic and emission spectra it is proposed that a micelle has a hydrophobic force field and that the dyes are localized in various pockets of the field.
Molecular Structures of Zinc Complexes with Bisbenzimidazole Ligands in Crystals and the Kinetics of Ligand-Exchange Reactions in Their Solutions
Authors: Ogawa Kazuya , Nakata Kou , Ichikawa Kazuhiko 
Published: June 2006

Abstract
Zinc complexes with bisbenzimidazole, [ZnL(PhCOO)2] 1, [ZnLCl2] 2, and [ZnL2]2+ 3, have been synthesized, where L = 2,2′-thiodimethylenebis(benzimidazole). Their molecular structures were determined based on X-ray crystal structure and extended X-ray absorption fine structure (EXAFS) analyses. The molecular structure of 1·1.5DMF shows a distorted tetrahedral geometry around Zn(II) coordinated by each nitrogen atom of two benzimidazolyl groups and each oxygen atom of two benzoate ions. In solutions of 2 or 3·(ClO4)2 the same chemical species, [ZnLCl2] or [ZnL2]2+, exist as in the coordination structure around zinc in each crystal. The combination of 13C NMR data with the most probable molecular structures of zinc complexes in 1, 2, and 3, determined by X-ray crystal structure and EXAFS analyses, allowed us to assign the two different chemical species, [ZnL(PhCOO)2] and [ZnL2]2+, as the major and minor components, respectively, in a solution of 1. A kinetic study of the ligand-exchange reaction between PhCOO− and L was provided us with the lifetimes of the chemical species of [ZnL(PhCOO)2] and [ZnL2]2+: 66 ms and 10 ms at −10 °C, respectively. The major species produced by a zinc-assisted supramolecular process in solution is the same type of chemical species [ZnL(PhCOO)2] as in the coordination structure around zinc in the crystal of 1·1.5DMF. The ESI mass spectra of a solution of 1, 2, and 3·(ClO4)2 supported the chemical species of [ZnL(PhCOO)2], [ZnL2]2+, and [ZnLCl2] in solution.
Photothermal Expansion of Droplets in Emulsions Detected by the Transient Grating Method
Authors: Tanzawa Kazunari , Hirota Noboru , Terazima Masahide 
Published: June 2006

Abstract
A nonlinear optical effect due to the thermal energy after the photoexcitation of a light-absorbing chromophore or a metal ion contained in micro droplets (oil in water (O/W) and water in oil (W/O)) was investigated by the time-resolved transient grating method. The temporal profiles of the diffusive components of the thermal grating signals are very different from that observed in a homogeneous solution, and also depend on the emulsion systems. The profiles were consistently analyzed in terms of the droplet heating, thermal expansion, and subsequent cooling process. The size of the droplets determined from this analysis agrees with that from the dynamic light scattering method.
Reactions of N(22D) with Alkane Hydrocarbons to Produce NH(X 3Σ−)
Authors: Umemoto Hironobu , Kimura Yuki , Asai Takashi 
Published: June 2006

Abstract
Ground state NH radicals could be detected as products of the reactions of N(22D) with simple alkane hydrocarbons. N(2D) was produced by two-photon dissociation of NO, while NH (X 3Σ−) was detected by laser-induced fluorescence. The nascent vibrational population ratio, NH(v″ = 1)/NH(v″ = 0), was determined to be 0.6, 0.5, 0.5, and 0.5 for CH4, C2H6, C3H8, and C(CH3)4, respectively. These ratios are smaller than that for H2, 0.8, but much larger than the prior ones. The nascent rotational state distributions of NH(X 3Σ−, v″ = 0) were determined for CH4, C2H6, and C3H8. The distributions were much hotter than the prior ones and showed little dependence on the complexity of the hydrocarbons. This suggests that the intermediate complexes which lead to the production of NH are short-lived and decompose before intramolecular vibrational redistribution (ivr). The yields for the production of NH(v″ = 0) for heavy alkanes were smaller than that for CH4. There must be exit channels other than NH production, such as C–C bond cleavage processes.
Structures and Magnetic Properties of Dinuclear Vanadium(III) Complexes with Alkoxo Bridge
Authors: Kanamori Kan , Yamamoto Kaori , Okayasu Takako , Matsui Naoto , Okamoto Ken-ichi , Mori Wasuke 
Published: June 2006

Abstract
Several dinuclear vanadium(III) complexes were prepared using a heptadentate dinucleating ligand containing a bridging alkoxo group. The structures of [V2(dpot)(m-hbza)(H2O)2]·H2O (1b), [V2(bza)(OH)(tphpn)(H2O)2]Cl3·8H2O (2), and [V2(hpnbpda)2]·12H2O (3a) were determined by X-ray crystallography (dpot: 2-oxo-1,3-diaminopropane-N,N,N′,N′-tetraacetate, m-hbza: m-hydroxybenzoate, bza: benzoate, tphpn: N,N,N′,N′-tetrakis(2-pyridylmethyl)-2-oxo-1,3-propanediamine, hpnbpda: N,N′-bis(2-pyridylmethyl)-2-oxo-1,3-propanediamine-N,N′-diacetate). Each vanadium(III) center of 1b adopts a distorted octahedral structure, and the two vanadium centers are bridged by an alkoxo group of dpot and a carboxylato group of m-hbza bridge. Each vanadium center of 2 and 3a, however, takes a heptacoordinate structure. The coordination polyhedron of 2 can be regarded as a capped octahedron, while that of 3a as a pentagonal bipyramid. The two vanadium(III) centers are ferromagnetically coupled in 1b (J = 23.7 cm−1) and 2 (J = 14.6 cm−1), whereas in 3a they are antiferromagnetically coupled (J = −35.2 cm−1). The electrochemistry of the dpot and hpnbpda complexes has also been investigated.
Measurements and Monte Carlo Calculations of Gamma and Neutron Flux Spectra Inside and Behind Iron/Steel/Water Configurations
Authors: Boehmer B , Konheiser J , Noack K , Rogov A , Stephan I , Hansen W , Hinke D , Unholzer S , Grantz M , Mehner H-C 
Published: June 2006

Abstract
Gamma and neutron flux spectra were measured inside and behind various combined iron, steel, and water slabs, which were set up in the radial beams of the zero-power training and research reactors Ausbildungskernreaktor of the Technical University Dresden and Zittauer Lehr- und Forschungsreaktor of the University of Applied Sciences Zittau/Goerlitz. The measurements were carried out with a liquid NE-213 scintillation spectrometer in the energy ranges 0.23–10 MeV for photons and 1–20 MeV for neutrons. These experiments were simulated with the Monte Carlo transport codes mcnp-4c2 and tramo. With mcnp the point-wise energy representation of the nuclear data from endf/b-vi library, release 8, was used. For tramo effective group cross sections were prepared by means of njoy from the same data library. The paper describes the experiments and calculations and presents and compares some results.
Spallation Radiation Damage Calculations and Database: Cross-Section Discrepancies between the Codes
Authors: Lu Wei , Wechsler MS , Ferguson PD , Pitcher EJ 
Published: June 2006

Abstract
A radiation damage database at NCSU is described that contains, at present, cross sections for damage energy, displacements, helium, and hydrogen. For neutrons and protons at 20-3200 MeV energies, the targets include 23 target elements from Mg to U and eight practical alloys. The underlying calculations employ Bertini, ISABEL, and CEM2k intranuclear cascade models as provided within MCNPX, three level-density formulations (GCCI, HETC, and Jülich), and multistage pre-equilibrium model (MPM) on and off. The database also includes radiation damage cross sections for lower-energy neutrons and protons, as obtained from LA150, SPECTER, ENDF, and SRIM. Examples of the database contents are provided with regard to damage energy and displacement cross sections for neutrons on Al, Fe, and W. Also, neutron flux and displacement rate calculations are described for neutrons on Fe and the 316 stainless steel mercury container vessel at SNS. In addition, discrepancies between the codes are discussed.
The Role of Objective Plane Angulation on the Mandibular Image Using Cross-Sectional Tomography
Authors: Naitoh Munetaka , Katsumata Akitoshi , Kubota Yukinobu , Okumura Shinji , Hayashi Hisashi , Ariji Eiichiro 
Published: June 2006

Abstract
Cross-sectional jaw images in the buccolingual direction obtained by conventional or computerized tomography are used in the image diagnosis of dental implant treatment. This study was performed to clarify the subjective image quality of the mandibular depiction by shifting the angles of the tomographic objective plane. A panoramic machine with a linear tomographic function was used to obtain cross-sectional tomographic images on bilateral first molar regions of 10 dried human mandibles. The angles of tomographic objective planes were shifted horizontally within a range of ±20° at intervals of 5° from the tomographic objective plane, which was automatically determined. The image qualities of 4 anatomical structures—alveolar crest, buccal and lingual cortical bone, and mandibular canal—were subjectively scored on a 5-point scale method. As a result, the permitted tomographic objective angles were from −1.7° to 2.5°, a range of 4.2° for all 4 anatomical structures. When this result was compared with a previous geometric result, the permitted range of the angles was quite narrow. The tomographic objective angles should be manually set in accordance with an optimal tomographic plane for individual patients by using the positioning technique in linear tomography.
A non‐parametric classification rule for several multivariate populations
Authors: Kanazawa Mitsuyo 
Published: June 2006

AbstractIn a classification problem such that a set of observations is classified into a population when it is known beforehand that the observations have come from one of k (>2) multivariate populations, a non‐parametric classification rule based on the Wilcoxon type statistic is proposed, and its consistency is shown. It is also shown that the statistic is asymptotically distributed according to the chi‐square distribution with p degrees of freedom when the observations are classified correctly.
A note on characterization of some laws by the symmetrical distribution of one linear function given another
Authors: Khatri C.G. 
Published: June 2006

AbstractResults corresponding to the symmetrical distribution of a linear vector function of vector variables given another linear vector function of vector variables are obtained by reducing the problem to one of identical distribution of two linear functions. To have normality for each vector variable, one requires stronger conditions on the coefficients of the linear functions than those required in the Darmois‐Skitovich theorem. It is pointed out that Heyde's result (1970) on the symmetrical distribution of a linear function given another linear function, using the same conditions on the coefficients as those of the Darmois‐Skitovich theorem, is not true. For some cases, there do exist some non‐normal random variables among the components of the linear functions.
Efficiency considerations in the analysis of a competing‐risk problem
Authors: Matthews David E. 
Published: June 2006

AbstractIn many survival studies involving more than one failure mode the data collected include the failure times as well as the failure types. An analysis of these data for evidence of a treatment effect based on a logistic probability model for failure type sacrifices precision for simplicity. ignoring the information contained in the failure times. Alternatively, a competing‐risk analysis using a cause‐specific hazard model may make more efficient use of the available information, but involves additional assumptions and the possibility that the model selected may not be entirely correct. Aspects of this tradeoff between efficiency and simplicity are considered in the context of a two‐sample competing‐risk problem involving proportional hazards for the incidence of failure attributable to each of two different causes.
Sur un test d'égalité des autocovariances de deux séries chronologiques
Authors: Melard Guy , Roy Roch 
Published: June 2006

AbstractWe propose a test for the equality of the autocovariance functions of two independent and stationary time series. The test statistic is a quadratic form in the vector of differences of the first J + 1 autocovariances. Its asymptotic distribution is derived under the null hypothesis, and the finite‐sample properties of the test, namely the bias and the power, are investigated by Monte Carlo methods. A by‐product of this study is a new estimator of the covariance between two sample autocovariances which provides a positive definite covariance matrix. We establish the convergence of this estimator in the L1 norm.
Asymptotic expansions for the distributions of statistics based on a correlation matrix
Authors: Konishi Sadanori 
Published: June 2006

AbstractAn asymptotic expansion is given for the distribution of the α‐th largest latent root of a correlation matrix, when the observations are from a multivariate normal distribution. An asymptotic expansion for the distribution of a test statistic based on a correlation matrix, which is useful in dimensionality reduction in principal component analysis, is also given. These expansions hold when the corresponding latent root of the population correlation matrix is simple. The approach here is based on a perturbation method.
The automatic percentile method: Accurate confidence limits in parametric models
Authors: Diciccio Thomas J. , Romano Joseph P. 
Published: June 2006

AbstractThe problem of constructing confidence limits for a scalar parameter is considered. Under weak conditions, Efron's accelerated bias‐corrected bootstrap confidence limits are correct to second order in parametric familles. In this article, a new method, called the automatic percentile method, for setting approximate confidence limits is proposed as an attempt to alleviate two problems inherent in Efron's method. The accelerated bias‐corrected method is not fully automatic, since it requires the calculation of an analytical adjustment; furthermore, it is typically not exact, though for many situations, particularly scalar‐parameter familles, exact answers are available. In broader generality, the proposed method is exact when exact answers exist, and it is second‐order accurate otherwise. The automatic percentile method is automatic, and for scalar parameter models it can be iterated to achieve higher accuracy, with the number of computations being linear in the number of iterations. However, when nuisance parameters are present, only second‐order accuracy seems obtainable.
Consistent directions for least‐squares estimates
Authors: Massam Hélène 
Published: June 2006

AbstractThe least‐squares estimate θn = Xn+yn of the parameter θ in the linear model Yn = Xnθ + ϵn may not be consistent, but there may be directions u such that u'θn tends to u'θ in some sense. This set of directions u has been characterized in two different papers: Drygas (1976) and Wu (1980). The conditions for consistency appear to be different in the two papers. The purpose of this note is to show that the two conditions are equivalent and that they both show that the consistent directions depend upon the geometry of the row vectors vi, i = 1,…, n, of Xn with respect to the direction u.
Estimators of location based on Kolmogorov‐Smirnov‐type statistics
Authors: Boulanger Alain , Eeden Constance Van 
Published: June 2006

AbstractTwo classes of estimators of a location parameter ø0 are proposed, based on a nonnegative functional H1* of the pair (D1øN, GøN), where

and where FN is the sample distribution function. The estimators of the first class are defined as a value of ø minimizing H1*; the estimators of the second class are linearized versions of those of the first. The asymptotic distribution of the estimators is derived, and it is shown that the Kolmogorov‐Smirnov statistic, the signed linear rank statistics, and the Cramérvon Mises statistics are special cases of such functionals H1*;. These estimators are closely related to the estimators of a shift in the two‐sample case, proposed and studied by Boulanger in B2 (pp. 271–284).
Sur la linéarité asymptotique du premier ordre de statistiques de rang signé
Authors: Tardif Serge 
Published: June 2006

AbstractTwo first‐order uniform asymptotic linearity theorems for signed‐rank statistics are given which generalize similar theorems of Jurečková [Sankhyā Ser. A, 33, 1‐18 (1971)], van Eeden [Ann. Math. Statist., 43, 791‐802 (1972)], and Kraft and van Eeden [Ann. Math. Statist., 43, 42‐57 (1972)]. It is seen that the concordance conditions imposed by these authors are not needed.
Vec and vech operators for matrices, with some uses in jacobians and multivariate statistics
Authors: Henderson Harold V. , Searle S. R. 
Published: June 2006

AbstractThe vec of a matrix X stacks columns of X one under another in a single column; the vech of a square matrix X does the same thing but starting each column at its diagonal element. The Jacobian of a one‐to‐one transformation X → Y is then ∣∣∂(vecX)/∂(vecY) ∣∣ when X and Y each have functionally independent elements; it is ∣∣ ∂(vechX)/∂(vechY) ∣∣ when X and Y are symmetric; and there is a general form for when X and Y are other patterned matrices. Kronecker product properties of vec(ABC) permit easy evaluation of this determinant in many cases. The vec and vech operators are also very convenient in developing results in multivariate statistics.
The uniform convergence of the nadaraya‐watson regression function estimate
Authors: Devroye Luc P. 
Published: June 2006

AbstractIf (X1,Y1), …, (Xn,Yn) is a sequence of independent identically distributed Rd × R‐valued random vectors then Nadaraya (1964) and Watson (1964) proposed to estimate the regression function m(x) = ϵ {Y1|X1 = x{ by

where K is a known density and {hn} is a sequence of positive numbers satisfying certain properties. In this paper a variety of conditions are given for the strong convergence to 0 of essXsup|mn (X)‐m(X)| (here X is independent of the data and distributed as X1). The theorems are valid for all distributions of X1 and for all sequences {hn} satisfying hn → 0 and nh/log n→0.