bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of stroke and glide in a foot-propelled avian diver
Authors: Watanuki Yutaka , Takahashi Akinori , Daunt Francis , Wanless Sarah , Harris Mike , Sato Katsufumi , Naito Yasuhiko
Published: June 2005

Bottom-feeding, breath-hold divers would be expected to minimize transit time between the surface and foraging depth, thus maximizing the opportunities for prey capture during the bottom phase of the dive. To achieve this they can potentially adjust a variety of dive parameters, including dive angle and swim speed. However, because of predictable changes in buoyancy with depth,individuals would also be expected to adjust dive behavior according to dive depth. To test these predictions we deployed miniature, dorsally attached data-loggers that recorded surge and heave accelerations at 64 Hz to obtain the first detailed measurements of a foot-propelled diving bird, the European shag Phalacrocorax aristotelis, in the wild. The results were used to investigate biomechanical changes during the descent, ascent and bottom phases for dives varying between 7 m and 43 m deep. Shags descended and ascended almost vertically (60–90° relative to the sea surface). During descent, swim speed varied between 1.2–1.8 m s–1 and the frequency of the foot stroke used for propulsion decreased significantly with depth, mainly due to a fivefold increase in the duration of the glide between strokes. Birds appeared to maintain the duration and the maximum strength of power stroke and thus optimize muscle contraction efficiency.
Effect of an increase in gravity on the power output and the rebound of the body in human running
Authors: Cavagna G. A. , Heglund N. C. , Willems P. A.
Published: June 2005

The effect of an increase in gravity on the mechanics of running has been studied by using a force platform fixed to the floor of an aircraft undergoing flight profiles, resulting in a simulated gravity of 1.3 g. The power spent to maintain the motion of the centre of mass of the body is ∼1.3 times greater than on Earth, due to a similar increase of both the power spent against gravity and to sustain the forward speed changes. This indicates that the average vertical displacement per unit distance and the average direction of the push are unchanged. The increase in power is mainly due to an increase in step frequency rather than to an increase in the work done at each step. The increase in step frequency in turn is mainly due to a decreased duration of the effective aerial phase (when the vertical force is less than body weight), rather than an increase in the stiffness of the bouncing system. The maximal speed where step frequency can match the resonant frequency of the bouncing system is increased by ∼5 km h–1 at 1.3 g. These results suggest a similar running mechanics at higher gravity, maintained at the expense of greater energy expenditure.
Virtual engineering: Methods and tools
Authors: Bernard A
Published: June 2005

This paper presents an overview of actual approaches in virtual engineering, mainly from the design point of view. The evolution of the market has necessitated the reduction of time-to-market, essentially because the product life cycle is shorter, but also because it is very important to proceed more rapidly from an initial conception to a mass production object. As a result of newly evolved software DOI: environments, knowledge-based systems, and product data management, processes for integrated design and manufacturing for new products have emerged. Owing to this evolution of virtual engineering technologies, it has become possible today to validate parts representative of mass production within a very short time. This paper provides an overview of the actual methods and tools in all the components that affect the speed and efficiency of product development, in particular all the possibilities available to the designer, from the earliest stages of a product's life cycle.
Driver swingweighting: A worthwhile process?
Authors: Harper T E , Roberts J R , Jones R
Published: June 2005

The concept that golf clubs should have a uniform weight distribution means that manufacturers invest significant time and money tailoring the swingweight of their clubs. If golfers are unable to perceive significant changes in swingweight, however, and the effect of swingweight on club performance is small, the current manufacturing tolerances on swingweight can be widened, allowing time and cost savings in the assembly process. Testing was conducted using 30 skilled golfers each performing ten tee-shots with four differently weighted drivers. Clubhead mass was varied using screwed inserts of different known masses and the effects on impact location and clubhead speed were both measured. Changes to golf club weight distribution, measured using the swingweight concept, were found to have little effect on player performance and, in general, golfers were unable to perceive small changes in club swingweight. Manufacturing tolerances for component masses appear to offer sufficient control over golf club weight distribution, suggesting that mass balancing procedures may be relaxed during club assembly to provide production time and cost savings.
Machine-learning techniques and their applications in manufacturing
Authors: Pham D T , Afify A A
Published: June 2005

Machine learning is concerned with enabling computer programs automatically to improve their performance at some tasks through experience. Manufacturing is an area where the application of machine learning can be very fruitful. However, little has been published about the use of machine-learning techniques in the manufacturing domain. This paper evaluates several machine-learning techniques and examines applications in which they have been successfully deployed. Special attention is given to inductive learning, which is among the most mature of the machine-learning approaches currently available. Current trends and recent developments in machine-learning research are also discussed. The paper concludes with a summary of some of the key research issues in machine learning.
Surface improvement through hybridization of electrochemical turning and roller burnishing based on the Taguchi technique
Authors: Ebeid S J , Ei-Taweel T A
Published: June 2005

The present work investigates the feasibility of improving surface quality via a novel combined process of electrochemical turning (ECT) with roller burnishing (RB) using the Taguchi fractional factorial experimental design technique. To provide burnishing immediately after the ECT process, non-conductive ZrO2 rollers are attached to the tool electrode during the experiments. The Taguchi technique is employed to identify the effect of ECT working parameters such as applied voltage, electrolyte pressure, workpiece rotational speed, minimum gap, and burnishing force on the output parameters, namely, material removal rate, surface roughness, and the improvement ratio in surface roughness. From the analysis of variance (ANOVA) and signal-to-noise (S/N) ratio response graph, the significant parameters and the optimal combination level of machining parameters are obtained. Experimental results indicate that the combined process effectively improves the surface roughness and eliminates the pitting caused by ECT. Therefore, the combination of ECT and RB is a feasible process by which to obtain a refined finished surface and achieve further surface modifications.
Photochemical Reaction Mechanism of 2,2′-Pyridil in Alcoholic Media
Authors: Yamada Naoki , Hasegawa Miki , Kumagai Ken-ichi , Enomoto Shigendo , Horiuchi Hiroaki , Yoshinaga Tetsutaro , Hiratsuka Hiroshi , Kobayashi Michio , Hoshi Toshihiko
Published: June 2005

Time-resolved transient absorption spectra of photo-irradiated 2,2′-pyridil were measured in PVA films. The broad bands at 552 and ∼455 nm, appearing just after photo-excitation of 2,2′-pyridil, are assigned to the skewed triplet species. The triplet species changes into 1-hydroxy-2-oxo-1,2-di(2-pyridyl)ethyl (pyridoil) radical via the abstraction of a hydrogen atom from the solvent. The radical produced by the photo-irradiation of 2,2′-pyridil is confirmed to be the pyridoil radical from the measurement of the polarized absorption spectrum, with the aid of the stretched polymer film technique and MO calculations. The time-resolved transient absorption spectra of 2,2′-pyridil irradiated by a xenon flash lamp in a 1:1 (v/v) mixed solvent of methanol and ethanol show that the pyridoil radical further abstracts a hydrogen atom from the solvent to afford cis-enediol (cis-1,2-di(2-pyridyl)-1,2-ethenediol) and that cis-enediol is converted into trans-enediol (trans-1,2-di(2-pyridyl)-1,2-ethenediol). 2,2′-Pyridil shows a structured Tn ← T1 absorption spectrum in a 1:1 (v/v) mixed solvent of methylcyclohexane and 2-methylbutane, indicating that 2,2′-pyridil takes a planar structure in the lowest triplet excited state in a nonpolar medium.
Synthesis and Redox Behavior of Dicobalt Complexes Having Flexible and Rigid Linkers
Authors: Shimakoshi Hisashi , Hirose Satoshi , Ohba Masaaki , Shiga Takuya , Okawa Hisashi , Hisaeda Yoshio
Published: June 2005

New dicobalt complexes, [CoII2L], with Schiff-base ligands (L1–L4) having two discrete metal chelating sites, which are connected to each other by flexible and rigid linkers, have been synthesized. The complexes were characterized by IR, UV–vis, and mass spectroscopy as well as elemental analyses. A magnetic study indicates an antiferromagnetic interaction in 4. The redox behavior of the complexes was examined by means of cyclic voltammetry compared with those of the corresponding mononuclear complexes. Redox waves, identified to CoIII/CoII and CoII/CoI, were clearly observed. Electro-generated [CoI2L]2− reacts with alkyl halide at each metal center to give an organocobalt complex.
Preparation of Monometallic Complexes of Non-Macrocyclic Ligands
Authors: Niazi Rahnama Ahmad , Golchoubian Hamid , Pritchard Robin
Published: June 2005

Dicompartmental non-macrocyclic ligands containing six (N4O2) and four (N2O2) coordination atoms were prepared. The ligands were constructed in order to investigate the effect of an opened four-coordination site (non-marcocyclic effect) on the geometrical structure of a complex in a six-coordination site with a labile metal. In this regard, monometallic non-macrocyclic complexes of Zn(II), Co(II), and Co(III) were prepared and characterized. The preparation of a Co(III) complex through two different routes, and also the X-ray crystal structure of a Zn(II) complex demonstrated that the structures of the complexes were intact even in the presence of two bulky phenyl groups in four-coordination site. The characterization of the prepared complexes confirmed the presence of two protons in the four-coordination site of diimine complexes and a lack of them in diamine complexes.
Hybrid Organic–Inorganic Conductor Coupled with BEDT-TTF and Photochromic Nitrosyl Ruthenium Complex
Authors: Okubo Masashi , Enomoto Masaya , Koyama Kazuko , Uwatoko Yoshiya , Kojima Norimichi
Published: June 2005

An organic–inorganic hybrid system coupled with an organic conductor and photosensitive transition metal complex has a possibility to exhibit fascinating multifunctionalities, such as photo-controllable conductor. To explore multifunctional materials, such as a photo-tunable conductor, we prepared (BEDT-TTF)4[RuCl5(NO)]·C6H5CN (BEDT-TTF: 4,5-bis(ethylenedithio)tetrathiafulvalene) by electrocrystallization, and investigated the structural and physical properties. X-ray crystallographic analysis shows alternate layers of BEDT-TTF cations and ruthenium complex anions. The organic layer is formed by the dimers of BEDT-TTF arranged almost perpendicular to each other, which indicates that the donor arrangement of this salt belongs to κ-type. Based on the Raman spectrum, the oxidation state of the BEDT-TTF molecules is estimated to be +0.7. X-ray structural analysis and the EPR spectra suggest that there is a partial electron transfer from BEDT-TTF to the π* orbital of NO ligand in [RuCl5(NO)] through a short intermolecular contact. A magnetic susceptibility measurement and the EPR spectra proved this compound to be a localized spin system due to a strong on-site Coulomb repulsion, which results in the semiconducting behavior of this compound.
Dinuclear Mn(II), Ni(II), and Zn(II) Complexes Bridged by Bis(p-nitrophenyl) Phosphate Ion: Relevance to Bimetallic Phosphodiesterase
Authors: Shiraishi Hitomi , Jikido Reiko , Matsufuji Kanako , Nakanishi Tatsuaki , Shiga Takuya , Ohba Masaaki , Sakai Ken , Kitagawa Hiroshi , Okawa Hisashi
Published: June 2005

2,6-Bis[N,N-di(2-pyridylmethyl)aminomethyl]-4-methylphenol (Hbpmp) has afforded dinuclear Mn(II), Ni(II), and Zn(II) complexes with two bis(p-nitrophenyl) phosphate (BNP−) ions, [M2(bpmp)(bnp)2]ClO4 (M = Mn (1), Ni (2), Zn (3)). The structure of 1·2MeCN has been determined by the single crystal X-ray method. It has a dinuclear core structure bridged by the phenolic oxygen atom of bpmp− and two BNP− ions. Each metal center has a pseudo octahedral geometry with an average Mn-to-donor bond distance of 2.207 Å. Physicochemical properties of 1–3 are studied and their relevance to biological phosphodiesterase is discussed.
cis-trans-cis-Tetrabromotetramethylcyclotetrasiloxane: a Versatile Precursor of Ladder Silsesquioxanes
Authors: Unno Masafumi , Chang Shengho , Matsumoto Hideyuki
Published: June 2005

The title compound was isolated for the first time by a novel procedure including dephenylbromination of cyclotetrasiloxane. The stereostructure of the tetrabromide was confirmed by condensation with diphenylsilanediol, affording anti-tricyclo[7.3.1.13,7]hexasiloxane. This tetrabromide spontaneously decomposed in air to afford a white powder insoluble in organic solvents. Measurements of the TG, IR, and solid-state NMR spectra of the product revealed that a ladder polysilsesquioxane with high thermal stability and stereoregularity was obtained.
The Electronic Effects of Bulky Aryl Substituents on Low Coordinated Phosphorus Atoms in Diphosphenes and Phosphaalkenes by Functionalization at the Para Position
Authors: Kawasaki Subaru , Nakamura Akitake , Toyota Kozo , Yoshifuji Masaaki
Published: June 2005

The electronic effects of bulky aryl substituents on low coordinated phosphorus atom(s) in diphosphenes and phosphaalkenes have been examined by means of functionalization at the para position of the substituents. Bulky bromobenzenes bearing an electron-donating or electron-withdrawing group at the para position were prepared as precursors of the substituents and some of them were applied to preparations of the corresponding diphosphenes and fluorenylidene(phenyl)phosphines bearing low-coordinated phosphorus atom(s). Electronic perturbation by the para-substituent in the system was indicated by UV–vis spectra and 31P NMR chemical shifts. These observations can be attributed to effects induced by electronic properties of the bulky aryl substituent(s) on the lone pair of the low-coordinated phosphorus atom.
Reaction of Ketone Hydrazones with Diselenium Dihalides: Simple Synthesis of Δ3-1,3,4-Selenadiazolines and 2,5-Diarylselenophenes
Authors: Okuma Kentaro , Izaki Toshiharu , Kubo Kento , Shioji Kosei , Yokomori Yoshinobu
Published: June 2005

Sterically congested cis- and trans-Δ3-1,3,4-selenadiazolines were isolated by one-pot reactions of ketone hydrazones with diselenium dibromide, which suggested the in situ formation of selone and diazoalkane intermediates. The thermolysis of these compounds gave symmetrical olefins, whereas oxidation afforded the corresponding azines. The reaction of acetophenone hydrazones with diselenium dibromide afforded 2,5-diarylselenophenes in moderate yields. The reaction proceeded through selone intermediates.
Photoisomerization and Photoinduced Hydrogen-Atom Transfer in 1-Chloro-4-(2-pyrrol-2-ylethenyl)phthalazine
Authors: Akiu Kei , Saijo Masako , Ikegami Masashi , Arai Tatsuo
Published: June 2005

An olefin having a phthalazine ring and a pyrrole ring (2) exhibited a fluorescence spectrum with a large Stokes shift in the cis-isomer. The cis-isomer composition at the photostationary state was considerably high, so as give an isomer ratio at the photostationary state ([cis]/[trans])PSS of 97/3 upon irradiation at 366 nm. These results indicate the occurrence of intramolecular hydrogen-atom transfer in the singlet excited state. The produced tautomer scarcely gave the trans isomer by a reverse hydrogen-atom transfer, and cis-to-trans isomerization was prevented by the existence of intramolecular hydrogen bonding in the cis isomer. Both cis-2 and trans-2 underwent intersystem crossing to give the same triplet excited state with a lifetime of 10 μs in benzene. Based on these results, the photochemical isomerization of 2 in the singlet excited state and in the triplet excited state is discussed.
Metal Cation-Exchanged Montmorillonite-Catalyzed Addition of Organic Disulfides to Alkenes
Authors: Nishimura Takahiro , Yoshinaka Tomoaki , Uemura Sakae
Published: June 2005

The addition of organic disulfides to alkenes, giving vic-bis(alkylthio)alkanes and vic-bis(arylthio)alkanes, proceeds in chlorobenzene in the presence of a catalytic amount of a variety of metal cation-exchanged montmorillonites (abbreviated as Mn+-monts), Al3+, Fe3+, Zr4+, and In3+ being effective as Mn+. The most effective Fe3+-mont can be reused for the addition of diphenyl disulfide to cyclohexene at least 8 times without an appreciable loss of catalytic activity.
Photochromism of Diarylethene Maleimide Derivatives
Authors: Yamaguchi Tadatsugu , Matsuo Masatsugu , Irie Masahiro
Published: June 2005

Diarylmaleimide derivatives having an indole ring, N-cyanomethyl-2-[2-methoxy-1-benzothiophen-3-yl]-3-[2-methyl-1-octadecylindol-3-yl]maleimide or N-cyanomethyl-2-[2-ethoxy-1-benzothiophen-3-yl]-3-[2-methyl-1-octadecylindol-3-yl]maleimide, were synthesized in an attempt to shift the photosensitive wavelength longer such that it becomes longer than 450 nm. The derivatives underwent the photocyclization reaction upon irradiation with 450–550 nm light in hexane solution and the photogenerated closed-ring isomers returned to the initial open-ring isomers upon irradiation with light longer than 600 nm.
Growth of Nanoporous Silica Spherical Particles by the Stöber Method Combined with Supramolecular Templating Approach
Authors: Shimura Naoki , Ogawa Makoto
Published: June 2005

Nanoporous silica spherical particles with narrow particle size distributions (standard deviation: 0.03–0.22) were synthesized by the Stöber method combined with supramolecular templating approach using tetraethoxysilane and cetyltrimethylammonium chloride. The reaction was conducted at 276 K to observe particle growth. Particles formed after the reaction for ca. 0.5 h, as shown by the fact that the solution became turbid. After the reaction for 0.5 h, particles with an average particle size of 440 nm in diameter were collected by filtration. The particles grew until the silica source was completely consumed. This took 50 h under the present reaction condition. The average particle size reached to ca. 1.8 μm at this stage. The calcined particles were porous with the surface areas of 380–1060 m2 g−1 and the pore diameter of 1.6–2.0 nm.
Development of Catalytic Enantioselective Reactions via Palladium Enolates as Key Intermediates
Authors: Sodeoka Mikiko , Hamashima Yoshitaka
Published: June 2005

This article describes the catalytic reactions that involve the generation of chiral palladium enolates and their reaction with various electrophiles. Two methods to generate the chiral enolates were developed using the two types of novel chiral palladium complexes: Pd aqua complexes and binuclear Pd μ-hydroxo complexes. In these processes, aqua or hydroxo ligand on palladium metal plays an important role as a nucleophile to promote the transmetallation or as a Brønsted base to abstract an acidic α-proton of the carbonyl group. Using the chiral Pd enolates as key intermediates, a highly enantioselective, catalytic aldol reaction, a Mannich-type reaction, a Michael reaction, and a fluorination reaction were developed.
Multiphoton Chemical Reactions on Liquid Beam Surfaces
Authors: Kohno Jun-ya , Mafuné Fumitaka , Kondow Tamotsu
Published: June 2005

In this account, we describe the dynamics of reactions induced by multiphoton excitation of solute and solvent molecules in solutions, studied by means of a liquid beam (a continuous liquid flow in a vacuum) combined with mass spectrometry. Unique reaction intermediates and products are found to be produced and ejected into the gas phase by multiphoton excitation of the molecules in the liquid beam. The reaction dynamics were elucidated by observing the reaction intermediates and products ejected into the gas phase. In particular, we refer to reactions via UV multiphoton excitation of solute molecules, such as ketal formation of phenyl ketones and reduction by solvated electrons, and those via IR multiphoton excitation of solvent molecules, such as formation of internally hot and cold molecules/clusters in the gas phase.
Synthesis of Kinetically Stabilized 1-Silanaphthalenes and Their Properties
Authors: Shinohara Akihiro , Takeda Nobuhiro , Sasamori Takahiro , Tokitoh Norihiro
Published: June 2005

The first kinetically stabilized 1-silanaphthalenes bearing a 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl (Tbt) group or a 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl (Bbt) group were synthesized from the corresponding overcrowded bromosilanes by dehydrobromination using LDA (lithium diisopropylamide) in THF at −40 °C, respectively. The structures of 1-silanaphthalenes were confirmed by 1H, 13C, and 29Si NMR, UV–vis, Raman, and high-resolution mass spectroscopic analyses. These results and the NICS calculations indicated high aromaticity of the 1-silanaphthalenes. In spite of such high aromaticity, Tbt-substituted 1-silanaphthalene is thermally unstable and undergoes gradual dimerization in C6D6 solution to give the corresponding [4 + 2] dimer. By contrast, 1-silanaphthalene bearing a Bbt group on the Si atom was thermally stable even on heating in C6D6 at 120 °C. Tbt-substituted 1-silanaphthalene has high reactivity toward addition reactions at both 1,2- and 1,4-positions, giving the corresponding adducts in the reactions with H2O, MeOH, mesitonitrile oxide, benzophenone, and elemental chalcogens. Tbt-substituted 1-silanaphthalene underwent 1,4-addition reaction with CCl4 to give cis- and trans-adducts having a Cl atom on the Si atom and a CCl3 group at the 4-position.
Computational Spectroscopy of a Bichromophoric Molecule, 2-Methyl-1,2,3,4-tetrahydroisoquinoline, in Solutions
Authors: Kanamaru Nobuaki
Published: June 2005

An ab initio calculation of the title molecule was performed to interpret previously observed electronic spectra of the title system. Since the computation concerns the isolated molecule, possible effects of solvent molecules had to be taken into account, especially for such as Rydberg states. The S3 ← S0, S2 ← S0, and S1n ← S0 absorption bands are (re)assigned to the excited states of the Lb, La/CT, and nNσ* (3s) states, respectively. The minor S1a ← S0 absorption observed at the red area of the S1n ← S0 band in acetonitrile is reinterpreted as being a nNπ* (CT) state. Correspondingly, the π, nN, and aN fluorescence spectra are (re)ascribed to the excited states of the Lb, nNσ*, and nNπ* states, respectively. The nNσ* and nNπ* states are found to be restricted to the equatorial and axial conformers, respectively. The exceptionally long progression of the π fluorescence in hexane is interpreted as being due to the closeness of the La and Lb states.
Bright-green Upconversion Emission of Hexagonal LaF3 : Yb3+, Er3+ Nanocrystals
Authors: De Gejihu , Qin Weiping , Zhang Jisen , Zhao Dan , Zhang Jishuang
Published: June 2005

LaF3 : Yb3+, Er3+ nanoparticles were synthesized through a simple hydrothermal method. The nanoparticles were well-crystallized and exhibited hexagonal structure with fine morphology, as indicated by powder X-ray diffraction, electron diffraction, and transmission electron microscopy. The nanocrystals present a bright-green upconversion luminescence under the 978-nm excitation of a laser diode, which provides a promising upconversion phosphor for optoelectronic or biological applications.
Site-selective Coating of Polymer Thin Film Prepared by the Ink-jet Method on the Patterned Fluoroalkylsilane Monolayer Substrate
Authors: Morita Masamichi , Yasutake Shigekazu , Ishizuka Hirotaka , Fukai Jun , Takahara Atsushi
Published: June 2005

The purpose of this study is to establish the fundamental technology of site-selective coating of polymer thin film utilizing wetting contrast of patterned fluoroalkylsilane monolayer/silanol (Si–OH) surfaces. Polystyrene (PS)/xylene solution was coated on the patterned surface with wetting contrast by ink-jet method. The patterned PS ultrathin films were selectively formed on lyophilic Si–OH areas.
A Simple Route for Preparing Radiolarian-like Mesoporous Silica from Water–Diethyl Ether Binary Solvent System
Authors: Lin Haoxiang , Cui Kai , Yao Youwei , Cai Qiang , Feng Qingling , Li Hengde
Published: June 2005

An interesting radiolarian-like silica sphere has been prepared from a water–diethyl ether binary solvent system, which is characterized by SEM, TEM, XRD, and adsorption experiments. The results indicate its particular morphology and hierarchical structure, i.e., hollow interior and a crust wherein two types of mesopores with radial orientation are located. This silica product embodies a novel morphosynthesis involving unstable water–oil interface.
Highly Fluorescent Naphthalimide Derivatives for Two-photon Absorption Materials
Authors: Li Jing , Meng Fanshun , Tian He , Mi Jun , Ji Wei
Published: June 2005

Novel multi-branched naphthalimide derivatives (TPA-NA1, TPA-NA2, and TPA-NA3) were synthesized by the Sonogashira reaction of N-butyl-4-bromo-1,8-naphthalimide with mono-, di-, and tri-ethynylated triphenylamine. The fluorescence increases with the increase of branch number and the quantum yield is as high as 0.87 for TPA-NA3 in toluene. Two-photon absorption cross sections of TPA-NA1, TPA-NA2, and TPA-NA3 were determined to be 0.42 × 10−20 cm4/GW, 1.4 × 10−20 cm4/GW and 1.0 × 10−20 cm4/GW (open aperture Z-scan, 120 fs, 780 nm), respectively.
New Approach for Preparation of Silver–Polystyrene Heterogeneous Nanocomposite by Polyol Process
Authors: Lee Jong-Min , Kim Dae-Wook , Lee Young-Ho , Oh Seong-Geun
Published: June 2005

Silver nanoparticles are homogeneously immobilized onto the polystyrene surface using polyol process for the first time. The formation mechanism of composite materials was discussed briefly. This novel method can be extended to the preparation of other metal–polymer nanocomposites.
A Facile Route to Fabricate Single-crystalline Antimony Nanotube Arrays
Authors: Li Liang , Xiao Yanhe , Yang Youwen , Huang Xiaohu , Li Guanghai , Zhang Lide
Published: June 2005

Single-crystalline antimony nanotube arrays are fabricated in the anodic alumina membranes using the pulsed electrodeposition technique for the first time. The thickness of Au layer sputtered on the anodic alumina membrane and the pulsed electrodeposition technique are two key factors to produce single-crystalline nanotubes.
A Highly Selective Fluorescent Chemosensor for Hg2+ in Aqueous Solution
Authors: Wang Lei , Wong Wai-kwok , Wu Lei , Li Zao-ying
Published: June 2005

A novel selective chemosensor (quinoxaline-bridged Schiff-base macrocycle) for mercury ion has been designed and synthesized, and it exhibited a remarkable selective fluorescent quench toward Hg2+ in the presence of other metal ions in aqueous solution.
Synthesis, Characterization, and Intramolecular Diels–Alder Reaction Tandem Dehydroaromatization of a Diene-diyne
Authors: Liu Shu-Zhi , Tang Guang-Shi , Wang Jing , Li Xue-Hua
Published: June 2005

5-(2-Methylthio-4-methyl-5-pyrimidinyl)-2,4-pentadiynyl sorbate 2 was synthesized and characterized. It had two conjugating systems, which made its 5J and 6J  1H–13C correlating signals be obtained in gHMBC spectra. Intramolecular Diels–Alder reaction tandem dehydroaromatization of diene-diyne 2 under heating and irradiating resulted in formation of benzolactone. The reaction underwent the two steps: thermochemistry and photochemistry. The intermediate was confirmed using C60 as an intermediate catcher. This reaction represents a rare example of intramolecular Diels–Alder reaction tandem dehydroaromatization of diene-diyne under mild conditions without catalyst and oxidant.
Selective Detection of the Solid-state NMR Signals from the Bacteriochlorophyll a Dimers in a Reconstituted Light-harvesting 1 Complex
Authors: Umetsu Mitsuo , Kadota Tomoyuki , Wang Zheng-Yu , Tanaka Yoshikazu , Adschiri Tadafumi , Nozawa Tsunenori
Published: June 2005

High resolution solid-state 13C NMR spectra have been obtained for bacteriochlorophyll (BChl) a in a light-harvesting (LH) 1 complex utilizing a reconstitution method. The LH 1 complexes were reconstituted with 13C-enriched BChl a and the apo-LH1 polypeptide from Rhodospirillum rubrum. Measurement of the 2-dimentional 13C–13C dipole correlation NMR spectra enabled the selective assignment of the 13C resonance from the BChl a molecules in the reconstituted LH1.
Synthesis of Novel Dimeric Steroidal-nucleoside Phosphoramidates
Authors: Ji Sanhao , Xiao Qiang , Ju Yong , Zhao Yufen
Published: June 2005

Some dimeric steroidal conjugated with 3′-azido-3′-deoxythymidine (AZT) as potential membrane-soluble prodrugs of the phosphate forms were synthesized in good yields and the structures were confirmed on the basis of 1H, 13C, and 31P NMR and ESI-MS.
A Novel Photodeposition Method in the Presence of Nitrate Ions for Loading of an Iridium Oxide Cocatalyst for Water Splitting
Authors: Iwase Akihide , Kato Hideki , Kudo Akihiko
Published: June 2005

IrO2 cocatalysts for water splitting were photodeposited from aqueous solution of (NH4)2[IrCl6] or Na3[IrCl6] in the presence of nitrate ions on La-doped NaTaO3 (denoted as NaTaO3:La) photocatalysts, while metallic iridium particles were deposited in the absence of nitrate ions. The IrO2-loaded NaTaO3:La showed the activity for water splitting 2.5 times higher than the nonloaded NaTaO3:La. In contrast, the steady activity was not obtained for the metallic iridium-loaded photocatalyst, because the back reaction quickly proceeded.
The Electroluminescence Spectrum of Chlorophyll a
Authors: Shimatani Kazuhiro , Tajima Hiroyuki , Komino Takeshi , Ikeda Shingo , Matsuda Masaki , Ando Yoriko , Akiyama Hidefumi
Published: June 2005

We fabricated organic-light-emitting diode (OLED) from chlorophyll a, and measured electroluminescence (EL) and photoluminescence (PL) spectra. The EL spectrum exhibits a peak at 700 nm and a shoulder at 750 nm, while the PL spectrum exhibits a peak at 750 nm. The external quantum efficiency of the fabricated OLED linearly increases for the applied voltage above V = 4 V and reaches to 9 × 10−8 at V = 8 V.
Structure of Bis(iodozincio)methane in THF Solution
Authors: Matsubara Seijiro , Oshima Koichiro , Matsuoka Hideki , Matsumoto Kozo , Ishikawa Kazuhiko , Matsubara Eiichiro
Published: June 2005

Bis(iodozincio)methane, which has been shown to be an efficient reagent for organic synthesis, is obtained as THF solution. The structural information about the reagent as THF solution was corrected by small angle neutron scattering and by anomalous X-ray scattering. Those scattering experiments implied that the prepared bis(iodozincio)methane exists without forming any oligomer or aggregate.
Steep Spin-crossover and LIESST Effect of a New Fe(II) Complex with a Tridentate Ligand Derived from 2-Phenyl-4-formylimidazole and N-Methylethylenediamine
Authors: Torigoe Haruna , Hagiwara Hiroaki , Arata Shinobu , Yamada Masahiro , Matsumoto Naohide
Published: June 2005

A novel FeII spin-crossover (SC) complex, [FeII(HL)2](ClO4)2, has been synthesized, where HL denotes tridentate N3 ligand N-methyl[2-[[(2-phenylimidazol-4-yl)methylidene]amino]ethyl]amine). The FeII complex showed a steep SC at T1/2 = 175 K without frozen-in effect and hysteresis. The crystal structures at the high-spin (HS) and low-spin (LS) states were determined. Though there is no intermolecular interaction and no frozen-in effect, LIESST (light-induced excited spin state trapping) and reverse-LIESST effects were observed.
Novel Carbon Molecular Sieve Membranes Derived from Poly(phenylene oxide) and Its Derivatives for Gas Separation
Authors: Yoshimune Miki , Fujiwara Ichiro , Suda Hiroyuki , Haraya Kenji
Published: June 2005

We succeeded in fabricating new carbon molecular sieve (CMS) membranes as hollow fibers using poly(phenylene oxide) (PPO) and its functionalized derivatives (R-PPO). Gas transport properties were measured for He, H2, CO2, O2, and N2. PPO CMS membranes exhibited higher performances than those of polymeric precursors. The highest performance was attained by trimethylsilyl-PPO (TMSPPO) CMS membrane pyrolyzed at 923 K, of which O2 permeability was 125 Barrer and O2/N2 permselectivity was 10.0 at 298 K.
Functional Group Transformations and Stereochemistry of Silicon-functionalized 7-Silabenzonorbornadienes
Authors: Kawachi Atsushi , Okimoto Masahiro , Yamamoto Yohsuke
Published: June 2005

Functional group transformations of 7-silabenzonorbornadiene derivatives have been investigated. The 7-mesityl-7-silanorbornadiene 1 was prepared and converted into the 7-chloro derivative 5. Reductive lithiation of 5 with lithium naphthalenide afforded the silyllithium 6, which reacted with Me3SiCl and MeI. The reactions of 5 with n-BuLi and PhNHLi gave the 7-butyl derivative 9 and the 7-amino derivative 10, respectively. Each stereochemistry during these transformations was determined by X-ray crystallographic analysis.
Low-temperature Synthesis of Crystalline TiO2 Nanorods: Mass Production Assisted by Surfactant
Authors: Yang Songwang , Gao Lian
Published: June 2005

Crystalline and dispersed rutile TiO2 nanorods with diameters of ≈6–8 nm and lengths of 40–100 nm were synthesized via a low-temperature solution process in the presence of nonionic surfactant P123.
A Bromine Adduct of 2,3,6,7,14,15-Hexamethyl-9,10-distibatriptycene. The First Stibonium–Stiborate Zwitterion
Authors: Uchiyama Yosuke , Yamamoto Gaku
Published: June 2005

2,3,6,7,14,15-Hexamethyl-9,10-distibatriptycene (3) reacted with bromine to give an adduct 4 with the composition of 3·2Br2. X-ray structure analysis and 1H NMR studies revealed that the bromine adduct 4 forms an intramolecular salt composed of a tetracoordinate bromostibonium ion moiety, R3SbBr+, and a hexacoordinate tribromostiborate ion moiety, R3SbBr3−, both in the crystalline state and in solution.
Large-scale, Solution-phase Production of Microsized, Single-crystalline, Hexagonal Gold Microplates by Thermal Reduction of HAuCl4 with Oxalic Acid
Authors: Sun Xuping , Dong Shaojun , Wang Erkang
Published: June 2005

Heating an aqueous oxalic acid/HAuCl4 solution results in the formation of microsized, single-crystalline, hexagonal gold microplates on a large scale.
Selective Conversion of Dimethyl Ether to Propylene and Light Olefins over Modified H-ZSM-5
Authors: Zhao Tian-Sheng , Takemoto Tomokazu , Yoneyama Yoshiharu , Tsubaki Noritatsu
Published: June 2005

Light olefins especially propylene was formed selectively with a propylene/ethylene ratio of 10, from direct conversion of dimethyl ether over ZrO2 and H3PO4-modified H-ZSM-5 catalyst at atmospheric pressure. The improved propylene selectivity was due to adjusted acid property and shape-selective microspores of the modified H-ZSM-5.
A Facile and One-pot Synthesis of High Aspect Ratio Anatase Nanorods Based on Aqueous Solution
Authors: Yang Songwang , Gao Lian
Published: June 2005

Single-crystalline anatase nanorods with high aspect ratios have been synthesized through a facile and one-pot method based on an aqueous solution. The synthesized anatase nanorods have pits, crevices, and dislocations on the surfaces besides the steps, kinks, and terraces on the side walls.
Pressure Effect on the Magnetic Phase Transition of Guest-tunable Weak Ferromagnets [Fe{N(CN)2}2(pyrimidine)](guest) (Guest = Ethanol and Pyrimidine)
Authors: Yuza Kenji , Ishida Takayuki , Nogami Takashi
Published: June 2005

The spontaneous magnetization of [Fe{N(CN)2}2(pm)](ethanol) (pm = pyrimidine) was suppressed under pressure up to 0.5 GPa and finally behaved as a paramagnet at 0.6 GPa. The loose packing of the host–guest complex structure seems responsible for the pressure-sensitive magnetism. On the other hand, [Fe{N(CN)2}2(pm)](pm) exhibited relatively small pressure dependence of the phase transition behavior.
Fabrication of 2D Ordered Porous ZnO Films Using 3D Opal Templates by Electrodeposition
Authors: Yan Hongwei , Yang Yingling , Fu Zhengping , Yang Beifang , Wang Zhen , Xia Linsheng , Yu Shijun , Fu Shengquan , Li Fanqing
Published: June 2005

The fabrication of two-dimensionally ordered porous zinc oxide films using three-dimensional colloidal crystal templates by electrodeposition is reported. The hydrophilicity of the substrate and the hydrophobicity of the template are utilized to control the generated structures.
Coupling of ICP-MS and Multitracer Technique as a New Method to Investigate Dynamics of Various Elements in Soil-water System
Authors: Mitsunobu Satoshi , Takahashi Yoshio , Hirunuma Rieko , Haba Hiromitsu , Enomoto Shuichi
Published: June 2005

Coupled application of multitracer method for the sorption experiments and ICP-MS for leaching experiments was proposed as a new method to study the dynamics of various elements in soil–water systems. This method enables us to obtain reversibility and the time required to attain the steady-state simultaneously for various elements in soil–water system. An example of the results obtained by this method was shown for the case of Co in this letter.
Fabrication of Hierarchical Zeolitic Material from Zeolite Nanoprecursors and Macromolecular Template
Authors: Naik Sajo P , Chiang Anthony S T , Sasakura Hideshi , Yamaguchi Yukio , Okubo Tatsuya
Published: June 2005

Hierarchical zeolitic material possessing three generations of micro-, meso-, and macroporosities was fabricated under controlled steaming at 145 °C through a dual-template approach using tetrapropylammonium hydroxide (TPAOH) and poly(methyl methacrylate) (PMMA) latex particles as micropore and macropore templates, respectively.
Micro-patterning of LiMn2O4 Electrode Using Sol–Gel Process for Lithium Micro-batteries
Authors: Dokko Kaoru , Sugaya Jun-ichi , Munakata Hirokazu , Kanamura Kiyoshi
Published: June 2005

Micro-dot array of LiMn2O4 on Au substrate was prepared by sol–gel process combined with a micro-injection technology. The size of a dot of LiMn2O4 was 50 μm, and dot population density on the substrate was 5000 dots cm−2. Electrochemical properties of micro-dots of LiMn2O4 in a PMMA-gel electrolyte were characterized as cathode for lithium micro-batteries. A micro-dot of LiMn2O4 exhibited a discharge capacity of 1.8 μC dot−1, and the capacity fade was only 21% over 200 charge–discharge cycles.
Synthesis of β-MoO3 by Simple Evaporation of Molybdic Acid Solution Containing Nitric Acid
Authors: Mizushima Takanori , Fukushima Kazuya , Huong Tran Mai , Ohkita Hironobu , Kakuta Noriyoshi
Published: June 2005

β-MoO3 was successfully synthesized through a simple evaporation of a molybdic acid solution prepared by a cation exchange of an aqueous solution of Na2MoO4·2H2O. The key was an addition of a small amount of nitric acid before the evaporation. Heating the dried molybdic acid at 573 K in oxygen resulted in a formation of a bright yellow powder, which was confirmed to be β-MoO3 free from α-MoO3 by XRD and Raman spectroscopy.
Experience with radiofrequency closure of varicose veins (VNUS)
Authors: Das S K , Sahoo N , Shanaz M
Published: June 2005

Objective: The aim of this study was to reproduce the results of VNUS closure in our setting; to minimize the cost associated with the procedure; and to reduce the need for an experienced ultrasonographer during the procedure.

Methods: Over a two-year period, 26 patients (42 limbs) were treated. A VNUS radio-frequency machine was used and assisted by intraoperative localization using Sonosite ultrasound, which was operated by the surgeon. All patients were treated under general anaesthetic. Nine patients were operated as a day case and 17 others stayed overnight. Median follow-up period was seven months.

Results: The mean age of the patients was 37 years (range 19–69). Eighteen patients had primary and eight had recurrent varicose veins. Sixteen patients underwent bilateral and 10 underwent the unilateral procedure. Long saphenous vein (LSV) closure was performed in 41 limbs and short saphenous vein closure in two limbs. The LSV was accessed at the ankle in 36 and at knee in three limbs. In two other limbs, groin exploration with retrograde closure of the LSV was achieved. One patient developed numbness at phlebectomy site. None of the patients had deep vein thrombosis and all the treated veins were closed at the one-week scan. In bilateral cases, one catheter was used instead of two for closure in 12 of the 16 limbs. Using our approach, we were able to make a cost savings of £8,600.00.

Conclusion: Technical success in radiofrequency vein closure can be achieved without the need for an additional ultrasonographer. We have shown that our approach is safe, effective and less expensive to deliver.
Sclerotherapy for leg varicose veins
Authors: Corabian P , Harstall C
Published: June 2005

Sclerotherapy has been used since the 1940s as an alternative or adjunct to surgery for all types of leg varicose veins. However, its role in the management of this condition, particularly in relation to other types of treatment, has yet to be determined. There is still no convincing evidence to support or not support its use for symptomatic varicose veins. Sclerotherapy appears to be the treatment of choice in managing reticular varicosities and telangiectasia for relief of pain and/or discomfort and vessel disappearance in the short term. Following surgery, sclerotherapy may achieve good results in varicose veins that have not fully disappeared or recur. Its use as the first treatment option for large varicose veins remains controversial. Currently, the appropriate techniques and sclerosants to be used for various types of leg varicose veins are still debated. Future research is needed to establish uniform and objective diagnostic and patient selection criteria, definitions for treatment failure and vein recurrence, and outcome measures. Further objective evaluation of the efficacy and appropriate use of the numerous sclerotherapy techniques is essential.
The outcome of recurrent varicose vein surgery: the patients' perspective
Authors: Edwards A G , Donaldson O , Bennetts C , Mitchell D C
Published: June 2005

Objectives: This study was performed to assess the patient's perception of the outcome of recurrent varicose vein surgery.

Methods: Patients who underwent surgery for recurrent varicose veins between 1 January 1995 and 31 December 1998 were sent a questionnaire and Aberdeen Varicose Vein Severity Score (AVVSS) in September 2003.

Results: A total of 48 questionnaires were distributed and 40 responses (83%) were received. The mean length of follow-up was 81.78 months. Outcome was 'excellent' (no varicose veins) for four patients, 'satisfactory' for 22 (small, asymptomatic recurrence), 'unsatisfactory' for 10 (symptomatic recurrence) and 'worse' for four patients; 65% thought that the outcome was successful (excellent or satisfactory) and 35% a failure. The median AVVSS in the success group was 11.50 (IQR 7.94–19.69) compared with 29.63 (IQR 18.46–40.31) in the failure group ( P = 0.0009, Wilcoxon).

Conclusions: Two-thirds of patients undergoing surgery for recurrent varicose veins are satisfied with the outcome, nearly seven years after surgery. One-third will regard surgery as having failed. Patients should be advised of these potential outcomes prior to surgery.
Effect of leg elevation on healing, venous velocity and ambulatory venous pressure in venous ulceration
Authors: Dix F P , Reilly B , David M C , Simon D , Dowding E , Ivers L , Bhowmick A , McCollum C N
Published: June 2005

Objective: Current treatment of venous leg ulcers (VLU) includes four-layer bandaging, appropriate superficial venous surgery and leg elevation. The aims of this study were to: investigate a device designed to measure leg elevation; assess how long patients elevate; and to assess the effect of elevation on ulcer healing, femoral vein velocity (FVV) and popliteal vein cross-sectional area (PVCSA), and venous pressure.

Patients and methods: A datalogger and accelerometer were manufactured to measure leg elevation. The device was validated in eight control subjects; elevation was measured in 24 patients with VLU. Ulcers were traced over six weeks in 29 patients and elevation measured to correlate healing with elevation. Ten patients and 10 controls underwent duplex measurement of FVV and PVCSA to measure flow in relation to posture; nine patients underwent measurement of venous pressure with postural changes. Non-parametric statistical analysis was used.

Results: The datalogger accurately recorded all episodes of elevation. Median (range) elevation time was 53 (0–350) mins/24 h; correlation between ulcer healing and elevation was poor at 0.103 ( P=0.616, Spearman); change in posture from sitting to supine produced a significant increase in median (range) FVV from 11 (7–24) to 34 (22–66) in VLU ( P=0.005) and 15 (12–34) to 38 (16–69) in controls ( P=0.005, Wilcoxon). Change in posture from supine to 25 degrees elevation produced no change in FVV in either group ( P=0.173 in VLU, P=0.327 in controls, Wilcoxon). In VLU, sitting PVCSA was 1.07 (0.51–1.45) cm2. Supine position significantly reduced the area to 0.46 (0.27–1.01) cm2 ( P=0.005, Wilcoxon). On elevation to 25°, PVCSA was further reduced to 0.28 (0.07–0.63) cm2 ( P=0.058, Wilcoxon). In controls, sitting PVCSA was 0.79 (0.31–1.56) cm2, supine was reduced to 0.46 (0.27–1.09) cm2 ( P=0.047, Wilcoxon) and on elevation was reduced to 0.23 (0.10–0.44) cm2 ( P=0.005, Wilcoxon). Venous pressure standing was 99 (73–116) mmHg, reduced to 76 (53–113) mmHg on sitting ( P=0.084), and further reduced to 23 (7–36) mmHg supine ( P=0.008, Wilcoxon).

Conclusions: Leg elevation in patients with VLU is poor but can be accurately measured. Elevation in the presence of compression may not improve ulcer healing. Postural changes of the leg can produce an increase in deep venous flow and a reduction in venous pressure.