bluuebunny/crossref_metadata_2025 huggingface dataset:
American Society of Clinical Oncology Recommendations on Fertility Preservation in Cancer Patients
Authors: Lee Stephanie J. , Schover Leslie R. , Partridge Ann H. , Patrizio Pasquale , Wallace W. Hamish , Hagerty Karen , Beck Lindsay N. , Brennan Lawrence V. , Oktay Kutluk
Published: May 2006

Purpose

To develop guidance to practicing oncologists about available fertility preservation methods and related issues in people treated for cancer.

Methods

An expert panel and a writing committee were formed. The questions to be addressed by the guideline were determined, and a systematic review of the literature from 1987 to 2005 was performed, and included a search of online databases and consultation with content experts.

Results

The literature review found many cohort studies, case series, and case reports, but relatively few randomized or definitive trials examining the success and impact of fertility preservation methods in people with cancer. Fertility preservation methods are used infrequently in people with cancer.

Recommendations

As part of education and informed consent before cancer therapy, oncologists should address the possibility of infertility with patients treated during their reproductive years and be prepared to discuss possible fertility preservation options or refer appropriate and interested patients to reproductive specialists. Clinician judgment should be employed in the timing of raising this issue, but discussion at the earliest possible opportunity is encouraged. Sperm and embryo cryopreservation are considered standard practice and are widely available; other available fertility preservation methods should be considered investigational and be performed in centers with the necessary expertise.

Conclusion

Fertility preservation is often possible in people undergoing treatment for cancer. To preserve the full range of options, fertility preservation approaches should be considered as early as possible during treatment planning.
Reduction of Friction in Deep Drawing of Aluminium Alloys by Generating Local Hydrostatic-Pressure Lubrication
Authors: Groche P , Nitzsche G
Published: May 2006

A new technology has been developed to optimize the aluminium sheet forming process concerning forming limits and adhesive wear. In this method, a lubricant is pumped through openings into the forming zone at the local area of highest contact normal stresses. A hydrostatic pressure lubrication built up in this area and resulted in a clear reduction of the local friction forces. In a strip-drawing test a significant reduction of the total drawing force occured. The position of the openings had a major influence, and this is investigated experimentally and with the aid of finite element analysis.
Friction and Wear Phenomena in Cold Metal Forming: An Integrated Approach
Authors: Dubar L , Dubois A , Dubar M
Published: May 2006

For a given industrial forming process, the bulk behaviour laws in the near-contact surface of the tools and pieces are identified. Finite element models of the process are run to identify the mechanical contact conditions. The mechanical, physical, and chemical contact parameters are then reproduced in an upsetting sliding test. This test involves specimens and contactors taken from industrial workpieces and tools. These tests yield the friction coefficient and the surface quality of the specimens and contactor. A series of accurate correlations are shown between numerical results from finite element method (FEM) real process simulations and industrial data. The final goal of the paper is to apply the methodologies to the monitoring of wear.
Measurements of Normal and Frictional Forces in a Rolling Process
Authors: Henningsen P , Arentoft M , Wanheim T
Published: May 2006

To improve the quality of frictional data and to validate the simulations in rolling, a load transducer for measuring normal and frictional stresses in the deformation zone has been developed. The transducer consists of a strain-gauge-equipped insert embedded in the surface of the roll. The length of the insert exceeds the contact length. By analysing the output from the insert, the frictional stress and normal pressure in the contact zone can be determined. The new concept differs from existing pin designs by less disturbance of lubricant film and material flow and limited penetration of material between the transducer and roll. The transducer is tested at laboratory conditions and is expected to be running in industrial conditions in 2004.
Tribo-Characteristics of Stainless Steel Sheets in Iterative Processes of Sheet Metal Forming
Authors: Nakamura T , Tanaka S , Hayakawa K , Sugisawa M , Aoyama K-I , Shibata J-I
Published: May 2006

The present authors have developed a tribo-simulator for the long-term iterative processes of sheet metal forming. A sheet metal blank wrapped around a mandrel with a rubber sheet can be deformed by the steel ball as a tool to make spiral grooves on the metal sheet, and the frictional force, normal pressure, and temperature on the steel ball can be measured. The tribo-simulator could realize a total sliding length of 7.2 m and an iterative number of 40 under the sliding speed of about 300–800 mm/s. Friction coefficients and temperature can be measured during all the iterative processes. Some tribological tests of different sheets of stainless steel lubricated with various kinds of mineral oil with different viscosities and a solid wax film coating-type lubricant were carried out. As a result, the variation in friction coefficient changed significantly depending on the lubricants and sheets used. The friction coefficient and temperature increment increased markedly after certain iterative processes with galling when using lower-viscosity mineral oil and no lubricant. On the other hand, the friction coefficient and the temperature increment showed approximately low constant values without galling when using the highest-viscosity mineral oil and the solid wax lubricant. The friction coefficient and the temperature increment were approximately constant without galling when using medium-viscosity mineral oil with some extreme-pressure additives. Two different sheets of stainless steel SUS 304 (Japan Industrial Standard) showed different tribological characteristics in spite of the fact that they were the same type of austenite stainless steel.
Methods and Devices Used to Measure Friction in Rolling
Authors: Jeswiet J , Arentoft M , Henningsen P
Published: May 2006

Friction at the workpiece-die boundary, in both bulk forming and sheet forming is, arguably, the single most important physical parameter influencing the processing of metals; yet it remains the least understood. Hence there is a need for basic research into metal-die interface mechanisms. To gain a good understanding of the mechanisms at the interface and to be able to verify the friction and tribology models that exist, friction sensors are needed.

Designing sensors to measure frictional stress in metal working has been pursued by many researchers. This paper surveys methods that have been used to measure friction in rolling in the past and discusses some of the recent sensor designs that can now be used to measure friction both in production situations and for research purposes.
A case study on the application of a genetic algorithm for optimization of engine parameters
Authors: Verma R , Lakshminiarayanan P A
Published: May 2006

Optimization of modern engines is becoming involved because of both the stringent emission norms and the newly found ability to control various parameters in every zone of the map of engines using electronic fuel injection systems, in both steady state and transient conditions. This paper describes a genetic algorithm and its application to engine optimization when a fitness criterion can be described quantitatively. A specific case study on the selection of a simple speed-dependent injection timer for a diesel engine is described. A population of timers is randomly created where the survival depends on the fitness criterion. From the fit and asexual parents that are randomly selected, offspring are produced to replace the least-fit portion of the population belonging to the previous generation. A small percentage of the population is allowed to mutate. The fitness of the population improves every generation and, in the advanced generation, the fittest timer seems to be the most optimum.
Advanced multidimensional spectral analysis and its application for early fault detection
Authors: Oh Jae-Eung , Kim Woo-Taek , Sim Hyoun-Jin , Lee Jung-Yoon
Published: May 2006

For the early detection and diagnosis of a machine fault, it is necessary to identify the source that contains a fault signal, and to estimate the magnitude of the fault signal in the case of multiple input systems. However, most conventional research is based on the fast Fourier transform (FFT) method, so it requires entire time data and cannot be used for fault signals occurring instantaneously. Fourier-based methods are not well suited to the analysis of nonlinear or non-stationary systems owing to their time-varying nature. Thus, in this paper, a wavelet packet based technique that calculates the time-varying coherence functions for input/ output relationships is developed. Advanced multidimensional spectral analysis (MDSA) is introduced, and the proposed method analyses the signal instantaneously in both time and frequency domains. Introducing the instantaneous ordinary coherence function (IOCF), which is obtained from the wavelet packet analysis, it shows the possibility of ‘early fault detection’ by analysing signals instantaneously in time. Thus, by examining the trend of coherence functions, it is possible to find which signal contains the major fault signal and the degree to which the system is damaged.
Crashworthiness characterization and modelling of high-strength steels for automotive applications
Authors: Van Slycken J , Verleysen P , Degrieck J , Bouquerel J , De Cooman B C
Published: May 2006

In recent years significant advances have been made in the field of multiphase steels for automotive applications. Complex steel grades have been developed with exceptional mechanical properties: they combine high strength values with an excellent ductility. Transformation-induced plasticity (TRIP) steels show these properties pre-eminently. The high ductility makes TRIP steels well suited for use in energy-absorbing devices. To guarantee a controlled dissipation of the energy released during a crash, knowledge and understanding of the impact-dynamic material properties are essential. An extensive experimental programme to investigate the strain rate dependent mechanical properties was set up, and the results for two CMnAl TRIP steels and a CMnSi TRIP steel are presented in this paper. A split Hopkinson tensile bar set-up was used for the experiments. Microstructural observation techniques were used to reveal the mechanisms governing the observed high strain rate behaviour. From the results it is clear that the excellent mechanical properties not only are preserved at higher strain rates but even improve. Several phenomenological material models were investigated to describe the strain rate and temperature dependent behaviour of TRIP steels. Both the Johnson—Cook model and an extended version of the Ludwig model were found to give good agreement with the experimental data.
Dynamic characterization and numerical modelling of automotive rubber connections
Authors: Mundo D , Mas P , Clausi D
Published: May 2006

A hybrid numerical—experimental methodology for the dynamic characterization of automotive rubber connections is presented. In order to predict the dynamic response of automotive structures, a finite element (FE) modelling approach is often used. A critical factor in the achievement of accurate dynamic or static predictions is modelling of non-linear connections between closures and car body. An experimental method is proposed for characterizing the dynamic behaviour of automotive weather strips. By means of a dedicated test bed, a frequency-dependent model of complex stiffness is identified for both normal and tangential loading conditions. The stiffness variability with quasi-static deformation amplitude and deformed shape is also investigated. The experimental data are then used to identify a linear FE model of vehicle rubber connections within the range 0—300 Hz. A simplified car door model and frequency response function (FRF) correlations are used to obtain an experimental validation of the proposed modelling approach.
Influence of the nozzle inlet configuration on under-expanded swirling jet
Authors: Lee K-H , Setoguchi T , Matsuo S , Kim H-D
Published: May 2006

The present study addresses experimental results to investigate the effect of nozzle inlet configuration on under-expanded swirling jets, which is generated by a convergent nozzle with four tangential inlets at the supply chamber. Several different types of plugs and needles, which can be regarded as a means to measure the nozzle inlet pressure or temperature, are employed to change the nozzle supply chamber. The jet supply pressure at the tangential inlets is varied to obtain the swirling jets ranging from a moderately under-expanded to a strongly under-expanded flow at the exit of nozzle. The under-expanded swirling jet flows are specified by the impact pressure measurements and visualized using the shadowgraph optical method. The results show that the major features of the under-expanded swirling jet are considerably influenced by the detailed configuration of the nozzle inlet chamber.
A full-span free-wake model using circular-arc vortex elements and incorporating rotor trim analysis
Authors: Xu G H , Newman S J
Published: May 2006

An analytical method incorporating a free-wake analysis with a rotor trim algorithm is developed for predicting rotor wake geometry and blade loading distribution for a helicopter in hover and forward flight. The wake model of this method is based on a multi-filament full-span free wake, using sophisticated circular-arc vortex elements. The blade model is based on the second-order lifting-line theory to improve the calculation of three-dimensional tip effects. A rotor trim method is given, based on the finite-difference approximation of the blade flapping motion and the trim Jacobian matrix. This is subsequently coupled into the free-wake model. In order to demonstrate the capability of the coupled method, comparisons between the calculated results and the available experimental data of the rotor blade flapping motion for a model rotor are presented covering conditions from hover through forward flight. The free-wake geometry and the blade loading distribution at a low advance ratio are calculated for the H-34 helicopter rotor, and the blade loading distribution is compared with both the measured data and calculated results on the basis of the undistorted wake.
Simplified approach for modelling pilot pursuit control behaviour in multi-loop flight control tasks
Authors: Hess R A
Published: May 2006

A control-theoretic procedure for modelling human pilot pursuit control behaviour is presented. The procedure allows for the development of human pilot behavioural models in multi-loop flight control tasks in a simplified framework emphasizing frequency-domain techniques. Beginning with the primary control loops, each control loop is closed using a combination of output-rate feedback and output-error feedback. It is demonstrated that this approach can accommodate any vehicle dynamics that can be stabilized by a human pilot. In addition, the modelling approach identifies vehicle dynamics that approach the limits of human pilot controllability. The well-documented increase in pilot effective time delays that have been shown to accompany vehicle dynamics requiring lead compensation is also replicated by this modelling approach. A method for predicting handling-qualitiy levels that would be assigned to a particular vehicle and task is presented. A visual cue model is included, which can approximate the effects of degraded visual cues. It is shown that this model can be used to reproduce the three most important measurable effects of visual cue quality upon human operator dynamics, namely, an increase in ‘effective’ pilot time delay, a decrease in crossover frequency, and an increase in error-injected remnant. The ability of the modelling procedure to accommodate different levels of pilot aggressiveness in completing manoeuvres is demonstrated. Finally, an application to a multi-axis rotorcraft flight control problem is presented.
Non-linear unsteady aerodynamic model for insect-like flapping wings in the hover. Part 1: Methodology and analysis
Authors: Ansari S A , Żbikowski R , Knowles K
Published: May 2006

The essence of this two-part paper is the analytical, aerodynamic modelling of insect-like flapping wings in the hover for microair vehicle applications. A key feature of such flapping-wing flows is their unsteadiness and the formation of a leading-edge vortex in addition to the conventional wake shed from the trailing edge. What ensues is a complex interaction between the shed wakes which, in part, determines the forces and moments on the wing. In an attempt to describe such a flow, two-novel coupled, non-linear, wake-integral equations are developed in this first part of the paper, and these form the foundation upon which the rest of the work stands. The circulation-based model thus developed is unsteady and inviscid in nature and essentially two-dimensional. It is converted to a ‘quasi-three-dimensional’ model using a blade-element-type method, but with radial chords. The main results from the model are force and moment data for the flapping wing and are derived as part of this article using the method of impulses. These forces and moments have been decomposed into constituent elements. The governing equations developed in the study are exact, but do not have a closed analytic form. Therefore, solutions are found by numerical methods. These are described in the second part of this paper.
‘Inlet suction’, a load support mechanism in non-convergent, pocketed, hydrodynamic bearings
Authors: Olver A. V. , Fowell M. T. , Spikes H. A. , Pegg I. G.
Published: May 2006

It is shown that a simple parallel pad bearing containing a closed pocket can support load if it operates in an ambient pressure that is appreciably in excess of the cavitation pressure of the lubricating fluid. This arises due to fluid flow driven by subambient pressures in the inlet region of the pad (‘inlet suction’).

Maximum load capacity occurs when the pocket is located near the inlet to the bearing and under conditions such that cavitation is just provoked.
Non-Newtonian effects on elastohydrodynamic behaviour of rotary lip seals
Authors: Hajjam M , Dominique B
Published: May 2006

This study analyses the influence of the non-Newtonian behaviour on the elastohydrodynamic characteristics of lip seals. The thickness variation, the power loss by friction, and the leakage of pumping are analysed, utilizing the Gecim law. More precisely, it is observed that a small viscosity reduction in the sealed zone can lead to a significant dissipation decrease and consequently to a moderate rise in the torque rubbing of the lip, contributing to the increase of its lifespan.
Computational Fluid Dynamics Modelling of Residual Fuel Oil Combustion in the Context of Marine Diesel Engines
Authors: Goldsworthy L
Published: May 2006

A simplified model is presented for vaporization and combustion of heavy residual based fuel oil in high-pressure sprays, in the context of marine diesel engines. The fuel is considered as a mix of residual base and cutter stock. The model accounts for multiple fuel components as well as limited diffusion rates and thermal decomposition rates within droplets by the use of straight-line relationships for the saturation pressure of combustible fuel vapour at the droplet surface as functions of droplet temperature. The energy required for decomposition of heavy molecules is accounted for. Combustion is modelled using a timescale that is the sum of a kinetic timescale based on a single-step reaction and a turbulent timescale based on turbulent mixing rates. The ignition timescale is based on a simple three-equation model. Cellwise ignition is employed. The heavy fuel oil model is applied to two different constant volume chambers that are used to test ignition and combustion quality of marine heavy fuel oil, using the computational fluid dynamics code StarCD version 3.2. Good agreement is shown between trends in measured and computed data including ignition delay, burn rate and spatial distribution of spray and flame parameters. The model is tested for two representative fuels, one with good ignition and combustion properties and one poor. Essentially only two parameters need to be changed to set the fuel quality. These are the ignition delay factor and the activation energy for the high-temperature kinetics. Further tuning of the model to specific fuels is possible by modifying the saturation temperature relationships.
Soot Formation in Diesel Fuel Jets Near the Lift-Off Length
Authors: Pickett L M , Siebers D L
Published: May 2006

Soot formation in the region downstream of the lift-off length of diesel fuel jets was investigated in an optically accessible constant-volume combustion vessel under quiescent-type diesel engine conditions. Planar laser-induced incandescence and line-of-sight laser extinction were used to determine the location of the first soot formation during mixing-controlled combustion. OH chemiluminescence imaging was used to determine the location of high-heat-release reactions relative to the soot-forming region. The primary parameters varied in the experiments were the sooting propensity of the fuel and the amount of fuel-air premixing that occurs upstream of the lift-off length. The fuels considered in order of increasing sooting propensity were: an oxygenated fuel blend (T70), a blend of diesel cetane-number reference fuels (CN80), and a #2 diesel fuel (D2). Fuel-air mixing upstream of the lift-off length was varied by changing ambient gas and injector conditions, which varied either the lift-off length or the air entrainment rate into the fuel jet relative to the fuel injection rate.

Results show that soot formation starts at a finite distance downstream of the lift-off length and that the spatial location of soot formation depends on the fuel type and operating conditions. The distance from the lift-off length to the location of the first soot formation increases as the fuel sooting propensity decreases (i.e. in the order D2 < CN80 < T70). At the baseline operating conditions, the most upstream soot formation occurs at the edges of the jet for D2 and CN80, while for T70 the soot formation is confined to the jet central region. When conditions are varied to produce enhanced fuel-air mixing upstream of the lift-off length in D2 fuel jets, the initial soot formation shifts towards the fuel jet centre and eventually no soot is formed. For all experimental conditions, the observed location of soot formation relative to the heat-release location (lift-off) suggests that soot formation occurs in a mixture of combustion products originating from partially premixed reactions and a diffusion flame. The results also imply that soot precursor formation rates depend strongly on fuel type in the region between the lift-off length and the first soot formation.
Exhaust Tuning of Large-Bore, Multicylinder, Two-Stroke, Natural Gas Engines
Authors: Adair J , Olsen D , Kirkpatrick A
Published: May 2006

In this paper, computational modelling of the exhaust system of two types of large-bore, multicylinder, two-stroke engine is performed. The airflow performance of a four-cylinder V-bank Cooper GMV-4TF engine and a six-cylinder in-line Clark TLA engine is simulated. The simulation includes the computation of pressure wave propagation in the exhaust manifold. Using a modified method of the steepest ascent numerical technique, tuned exhaust manifolds are designed for each engine with the objective of reduced NO emissions. The NO reduction is accomplished by increasing the trapped cylinder mass and correspondingly reducing the peak combustion temperature. The simulations predict NO reductions in the range 10–30 per cent as a result of exhaust tuning.
Investigation of the Early Soot Formation Process in a Transient Spray Flame Via Spectral Measurements of Laser-Induced Emissions
Authors: Aizawa T , Kosaka H
Published: May 2006

In order to investigate the early soot formation process in a diesel spray flame, two-dimensional imaging and spectral measurements of laser-induced emission from soot precursors and soot particles in a transient spray flame achieved in a rapid compression machine (2.8 MPa, 710 K) were conducted. The 3rd harmonic (355 nm) and 4th harmonic (266 nm) Nd: YAG (neodymium-doped yttrium aluminium garnet) laser pulses were used as the light source for laser-induced fluorescence (LIF) from soot precursors and laser-induced incandescence (LII) from soot particles in the spray flame. The two-dimensional imaging covered an area between 30 and 55 mm downstream from the nozzle orifice. The results of two-dimensional imaging showed that strong laser-induced emission excited at 266 nm appears only on the laser incident side of the spray flame, in contrast to an entire cross-sectional distribution of the emission excited at 355 nm, indicating that 266 nm-excited emitters are stronger absorbers and more abundant than 355 nm-excited emitters in the spray flame. The spectral measurements were conducted at three different positions, 35, 45, and 55 mm downstream from the nozzle orifice, along the central axis of the spray, where LIF from soot precursors was observed in a previous two-dimensional imaging study. The spectra measured in upstream positions showed that broad emission peaked at around 400–500 nm, which is attributable to LIF from polycyclic aromatic hydrocarbons (PAHs). The spectra measured in downstream positions appeared very much like grey-body emission from soot particles.
Application of Fume Pyrolysis to Preparation of Superconductive Films
Authors: Miki Takeshi , Yamada Seiji , Ogawa Takao , Kakuta Noriyoshi , Ueno Akifumi , Suzuki Yasushi , Koyama Kuniyuki , Noguchi Seiichiro , Yamada Mamoru
Published: May 2006

Superconductive films composed of Ba2YCu3O7−x were prepared by a fume pyrolysis technique on a YSZ substrate. Films thus prepared and successively annealed at 1273 K in oxygen atmosphere showed superconductive properties below 90 K and zero resistivity was observed at 80 K with 100 μA of the current.
Spontaneous Separation of Enantiomeric Components in Synthetic Bilayer Membranes
Authors: Yamada Norihiro , Sasaki Tazuko , Murata Hiroko , Kunitake Toyoki
Published: May 2006

Enantiomeric components in bilayer membranes of chiral ammonium amphiphiles which contain the azobenzene unit separate spontaneously from each other, as evidenced by absorption spectral changes and electron microscopic observation of helical superstructures.
A New Mechanistic Channel for Photochemical Electron Transfer of Tris(2,2′-bipyridine)ruthenium(II) with Triethylamine. Possible Participation of a Nonemitting Excited State
Authors: Ishitani Osamu , Ishii Koichiro , Yanagida Shozo , Pac Chyongjin , Ohno Takeshi , Yoshimura Akio
Published: May 2006

Laser-flash photolysis of [Ru(bpy)3]2+ (bpy = 2,2′-bipyridine) and triethylamine in methanol gives [Ru(bpy)3]+ within 100 ns, even though the luminescence of [Ru(bpy)3]2+ is not quenched at all by triethylamine in this solvent. Possible participation of a non-emitting state in the redox reaction is suggested.
Langmuir–Blodgett Films of Polyallylamine Modified with (Perfluoroalkyl)phenyl Groups
Authors: Tamura Masanori , Sekiya Akira
Published: May 2006

(Perfluoroalkyl)phenyl groups were introduced to polyallylamine by thiourea bonds. Langmuir–Blodgett (LB) films of the polymers were successfully prepared. Characterization of the films indicated that structural isomerism of substituted benzene has an effect upon the molecular ordering in the LB film and that the limiting area and critical surface tension of the LB films become smaller in the order, ortho, meta, and para isomers.
Vinylation of Methyl Acetate and Methyl Propionate with Methanol in the Presence of Oxygen on Metal Ion-Exchanged Forms of Fluoro Tetrasilicic Mica
Authors: Wang Fey-long , Ueda Wataru , Morikawa Yutaka , Ikawa Tsuneo
Published: May 2006

Among metal ion-exchanged forms of fluoro tetrasilicic mica (M-TSM’s), Ti(IV)-TSM showed the highest catalytic activity at 350 °C for the vinylation of esters with methanol in the presence of oxygen. The values of selectivity for the vinylation of methyl acetate to methyl acrylate and that of methyl propionate to methyl methacrylate attained 87 and 64%, respectively.
A Novel Generation and Behavior of Alkylfluorocarbenoids from α,α-Chlorofluoroalkyl Sulfoxides
Authors: Uno Hidemitsu , Semba Fumihiko , Tasaka Tadataka , Suzuki Hitomi
Published: May 2006

α,α-Chlorofluoroalkyl sulfoxides undergo nucleophilic desulfinylation with a Grignard reagent to give alkylfluorocarbenoids which collapse into cis-fluoroalkenes in the presence of copper(I) iodide.
Horner-Wittig Reaction of Dimethyl 2,3-O-Isopropylidene-d-glyceroylmethylphosphonate and Its Application to the Formal Synthesis of d-erythro-C18-Sphingosine
Authors: Yamanoi Takashi , Akiyama Takashi , Ishida Eiichi , Abe Hiroyuki , Amemiya Masahide , Inazu Toshiyuki
Published: May 2006

Dimethyl 1,2-O-isopropylidene-d-glyceroylmethylphosphonate was found to react with aldehyde in the presence of cesium carbonate in isopropyl alcohol. Using this reaction the formal synthesis of d-erythro-C18-sphingosine was achieved.
Regioselective Titanium-mediated Ring Openings of 2,3-Epoxy Alcohols with Dialkylamine Hydrohalides
Authors: Gao Lian-xun , Murai Akio
Published: May 2006

Titanium-mediated ring openings of 2,3-epoxy-l-ols at the 3-position have been performed more efficiently with use of dialkylamine hydrohalides as sources of halide nucleophiles.
A New Route to (+)-2,3-(Isopropylidenedioxy)-4-cyclopentenone via the Optically Active Dicyclopentadiene Intermediate
Authors: Takano Seiichi , Inomata Kohei , Ogasawara Kunio
Published: May 2006

Chiral synthesis of the dicyclopentadiene derivative and its stereoselective conversion into (+)-2,3-(isopropylidenedioxy)-4-cyclopentenone, a versatile building block for the synthesis of cyclopentanoid natural products, have been described.
Isolation and Structures of Two New Flavonoids from Lindera umbellata
Authors: Ichino Kazuhiko , Tanaka Hitoshi , Ito Kazuo
Published: May 2006

A new chalcone, neo1inderachalcone, and a new dihydrochalcone, neolinderatin, were isolated from the leaves of Lindera umbellata var. lancea. Their structures were established by spectroscopic and chemical method, and syntheses of these compounds were also performed.
The First “Vanadate Hexamer” Capped by Four Pentamethylcyclopentadienyl-rhodium or -iridium Groups
Authors: Hayashi Yoshihito , Ozawa Yoshiki , Isobe Kiyoshi
Published: May 2006

The organometallic oxide clusters [(MCp*)4V6O19] (M = Rh, Ir; Cp* = C5Me5) were prepared and characterized by elemental analyses, SIMS as well as IR and NMR (1H, 13C, 17O, 51V) spectroscopy. Single crystal X-ray analysis showed that [(RhCp*)4V6O19]·4CH3CN·H2O contains the vanadate hexamer core (V6O19). The rhodium cluster displays site selective oxygen exchange with free water at the bridging oxygen atoms.
Liposomes That Can Be Disintegrated by Photo-Irradiation
Authors: Kusumi Akihiro , Nakahama Seiichi , Yamaguchi Kazuo
Published: May 2006

Photo-labile phosphatidylcholine (PLPC) was synthesized which contains 2-nitrobenzyl esters at the terminals of both alkyl chains. Photolysis of the esters generates carboxylate ions in the hydrophobic region of the PLPC membrane, leading to instant disintegration of PLPC liposomes as observed by the phase contrast microscopy. Upon UV irradiation, entrapped macromolecules (45-kdalton ovalbumin) were released from PLPC liposomes.
Rapid O-Glycosidation of Phenols with Glycosyl Fluoride by Using the Combinational Activator, Cp2HfCl2–AgClO4
Authors: Matsumoto Takashi , Katsuki Miyoko , Suzuki Keisuke
Published: May 2006

A new and efficient method for O-glycosidation of phenols is described. Cp2HfCl2–AgClO4 is a highly effective promoter for the coupling reaction between glycosyl fluoride and phenol in the presence of molecular sieves 4A, which proceeds rapidly at low temperature to give O-aryl glycoside in high yields.
Synthesis and Structure of Completely Spin-coupled Trinuclear Copper(II) Complex, [Cu(dmg)2{Cu(bipy)(CH3OH)}2](NO3)2, Bridged by Bis(dimethylglyoximato)cuprate(II) Dianion
Authors: Luneau Dominique , Oshio Hiroki , Okawa Hisashi , Kida Sigeo
Published: May 2006

A linear trinuclear copper(II) complex [Cu(dmg)2{Cu(bipy)(CH3OH)}2](NO3)2 in which bis(dimethylglyoximato)cuprate(II) dianion [Cu(dmg)2]2− bridges two copper(II) ions through its deprotonated oxime oxygens has been synthesized and structurally characterized. Magnetic studies in the 80–300 K range revealed complete spin-coupling at room temperature (μeff: 1.85 μB/3Cu).
Membrane Reactor Using Microporous Glass-supported Thin Film of Palladium. Application to the Water Gas Shift Reaction
Authors: Kikuchi Eiichi , Uemiya Shigeyuki , Sato Noboru , Inoue Hideo , Ando Hiroshi , Matsuda Takeshi
Published: May 2006

A composite membrane consisting of palladium thin film and a microporous-glass tube was applied to a membrane reactor. In the water gas shift reaction, the membrane reactor gave the conversion level exceeding the equilibrium one for the closed system as a result of the separation of hydrogen produced.
A Novel μ-Carbonato-Bridged Binuclear Nickel(II) Complex with N,N′,N″,N″″-Tetrakis(2-aminoethyl)-1,4,8,11-tetraazacyclotetradecane
Authors: Mikuriya Masahiro , Murase Ichiro , Asato Eiji , Kida Sigeo
Published: May 2006

μ-Carbonato-bridged binuclear nickel(II) complexes with N,N′,N″,N″″-tetrakis(2-aminoethyl)-1,4,8,11-tetraazacyclotetradecane(taec), [Ni2(taec)(CO3)](ClO4)2·H2O has been prepared and characterized by electronic spectra, magnetic susceptibilities (80–300 K), and X-ray structure analysis.
Amino Acids Recovered from Fossil Egg Shells of Dinosaurs
Authors: Shimoyama Akira , Muraoka Shiro , Krampitz Gottfried , Harada Kaoru
Published: May 2006

Amino acids recovered from fossil egg shells of dinosaurs showed two kinds. One is antique and small in amount showing the D/L ratio nearly one. The other is more abundant and seems Recent in origin. The antique ones might be residue of peptides at the shell formation.
Random π-Conjugated Copolymers Constituted of Electron-donating Thiophene Units and Electron-accepting Pyridine Units
Authors: Yamamoto Takakazu , Shimura Masaki , Osakada Kohtaro , Kubota Kenji
Published: May 2006

Dehalogenation copolymerization of 2,5-dibromothiophene and 2,5-dibromopyridine with zero-valent nickel complex gives random copolymers with molecular weight of 5 × 104–5 × 106. They show unique doping-undoping cycles which are accounted for by shift of lone pair electron of pyridine ring to p-doped thiophene ring.
Phosphorescence and Photochemical Properties of Benzophenone Adsorbed on Alkali Cations-Exchanged Zeolite
Authors: Okamoto Seiji , Nishiguchi Hiroyasu , Anpo Masakazu
Published: May 2006

Benzophenone adsorbed on the cation-exchanged ZSM-5 zeolite was found to exist as a protonated form and a hydrogen-bonded form. The exchanged cations had a serious effect on the ratio of those concentrations. Both Benzhydrol and benzpinacol were observed as the major products of the photolysis of the system, their yields strongly depending on the kind of the exchanged cations. The protonated species play a significant role on the photoreactions of benzophenone adsorbed on the zeolite.
Application of the Radioactive Multitracer Technique to a Study of Adsorption of Metal Ions on α-Fe2O3
Authors: Ambe Shizuko , Chen Shao Yong , Ohkubo Yoshitaka , Kobayashi Yoshio , Iwamoto Masako , Ambe Fumitoshi
Published: May 2006

The radioactive multitracer technique was applied to a study of adsorption of metal ions on α-Fe2O3 from aqueous solutions. The pH dependence of the adsorption of the elements, Sc, Ga, As(V), Se(IV), Rb, Sr, Y, Zr, Nb, and Mo(VI), was simultaneously determined using a multitracer solution separated from an Ag target irradiated by a 135 MeV/nucleon 12C beam available from the RIKEN Ring Cyclotron. Characteristic adsorption behavior of each element was determined under strictly identical experimental conditions.
A New Class of S-Bridged Pentanuclear Complexes with a Triple Helical Chirality. Crystal Structure of [{RhIII(aet)3}2(HgIICl2)3] (aet = 2-aminoethanethiolate)
Authors: Okamoto Ken-ichi , Konno Takumi , Kageyama Yuichi , Hidaka Jinsai
Published: May 2006

The reactions of fac(S)-[Rh(aet)3] (aet = 2-aminoethanethiolate) with HgX2 (X = Cl or NO3) gave twisted-ellipsoid-type S-bridged pentanuclear complexes with a triple helical chirality, in which two Δ- or Λ-fac(S)-[Rh(aet)3] subunits are linked by three mercury atoms. The crystal structure of [{Rh(aet)3}2(HgCl2)3] was determined by X-ray crystallography.
Formation of (η5-Pentamethylcyclopentadienyl)(1-phenylmethanimine-N,1-dithiolato)cobalt(III) Having a Novel Metallacycle, 1,2,5,3-Cobaltadithiazole, in Reactions of [Co(cp*)(CO)2] with Heterocyclic Compounds Containing S and N
Authors: Kato Akihiro , Tono Masaki , Hisamatsu Naoki , Nozawa Sho-hei , Sugiyama Toru , Kajitani Masatsugu , Akiyama Takeo , Sugimori Akira
Published: May 2006

(η5-Pentamethylcyclopentadienyl)(1-phenylmethanimine-N,1-dithiolato)cobalt (III) (1) containing 1,2,5,3-cobaltadithiazole ring (a novel metallacycle) is formed in the reactions of [Co(cp*)(CO)2] with several precursors of benzonitrile sulfide, 5-phenyl-1,3,4-oxathiazol-2-one (thermal precursor), 4-phenyl-1,3,2-oxathiazolylium-5-olate, and 5-phenyl-1,2,3,4-thiatriazole (photochemical precursors). Compound 1 is also formed in the thermal reactions of [Co(cp*)(CO)2] with 3,6-diphenyl-1,4,2,5-dithiadiazine, 3,5-diphenyl-1,4,2,6-dithiadiazine, 2-diethyl-amino-5-phenyl-1,3,4-dithiazolium perchlorate, 5-phenyl-1,2,4-dithiazol-3-one, or 5-phenyl-1,2,4-dithiazole-3-thione.
Remarkable Effect of Na2CO3 Addition on Photodecomposition of Liquid Water into H2 and O2 from Suspension of Semiconductor Powder Loaded with Various Metals
Authors: Sayama Kazuhiro , Arakawa Hironori
Published: May 2006

An addition of Na2CO3 played the excellent role for the stoichiometric photodecomposition of liquid water over TiO2 and SrTiO3 loaded with various metals such as Pt, RuO2, and NiOX. The addition of Na2CO3 for TiO2 catalysts was more effective than that for SrTiO3 catalysts. It was suggested that the stoichiometric photodecomposition of water was associated with CO32− ion and neither with Na+ nor pH.
Oxidation of Aliphatic and Aromatic Amines with Hydrogen Peroxide Catalyzed by Peroxoheteropoly Oxometalates
Authors: Sakaue Shigeki , Sakata Yasuyuki , Nishiyama Yutaka , Ishii Yasutaka
Published: May 2006

Peroxotungstophosphate (PCWP) was found to be an efficient catalyst for the oxidation of amines with 35% H2O2 under the biphasic or homogeneous condition. Thus, primary and secondary amines were oxidized to oximes and nitrones, respectively, in good yields. Aromatic amines afforded to the corresponding nitroso compounds and/or nitrobenzenes.
Synthesis and Characterization of Trinuclear Metal Complex Showing Helical Chirality
Authors: Kawamoto Tatsuya , Kushi Yoshihiko
Published: May 2006

The reaction of 2-(ferrocenyl)benzothiazoline and palladium(II) acetate forms a trinuclear complex which reveals a monohelical arrangement. The X-ray crystal structure of such monohelical metal complex is reported, together with 1H NMR investigations and the electrochemical properties.
Anion-Sensing Electrodes Based on Nickel(II) Mixed Ligand Complexes
Authors: Sato Noriko , Fukuda Yutaka
Published: May 2006

We have prepared hydrogenphosphate ion-sensing electrodes containing Ni(II) mixed ligand complexes, [Ni(dike)(diam)]X where dike = β-diketonate, diam = N,N′-polyalkylated ethylenediamine, and X = ClO4− or B(C6H5)4− which are non-coordinating anions. In the case of electrodes containing perchlorate complexes as a sensing material, an electrochemical response to hydrogenphosphate ions has been observed, but not in the case of the tetraphenylborate complexes.
Adsorption of Water Vapor on Crystalline Phases of V-P-O
Authors: Takita Yusaku , Sakai Tomoya , Mizuhara Yukako , Ishihara Tatsumi
Published: May 2006

Adsorption of water vapor on crystalline compounds of V-P-O was examined by a TPD method. Water molecules chemisorbed on the V-P-O compounds composed of V(IV) ions such as α- and β-(VO)2P2O7 and VO(PO3)2, were desorbed at 400 °C. However, from compounds consisting of V(V) like V2O5 and VOPO4, only physically adsorbed water molecules were desorbed at 80–200 °C. It can be concluded that the valence of V ions is a key factor for the chemisorption of water vapor on V-P-O compounds.
The Oxidation of Alkoxytributylstannanes with Copper(II) Bromide
Authors: Yamaguchi Jun-ichi , Takeda Takeshi
Published: May 2006

The oxidation of alkoxytributylstannanes with copper(II) bromide in the presence of lithium bromide and t-butoxytributylstannane gave the corresponding carbonyl compounds in good yields under mild reaction conditions.
Highly Diastereoselective Addition of Methyllithium to Chiral α,β-Dialkoxy Ketones and Its Application to the Stereocontrolled Asymmetric Synthesis of Highly Substituted Tetrahydrofurans
Authors: Chikashita Hidenori , Nakamura Yusuke , Uemura Hiromitsu , Itoh Kazuyoshi
Published: May 2006

The nucleophilic addition of methyllithium to chiral α,β-dialkoxy 1,3-dithian-2-yl ketones in ether gave the corresponding Cram type of anti isomers in excellent diastereoselectivity. The method was applied to the stereocontrolled synthesis of optically active and highly substituted tetrahydrofurans.
A Facile Chiral Approach to the Dendrobine Skeleton by Intramolecular Pauson-Khand Reaction
Authors: Takano Seiichi , Inomata Kohei , Ogasawara Kunio
Published: May 2006

A possible chiral synthetic route to the alkaloid (−)-dendrobine has been explored by employing intramolecular Pauson-Khand reaction as the key step. The cobalt complex generated from (S)-carvone yielded a single stereoisomer (10) on intramolecular Pauson-Khand reaction.The adduct 10 was transformed into decarboxy-7,9-dihydrodendrobine by a four-step reaction.
A Chain Compound Built Up by Alternated Arrangement of Molybdenum(II) Trifluoroacetate Dimer and 9,10-Anthraquinone
Authors: Handa Makoto , Sono Hiroaki , Kasamatsu Kenichi , Kasuga Kuninobu , Mikuriya Masahiro , Ikenoue Shuichi
Published: May 2006

Reaction of molybdenum(II) trifluoroacetate, Mo2(O2CCF3)4 and 9,10-anthraquinone (AQ) gave a chain complex, [Mo2(O2CCF3)4·AQ]n. The complex has been characterized by X-ray structural analysis, IR, ESR, and reflectance spectra.
Pd(0) Catalyzed Hydrostannation of Conjugated Dienes. A Facile and Highly Regio- and Stereoselective Synthesis of (Z)-2-Alkenylstannanes
Authors: Miyake Hideyoshi , Yamamura Kimiaki
Published: May 2006

Tetrakis(triphenylphosphine)palladium(0) catalyzes the hydrostannation of conjugated dienes. The reaction proceeds highly regio- and stereoselectively to give (Z)-2-alkenyltributylstannanes. This method is convenient for the stereoselective synthesis of allyltin compounds.
A Novel Binuclear Ruthenium(III) Compound Triply Bridged by Chloride and Disulfide Ligands, [RuCl{P(OMe)3}2(μ-Cl)2(μ-S2)RuCl{P(OMe)3}2]
Authors: Matsumoto Takaya , Matsumoto Kazuko
Published: May 2006

A diruthenium compound with a novel Ru2(S2)Cl2 core has been synthesized. The X-ray crystal study shows that the disulfide ligand bridges the ruthenium atoms in a cis manner with the S-S distance of 1.971(4) Å. The compound has a redox potential of −0.57 V (vs. Ag+/Ag) and a characteristic absorption band at 737 nm.
Intramolecular Hydrogen Atom Transfer in a 2-Methylbenzoyloxyl Radical Revealed by Transient Absorption Kinetics
Authors: Wang Jun , Tsuchiya Masahiro , Tateno Toshiyuki , Sakuragi Hirochika , Tokumaru Katsumi
Published: May 2006

Transient absorption spectroscopy of laser excitation of bis(2-methylbenzoyl) peroxide has revealed that the resulting 2-methylbenzoyloxyl radical undergoes intramolecular hydrogen atom transfer from the neighboring 2-methyl group to give a 2-carboxybenzyl radical with a rate const of 107 s−1 at room temperature in acetonitrile with an activation energy of 4 kcal mol−1 and a frequency factor of 1010.5 s−1.
Preparation and Properties of Highly Electron-accepting Poly(pyrimidine-2,5-diyl)
Authors: Kanbara Takaki , Kushida Takashi , Saito Nobuo , Kuwajima Isao , Kubota Kenji , Yamamoto Takakazu
Published: May 2006

Reaction of 2,5-dibromopyrimidine with a zero-valent nickel complex affords poly(pyrimidine-2,5-diyl). This new polymer is easily converted into electrical conducting materials by chemical and electrochemical reductions, the latter reduction occurring at the highest potential (−1.75 V vs. Ag/Ag+) among reported π-conjugated polymers.
Synthesis of 2′(3′)-O-(L-Phenylalanyl) and 2′(3′)-O-(D-Phenylalanyl) Cytidylyl(3′-5′)adenosine
Authors: Ueno Yoshihito , Mishima Tamako , Hotoda Hitoshi , Hata Tsujiaki
Published: May 2006

A general route to the synthesis of the 2′(3′)-O-aminoacyl CpA using the 1-ethoxyethyl group for tentative protection of the 2′-hydroxyl group of adenosine, is described.
An Efficient Method for the Preparation of Carboxylic Esters via Mixed Anhydrides by the Promotion of a Catalytic Amount of Lewis Acid
Authors: Mukaiyama Teruaki , Shiina Isamu , Miyashita Mitsutomo
Published: May 2006

Various carboxylic esters are prepared in excellent yields by the reaction of nearly equimolar amounts of silyl derivatives of carboxylic acids and alcohols with p-trifluoromethylbenzoic anhydride in the presence of a catalytic amount of Lewis acid.
Catalytic Reduction of Carbon Dioxide on Zn-loaded HZSM-5 Accompanying Aromatization of Propane
Authors: Hattori Tadashi , Yamauchi Syoichi , Satsuma Atsushi , Murakami Yuichi
Published: May 2006

CO2 was successfully reduced on a Zn/HZSM-5 catalyst accompanying the conversion of C3H8 into more valuable products. Further, CO2 was found to suppress the formation of lower alkanes and the deposition of coke.
Discrimination of Reaction Pathways by a Simple Organoaluminum Compound, Me2AlCl, in Lewis Acid Promoted Reactions of Aldehydes with Organosilicon Reagents
Authors: Mori Atsunori , Ohno Hiroshi , Inoue Shohei
Published: May 2006

A novel character of a simple organoaluminum compound, dimethylaluminum chloride, concerning molecular recognition is demonstrated by the crossover reaction of aliphatic and aromatic aldehydes (benzaldehyde and cyclohexanecarbaldehyde) with organosilicon reagents, ketene trimethylsilylacetal and cyanotrimethylsilane in the presence of dimethylaluminum chloride (20–50 mol%) to afford the corresponding aldol adduct of benzaldehyde and cyanohydrin of cyclohexanecarbaldehyde exclusively.
Synthesis and Conductivity of Germanium- or Silicon-Containing Polymers
Authors: Hayashi Teruyuki , Uchimaru Yuko , Reddy N Prabhakar , Tanaka Masato
Published: May 2006

Poly[{(E)-1,1,2,2-tetramethyldigermanylene}ethenylene], poly[(1,1,2,2-tetramethyldigermanylene)-2,5-thienylene], poly[(1,2-dimethyl-1,2-diphenyldigermanylene)-p-phenylene], and poly(methylphenylgermylene) were synthesized. SbF5 doping of above polymers showed the conductivities of the order of 10−4 S/cm, which were similar to, or a little higher than, those of corresponding silicon analogues.
Binuclear Silver (I) Complex with Double Armed Diaza-Crown Ether Containing Short Metal-Metal Separation
Authors: Hirotsu Ken , Miyahara Ikuko , Higuchi Taiichi , Toda Mitsuo , Tsukube Hiroshi , Matsumoto Kiyoshi
Published: May 2006

Binuclear silver (I) complexes of double armed diaza-crown ethers, 7,16-bis(2′-thiazoyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane and 7,13-bis(2′-thiazoyl)-1,4,10-trioxa-7,13-diazacyclopentadecane were prepared. In these complexes, two Ag+ cations were cooperatively coordinated by thiazole-functionalized side arm and parent diaza-crown ring, and their Ag···Ag′ separations (2.790 and 2.969 Å) were either shorter (≈0.1 Å) or slightly longer (≈0.08 Å) than the intermetallic distance (2.889 Å), respectively.