bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reaction of thio and seleno phosphoric acid derivatives with O‐thioacylated hydroxylamine
Authors: Cholewinski Grzegorz , Witt Dariusz , Majewski Radosław , Ossowski Tadeusz , Rachon Janusz 
Published: November 2007

AbstractThe reactivity of thio and seleno analogs of phosphoric acid 1b–f with O‐thioacylhydroxylamine 2 was examined. The experimental evidence for the proposed mechanism involving an N—O bond cleavage and a single electron transfer process (SET) from phosphate anions was collected. The influence of phosphoric acids 1 structure and their oxidation potentials on the course of the reaction and products 3, 4, 6, 7 distribution was presented. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:767–773, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20368
Effect of borane source on the enantioselectivity in the enantiopure oxazaborolidine‐catalyzed asymmetric borane reduction of ketones
Authors: Wang Xiao , Du Juanjuan , Liu Han , Du Da‐Ming , Xu Jiaxi 
Published: November 2007

AbstractThe effect of borane source on enantioselectivity in the enantiopure oxazaborolidine‐catalyzed asymmetric borane reduction of ketones has been investigated by using (S)‐3,1,2‐oxazaborobicyclo[3.3.0]octane and (S)‐7,3,1,2‐thiaxazaborobicyclo[3.3.0]octane as catalysts. The results indicate that the enantioselective order of different borane sources is borane–dimethyl sulfide < borane–N,N‐diethylaniline < borane–THF for the asymmetric reduction of a ketone under the same conditions. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:740–746, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20370
Peculiar reaction of N2‐acyl derivatives of 2‐aryl‐5‐hydrazino‐1,3‐oxazole‐4‐carbonitriles with the lawesson reagent
Authors: Shablykin Oleg V. , Brovarets Vladimir S. , Rusanov Eduard B. , Drach Boris S. 
Published: November 2007

AbstractEasily accessible N2‐acyl derivatives of 2‐aryl‐5‐hydrazino‐1,3‐oxazole‐4‐carbonitriles react peculiarly with the Lawesson reagent. In addition to thionation, the reaction involves a recyclization to afford new substituted 2‐(5‐amino‐1,3‐thiazol‐4‐yl)‐1,3,4‐thiadiazoles. Their structure is corroborated spectroscopically and by the X‐ray diffraction method. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:782–785, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20413
Effects of liquid viscosity on inception of disturbance waves and droplets in gas–liquid annular two‐phase flow
Authors: Mori Koji , Yoshida Haruyuki , Nakano Kuniaki , Shiomi Yoichi 
Published: November 2007

AbstractThe structure of gas–liquid two‐phase flow is investigated in order to establish a reliable criterion for the development of disturbance waves and droplets considering the effects of liquid viscosity. The structure of the gas–liquid interface and the flow rate of droplets entrained in gas are measured simultaneously at five kinematic viscosities (1.0, 3.2, 9.9, 30, 70 mm2/s). The time‐series traces of liquid film thickness measured by five holdup probes reveal that the inception of disturbance waves occurs at a liquid Reynolds number of 200 or a non‐dimensional liquid film thickness of 6.5. It is also shown that droplets are generated before the inception of disturbance waves with increasing liquid kinematic viscosity at a liquid velocity of 0.02 to 0.03 m/s. As previously published criteria for the inception of droplets are found to be unsatisfactory, a new critical condition for droplet generation balancing the interfacial shear stress $τi$ with the wave height h and surface tension σ is proposed: $τih/σ=0.025$. This relation describes the action of shear force and surface tension on wave crests, and is notably independent of liquid viscosity. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 529–541, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20176
Heat transfer characteristics of a reservoir embedded loop heat pipe (2nd report, Influence of noncondensable gas on heat transfer characteristics)
Authors: Ishikawa Hiroaki , Ogushi Tetsuro , Nomura Takehide , Noda Hiroyuki , Kawasaki Haruo , Yabe Takahiro 
Published: November 2007

AbstractHigh‐powered satellites need larger heat rejection areas. A deployable radiator is one of the key technologies for a high‐powered satellite bus. A Reservoir Embedded Loop Heat Pipe (RELHP) is a two‐phase heat transfer device that constitutes the deployable radiator. RELHP has an evaporator core which is used as a liquid reservoir to enhance operational reliability. For use on satellites, RELHP is required to have a lifetime greater than 10 years. In the case of conventional heat pipes, it is generally known that noncondensable gas (NCG) has worse heat transport characteristics. On the other hand, the influence of NCG on a RELHP is not still obvious. This paper presents the heat transport characteristics of RELHP for the case of changing NCG volume by experiment and calculation. It was found that NCG increases temperature rise at the evaporator. NCG volume in a RELHP has a great influence on heat transport characteristics due to the reservoir pressure increase caused by NCG. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 459–473, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20181
Thermal diffusion analysis for LED module
Authors: Su Ay , Liu Y. C. , Chen C. Y. 
Published: November 2007

AbstractAn experimental investigation of the thermal characteristic of the LED chip and the sensitivity of illumination with thermal substrate is discussed in this study. An optimum thermal diffusion area to the heat flux of LED system is also conducted. Results show that a red LED chip has lower electrical resistance, and therefore has lower power consumption than that of green and blue LED chips. Given these three colors of lighting LEDs, the red LED chip is more sensitive to the thermal environment. A red LED's lighting illumination is decreased almost 12% when the substrate temperature difference is increased to 25°C. Under the same condition, an LED's illumination experiences only a 2 to 2.5% reduction for the green and blue LED chip. Copyright © 2004 Wiley Periodicals, Inc.Thermal diffusion area results show a close correlation between thermal diffusion ratio and LED substrate temperature. If the upper limit LED substrate temperature is set at 50°C and the thermal diffusion ratio approximates 72 cm2/w, for a 500 cm2 thermal diffusion area, it can sustain an optimum heat flux at 7 watts. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 449–458, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20182
Molecular modeling of polymer–clay nanocomposite precursors: Lysine in montmorillonite interlayers
Authors: Davis Alicia M. , Joanis Gary , Tribe Lorena 
Published: November 2007

AbstractThe layered structure of clays with interlayer cations leads to unique chemical and mechanical properties, which have been capitalized on in the field of polymer/layered silicate nanocomposites. Hydrophilic silica surfaces can become organophilic with the inclusion of alkylammonium cations, which improve the wetting characteristics of the polymer matrix. In fact, the molecular level interactions of amino acids, either natural or non‐natural, with clay surfaces are at the heart of fields of study as diverse as nanocomposites fabrication, drug delivery, bio‐remediation of soils and catalysis of biological polymers, to name a few. The ubiquity of these systems and the potential uses to which they could be put suggests the necessity of a deeper understanding of the interplay of bonds, conformations, and configurations between the molecules and the hosts. The interactions of the amino acid lysine with sodium montmorillonite were studied using theoretical molecular modeling methods. The interlayer spacing of montmorillonite was increased by incorporating water molecules and allowing the system to evolve with molecular mechanics. Care was taken to retain the sodium cations in the interlayer. The initial amino acid conformation was obtained surrounding the molecule with numerous discrete water molecules and minimizing the system at the semi empirical level. The optimized amino acid was then placed in the interlayer space in a series of initial positions. Molecular mechanics calculations were performed and the final positions were analyzed. The results tended to indicate the preponderance of configurations which included surface‐sodium‐amino acid complexes with a variety of spatial arrangements. These results were compared with molecular dynamics calculations of similar systems from the literature. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
An improved SCPF scheme for polarization energy calculations
Authors: Mazur Grzegorz 
Published: November 2007

AbstractConvergence of the Self‐Consistent Polarization Field (SCPF) method of polarization energy calculations for organic molecular materials is analysed. Use of the Conjugate Gradients method for solving the SCPF equations is proposed. Efficiency of both the original and the newly proposed approach is compared for selected model systems. Brief discussion of the factors influencing the performance of Krylov‐space‐based methods for polarization energy calculations is presented. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
A flexible implementation of frozen‐density embedding for use in multilevel simulations
Authors: Jacob Christoph R. , Neugebauer Johannes , Visscher Lucas 
Published: November 2007

AbstractA new implementation of frozen‐density embedding (FDE) in the Amsterdam Density Functional (ADF) program package is presented. FDE is based on a subsystem formulation of density‐functional theory (DFT), in which a large system is assembled from an arbitrary number of subsystems, which are coupled by an effective embedding potential. The new implementation allows both an optimization of all subsystems as a linear‐scaling alternative to a conventional DFT treatment, the calculation of one active fragment in the presence of a frozen environment, and intermediate setups, in which individual subsystems are fully optimized, partially optimized, or completely frozen. It is shown how this flexible setup can facilitate the application of FDE in multilevel simulations. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
The El Nino‐Southern Oscillation and winter precipitation extremes over India
Authors: Revadekar J. V. , Kulkarni Ashwini 
Published: November 2007

AbstractDaily rainfall data for the winter season October–December for the long period of 102 years 1901–2002 over southeast peninsular India have been used to study the characteristics of daily precipitation extremes. The frequency and intensity of extreme precipitation events do not show statistically significant long‐term trend. The relationship of El Nino‐southern oscillation index with these extremes shows that this index can be used to predict frequency and intensity of extreme precipitation events, 4–6 months in advance. However spell lengths of continuous wet/dry days are not modulated by variations in Pacific sea surface temperatures. Copyright © 2007 Royal Meteorological Society
Trends in the rainfall pattern over India
Authors: Guhathakurta P. , Rajeevan M. 
Published: November 2007

AbstractNew monthly, seasonal and annual rainfall time series of 36 meteorological subdivisions of India were constructed using the monthly rainfall data for the period 1901–2003 of fixed network of 1476 rain gauge stations. In the new network, on an average, there is one rain gauge station for every 3402 Sq km area. The new rainfall series is temporally as well as spatially homogenous. Linear trend analysis was carried out to examine the long‐term trends in rainfall over different subdivisions and monthly contribution of each of the monsoon months to annual rainfall. During the south‐west monsoon season, three subdivisions viz. Jharkhand, Chattisgarh, Kerala showed significant decreasing trend and eight subdivisions viz. Gangetic WB, West UP, Jammu and Kashmir, Konkan and Goa, Madhya Maharashtra subdivision, Rayalseema, Coastal AP and North Interior Karnataka showed significant increasing trends. It has been found that the contribution of June, July and September rainfall to annual rainfall is decreasing for few subdivisions while contribution of August rainfall is increasing in few other subdivisions. EOF analysis is also done to know the spatial distribution of rainfall. The all India Monthly, seasonal and annual rainfall series constructed based on the 1476 stations are also reported. Copyright © 2007 Royal Meteorological Society
Influences of atmospheric circulation on the variability of wet sulfate deposition
Authors: Dayan Uri , Lamb Dennis 
Published: November 2007

AbstractPrecipitation chemistry data from the National Atmospheric Deposition Program were related to weather data from the Climate Diagnostics Center in order to reveal the influence of large‐scale circulation patterns on the wet deposition of sulfate downwind of the Ohio River Valley, where SO2 emissions were curtailed sharply in the mid‐1990s. The chemistry data from five precipitation‐sampling sites were combined to provide a regional average for each summer season over the 21‐year period from 1984 to 2004. The long‐term trend of sulfate concentration is associated to a statistically significant extent by composited flow patterns associated with the East Pacific–North Pacific index. The regional weather pattern for the sulfate‐rich years is associated with an intensification of the Bermuda High over the southeastern United States at the surface in tandem with a weakening of the 500‐hPa geopotential height (GPH) climatological trough located over the northeastern United States. The highest‐sulfate concentration days for the Atmospheric Integrated Research Monitoring Network (AIRMoN) Pennsylvania site occurred during a similar synoptic pattern when intense convection over the eastern United States was favoured thermodynamically. This study suggests that temporal changes in the large‐scale circulation pattern over North America need to be considered, in addition to changes in precursor emissions, as an explanation for the decreases in sulfate concentrations observed in summertime rains across the eastern United States. Copyright © 2007 Royal Meteorological Society
Dynamic activity dependence of in vivo normal knee kinematics
Authors: Moro‐oka Taka‐aki , Hamai Satoshi , Miura Hiromasa , Shimoto Takeshi , Higaki Hidehiko , Fregly Benjamin J. , Iwamoto Yukihide , Banks Scott A. 
Published: November 2007

AbstractDynamic knee kinematics were analyzed for normal knees in three activities, including two different types of maximum knee flexion. Continuous X‐ray images of kneel, squat, and stair climb motions were taken using a large flat panel detector. CT‐derived bone models were used for model registration‐based 3D kinematic measurement. Three‐dimensional joint kinematics and contact locations were determined using three methods: bone‐fixed coordinate systems, interrogation of CT‐based bone model surfaces, and interrogation of MR‐based articular cartilage model surfaces. The femur exhibited gradual external rotation throughout the flexion range. Tibiofemoral contact exhibited external rotation, with contact locations translating posterior while maintaining 15° to 20° external rotation from 20° to 80° of flexion. From 80° to maximum flexion, contact locations showed a medial pivot pattern. Kinematics based on bone‐fixed coordinate systems differed from kinematics based on interrogation of CT and MR surfaces. Knee kinematics varied significantly by activity, especially in deep flexion. No posterior subluxation occurred for either femoral condyle in maximum knee flexion. Normal knees accommodate a range of motions during various activities while maintaining geometric joint congruency. © Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:428–434, 2008
Prevention of peritendinous adhesions using a hyaluronan‐derived hydrogel film following partial‐thickness flexor tendon injury
Authors: Liu Yanchun , Skardal Aleksander , Shu Xiao Zheng , Prestwich Glenn D. 
Published: November 2007

AbstractPeritendinous adhesions are an important complication of flexor tendon injury. Three hyaluronan (HA)‐derived biomaterials were evaluated for the reduction of peritendinous adhesions following partial‐thickness tendon injury in rabbits. Rabbits (n = 24) were divided into three groups (n = 8 per group), which were used for gross evaluation, histologic assessment, or biomechanical testing. The fourth and third toes from both hindpaws of each rabbit were randomly assigned to one of four treatments: (i) untreated control, (ii) Seprafilm®, (iii) Carbylan™‐SX in situ crosslinked hydrogel, and (iv) preformed Carbylan™‐SX film. Rabbits were sacrificed at 3 weeks postsurgery and evaluated anatomically, histologically, and mechanically. All materials used reduced adhesions relative to untreated controls for all three evaluations. Both the gross anatomic and histologic results revealed that Carbylan™‐SX film was statistically superior to Seprafilm® and Carbylan™‐SX gel in preventing tendon adhesion formation. In biomechanical tests, the Carbylan™‐SX film‐treated hindpaws required the least force to pull the tendon from the sheath. This force was statistically indistinguishable from that required to extrude an unoperated tendon (n = 8). Carbylan™‐SX gel was less effective than Carbylan™‐SX film but superior to Seprafilm® for all evaluations. A crosslinked HA‐derived film promoted healing of a flexor tendon injury without the formation of fibrosis at 3 weeks postoperatively. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:562–569, 2008
Intermittent pneumatic soft tissue compression: Changes in periosteal and medullary canal blood flow
Authors: Park Sang‐Hyun , Silva Mauricio 
Published: November 2007

AbstractWe previously demonstrated that the use of intermittent pneumatic soft tissue compression (IPC) treatment enhanced fracture healing in an animal model, but the exact mechanism remained unknown. The purpose of this study was to determine the local and remote effects of IPC treatment on blood flow within the medullary canal and outside the periosteum of mid‐tibial diaphysis. Blood flow was measured with a Laser Doppler blood flow meter in the lower limbs of 21 rabbits. Laser probes were inserted at three different sites of the mid‐diaphysis on the right tibia: in the medullary canal (n = 21), outside the periosteum on the lateral side (n = 11), and outside the periosteum on the medial side (n = 10). IPC was applied for 30 min through cuffs that were placed around the feet and the lower part of the calf. While applying IPC to the left leg, no changes in blood flow occurred on the right leg (remote changes). However, while applying IPC to the right leg, significant localized changes were found on the right leg, including 47 and 89% increases in total amount of blood flow outside the lateral and medial periosteum, respectively. Although an altered blood flow pattern was observed in the medullary canal, no significant change in total amount of blood flow was observed at this level. In summary, the present study demonstrated that the use of IPC in an intact bone model results in a significant local increase in total blood flow, with minimal measurable effects on the contralateral limb. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:570–577, 2008
Fluorescence molecular tomography enables in vivo visualization and quantification of nonunion fracture repair induced by genetically engineered mesenchymal stem cells
Authors: Zilberman Yoram , Kallai Ilan , Gafni Yossi , Pelled Gadi , Kossodo Sylvie , Yared Wael , Gazit Dan 
Published: November 2007

AbstractFluorescence molecular tomography (FMT) is a novel tomographic near‐infrared (NIR) imaging modality that enables 3D quantitative determination of fluorochrome distribution in tissues of live small animals at any depth. This study demonstrates a noninvasive, quantitative method of monitoring engineered bone remodeling via FMT. Murine mesenchymal stem cells overexpressing the osteogenic gene BMP2 (mMSCs‐BMP2) were implanted into the thigh muscle and into a radial nonunion bone defect model in C3H/HeN mice. Real‐time imaging of bone formation was performed following systemic administration of the fluorescent bisphosphonate imaging agent OsteoSense™, an hydroxyapatite‐directed bone‐imaging probe. The mice underwent imaging on days 7, 14, and 21 postimplantation. New bone formation at the implantation sites was quantified using micro‐computed tomography (micro‐CT) imaging. A higher fluorescent signal occurred at the site of the mMSC‐BMP2 implants than that found in controls. Micro‐CT imaging revealed a mass of mature bone formed in the implantation sites on day 21, a finding also confirmed by histology. These findings highlight the effectiveness of FMT as a functional platform for molecular imaging in the field of bone regeneration and tissue engineering. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:522–530, 2008
Shape‐Memory Effect Controlled by the Crosslinking Topology in Uniaxially‐Deformed Smectic C*Elastomers
Authors: Hiraoka Kazuyuki , Tagawa Naoto , Baba Kiminori 
Published: November 2007

AbstractWe have investigated the shape‐memory effects of uniaxially‐deformed, chiral, smectic C (SmC*) elastomers for two different types of crosslinker, namely, a hydroquinone‐type crosslinker and a rod‐like crosslinker. Mesogens tilt with decreasing temperature from the SmA phase to the SmC*phase in SmC*elastomers synthesized with the hydroquinone‐type crosslinker. As for SmC*elastomers with the rod‐like crosslinker, however, not mesogens but smectic layers are tilted in the smectic phases, because the crosslinker is sufficiently rigid to hinder mesogens from tilting. Because the shape change of such elastomers is coupled to the transformation of molecular alignment, SmC*elastomers synthesized with the hydroquinone‐type crosslinker elongate with increasing temperature in SmC*because of the decrease in molecular‐tilt angle, whereas those with the rod‐like crosslinker have an almost constant sample length in the temperature range of the SmC*phase, despite the rearrangement of the layer structure. Both types of elastomer exhibit a reversible shape change that corresponds to the reversible change in molecular alignment during a heating and cooling process, within successive phase transitions between the isotropic phase and the smectic C*phase.magnified image
Rubbery Thermosets by Ring‐Opening Metathesis Polymerization of a Functionalized Castor Oil and Cyclooctene
Authors: Henna Phillip H. , Larock Richard C. 
Published: November 2007

AbstractRubbery thermosets prepared by ROMP of a modified castor oil containing norbornene moieties and cyclooctene have been synthesized and characterized. The thermosets range from 55 to 85 wt.‐% oil and are flexible, slightly transparent and have a sand‐like hue. Increasing concentration of the modified castor oil in the feed ratio results in an increase in the extracted (unreacted or oligomeric) components in the final thermoset. Thermogravimetric analysis reveals that all of the specimens have temperatures of maximum degradation around 500 °C. DMA and TGA analysis on solvent‐extracted specimens show that the presence of the soluble fractions helps to plasticize the materials and give added thermal stability.magnified image