bluuebunny/crossref_metadata_2025_split huggingface dataset:
Luminescence studies on Ba2ZnSi2O7 : Eu2+ phosphors crystals
Authors: Yao Shan‐shan , Li Yuan‐yuan , Xue Li‐hong , Yan You‐wei , You Yan 
Published: September 2009

AbstractA novel blue green‐emitting phosphor Ba2ZnSi2O7 : Eu2+ was prepared by combustion synthesis method and an efficient bluish green emission under from ultraviolet to visible light was observed. The emission spectrum shows a single intensive band centered at 503 nm, which corresponds to the 4f65d1 → 4f7 transition of Eu2+. The excitation spectrum is a broad band extending from 260 to 465 nm, which matches the emission of ultraviolet light‐emitting diodes (UV‐LEDs). The effect of doped Eu2+ concentration on the emission intensity of Ba2ZnSi2O7 : Eu2+ was also investigated. The result indicates that Ba2ZnSi2O7 : Eu2+ can be potentially useful as a UV radiation‐converting phosphor for white light‐emitting diodes. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and Characterisation of a New Series of Bistable Iron(II) Spin‐Crossover 2D Metal–Organic Frameworks
Authors: Martínez Víctor , Gaspar Ana Belén , Muñoz M. Carmen , Bukin Gennadiy V. , Levchenko Georgii , Real José Antonio 
Published: September 2009

AbstractTwelve coordination polymers with formula {Fe(3‐Xpy)2[MII(CN)4]} (MII: Ni, Pd, Pt; X: F, Cl, Br, I; py: pyridine) have been synthesised, and their crystal structures have been determined by single‐crystal or powder X‐ray analysis. All of the fluoro and iodo compounds, as well as the chloro derivative in which MII is Pt, crystallise in the monoclinic C2/m space group, whereas the rest of the chloro and all of the bromo derivatives crystallise in the orthorhombic Pnc2 space group. In all cases, the iron(II) atom resides in a pseudo‐octahedral [FeN6] coordination core, with similar bond lengths and angles in the various derivatives. The major difference between the two kinds of structure arises from the stacking of consecutive two‐dimensional {Fe(3‐Xpy)2[MII(CN)4]}∞ layers, which allows different dispositions of the X atoms. The fluoro and chloro derivatives undergo cooperative spin crossover (SCO) with significant hysteretic behaviour, whereas the rest are paramagnetic. The thermal hysteresis, if X is F, shifts toward room temperature without changing the cooperativity as the pressure increases in the interval 105 Pa–0.5 GPa. At ambient pressure, the SCO phenomenon has been structurally characterised at different significant temperatures, and the corresponding thermodynamic parameters were obtained from DSC calorimetric measurements. Compound {Fe(3‐Clpy)2[Pd(CN)4]} represents a new example of a “re‐entrant” two‐step spin transition by showing the Pnma space group in the intermediate phase (IP) and the Pnc2 space group in the low‐spin (LS) and high‐spin (HS) phases.
Centriole symmetry: A big tale from small organisms
Authors: Riparbelli Maria Giovanna , Dallai Romano , Mercati David , Bu Yun , Callaini G. 
Published: September 2009

AbstractCentrioles are microtubule‐based cylindrical organelles with a 9‐fold symmetry. They are essential for axoneme formation in cilia and flagella and for centrosome organization. In the basal hexapods Acerentomon microrhinus, we discovered unusually large centrioles composed of 14 doublet microtubules that serve as templates for cilia and flagella and organize mitotic and meiotic spindles. These observations challenge the long‐standing view that centriole symmetry is highly conserved among eukaryotes. Strikingly, daughter centrioles contain a transient cartwheel that is lost after maturation. The length of radial spokes is like that found in 9‐fold cartwheels, whereas the diameter of the hub varies according to the dimensions of the centriole cylinder. This suggests that the hub may dictate the master plan for centriole geometry. Finally, the finding that 14‐doublet centrioles arise from 9‐doublet mothers points to an alternative model for centriole assembly. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Complex version of high performance computing LINPACK benchmark (HPL)
Authors: Barrett R. F. , Chan T. H. F. , D'Azevedo E. F. , Jaeger E. F. , Wong K. , Wong R. Y. 
Published: September 2009

AbstractThis paper describes our effort to enhance the performance of the AORSA fusion energy simulation program through the use of high‐performance LINPACK (HPL) benchmark, commonly used in ranking the top 500 supercomputers. The algorithm used by HPL, enhanced by a set of tuning options, is more effective than that found in the ScaLAPACK library. Retrofitting these algorithms, such as look‐ahead processing of pivot elements, into ScaLAPACK is considered as a major undertaking. Moreover, HPL is configured as a benchmark, but only for real‐valued coefficients. We therefore developed software to convert HPL for use within an application program that generates complex coefficient linear systems. Although HPL is not normally perceived as a part of an application, our results show that the modified HPL software brings a significant increase in the performance of the solver when simulating the highest resolution experiments thus far configured, achieving 87.5 TFLOPS on over 20 000 processors on the Cray XT4. Copyright © 2009 John Wiley & Sons, Ltd.
Automated organelle‐based colocalization in whole‐cell imaging
Authors: Woodcroft Ben J. , Hammond Luke , Stow Jennifer L. , Hamilton Nicholas A. 
Published: September 2009

AbstractThe use of fluorescence microscopy to investigate protein colocalization is an invaluable tool for understanding subcellular structures and their associated proteins. However, current techniques are largely limited to two‐dimensional (2D) imaging and often require manual segmentation. Here, we present OBCOL, a methodology to automatically segment and quantify protein colocalization not within an image as a whole but on all individual punctuate organelles within a 3D multichannel image. A wide variety of colocalization statistics may then be calculated on the objects found, and features reported for each such as position, degree of overlap between channels, and number of component objects. OBCOL was validated on imaging of two fluorescent markers (Dextran, EGF) in 3D microscopy imaging. OBCOL's application was then exemplified by investigating the colocalization of three fluorescently tagged proteins (VAMP3, Rab11, and transferrin) on recycling endosomes in mammalian cells. The methodology showed for the first time the diversity of endosomes labeled with one or more of these proteins and quantitatively demonstrated the degree of overlap among these proteins in individual recycling endosomes. The consistent segregation of these markers provides novel evidence for the subcompartmentalization of recycling endosomes. OBCOL is a flexible methodology for 3D multifluorophore image analysis. This study clearly demonstrated its value for investigating subcellular structures and their constituent proteins. © 2009 International Society for Advancement of Cytometry
Tm3+‐Doped Y2O3 Nanocrystals: Rapid Hydrothermal Synthesis and Luminescence
Authors: Devaraju Murukanahally Kempaiah , Yin Shu , Sato Tsugio 
Published: September 2009

AbstractTm3+‐doped Y2O3 nanocrystals were prepared via hydrothermal conditions at high autogenous pressure (ca. 40 MPa) using batch reactors at 220 and 250 °C for very short periods of reaction time (10 min). The as‐prepared materials were identified as Y(OH)3 nanoparticles. The precursor materials with two types of morphologies, such as sphere and rod‐shaped particles were prepared at 220 and 250 °C within 10 min. The sizes of the as‐prepared sphere particles are 10–15 nm in diameter, whereas the rod‐shaped particles show 15–20 nm in diameter and 0.1–0.2 μm in lengths. The precursor materials were calcined at 500 and 800 °C for 5 h in air to obtain (3 mol‐%) Tm3+‐doped Y2O3 nanocrystals. For the characterization, XRD, FESEM, EDS and TG‐DTA were employed. The photoluminescence spectra of sphere and rod‐shaped particles show higher blue emission at 450 nm than the reference sample. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Molecular and Crystal Structures of Cp*M(S2N2) (M = Co, Rh, Ir) and Related Compounds
Authors: Matuska Vit , Tersago Karla , Kilian Petr , Van Alsenoy Christian , Blockhuys Frank , Slawin Alexandra M. Z. , Woollins J. Derek 
Published: September 2009

AbstractCp*Rh(S2N2) was prepared as a microcrystalline solid by using [S4N3]Cl in liquid ammonia or [nBu2Sn(S2N2)]2. It was characterised by NMR, IR and Raman spectroscopy andmass spectrometry. Low‐temperature crystal structures of Cp*Co(S2N2) and Cp*Ir(S2N2) were determined. The experimental characterisation of the Cp*M(S2N2) complexes was complemented by calculated geometries and bond orders at the DFT/B1B95 level of theory. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
16‐Electron (Arene)ruthenium Complexes with Superbasic Bis(imidazolin‐2‐imine) Ligands and Their Use in Catalytic Transfer Hydrogenation
Authors: Glöge Thomas , Petrovic Dejan , Hrib Cristian , Jones Peter G. , Tamm Matthias 
Published: September 2009

AbstractThe ligands N,N′‐bis(1,3,4,5‐tetramethylimidazolin‐2‐ylidene)‐1,2‐ethanediamine (BLMe) and N,N′‐bis(1,3‐diisopropyl‐4,5‐dimethylimidazolin‐2‐ylidene)‐1,2‐ethanediamine(BLiPr) react with [(η5‐C5Me5)RuCl]4 to afford cationic 16‐electron half‐sandwich complexes [(η5‐C5Me5)Ru(BLR)]+ (R = Me, 3; R = iPr, 4), which resist coordination of the chloride counterion because of the strong electron‐donating ability of the diimine ligands. Upon reaction with [(η6‐C6H6)RuCl2]2 or [(η6‐C10H14)RuCl2]2, these ligands stabilize dicationic 16‐electron benzene and cymene complexes of the type [(η6‐C6H6)Ru(BLR)]2+ (R = Me, 5; R = iPr, 6) and [(η6‐C10H14)Ru(BLR)]2+ (R = Me, 7; R = iPr, 8). The X‐ray crystal structure of [5]Cl2 reveals the absence of any direct Ru–Cl interaction, whereas a long Ru–Cl bond, supported by two CH···Cl hydrogen bonds, is observed for [(6)Cl]Cl in the solid state. Treatment of the dichlorides of 6 and 8 with NaBF4 affords [6](BF4)2 and [8](BF4)2, which are composed of individual dications and tetrafluoroborate ions with no direct Ru–F interaction. All complexes catalyze the transfer hydrogenation of acetophenone in boiling 2‐propanol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Polyurethane Membranes Used in Integrated Electronic Tongue for the Recognition of Tea and Herbal Products
Authors: Ciosek Patrycja , Kraszewska Zofia , Wròblenski Wojciech 
Published: September 2009

AbstractPolyurethane membranes as polymeric materials doped with various electroactive components are applied to the fabrication of miniaturized electrodes on solid‐state support. The responses of the prepared integrated sensor array are analyzed with the use of principal components analysis and principal components regression, in order to perform the recognition of various types of beverages (black tea/red tea/green tea/herbals) and the discrimination among various kinds of them (brand of a product).
Assessment of Ion‐Ionophore Complex Diffusion Coefficients in Solvent Polymeric Membranes
Authors: Zook Justin M. , Bodor Sándor , Lindner Ernő , Tóth Klára , Gyurcsányi Róbert E. 
Published: September 2009

AbstractChronoamperometric (CA) and chronopotentiometric (CP) transients have been used previously for the determination of the diffusion coefficients of free ionophores in ion‐selective liquid membranes. In this work, the CA and CP transients are utilized to determine the diffusion coefficients of a variety of ion‐ionophore complexes in these membranes. The conditions under which the ion‐ionophore complex diffusion coefficients can be determined from the CA and CP transients are discussed. For most ionophores, the ion‐ionophore complex diffusion coefficients were found to be slightly smaller or similar to the previously calculated free ionophore diffusion coefficients. However, for a couple of ionophores, the ion‐ionophore complex diffusion coefficients were found to be significantly smaller than expected. Significant ion‐pair formation in the membranes can explain this disparity.
Quantification of economic, environmental and operational benefits due to significant penetration of Microgrids in a typical LV and MV Greek network
Authors: Hatziargyriou N. D. , Anastasiadis A. G. , Tsikalakis A. G. , Vasiljevska J. 
Published: September 2009

AbstractThe effect of the use of a Microgrid Central Controller (MGCC) to achieve co‐ordinated operation of various DG sources, storage devices and controllable loads with regards to the potential economic benefits and the power losses avoided in the local network is presented. Additionally, the effect of connecting numerous typical Microgrids in a typical medium voltage (MV) network regarding power losses and the emissions avoided is studied. The emissions avoidance calculation is based on the marginal emissions curve of the upstream network, quantifying also the calculated losses reduction impact on emissions avoidance. The presented results, based on a variety of realistic market prices time‐series, various levels of renewable energy resource (RES) production and demand from different seasons, show clear benefits in terms of both losses and emissions avoidance. Finally, this paper performs a sensitivity analysis on the potential impact of the DG topology within a Microgrid on losses and emissions avoidance. Copyright © 2009 John Wiley & Sons, Ltd.
Control Loop Design and Control Performance Study on Direct Internal Reforming Solid Oxide Fuel Cell
Authors: Zhang H. , Weng S. , Su M. 
Published: September 2009

AbstractA solid oxide fuel cell (SOFC) stack is a complicated nonlinear power system. Its system model includes a set of partial differential equations that describe species, mass, momentum and energy conservation, as well as the electrochemical reaction models. The validation and verification of the control system by experiment is very expensive and difficult. Based on the distributed and lumped model of a one‐dimensional SOFC, the dynamic performance with different control loops for SOFC is investigated. The simulation result proves that the control system is appropriate and feasible, and can effectively satisfy the requirement of variable load power demand. This simulation model not only can prevent some latent dangers of the fuel cell system but also predict the distributed parameters' characteristics inside the SOFC system.
An information and communication technologies–based framework for enhancing project management education through competence assessment and development
Authors: Makatsoris Charalampos 
Published: September 2009

AbstractAdvances in information and communication technologies (ICT) have had a great impact on ways of working and communicating across all industrial sectors, including education. However, the education sector has been lacking adoption of potentially key technologies that can help improve delivery of modules and the overall learning experience of students. This research aims at addressing the important problem of understanding the strengths, weaknesses, current competences, and existing soft skills of new Masters of Science students starting a course on Project Management. This information is important for instructors as they can adapt and optimize delivery of such modules, enhance the overall learning experience, and assist the module leader in enhancing content. Also this information is not readily available to module leaders, and these competencies and skills cannot be assessed by traditional academic means. To address this problem a new process is proposed that uses an ICT system called Cycloid as its “backbone.” This article describes a new process and demonstrates it in a practical application. This is done through a study involving a number of students at the School of Engineering and Design at Brunel University who took the course during the 2007–2008 academic year. The aim of the study was to assess and demonstrate the feasibility of the proposed process. Results demonstrate the feasibility of the proposed process for implementation in higher education. © 2009 Wiley Periodicals, Inc.
Baimantuoluosides A – C, Three New Withanolide Glucosides from the Flower of Datura metel L.
Authors: Kuang Haixue , Yang Bingyou , Tang Ling , Xia Yonggang , Dou Deqiang 
Published: September 2009

AbstractIn search for bioactive compounds from the flower of Datura metel L., three new withanolide glucosides, namely baimantuoluosides A, B, and C (1–3, resp.) were isolated. Enzymatic hydrolysis of 1–3 afforded the corresponding aglycones 1a, 2a, and 3a, respectively. The structures of the new compounds were elucidated as (5α,6α,7α,12β,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D‐glucopyranoside (1), (5α,6α,7α,12α,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D‐glucopyranoside (2), (5α,6α,7α,22R)‐5‐hydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D‐glucopyranoside (3) on the basis of chemical and physicochemical evidence, and are further confirmed by the structure determination by X‐ray diffraction of withanolide aglycone 1a.
Synthesis of Regioisomeric Functionalized Benzodifurans and Angelicins
Authors: Quezada Elías , Delogu Giovanna , Viña Dolores , Santana Lourdes , Podda Gianni , Joao Matos Maria , Picciau Carmen 
Published: September 2009

AbstractArenofurans have important biological and pharmacological activities. Compared to benzofurans, the reports on the synthesis of benzodifurans are rather limited. Here, we report the synthesis of a linear and an angular 3,3′‐bis(carboxymethyl)substituted benzodifuran and 4′‐carboxymethyl‐substituted angelicins from phloroglucinol, using 4‐halomethyl‐substituted dipyrones as key intermediates in the synthetic route. This strategy shows that the stability of a pyrone ring depends on the type of substituent at C(4) and the conditions used.
Diterpenoids from the Hainan Soft Coral Sinularia parva
Authors: Li Yan , Gao An‐Hui , Huang Hui , Li Jia , Mollo Ernesto , Gavagnin Margherita , Cimino Guido , Gu Yu‐Cheng , Guo Yue‐Wei 
Published: September 2009

AbstractTwo new cembrane diterpenes, sinulaparvalides A and B (1 and 2, resp.), which contain an intriguing seven‐membered lactone moiety, along with the four known related cembranoids 3–6, were isolated from the Hainan soft coral Sinularia parva. The structures of compounds 1 and 2 were established by spectroscopic methods, mainly on the basis of 2D‐NMR techniques, and were confirmed by single‐crystal X‐ray diffraction analysis. The in vitro cytotoxic activities of these compounds were tested on human colon carcinoma (HCT‐116), human promyelocytic leukemia (HL‐60), and human lung carcinoma (A‐549) tumor cell lines.
Lingshuine, an Unexpected Passerini Product from the Hainan Sponge Axinyssa variabilis
Authors: Xue Duo‐Qing , Mollo Ernesto , Cimino Guido , Guo Yue‐Wei 
Published: September 2009

AbstractLingshuine (1), a novel sesquiterpene amide, along with three known N‐containing compounds, 2–4, have been isolated from the Hainan sponge Axinyssa variabilis. The structure of 1 was elucidated by detailed analysis of the spectroscopic data and by chemical methods. Lingshuine represents the first example of a Passerini product formed during the isolation process.
Two New Withanolides from Physalis peruviana
Authors: Fang Sheng‐Tao , Li Bo , Liu Ji‐Kai 
Published: September 2009

AbstractTwo new perulactone‐type withanolides, named perulactone C (1) and perulactone D (2), together with four known compounds, perulactone (3), perulactone B (4), blumenol A, and (+)‐(S)‐dehydrovomifoliol, were isolated from the aerial parts of Physalis peruviana. The structures of the new compounds were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS.
Total Synthesis of (+)‐Machaeriols B and C and of Their Enantiomers with a Cannabinoid Structure
Authors: Lee Hee Jin , Lee Yong Rok , Kim Sung Hong 
Published: September 2009

AbstractAn efficient and concise synthesis of the biologically interesting (+)‐machaeriol B (2) and its enantiomer 5 was accomplished from O‐phenylhydroxylamine (7) in four steps (Scheme 2). In addition, the first total synthesis of natural (+)‐machaeriol C (3) and its enantiomer 6 was achieved from the readily available ester 15 in eight steps (Scheme 4). The key strategies in the syntheses of 2 and 5 involved benzofuran formation through a [3,3]‐sigmatropic rearrangement and trans‐hexahydrodibenzopyran formation by a domino aldol‐type/hetero‐Diels–Alder reaction. In the case of 3 and 6, the key steps were stilbene formation by a Horner–Wadsworth–Emmons reaction and trans‐hexahydrodibenzopyran formation by domino reactions.
Synthesis and Anti‐HIV‐1 Evaluation of New Sonogashira‐Modified Emivirine (MKC‐442) Analogues
Authors: Danel Krzysztof , Jørgensen Per T. , Pedersen Erik B. , La Colla Paolo , Collu Gabriella , Loddo Roberta 
Published: September 2009

AbstractThe MKC‐442 analogue 6‐(3,5‐dimethylbenzyl)‐5‐ethyluracil substituted with a (propargyloxo)methyl group at N(1) has previously been found highly active against HIV‐1. The CC bond in the substituent at N(1) is here utilized in a series of chemical reactions in order to develop new agents with higher activity against HIV‐1‐resistant mutants. The syntheses involved Pd‐catalyzed C,C‐coupling reactions, addition of disulfides, and click chemistry on the terminal CC bond as well as addition of bromine to the so formed internal CC bonds. Sonogashira coupling were performed with silyl‐derivatized iodobenzyl alcohols which, after deprotection, were oxidized to aldehydes by means of IBX. The isomeric alcohol 37 was obtained in the Sonogashira reaction of propargyl alcohol with the N(1)‐substituted (4‐iodobenzyloxy)methyl derivative of the above mentioned uracil. Compound 37 turned out to be the most effective compound against problematic HIV‐1 mutants. The general observation in the present work is that a combination of alkyne and aryl in the substituent at N(1) leads to highly active compounds against HIV‐1.
Benzodiazepine Alkaloids from Marine‐Derived Endophytic Fungus Aspergillus ochraceus
Authors: Cui Chuan‐Ming , Li Xiao‐Ming , Li Chun‐Shun , Sun Hao‐Fen , Gao Shu‐Shan , Wang Bin‐Gui 
Published: September 2009

AbstractA new fungus‐derived benzodiazepine analogue, 2‐hydroxycircumdatin C (1), and a compound which has been isolated from a natural resource for the first time, but has been previously synthesized, namely (11aS)‐2,3‐dihydro‐7‐methoxy‐1H‐pyrrolo[2,1‐c][1,4]benzodiazepine‐5,11(10H,11aH)‐dione (2), along with five structurally related known alkaloids (3–7), were isolated from Aspergillus ochraceus, an endophytic fungus derived from the marine brown alga Sargassum kjellmanianum. Their structures were established on the basis of spectroscopic methods. The absolute configuration of 1 was determined through CD evidence. Compound 1 displayed significant DPPH radical‐scavenging activity with an IC50 value of 9.9 μM, which is 8.9‐fold more potent than that of butylated hydroxytoluene (BHT), a well‐known synthetic positive control.