bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicting Climate Change: Lessons From Reductionism, Emergence, and the Past
Authors: Harrison Stephan , Stainforth Dave 
Published: April 2009

Climate and Earth system models are the only tools used to make predictions of future climate change. Such predictions are subject to considerable uncertainties, and understanding these uncertainties has clear and important policy implications. This Forum highlights the concepts of reductionism and emergence, and past climate variability, to illuminate some of the uncertainties faced by those wishing to model the future evolution of global climate.General circulation models (GCMs) of the atmosphere‐ocean system are scientists' principal tools for providing information about future climate. GCMs consequently have considerable influence on climate change–related policy questions. Over the past decade, there have been significant attempts, mainly by statisticians and mathematicians, to explore the uncertainties in model simulations of possible futures, accompanied by growing debate about the interpretation of these simulations as aids in societal decisions. In this Forum, we discuss atmosphere‐ocean GCMs in the context of reductionist and emergent approaches to scientific study.
RELATIONSHIP BETWEEN WATER ACTIVITY, DEFORMATION SPEED, AND CRISPNESS CHARACTERIZATION
Authors: CASTRO‐PRADA EVA M. , PRIMO‐MARTÍN CRISTINA , MEINDERS MARCEL B.J. , HAMER ROB J. , VAN VLIET TON 
Published: April 2009

ABSTRACT Very little is known on the rate dependency of the fracture behavior of crispy products as a function of water activity (Aw). Therefore, the effect of deformation speed on instrumental and sensory crispness was studied as a function of Aw. Deformation speed clearly affects the transition Aw range from crispy to non‐crispy. At low deformation speed, the critical Aw was 0.40 ± 0.02 and at high deformation speed between 0.5 and 0.6. The transition was completed at an Aw = 0.56 ± 0.10 and 0.74 ± 0.00 for the low and high speed, respectively. The transition of sensory crispness at regular biting speed started at Aw = 0.48 and was completed at Aw = 0.75. The deformation speed effect is assumed to be caused by the viscoelastic nature of the material in the transition region causing it to behave locally relatively more viscous at low deformation speed and relatively more elastic at high deformation speed. This behavior depends on the plasticizer content, thus, Aw. For the product used in this study, the instrumental deformation speed that best correlate to sensory data is 10 to 40 mm/s. Sensory tests show that crispy attributes are perceived more intense when biting at higher speed.PRACTICAL APPLICATIONSA good characterization of the water activity (Aw) range over which crispness of a food product is lost is of great practical importance. The present study describes the effect of deformation speed and Aw on crispness characteristics as determined by instrumental and sensory measurements. Crispness characteristics were found to depend not only on Aw but also on deformation speed. The Aw at which the crispy material started to lose it crispness started at lower values of Aw for the low deformation speed. Instrumental data should follow a similar trend as sensory crispness as function of Aw. At high deformation speed, instrumental sound data were more closely related to loss of crispness than force data, mainly caused by problems in the force registration. To get a good correlation of sensory and instrumental data, a correct deformation speed should be selected for this purpose. Sensory tests at different biting/chewing speed were done. Crispness attributes were scored lower when Aw was higher, as well as when decreasing the biting/chewing speed.
Activated charcoal‐loaded composite membranes of sodium alginate in pervaporation separation of water‐organic azeotropes
Authors: Aminabhavi T. M. , Patil M. B. , Bhat S. D. , Halgeri A. B. , Vijayalakshmi R. P. , Kumar P. 
Published: April 2009

AbstractComposite membranes of sodium alginate prepared by incorporating nanosized‐activated charcoal particles were prepared and characterized for the extent of cross‐linking, thermal stability, and mechanical strength properties using Fourier transform infrared, differential scanning calorimetry, and universal testing machine, respectively. The membranes were tested for pervaporation (PV) dehydration of isopropanol (IPA), ethanol (EtOH), 1,4‐dioxane (1,4‐D), and tetrahydrofuran (THF) at their azeotropic compositions. Improved PV performances of the composite membranes were observed compared with plain sodium alginate membrane for all the azeotropes. Sorption was studied to evaluate the extent of interactions between liquids and membranes as well as degree of swelling of the membranes in the chosen aqueous‐organic mixtures. Adding different amounts of activated charcoal into NaAlg offered high water selectivity values of 99.7, 99.1, 99.4, and 99.41%, respectively, for IPA, THF, 1,4‐D, and EtOH. Arrhenius activation parameters were computed from the temperature versus flux plots, which showed systematic trends for different liquids that depended upon their interactions with membranes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Performance studies of heterogeneous ion exchange membranes in the removal of bivalent metal ions in an electrodialysis stack
Authors: Ray P. 
Published: April 2009

AbstractHeterogeneous anion and cation exchange membranes have been prepared by solution casting technique with poly(vinyl chloride) as inert binder and anion/cation exchange resins (−300 + 400 mesh) in a blend ratio of 60 : 40. The membranes were characterized with respect to their physical, mechanical, and electrochemical behavior. Anion and cation exchange membranes (10 cell pairs) were packed in an electrodialysis stack in a parallel plus series flow pattern. Desalting experiments were carried out with four different salt solutions, such as calcium chloride, magnesium chloride, cupric chloride, and nickel chloride (varying in their total dissolved solid from 500 to 1000 ppm), at different applied potentials and flow rates. The resultant current, percentage reduction in total dissolved solid, current efficiency, and energy consumption were calculated. The maximum current density in the electrodialysis stack was observed for calcium chloride solution and at any applied potential and flow rate the percentage reduction in total dissolved solid for Ca++ > Cu++ > Ni++ > Mg++. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synergistic enhancement in tensile strength and ductility of ABS by using recycled PETG plastic
Authors: Li Bo , Zhang Xinlan , Zhang Qin , Chen Feng , Fu Qiang 
Published: April 2009

AbstractAcrylonitrile–butadiene–styrene (ABS)/poly(ethylene glycol‐co‐cyclohexane‐1,4‐dimethanol terephthalate) (PETG) blends with various ratios at three different processing temperatures were prepared. A significant synergistic enhancement in tensile strength and ductility for a wide range of compositions was achieved. Phase morphology with droplets, fibrils, and co‐continuity was obtained, depending on the composition and processing temperature. Changes of the phase domain sizes and the composition range of co‐continuity were found with the change of processing temperature and could be explained by temperature‐induced coalescence effects. The synergism and toughening mechanism were discussed based on the temperature‐morphology‐property relationships. Since the PETG used is a recycled plastic from the waste films and plates, our work provides a new and inexpensive means for the modification of ABS with high mechanical properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Polymeric calcium phosphate cements incorporated with poly‐γ‐glutamic acid: Comparative study of poly‐γ‐glutamic acid and citric acid
Authors: Kim Sung Soo , Seo Mijung , Chung Jin Wha , Kwon Soon Yong , Kim Yong‐Sik 
Published: April 2009

AbstractPolymeric calcium phosphate cements (PCPC) derived from biodegradable poly‐γ‐glutamic acid (γ‐PGA) were prepared in an attempt to improve the mechanical strength of calcium phosphate cement (CPC). The characteristics of the PCPCs were compared with those of cement incorporated with citric acid. The diametral tensile and compressive strengths of the CPC incorporated with γ‐PGA were significantly higher than that of cement incorporated with citric acid at equivalent concentrations (P < 0.05). The maximal diametral tensile and compressive strengths of the CPC incubated for 1 week in physiological saline solution were approximately 18.0 and 50.0 MPa, respectively. However, the initial setting time of the PCPC was slower than that of CPC incorporated with citric acid. The formation of ionic complexes between calcium ions and γ‐PGA was observed using FTIR spectroscopy. Hydroxyapatite (HA) formation was retarded by γ‐PGA incorporation according to scanning electronic microscopy (SEM) and powder X‐ray diffraction (XRD) observations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of poly(vinyl alcohol)‐graft‐poly(ε‐caprolactone) and poly(vinyl alcohol)‐graft‐poly(lactide) in melt with magnesium hydride as catalyst
Authors: Guerrouani Nadia , Mas André , Schué François 
Published: April 2009

AbstractGrafting of poly(ε‐caprolactone) (PCL) and poly(lactide) (PLA) chains on poly(vinyl alcohol) backbone (PVA degree of hydrolysis 99%) was investigated using MgH2 environmental catalyst and melt‐grown ring‐opening polymerization (ROP) of ε‐caprolactone (CL) and L‐lactide (LA), that avoiding undesirable toxic catalyst and solvent. The ability of MgH2 as catalyst as well as yield of reaction were discussed according to various PVA/CL/MgH2 and PVA/LA/MgH2 ratio. PVA‐g‐PCL and PVA‐g‐PLA were characterized by 1H‐ and 13C‐NMR, DSC, SEC, IR. For graft copolymers easily soluble in tetrahydrofuran (THF) or chloroform, wettability and surface energy of cast film varied in relation with the length and number of hydrophobic chains. Aqueous solution of micelle‐like particles was realized by dissolution in THF then addition of water. Critical micelle concentration (CMC) decreased with hydrophobic chains. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Ultrasonic sealing of polyester and spectra fabrics using thermo plastic properties
Authors: Ghosh Subhas , Reddy Renuka 
Published: April 2009

AbstractA study of polyethylene terephthalate (PET) and spectra fabric's ultrasonic sealing (welding) potential was conducted using both continuous and discontinuous ultrasonic welding machines. The effects of two important welding parameters such as weld pressure and weld time were investigated on the fabric's bond strength. Depending on the thermal property of the polymer, a certain level of temperature rise during sealing is required to soften the fibers, to facilitate the development of rows of welding points between the fabric layers. This happens under the compaction due to weld pressure. The gaps between the points are so narrow that the rows appear to be a complete sealing of the layers. Excessive melting under weld pressure, to create melt bonding caused polymer degradation and poor bond strength. Scanning Electron Microcopy images and the temperature measurements at the fabric's interface were used to examine the bond locations of the fabric. Differential Scanning Calorimetry analyses of PET and spectra fabrics have been used to examine the thermal behavior of the ultrasonic sealed material. Adequate seam strength was achieved under certain conditions of sealing for both the fabrics using both continuous and discontinuous methods of operation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A novel process to isolate fibrils from cellulose fibers by high‐intensity ultrasonication, Part 1: Process optimization
Authors: Wang Siqun , Cheng Qingzheng 
Published: April 2009

AbstractCellulose fibrils of microscale and nanoscale sizes have great strength and hence furnish the possibility of reinforcing polymers. Fibrils can be isolated from natural cellulose fibers by chemical or mechanical methods. However, the existing procedures either produce low yields or severely degrade the cellulose and, moreover, are not environment friendly or energy efficient. The purpose of this study was to develop a novel process that uses high‐intensity ultrasonication (HIUS) to isolate fibrils from several cellulose resources. Six factors that may affect the efficiency of fibrillation, including power, temperature, time, concentration, size, and distance, have been considered and discussed. HIUS treatment can produce very strong mechanical oscillating power; therefore, the separation of cellulose fibrils from its biomass is possible by the action of hydrodynamic forces of the ultrasound. Water‐retention value and volume change were used to evaluate and optimize the process parameters. The degree of fibrillation of the cellulose fibers treated by HIUS was significantly increased. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Electrokinetic properties of polypropylene‐layered silicate nanocomposite fibers
Authors: Smole Majda Sfiligoj , Stakne Kristina , Kleinschek Karin Stana , Kurecic Manja , Bele Marjan , Svetec Diana Gregor , Ribitsch Volker 
Published: April 2009

AbstractNanocomposite fibers based on polypropylene (PP) polymer were prepared with different content of nanofiller. Filaments were spun from an isotactic iPP homopolymer. Montmorillonite modified by N,N‐dimethyl‐N,N dioctadecylammonium cations was used for preparation of PP nanocomposite fibers. A PP grafted with acrylic acid was added as a coupling agent. Nanocomposite fibers were characterized, i.e., the surface morphology of PP nanocomposite fibers was observed and surface properties were defined by electrokinetic properties determination by zeta potential measurements. For particle distribution observation the plasma etching was involved as a method for sample preparation. The addition of nanoparticles has an impact on ZP value of nanofilled fibers, however, isoelectric point IEP is not significantly influenced by different concentrations of nanofiller. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
In vitro effects of 2‐methoxyestradiol on cell numbers, morphology, cell cycle progression, and apoptosis induction in oesophageal carcinoma cells
Authors: Thaver Veneesha , Lottering Mona‐Liza , van Papendorp Dirk , Joubert Annie 
Published: April 2009

AbstractThe influence of 2‐methoxyestradiol (2‐ME) was investigated on cell numbers, morphology, cell cycle progression, and apoptosis induction in an oesophageal carcinoma cell line (WHCO3). Dose‐dependent studies (1 × 10−9M–1 × 10−6M) revealed that 2‐ME significantly reduced cell numbers to 60% in WHCO3 after 72 h of exposure at a concentration of 1 × 10−6M compared to vehicle‐treated cells. Morphological studies entailing light‐, fluorescent‐, as well as transmission electron microscopy (TEM) confirmed 2‐ME's antimitotic effects. These results indicated hallmarks of apoptosis including cell shrinkage, hypercondensation of chromatin, cell membrane blebbing, and apoptotic bodies in treated cells. Flow cytometric analyses demonstrated an increase in the G2/M‐phase after 2‐ME exposure; thus preventing cells from proceeding through the cell cycle. β‐tubulin immunofluorescence revealed that 2‐ME caused spindle disruption. In addition, increased expression of death receptor 5 protein was observed further supporting the proposed mechanism of apoptosis induction via the extrinsic pathway in 2‐ME‐exposed oesophageal carcinoma cells. Copyright © 2009 John Wiley & Sons, Ltd.
A Kinetically Mechanistic Investigation of Oxidation of 1,4‐Butanediamine by Ag(III) Complex in Alkaline Medium
Authors: SONG Changying , SHAN Jinhuan , Shen Shigang , Sun Hanwen 
Published: April 2009

Abstract Kinetics and mechanism of oxidation of 1,4‐butanediamine by a Ag(III) complex were studied spectrophotometrically in alkaline medium at constant ion strength. The reaction shows first order with respect to the Ag(III) complex and 1,4‐butanediamine respectively. The second order rate constant, k′, increased with the increasing in [OH−], and decreased with the increasing in [IO4−]. A plausible mechanism was proposed from the kinetics study. The rate equations derived from the mechanism can explain all experimental phenomena. The activation parameters were calculated.
Theoretical Studies on the Infrared Vibrational Spectra, Thermodynamic Properties and Nuclear Magnetic Resonance Spectra for Polynitro‐1,3‐bishomopentaprismanes
Authors: QIU Limei , GONG Xuedong , WANG Guixiang , ZHENG Jian , XIAO Heming 
Published: April 2009

AbstractBased on the optimized molecular geometries at the DFT‐B3LYP/6‐31G∗︁ level, IR spectra, thermodynamic functions, as well as 13C and 1H NMR chemical shifts, were obtained and discussed for polynitro‐1,3‐bishomo‐pentaprismanes (PNBPP). The comparison of the calculated IR frequencies and NMR chemical shifts showed considerable agreements with the available experimental results. IR regions, 13C and 1H NMR chemical shifts of PNBPP were assigned. The relationships of the thermodynamic functions with temperature and the number of nitro groups were discussed, and it was found that the latter showed a good group additivity rule. These calculated data and discussions would be helpful for the further study of PNBPP.
Catalytic Combustion of Ethyl Acetate over Nanostructure Cobalt Supported ZSM‐5 Zeolite Catalysts
Authors: NIAEI Aligholi , SALARI Dariush , HOSSEINI Seyed Ali , KHATAMIAN Masumeh , JODAEL Azadeh 
Published: April 2009

Abstract Gas phase catalytic combustion of ethyl acetate, as one of volatile organic compounds (VOC), was studied on nanostructure ZSM‐5, HZSM‐5 and Co‐ZSM‐5 with different cobalt loadings. Nanostructure of ZSM‐5 was determined by XRD, SEM and TEM. Catalytic studies were carried out under atmospheric pressure in a fixed bed reactor. Results showed that the Co‐ZSM‐5 catalysts had better activity than others and at temperatures below 350 °C, amount of Co loading was more effective on catalytic activity. The order of conversion of ethyl acetate over different Co loading is as follows: Co‐ZSM‐5 (0.75 wt%)<Co‐ZSM‐5 (1.5 wt%)<Co‐ZSM‐5 (15 wt%)<Co‐ZSM‐5 (2.8 wt%). Besides the higher the inlet concentration of ethyl acetate, the lower the conversion yield, and oxygen concentration in catalytic oxidation conditions has not so large influence on conversion. Furthermore, the presence of water vapor in inlet gaseous feed has an inhibitive effect on ethyl acetate conversion and at the temperatures above 400?C, the effect decreases.
Homogeneous DNA Detection Based on Fluorescence Quenching by Nanoparticles in Single‐step Format: Target‐Induced Configuration Transform
Authors: ZHANG Songbai , WU Zaisheng , XIE Ming , SHEN Guoli , YU Ruqin 
Published: April 2009

AbstractA new strategy for homogeneous detection of DNA hybridization in single‐step format was developed based on fluorescence quenching by gold nanoparticles. The gold nanoparticle is functionalized with 5′‐thiolated 48‐base oligonucleotide (probe sequence), whose 3′‐terminus is labeled with fluorescein (FAM), a negatively charged fluorescence dye. The oligonucleotide adopts an extended configuration due to the electrostatic repulsion between negatively charged gold nanoparticle and the FAM‐attached probe sequence. After addition of the complementary target sequence, specific DNA hybridization induces a conformation change of the probe from an extended structure to an arch‐like configuration, which brings the fluorophore and the gold nanoparticle in close proximity. The fluorescence is efficiently quenched by gold nanoparticles. The fluorescence quenching efficiency is related to the target concentration, which allows the quantitative detection for target sequence in a sample. A linear detection range from 1.6 to 209.4 nmol/L was obtained under the optimized experimental conditions with a detection limit of 0.1 nmol/L. In the assay system, the gold nanoparticles act as both nanoscaffolds and nanoquenchers. Furthermore, the proposed strategy, in which only two DNA sequences are involved, is not only different from the traditional molecular beacons or reverse molecular beacons but also different from the commonly used sandwich hybridization methods. In addition, the DNA hybridization detection was achieved in homogenous solution in a single‐step format, which allows real‐time detection and quantification with other advantages such as easy operation and elimination of washing steps.
Identification of Phenylethanoid Glycosides in Plant Extract of Plantago asiatica L. by Liquid Chromatography‐Electrospray Ionization Mass Spectrometry
Authors: LI Li , LIU Chunming , LIU Zhiqiang , TSAO Rong , LIU Shuying 
Published: April 2009

AbstractThe present work describes a liquid chromatography‐electrospray ionization mass spectrometry (LC‐ESI‐MS) method for rapid identification of phenylethanoid glycosides in plant extract from Plantago asiatica L. By using a binary mobile phase system consisting of 0.2% acetic acid and acetonitrile under gradient conditions, a good separation was achieved on a reversed‐phase C18 column. The [M–H]− ions, the molecular weights, and the fragment ions of phenylethanoid glycosides were obtained in the negative ion mode using LC‐ESI‐MS. The identification of the phenylethanoid glycosides (peaks 1–3) in the extract of P. asiatica L. was based on matching their retention time, the detection of molecular ions, and the fragment ions obtained by collision‐induced dissociation (CID) experiments with those of the authentic standards and data reported in the literature.
Synthesis and Antiviral Activities of Chiral Thiourea Derivatives
Authors: YAN Zhikun , CAI Xuejian , YANG Xuan , SONG Baoan , CHEN Zhuo , BHADURY S. Pinaki , HU Deyu , JIN Linhong , XUE Wei , LU Ping 
Published: April 2009

AbstractAn environmentally benign method has been developed for the synthesis of novel chiral thiourea derivatives in high yields in ionic liquid [Bmim]PF6. The ionic solvent can be recovered and reused without any loss of its activity. The target compounds were characterized by elemental analysis, IR, 1H NMR and 13C NMR spectral data. According to the preliminary bioassay, some of the chiral thiourea analogues exhibited moderate in vivo antiviral activities against TMV at a concentration of 500 mg/L. Title chiral compound 3i was found to possess good in vivo protection, inactivation and curative activities of 57.0%, 96.4% and 55.0%, respectively against TMV with an inhibitory concentration at 500 mg/L. The title chiral compound 3i revealed better inactivation effect on TMV (EC50=50.8 µg/mL) than Ningnanmycin (EC50=60.2 µg/mL).
Synthetic Multimeric Heptyl Mannosides as Potent Antiadhesives of Uropathogenic Escherichia coli
Authors: Gouin Sébastien G. , Wellens Adinda , Bouckaert Julie , Kovensky José 
Published: April 2009

AbstractSweet medicine: Multimeric glycoconjugates with valencies ranging from one to four were synthesized by click chemistry. Unprecedented adhesion inhibitions of piliated E. coli to human bladder cells were recorded with the multimers; a tetravalent derivative showed inhibitory concentrations 6000‐ and 64‐fold lower than mannose and heptyl α‐D‐mannoside, respectively.magnified imageUrinary tract infections caused by uropathogenic Escherichia coli presents a serious communal and nosocomial health problem initiated by bacterial adhesion to the bladder cells. E. coli expresses fimbriae with a mannose‐binding adhesin, FimH, at the tip. Heptyl α‐D‐mannoside (HM) is a nanomolar inhibitor of this lectin, preventing adhesion of type 1‐piliated E. coli and reducing bacteria levels in a murine cystitis model. Herein, we described the synthesis of multimeric heptyl‐mannosides with valencies ranging from one to four by copper‐catalyzed azide alkyne cycloaddition (CuAAC). Biological evaluation of the multivalent compounds revealed an increase in potency compared to HM. Inhibition of bladder cell binding highlighted a promising tetravalent derivative with inhibitory concentrations 6000‐ and 64‐fold lower than mannose and HM respectively.