bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and properties of hydrogels of poly(acrylic‐co‐acroloyl β‐cyclodextrin)
Authors: Huang Yi , Fan Xiao‐Dong 
Published: May 2009

AbstractNovel acrylic monomers (β‐CD‐A and β‐CD‐6‐EA) containing β‐cyclodextrin (β‐CD) with different extent of substitution were prepared by using dicyclohexylcarbodiimide (DCC) as a condensation agent at room temperature. Two kinds of functional hydrogels were also synthesized by copolymerization of β‐CD‐A and β‐CD‐6‐EA with acrylic acid (AAc) using a redox initiator system in aqueous solution. The nuclear magnetic resonance (1H NMR), infrared spectroscopy (IR), thermogravimetric analysis (TGA) were employed to character the molecular structures of β‐CD modified monomers and their copolymers. The swelling experiments indicate that the hydrogels with different equilibrium swelling ratio (ESR) possess obvious pH‐sensitivity and distinct dynamic swelling behavior. Using an anti‐cancer drug, chlorambucil (CHL), able to form complexes with β‐CD in water, as a model compound, the controlled drug release behaviors of these hydrogels were investigated. The release behavior of CHL from two kinds of hydrogels synthesized reveals that the release rate of CHL can be effectively controlled by pH values, cross‐linking density, and β‐CD content. In addition, it is found that the β‐CD with the proper frame and concentration can increase release efficiency of CHL from the hydrogels. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and investigation of ethylene–vinyl acetate copolymer/silicone rubber/clay nanocomposites
Authors: Fang Shoulin , Hu Yuan , Song Lei , Wu Jing 
Published: May 2009

AbstractIn this article, the combination of silicone rubber (SR) elastomer with synthetic iron montmorillonite (Fe‐MMT) to form a kind of new flame‐retardant system based on an ethylene–vinyl acetate (EVA) copolymer is first reported. Also, the flame retardancy of the EVA/SR/Fe‐MMT hybrid are compared with that of EVA/SR/natural sodium montmorillonite. The structures of the nanocomposites were characterized with X‐ray diffraction and transmission electron microscopy. Cone calorimeter tests and thermogravimetric analysis were used to evaluate the flame‐retardant properties and thermal stability of the composites, respectively. In addition, tensile tests were carried out with a universal testing machine, and the morphology of the fracture surface was observed with environmental scanning electron microscopy. We found that SR/organophilic montmorillonite (Fe‐OMT) was more effective in reducing the primary peak heat release rate of the nanocomposite, and the EVA/SR/Fe‐OMT hybrid had a higher thermal stability in the deacetylated polymer than EVA/SR/sodium organophilic montmorillonite. Moreover, the exfoliated EVA/SR/Fe‐OMT nanocomposite displayed excellent mechanical properties because of a better dispersion of Fe‐OMT in the polymer matrix, and a possible mechanism is discussed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of intercalated lamellar hydroxyapatite/gelatin nanocomposite for bone substitute application
Authors: Zuo Guifu , Liu Chao , Luo Honglin , He Fang , Liang Hui , Wang Jiehua , Wan Yizao 
Published: May 2009

AbstractHydroxyapatite (HAp)/polymer composites have been widely investigated for bone substitute applications in recent years. Inspired by the arrangement of ordered organic and inorganic layers in natural bones and seashells, for the first time a novel intercalated nanocomposite of gelatin and lamellar HAp was prepared via solution intercalation process. X‐ray diffraction (XRD) results showed that the basal spacing of HAp lamellas enlarged by 3.0 nm from 3.1 nm to 6.1 nm, indicating that the gelatin molecules had been intercalated into the gallery of lamellar HAp. The microstructures of pure lamellar HAp and intercalated gelatin/HAp nanocomposite were observed by transmission electron microscopy (TEM) analysis. Fourier transform infrared spectroscopy (FT‐IR) analysis revealed that there were chemical interactions between gelatin molecules and HAp. Thermogravimetric analysis (TGA) results confirmed that thermal stability of the composites was enhanced. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Morphology, rheological behavior, and thermal stability of PLA/PBSA/POSS composites
Authors: Wang Ruyin , Wang Shifeng , Zhang Yong 
Published: May 2009

AbstractOctavinyl POSS (vPOSS) and epoxycyclohexyl POSS (ePOSS) were separately incorporated into the poly(lactic acid)/poly(butylene succinate‐co‐adipate) (PLA/PBSA) blend by melt mixing. Field emission scanning electron microscopy and X‐ray diffraction analysis revealed that vPOSS existed as crystalline aggregates, whereas ePOSS was more uniformly dispersed in the composites. The storage modulus and complex viscosity slightly decreased after the addition of vPOSS, but significantly increased after the addition of ePOSS, indicating the higher melt elasicity and broader processing window of the PLA/PBSA after the addition of ePOSS. The chloroform solutions of PLA/PBSA/ePOSS composites were turbid in appearance, and the extracted POSS showed absorbant peaks assigned to the vibration of OH and CO groups in the Fourier transform infrared spectroscopy analysis, indicating the reactions between ePOSS and the PLA/PBSA. Polarized optical microscopy analysis revealed that the two types of POSS could act as nucleating agents for PLA, and enhance its crystallization ability. Thermal gravimetric analysis showed that the addition of the two types of POSS increased the decomposition temperature and activation energy, consequently retarding the thermal degradation of PLA/PBSA. The retardation of degradation is more significant with the addition of ePOSS, for the reactions reduced the end groups of PLA/PBSA as well as the molecular chain mobility. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci 2009
Preparation of a silica/poly(n‐butyl acrylate‐co‐acrylic acid) composite latex and its pressure‐sensitive properties
Authors: Wang Nongyue , Guo Yakun , Xu Hongping , Liu Xinran , Zhang Liqun , Qu Xiongwei , Zhang Liucheng 
Published: May 2009

AbstractSilica with an average particle size of 125 nm was prepared by the sol–gel reaction of tetraethoxysilane with a base catalyst and then modified with a vinyl‐functionalized silane [γ‐methacryloxypropyl trimethoxysilane (MPS)]. The composite latex, with the modified silica as the core and poly(n‐butyl acrylate‐co‐acrylic acid) [poly(BA‐co‐AA)] polymer as the shell, was synthesized by a semicontinuous emulsion polymerization and used as a pressure‐sensitive adhesive. The structures were characterized by Fourier transform infrared spectrometry, X‐ray photoelectron spectroscopy, elemental analysis, and transmission electron microscopy. The particle sizes of the silica and MPS‐modified silica (MPS–silica)/poly(BA‐co‐AA) composite latexes were determined by dynamic light scattering in a semicontinuous emulsion polymerization online. The monomers of n‐butyl acrylate and acrylic acid grew around the MPS–silica particles without significant secondary nucleation, and the composite latexes exhibited a core–shell structure with the modified silica particles enwrapped in poly(BA‐co‐AA). To compare the adhesion properties, including the loop tack force, peel strength, and shear resistance, by Fédération Internationale des Fabricants et Transformateurs d'Adhésifs et Thermocollants sur Papiers et Autres Supports test methods, poly(methyl methacrylate‐co‐allyl methacrylate)/poly(BA‐co‐AA) latex and the full poly(BA‐co‐AA) latex were prepared with the same particle size and the same emulsion polymerization process. The shear resistance of the composite latex film greatly increased after the addition of the silica to the core of the poly(BA‐co‐AA) latex. The relationships between the adhesive properties and the different structures in the core components were examined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
N‐(Indazolyl)benzamido Derivatives as CDK1 Inhibitors: Design, Synthesis, Biological Activity, and Molecular Docking Studies
Authors: Raffa Demetrio , Maggio Benedetta , Cascioferro Stella , Raimondi Maria Valeria , Daidone Giuseppe , Plescia Salvatore , Schillaci Domenico , Cusimano Maria Grazia , Titone Lucina , Colomba Claudia , Tolomeo Manlio 
Published: May 2009

AbstractA series of N‐1H‐indazole‐1‐carboxamides has been synthesized and their effects on both CDK1 / cyclin B and the K‐562 (human chronic myelogenus leukemia) cell line were evaluated. Using a computational model, we have observed that all the most active compounds 9e, f, i–n exhibited the same binding mode of purvanalol A in the ATP‐binding cleft. Although they were able to moderately inhibit the leukemic cell line K‐562 and to show inhibitory activity against the Cdc2‐Cyclin B kinase in the low micromolar range, they turned out to be non‐cytotoxic against HuDe (IZSL) primary cell cultures from human derm. These preliminary results are quite encouraging in view of the low toxicity demonstrated by the above‐mentioned compounds.
Synthesis and Biological Activities of 2,4‐Diaminopteridine Derivatives
Authors: Ma Fei , Lü Gang , Zhou Wei‐Fen , Wang Qiu‐Juan , Zhang Yi‐Hua , Yao Qi‐Zheng 
Published: May 2009

AbstractSubstituted 2,4‐diaminopteridine derivatives10a–10lwere prepared in moderate to good yield. Their structures were confirmed by1H‐NMR and MS spectroscopy, as well as by elemental analysis. Their inhibitory properties against inducible nitric oxide synthase (iNOS) were evaluatedin vitro. Biological tests indicated that compound10a,10d,10e,10h,10i, and10lshowed potent inhibitory activities similar to that of methotrexate (MTX), while the activities of compound10b,10c,10f,10g,10j, and10kare stronger than MTX. Two compounds, i. e.,10b(IC50= 18.85 μM) and10i(IC50= 24.08 μM) were further studied for their effect on septic shock in rats and immunologically liver injured mice (in vivo). The results demonstrated that10band10ihad the capacity to increase the blood pressure in septic shock and showed notable protective activities on immunological hepatic injury.
1 D Tubular and 2 D Metal–Organic Frameworks Based on a Flexible Amino Acid Derived Organic Spacer
Authors: Rebilly Jean‐Noël , Bacsa John , Rosseinsky Matthew J. 
Published: May 2009

AbstractFlexible, yet rigid! A ligand derived from glutamic acid generates chiral MOF architectures ranging from 1D to 2D that are organized in the crystal through a complex hierarchy of coordination and hydrogen bonds that include encapsulation of solvent molecules. The flexibility of the ligand backbone gives access to several topologies and dimensionalities depending on the type of metal center used in the synthesis.magnified imageThe organic ligand bgxH4, resulting from the condensation of two glutamate moieties on a xylene core, has been designed to generate chiral metal–organic frameworks with increased metal–metal distances in order to favor their potential porosity. The in situ reactivity of the ligand, through cyclization, led to the bpgxH2 ligand, which displays an extremely rich architectural potential. Under formate‐generating conditions, two 1D tubular and one 2D MOFs based on bpgxH2 have been obtained, incorporating up to three different organic linkers, and organized in an exquisite hierarchical way by the combined effects of the flexibility, the coordinating groups, and the H‐bonding groups of the ligand. Furthermore, the tubular structures display pockets where water molecules are encapsulated.
Finite time agreement protocol design of multi‐agent systems with communication delays
Authors: Wang Li , Chen Zengqiang , Liu Zhongxin , Yuan Zhuzhi 
Published: May 2009

AbstractIn this paper, the finite‐time agreement problem of continuous‐time multi‐agent systems with communication delays is considered. First, the multi‐agent system researched in the paper is described. Second, some notations and lemmas used in the paper are given. Then, agreement protocols for continuous (but non‐smooth) multi‐agent systems are proposed, which ensure that the states of agents reach agreement in finite time. The stability analysis and simulations are presented to show the effectiveness of the method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Simultaneous stabilization for a collection of nonlinear control systems in canonical form
Authors: Wu Jenq‐Lang 
Published: May 2009

AbstractA controller design method is provided to simultaneously stabilize a collection of nonlinear control systems in canonical form. It is shown that, under a mild assumption, any collection of nonlinear systems in canonical form can be simultaneously stabilized by one continuous state feedback controller. A constructive universal formula is presented explicitly. An illustrative example is given to demonstrate the validity of the method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Fuzzy multipath filter with Kalman algorithm for tracking a low‐altitude target
Authors: Chen Yee Ming , Wang Wen‐Shiang 
Published: May 2009

AbstractTo process tracking low‐altitude targets with multipath propagation is a difficult task. The difficulty is derived from a large number of uncertain knowledge (parameters) such as the radar waveform frequency, the specific signal processing, the surface reflectivity, the actual target elevation and range, etc. This paper offers a technique based on fuzzy logic to solve the uncertain measurement error by multipath propagation. Also, we apply quantitative analysis presenting the degree of multipath effect required to achieve the aforementioned goal. Meanwhile, tracking filter estimation is used to reduce the measurement error by the multipath propagation. After the simulation, the fuzzy‐logic‐based technique not only can simplify the process of the model building by the interacting multiple model but also can promote the tracking accuracy. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Delay‐dependent robust stability and stabilization for uncertain discrete singular systems with delays
Authors: Ma Shuping , Zhang Chenghui , Cheng Zhaolin 
Published: May 2009

AbstractThe robust stability and robust stabilization for time‐delay discrete singular systems with parameter uncertainties is discussed. A delay‐dependent linear matrix inequality (LMI) condition for the time‐delay discrete systems to be nonsingular and stable is given. Based on this condition and the restricted system equivalent transformation, the delay‐dependent LMI condition is proposed for the time‐delay discrete singular systems to be admissible. With this condition, the problems of robust stability and robust stabilization are solved, and the delay‐dependent LMI conditions are obtained. Numerical examples illustrate the effectiveness of the method given in the paper. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Observer‐based non‐fragile control against measurement disturbances and controller perturbations for discrete systems with state delay
Authors: Fang Xiaosheng , Wang Jingcheng 
Published: May 2009

AbstractThis paper investigates the observer‐based non‐fragile control problem for a class of discrete time delay systems with measurement disturbances and controller perturbations. A simultaneous state and disturbance estimation technique is developed by designing a state observer for a descriptor system obtained from the original system. Based on this observer, the design method of a non‐fragile controller is then formulated and the controller design problem is transformed to a convex optimization problem, which can be solved by a linear matrix inequality approach. In this design, the additive and multiplicative forms of uncertainties which perturb the gains of control and observer are both considered. The resultant non‐fragile observer‐based controller guarantees that the closed‐loop system is asymptotically stable and can tolerate measurement disturbances and a certain degree of controller parameter perturbation. A numerical example is given to illustrate the effectiveness of the proposed design method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Optimal disturbance rejection control for singularly perturbed composite systems with time‐delay
Authors: Zhang Bao‐Lin , Tang Gong‐You , Yue Dong 
Published: May 2009

AbstractThe optimal control problem for a class of singularly perturbed time‐delay composite systems affected by external disturbances is investigated. The system is decomposed into a fast linear subsystem and a slow time‐delay subsystem with disturbances. For the slow subsystem, the feedforward compensation technique is proposed to reject the disturbances, and the successive approximation approach (SAA) is applied to decompose it into decoupled subsystems and solve the two‐point boundary value (TPBV) problem. By combining with the optimal control law of the fast subsystem, the feedforward and feedback composite control (FFCC) law of the original composite system is obtained. The FFCC law consists of analytic state feedback and feedforward terms and a compensation term which is the limit of the adjoint vector sequence. The compensation term can be obtained from an iteration formula of adjoint vectors. Simulation results are employed to test the validity of the proposed design algorithm. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Transposable elements: powerful facilitators of evolution
Authors: Oliver Keith R. , Greene Wayne K. 
Published: May 2009

AbstractTransposable elements (TEs) are powerful facilitators of genome evolution, and hence of phenotypic diversity as they can cause genetic changes of great magnitude and variety. TEs are ubiquitous and extremely ancient, and although harmful to some individuals, they can be very beneficial to lineages. TEs can build, sculpt, and reformat genomes by both active and passive means. Lineages with active TEs or with abundant homogeneous inactive populations of TEs that can act passively by causing ectopic recombination are potentially fecund, adaptable, and taxonate readily. Conversely, taxa deficient in TEs or possessing heterogeneous populations of inactive TEs may be well adapted in their niche, but tend to prolonged stasis and may risk extinction by lacking the capacity to adapt to change, or diversify. Because of recurring intermittent waves of TE infestation, available data indicate a compatibility with punctuated equilibrium, in keeping with widely accepted interpretations of evidence from the fossil record. We propose a general and holistic synthesis on how the presence of TEs within genomes makes them flexible and dynamic, so that genomes themselves are powerful facilitators of their own evolution
The function of vascular endothelial growth factor
Authors: Nieves Bonnie J. , D'Amore Patricia A. , Bryan Brad A. 
Published: May 2009

AbstractVascular endothelial growth factor (VEGF) is considered the master regulator of angiogenesis during growth and development, as well as in disease states such as cancer, diabetes, and macular degeneration. This review details our current understanding of VEGF signaling and discusses the benefits and unexpected side effects of promising anti‐angiogenic therapeutics that are currently being used to inhibit neovacularization in tumors. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
Functional Analysis of MycE and MycF, Two O‐Methyltransferases Involved in the Biosynthesis of Mycinamicin Macrolide Antibiotics
Authors: Li Shengying , Anzai Yojiro , Kinoshita Kenji , Kato Fumio , Sherman David H. 
Published: May 2009

AbstractMg motors: We characterized the in vitro function of MycE and MycF, two O‐methyltransferases involved in the biosynthesis of mycinamicin antibiotics. Each enzyme was confirmed to be an S‐adenosyl‐L‐methionine (SAM)‐dependent deoxysugar methyltransferase. Their optimal activities require the presence of Mg2+. With the reconstituted in vitro assays, the order of mycinamicin VI→III→IV in the post‐PKS (polyketide synthase) tailoring pathway of mycinamicin was unambiguously determined.magnified image
Position‐Dependent Electrostatic Protection against Protein Aggregation
Authors: Buell Alexander K. , Tartaglia Gian Gaetano , Birkett Neil R. , Waudby Christopher A. , Vendruscolo Michele , Salvatella Xavier , Welland Mark E. , Dobson Christopher M. , Knowles Tuomas P. J. 
Published: May 2009

AbstractProteins with a high propensity to aggregate can be largely prevented from doing so with surprisingly small changes to their primary structure. By using a combination of rational design and quantitative measurements of aggregation rates, we show that adding a single charge in specific “gatekeeper” regions is sufficient to change the timescale for amyloid fibril growth from minutes to weeks, thereby dramatically reducing the efficiency of this process.magnified image
Cover Picture: Thiophene–Diazine Molecular Semiconductors: Synthesis, Structural, Electrochemical, Optical, and Electronic Structural Properties; Implementation in Organic Field‐Effect Transistors (Chem. Eur. J. 20/2009)
Authors: Ortiz Rocío Ponce , Casado Juan , Hernández Víctor , Navarrete Juan T. López , Letizia Joseph A. , Ratner Mark A. , Facchetti Antonio , Marks Tobin J. 
Published: May 2009

AbstractMolecular semiconductors in the guise of three diazine‐functionalized oligothiophenes have been synthesized and their structural, optical, vibrational, electrochemical, and semiconductor properties studied. In their Full Paper on page 5023 ff., J. T. López Navarrete, A. Facchetti, T. J. Marks et al. describe how these diazine‐functionalized oligothiophenes are reasonably efficient hole transporters.magnified image
Energieeffizient und emissionsneutral: Wasserstoff und Brennstoffzelle in der Marktvorbereitung
Authors: Bonhoff K. 
Published: May 2009

AbstractWasserstoff als Kraftstoff und die Brennstoffzelle als hocheffiziente und emissionsarme Antriebstechnologie können in Zukunft einen wertvollen Beitrag zur Schonung der Umwelt und zur Schaffung zukunftsfähiger Arbeitsplätze in Deutschland leisten. Deutschlands gute Startposition muss jetzt genutzt werden, um einen wirklichen Markt‐ und Standortvorteil zu erzielen. Der Beitrag gibt einen kurzen Überblick über Initiativen der Bundesrepublik.
Perspektiven für den Ausbau der Wasserstoffinfrastruktur am Beispiel NRW
Authors: Grube T. , Fischedick M. , Pastowski A. , Stolten D. 
Published: May 2009

AbstractDie Vision einer klimafreundlichen zukünftigen energetischen Nutzung von Wasserstoff ist untrennbar mit dessen Erzeugung auf der Basis von regenerativer Energie verknüpft. Für einen Übergangszeitraum kann der Rückgriff auf anderweitig in Industrieprozessen erzeugten Wasserstoff einschließlich vorhandener Infrastrukturelemente sinnvoll sein. Nordrhein‐Westfalen bietet hierfür mit dem Rhein‐Ruhr‐Raum besonders günstige Voraussetzungen und verfügt über zahlreiche Standorte, die sich für energetische Pioniernutzungen von Wasserstoff anbieten. Der Beitrag verknüpft die Erhebung der verfügbaren Wasserstoffmengen in NRW mit der Modellierung des Aufbaus einer Wasserstoffinfrastruktur in NRW und stellt dabei die besondere Ausgangslage des Bundeslandes heraus.
Das Kompetenz‐Netzwerk Brennstoffzelle und Wasserstoff Nordrhein‐Westfalen
Authors: Ziolek Andreas 
Published: May 2009

AbstractZiel des Kompetenz‐Netzwerk Brennstoffzelle und Wasserstoff Nordrhein‐Westfalen (KNBW NRW) der EnergieAgentur.NRW mit Sitz in Düsseldorf ist die Etablierung eines neuen Wirtschaftszweiges durch die gezielte Markteinführung der Brennstoffzellentechnik sowie von Brennstoffzellensystemkomponenten in dazu geeigneten Pilotmärkten. Begleitet durch eine zielgerichtete Forschung und Entwicklung sowie den nachhaltigen Aufbau einer geeigneten Wasserstoffinfrastruktur sollen schrittweise auch die Massenmärkte im mobilen und stationären Bereich erschlossen werden. Das Netzwerk ist derzeit das größte seiner Art in Europa.