bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparative study on curing characteristics and thermomechanical properties of elastomeric nanocomposites: The effects of eggshell and calcium carbonate nanofillers
Authors: Saeb Mohammad Reza , Ramezani‐Dakhel Hadi , Khonakdar Hossein Ali , Heinrich Gert , Wagenknecht Udo 
Published: May 2012

AbstractAfter‐hatching eggshell (AHES) nanobiofiller and nanocalcium carbonate (nano‐CA) were separately added to various elastomers, such as acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), and natural rubber (NR), in various amounts of 5, 10, and 15 phr. The effect of particle size and dispersion of such nanofillers on thermomechanical properties and curing characteristics were then investigated. The ultimate tensile properties of SBR and NR nanocomposites were improved to some extent when 5 phr of AHES nanofiller was added to the rubber compound compared to CA. In the case of NBR nanocompounds, however, the mechanical properties were seemingly comparable, irrespective of the type of nanofiller. This contradictive behavior could be attributed to the alteration of crosslink density due to particular filler–matrix interaction while using mineral and natural fillers. The results of the rheometric study revealed that using AHES rather than CA slightly increases the scorch time of all types of prepared nanocomposites, whereas a significant drop in the optimum curing time was seen for NBR nanocomposites containing AHES biofiller. Moreover, thermogravimetric analysis showed similar thermal stability for SBR nanocomposites containing AHES and CA fillers. Finer particle size of CA and higher porosity of AHES at high and low loading levels were respectively the main reasons for improvement of ultimate properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Electrospun magnetic carbon composite fibers: Synthesis and electromagnetic wave absorption characteristics
Authors: Yang Ying , Guo Zhen , Zhang Huan , Huang Daqing , Gu Jialin , Huang Zhenghong , Kang Feiyu , Alan Hatton T. , Rutledge Gregory C. 
Published: May 2012

AbstractElectrospun polyacrylonitrile (PAN)‐based carbon composite fibers embedded with magnetic nanoparticles have been developed as materials for electromagnetic wave absorption. The nanocomposite fibers were prepared by electrospinning from a dispersion of magnetite (Fe3O4) nanoparticles stabilized by L‐glutamic acid in a solution of PAN and N, N‐dimethyl formamide. The Fe3O4‐embedded PAN nanofibers were stabilized at 270°C in air and carbonized at 800°C in nitrogen. The Fe3O4 nanoparticles were crystalline with a particle size of about 7 nm, most of which was reduced to Fe3C with agglomerates of up to 50 nm diameter in the carbon fibers. The carbon morphology was mostly disordered, but exhibited a layered graphitic structure in the vicinity of the nanoparticles. The carbon composite fiber exhibited ferromagnetic behavior, and the induced magnetic saturation per unit mass of fibers increased with increasing Fe3O4 content in the precursor. The complex relative dielectric permittivity was tuned by adjusting the amount of Fe3O4 in the carbon fiber precursor. With increasing Fe3O4 content, good electromagnetic wave absorption characteristics were observed below 6 GHz, even for samples with fiber loadings as low as 5 wt %. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Effect of intermolecular and intramolecular forces on hydrodynamic diameters of poly(N‐isopropylacrylamide) copolymers in aqueous solutions
Authors: Yang Lei , Liu Tianqing , Song Kedong , Wu Shuang , Fan Xin 
Published: May 2012

AbstractA novel copolymer, poly(N‐isopropylacrylamide‐co‐hydroxypropyl methacrylate‐co‐3‐trimethoxysilypropyl methacrylate) has been synthesized and the hydrodynamic diameters in various aqueous solutions under different temperatures are determined by dynamic light scattering. The results show that the hydrodynamic diameters of copolymers have no obvious change in each working solution below lower critical solution temperature (LCST); across LCST, the diameters increased suddenly at different initial temperature in various aqueous solutions; above LCST, they decreased slightly as the temperature increased in UHQ water, and increased continuously with increasing temperature or salt concentration in saline solutions, and reduced with the rising of pH value in pH buffer. These are attributed to different intermolecular and intramolecular forces leading to disparity in dimension, conformation, and LCST of copolymers. The hydrogen bonding between water molecules and copolymer chains could maintain size and conformation of copolymer single chain; the hydrogen bonding between amide linkages and hydrophobic interactions between isopropyl groups result in intramolecular collapse and intermolecular aggregation; the electrostatic repulsion weakens aggregation extent of copolymers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Self‐assembly of bovine serum albumin and poly(acrylic acid) induced by noncovalent bonds
Authors: Du Weiping , Wang Yansong 
Published: May 2012

AbstractBovine serum albumin/poly(acrylic acid), BSA/PAA, nano‐scaled particles were produced by noncovalent bonds induced self‐assembly method at acid pH area. Proper conditions during preparation process, such as pH value, BSA/PAA weight ratio(WR), PAA molecular weight, were researched by studying the hydrodynamic diameter, polydispersity index, and ζ potential of the nanoparticles. Complex formation between BSA and PAA was studied by FT‐IR, AFM, and TEM. BSA chains are supposed to be partly trapped in the nanoparticles core after interaction with PAA because of the electrostatic attractions and hydrogen bonds interactions between BSA and PAA, while the rest of the BSA chains should form the shell of the nanoparticles. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Study of viscoelastic properties of nanocomposites of SiO2–acrylonitrile–butadiene–styrene
Authors: Haghtalab Ali , Rahimi Sedighe 
Published: May 2012

AbstractNanocomposites of acrylonitrile–butadiene–styrene (ABS) and nanosilica with different nanoparticle sizes and various loadings are prepared. Rheological experiments such as frequency sweep, strain sweep, and rotational test are performed to investigate the influence of nanoparticle loading and size on the viscoelastic properties of the nanocomposites. The results show that nanocomposites with higher filler loading and smaller particle size have both higher storage and loss moduli. Moreover, the results indicate that the storage modulus is more sensitive than loss modulus to filler loading and nanoparticle size. The smaller nanoparticles and higher filler loadings lead to the enhancement of nanoparticle surface area so that the viscoelastic properties are intensified through increase of polymer chain adsorption on nanoparticle, and creation of a network structure in the nanocomposites. The network structure causes changes to the rheological behavior of the nanocomposite such as solid‐like behavior in the low‐frequency region and reduction of the Newtonian region. The scanning electron microscopy micrographs revealed that the particle aggregates increase with particle size reduction and increasing nanoparticle content. We also used a nonlinear optimization to obtain the parameters of a multimode Maxwell model for low nanofiller content ABS/SiO2 nanocomposites and found the relaxation times of the polymer chains increased with increasing nanoparticle content. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Optical characterization and differential scanning calorimetry studies of carboxymethyl cellulose–nickel chloride composite system
Authors: Abdel‐Rahim Farid M. , Mahmoud K. H. , Aly K. A. 
Published: May 2012

AbstractCarboxymethyl cellulose (CMC) films doped with nickel chloride hexahydrate have been prepared by casting technique. The phase transitions and thermal stability of the prepared samples were investigated by differential scanning calorimetry and thermogravimetry. The optical absorption was recorded at room temperature in the wavelength range of 190–2500 nm. From the absorption edge studies, the values of the Urbach energy (Ee) were found to be 0.58 eV in case of the pure polymer; however, the Urbach energy values were found to be in the range of 0.64–1.0 eV under additional different percentages of nickel chloride. These energy values indicate that the model based on random fluctuations of the internal fields associated with structure disorder is preferable and transitions are made between band tails. Refractive index, complex dielectric constants have also been determined. Color properties of the prepared samples are discussed in the frame work of CIE L*u*v* color space. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Factors affecting the occurrence of smooth‐coated otter in aquatic systems of the Upper Gangetic Plains, India
Authors: Nawab Asghar , Hussain Syed Ainul 
Published: May 2012

ABSTRACTWith the increasing human pressure on wildlife and its habitat, particularly in South and Southeast Asia, the population of the smooth‐coated otter (Lutrogale perspicillata), a key carnivore of freshwater ecosystems, is rapidly declining. Reliable information on its abundance and other factors affecting its occurrence is lacking from many parts of its range, hindering development of conservation measures.In this paper the findings are presented on relative abundance and habitat parameters associated with the occurrence of the smooth‐coated otter in the Corbett Tiger Reserve (CTR), India. Information on habitat structure, spraint (faeces) sites, and otter signs (e.g. footprints, spraints), were recorded in each 500 m section of five rivers in different seasons. The search covered 380, 100 m × 15 m plots laid along the shoreline of the river banks. The importance of different habitat features influencing habitat selection was assessed using an ordination technique.In the CTR, the presence of otters was recorded from the three river systems that were relatively undisturbed and supported potential microhabitats for otters. The relative abundance of otters in the Reserve varied between 0.3 and 0.48 individuals km‐1.Occurrence of otters in the region was governed by the presence of habitat features such as rocky and sandy river stretches with gentle bank‐slopes, bank‐side vegetation serving as escape cover, and slow water current. Relatively narrow rivers with several streams joining the main course and with a large number of fallen dead trees were favoured.The reservoir was an unsuitable habitat for otters owing to its steep bank‐slopes (47.38° ± 1.69°) and deep water (6.99 m ± 30.46 m). Various forms of fishing activities, followed by livestock grazing, removal of sand and boulders from the river and removal of shoreline vegetation adversely affected the presence of otter.Restoration of degraded habitats to meet the requirements of otters is the only option for their long‐term conservation. Existing critical otter habitats should be identified and brought into the protected area network, and the wetlands and river basins forming otter habitat managed at a landscape level. Copyright © 2012 John Wiley & Sons, Ltd.
Aquatic macroinvertebrate biodiversity: patterns and surrogates in mountainous Spanish national parks
Authors: Guareschi S. , Gutiérrez‐Cánovas C. , Picazo F. , Sánchez‐Fernández D. , Abellán P. , Velasco J. , Millán A. 
Published: May 2012

ABSTRACT

In Spain, national parks represent the mainstay of conservation polices and attempt to protect the most representative natural ecosystems. However, studies on the ecology and conservation of aquatic biodiversity within protected areas are still scarce. This study aimed at compiling an inventory of the macroinvertebrate families inhabiting the aquatic ecosystems of each mountainous Spanish national park (Sierra Nevada, Cabañeros, Ordesa, Picos de Europa, Aigüestortes and Monfragüe). The results were used to answer two questions: (i) Which environmental variables are related to macroinvertebrate composition and richness in these protected ecosystems? (ii) Which taxon or group of taxa could act as biodiversity surrogates?
Sampling was carried out in 81 aquatic ecosystems across the six national parks during the summers of 2008–2010.
The national parks with the highest richness were Picos de Europa and Cabañeros. Overall, the six parks incorporated 66.2% of the taxa included in the Iberian checklist. Multivariate techniques showed that maximum altitude and the presence of lotic habitats were the most important variables related to different community compositions. The best richness model included the presence of a lotic habitat, together with the percentage of the catchment area with non‐irrigated agriculture and siliceous geology.
Selecting several diverse lotic and lentic water bodies at different altitudes provides the best way of representing Iberian macroinvertebrate diversity. Coleoptera family richness may be used as a macroinvertebrate biodiversity surrogate in Iberian mountainous protected areas because it displayed the highest correlation with the other taxonomic groups and remaining richness values. Such an indicator could be complemented with the use of Odonata family richness for standing waters.
The adequacy of Coleopera and Odonata as biodiversity surrogates should be tested at a wider geographic scale, and other surrogacy concepts (e.g. community composition) considered for assessing the role of this network in the protection of rare and endemic species. Copyright © 2012 John Wiley & Sons, Ltd.
Maximizing modern distribution of complex anatomical spatial information: 3D reconstruction and rapid prototype production of anatomical corrosion casts of human specimens
Authors: Li Jianyi , Nie Lanying , Li Zeyu , Lin Lijun , Tang Lei , Ouyang Jun 
Published: May 2012

AbstractAnatomical corrosion casts of human specimens are useful teaching aids. However, their use is limited due to ethical dilemmas associated with their production, their lack of perfect reproducibility, and their consumption of original specimens in the process of casting. In this study, new approaches with modern distribution of complex anatomical spatial information were explored to overcome these limitations through the digitalization of anatomical casts of human specimens through three‐dimensional (3D) reconstruction, rapid prototype production, and Web‐based 3D atlas construction. The corrosion cast of a lung, along with its associated arteries, veins, trachea, and bronchial tree was CT‐scanned, and the data was then processed by Mimics software. Data from the lung casts were then reconstructed into 3D models using a hybrid method, utilizing both “image threshold” and “region growing.” The fine structures of the bronchial tree, arterial, and venous network of the lung were clearly displayed and demonstrated their distinct relationships. The multiple divisions of bronchi and bronchopulmonary segments were identified. The 3D models were then uploaded into a rapid prototype 3D printer to physically duplicate the cast. The physically duplicated model of the lung was rescanned by CT and reconstructed to detect its production accuracy. Gross observation and accuracy detection were used to evaluate the duplication and few differences were found. Finally, Virtual Reality Modeling Language (VRML) was used to edit the 3D casting models to construct a Web‐based 3D atlas accessible through Internet Explorer with 3D display and annotation functions. Anat Sci Educ. © 2012 American Association of Anatomists.
Loosely‐guided, self‐directed learning versus strictly‐guided, station‐based learning in gross anatomy laboratory sessions
Authors: Kooloos Jan G.M. , de Waal Malefijt Maarten C. , Ruiter Dirk J. , Vorstenbosch Marc A.T.M. 
Published: May 2012

AbstractAnatomy students studying dissected anatomical specimens were subjected to either a loosely‐guided, self‐directed learning environment or a strictly‐guided, preformatted gross anatomy laboratory session. The current study's guiding questions were: (1) do strictly‐guided gross anatomy laboratory sessions lead to higher learning gains than loosely‐guided experiences? and (2) are there differences in the recall of anatomical knowledge between students who undergo the two types of laboratory sessions after weeks and months? The design was a randomized controlled trial. The participants were 360 second‐year medical students attending a gross anatomy laboratory course on the anatomy of the hand. Half of the students, the experimental group, were subjected without prior warning to station‐based laboratory sessions; the other half, the control group, to loosely‐guided laboratory sessions, which was the course's prevailing educational method at the time. The recall of anatomical knowledge was measured by written reproduction of 12 anatomical names at four points in time: immediately after the laboratory experience, then one week, five weeks, and eight months later. The strictly‐guided group scored higher than the loosely‐guided group at all time‐points. Repeated ANOVA showed no interaction between the results of the two types of laboratory sessions (P = 0.121) and a significant between‐subject effect (P ≤ 0.001). Therefore, levels of anatomical knowledge retrieved were significantly higher for the strictly‐guided group than for the loosely‐guided group at all times. It was concluded that gross anatomy laboratory sessions with strict instructions resulted in the recall of a larger amount of anatomical knowledge, even after eight months. Anat Sci Educ. © 2012 American Association of Anatomists.
Crosstalk between endogenous and synthetic components – synthetic signaling meets endogenous components
Authors: Morey Kevin J. , Antunes Mauricio S. , Barrow Matt J. , Solorzano Fernando A. , Havens Keira L. , Smith J. Jeff , Medford June 
Published: May 2012

AbstractSynthetic biology uses biological components to engineer new functionality in living organisms. We have used the tools of synthetic biology to engineer detector plants that can sense man‐made chemicals, such as the explosive trinitrotoluene, and induce a response detectable by eye or instrumentation. A goal of this type of work is to make the designed system orthogonal, that is, able to function independently of systems in the host. In this review, the design and function of two partially synthetic signaling pathways for use in plants is discussed. We describe observed interactions (crosstalk) with endogenous signaling components. This crosstalk can be beneficial, allowing the creation of hybrid synthetic/endogenous signaling pathways, or detrimental, resulting in system noise and/or false positives. Current approaches in the field of synthetic biology applicable to the design of orthogonal signaling systems, including the design of synthetic components, partially synthetic systems that utilize crosstalk to signal through endogenous components, computational redesign of proteins, and the use of heterologous components, are discussed.
Triple‐negative breast cancer: multipronged approach, single‐arm pilot phase II study
Authors: Recchia Francesco , Candeloro Giampiero , Desideri Giovambattista , Necozione Stefano , Recchia Cornelia O. C. , Cirulli Vincenzo , Rea Silvio 
Published: May 2012

AbstractAnthracyclines (A) and taxanes (T) are standard first‐line chemotherapy agents for patients with advanced breast cancer. Platinum analogues have also shown activity in the triple‐negative breast cancer (TNBC) histology, but clinical data are limited. Here we report the long‐term follow‐up of a phase II study on TNBC treated with a combined modality therapy, including induction with AT, cyclophosphamide, methotrexate, and 5‐fluorouracil (CMF) with concurrent radiation therapy, and a dose‐dense consolidation chemotherapy (HDCT) with carboplatin (CBDCA), ifosfamide (IFX), etoposide (VP‐16). Patients' median age was 44 years, with 73% premenopausal. Epirubicin 75 mg/m2 and docetaxel 75 mg/m2 were administered to 70 patients with TNBC: as neoadjuvant and adjuvant therapy to 12 and 58 patients, respectively. Postoperative radiation therapy, 5000 cGy, was delivered, synchronous with triweekly CMF. After radiation therapy, two courses of HDCT with CBDCA, IFX, VP‐16, were given, with hematological growth factors. After a median follow‐up of 81 months, all patients were evaluable for toxicity and response. Most important toxicity were grade 3 skin reaction and grade 4 hematological in 3% and 31% of patients, respectively. Pathological complete response was observed in 25% of patients receiving preoperative chemotherapy. Treatment failures were as follows: eight visceral, four contralateral breast cancer, four locoregional, and one leukemia. Five‐year progression‐free survival and overall survival rate were 78% and 91%, respectively. Induction chemotherapy, followed by chemoradiation therapy and HDCT, provides a prolonged disease‐free period and a significant increase in overall survival in TNBC, with an acceptable toxicity profile.
ChemInform Abstract: Ni5‐δSn4Zn (δ ≈ 0.25) from Single‐Crystal Data.
Authors: Schmetterer Clemens , Effenberger Herta Silvia , Marker Martin C. J. , Flandorfer Hans 
Published: May 2012

AbstractSingle crystals of the title compound are grown from the elements (alumina crucible, 1453 K).
ChemInform Abstract: Molten Salt Synthesis of a Mixed‐Valent Lanthanide(III/IV) Oxychloride with an Unprecedented Sillen X24 Structure: Ce1.3Nd0.7O3Cl.
Authors: Vigier Jean‐Francois , Renard Catherine , Henry Natacha , Laplace Annabelle , Abraham Francis 
Published: May 2012

AbstractThe new title compound is precipitated under wet argon from NdCl3 and CeCl3 in a molten LiCl/CaCl2 (30:70) mixture (705 °C, 4 h).
ChemInform Abstract: Tri‐Metallic Deltahedral Zintl Ions: Experimental and Theoretical Studies of the Novel Dimer [(Sn6Ge2Bi)2]4‐.
Authors: Gillett‐Kunnath Miriam M. , Munoz‐Castro Alvaro , Sevov Slavi C. 
Published: May 2012

Abstract[K(2,2,2‐crypt)]4 [(Sn6Ge2Bi)2]·1.5en is synthesized either by reacting (Sn9‐xGex)4‐ clusters with BiPh3 or by direct extraction from precursors of nominal composition K4Ge4Sn4Bi.
ChemInform Abstract: Novel Phosphine—Phosphites and Their Use in Asymmetric Hydrogenation.
Authors: Farkas Gergely , Balogh Szabolcs , Szoelloesy Aron , Uerge Laszlo , Darvas Ferenc , Bakos Jozsef 
Published: May 2012

AbstractRhodium complexes derived from axially chiral ligands (I) are efficient catalysts in the asymmetric hydrogenation reactions of dehydroamino acid esters (II) and itaconate (IV), in the latter case even at only 0.01 mol% catalyst loading.
ChemInform Abstract: Two Iron Catalysts Are Better than One: A General and Convenient Reduction of Aromatic and Aliphatic Primary Amides.
Authors: Das Shoubhik , Wendt Bianca , Moeller Konstanze , Junge Kathrin , Beller Matthias 
Published: May 2012

AbstractThe first iron‐based catalytic reduction of primary amides (I) and (III) is presented by using a selective, operational simple, safe and mild protocol.
ChemInform Abstract: Highly Efficient and Convenient Strecker Reaction of Carbonyl Compounds and Amines with TMSCN Catalyzed by MCM‐41 Anchored Sulfonic Acid as a Recoverable Catalyst.
Authors: Dekamin Mohammad G. , Mokhtari Zahra 
Published: May 2012

AbstractA mild, straightforward, and green one‐pot three‐component procedure for the synthesis of α‐aminonitriles is developed.
ChemInform Abstract: A Highly Active and Magnetically Retrievable Nanoferrite—DOPA—Copper Catalyst for the Coupling of Thiophenols with Aryl Halides.
Authors: Baig R. B. Nasir , Varma Rajender S. 
Published: May 2012

AbstractDiaryl sulfides (III) are synthesized using a magnetically recoverable heterogeneous Cu catalyst under microwave irradiation.
ChemInform Abstract: Iron‐Catalyzed Tandem Cross‐Dehydrogenative Coupling (CDC) of Terminal Allylic C(sp3) to C(sp2) of Styrene and Benzoannulation in the Synthesis of Polysubstituted Naphthalenes.
Authors: Liu Hua , Cao Li , Sun Jia , Fossey John S. , Deng Wei‐Ping 
Published: May 2012

AbstractFor the title reaction a high regioselectivity is observed to afford naphthalene derivatives (III), (V) and (VII)/(VIII) rather than cyclopentenes.