bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Photovoltaic Properties of a Poly(2,7‐carbazole) Derivative Based on Dithienosilole and Benzothiadiazole
Authors: Zhou Jiaoyan , Wan Xiangjian , Liu Yongsheng , Wang Fei , Long Guankui , Li Chenxi , Chen Yongsheng 
Published: April 2011

AbstractA low bandgap poly(2,7‐carbazole) derivative PCDSBT containing dithienosilole and benzothiadiazole is synthesized by Stille polymerization. The incorporation of dithienosilole and carbazole causes PCDSBT to have a broad absorption from 350 to 800 nm and a relatively low HOMO level. Solar cell devices fabricated by blending PCDSBT with [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) at a 1:2 weight ratio in a mixed solvent of 3% (by volume), 1,8‐diiodooctane, and 97% dichlorobenzene lead to a power conversion efficiency of 1.65% under the illumination of AM 1.5G (100 mW · cm−2).
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Biomimetic Route to Calcium Phosphate Coated Polymeric Nanoparticles: Influence of Different Functional Groups and pH
Authors: Schöller Katrin , Ethirajan Anitha , Zeller Anke , Landfester Katharina 
Published: April 2011

AbstractThe controlled synthesis of organic–inorganic hybrid particles with selective morphology using polymeric nanoparticles as templates offers an effective biomimetic route to design composite materials with interesting properties for various potential applications. In this study, the formation of hybrid particles via the bio‐inspired mineralization of calcium phosphate (CaP) on the surface of different surface‐functionalized polymeric nanoparticles is reported. The versatile miniemulsion polymerization is used to prepare different surface functionalized nanoparticles with covalently bound carboxylic acid and phosphonic acid surface‐functionalities. Functional comonomers with varying hydrophilicity like acrylic acid (AA), vinylphosphonic acid (VPA), and vinylbenzylphosphonic acid (VBPA) are employed for the copolymerization with styrene. The influence of different functional groups at different pH on the crystal phase and morphology of the calcium phosphate phase in the hybrid nanoparticles is analyzed in detail by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron as well as X‐ray diffraction (ED and XRD) techniques. The calcium ion binding affinity of different surface functional groups at varying loading conditions is studied using calcium ion selective electrode to shed light on the mineralization kinetics as well as on the interfacial chemistry involved between the complexing ions and the functional groups on the particle surface. The CaP/polymer hybrid particles with well‐defined crystal phases and morphologies offering varying surface topographies are interesting candidates for cell adhesion and proliferation studies for potential tissue engineering applications. They could be used as bone fillers, building blocks for the nucleation, and the growth of new bone material or implant coatings to reduce the immune response.
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Coordination Polymer Nanobelts as an Effective Sensing Platform for Fluorescence‐enhanced Nucleic Acid Detection
Authors: Li Hailong , Wang Lei , Zhai Junfeng , Zhang Yingwei , Tian Jingqi , Sun Xuping 
Published: April 2011

AbstractIn this communication, the application of coordination polymer nanobelts (CPNs) assembled from H2PtCl6 and 3,3′,5,5′‐tetramethylbenzidine (TMB) are explored as an effective fluorescent sensing platform for nucleic acid detection for the first time. The suggested method has a high selectivity down to single‐base mismatch. DNA detection is accomplished by the following two steps: (1) CPN binds fluorecent dye‐labeled single‐stranded DNA (ssDNA) probe via both electrostatic attraction and π‐π stacking interactions between unpaired DNA bases and CPN. As a result, the fluorescent dye is brought into close proximity to CPN and substantial fluorescence quenching occurs due to photoinduced electron transfer from the nitrogen atom in CPN to the excited fluorophore. (2) The hybridization of adsorbed ssDNA probe with its target generates a double stranded DNA (dsDNA). The duplex cannot be adsorbed by CPN due to its rigid conformation and the absence of unpaired DNA bases, leading to an obvious fluorescence enhancement.
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The Consumption of Oxygen and p‐Methoxyphenol in Acrylic Acid – Kinetics and Modeling
Authors: Brand Raphael H. , Hartwig A. , Opitz B. , Pfeifer C. , Drochner A. , Vogel G. Herbert 
Published: April 2011

AbstractFor a safe storage and handling of acrylic acid (AA), a lot of knowledge is necessary. In the present work, investigations were made in order to describe the stabilization processes during the inhibition period (IP) of AA more exactly. The oxygen and p‐methoxyphenol consumption was determined for AA at 70 and 80 °C in an enhanced parameter range and simulated with a kinetic model, using the software Presto Kinetics (R). In the simulation accelerated stabilizer consumptions at 80 °C could be confirmed. The known stabilization mechanism must be enhanced with autocatalytic steps, which lead to an accelerated stabilizer consumption. Furthermore, the stability of AA was examined as a function of the dissolved oxygen mass fraction and the temperature in isoperibolic reactors. The IP follows an Arrhenius behavior; therefore, an extrapolation from higher reaction temperatures to storage conditions is possible. These measurements also confirm the nonlinear stabilizer consumption during the IP at temperatures over 75 °C.
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Semibatch Aqueous‐Solution Polymerization of Acrylic Acid: Simultaneous Control of Molar Masses and Reaction Temperature
Authors: Minari Roque J. , Caceres Gerardo , Mandelli Paola , Yossen Mariana M. , Gonzalez‐Sierra Manuel , Vega Jorge R. , Gugliotta Luis M. 
Published: April 2011

AbstractThe semibatch polymerization of non‐ionized acrylic acid (AA) was investigated with the aim of producing poly(acrylic acid) (PAA) of controlled molar masses, at complete AA conversion, and under safe conditions. The proposed strategy mainly consists in feeding the AA at a constant rate along the reaction, for simultaneously controlling polymerization rate and molar masses. PAA of intermediate ${\bar {M}}_{{\rm n}} $, in the range 1 × 104–2 × 105 g · mol−1, was produced through an adequate selection of both the initiator concentration and the AA flow rate. In all experimental conditions, backbiting reactions were confirmed by 13C NMR. A simple mathematical model was developed to help interpret the experimental results.
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Catalytic Degradation of Polystyrene: Modeling of Molecular Weight Distribution
Authors: Gianoglio Pantano Ioana A. , Asteasuain Mariano , Díaz Mónica F. , Sarmoria Claudia , Brandolin Adriana 
Published: April 2011

AbstractTwo of the most abundant polymers in household waste streams, PS and PE, may be recycled by compatibilization through a Friedel‐Crafts alkylation. This reaction produces a graft copolymer PE‐g‐PS that improves the properties of the blend, but simultaneously degrades PS chains. Since the copolymer efficiency as a compatibilizer depends both on the molecular weight and MWD of its two blocks, the operating conditions for the copolymer synthesis must be carefully tuned. To aid in this task, we present a preliminary mathematical model that focuses on the effect of the catalyst and cocatalyst of the Friedel‐Crafts alkylation on the MWD of the PS chains. The model's predictions are shown to agree with experimental data.
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Topical naphazoline in the treatment of myasthenic blepharoptosis
Authors: Nagane Yuriko , Utsugisawa Kimiaki , Suzuki Shigeaki , Masuda Masayuki , Shimizu Yuko , Utsumi Hiroya , Uchiyama Shinichiro , Suzuki Norihiro 
Published: April 2011

AbstractIntroduction. When treating ocular myasthenia gravis (MG), the risk/benefit profile of corticosteroids is unclear, and acetylcholinesterase inhibitors are not very effective. We examined the efficacy of topical naphazoline in the treatment of myasthenic blepharoptosis. Methods. Sixty MG patients with blepharoptosis (32 with ocular symptoms only and 28 with mild generalized symptoms) were enrolled in a multicenter open trial of topical naphazoline. The effects were reported by patients via a questionnaire and were also confirmed for each patient at the clinic. Results. Among 70 eyes of 60 patients, 20 eyes (28.6%) of 17 patients (28.3%) exhibited a marked response (full eye opening), and 24 eyes (34.3%) of 20 patients (33.3%) showed a good response (adequate but incomplete eye opening). Topical naphazoline was evaluated as useful in the treatment of myasthenic blepharoptosis by >70% of the patients. Conclusions. Topical naphazoline was found to be an effective supplementary symptomatic treatment for myasthenic blepharoptosis. Muscle Nerve 44: 41–44, 2011.
Remote Hydrogen Microwave Plasma Chemical Vapor Deposition of Amorphous Silicon Carbonitride (a‐SiCN) Coatings Derived From Tris(dimethylamino)Silane
Authors: Wrobel Aleksander M. , Blaszczyk‐Lezak Iwona , Uznanski Pawel , Glebocki Bartosz 
Published: April 2011

AbstractAmorphous silicon carbonitride films were produced by remote hydrogen plasma CVD (RP‐CVD) from Tris(dimethylamino)silane precursor. The effect of substrate temperature (TS) on the kinetics of RP‐CVD, chemical composition, structure, surface morphology, and properties of resulting films is reported. The TS dependence of film growth rate imply that RP‐CVD is an adsorption‐controlled process. The increase of TS from 30 to 400 °C causes the elimination of organic moieties from the film and the formation of SiC and SiN network structure. The structure–property relationships were determined. The films deposited at TS = 300 °C appear to be dense materials exhibiting very small surface roughness, high hardness, and an extremely low friction coefficient. They seem to be suitable protective coatings for metal surfaces to increase their wear strength.
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Fast approximations of the rotational diffusion tensor and their application to structural assembly of molecular complexes
Authors: Berlin Konstantin , O'Leary Dianne P. , Fushman David 
Published: April 2011

AbstractWe present and evaluate a rigid‐body, deterministic, molecular docking method, called ELMDOCK, that relies solely on the three‐dimensional structure of the individual components and the overall rotational diffusion tensor of the complex, obtained from nuclear spin‐relaxation measurements. We also introduce a docking method, called ELMPATIDOCK, derived from ELMDOCK and based on the new concept of combining the shape‐related restraints from rotational diffusion with those from residual dipolar couplings, along with ambiguous contact/interface‐related restraints obtained from chemical shift perturbations. ELMDOCK and ELMPATIDOCK use two novel approximations of the molecular rotational diffusion tensor that allow computationally efficient docking. We show that these approximations are accurate enough to properly dock the two components of a complex without the need to recompute the diffusion tensor at each iteration step. We analyze the accuracy, robustness, and efficiency of these methods using synthetic relaxation data for a large variety of protein‐protein complexes. We also test our method on three protein systems for which the structure of the complex and experimental relaxation data are available, and analyze the effect of flexible unstructured tails on the outcome of docking. Additionally, we describe a method for integrating the new approximation methods into the existing docking approaches that use the rotational diffusion tensor as a restraint. The results show that the proposed docking method is robust against experimental errors in the relaxation data or structural rearrangements upon complex formation and is computationally more efficient than current methods. The developed approximations are accurate enough to be used in structure refinement protocols. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Synthesis, characterization, and optical properties of Ag2Mo2O7 nanowires
Authors: Hashim Muhammad , Hu Chenguo , Chen Yanxue , Zhang Cuiling , Xi Yi , Xu Jing 
Published: April 2011

AbstractAg2Mo2O7 nanowires were synthesized by facile hydrothermal method from sodium molybdate and silver nitrate at temperature of 150 °C without any surfactant or template. The synthesized product was characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and transmission electron microscopy (TEM). It was found that the product is of anorthic phase and single crystalline nanowires with width of 200 nm and length up to 100 µm. UV–Visible reflection spectrum demonstrated a band gap of 2.94 eV. Photoluminescence (PL) spectrum exhibited strong violet emission centered at 412 nm and red emission ranging from 600 to 700 nm at room temperature. The greatly enhanced red emission was observed at low temperature. The emission mechanism has been discussed according to the calculated results of electron density of states (DOSs) for Ag2Mo2O7 with consideration of oxygen vacancies by using the Vienna ab initio simulation package (VASP).
XPS analysis and valence band structure of a low‐dimensional SiO2/Si system after Si+ ion implantation
Authors: Zatsepin D. A. , Mack P. , Wright A. E. , Schmidt B. , Fitting H.‐J. 
Published: April 2011

AbstractA X‐ray photoelectron spectroscopy (XPS) of valence band (VB) and core levels are performed for a SiO2/p‐Si heterostructure containing a thin oxide layer of d = 20 nm thickness and implanted by Si+ ions. With an implantation energy of 12 keV the maximum density of the implanted Si+ profile is located close to the SiO2–Si interface at a depth of 18 nm, but a piling‐up of Si is also found immediately beneath the surface up to 2 nm, i.e., within the escape depth of XPS electrons. Thus we may expect a partial phase separation associated with Si aggregation and nanocluster formation imbedded in a non‐stoichiometric SiOx matrix. By means of XPS and in comparison to X‐ray emission spectroscopy (XES) the related changes of the VB structure are investigated.
Silane grafting of TiO2 nanoparticles: dispersibility and photoactivity in aqueous solutions
Authors: Pazokifard Sh. , Mirabedini S. M. , Esfandeh M. , Mohseni M. , Ranjbar Z. 
Published: April 2011

AbstractTitania nano‐sized particles were treated by various amounts of tetraethyl orthosilicate precursor. The extent of grafting was characterized using Fourier transform infrared (FTIR) and ultraviolet‐visible (UV‐Vis) spectroscopy techniques, thermal gravimetric analysis, X‐ray fluorescence and zeta potential measurements. Sedimentation behaviour of titanium dioxide (TiO2) nanoparticles in aqueous solutions was evaluated visually and using a separation analyser. Photocatalytic activity of nanoparticles was studied by photo‐activated degradation reaction of Rhodamine B dyestuff in aqueous solutions. The results showed that grafted particles had acquired enhanced dispersion stability and lower photocatalytic activity in aqueous solutions. Untreated TiO2 dispersions settled rapidly and sedimentation completed within 24 h through the coagulation mechanism, whereas that of the silica‐treated nanoparticles, depending on the silica content, showed different degrees of stability by flocculation mechanism. Photodebleaching of Rhodamine B in the presence of treated nanoparticles is evident by weaker intensity of UV absorption peak of 554 nm due to lowering concentration of Rhodamine B accompanied with the blue shift in UV absorption peaks. However, untreated TiO2 nanoparticles showed only weaker intensity of UV absorption peak. Copyright © 2011 John Wiley & Sons, Ltd.
Interaction between model poly(ethylene terephthalate) thin films and weakly ionised oxygen plasma
Authors: Doliška Aleš , Vesel Alenka , Kolar Metod , Stana‐Kleinschek Karin , Mozetič Miran 
Published: April 2011

AbstractModel films of poly(ethylene terephthalate) were treated by oxygen plasma in order to quantify the etching rate and estimate the contribution of charged and neutral particles to the reaction probability. Model films with a thickness of 50 nm were deposited on a quartz crystal of a microbalance (QCM) by spin‐coating technique. The samples were exposed to oxygen plasma with the positive ion density of 4 × 1015 m−3 and neutral oxygen atom density of 6 × 1021 m−3. The etching rate was determined from the QCM signal and was 4.7 nm s−1. The etching was found rather inhomogeneous as the atomic force microscopic images showed an increase of the surface roughness as a result of plasma treatment. The model films were completely removed from the surface of the quartz crystals in about 12 s. Knowing the etching rate and the flux of oxygen atoms to the surface allowed for calculation of the reaction probability which was found to be rather low at the value of 1.6 × 10−4. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of Influencing Factors on Distribution Behaviors of Vanadium between Hot Metal and FeO‐SiO2‐MnO (‐TiO2) Slag System
Authors: Zhang Y. L. , Zhao F. , Wang Y. G. 
Published: April 2011

AbstractThe distribution behavior of vanadium between a hot metal and a FeO‐SiO2‐MnO (‐TiO2) slag system was studied under laboratory conditions, together with the effects of influencing factors such as temperature, slag composition, the ratio of slag to hot metal, and the initial Si and/or Ti content in hot metal. The results suggested that in a ternary FeO‐SiO2‐MnO slag system, with an increase in temperature and an increase in the SiO2 content of slag, the extraction ratio ($\eta _{V} $), distribution ratio of V ($L_{V} $) and the vanadium capacity of the slag ($C_{VO_{3} {}^{3{-} } } $) decreased, while the effect of MnO content in slag showed a different tendency under different situations. For both high and low ratios of slag to hot metal, the extraction ratio of V reached its maximum value under slag compositions of 13%–25% MnO and 10%–24% SiO2, which correspond to the regions with lower melting point and lower viscosity of the slag. In a quaternary FeO‐SiO2‐MnO‐TiO2 slag system,$\eta _{V} $,$L_{V} $, and $C_{VO_{3} {}^{3{-} } } $ decreased, while the activity coefficient of V2O3 increased, as the TiO2 content increased. Further, the data suggested that under laboratory conditions the effects of influencing factors on the extraction ratio of V from hot metal decreased in the following order: final slag composition > temperature > initial Si and/or Ti content in hot metal.
A lvt‐type Framework [Cu2(tza)4]·ClO4·4H2O Derived from 1H‐tetrazole‐1‐acetic Acid
Authors: Ma Li , Peng Guo , Cai Jin‐Biao , Deng Hong , Zeller Matthias 
Published: April 2011

AbstractThe reaction of 1H‐tetrazole‐1‐acetic acid (Htza) and perchloric acid with cuprous chloride with slow evaporation at room temperature gave a novel 3D porous CuII coordination polymer, [Cu2(tza)4]·ClO4·4H2O (1), (tza = tetrazole‐1‐acetate). The structure exhibits an unusual 3D microporous coordination framework built up by four coordinated CuII nodes and bidentate bridging tza ligands with lvt‐type topology. Furthermore, the magnetic properties of complex 1 were also investigated.
Polymorph of Dibenzo‐24‐Crown‐8 and its Mercury Complex
Authors: Crochet Aurelien , Kottelat Emmanuel , Fleury Antoine , Neuburger Markus , Fromm Katharina M. 
Published: April 2011

AbstractDibenzo‐24‐crown‐8 is studied herein as a flexible ligand able to adopt different conformations, as well as for the complexation of mercury. The recrystallization of dibenzo‐24‐crown‐8 (DB24C8) from dry THF gives a new polymorphic structure of this ligand. This new structure is described and compared to the literature compound. Additionally, coordination of this ligand to mercury iodide HgI2 is studied.
Dietary dilemmas in the management of glycogen storage disease type I
Authors: Bhattacharya Kaustuv 
Published: April 2011

AbstractOver the last 50 years, understanding the biochemical bases of glycogen storage disease type I has led to vastly improved survival and health outcomes but the management still centres around an extremely intensive dietary regimen. Patients’ metabolic profiles are really determined by the whole of the diet and it can be very difficult to adjust therapy accordingly. In an iso‐energetic diet with reference total energy intake, high carbohydrate intake could compromise other macro‐ and micro‐nutrients; if carbohydrates are not restricted then total energy intake is excessive. The quality of the macronutrient such as the glycemic index of carbohydrate, the type of sugar and the proportion of medium–chain triglyceride and essential fatty acids also has a bearing on an individual's long‐term metabolic control with potential clinical correlates. These factors as well as the different requirements between individuals and within individuals as they get older mean that the management of glycogen storage disease type I is particularly fraught. Regular clinical and dietary review is imperative as patients grow, ensuring adequate but not excessive low glycaemic index carbohydrate intake, appropriate dynamic biochemical profiles and suitable age appropriate eating patterns. Without diligent management, and education that empowers the patient, these individuals can struggle in adult life.
Extended Family Impact of Genetic Testing: The Experiences of X‐linked Carrier Grandmothers
Authors: Lehmann Anna , Speight Beverley S. , Kerzin‐Storrar Lauren 
Published: April 2011

AbstractIn many cases, X‐linked conditions are transmitted through families “silently” until the first affected individual is diagnosed. Grandmothers are often then tested to help determine the risk to other family members. To date, psychosocial research on carriers of X‐linked conditions has focused primarily on mothers and sisters of affected males. In the wider social science literature, studies on grandparents of children with disabilities have centered on their role within the family and relationship with the grandchild. We therefore know little about the impact of carrier testing for a genetic condition on grandparents. This qualitative study aims to contribute towards filling that gap. This study included thirteen grandmothers in families with Fragile X or Duchenne muscular dystrophy; ten had living affected grandsons and three had daughters who chose not to continue with affected male pregnancies after prenatal diagnosis. All thirteen took part in semi‐structured interviews and provided a rich and varied data source for conducting thematic analysis. Most of the grandmothers expressed recurring feelings of guilt and a strong sense of responsibility for what had occurred in the family. Other themes included feelings of shock after receiving their test result, changes in family relationships and searching to make sense of the inheritance within the context of the family's experience. This study provides evidence that X‐linked carrier testing can have a profound and lasting impact on grandmothers. Although genetic counseling for X‐linked conditions is often focused on the potential reproductive implications for carriers, these findings suggest that grandmothers should also be offered genetic counseling when tests are carried out, because of the likely psychosocial impact of a positive test result.
Unique bioactivities of bone morphogenetic proteins in regulation of reproductive endocrine functions
Authors: Otsuka Fumio , Inagaki Kenichi 
Published: April 2011

AbstractRemarkable progress has been made in understanding the mechanism by which growth factors and oocytes can regulate the development and function of granulosa cells. Insufficiency of two oocyte‐specific growth factors, growth differentiation factor‐9 and bone morphogenetic protein (BMP)‐15, cause female infertility. Expression of mRNA and/or protein for the BMP system components, including ligands, receptors and intracellular signal transduction factors, was demonstrated in cell components of growing preantral follicles, and biofunctional experiments have further revealed many important roles of the BMP system in regulation of reproductive function. In this review, recent advances in studies on biological actions of BMPs in ovarian folliculogenesis and in related endocrine tissues are discussed.