bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biofunctionalization of Multiwalled Carbon Nanotubes by Irradiation of Electropolymerized Poly(pyrrole–diazirine) Films
Authors: Papper Vladislav , Gorgy Karine , Elouarzaki Kamal , Sukharaharja Ayrine , Cosnier Serge , Marks Robert S. 
Published: June 2013

AbstractA photoactivatable poly(pyrrole–diazirine) film was synthesized and electropolymerized as a versatile tool for covalent binding of laccase and glucose oxidase on multiwalled carbon nanotube coatings and Pt, respectively. Irradiation of the functionalized nanotubes allowed photochemical grafting of laccase and its subsequent direct electrical wiring, as illustrated by the electrocatalytic reduction of oxygen. Moreover, covalent binding of glucose oxidase as model enzyme, achieved by UV activation of electropolymerized pyrrole–diazirine, allowed a glucose biosensor to be realized. This original method to graft biomolecules combines electrochemical and photochemical techniques. The simplicity of this new method allows it to be extended easily to other biological systems.
Water‐Soluble Nitric‐Oxide‐Releasing Acetylsalicylic Acid (ASA) Prodrugs
Authors: Rolando Barbara , Lazzarato Loretta , Donnola Monica , Marini Elisabetta , Joseph Sony , Morini Giuseppina , Pozzoli Cristina , Fruttero Roberta , Gasco Alberto 
Published: June 2013

AbstractA series of water‐soluble (benzoyloxy)methyl esters of acetylsalicylic acid (ASA), commonly known as aspirin, are described. The new derivatives each have alkyl chains containing a nitric oxide (NO)‐releasing nitrooxy group and a solubilizing moiety bonded to the benzoyl ring. The compounds were synthesized and evaluated as ASA prodrugs. After conversion to the appropriate salt, most of the derivatives are solid at room temperature and all possess good water solubility. They are quite stable in acid solution (pH 1) and less stable at physiological pH. In human serum, these compounds are immediately metabolized by esterases, producing a mixture of ASA, salicylic acid (SA), and of the related NO‐donor benzoic acids, along with other minor products. Due to ASA release, the prodrugs are capable of inhibiting collagen‐induced platelet aggregation of human platelet‐rich plasma. Simple NO‐donor benzoic acids 3‐hydroxy‐4‐(3‐nitrooxypropoxy)benzoic acid (28) and 3‐(morpholin‐4‐ylmethyl)‐4‐[3‐(nitrooxy)propoxy]benzoic acid (48) were also studied as representative models of the whole class of benzoic acids formed following metabolism of the prodrugs in serum. These simplified derivatives did not trigger antiaggregatory activity when tested at 300 μM. Only 28 displays quite potent NO‐dependent vasodilatatory action. Further in vivo evaluation of two selected prodrugs, {[2‐(acetyloxy)benzoyl]oxy}methyl‐3‐[(3‐[aminopropanoyl)oxy]‐4‐[3‐(nitrooxy)propoxy]benzoate⋅HCl (38) and {[2‐(acetyloxy)benzoyl]oxy}methyl 3‐(morpholin‐4‐ylmethyl)‐4‐[3‐(nitrooxy)propoxy]benzoate oxalate (49), revealed that their anti‐inflammatory activities are similar to that of ASA when tested in the carrageenan‐induced paw edema assay in rats. The gastrotoxicity of the two prodrugs was also determined to be lower than that of ASA in a lesion model in rats. Taken together, these results indicated that these NO‐donor ASA prodrugs warrant further investigation for clinical application.
On the Similarity and Dissimilarity between Photocatalytic Water Splitting and Photocatalytic Degradation of Pollutants
Authors: Pasternak Sagi , Paz Yaron 
Published: June 2013

AbstractThe last four decades have shown a remarkable increase in scientific interest in photocatalysis as a tool for tackling the world’s energy and waste problems. The apparent similarity between photocatalytic water splitting and photocatalytic degradation of pollutants, which have been studied so far by two different scientific communities, raises the question regarding the extent to which one may utilize knowledge obtained in one field for the benefit of the other. This review examines the common features and differences between the two areas. The main similarities stem from the common dependence on the absorption of photons and on subsequent charge‐carrier dynamics. The main dissimilarities are linked to thermodynamics, the type of reactants and end products, and to the role of adsorption and desorption. At present the fundamental differences between storing energy and using it to solve environmental issues affect practical solutions. Yet, easy transfer of knowledge, research resources, and personnel between the two is not only possible but should be encouraged.
Effects of dynamic and non‐dynamic element changes in RC and RL networks
Authors: Berger Thomas , Halikias George , Karcanias Nicos 
Published: June 2013

AbstractThe paper deals with the redesign of passive electric networks by changes of single dynamic and non‐dynamic elements which may retain or affect the natural topology of the network. It also deals with the effect of such changes on the natural dynamics of the network, the natural frequencies. The impedance and admittance modeling for passive electrical networks is used which provides a structured, symmetric, integral‐differential description, which in the special cases of RC and RL networks is reduced to matrix pencil descriptions. The transformations on the network are expressed as those preserving, or modifying the two natural topologies of the network, the impedance graph and the admittance graph topologies. For the special cases of RC and RL networks, we consider the problem of the effect of changes of a single dynamic or non‐dynamic element on the natural frequencies. Using the Determinantal Assignment Framework, it is shown that the family of single parameter variation problems is reduced to equivalent Root Locus problems with the possibility of fixed modes. An explicit characterization of the fixed modes is given, and a number of interesting properties of the spectrum are derived such as the interlacing property of poles and zeros for the entire family of Root Locus problems. Copyright © 2013 John Wiley & Sons, Ltd.
Facile Synthesis of Functional Tricyclic Fused Furans by Intramolecular Wittig Reactions
Authors: Tsai Yi‐Ling , Das Utpal , Syu Siang‐en , Lee Chia‐Jui , Lin Wenwei 
Published: June 2013

AbstractA convenient protocol for the preparation of tricyclic fused furans in one step starting from acid chlorides and Michael acceptors is described. The reaction conditions are mild, operationally simple, and have a broad substrate scope. The reaction is believed to proceed by an intramolecular Wittig reaction with a phosphorus ylide as the key intermediate.
Microsensor Chip Integrated with Gold Nanoparticles‐Modified Ultramicroelectrode Array for Improved Electroanalytical Measurement of Copper Ions
Authors: Wang Jinfen , Bian Chao , Tong Jianhua , Sun Jizhou , Xia Shanhong 
Published: June 2013

AbstractThis paper presents a microsensor chip integrated with a gold nanoparticles‐modified ultramicroelectrode array (UMEA) as the working electrode for the detection of copper ions in water. The microsensor chip was fabricated with Micro‐Electromechanical System technique. Gold nanoparticles were electrodeposited onto the surface of UMEA at a constant potential of −0.3 V. The ratio d/Rb of interelectrode spacing (d) over the individual electrode’s radius (Rb) was investigated to improve the electrochemical performance. The UMEA with a d/Rb of 20 showed the best hemispherical diffusion mode, resulted in fast response time and high current response. The gold nanoparticles increased the active surface area of UMEA by not changing the geometries of UMEA, and the current response was increased further. Incorporating the optimized characteristic of UMEA and gold nanoparticles, the microsensor showed a good linear range from 0.5 to 200 µg L−1 of copper ions in the acetate buffer solutions with the method of square wave stripping voltammetry. Compared with the gold nanoparticles‐modified disk electrode, the gold nanoparticles‐modified UMEA showed higher sensitivity (0.024 µA mm−2 µg−1 L) and lower limit of detection (0.2 µg L−1). Water samples from river water and tap water were analyzed by the microsensor chip with recovery ranging from 100.7 % to 107.8 %.
Self‐Assembled Regenerated Cellulose Spacer Film in Thin Film and Generator‐Collector Electrodes
Authors: Vuorema Anne , Sillanpää Mika , Vehviläinen Marianna , Kamppuri Taina , Nousiainen Pertti , Thielemans Wim , Marken Frank 
Published: June 2013

AbstractReconstituted cellulose spontaneously self‐assembles at surfaces from an alkaline cellulose solution (ca. 1 wt%, pH 14, prepared with an enzymatic method from wood pulp) into porous films with approximately 300 nm thickness per layer, for example onto immersed tin‐doped indium oxide (ITO) electrodes. Sequential multi‐layer deposition allows control over the thickness of the assembled films. The hydrophilic properties of the cellulose film electrodes are utilised here (i) as dip‐probe with capillary force picking up sample solution and (ii) as flow‐through generator‐collector probe, for example for future application in in situ chromatographic separation in end‐column detection with nano‐molar sensitivity.
Ultraporous Palladium Supported on Graphene‐Coated Carbon Fiber Paper as a Highly Active Catalyst Electrode for the Oxidation of Methanol
Authors: Sawangphruk M. , Krittayavathananon A. , Chinwipas N. , Srimuk P. , Vatanatham T. , Limtrakul S. , Foord J. S. 
Published: June 2013

AbstractUltraporous Pd nanocrystals for electrocatalysis applications were fabricated using a direct electrodeposition method on three differing carbon supports: flexible carbon fiber paper (CFP), and CFP modified with either graphene oxide nanosheets or their chemically reduced forms using a simple spray coating technique. The electrocatalytic activity of these electrodes was investigated for the direct electro‐oxidation reaction of methanol in alkaline media. Pd deposited on the CFP modified with reduced graphene oxide (rGO) has excellent poisoning tolerance to carbonaceous species and a significantly better catalytic activity toward methanol oxidation than the other two catalyst support materials. Pd/rGO/CFP in 2.0 M CH3OH in 2.0 M NaOH yields a specific current density of 241 mAmg–1 cm–2 determined at the anodic oxidation peak. It is believed that the collaborative effects due to the three‐dimensional ultraporous Pd nanocrystals and fast electron transfer owing to high conductivity of rGO nanosheets play an important role in enhancing the catalytic performance of Pd/rGO/CFP toward methanol oxidation in alkali media.
In utero and lactational exposure to 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin modulates dysregulation of the lipid metabolism in mouse offspring fed a high‐calorie diet
Authors: Sugai Etsuko , Yoshioka Wataru , Kakeyama Masaki , Ohsako Seiichiroh , Tohyama Chiharu 
Published: June 2013

ABSTRACTExposure to environmental chemicals, including dioxins, is a risk factor for type 2 diabetes mellitus in humans. This study explored the hypothesis that in utero and lactational exposure to 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD), the most toxic congener among dioxins, aggravates this disease state later in adulthood. Pregnant C57Bl/6 J mice were administered either a single oral dose of TCDD (3.0 µg kg–1 body weight) or corn oil on gestational day 12.5. The male pups born to these two groups of dams were given either a regular diet or a high‐calorie diet, after postnatal day (PND) 28. The four groups of investigated offspring were thus termed T‐R (TCDD regular diet), T‐H (TCDD high‐calorie diet), V‐R (vehicle regular diet), and V‐H (vehicle high‐calorie diet). The mice were regularly monitored for body weight, blood pressure and glucose, until they reached 26 weeks of age. Mice in the V‐H group were significantly obese at weeks 15 and 26, but they exhibited no diabetes‐associated signs of insulin resistance or hypertension. However, metabolic syndrome‐related alterations with marginal signs of liver damage were found at week 26. Pronounced signs of dysregulated lipid metabolism with altered gene expression and liver inflammation were already present at week 15, whereas such alterations were suppressed in the T‐H group. Although the mechanism is unclear, this study showed that in utero and lactational exposure to low‐dose TCDD does not aggravate obesity‐induced disease states, such as adult‐onset diabetes, but instead attenuates the dysregulation of lipid metabolism brought on by a high‐calorie diet. Copyright © 2013 John Wiley & Sons, Ltd.
Using Non‐Destructive Analysis Techniques to Examine the Artworks of Taiwanese Artist Cheng‐Po Chen (1895‐1947)
Authors: Wu Han‐Chung , Soraluze Ioseba I. , Chen Li‐Po , Huang Ping‐Chih , Kuei Chun‐Hsiung 
Published: June 2013

AbstractThis study employed the non‐destructive techniques to analyze and examine the artworks of the Taiwanese artist Cheng‐Po Chen (1895‐1947) for disclosing the damage to Chen's artworks and determine his creation habits. Ten pieces of artworks that required restoration were examined using ultraviolet examination techniques. Based on the differences in their fluorescence characteristics, various parts of these works were shown to have been retouched, thus, original and retouched regions were distinguished. Examining these works using Infrared instrument revealed that Chen did not use charcoal to prepare drafts, and he directly applied oil paint to the canvases. Subsequently, these two examination techniques were adopted to examine sketches. The results showed that residues imprinted on them cause of storage methods were organic materials from charcoal and not carbon granules. The X‐ray examination identified numerous creations beneath the surface of several artworks. The X‐ray fluorescence spectrometer was used for elemental analysis of the pigments. The results corresponded with the pigments listed in Chen's purchase form, thus, we summarized the composition of palettes used by Chen. In general, this study acquired a considerable amount of information from the pigment examinations and established a database of the pigments that Chen commonly employed in his artworks.
Switchable Interporphyrin Interaction in an Anthraquinone‐Bridged Porphyrin Dimer
Authors: Mai Chi‐Lun , Huang Yi‐Lin , Chiu Chien‐Lan , Lin Hsin‐Yu , Lin You‐Shiang , Yeh Chen‐Yu 
Published: June 2013

AbstractThe synthesis of porphyrin dimer and monomer with an anthraquinone or diacetoxyanthracene unit has been achieved. The electronic absorption spectra show that the anthracene‐bridged porphyrin dimer 2 has strong electronic coupling between the two porphyrin units as evidenced by significant band broadening whereas the anthraquinone‐bridged dimer 1 does not show electronic communication. Porphyrin dimer 2 shows two overlapping 1‐e− oxidation processes at E1/2(ox1) = +0.94 and E1/2(ox2) = +1.01 V, corresponding to the first electron abstraction from the two porphyrin units and porphyrin 1 shows a two 1‐e− waves at +1.01, indicating no electronic coupling between the two porphyrin units. The anthraquinone‐bridged system can be reversibly switched from cross conjugated (switch off) to linear conjugated (switch on) via two‐electron reduction/oxidation reactions. This feature holds promise for the anthraquinone‐based wires to be used as redox‐controlled switches in molecular electronic devices.
The removal of cesium ion with natural Itaya zeolite and the ion exchange characteristics
Authors: Endo Masatoshi , Yoshikawa Eishi , Muramatsu Natsumi , Takizawa Norifumi , Kawai Takahiro , Unuma Hidero , Sasaki Atsushi , Masano Akihisa , Takeyama Yoshiyuki , Kahara Tomoo 
Published: June 2013

AbstractBACKGROUNDThe large Itaya zeolite deposit in Yonezawa, Japan produces good quality, natural zeolite. Its properties as an adsorbent and a functional carrier were assessed and the ion exchange characteristics examined. Natural zeolite has a useful high cation exchange capacity, but has a disadvantage in scattering of the powder. In this study a nonwoven fabric containing zeolite was tested for the removal of cesium.RESULTSThe X‐ray diffraction (XRD) peak pattern confirmed that Itaya zeolite is mainly clinoptilolite and contains some mordenite. Ion exchange selectivity of the natural zeolite was Ag+ > Pb2+ > Cu2+ > Zn2+ > Cd2+ > Cr3+ > Ni2+ with almost 100% removal of Ag+ and Pb2+ ions.The cation exchange capacity (CEC) of Itaya zeolite was 131 cmol kg‐1. Low concentrations of Cs+ were removed effectively from the solution with natural zeolite. Cesium ions were removed by ion exchange with potassium and sodium. Cs+ was desorbed from the zeolite with ammonium salt solutions. Elution of Cs+ was influenced by the coordination ability of counter anions.CONCLUSIONSatisfactory results were obtained using zeolite‐containing nonwoven fabric for the removal of cesium ions. © 2013 Society of Chemical Industry
Approaches to rehabilitation of radioactive contaminated territories
Authors: Voronina Anna V , Semenishchev Vladimir S , Bykov Alexey A , Savchenko Marina O , Kutergin Andrey S. , Nedobuh Tatjana A 
Published: June 2013

AbstractBACKGROUNDAccidents at nuclear fuel cycle plants may lead to contamination of areas of land and water. Cheap and available sorbents including natural aluminosilicates can be used for rehabilitation and decontamination of large volumes of radioactively contaminated water, including drinking water, prevention of migration of radionuclides into ground and surface waters through the soil and returning contaminated soil to farming.RESULTS AND DISCUSSIONA comparative study of sorption properties of various natural and surface‐modified aluminosilicates with respect to caesium is made. It is shown that sorption features of surface‐modified aluminosilicates for Cs were improved by 100–1000 times compared with respective natural aluminosilicates. It is shown that surface modification of glauconite by a mixed nickel–potassium ferrocyanide phase allows it to considerably increase its specificity (caesium distribution coefficients (2.9 ± 0.8)×103 mL g‐1 for natural and (4.5 ± 0.5)×105 mL g‐1 for modified glauconite) as well as making it selective to caesium in the presence of other alkaline ions and also provides irreversible caesium sorption.CONCLUSIONSDue to improved features, modified aluminosilicates can be more successful than natural ones when used for rehabilitation of radioactive contaminated territories (including agriculture) and water areas, as well as for decontamination of liquid radioactive wastes and for creation of geochemical barriers in solid radioactive waste storage. © 2013 Society of Chemical Industry
Contribution of wind, conductivity, and geomagnetic main field to the variation in the geomagnetic Sq field
Authors: Takeda Masahiko 
Published: June 2013

AbstractLong‐term variation in the geomagnetic Sq field and the cause of the variation were examined. The amplitude of the geomagnetic Y component (Sq(Y)) in equinox was averaged for each year and adopted as a proxy of the Sq field. Sq(Y) was combined with the ionospheric conductivity estimated by the International Reference Ionosphere model to determine the dynamo electric field and neutral wind velocity by using the geomagnetic main field strength. It was found that the solar activity dependence of the Sq field could be almost completely attributed to the conductivity variation, and neutral winds tend to decrease when the solar activity increases. Although the long‐term variation in the dynamo field differed among observatories, these differences were mostly attributed to the locality of the geomagnetic secular variation, whereas the variations in neutral wind amplitude were nearly the same in all regions. On the other hand, no clear long‐term variation in neutral wind was detected other than that by solar activity.
The relative roles of upper and lower tropospheric thermal contrasts and tropical influences in driving Asian summer monsoons
Authors: Dai Aiguo , Li Hongmei , Sun Ying , Hong Li‐Ciao , LinHo  , Chou Chia , Zhou Tianjun 
Published: June 2013

AbstractSummer thermal structure and winds over Asia show a larger land‐ocean thermal gradient in the upper than in the lower troposphere, implying a bigger role of the upper troposphere in driving the Asian summer monsoon circulation. Using data from atmospheric re‐analyses and model simulations, we show that the land‐ocean thermal contrast in the mid‐upper (200–500 hPa) troposphere (TCupper) contributes about three times as much as the thermal contrast in the mid‐lower (500–850 hPa) troposphere (TClower) in determining both the strength and variations of Asian summer monsoon circulations. Tropical sea surface temperature anomalies associated with the annual cycle, El Niño‐Southern Oscillation, decadal changes, and global warming all are accompanied with much larger variations and changes in TCupper than in TClower, partly due to enhanced latent heating aloft from convection. The variations and changes in TCupper and TClower are highly correlated with the strength of the South Asian Summer Monsoon (SASM) and the East Asian Summer Monsoon (EASM) in their respective sectors during the past 50–60 years. In particular, the weakening of the EASM since the 1950s is caused by the weakening mainly in TCupper and secondarily in TClower induced mainly by recent tropical surface warming, although spurious cooling over East Asia seen in reanalysis data may have enhanced this weakening. However, the strength of the SASM and EASM monsoons follows TCupper but decouples with TClower in the global warming case in the 21st century. The results suggest that the TCupper plays a dominant role and provides an efficient mechanism through which tropical oceans can influence extratropical monsoons.
The modified multilevel compressed block decomposition algorithms for analyzing the scattering of objects in half space
Authors: Ding Dazhi , Shen Songge , Jiang Zhaoneng , Chen Rushan 
Published: June 2013

ABSTRACTThe convergence rate of iterative methods can vary in an unpredictable way. It is related to the matrix condition number, which is notoriously bad for the electric field integral equation in the large‐scale electromagnetic problems. Therefore, an efficient direct solution—a multilevel compressed block decomposition (MLCBD) algorithm based on the adaptive cross‐approximation algorithm—is applied to overcome this problem; it is very efficient for the monostatic problems. Simulation results of the objects up and below ground in half space demonstrate that the proposed MLCBD method is efficient for analyzing electromagnetic problems. Copyright © 2013 John Wiley & Sons, Ltd.