bluuebunny/crossref_metadata_2025_split huggingface dataset:
Highly Efficient Oxygen‐Storage Material with Intrinsic Coke Resistance for Chemical Looping Combustion‐Based CO2 Capture
Authors: Imtiaz Qasim , Kurlov Alexey , Rupp Jennifer Lilia Marguerite , Müller Christoph Rüdiger 
Published: April 2015

AbstractChemical looping combustion (CLC) and chemical looping with oxygen uncoupling (CLOU) are emerging thermochemical CO2 capture cycles that allow the capture of CO2 with a small energy penalty. Here, the development of suitable oxygen carrier materials is a key aspect to transfer these promising concepts to practical installations. CuO is an attractive material for CLC and CLOU because of its high oxygen‐storage capacity (20 wt %), fast reaction kinetics, and high equilibrium partial pressure of oxygen at typical operating temperatures (850–1000 °C). However, despite its promising characteristics, its low Tammann temperature requires the development of new strategies to phase‐stabilize CuO‐based oxygen carriers. In this work, we report a strategy based on stabilization by co‐precipitated ceria (CeO2−x), which allowed us to increase the oxygen capacity, coke resistance, and redox stability of CuO‐based oxygen carriers substantially. The performance of the new oxygen carriers was evaluated in detail and compared to the current state‐of‐the‐art materials, that is, Al2O3‐stabilized CuO with similar CuO loadings. We also demonstrate that the higher intrinsic oxygen uptake, release, and mobility in CeO2−x‐stabilized CuO leads to a three times higher carbon deposition resistance compared to that of Al2O3‐stabilized CuO. Moreover, we report a high cyclic stability without phase intermixing for CeO2−x‐supported CuO. This was accompanied by a lower reduction temperature compared to state‐of‐the‐art Al2O3‐supported CuO. As a result of its high resistance towards carbon deposition and fast oxygen uncoupling kinetics, CeO2−x‐stabilized CuO is identified as a very promising material for CLC‐ and CLOU‐based CO2 capture architectures.
Soft‐fault diagnostic method based on locus circle of steady‐state node‐voltage vector
Authors: Li Zhihua , Li Liuchang 
Published: April 2015

SummaryThis study describes a relationship between an element parameter and a fault feature steady‐state node‐voltage vector (SSNVV). The locus of the SSNVV endpoints is proposed and proven to be an arc of circle under certain conditions, whereas the element parameter varies from small to large within a certain range. The arc of circle is called locus circle of SSNVV (LCoSSNVV). An LCoSSNVV‐based soft‐fault diagnostic method is also proposed. The method utilizes three discrete SSNVV endpoints to draw an LCoSSNVV for each element and collects all LCoSSNVVs to produce an LCoSSNVV set for fault diagnosis. In the following diagnostic process, the method measures a fault feature SSNVV of actual faulty circuit and judges which element is faulty on the basis of the relationship between the measured fault feature SSNVV and the LCoSSNVVs in an LCoSSNVV set. Subsequently, the fault can be further subdivided into different types of soft faults on the basis of the relative position of the SSNVV on the LCoSSNVV. A range of the faulty element parameter value can be estimated. Several examples illustrate the method. A measurement solution of SSNVV and a solution of a programming strategy are described. The new LCoSSNVV‐based method would effectively improve the soft‐fault diagnosis process of a linear time‐invariant circuit network. Copyright © 2015 John Wiley & Sons, Ltd.
Towards New Disaster Governance: Subsidiarity as a Critical Tool
Authors: Melo Zurita Maria de Lourdes , Cook Brian , Harms Louise , March Alan 
Published: May 2015

AbstractMajor natural disasters are events where day‐to‐day governance activities are disrupted and a large range of different actors – governmental and non‐governmental – are required to (re)act. Given the inherently chaotic nature of disaster events, and the diverse groups responding to their attendant impacts, clarity about how authority and responsibility are allocated across key disaster management actors is essential. This raises numerous pertinent questions: Are there areas of shared competence between different disaster management actors? Is there a need for them to act in common? Is credible cooperation feasible? Can responsibilities be allocated in a clear and effective manner? In this paper, drawing upon the subsidiarity principle, we provide a review of the academic literature using the role of different actors in disaster management in Australia as the case. The objective of the paper is to synthesise what is known and to, thereby, provoke greater conversation and research of responsibilities during disaster events in Australia and beyond. The ultimate contribution is to help understand how the roles of different disaster management actors can be better reconciled to ensure more effective and efficient outcomes. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment
Bioremediation of contaminated water with unnatural dye using blue‐green alga spirulina platensis
Authors: Deniz Fatih , Kepekci Remziye Aysun 
Published: April 2015

Blue‐green alga Spirulina platensis as a cheap biosorbent was tested for its ability to remove a common azo dye, C.I. Basic Red 46 (C.I. BR 46), from contaminated water. Dye biosorption was a quick process and biosorption reaction reached equilibrium within 60 min. The pseudo‐first‐order, pseudo‐second‐order, logistic, and intraparticle diffusion models were used for the kinetic evaluation. The logistic model presented the best fit to the experimental data. The biosorption data were analyzed using Freundlich, Langmuir, and Dubinin‐Radushkevich isotherm models. Langmuir model fitted better to the equilibrium data than Freundlich model. The maximum dye biosorption capacity was obtained as 25.46 mg g−1 for the biosorbent. Dubinin‐Radushkevich model showed that the predominant mechanism of the dye biosorption was likely physical biosorption. This study suggests promising biosorption potential of S. platensis for C.I. BR 46 removal from contaminated effluents. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1414–1419, 2015
Chaim Weizmann as a Scientist – From Berlin to the End of His Manchester Period
Authors: Rappoport Zvi 
Published: April 2015

AbstractAfter finishing high school in Pinsk, Russia, Chaim Weizmann studied two semesters in the Technical University of Darmstadt, returned home for a year, and in 1895 registered as a chemistry student at the Charlottenburg Technical University at Berlin. He studied and worked in the research group of A. Bistrzycki on synthetic dyestuffs and received a patent in the field. He graduated after 3 years and followed Bistrzycki to Freiburg, Switzerland, where he received in January 1899 a Ph.D. degree with a grade of Magna cum laude. He became a Privatdocent at the University of Geneva, worked in Prof. C. Graebe’s group, published papers and patents and sold patents. In 1904, he moved to the University of Manchester in the UK and collaborated with Prof. William Henry Perkin Jr. in research on synthetic dyestuffs and natural products, and started to work with him on the synthesis of acetone by fermentation. He failed to be nominated to Perkin’s chair when Perkin left in 1913, but became a Reader and head of the biochemistry laboratory. After a conflict with Perkin, he continued alone with the acetone synthesis project, found a bacterium that fermented the starch of corn, potatoes, and chestnuts to acetone and butyl alcohol, which was more efficient than a bacterium found by Perkin and co‐workers. The urgent need for acetone in World War One for military purpose and the high yield of his bacterium in acetone‐producing fermentation, compared with the bacterium of his competitors, made Weizmann’s process the favored one by the British military during the war. Weizmann scaled up acetone production and increased its yield by increasing the sophistication of the process by using a high degree of sterilization. For his contributions he is regarded as the father of industrial biotechnology. His contribution to the war effort opened the door to the British leadership in his Zionistic activity. However, this activity and his scientific activity at later periods are not covered in this article.
Borrowing Constraints and Credit Demand in a Developing Economy
Authors: Ruiz‐Tagle Jaime , Vella Francis 
Published: May 2015

SummaryThis paper investigates the determinants of credit demand in the presence of borrowing constraints in a developing economy. We model the determinants of observed debt for Chilean households while accounting for selection bias and the endogeneity of their income and specific household assets. Using a novel Chilean dataset, we estimate the relationship between household characteristics and consumer and mortgage debt. We find substantial differences in the nature of these relationships across the types of debt. For example, we find that the income elasticity for consumer debt is greater than 1 whereas for mortgage debt it is not. The results suggest the increased availability of credit, combined with the aging of the Chilean population, is likely to drastically change the distribution and level of Chilean debt. These findings are particularly relevant for other developing economies currently experiencing rapid income and debt growth. Copyright © 2015 John Wiley & Sons, Ltd.
Fabrication of silk fibroin film using centrifugal casting technique for corneal tissue engineering
Authors: Lee Min Chae , Kim Dong‐Kyu , Lee Ok Joo , Kim Jung‐Ho , Ju Hyung Woo , Lee Jung Min , Moon Bo Mi , Park Hyun Jung , Kim Dong Wook , Kim Su Hyeon , Park Chan Hum 
Published: May 2015

AbstractFilms prepared from silk fibroin have shown potential as biomaterials in tissue engineering applications for the eye. Here, we present a novel process for fabrication of silk fibroin films for corneal application. In this work, fabrication of silk fibroin films was simply achieved by centrifugal force. In contrast to the conventional dry casting method, we carried out the new process in a centrifuge with a rotating speed of 4000 rpm, where centrifugal force was imposed on an aluminum tube containing silk fibroin solution. In the present study, we also compared the surface roughness, mechanical properties, transparency, and cell proliferation between centrifugal and dry casting method. In terms of surface morphology, films fabricated by the centrifugal casting have less surface roughness than those by the dry casting. For elasticity and transparency, silk fibroin films obtained from the centrifugal casting had favorable results compared with those prepared by dry casting. Furthermore, primary human corneal keratocytes grew better in films prepared by the centrifugal casting. Therefore, our results suggest that this new fabrication process for silk fibroin films offers important potential benefits for corneal tissue regeneration. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 508–514, 2016.
Arctigenin, a Natural Lignan Compound, Induces Apoptotic Death of Hepatocellular Carcinoma Cells via Suppression of PI3‐K/Akt Signaling
Authors: Jiang Xiaoxin , Zeng Leping , Huang Jufang , Zhou Hui , Liu Yubin 
Published: April 2015

ABSTRACTIn this study, we explored the cytotoxic effects of arctigenin, a natural lignan compound, on human hepatocellular carcinoma (HCC) cells and check the involvement of phosphatidylinositol 3‐kinase (PI3‐K)/Akt signaling. HCC cells were treated with different concentrations of arctigenin and cell viability and apoptosis were assessed. Manipulating Akt signaling was used to determine its role in the action of arctigenin. Arctigenin significantly inhibited the viability of HCC cells in a concentration‐dependent manner. Arctigenin induced apoptosis and activation of caspase‐9 and ‐3. Overexpression of a constitutively active Akt mutant blocked arctigenin‐induced apoptosis. Combinational treatment with arctigenin and the PI3‐K inhibitor LY294002 significantly enhanced apoptosis. Arctigenin reduced the expression of Bcl‐xL, Mcl‐1, and survivin and the phosphorylation of mTOR and S6K, which were significantly reversed by overexpression of constitutively active Akt. This is the first report about the anticancer activity of arctigenin in HCC cells, which is mediated by inactivation of PI3‐K/Akt signaling.
Synthesis and Cyclization of Sulfur‐Substituted Azido Dienes to Pyrrolizidine and Indolizidine Moieties
Authors: Chou Shang‐Shing P. , Tsao Hung‐Juan , Lee Chien‐Ming , Sun Chung‐Ming 
Published: May 2015

AbstractSulfur‐substituted azido dienes 1 and 11, conveniently prepared from the corresponding 3‐sulfolenes 5 and 10, were thermolyzed to give pyrrolizidine and indolizidine products, 6, 7 and 14.
Additional Alkaloids from Phoebe Formosana
Authors: Lee Shoei‐Sheng , Tsai Fang‐Yeh , Chen Ih‐Sheng , Liu Karin C. S. 
Published: May 2015

AbstractFour additional phenolic bases ‐ laurotetanine (2), asimilobine (3), norjuziphine (4) and juziphine (5) ‐ were isolated during the reinvestigation of the roots of P. formosana by combination of centrifugal partition chromatography and common separation methods. The latter two bases are first isolated from Lauraceous plants. Their structures were elucidated mainly by NMR spectral analysis.
Electrochemical Reduction of Substituted Anthracenes
Authors: Cheng Ellen , Sun Ta‐Chien , Oliver Su Y. 
Published: May 2015

AbstractA systematic investigation of the electrochemical reduction of substituted anthracenes in N,N‐dimethylformamidc has unveiled the reductive properties of the aromatic compounds. For the anthracenes with a reversible first reduction, the redox potential exhibits linearity vs a value of the Hammett equation. For anthracenes with an irreversible first reduction, the electron transfer and chemical reaction occur via either a sequential or a concerted pathway. When the irreversible first reduction occurs at a potential more negative than E1/2 calculated from the σ value, the reaction occurs via a sequential pathway, such as for 9‐chloroanthracene. When the irreversible first reduction occurs at a potential more positive than the expected E1/2, the reaction occurs via a concerted mechanism of electron transfer and bond breaking, such as for 9‐chloromethylanthracenc. The displacement of the halide results in the parent polyaromatic hydrocarbons, as in dicated by the spectroelectrochemical method.
OPSAES: Organic Pollutants Sampling and Analysis Expert System
Authors: Chen Chi‐Ping , Ling Yong‐Chien 
Published: May 2015

AbstractSampling and analyses using standard methods has been the most efficient means to obtain reliable results. Standard method selection has relied heavily on the analyst's heuristic and algorithmic capabilities. An integrated expert‐database system, OPSAES, was developed to stimulate this expertise that would assist the user to select methods to sample and analyze organic pollutants via specification of analytical descriptors. The merits of improvements in environmental analytical data generation process through the use of OPSAES are demonstrated.
Phospholipase A2‐Catalyzed Hydrolysis of 1,2‐DimyristoyI‐sn‐Glycero‐3‐Phosphocholine in Organic Solvents
Authors: Wu Fang‐Chen , Lin Gialih 
Published: May 2015

AbstractThe phospholipase A2‐catalyzed hydrolysis of phosphatidylcholine in organic solvents is described. The effects of various sources of enzymes are discussed; among five phospholipases A2, bee venom enzyme has the greatest activity, Naja naja venom and Naja mocambique enzymes have moderate activities, and pancreatic enzymes have the least activities. The effects of adducts such as alcohols, ether, and bovine serum albumin in chloroform on this catalysis are discussed; adducts, such as ether or alcohol, in small proportions increased the hydrolysis rate, but in large proportions inhibited hydrolysis. Bovine serum albumin increased slightly the phospholipase A2 catalysis rate. From the effect of temperature on this catalysis in chloroform, the substrate conformation at the α‐memylcne region of acyl chains is a major factor for activation of phospholipases A2, confirming our previous conclusion that the substrate conformation is an important factor in the activation of phospholipase A2.
Kinetic Methods of Analysis: How Do They Rate?
Authors: Crouch Stanley R. 
Published: May 2015

AbstractDuring the past few years there has been a resurgence of interest in kinetic aspects of analytical chemistry and in kinetic methods of analysis. The increased activity is a result of advances that have been made in instrumentation and in data processing techniques. Still, the kinetic approach is not widely applied by practicing analytical chemists. Why is this true? Why are kinetic methods not among the most common methods in use by analytical chemistry? This paper discusses the advantages and limitations of kinetic methods and addresses the probable reasons that they are not widely used. Several new principles have cmerged that are guiding the development of new kinetic‐based determinations. These developments have made it possible to compensate for errors that result from changes in reaction conditions and to determine accurately multiple components in mixtures. With these advances kinetic methods are approaching the reliability of traditional equilibrium‐based determinations and should be re‐evaluated by analytical chemists.
Applications of Macrocyclic Polyethers in Analytical Sensors and Ion Separation
Authors: Shih Jeng‐Shong 
Published: May 2015

AbstractArtificial macrocyclic polyethers were synthesized and applied as neutral carriers for ion‐selective PVC membrane electrodes, ion‐chromatographic packing materials, extractants and adsorbents for ion separation, coating materials for piezoeletrical membrane sensors for organic species, and ion‐transport carriers through liquid membranes. Ion‐selective electrodes such as those for K+ Na+, UO22+, Cs+, Pb2+, Fe3+, Hg2+ and Ag+ ions based on crown ether‐phosphotungstic acid (PW) precipitates and dithio crown ethers respectively were prepared and showed good sensitivity and selectivity. Crown ether‐PW precipitates were applied as adsorbents of rare‐earth ions and some common heavy‐metal ions. Some rare‐earth ions were easily extracted with crown ethers, especially 15‐crown‐5. Poly(stytene/divinyl benzene) cryptand‐22 resin was synthesized and applied as a bifunctional stationary phase of ion chromatography to separate bom cations and anions, even some organic carboxylate geometric isomers. Crown ethers such as mono‐benzo‐15‐crown‐5 was successfully applied as a coating material on piezoelectric quartz membrane sensors for some organic species. The oscillation frequency of the crown‐ether quartz‐membrane sensor was sensitive to organic vapours such as amines and alcohols. Upon adsorption of organic species on the crown‐ether quartz membrane, the oscillation frequency of the sensor decreased obviously. Special crown ether such as dibenzo‐16‐crown‐5‐oxyacetic acid, decyl‐cryptand‐22 and 1, 4‐dihydro‐pyridine‐18‐crown‐5 were synthesized and successfully applied as ion‐transport carriers (ionophores) for transport of Na+ K+ and Mg2+ ions through liquid membranes.
Comparison of Triple Quadrupole and Double Focusing Mass Spectrometers to Investigate Collision‐Induced Dissociation and Metastable Ions of Glycoconjugates
Authors: Ju Dar‐Der , Li Ding‐Tzai , Wei Guor‐Jien , Her Guor‐Rong 
Published: May 2015

AbstractGlycoconjugates, such as chromophore‐labeled disaccharides and permethylated glycosphingolipids (GSL) were used for comparison of triple quadrupole and double focusing mass spectrometers in analysis of product ions. A profound effect of collision energy was observed in the product ion spectra of ceramide ions (fragment ions of permethylated GSL): more product ions were observed from a double focusing mass spectrometer. Besides collision energy, the structure of the analyte had a significant effect on the formation of product ions. Despite the fact that masses of protonated molecular ions (MH+) of permethylated GSL are significantly larger than their ceramide fragments, the low‐energy and high‐energy product ion spectra of MH+ are, in general, similar. In a double focusing mass spectrometer of reversed geometry, more metastable ions were observed in the first field free region (FFR) than in the second FFR. The metastable ions observed in the second FFR were similar to those observed in low‐energy collision‐induced dissociation (CID). Although a double focusing mass spectrometer is superior to triple quadrupole instrument for detection of product ions, the poor resolution in either the selection of precursor ion or in the product ion spectra can be a serious problem in analysis of a mixture with similar masses.
Lipid and Protein Thermotropic Transition of Porcine Stratum Corneum by Microscopic Calorimetry and Infrared Spectroscopy
Authors: Lin Shan‐Yang , Liang Run‐Chu , Lin Tsung‐Chien 
Published: May 2015

AbstractMicroscopic differential scanning calorimetry and Fourier transform infrared spectrometry (DSC‐FTIR) were combined to investigate the thermal response and IR spectra of lipid and protein in the process of a phase transition in porcine stratum corneum (SC) by KBr disc method. The alterations of bands associated with the CH2 stretching vibrations near 2850 and 2920 cnv−1 were used to determine the phase transformation of lipid with temperature. The peaks of amide I and II of protein were used to investigate the thermal conversion of protein. A reheating process was performed. The results indicate that the bands of lipid near 2900 cm−1 shifted to greater wavenumber with increased temperature, but reversibly. The band due to deformation mode of the lipid altered from shoulder to smooth with increased temperature. During heating, α‐keratin of the protein transformed gradually to p‐keratin, but irreversibly. Thermal transitions that occurred near 78 °C and 115 °C for the sample on first heating were associated with phase transition of the lipid‐protein complex and the protein in porcine SC, respectively. After reheating, this phase transitional temperature of the lipid‐protein complex in porcine SC decreased from 78 to 68 °C, and the transition of protein near 115 °C almost disappeared. This behaviour indicates that porcine SC after heating might alter its structure. The thermally altered proportion of lipid was 43.98% and the thermally induced proportion of protein was 41.48% during the first heating process, but the restoration of lipid during the cycle of heating, cooling and reheating was 37.64%. The variation is attributed to the denaturation of protein to alter the structure of lipid‐protein complex after first heating. This technique was simple, precise and reproducible for simple determination of stratum corneum or biological samples in a brief period.
A Multifractal Approach to Heterogeneous Reactions over Fractal Surfaces
Authors: Lee Chung‐Kung , Liang Wen‐Hau , Lee Shyi‐Long 
Published: May 2015

AbstractMonte‐carlo simulations of modified Eley‐Rideal mechanisms (ER) possessing decay and enhanced sticking probability and a three‐step catalytic reaction (TCR) over fractal surfaces were performed to examine the morphological effect on these surface reactions. Effects of decay and enhancing profiles on the reaction probability distribution (RPD) for the ER reaction and effects of varying probability of reaction steps and cluster sizes on the normalized selectivity distribution (NSD) for TCR were men analyzed with multifractal scaling techniques. For the ER mechanism, RPD tends to be uniform for rapid decay and relatively concentrated at greater enhancing rate. For TCR, increased cluster size is found to decrease the position sensitivity of NSD. A large ratio of dimerization to isomerization increases the position distinction among active sites when the adsorption probability equals to unity. At small p1, i.e., adsorption probability « 1, the ratio of dimerization to isomerization causes no effect on the NSD.