bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pressure Rise due to SF6 Arcing and Energy Balance in a Closed Container
Authors: KOTARI MASASHI , TADOKORO TOMO , TANAKA SHIN‐ICHI , IWATA MIKIMASA , AMAKAWA TADASHI 
Published: January 2016

SUMMARYFrom an environmental viewpoint, when carrying out internal arc tests on SF6‐insulated power equipment, it is necessary to prevent SF6 from being released into the atmosphere or to replace SF6 with air in accordance with IEC standards. However, the pressure rise and the thermal effect of the hot gas exhausted during arcing when testing in air are still considerably different from those for testing in SF6. Thus, it is necessary to propose a specific procedure to replace SF6 with air and to select appropriate parameters for the tests. Therefore, it is desirable to clarify the equivalent conditions causing these phenomena both experimentally and analytically. In this paper, we describe the effect of the charged gas pressure in a closed container on the pressure rise due to air and SF6 arcing and the ratio of the arc energy to the energy contributing to the internal pressure rise () from an experimental viewpoint. Additionally, to research the energy balance resulting from SF6 arcing in the container, the energy balance is discussed on the basis of chemical reactions, radiation, and the melting and vaporization of the electrodes. It is found that the maximum pressure rise increases for both gases upon increasing the gas pressure from 0.1 MPa to 0.4 MPa. Subsequently, good agreement with the energy balance was obtained under reasonable assumptions by taking account of the energy components related to the chemical reactions, radiation, and the melting and vaporization of the electrodes. The ratio of the radiation energy loss to the total consumption energy increased upon increasing the charged gas pressure.
Isolated Operation of Power System in Complex Housing Supplied by Battery Energy Storage System and Fuel Cells
Authors: SATO TAIHEI , ARAI JUNICHI , NAGAHIRA TOMOKI , SHINJI TAKAO , OGATA TAKAO , TSUKADA TATSUYA , YAMASHITA AKIRA 
Published: January 2016

SUMMARYFuel cells, as components of cogeneration systems and battery energy storage systems, can be used as power sources in an isolated power system in complex housing at times of blackout. This paper reports study results on such isolated power systems. Simulation models are developed and the results are compared with measured values of active power, reactive power, and voltage. Good agreement is obtained. In this analysis, it is found that there is a stability limit in such inverter power source operation. The stability limit is expressed by a short circuit power ratio that is similar to the one in conventional ac systems. Nonlinear load switching is also studied to demonstrate stable operation.
Defect‐Related Luminescence in ­Nitridoborate Nitride, Mg3Ga(BN2)N2
Authors: Dutczak Danuta , Wurst Kai Matthias , Ströbele Markus , Enseling David , Jüstel Thomas , Meyer H.‐Jürgen 
Published: January 2016

AbstractThe new nitridoborate nitride Mg3Ga(BN2)N2 was prepared by multilateral solid‐state metathesis reaction from MgCl2, GaN, Li3N, and Li3BN2 at high temperature. The crystal structure of Mg3Ga(BN2)N2 was refined from X‐ray powder diffraction patterns isotypically to Mg3Al(BN2)N2 with the space group R$\bar {3}$m no.166 [Z = 3, a = b = 3.4560(0) Å, c = 31.7924(2) Å]. The undoped and Eu2+‐doped Mg3Ga(BN2)N2 show orange‐red luminescence under UV excitation.
Mono‐, Di‐, and Polymeric Pyridino­ylhydrazone ZnII Complexes: Structure and Photoluminescent Properties
Authors: Borbone Fabio , Caruso Ugo , Concilio Simona , Nabha Shiran , Panunzi Barbara , Piotto Stefano , Shikler Rafi , Tuzi Angela 
Published: January 2016

AbstractA series of zinc complexes with tridentate pyridinoylhydrazone ligands bearing two different end groups and coordinated pyridine molecules were synthesized and characterized. Crystal structures with mono‐, di‐, and polymeric arrangements were obtained, depending on the position of the pyridinoyl nitrogen atom. Direct involvement of the pyridinoyl moiety in the coordination to the metal was observed when the nitrogen was in the ortho or meta position. The meta derivatives led to 1D polymers with the same coordination environment, regardless of the bulkiness of the end group. In this case, unprecedented solid‐state photoluminescence quantum yields were recorded. In the ortho ligands, the further bidentate N,N site involving the pyridinoyl nitrogen atom was able to coordinate a further zinc acetate unit. Molecular and periodic calculations were performed within density functional theory (DFT) to rationalize the photophysical behavior. Excellent agreement between the theoretical and experimental absorptions was observed. The HOMOs and LUMOs of the complexes were investigated both in the solid state and in solution.
Solvent Influence on the Magnetic Properties of Iron(II) Spin‐Crossover Coordination Compounds with 4,4′‐Dipyridylethyne as Linker
Authors: Dankhoff Katja , Lochenie Charles , Puchtler Florian , Weber Birgit 
Published: January 2016

AbstractNew iron(II) coordination polymers with solvent‐dependent spin‐crossover behaviour have been synthesised by using an N2O2 Schiff base like ligand and 4,4′‐dipyridylethyne as the bridging axial ligand in different solvents. The effects of different solvents and preparation methods (temperature, concentration) on the magnetic properties have been investigated. Annealing the coordination polymers prepared by the same method but in different solvents led to the same compound exhibiting the same three‐step spin crossover independent of the magnetic properties of the solvated species. The X‐ray structures of the axial ligand, an iron(II) dimer and one of the iron(II) coordination polymers are discussed. Powder X‐ray diffraction analysis was additionally used for further comparison of the compounds.
Facile Synthesis of Cooperative Acid–Base Catalysts by Clicking Cysteine and Cysteamine on an Ethylene‐Bridged Periodic Mesoporous Organosilica
Authors: Ouwehand Judith , Lauwaert Jeroen , Esquivel Dolores , Hendrickx Kevin , Van Speybroeck Veronique , Thybaut Joris W. , Van Der Voort Pascal 
Published: January 2016

AbstractA periodic mesoporous organosilica (PMO) that contains ethylene bridges was functionalized to obtain a series of cooperative acid–base catalysts. A straightforward, single‐step procedure was devised to immobilize cysteine and cysteamine on the support material by means of a photoinitiated thiol‐ene click reaction. Likewise, PMO materials capped with hexamethyldisilazane (HMDS) were used to support both compounds. This resulted in different materials in which the amine site was promoted by carboxylic acid groups, surface silanol groups, or both. The catalysts were tested in the aldol reaction of 4‐nitrobenzaldehyde and acetone. It was found that silanol groups have a stronger promoting effect on the amine than the carboxylic acid group. The highest turnover frequency (TOF) was obtained for an amine‐functionalized material that contained only silanol promoting sites. The loading of the active sites also had a significant effect on the activity of the catalysts, which was rationalized on the basis of a computational study.
Optimized Design of Pt‐Doped Bi2WO6 Nanoparticle Synthesis for Enhanced Photocatalytic Properties
Authors: Lavergne Marie‐Anne , Chanéac Corinne , Portehault David , Cassaignon Sophie , Durupthy Olivier 
Published: January 2016

AbstractThe preparation of photocatalytic heterostructures of platinum on Bi2WO6 nanoparticles by a wet reduction method is described in this report and compared with other preparation methods. The as‐obtained photocatalysts were characterized by XPS and TEM, the results of which confirmed the presence of solely zero‐valent metal nanoparticles on the surface of Bi2WO6. The photocatalytic activity of these heterostructures was evaluated by the degradation of Rhodamine B under blue light (λmax = 445 nm). The deposited noble metal nanoparticles were shown to significantly improve the photocatalytic performance of the bismuth‐based material under visible light. Both the preparation mode and the metal loading may impact on the efficiency. The observed photocatalytic enhancement has been attributed to an electron transfer from the semiconductor to the metal, which prevents fast electron/hole recombination. The electrons trapped in the metals may then participate in the multi‐electron reduction of O2.
Emissive Ruthenium–Bisdiimine Complexes with Chelated Thioether Donors
Authors: Wallenstein Joachim Hedberg , Sundberg Jonas , McKenzie Christine J. , Abrahamsson Maria 
Published: January 2016

AbstractThe photophysical properties of ruthenium(II) complexes of bidentate 2‐[(alkylthio)methyl]pyridine (N,S) ligands have been systematically investigated. The co‐ligands in the heteroleptic complexes were diimines (N,N ligands, e.g., bpy, phen) or tripodal tetradentate tris(2‐pyridylmethyl)amine (tpa). Their X‐ray structures revealed little variation in the Ru–S (2.31–2.33 Å) and Ru–N (2.06–2.11 Å) bond lengths. Despite this, considerable variation can be observed in the electrochemistry and spectroscopy measurements. The presence of the thioether sulfur donor results in a shift to a more positive potential of the Ru2+/Ru3+ process, and the absorption maxima are consequently blueshifted in [Ru(N,N)2(N,S)]2+ complexes compared with the [Ru(N,N)3]2+ analogues. The [Ru(N,N)2(N,S)]2+ complexes display strong room‐temperature emission from 3MLCT states, governed by the N,N donors. This is corroborated by low‐temperature steady‐state emission studies, which revealed typical 3MLCT emission profiles and excited‐state lifetimes of around 5–10 µs.
Fluorescence Quenching in BODIPYs Having Ir‐ and Rh‐Tethered Complexes
Authors: Chu Gong M. , Fernández Israel , Guerrero‐Martínez Andrés , Ramírez de Arellano Carmen , Sierra Miguel A. 
Published: January 2016

AbstractThe effect of Rh‐ and Ir‐centers on the optical properties of the BODIPY core has been studied. To this end, novel metal complexes tethered to BODIPY have been prepared through an easy and versatile procedure using N‐directed C–H activation reactions. The organometallic moiety has a tremendous influence on the emissive properties of the BODIPY fragment. A photoinduced electron transfer (PET) mechanism is suggested to be the main mechanism responsible for the suppression of the BODIPY fluorescence emission in the newly formed dyads. The efficiency of the PET depends on both the distance between the chromophores in the dyad and the nature of the transition metal (Rh vs. Ir).
Development and characterization of solid lipid microparticles containing vitamin C for topical and cosmetic use
Authors: Gu Chengyu , Hu Caibiao , Ma Chaolong , Fang Qiao , Xing Tingkang , Xia Qiang 
Published: January 2016

Solid lipid microparticles (SLMs), combined with the advantages of double emulsions (W/O/W) and water‐in‐oil micro emulsions, are developed for transdermal administration. A modified one‐step emulsification method was introduced, which made the industrial production of SLMs easier. Variables involved in preparation that may affect the solubility, stability, and entrapment efficiency of SLMs were investigated. With vitamin C as a model active, the advantages of SLMs in transdermal administration were studied further. Vitamin C, encapsulated by SLMs, exhibited an enhanced storage stability up to 1 month under 25°C and a sustained releasing profile over 24 h. Furthermore, the SLMs was very helpful in delivering vitamin C molecules into skin through stratum corneum. The result showed 5.52‐fold (p < 0.05) increased absorption of vitamin C, compared to the vitamin C solution. These studies demonstrate that SLMs could be a promising method for facilitating transdermal penetration of active ingredients with high solubility and low permeability.Practical applications: SLMs could be used as a drug delivery system for hydrophilic active ingredients with low permeability. Experiments have shown better stability and skin permeability of vitamin C incorporated in SLMs when compared with pure vitamin C. Furthermore, the method of producing SLMs is simple and can be realized in a way of industrial production. Since SLMs can dissolve in water, SLMs can be directly used on wet skin with excellent skin‐touch feel. As a result, SLMs could be a practical delivery system for hydrophilic compounds with low permeability in many applications such as pharmaceuticals and cosmetics.Solid lipid microparticles (SLMs), combined with the advantages of double emulsions (W/O/W) and water‐in‐oil micro emulsions, are developed for transdermal administration. A modified one‐step emulsification method was introduced, which made the industrial production of SLMs easier. With vitamin C as a model active, the advantages of SLMs in transdermal administration were studied further. Vitamin C, encapsulated by SLMs, showed an enhanced storage stability up to 1 month and a sustained releasing profile over 24 h. Furthermore, the SLMs can facilitate skin's absorption of VC with pig as the model animal. These studies demonstrate that SLMs can be a promising method for facilitating transdermal penetration of active ingredients with high solubility and low permeability.
Acoustic properties of crystallized fat: Relation between polymorphic form, microstructure, fracturing behavior, and sound intensity
Authors: Gregersen Sandra Beyer , Povey Malcolm J. W. , Andersen Morten Daugaard , Hammershøj Marianne , Rappolt Michael , Sadeghpour Amin , Wiking Lars 
Published: January 2016

This study demonstrates a link between the fat crystal network, fracturing behavior, and sound emission upon breakage. SOS, PSO, PPO, and POP rich fats were characterized by SAXS/WAXS and confocal laser scanning microscopy. Simultaneous texture and acoustic analysis was conducted by the use of a texture analyzer connected with an acoustic envelope detector and augmented by a broad band microphone combined with a digital sampling oscilloscope. Results shows a high correlation between negative values of the 2nd derivative of force curves, providing a measure of the energy release, and the sound intensity (r = 0.89, p < 0.05). No relation between acoustic properties and polymorphic behavior, crystal size, or crystal morphology was found. All fats crystallized into a β′ form within 1 day of storage. Subsequently, only the PPO and POP rich fats transformed into the β form (2–4 wk). Evaluation of the relative strength of intra‐ and interparticle links within the fat crystal network, indicate an important role of inter‐particle links for the sound intensity, whereas intra‐particle links were of less importance. It is hypothesized that strong interparticle links provide a strong rigid structure resulting in build‐up of energy during compression and a fast energy release upon breakage accompanied by sound emission.Practical applications: Results from this study provide important knowledge on acoustic properties of fat which can contribute to ensuring a suitable snap, in terms of a high intense sound upon breakage, of chocolate and confectionery products.Acoustic properties of fats are important for the snap of chocolate and confectionery products. This study demonstrates how the breakage sound intensity is significantly correlated with the negative part of the second derivate of force curves, which can be related to a rigid structure due to strong intraparticle links.
One‐Pot Synthesis of Benzopyran‐4‐ones with Cancer Preventive and Therapeutic Potential
Authors: Talhi Oualid , Brodziak‐Jarosz Lidia , Panning Jana , Orlikova Barbora , Zwergel Clemens , Tzanova Tzvetomira , Philippot Stéphanie , Pinto Diana C. G. A. , Paz Filipe A. Almeida , Gerhäuser Clarissa , Dick Tobias P. , Jacob Claus , Diederich Marc , Bagrel Denyse , Kirsch Gilbert , Silva Artur M. S. 
Published: January 2016

AbstractA one‐pot synthesis of novel benzopyran‐4‐ones is described. In a tandem reaction, organobase‐catalysed Michael addition of R1COCH2COR2 on chromone‐3‐carboxylic acid led to decarboxylation and pyran‐4‐one ring opening of the latter. This was followed by chromone‐ and/or chromanone ring closure of the resulting Michael adducts when R1 is an ortho‐hydroxyaryl group. Antioxidant testing of 14 derivatives identified strong antiradical properties of chromanones 3o–r (2.1–3.1 µmol Trolox equiv./µmol compound in the DPPH assay). Chromanones 3p and 3r and 2‐styrylchromone 3k were also most potent in inducing the cytoprotective Keap1‐Nrf2 signalling pathway in a reporter gene assay (fivefold induction at concentrations <3 µM). Of the seven compounds evaluated for antiproliferative activities, 3k and 3r were the most active, inhibiting leukaemia K562 cell proliferation by 50 % after 72 h at concentrations of 4.5 and 7.9 µM, whereas normal peripheral blood mononuclear cells were not affected.
Double π‐Bond Isomerization/Friedel–Crafts Reaction Involving γ‐­Amidocronates: Access to γ‐Aryl/Heteroaryl GABA Scaffolds and Dihydropyrido[1,2‐a]indoles
Authors: Srivastava Anvita , Samanta Sampak 
Published: January 2016

AbstractA series of pharmacologically attractive γ‐indolyl/furyl/aryl‐substituted γ‐amino esters/γ‐aminoketones were obtained in good to high combined yields by π‐bond isomerization of N‐protected γ‐aminocrotonates/γ‐aminocrotonophenones in the presence of triethylamine, followed by tandem Friedel–Crafts alkylation involving several indole/furan/arene derivatives and the resultant N‐protected enamines at room temperature by using B(C6F5)3 (5 mol‐%) as an efficient Lewis acid catalyst. Moreover, the easy synthesis of the important class of 8,9‐dihydropyrido[1,2‐a]indole scaffolds was realized by this unique procedure. Thus, a simple, convenient, and metal‐free‐based protocol may provide an alternative powerful synthetic route for heteroarylation/arylation at the γ positions of GABA derivatives in a practical manner.
4‐Heterosubstituted Cyclopentenone Antiviral Compounds: Synthesis, Mechanism, and Antiviral Evaluation
Authors: Mantione Daniele , Aizpuru Olatz Olaizola , Memeo Misal Giuseppe , Bovio Bruna , Quadrelli Paolo 
Published: January 2016

AbstractRacemic 4‐oxocyclopent‐2‐en‐1‐yl acetate was used in a short synthesis of nucleoside analogues with pyrimidine and purine heterobases. The protocol is based on a typical nucleophilic substitution process. Uracil, thymine, 6‐chloropurine, and some adenines gave the expected 4‐heterosubstituted products along with the isomeric 2‐heterosubstituted compounds as minor components. Samples of selected products were evaluated for their antiviral activity in a primary screening against a variety of viruses belonging to different classes. One of the compounds was found to be highly active against human papilloma virus (HPV).
A Modular Approach to the Asymmetric Synthesis of Cytisine
Authors: Struth Felix R. , Hirschhäuser Christoph 
Published: January 2016

AbstractThe asymmetric synthesis of (+)‐ and (–)‐cytisine starts with Matteson homologations for the construction of a chiral C3‐building block. Conversion of the C3‐building block into a dihydropyridone is achieved by straightforward functional group interconversions and ring closing metathesis. After bromination, this central building block was diastereospecifically converted into cytisine in five steps.
Azide–Enolate 1,3‐Dipolar Cycloaddition as an Efficient Approach for the Synthesis of 1,5‐Disubstituted 1,2,3‐Triazoles from Alkyl/Aryl Azides and β‐Ketophosphonates
Authors: González‐Calderón Davir , Fuentes‐Benítes Aydeé , Díaz‐Torres Eduardo , González‐González Carlos A. , González‐Romero Carlos 
Published: January 2016

AbstractA simple procedure to prepare 1,5‐disubstituted 1,2,3‐triazoles efficiently from alkyl/aryl azides and β‐ketophosphonates in the presence of KOH by an azide–enolate 1,3‐dipolar cycloaddition in good yields was developed.
Bridging Chiral Calix[4]arenes: Description, Optical Resolution, and Absolute Configuration Determination
Authors: An Feng‐Jing , Xu Wen‐Qiang , Zheng Shuang , Ma Shi‐Kun , Li Shao‐Yong , Wang Run‐Ling , Liu Jun‐Min 
Published: January 2016

AbstractA new chiral calix[4]arene constructed from asymmetric substitution on bridging methylenes, phenyl rings, and (or) oxygen atoms was tentatively named as “bridging chiral” calix[4]arene that have point chirality on its substituted bridging methylene. A new approach to enantiopure bridging chiral calix[4]arenes through optical resolution is presented for the first time. As a result, a pair of enantiopure bridging chiral calix[4]arene carboxylic acids monobridge‐substituted with an equatorial N,N′‐dimethylformamidyl group (4a and 4b) were easily prepared by the optical resolution of their racemate with chiral auxiliary (S)‐Binol. The absolute configurations of the enantiomers were determined by X‐ray crystallographic analysis.
An Efficient and Tunable Route to Bis(1,2,3‐triazol‐1‐yl)methane‐Based Nitrogen Compounds
Authors: Castro‐Osma José A. , Lara‐Sanchez Agustín , Otero Antonio , Rodríguez Ana M. , de la Torre María C. , Sierra Miguel A. 
Published: January 2016

AbstractA new and easy route to prepare “a la carte” bis(1,2,3‐triazol‐1‐yl)methane compounds, namely bmtzm (1), bptzm (2), bttzm (3), bmtzpm (4), bptzpm (5), bttzpm (6), bmtzom (7), bptzom (8) and bttzom (9), with different functional groups is reported. The compounds were prepared by reaction between readily accessible alkynes and geminal diazides in a double Cu‐catalyzed azide‐alkyne cycloaddition (CuAAC) reaction. These materials were used as starting materials for the synthesis of more elaborate compounds. Thus, the preparation of new bis(1,2,3‐triazol‐1‐yl)methane‐based heteroscorpionate neutral precursors pbptztamH (10), pbttztamH (11), (S)‐mbptzamH (12) and (S)‐mbttzamH (13) and a dinuclear zinc complex, [Zn{pbptztam}Et]2 (14), was achieved. The structures of the compounds were determined by spectroscopic methods, and the X‐ray crystal structures of compounds 2, 3, 7, 8, 9 and 14 were established.
An Efficient Approach to the Total Synthesis of Ammosamide B
Authors: Yang Sheng‐Wei , Wang Chun‐Meng , Tang Kai‐Xiang , Wang Jin‐Xin , Sun Li‐Ping 
Published: January 2016

AbstractA new approach for the total synthesis of ammosamide B was realized. The strategy is based on an intermolecular Pd‐catalyzed N‐arylation of 4‐chloro‐1‐methylindoline‐2,3‐dione (2), which enables construction of the key pyrroloquinoline skeleton precursor 6 within three steps in an overall yield of 80 %. The ammosamide B total synthesis is achieved in 12 simple transformations by starting from a commercially available starting material and proceeds with an overall yield of 23 %. Additionally, key precursor 6 represents an important intermediate in the synthesis of other pyrroloquinoline‐containing natural products.