bluuebunny/crossref_metadata_2025_split huggingface dataset:
Palladium‐Catalyzed Enantioselective CH Arylation for the Synthesis of P‐Stereogenic Compounds
Authors: Lin Zi‐Qi , Wang Wei‐Zhen , Yan Shao‐Bai , Duan Wei‐Liang 
Published: April 2015

AbstractA palladium‐catalyzed enantioselective CH arylation of N‐(o‐bromoaryl)‐diarylphosphinic amides is described for the synthesis of phosphorus compounds bearing a P‐stereogenic center. The method provides good enantioselectivities and high yields. The products were readily transformed into P‐chiral biphenyl monophosphine ligands.
Synthesis, Structure, and Air‐stable N‐type Field‐Effect Transistor Behaviors of Functionalized Octaazanonacene‐8,19‐dione
Authors: Wang Chengyuan , Zhang Jing , Long Guankui , Aratani Naoki , Yamada Hiroko , Zhao Yang , Zhang Qichun 
Published: April 2015

AbstractIncreasing the length of N‐heteroacenes or their analogues is highly desirable because such materials could have great potential applications in organic electronics. In this report, the large π‐conjugated N‐heteroquinone 6,10,17,21‐tetra‐((triisopropylsilyl)ethynyl)‐5,7,9,11,16,18,20,22‐octaazanonacene‐8,19‐dione (OANQ) has been synthesized and characterized. The as‐prepared OANQ shows high stability under ambient conditions and has a particularly low LUMO level, which leads to it being a promising candidate for air‐stable n‐type field‐effect transistors (FETs). In fact, FET devices based on OANQ single crystals have been fabricated and an electron mobility of up to 0.2 cm2 V−1 s−1 under ambient conditions is reported. More importantly, no obvious degradation was observed even after one month. Theoretical calculations based on the single crystal are consistent with the measured mobility.
Sol Processing of Conjugated Carbon Nitride Powders for Thin‐Film Fabrication
Authors: Zhang Jinshui , Zhang Mingwen , Lin Lihua , Wang Xinchen 
Published: April 2015

AbstractThe chemical protonation of graphitic carbon nitride (CN) solids with strong oxidizing acids, for example HNO3, is demonstrated as an efficient pathway for the sol processing of a stable CN colloidal suspension, which can be translated into thin films by dip/disperse‐coating techniques. The unique features of CN colloids, such as the polymeric matrix and the reversible hydrogen bonding, result in the thin‐film electrodes derived from the sol solution exhibiting a high mechanical stability with improved conductivity for charge transport, and thus show a remarkably enhanced photo‐electrochemical performance. The polymer system can in principle be broadly tuned by hybridization with desired functionalities, thus paving the way for the application of CN for specific tasks, as exemplified here by coupling with carbon nanotubes.
Highly Enantioselective Transfer Hydrogenation of Ketones with Chiral (NH)2P2 Macrocyclic Iron(II) Complexes
Authors: Bigler Raphael , Huber Raffael , Mezzetti Antonio 
Published: April 2015

AbstractBis(isonitrile) iron(II) complexes bearing a C2‐symmetric diamino (NH)2P2 macrocyclic ligand efficiently catalyze the hydrogenation of polar bonds of a broad scope of substrates (ketones, enones, and imines) in high yield (up to 99.5 %), excellent enantioselectivity (up to 99 % ee), and with low catalyst loading (generally 0.1 mol %). The catalyst can be easily tuned by modifying the substituents of the isonitrile ligand.
Formation of Tri‐ and Tetranuclear Titanacycles through Decamethyltitanocene‐Mediated Intermolecular C–C Coupling of Dinitriles
Authors: Becker Lisanne , Arndt Perdita , Spannenberg Anke , Jiao Haijun , Rosenthal Uwe 
Published: April 2015

AbstractThe reactions of [Cp*2Ti(η2‐Me3SiC2SiMe3)] (Cp*=η5‐pentamethylcyclopentadienyl) with various dicyano compounds were investigated. Nitrile–nitrile CC couplings result in multinuclear complexes owing to the bifunctionality of the substrates. Applying 1,3‐ or 1,4‐dicyanobenzene led to tri‐ and tetranuclear complexes of the rare 1‐metalla‐2,5‐diaza‐cyclopenta‐2,4‐dienes. These are potential catalysts and were tested in the ring‐opening polymerization of ε‐caprolactone. The reaction with adiponitrile as alkyl dinitrile afforded a trinuclear 1‐metalla‐2,5‐diaza‐cyclopent‐3‐ene through additional protonation of the nitrogen atoms. The structure and bonding of the products were investigated by X‐ray crystallography and DFT analysis to understand the molecular organization in the macrocycles.
Microscale Crystals of Cytochrome c and Calixarene on Electrodes: Interprotein Electron Transfer between Defined Sites
Authors: McGovern Róise E. , Feifel Sven C. , Lisdat Fred , Crowley Peter B. 
Published: April 2015

AbstractThe assembly of redox proteins on electrodes is an important step in biosensor development. Recently, p‐sulfonato‐calix[4]arene was shown to act as “molecular glue” for the assembly and crystallization of cytochrome c (cyt c). Electrochemical data are presented for microscale cyt c–calixarene crystals grown on self‐assembled monolayers (SAM)‐modified Au electrodes. The crystals were characterized by cyclic voltammetry and exceptionally high concentrations of electroactive cyt c were obtained. The peak currents were found to increase linearly with the square root of the scan rate, thus allowing an evaluation of the rate constant for electron self‐exchange. This study revealed high electroactivity accompanied by fast interprotein electron transfer in crystals, which may have implications for the construction of novel bioelectronic devices.
Flow pattern transition, frictional pressure drop, and holdup of gas non‐Newtonian fluid flow in helical tube
Authors: Thandlam Anil Kumar , Mandal Tapas Kumar , Majumder Subrata Kumar 
Published: April 2015

AbstractAn investigation on flow pattern, pressure drop, and holdup of cocurrent upward two‐phase flow in a vertical helical coil tube has been carried out with Newtonian and non‐Newtonian fluids. The flow patterns observed in the present study are divided into three main regimes, i.e. plug flow, slug flow, and stratified flow. Lockhart–Martinelli parameter (X) was used to predict the friction factor and frictional pressure drop of two‐phase flow. Correlations for the frictional pressure drop were developed to interpret the observed flow patterns with various operating variables. The effect of geometrical parameters on flow pattern, pressure drop, and holdup are enunciated. Based on the experimental data, a correlation was proposed to predict the flow transitions of flow patterns (i.e. plug–slug flow and slug–stratified flow) by dimensional analysis. Probabilistic neural network model has also been developed to predict the flow patterns of two‐phase flow. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd.
The application of polyethyleneimine draw solution in a combined forward osmosis/nanofiltration system
Authors: Jun Byung‐Moon , Nguyen Thi Phuong Nga , Ahn Soo‐Hyun , Kim In‐Chul , Kwon Young‐Nam 
Published: April 2015

ABSTRACTThe objective of this study is to investigate the effect of solution chemistry of branched polyethyleneimine (PEI) draw solute and to evaluate the PEI draw solute in a combined forward osmosis (FO)/nanofiltration (NF) system. Pure water was extracted from feed solution using the FO process, and the separation of pure water was achieved by the NF process. Lower molecular weight PEI showed higher water flux than higher molecular weight PEI, due to the lower internal concentration polarization caused by a higher diffusion rate and the easy permeation of pure water by lower viscosity of the draw solution (DS). The FO water flux was determined by the osmotic pressure induced by protonation/deprotonation of PEI, and the reverse draw solute flux was determined by the combination of PEI size due to the speciation and electrostatic interaction between the membrane and PEI. This study shows that the Js/Jw value of PEI at pH 7 was smaller than those of sodium chloride and magnesium sulfate. The recovery of PEI DS using NF has a higher value (99.4%) than of sodium chloride (20.6%) and magnesium sulfate (97.0%); this means that PEI would be a promising draw solute in an FO–NF combined system for the saline water desalination. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42198.
Exploration of deep eutectic solvent‐based mesoporous silica spheres as high‐performance size exclusion chromatography packing materials
Authors: Tang Baokun , Row Kyung Ho 
Published: April 2015

ABSTRACTCholine chloride (ChCl) with three alcohol‐based deep eutectic solvents (DESs) was applied as a new type of green solvent for the modification of mesoporous silica spheres. The mesoporous silica spheres were characterized by field emission scanning electron microscopy and Brunauer–Emmett–Teller surface area analysis. Many uniform and mesoporous silica spheres were obtained with a ChCl–1,2‐butanediol DES as a reactant. The DES‐modified mesoporous silica spheres were used for the adsorption of polysaccharides (alginic acid, fucoidan, and laminarin). The adsorption results show that the ChCl–1,2‐butanediol DES‐based silica spheres had stable interactions with the target compounds. A comparison of the three sorbents as size exclusion chromatography packing materials showed that the ChCl–1,2‐butanediol DES‐based silica spheres produced good resolution of the three test polysaccharides and exhibited the best separation capability. This was attributed to the uniform mesoporous structure of the ChCl–1,2‐butanediol DES‐based silica spheres. Therefore, more DESs should be applied to the preparation of mesoporous silica spheres in future studies. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42203.
Carbohydrate crosslinked biocompatible polyurethanes: Synthesis, characterization, and drug delivery studies
Authors: Solanki Archana Ritesh , Kamath Bolavinayak V. , Thakore Sonal 
Published: April 2015

ABSTRACTA series of novel polyurethanes (PUs) with carbohydrate crosslinkers was synthesized. The drug loading and release kinetics were studied by using lamotrigine as a model drug. The polymers were designed in such a way that the drug release was tailored by differences in the stoichiometry of polymers. All the PUs were characterized for thermal and morphological properties by using differential scanning calorimetry and thermogravimetric analysis and scanning electron microscope, respectively. The encapsulation of drug inside PU matrix was confirmed via Fourier transform‐infrared (FT‐IR) spectra and scanning electron microscope. The kinetics and release mechanisms were observed to be a function of stoichiometric parameters such as type of crosslinker, polyol/crosslinker ratio and polyol/chain extender ratio. All the PUs were observed to be non‐cytotoxic in normal lung cell line L132. The synthesized PUs exhibited good mechanical strength, tunable release rates and biocompatibility that can be utilized in biomedical applications like wound dressing, biomedical implants, and drug delivery carriers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42223.
Ansatz von Streuungsfaktoren bei statischen und dynamischen Pfahlprobebelastungen
Authors: Moormann Christian 
Published: April 2015

AbstractBei der Ermittlung der Bemessungswerte von Pfahlwiderständen aus den Ergebnissen von statischen und dynamischen Pfahlprobebelastungen sind die Versuchs‐ bzw. Messwerte Rc;m der Pfahltragfähigkeit zunächst mittels Streuungsfaktoren ξ abzumindern und damit in charakteristische Pfahlwiderstände Rc;k umzuwandeln. Mit den Streuungsfaktoren soll der Einfluss der räumlichen Variabilität der Baugrundverhältnisse, aber auch der Unschärfen, die sich aus der Durchführung und der Auswertung der Pfahlprobebelastungen ergeben, bei der Ableitung des charakteristischen Pfahlwiderstandes aus den Messwerten einer einzelnen oder einer begrenzten Anzahl von Probebelastungen berücksichtigt werden. Eine bewertende Analyse zeigt, dass die im Handbuch Eurocode 7, Band 1, enthaltenen Regelungen zur Ermittlung der Streuungsfaktoren insbesondere im Hinblick auf die alleinige Abhängigkeit der Streuungsfaktoren von der Anzahl der durchgeführten Probebelastungen Schwächen aufweisen. Diesbezüglich werden Ansätze für eine Fortschreibung der Regelungen erörtert. Darüber hinaus wird ein Vorschlag für den Ansatz reduzierter ξ‐Werte für den Sonderfall, dass an allen Pfählen einer Pfahlgründung eine dynamische Probebelastung ausgeführt wird (“n = n”), vorgestellt.Approach to the correlation factors for static and dynamic pile load testsIn determining the design values of a pile resistance from the results of static and dynamic pile load testing the measured values Rc;m of the pile capacity have to be initially mitigated by correlation factors ξ to derive the characteristic pile resistance Rc;k. With the correlations factors the influence of the spatial variability of the subsoil, but also of the uncertainties arising from the execution and evaluation of the pile load tests on the derivation of the characteristic pile resistance from the measured values of a single or limited number of test loads is taken into account. An analysis of the existing approach implemented in handbook Eurocode 7, Volume 1, indicates shortcomings particularly with respect to the sole dependency of the correlation factors on the number of performed load tests. In this regard approaches for an evolution of the present regulations are discussed. In addition, a proposal for reduced ξ‐values for the special case that dynamic load tests are executed at all piles of a pile foundation (“n = n”) is presented.
Neue Biegeschlankheitsdiagramme für Platten und Kragplatten nach EC2
Authors: Göttlich Peter , Fleckenstein Dirk 
Published: April 2015

AbstractAuf der Grundlage von [1, 2] wurden neue, sehr kompakte Biegeschlankheitsdiagramme jeweils für Einfeld‐ bzw. Durchlaufplatten und Kragplatten entwickelt. Die aus den Diagrammen ablesbare Biegeschlankheit gibt einen Richtwert vor, nach welchem ein Bauteil zu bemessen ist, damit der indirekte Nachweis der Verformung gemäß [3, 4] erfolgen kann. Im vorliegenden Aufsatz werden diese Diagramme vorgestellt und ihre einfache Anwendung beispielhaft dargestellt.New span to depth ratio diagrams for plates and cantilever plates according to EC2Efficient span‐to‐depth ratio diagrams, based on [1, 2], have been developed for simply supported, continuous, and cantilever plates. The values of the diagrams provide key parameters that can be used to analyze the plate elements and to complete indirect checks for deflection according to [3, 4]. The following article presents the diagrams and examples of how they can be used.
Hinweise zur Bemessung von Stahlkonsolen
Authors: Heidolf Thorsten , Schlegel Roger 
Published: April 2015

AbstractAn Stahlbetonkonstruktionen angeschraubte Stahlkonsolen stellen eine sofort belastbare Alternative zu Stahlbetonkonsolen dar, wobei der Schalungs‐ und ggf. Transportaufwand der Stahlbetonkonstruktion deutlich reduziert wird. Im Vergleich zu Stahlbetonkonsolen zeichnen sich die Stahlkonsolen im Allgemeinen durch signifikant geringere Abmessungen bzw. durch bis zu dreimal höhere Tragfähigkeiten aus.Die Bemessung derartiger Konstruktionen ist aufwendiger, da die verschiedenen Bauteile und deren Verbindungen nachzuweisen sind. Im vorliegenden Beitrag werden Hinweise insbesondere zu ausgewählten Nachweisen der Steg‐ und Gurtplatte gegeben und die getroffenen Annahmen mithilfe von FE‐Berechnungen verifiziert. Mit den vorgestellten Berechnungsmethoden können plastische Tragreserven genutzt und somit die Konstruktion wirtschaftlicher ausgelegt werden.Notes on the design of steel corbelsTo reinforced concrete structures bolted steel corbels are an alternative to reinforced concrete corbels. The formwork and any transportation costs of the reinforced concrete structure is thereby significantly reduced. Steel corbels are generally much smaller than reinforced concrete corbels or have up to three times higher load capacities.The design of such structures is, however, more complex. The different components and their connections are to be designed. In this paper notes are given to selected evidence of the web and flange plate. The assumptions made are verified by FE calculations. With the presented calculation methods plastic reserves can be used and hence the construction can be designed more efficiently.
Vereinfachung der Regeln zur Beschränkung der Verformungen nach EC2
Authors: Prietz Frank , Richtsteig Uwe 
Published: April 2015

AbstractEurocode 2 ermöglicht die Begrenzung der Verformungen auf zwei Wegen: einem Nachweis ohne und einem Nachweis mit direkter Berechnung der Verformungen. Beide Nachweise sind für den in der Praxis tätigen Ingenieur nicht zufriedenstellend.Der vorliegende Beitrag stellt einen Neuvorschlag für einen vereinfachten Nachweis der Verformungsbegrenzung vor, mit dem die erforderliche statische Höhe direkt berechnet werden kann. Ein Umweg über die Biegeschlankheit ist nicht mehr erforderlich.Simplified rules for deflection control according to EC2 – Proposal for slabs in buildingsEC2 offers two methods for the control of deflections: one without and one with calculating the deflections. Both are not satisfying for the day‐to‐day work of the practising engineers. In this contribution a proposal for a simplified deflection control is made which provides a direct calculation of the required depth.
Zur Dauerhaftigkeit von befahrenen Parkdecks in Regelwerken
Authors: Wiens Udo , Meyer Lars , Raupach Michael 
Published: April 2015

AbstractInnerhalb der beim DAfStb eingerichteten Ad‐hoc‐Gruppe “Dauerhaftigkeit von befahrenen Parkdecks” wurde vereinbart, eine Gesamtsystematik zu den Regelungen für die Dauerhaftigkeit von befahrenen Verkehrsflächen zu entwickeln, die aus einer Normenvorlage und aus Erläuterungen für das Heft 600 sowie Ausführungen für das DBV‐Merkblatt “Parkhäuser und Tiefgaragen” bestehen. Der Beitrag fasst die Ergebnisse der insgesamt vier Sitzungen der Ad‐hoc‐Gruppe zusammen, die im Laufe des Jahres 2015 veröffentlicht werden sollen.
pH‐responsive fluorescence chemical sensor constituted by conjugated polymers containing pyridine rings
Authors: Adachi Naoya , Kaneko Yuki , Sekiguchi Kazuki , Sugiyama Hiroki , Sugeno Masafumi 
Published: April 2015

AbstractPoly(p‐pyridinium phenylene ethynylene)s (PPyPE) functionalized with alternating donor–acceptor repeat units were synthesized by a Pd‐catalyzed Sonogashira coupling reaction between diethynyl monomer and di‐iodopyridine for use as a pH‐responsive fluorescence chemical sensor. The synthesized PPyPE, containing pyridine units, was characterized by FT‐IR, 1H and 13C NMR, UV–visible and fluorescence spectroscopies. We investigated the relationship between changes of optical properties and protonation/deprotonation of PPyPE containing pyridine units in solution. Addition of HCl decreased and red‐shifted the fluorescence intensity of the conjugated polymers that contained pyridine rings; fluorescence intensity of the polymers increased upon addition of NaOH solution. The synthesized PPyPE was found to be an effective and reusable chemical sensor for pH sensing. Copyright © 2015 John Wiley & Sons, Ltd.
Spectroscopic study on the interaction of bovine serum albumin with zinc(II) phthalocyanine
Authors: Li Yejing , Wang Yi , Wang Ao , Lu Shan , Zhou Lin , Zhou Jiahong , Lin Yun , Wei Shaohua 
Published: April 2015

AbstractThe interaction between the photosensitive antitumour drug, 2(3),9(10),16(17),23(24)‐tetra‐(((2‐aminoethylamino)methyl)phenoxy)phthalocyaninato‐zinc(II) (ZnPc) and bovine serum albumin (BSA) has been investigated using various spectroscopic methods. This work may provide some useful information for understanding the interaction mechanism of anticancer drug–albumin binding and gain insight into the biological activity and metabolism of the drug in blood. Based on analysis of the fluorescence spectra, ZnPc could quench the intrinsic fluorescence of BSA and the quenching mechanism was static by forming a ground state complex. Meanwhile, the Stern–Volmer quenching constant (KSV), binding constant (Kb), number of binding sites (n) and thermodynamic parameters were obtained. Results showed that the interaction of ZnPc with BSA occurred spontaneously via hydrogen bond and van der Waal's force. According to Foster's non‐radioactive energy transfer theory, the energy transfer from BSA to ZnPc occurred with high possibility. Synchronous fluorescence and circular dichroism (CD) spectra also demonstrated that ZnPc induced the secondary structure of and conformation changes in BSA, especially α helix. Copyright © 2015 John Wiley & Sons, Ltd.
Chemoradiation therapy for rectal cancer in the distal rectum followed by organ-sparing transanal endoscopic microsurgery (CARTS study)
Authors: Verseveld M , de Graaf E J R , Verhoef C , van Meerten E , Punt C J A , de Hingh I H J T , Nagtegaal I D , Nuyttens J J M E , Marijnen C A M , de Wilt J H W , Tanis P J , Bökkerink G M J , Rütten H , Doornebosch P G , Derksen E J , Dwarkasing R S , Cats A , M Tollenaar R A E , Rutten H J T , Leijtens J W A , van der Schelling G P , ten Tije A J , Lammering G , Beets G L , Aufenacker T J , Pronk A , Manusama E R , Hoff C , Bremers A J A 
Published: April 2015

Abstract

Background
This prospective multicentre study was performed to quantify the number of patients with minimal residual disease (ypT0–1) after neoadjuvant chemoradiotherapy and transanal endoscopic microsurgery (TEM) for rectal cancer.

Methods
Patients with clinically staged T1–3 N0 distal rectal cancer were treated with long-course chemoradiotherapy. Clinical response was evaluated 6–8 weeks later and TEM performed. Total mesorectal excision was advocated in patients with residual disease (ypT2 or more).

Results
The clinical stage was cT1 N0 in ten patients, cT2 N0 in 29 and cT3 N0 in 16 patients. Chemoradiotherapy-related complications of at least grade 3 occurred in 23 of 55 patients, with two deaths from toxicity, and two patients did not have TEM or major surgery. Among 47 patients who had TEM, ypT0–1 disease was found in 30, ypT0 N1 in one, ypT2 in 15 and ypT3 in one. Local recurrence developed in three of the nine patients with ypT2 tumours who declined further surgery. Postoperative complications grade I–IIIb occurred in 13 of 47 patients after TEM and in five of 12 after (completion) surgery. After a median follow-up of 17 months, four local recurrences had developed overall, three in patients with ypT2 and one with ypT1 disease.

Conclusion
TEM after chemoradiotherapy enabled organ preservation in one-half of the patients with rectal cancer.