bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liquid‐Crystalline Ordering as a Concept in Materials Science: From Semiconductors to Stimuli‐Responsive Devices
Authors: Fleischmann Eva‐Kristina , Zentel Rudolf 
Published: July 2013

AbstractWhile the unique optical properties of liquid crystals (LCs) are already well exploited for flat‐panel displays, their intrinsic ability to self‐organize into ordered mesophases, which are intermediate states between crystal and liquid, gives rise to a broad variety of additional applications. The high degree of molecular order, the possibility for large scale orientation, and the structural motif of the aromatic subunits recommend liquid‐crystalline materials as organic semiconductors, which are solvent‐processable and can easily be deposited on a substrate. The anisotropy of liquid crystals can further cause a stimuli‐responsive macroscopic shape change of cross‐linked polymer networks, which act as reversibly contracting artificial muscles. After illustrating the concept of liquid‐crystalline order in this Review, emphasis will be placed on synthetic strategies for novel classes of LC materials, and the design and fabrication of active devices.
Polyurethanes: Versatile Materials and Sustainable Problem Solvers for Today’s Challenges
Authors: Engels Hans‐Wilhelm , Pirkl Hans‐Georg , Albers Reinhard , Albach Rolf W. , Krause Jens , Hoffmann Andreas , Casselmann Holger , Dormish Jeff 
Published: July 2013

AbstractPolyurethanes are the only class of polymers that display thermoplastic, elastomeric, and thermoset behavior depending on their chemical and morphological makeup. In addition to compact polyurethanes, foamed variations in particular are very widespread, and they achieve their targeted properties at very low weights. The simple production of sandwich structures and material composites in a single processing step is a key advantage of polyurethane technology. The requirement of energy and resource efficiency increasingly demands lightweight structures. Polyurethanes can serve this requirement by acting as matrix materials or as flexible adhesives for composites. Polyurethanes are indispensable when it comes to high‐quality decorative coatings or maintaining the value of numerous objects. They are extremely adaptable and sustainable problem solvers for today’s challenges facing our society, all of which impose special demands on materials.
Crystallization of isotactic polypropylene inside dense networks of carbon nanofillers
Authors: Chen Jing‐Bin , Xu Jia‐Zhuang , Pang Huan , Zhong Gan‐Ji , Xu Ling , Tang Hu , Tang Jian‐Hua , Li Zhong‐Ming 
Published: July 2013

ABSTRACTIn this study, we performed the crystallization of carbon nanotube (CNT)/isotactic polypropylene (iPP) and graphene nanosheet (GNS)/iPP composites with very high nanofiller loadings; these are frequently used in polymer composites for electromagnetic interference shielding and thermal conductivity. Rheology testing indicated that both the high‐loading CNTs and GNSs formed dense networks in the iPP matrix, and transmission electron microscopy showed that their connection types were completely different: the CNTs contacted one another in a dot‐to‐dot manner, whereas the GNSs linked reciprocally in a plane‐to‐plane manner. The carbon nanofiller networks brought about two opposite effects on iPP crystallization: a nucleation effect and a confinement effect. The CNT network showed a stronger nucleation effect; however, the CNT network also revealed a more powerful confinement effect because the CNT network was denser than the GNS network. With increasing content of the carbon nanofillers, the crystallization rates of both the CNT and GNS composites first increased, then decreased, and showed a very high saturation concentration at 50 wt %; this resulted from the competitive relationship between the nucleation effect and confinement effect. The crystallization was facilitated when the carbon nanofiller concentration was below saturation, where the nucleation effect invariably played a dominant role. Although the crystallization was depressed when the carbon nanofiller concentration was above saturation, the nucleation effect was subdued, and the confinement effect was extensive. Compared to the GNS/iPP composites, the CNT/iPP composites showed a more depressed crystallization. The suppression mechanism is discussed with consideration of the local topological structure constructed by those two carbon nanofillers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39505.
Morphology, polymorphism, and metal ion adsorption studies of electrospun nanofibers based on PVDF and organically modified layered double hydroxide
Authors: Birajdar Mallinath S. , Wanjale Santosh D. , Lonkar Sunil P. 
Published: July 2013

ABSTRACTNonwoven nanofiber mats of polyvinylidene fluoride (PVDF) with modified layered double hydroxide (MLDH) were prepared by electrospinning. The fiber morphology was studied using scanning electron microscopy. X‐ray diffraction and FTIR spectroscopy was used to characterize the polymorphism in electrospun mats. Fibers of diameter in the range 80–800 nm with beads of about 2–3 µm size were observed for pure PVDF, while in case of PVDF/MLDH nanocomposites the number and size of beads were found to be significantly reduced. Uniform and fine nanofibers were obtained at lower content of MLDH, but slightly rough surface was seen for higher content. FTIR and X‐ray diffraction patterns signify various crystalline forms of electrospun PVDF. The content of polar β‐crystalline phase of PVDF, which exhibit piezo and ferroelectric properties was found to be enhanced significantly due to reinforcement of MLDH. Use of these nanofiber mats for heavy metal Cu (II) removal was explored. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4508–4515, 2013
Pathways for biomass‐derived lignin to hydrocarbon fuels
Authors: Laskar Dhrubojyoti D. , Yang Bin , Wang Huamin , Lee John 
Published: July 2013

AbstractProduction of hydrocarbon fuel from biomass‐derived lignin sources with current vision of biorefinery infrastructure would significantly improve the total carbon use in biomass and make biomass conversion more economically viable. Thus, developing specialty and commodity products from biomass derived‐lignin has been an important industrial and scientific endeavor for several decades. However, deconstruction of lignin's complex polymeric framework into low molecular weight reactive moieties amenable for deoxygenation and subsequent processing into hydrocarbons has proven challenging. This review offers a comprehensive outlook on the existing body of work that has been devoted to catalytic processing of lignin derivatives into hydrocarbon fuels, focusing on: (i) the intrinsic complexity and characteristic structural features of biomass‐derived lignin; (ii) existing processing technologies for the isolation and depolymerization of bulk lignin (including detailed mechanistic considerations); (iii) approaches aimed at significantly improving the yields of depolymerized lignin species amenable to catalytic upgrading; and (iv) catalytic upgrading, using aqueous phase processes for transforming depolymerized lignin to hydrocarbon derivatives. Technical barriers and challenges to the valorization of lignin are highlighted throughout. The central goal of this review is to present an array of strategies that have been reported to obtain lignin, deconstruct it to reactive intermediates, and reduce its substantial oxygen content to yield hydrocarbon liquids. In this regard, reaction networks with reference to studies of lignin model compounds are exclusively surveyed. Special attention is paid to catalytic hydrodeoxygenation, hydrogenolyis, and hydrogenation. Finally, this review addresses important features of lignin that are vital to economic success of hydrocarbon production. Published in 2013 by John Wiley & Sons, Ltd
Rural African renewable fuels and fridges: cassava waste for bioethanol, with stillage mixed with manure for biogas digestion for application with dual‐fuel absorption refrigeration
Authors: McHenry Mark P. , Doepel David , de Boer Karne 
Published: July 2013

AbstractThe growth and processing of cassava (Manihot esculenta) in Africa produces a range of waste streams which are proving problematic due to their current mismanagement. Although a range of technical solutions exists to convert these waste streams into valuable products, there has been very little progress made in applying these solutions. This review provides a broad picture of the cassava waste issue in the context of African agriculture and bioprocessing. As an outcome of the review process the authors propose a simple and scalable two‐step process that biologically converts the waste streams into valuable products. The first step in the process is fermentation and distillation of the cassava waste to produce ethanol. The second step is the anaerobic digestion of the fermentation byproducts with other waste streams, including animal manure and human excrement, to produce biogas and biological fertilizers. Despite the scalability of this system, the focus of this review is the development of a conceptual system for rural smallholders to achieve multiple beneficial outcomes including treatment of multiple troublesome waste streams, production of a liquid biofuel, the provision of refrigeration through biogas powered absorption chillers, and the co‐production of organic fertilizers. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd
True Context‐dependent Preferences? The Causes of Market‐dependent Valuations
Authors: Mazar Nina , Koszegi Botond , Ariely Dan 
Published: July 2013

ABSTRACTA central assumption of neoclassical economics is that reservation prices for familiar products express people's true preferences for these products; that is, they represent the total benefit that a good confers to the consumers and are, thus, independent of actual prices in the market. Nevertheless, a vast amount of research has shown that valuations can be sensitive to other salient prices, particularly when individuals are explicitly anchored on them. In this paper, the authors extend previous research on single‐price anchoring and study the sensitivity of valuations to the distribution of prices found for a product in the market. In addition, they examine its possible causes. They find that market‐dependent valuations cannot be fully explained by rational inferences consumers draw about a product's value and are unlikely to be fully explained by true market‐dependent preferences. Rather, the market dependence of valuations likely reflects consumers' focus on something other than the total benefit that the product confers to them. Furthermore, this paper shows that market‐dependent valuations persist when – as in many real‐life settings – individuals make repeated purchase decisions over time and infer the distribution of the product's prices from their market experience. Finally, the authors consider the implications of their findings for marketers and consumers. Copyright © 2013 John Wiley & Sons, Ltd.
Evaluation of anger management groups in a high‐security hospital
Authors: Wilson Claire , Gandolfi Stacy , Dudley Alison , Thomas Brian , Tapp James , Moore Estelle 
Published: July 2013

ABSTRACTBackgroundAnger management programmes for offenders typically aim to improve the management of emotion associated with aggressive and antisocial behaviour. Such programmes have been quite extensively evaluated in prison and probation settings, but there is less published research in forensic mental health settings.AimThis study aimed to evaluate anger management groups in a high‐security hospital.MethodEighty‐six patients were referred for a 20‐session anger management intervention. Outcomes were self‐reported experiences of anger and changes in institutionally documented incidents of aggression. Incident rates were retrospectively reviewed for all group graduates, where data were available, including a comparison group of graduates who acted as their own controls.ResultsGroup graduates reported sustained reductions in feelings of anger and positive changes in their use of aggression in reaction to provocation. Some reduction in incidents of physical aggression was noted when group completers were compared with non‐completers. Incidents of verbal aggression were observed to increase for graduates. There was also a trend towards improvement when treated men were compared with men on the waiting list.ConclusionsOur findings contribute to the growing evidence for anger management groups for aggressive men, although the low‐base rate of incidents, typical of such a containing and therapeutic hospital setting, rendered the analysis of behavioural outcomes difficult.Implications for practice and researchAnger management sessions for male forensic psychiatric patients can be effective in reducing incidents of physical aggression in response to provocation. Evaluation of treatments for anger is particularly difficult in secure and protective settings, where the aim is to keep incidents of actual physical aggression to a minimum. Further research of this kind is needed to test the value of self‐reported reduction in angry feelings as an indicator of clinically useful progress. Copyright © 2013 John Wiley & Sons, Ltd.
Novel Glutaric Acid Cocrystal Formation via Cogrinding and Solution Crystallization
Authors: Bian L. , Zhao H. , Hao H. , Yin Q. , Wu S. , Gong J. , Dong W. 
Published: July 2013

AbstractAn efficient and reliable approach to discover new pharmaceutical cocrystals in the early development stage is proposed and used to develop cocrystals of piracetam with some aliphatic diacids. A 1:1 cocrystal of piracetam and glutaric acid was screened by a mechanochemical method and identified by powder X‐ray diffraction and differential scanning calorimetry. Followed by solution crystallization, this cocrystal was reproduced. To better understand the mechanism of cocrystal formation in solution crystallization, process analytical technologies including focused beam reflectance measurement, attenuated total reflectance‐Fourier transform infrared, and particle vision measurement were applied to investigate the cocrystallization process of piracetam with glutaric acid. The mechanism of cocrystal formation during solution‐mediated phase transformation is discussed in detail.
Self‐Fluidization in an Indirectly Heated Calciner
Authors: Hoeftberger D. , Karl J. 
Published: July 2013

AbstractA promising way to reduce CO2 emissions of fossil‐fired power plants is the carbonate looping process with the reversible carbonation‐calcination reaction of limestone. The focus is on the gas release in an indirectly heat pipe‐heated calciner. Experiments in an electrically heated lab‐scale batch calciner demonstrated that transition from a fixed bed to a bubbling fluidized bed is possible without an external fluidization agent only by heating up limestone. Several indirectly heated calciner concepts are presented.
Single‐Particle Spectroscopy on Large SAPO‐34 Crystals at Work: Methanol‐to‐Olefin versus Ethanol‐to‐Olefin Processes
Authors: Qian Qingyun , Ruiz‐Martínez Javier , Mokhtar Mohamed , Asiri Abdullah M. , Al‐Thabaiti Shaeel A. , Basahel Suliman N. , van der Bij Hendrik E. , Kornatowski Jan , Weckhuysen Bert M. 
Published: July 2013

AbstractThe formation of hydrocarbon pool (HCP) species during methanol‐to‐olefin (MTO) and ethanol‐to‐olefin (ETO) processes have been studied on individual micron‐sized SAPO‐34 crystals with a combination of in situ UV/Vis, confocal fluorescence, and synchrotron‐based IR microspectroscopic techniques. With in situ UV/Vis microspectroscopy, the intensity changes of the λ=400 nm absorption band, ascribed to polyalkylated benzene (PAB) carbocations, have been monitored and fitted with a first‐order kinetics at low reaction temperatures. The calculated activation energy (Ea) for MTO, approximately 98 kJ mol−1, shows a strong correlation with the theoretical values for the methylation of aromatics. This provides evidence that methylation reactions are the rate‐determining steps for the formation of PAB. In contrast for ETO, the Ea value is approximately 60 kJ mol−1, which is comparable to the Ea values for the condensation of light olefins into aromatics. Confocal fluorescence microscopy demonstrates that during MTO the formation of the initial HCP species are concentrated in the outer rim of the SAPO‐34 crystal when the reaction temperature is at 600 K or lower, whereas larger HCP species are gradually formed inwards the crystal at higher temperatures. In the case of ETO, the observed egg‐white distribution of HCP at 509 K suggests that the ETO process is kinetically controlled, whereas the square‐shaped HCP distribution at 650 K is indicative of a diffusion‐controlled process. Finally, synchrotron‐based IR microspectroscopy revealed a higher degree of alkylation for aromatics for MTO as compared to ETO, whereas high reaction temperatures favor dealkylation processes for both the MTO and ETO processes.
Validity of Inorganic Nanosheets as an Efficient Planar Substituent To Enhance the Enantioselectivity of Transition‐Metal‐Catalyzed Asymmetric Synthesis
Authors: Zhao Li‐Wei , Shi Hui‐Min , An Zhe , Wang Jiu‐Zhao , He Jing 
Published: July 2013

AbstractEffectively enhancing the enantioselectivity is a persistent challenge in heterogeneous asymmetric catalysis. Here, the validity of a layered double hydroxides (LDH) nanosheet as an efficient planar substituent to enhance the enantioselectivity has been investigated theoretically; first in vanadium‐catalyzed asymmetric epoxidation of allylic alcohols, and then in zinc‐catalyzed direct asymmetric aldol addition. The computational predication is further confirmed experimentally in zinc‐catalyzed direct asymmetric aldol addition by controlling the location of catalytic sites.
Porous Nitrogen‐Doped Carbon Nanotubes Derived from Tubular Polypyrrole for Energy‐Storage Applications
Authors: Xu Guiyin , Ding Bing , Nie Ping , Shen Laifa , Wang Jie , Zhang Xiaogang 
Published: July 2013

AbstractPorous nitrogen‐doped carbon nanotubes (PNCNTs) with a high specific surface area (1765 m2 g−1) and a large pore volume (1.28 cm3 g−1) have been synthesized from a tubular polypyrrole (T‐PPY). The inner diameter and wall thickness of the PNCNTs are about 55 nm and 22 nm, respectively. This material shows extremely promising properties for both supercapacitors and for encapsulating sulfur as a superior cathode material for high‐performance lithium–sulfur (Li‐S) batteries. At a current density of 0.5 A g−1, PNCNT presents a high specific capacitance of 210 F g−1, as well as excellent cycling stability at a current density of 2 A g−1. When the S/PNCNT composite was tested as the cathode material for Li‐S batteries, the initial discharge capacity was 1341 mAh g−1 at a current rate of 1 C and, even after 50 cycles at the same rate, the high reversible capacity was retained at 933 mAh g−1. The promising electrochemical energy‐storage performance of the PNCNTs can be attributed to their excellent conductivity, large surface area, nitrogen doping, and unique pore‐size distribution.
Molecular and Electronic‐Structure Basis of the Ambipolar Behavior of Naphthalimide–Terthiophene Derivatives: Implementation in Organic Field‐Effect Transistors
Authors: Ponce Ortiz Rocío , Herrera Helena , Mancheño María J. , Seoane Carlos , Segura José L. , Mayorga Burrezo Paula , Casado Juan , López Navarrete J. Teodomiro , Facchetti Antonio , Marks Tobin J. 
Published: July 2013

AbstractA new family of naphthalimide‐fused thienopyrazine derivatives for ambipolar charge transport in organic field‐effect transistors is presented. Their electronic and molecular structures were elucidated through optical and vibrational spectroscopy aided by DFT calculations. The results indicate that these compounds have completely planar molecular skeletons which promote good film crystallinity and low reorganization energies for both electron and hole transport. Their performance in organic field‐effect transistors is compared with twisted and planar naphthaleneamidine monoimide‐fused terthiophenes in order to understand the origin of ambipolarity in this new series of molecular semiconductors.
Chemoselectivity Control: Gold(I)‐Catalyzed Synthesis of 6,7‐Dihydrobenzofuran‐4(5H)‐ones and Benzofurans from 1‐(Alkynyl)‐7‐oxabicyclo[4.1.0]heptan‐2‐ones
Authors: Wang Tao , Shi Shuai , Vilhelmsen Mie Højer , Zhang Tuo , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K. 
Published: July 2013

AbstractNew and chemoselective gold(I)‐catalyzed transformations of 1‐(arylethynyl)‐7‐oxabicyclo[4.1.0]‐ heptan‐2‐ones were developed. Two completely different products—6,7‐dihydrobenzofuran‐4(5H)‐ones and benzofurans—could be obtained from the same starting material. The selectivity is determined by the ligand of the gold catalyst: triphenylphosphine delivers 6,7‐dihydrobenzofuran‐4(5H)‐ones, and 1,3‐bis(diisopropylphenyl)imidazol‐2‐ylidene leads to benzofurans. Eleven examples of each case are provided. The mechanistic suggestions for the pathways to both product types are supported by isotope labeling experiments.
Diagnostic Accuracy and Cost‐Effectiveness of a Pocket‐Sized Transthoracic Echocardiographic Imaging Device
Authors: Kitada Ryoko , Fukuda Shota , Watanabe Hiroyuki , Oe Hiroki , Abe Yukio , Yoshiyama Minoru , Song Jong‐Min , Sitges Marta , Shiota Takahiro , Ito Hiroshi , Yoshikawa Junichi 
Published: July 2013

AbstractBackgroundThe recently introduced pocket‐sized portable transthoracic echocardiography (pTTE) is accurate for measurement of cardiac chamber size and function as well as for assessment of valvular regurgitation. This study aimed to compare the diagnostic accuracy of the pocket‐sized pTTE with the standard TTE (sTTE) and assess its cost‐effectiveness.HypothesisThe use of pocket‐sized pTTE, as an initial screening tool, may be feasible, accurate and cost‐effective in the diagnostic strategy of cardiac abnormalities.MethodsThe study subjects were 200 patients scheduled for sTTE and an electrocardiogram (ECG). Each patient underwent pTTE examination with the Vscan (GE Medical Systems, Milwaukee, WI) immediately after sTTE. The findings of pTTE and the ECG were compared with the results of sTTE. Cost‐effectiveness was calculated.ResultsThere was a strong agreement in the detection of abnormal findings between pTTE and sTTE (agreement = 90%), whereas the agreement between the ECG and sTTE was 65%. When pTTE or the ECG was used as an initial screening tool prior to sTTE, similar cost reduction was obtained (approximately 30%) by reducing the number of referrals for sTTE. However, the negative predictive value of a diagnostic strategy with pTTE (92%) was superior to that with an ECG (67%).ConclusionsThis study demonstrates that the pocket‐sized pTTE provides accurate detection of cardiac structural and functional abnormalities beyond the ECG. In addition, the use of pTTE as an initial screening tool prior to sTTE is cost‐effective, suggesting that the pocket‐sized pTTE is poised to alter the current diagnostic strategy in clinical practice.