bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ordered Mesoporous Materials
Authors: Kruk Michal 
Published: August 2017

Abstract
Mesoporous materials are classified as materials with pores of widths between 2 and 50 nm. These materials are important in separations, heterogeneous catalysis, and many other applications. Mesoporous materials are usually disordered at nanoscale, but their structurally well‐defined families emerged in 1990s and have gained prominence. Herein, ordered materials with mesopores templated by surfactant micelles are discussed, with the primary focus on those with silica‐based frameworks. Structures of representative ordered mesoporous silicas, including those with cylindrical and spherical mesopores, are presented in the context of families of surfactants (primarily cationic surfactants and poly(ethylene oxide)‐based nonionic surfactants) that are suitable for their synthesis. Selected mechanisms of formation of the materials are outlined. Different achievable framework compositions are briefly noted. Basic principles of the pore shape control based on surfactant packing considerations are introduced. Mechanisms of pore size control are discussed. In particular, the pore size adjustability through the selection of surfactants of different molecular sizes and the addition of micelle swelling agents (expanders) is reviewed, and ranges of achievable pore diameters are outlined. The pore size tuning based on the framework shrinkage upon surfactant removal is also noted. The pore accessibility and connectivity are delineated for both spherical and cylindrical mesopores, and the means of their control are outlined, noting also limitations in their applicability. While this chapter provides only a glimpse of a vast field of ordered mesoporous solids, it is meant to reflect some of the most important characteristics of the remarkable family of materials.
Macroporous Materials Synthesized by Colloidal Crystal Templating
Authors: Hu Jinbo , Stein Andreas 
Published: August 2017

Abstract

Colloidal crystal templating is a versatile approach to synthesize nanostructured porous materials with a wide variety of compositions. The resulting three‐dimensionally ordered macroporous (3
DOM
) or mesoporous (3
DOm
) materials exhibit periodic pore structure with pore diameters that can be tuned via the template from a few nanometers to hundreds of micrometers. This architecture endows the materials with unique properties that can benefit a variety of applications, including optical, catalytic, electrochemical, and tissue engineering applications. This chapter describes synthesis–structure–property relationships of porous materials prepared by colloidal crystal templating and provides specific examples from the literature. Emphasis is placed on understanding the structural features of these materials, how to obtain these structural features from a synthetic point of view, and how the unique structures benefit specific applications. Most of the discussions are focused on 3
DOM
materials, but also apply to similar mesoporous or hierarchically structured materials prepared by colloidal crystal templating. The chapter ends with our perspectives on the field.
Predicting the Structure and Chemistry of Low‐Dimensional Materials
Authors: Yu Xiaohu , Oganov Artem R. , Wang Zhenhai , Saleh Gabriele , Sharma Vinit , Zhu Qiang , Wang Qinggao , Zhou Xiang‐Feng , Popov Ivan A. , Boldyrev Alexander I. , Baturin Vladimir S. , Lepeshkin Sergey V. 
Published: August 2017

Abstract

In this chapter, we focus on evolutionary algorithms for predicting structures of low‐dimensional systems and their applications to clusters, polymers, surfaces, and 2
D
crystals. The principles of evolutionary algorithms in application to such systems are systematically reviewed, and a number of applications are discussed, with emphasis on the structure, functionality, and chemical bonding.
Electrical Energy Storage: Batteries
Authors: McCalla Eric 
Published: August 2017

Abstract
Secondary batteries have become the dominant source of energy for personal electronics and are the most promising technology for widespread implementation of electric vehicles. Much of the innovations that have taken place in the last 20 years in the field of Li‐ion batteries (and other battery technologies) relate to the design of new materials allowing for greater energy density without compromising long‐term performance. This chapter is devoted to components of modern batteries where solid‐state chemistry has played and will continue to play a significant role. The batteries of particular interest will be Li‐ion (nearing maturity) and all solid‐state batteries (currently used for niche applications only). In metal–ion battery systems, the stoichiometry and synthesis conditions of the electrode materials have dramatic effects on the battery properties and solid‐state chemistry has therefore played a vital role in developing these technologies. Here, the topics covered will be the operation of state‐of‐the‐art batteries, the structures of typical materials used in batteries as well as their synthesis, and finally an overview of ways in which solid‐state chemistry has contributed to battery research, including a discussion of combinatorial chemistry. The prospects for all solid batteries will also be critically examined.
Dye‐Sensitized Solar Cells
Authors: Nikolskaia Anna , Shevaleevskiy Oleg 
Published: August 2017

AbstractThe dye‐sensitized nanocrystalline solar cells (DSSCs), considered as third‐ or next‐generation solar cells, attracted a significant interest as a possible cost‐attractive alternative to the conventional silicon‐based counterparts. DSSCs can achieve up to nearly 13% of certified power conversion efficiency and show great potential for large‐scale production due to using cheap materials and an economically friendly and easy fabrication process. This chapter schematically illustrates the structure and the energy level diagram of a dye‐sensitized solar cell. A variety of wide‐bandgap metal oxides, such as TiO2, ZnO, SnO2, and Nb2O5, can be used as n‐type semiconductor materials for fabricating photoanodes for DSSCs. DSSCs have a number of attractive features and advantages as compared to the conventional solid‐state silicon‐based solar cells. One of the main advantages is their high power conversion efficiency under low solar radiation and in cloudy weather conditions.
Designing Thermoelectric Materials Using 2DLayers
Authors: Bauers Sage R. , Johnson David C. 
Published: August 2017

AbstractResearch efforts over the past few decades have resulted in significant progress in the discovery of new thermoelectric materials. This includes advances in traditional bulk compounds and the introduction of new paradigms to the field, such as composite compounds, correlated electron systems, and low‐dimensional materials. Several of these results are presented, with a particular emphasis on composite structures comprised of 2D building blocks.
Functional Materials: For Sensing/Diagnostics
Authors: Munje Rujuta D. , Prasad Shalini , Graef Edward 
Published: August 2017

AbstractThere has been a tremendous growth in the field of diagnostic sensors and environmental gas sensors in the past 10 years. The global market for commercial sensors was estimated to be aroundUS$12 billion in 2015. A diagnostic sensor or a biosensor is used for recognition of molecules such as proteins, enzymes, or metabolites from body fluids. Gas sensing has become an active field of research that has far reaching implication into the future. From the viewpoint of global climate change, air quality, and toxic gas detection, gas sensors are being researched both on the industrial and on the university levels to provide tools to better understand these applications and more. The environmental gas sensors can be used for detection of gas,VOCs, or trace elements from environment. Both biosensors and environmental sensors have evolved through multiple generations based on the advancements of the functional materials that are being used for detection of the biomolecule or environmental gas of interest. Functional materials can be characterized as materials possessing special properties such as magnetic, piezoelectric, high tensile strength, capacitive energy storage, and so on. The enrichment in the field of nanotechnology in terms of growth, fabrication, and integration of nanomaterials into a sensor device has set a new paradigm for the form and function of sensor devices. This chapter reviews the current state‐of‐the‐art nanomaterial technology leveraged both for the development of protein, hormone, and enzyme biosensors and for the development of environmental gas sensors.
Catalysis/Selective Oxidation by Metal Oxides
Authors: Ueda Wataru 
Published: August 2017

AbstractSelective oxidation catalysts based on metal oxides are categorically summarized in terms of their functions derived from high dimensionality in crystalline catalytic materials, which are titanosilicate, divanadyl pyrophosphate, heteropoly compounds, molybdenum–vanadium mixed oxides, and multicomponentBi–Mooxides.
Combinatorial Approaches for Bulk Solid‐State Synthesis of Oxides
Authors: McGinn Paul J. 
Published: August 2017

AbstractCombinatorial approaches have been developed to accelerate and improve the repetitive serial synthesis and analysis of individual samples. This chapter focuses on techniques that have been utilized to process inorganic solid‐state materials, particularly in bulk or particulate form. Combinatorial powder synthesis from liquid precursors is a commonly used route in bulk high‐throughput materials studies. Liquid deposition routes are attractive to researchers because implementation is usually straightforward and relatively inexpensive. Combinatorial processing from dry powders is appealing because it scales directly to common industrial practice. A significant advantage compared to some liquid routes is that one can realize a high yield from inexpensive reagents, and it can be easily scaled to large quantities. Polymer complex methods have also been used for combinatorial powder synthesis. These methods are widely used in the synthesis of complex oxides because they are simple to utilize and synthesis occurs at lower temperature and shorter reaction times than solid‐state routes.
Construction of Pyridazine Analogues via Rhodium‐mediated C‐H Activation
Authors: Yang Chao , Song Feifei , Chen Jiean , Huang Yong 
Published: August 2017

AbstractHerein a rhodium (III)‐mediated catalysis was demonstrated for approaching the structurally divergent N,N‐bicyclic pyridazine analogues. The pyrazolidinone moiety was used to direct the ortho C−H activation and this led to a general synthesis of benzopyridazine analogues with satisfactory yields. The crucial effect of the base was illustrated in the sequential dehydration process. For mechanistic insight, control experiments were performed for illustration of the catalytic circle. Gram scale synthesis and several practical transformations were conducted for further applications.magnified image
A Biobased Flame‐Retardant Resin Based on Lignin
Authors: Matsushita Yasuyuki , Hirano Daisuke , Aoki Dan , Yagami Sachie , Takagi Yasuo , Fukushima Kazuhiko 
Published: August 2017

AbstractThis study focuses on the development of biobased flame‐retardant resins. Lignin and α,ω‐alkanediols are used, which can be obtained from biomass. To introduce intumescent properties, phosphoryl chloride and 3‐amino‐1,2,4‐triazole are introduced into kraft lignin prior to it being resinified with the α,ω‐alkanediols. In simple combustion tests using a gas burner at 1300 °C, the resins prepared exhibit nonburnable properties, producing only a swollen char. According to dynamic mechanical analysis, the glass transition temperature decreases with an increase in the carbon number and amount of the alkanediols introduced. The mechanical loss tangent (tan δ) value of the prepared resins is below 1, indicating that the resins would not drip flaming particles during burning. Indeed, the specimens do not generate particles in the simple combustion tests. According to the results of cone calorimeter testing, the total heat release and the peak heat release rate are significantly smaller than those of a commercial phenol‐formaldehyde‐resin‐containing flame retardant.
Efficient Red‐Emissive Organic Crystals with Amplified Spontaneous Emissions Based on a Single Benzene Framework
Authors: Tang Baolei , Wang Chenguang , Wang Yue , Zhang Hongyu 
Published: August 2017

AbstractRed‐emissive fluorophores generally consist of large π‐extended systems and thus encounter the problem of serious fluorescence quenching in the solid state. A series of structurally simple compounds 2,5‐bis(alkylamino)terephthalates 1 a–c are reported that consist of a very small π‐system (only a single benzene) but display efficient red emission in crystals. Crystal 1 a having a molecular weight of only 252 g mol−1 shows red emission with the maximum of 620 nm and a fluorescence quantum yield of 0.40. The unique emission property of crystal 1 a is mainly because of the planarization of skeleton dominated by the strong intramolecular hydrogen bonds and the packing structure with negligible π–π interactions contributed by the mini π‐system. Moreover, besides efficient red emission, high crystallinity with co‐planar facets endows crystal 1 a with significant amplified spontaneous emission.
Relationship between structure and physical strength of silk fibroin nanofiber sheet depending on insolubilization treatment
Authors: Fukuda Yasuhiro , Aytemiz Derya , Higuchi Akira , Ichida Yuya , Asakura Tetsuo , Kameda Tsunenori , Nakazawa Yasumoto 
Published: August 2017

ABSTRACTMaterials such as expanded polytetrafluoroethylene and glutaraldehyde‐fixed bovine pericardium are currently used for cardiac tissue regeneration. However, patches made from these materials remain permanently without being absorbed by the body and must be replaced overtime because of degeneration or lack of growth. To improve the long‐term outcomes for cardiac tissue regeneration, biocompatible and biodegradable materials must be used. In this study, we used two biocompatible polymers, silk fibroin (SF), which is biodegradable and segmented polyurethane, to prepare nonwoven sheets that were then insolubilized by water vapor or methanol treatment. The tensile stress increased significantly on adding segmented polyurethane to pure SF and the water vapor processed sheets showed higher extension on strain than the methanol‐processed sheets. The different insolubilization treatments also resulted in different SF structures. Our results show that it is possible to obtain the physical properties required for cardiac tissue repair patch by varying the insolubilization treatment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45560.
Effect of solvent quality and humidity on the porous formation and oil absorbency of SAN electrospun nanofibers
Authors: Bandegi Alireza , Moghbeli Mohammad Reza 
Published: August 2017

ABSTRACTIn this study, nanofibrous mat with high oil sorption capability was prepared via one‐step electrospinning process without any further post‐treatments. For this purpose, the fabrication of styrene/acrylonitrile copolymer nanofibers was carried out using various dimethylformamide (DMF)/tetrahydrofuran and DMF/ethanol (DMF/EtOH) binary mixture ratios in an electrospining atmosphere with various relative humidity (RH) levels. Scanning electron microscope micrographs showed that DMF/tetrahydrofuran and DMF/EtOH ratio and RH value could considerably affect the diameter, surface, and interior morphology of the resultant nanofibers. The nanofiber morphology was dependent upon the polymer/solvent(s)/water ternary phase diagram behavior. In overall, the partial hydrophilicity of styrene/acrylonitrile copolymer resulted in electrospun nanofibers with wrinkled surface. In addition, the incorporation of nonsolvent in the spinning solution and using high RH atmosphere forced the polymeric solution jet to intensively phase separate and, therefore, produce the nanofibers with highly interior porous structure during drying process. The maximal capacity and rate of oil sorption (170 g/g) was observed for the nanofibrous mat prepared using EtOH/DMF (2/3: vol/vol) and RH value of 60% showing the highest internal porosity. The results showed that the oil sorption capability and mechanical strength of the fibrous mat are strongly dependent on nanofibers diameter and porous structure, which can be controlled through adjusting the RH and spinning solvent quality. The electrospun mat with highest Young's modulus (7.68 MPa) was prepared using EtOH/DMF (2/3) binary mixture and RH value of 45%. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45586.
Diffusion and desorption of CO2 in foamed polystyrene film
Authors: Qian Ying‐Hui , Cao Jun‐Ming , Li Xue‐Kun , Cao Gui‐Ping , Wang Chang‐Chun , Shi Yun‐Hai 
Published: August 2017

ABSTRACTBased on the existence of the pores in foamed polystyrene (PS), foamed‐non‐Fickian diffusion (FNFD) model was proposed, for the first time, to regress the desorption data obtained by gravimetric method. Results showed that FNFD model could accurately describe the diffusion behavior of CO2 out of foamed PS, and well predict the solubility of CO2 in foamed PS. The characterization of scanning electron microscopy indicated that there were abundant pores in the foamed PS, and the pores store most of CO2, which would diffuse in the pores, adsorb to the wall of the pores, penetrate across walls of the pores, diffuse in the matrix of PS, and desorb out of PS. The mass of CO2 in the pores of foamed PS was expressed as a function of foaming pressure and temperature according to foaming kinetics. Results showed that the values calculated by this function agreed well with the values obtained from the FNFD model. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45645.
Random walk designs for selecting pool sizes in group testing estimation with small samples
Authors: Haber Gregory , Malinovsky Yaakov 
Published: August 2017

AbstractGroup testing estimation, which utilizes pooled rather than individual units for testing, has been an ongoing area of research for over six decades. While it is often argued that such methods can yield large savings in terms of resources and/or time, these benefits depend very much on the initial choice of pool sizes. In fact, when poor group sizes are used, the results can be much worse than those obtained using standard techniques. Tools for addressing this problem in the literature have been based on either large sample results or prior knowledge of the parameter being estimated, with little guidance when these assumptions are not met. In this paper, we introduce and study random walk designs for choosing pool sizes when only a small number of tests can be run and prior knowledge is vague. To illustrate these methods, application is made to the estimation of prevalence for two diseases among Australian chrysanthemum crops.
Single Cell Fabrication Towards the Realistic Evaluation of a CNT‐Strung ZIF‐Derived Electrocatalyst as a Cathode Material in Alkaline Fuel Cells and Metal−Air Batteries
Authors: Aiyappa Harshitha Barike , Bhange Siddheshwar N. , Sivasankaran Vijitha P. , Kurungot Sreekumar 
Published: August 2017

AbstractThe development of an electrocatalyst possessing all the vital requisites of an ideal electrode material, such as high porosity, high conductivity, and high intrinsic electrochemical activity, holds a decisive key in determining the activity of the triple‐phase boundary in many energy devices like fuel cells and metal−air battery systems. In the present work, highly porous cobalt‐based ZIFs are strung along the highly conducive CNT backbone by using a simple one‐pot technique at room temperature, which is then utilized to derive a porous, corrosion‐resistant, Co nanoparticle‐embedded electrocatalyst. Herein, for the first time, the single cell performance of the Co‐ZIF‐67‐derived electrocatalyst has been evaluated by fabricating membrane electrode assemblies of alkaline exchange membrane fuel cell (AEMFC) and zinc–air battery (ZAB) systems. A maximum power density of 296 mW/cm2 (vs. 317 mW/cm2 for 40 wt.% Pt/C) and 60 mW/cm2 (vs. 64 mW/cm2 for 40 wt.% Pt/C) in the single cells of ZAB and AEMFC systems, respectively, establishes the practical proficiency of the homemade electrocatalyst for cathode applications during realistic system‐level validations.
Aryl Transfer Selectivity in Metal‐Free Reactions of Unsymmetrical Diaryliodonium Salts
Authors: Stuart David R. 
Published: August 2017

AbstractAromatic rings are found in a wide variety of products, including pharmaceuticals, agrochemicals, and functional materials. Diaryliodonium salts are new reagents used to transfer aryl groups under both metal‐free and metal‐catalyzed reactions and thereby synthesize arene‐containing compounds. This minireview focuses on recent studies in selective aryl transfer reactions from unsymmetrical diaryliodonium salts under metal‐free conditions. Reactions reported from 2007 to 2017, which represents a period of significant growth in diaryliodonium salt chemistry, are presented and organized by the type of reactive intermediate formed in the reaction. Specifically, reactions involving λ3‐iodane, λ3‐iodane radical anions, aryl radicals, and arynes are discussed. Chemoselectivity trends in aryl transfer are compared and contrasted across reaction intermediates and translation to potential auxiliaries are posited.
Competing Pathways in O‐Arylations with Diaryliodonium Salts: Mechanistic Insights
Authors: Stridfeldt Elin , Lindstedt Erik , Reitti Marcus , Blid Jan , Norrby Per‐Ola , Olofsson Berit 
Published: August 2017

AbstractA mechanistic study of arylations of aliphatic alcohols and hydroxide with diaryliodonium salts, to give alkyl aryl ethers and diaryl ethers, has been performed using experimental techniques and DFT calculations. Aryne intermediates have been trapped, and additives to avoid by‐product formation originating from arynes have been found. An alcohol oxidation pathway was observed in parallel to arylation; this is suggested to proceed by an intramolecular mechanism. Product formation pathways via ligand coupling and arynes have been compared, and 4‐coordinated transition states were found to be favored in reactions with alcohols. Furthermore, a novel, direct nucleophilic substitution pathway has been identified in reactions with electron‐deficient diaryliodonium salts.
Reducing the Flexibility of Type II Dehydroquinase for Inhibition: A Fragment‐Based Approach and Molecular Dynamics Study
Authors: Peón Antonio , Robles Adrián , Blanco Beatriz , Convertino Marino , Thompson Paul , Hawkins Alastair R. , Caflisch Amedeo , González‐Bello Concepción 
Published: August 2017

AbstractA multidisciplinary approach was used to identify and optimize a quinazolinedione‐based ligand that would decrease the flexibility of the substrate‐covering loop (catalytic loop) of the type II dehydroquinase from Helicobacter pylori. This enzyme, which is essential for the survival of this bacterium, is involved in the biosynthesis of aromatic amino acids. A computer‐aided fragment‐based protocol (ALTA) was first used to identify the aromatic fragments able to block the interface pocket that separates two neighboring enzyme subunits and is located at the active site entrance. Chemical modification of its non‐aromatic moiety through an olefin cross‐metathesis and Seebach's self‐reproduction of chirality synthetic principle allowed the development of a quinazolinedione derivative that disables the catalytic loop plasticity, which is essential for the enzyme′s catalytic cycle. Molecular dynamics simulations revealed that the ligand would force the catalytic loop into an inappropriate arrangement for catalysis by strong interactions with the catalytic tyrosine and by expelling the essential arginine out of the active site.