bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field Flow Fractionation
Authors: Lespes Gaëtane , Gigault Julien , Battu Serge 
Published: November 2015

Abstract

This chapter discusses the principle and theory, instrumentation, and main applications of field flow fractionation (FFF). As material sciences, environmental management, and biology/ medicine generate large expectations about characterization of nano‐ and microsized analytes, particular attention is given to these areas of applications. FFF is based on the migration of analytes in a liquid (mobile phase) flowing through a channel. Fractionation occurs in the channel for which there are different versions according to the different natures of fields applied. FFF is of great interest for analytical strategies based on separation and characterization of nano‐ and microsized analytes. Therefore, FFF is involved in a wide range of applications concerning analytes of extremely varied origins (natural, nonintentionally produced, or manufactured) and nature (organic, inorganic, or both; particles, macromolecules, living organisms, and emulsions).
Separations with a Liquid Stationary Phase: Countercurrent Chromatography or Centrifugal Partition Chromatography
Authors: Berthod Alain , Faure Karine 
Published: November 2015

Abstract

Ever since Yoichiro Ito reported the separation of blood plasma cells with a sealed helical tube in 1966, countercurrent chromatography (
CCC
) has been a fertile ground for instrumental and technical innovations. The key innovation of
CCC
was to use centrifugal forces to retain the stationary liquid phase in the column in such a way that it can interact dynamically with mobile phase without any solid support. The great diversity of countercurrent separation terminology reflects both the innovative spirit of the field and the global appeal of this technique. The selected biphasic liquid system is the core of the
CCC
technique. The
CCC
columns must be able to generate the centrifugal field needed to maintain the liquid stationary phase. They cannot be a simple tube with frits at both ends. Rotors, gears, spools, and rotating seals are very specific things that are not needed in classical
LC
with a solid stationary phase. This chapter describes the commercially available
CCC
columns and few practical examples. The special terminology used in
CCC
is explained sorting terms into three classes: the terms linked to the
CCC
instrumentation, the terms linked to
CCC
operation, and the terms coming from the biphasic liquid system.
Fast and Miniaturized Chromatography
Authors: Socas‐Rodríguez Bárbara , Herrera‐Herrera Antonio V. , González‐Curbelo Miguel Ángel , González‐Sálamo Javier , Hernández‐Borges Javier 
Published: November 2015

AbstractThis chapter provides a general overview of the different aspects, characteristics, and applications that involve the use of fast liquid chromatography (LC) and gas chromatography (GC) as well as the miniaturized versions of both techniques such as capillary/nano‐LC, micro‐GC, capillary electrochromatography (CEC), and chips. Moreover, the primary objective of the early use of GC techniques was to completely resolve multi‐component mixtures in complex matrices and the attention on analysis time was delayed. The chapter presents the current trends in fast LC separations, which involve monolith technologies, fused core columns, sub‐2 μm particles, high‐temperature liquid chromatography (HTLC), and ultrahigh‐performance liquid chromatography (UHPLC), as well as fast GC separations that can be basically achieved by the use of narrow‐bore columns, fast temperature programming, or low‐pressure gas chromatography (LPGC).
Main uses of Microwaves and Ultrasounds in Analytical Extraction Schemes: an Overview
Authors: Pacheco‐Fernández Idaira , González‐Hernández Providencia , Rocío‐Bautista Priscilla , Trujillo‐Rodríguez María José , Pino Verónica 
Published: November 2015

AbstractThe utilization of microwaves and/or ultrasounds in analytical extraction procedures is a common practice nowadays. Both extraction approaches can be classified as routine/conventional tools. This chapter intends to give an overview of main applications of microwaves and/or ultrasounds as neat analytical approaches, assisting other extraction methods, or combined with other procedures in a hybrid strategy. Advances in the instrumentation together with the utilization of novel solvents will be also highlighted. The chapter will also show most common applications as a function of the nature of the analyte or the kind of sample analyzed.
Membrane‐assisted Separations
Authors: Jönsson Jan Åke 
Published: November 2015

AbstractVarious membrane‐based extraction techniques are used for sample pretreatment in analytical chemistry prior to using chromatographic or other techniques for the final determination. Such techniques show several advantages over other extraction. They lead to large selectively for several types of analytes in even complex samples and high‐concentration enrichment, easily thousands of times. The most common format for membrane extraction involves hollow‐fiber membranes. This permits easy, convenient, and cost‐effective operation. Many applications involve the liquid chromatographic determination of polar and medium‐polar compounds as acids and bases in samples of environmental and biological origin. Also, the determination of nonpolar compounds in, for example, environmental samples, followed by gas chromatography is described.This chapter describes the basic theoretical and practical principles for the common types of membrane extraction, together with some applications.
Solid‐Phase Extraction
Authors: Ozbek Nil , Baysal Asli , Akman Suleyman , Dogan Mehmet 
Published: November 2015

Abstract

Solid‐phase extraction (SPE) is a sample preparation process that uses solid particle as sorbents, to chemically or physically separate the different components of a liquid or gas sample. It can be either used for
extraction
, that is, removal of sample matrix/concentrating compounds with a small volume of eluent or for
cleanup
that is, to remove unwanted molecules from the sample. When using SPE, the user should be aware of different strategies (extraction, fractionation, and cleanup), different interactions between components and sorbents (normal phase, reversed phase, ion‐exchange, and molecular recognition), different formats (syringe barrel, disk type, packed bed, pipette tip, well‐plate, and spin column), and different sampling types (online and offline
SPE
) for different applications.The objective of this chapter is to provide a simple explanation for
SPE
techniques and give some examples for new SPE materials. In the chapter, first,
SPE
's development history has been explained. Furthermore, theoretical background and
SPE
strategies have been described with detailed figures. Second, types of
SPE
interactions and sample requirements are clarified using tables. In addition to that
SPE
formats and online SPE applications are mentioned. Finally, different sorbents used in
SPE
applications in the last decade have been explained by giving their advantages and disadvantages.
“Omics” and Biomedical Applications
Authors: Ferranti Pasquale , Nitride Chiara , Gallo Monica 
Published: November 2015

AbstractExtensive research has shown that data generated by the various omic technologies represent a unique resource for biologists. This chapter explores how classical approaches to study biological processes, such as those used in chemistry, biochemistry, immunology, and genetics, intersect with the new omics technologies to advance the understanding of biological systems by examination of case studies of general interest for researchers. It explores the development of simple and robust methods for understanding the meaning of omics data in biomedical sciences. The chapter highlights that instead of looking at one potential biomarker at a time, the new techniques in genomics, transcriptomics, proteomics, metabolomics, lipidomics, and glycomics have allowed researchers to identify patterns in the changes of many genes and compounds that correlate with disease state. Mass spectrometry (MS) and spectroscopic techniques are the key analytical platforms on which the emerging omics technologies are based.
Food Applications: Using Novel Sample Preparation Modes
Authors: González Mónica , González Venerando 
Published: November 2015

Abstract

For safety, sensory, nutritional, and commercial reasons, the entire process from food production and packaging to introduction into the market must be carefully monitored. Sample preparation is the most critical step in the analysis of foods, because the isolated analytes must reflect the condition in which they are found in the natural food matrix, with no changes in their chemical configuration. Conventional techniques used to prepare food samples prior to analysis have several drawbacks: they are often laborious and time‐consuming, have low extraction yield and/or low selectivity, and require large amounts of solvents and reagents. Therefore, more effective, selective, environmentally friendly and safer techniques are being developed to extract analytes from food samples. In this chapter some of the most innovative techniques used to analyze foods are outlined, briefly discussing some of their advantages and drawbacks.
Forensic Applications
Authors: Guerreiro Matías Calcerrada , López‐López María , Fernández de la Ossa Ma Ángeles , García‐Ruiz Carmen 
Published: November 2015

AbstractThe forensic process encompasses many stages from the initial investigation of a crime scene to the presentation of witness testimony in court. Most of the current analytical techniques used to analyze forensic evidence require a sample preparation prior to the analytical stage. This chapter provides an overview of the novel sample preparation modes, published up to date, for samples of forensic interest. This information has been grouped into the three following themes: explosives and related samples, drugs and toxicological analysis, and other forensic samples. The identification of explosives and related samples has become a heightened priority in recent years for homeland security and counterterrorism applications. The chapter also discusses drug analyses and forensic toxicology. A transition to noninvasive and nondestructive analysis avoiding any sample treatment is expected in the near future for most forensic evidence.
Strukturell definierte molekulare hypervalente Iod‐Katalysatoren für intermolekulare enantioselektive Reaktionen
Authors: Haubenreisser Stefan , Wöste Thorsten H. , Martínez Claudio , Ishihara Kazuaki , Muñiz Kilian 
Published: November 2015

AbstractDie Molekülstrukturen der gegenwärtig besten chiralen, nichtracemischen hypervalenten Iod(III)‐Reagentien wurden zum ersten Mal aufgeklärt. Die induzierte Bildung einer chiralen supramolekularen Struktur basierend auf Wasserstoffbrücken liefert eine Erklärung für die konsequent hohen asymmetrischen Induktionen mit diesen Reagentien. Ihr Anwendungsbereich wurde auf die enantioselektive Dioxygenierung von Alkenen erweitert. Eine Reihe von terminalen Styrolen wurde entsprechend unter milden Bedingungen in die Produkte der vicinalen Diacetoxylierung überführt. Bei dieser Umwandlung handelt es sich um die erste intermolekulare asymmetrische Oxidation von Alkenen unter Iod(I/III)‐Katalyse.
Palladium(II)‐Catalyzed Synthesis of Sulfinates from Boronic Acids and DABSO: A Redox‐Neutral, Phosphine‐Free Transformation
Authors: Deeming Alex S. , Russell Claire J. , Willis Michael C. 
Published: November 2015

AbstractA redox‐neutral palladium(II)‐catalyzed conversion of aryl, heteroaryl, and alkenyl boronic acids into sulfinate intermediates, and onwards to sulfones and sulfonamides, has been realized. A simple Pd(OAc)2 catalyst, in combination with the sulfur dioxide surrogate 1,4‐diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO), is sufficient to achieve rapid and high‐yielding conversion of the boronic acids into the corresponding sulfinates. Addition of C‐ or N‐based electrophiles then allows conversion into sulfones and sulfonamides, respectively, in a one‐pot, two‐step process.
Air Passivation of Chalcogen Vacancies in Two‐Dimensional Semiconductors
Authors: Liu Yuanyue , Stradins Pauls , Wei Su‐Huai 
Published: November 2015

AbstractDefects play important roles in semiconductors (SCs). Unlike those in bulk SCs, defects in two‐dimensional (2D) SCs are exposed to the surrounding environment, which can potentially modify their properties/functions. Air is a common environment, yet its impact on the defects in 2D SCs still remains elusive. Here we study the interaction between air and chalcogen vacancies (VX), the most typical defects in 2D SCs. Although the interaction is weak for most molecules in air, O2 can be chemisorbed at VX with a barrier that correlates with the SC cohesive energy and can be overcome even at room temperature for certain SCs. Importantly, the chemisorbed O2 changes the VX from commonly believed harmful carrier‐traps to electronically benign sites. This unusual behavior originates from the isovalence between O2 and X when bonded with metal. Based on these findings, a facile approach is proposed to improve the performance of 2D SCs by using air/O2 to passivate the defects.
Dative Bonding between Group 13 Elements Using a Boron‐Centered Lewis Base
Authors: Braunschweig Holger , Dewhurst Rian D. , Pentecost Leanne , Radacki Krzysztof , Vargas Alfredo , Ye Qing 
Published: November 2015

AbstractAn electron‐rich monovalent boron compound is used as a Lewis base to prepare adducts with Group 13 Lewis acids using both its boron and nitrogen sites. The hard Lewis acid AlCl3 binds through a nitrogen atom of the Lewis base, while softer Lewis acids GaX3 (Cl, Br, I) bind at the boron atom. The latter are the first noncluster Lewis adducts between a boron‐centered Lewis base and a main‐group Lewis acid.
Aggregation effects on water base Al2O3—nanofluid over permeable wedge in mixed convection
Authors: Ellahi R. , Hassan M. , Zeeshan A. 
Published: November 2015

AbstractTwo‐dimensional heat transfer flow of a nanofluid in the neighborhood of a stagnation point flow in the presence of mixed convection is investigated. The mathematical model consists of continuity and the momentum equations, while a new model is proposed to see the effects aggregations on water base Al2O3 nanofluid over permeable wedge. The variable wall temperature is taken into account. The Mathematica package based on homotopy analysis method is used to solve this problem. Several aspects of the aggregation parameters on velocity and temperature profiles of nanofluid are investigated and shown graphically with respect to the physical parameters involved in it. The tabular results are demonstrated for heat transfer rate and skin friction coefficient. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd.
Interaction and properties of epoxy‐amine system modified with poly(phthalazinone ether nitrile ketone)
Authors: Liu Rui , Wang Jinyan , He Qinzheng , Zong Lishuai , Jian Xigao 
Published: November 2015

ABSTRACTAn epoxy based on the tetraglycidyl 4,4′‐diaminodiphenyl‐ methane (TGDDM)/bisphenol A type novolac(F‐51) cured with 4,4′‐diaminidiphenysulfone (DDS) has been modified with Poly (phthalazinone ether nitrile ketone)(PPENK). The interaction between the PPENK and epoxy resin have been investigated by differential scanning calorimetry (DSC), FT‐IR, and dynamic mechanical analysis (DMA). The thermal and mechanical properties were characterized by thermogravimetric analysis (TGA), thermomechanical analysis (TMA), flexural, impact strength, and the critical stress intensity factor tests. The results showed that a large number of physical crosslinks formed by intermolecular and intramolecular hydrogen bonding indeed existed in the TGDDM/F‐51/PPENK blends. These interactions gave good compatibility between PPENK and epoxy resin. So that any phase separation had not been detected by DMA and scanning electron microscope (SEM). Beyond that the interaction could also be a benefit to the thermal and mechanical properties. Compared with the neat epoxy resin, the critical stress intensity factor values reached the maximum at 10‐phr PPENK, as well as the impact strength. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42938.
Synthesis of aminated glycidyl methacrylate grafted rice husk and investigation of its anion‐adsorption properties
Authors: Temesgen Tatek , Park Hyunju , Na Choonki 
Published: November 2015

ABSTRACTIn this study, we focused on the synthesis, characterization, and adsorption capacity testing of aminated glycidyl methacrylate grafted rice husk (RH‐g‐GMA–Am). Our goal was to obtain a high‐performance surface for the adsorption of various anions. Glycidyl methacrylate grafted rice husk (RH‐g‐GMA) was prepared by the graft copolymerization of glycidyl methacrylate with rice husk; the product was further subjected to an amination reaction. The surface properties, sorption characteristic functional groups, isotherm and kinetic studies, pore diffusion models, and effects of the temperature and pH on the material properties were studied under batch conditions. The IR spectroscopy results show additional surface functional groups for RH‐g‐GMA–Am. The adsorptions of
and
on RH‐g‐GMA–Am were found to follow pseudo‐second‐order kinetics; this indicated a possible dominant role played by chemisorption. The rate‐limiting step for mass transfer was found to be boundary layer diffusion. Furthermore, the sorption isotherms for
and
fit the Langmuir model. The amination of RH‐g‐GMA drastically increased the removal efficiency from 3 to 82% and from 6 to 93% for
and
, respectively. Moreover, RH‐g‐GMA–Am exhibited a better
removal efficiency in the pH range of 4–6.5. Regeneration studies revealed that the surface of RH‐g‐GMA–Am could be regenerated repetitively by simple acid washing with an insignificant decrease in the active surface for consecutive adsorptions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43002.
Multilayer photoactive nanocolloidal PPy:PSS as a novel substitute for Pt free counter electrode in DSSC
Authors: Maruthamuthu S. , Chandrasekaran J. , Manoharan D. , Karthick S. N. , Kim Hee‐Je 
Published: November 2015

ABSTRACTWater dispersible and highly processable, Polypyrrole (PPy) nanocolloidal particles were synthesized by chemical oxidation polymerization with 15 wt % of anionic polyelectrolyte poly(styrene sulfonate) (PSS) at 5°C has been reported in this work. This polymer composite (PPy:PSS) was competent with conventional Pt counter electrode (CE) when compared for dye sensitized solar cells (DSSCs). Morphological analysis revealed smooth and spherical shaped nanoparticles of PPy. Interaction between the SO3H groups and Py units in PPy improved the thermal stability of PPy with higher doping levels of PSS. The nanocolloidal solution was spin coated at 4000 rpm. The layer by layer, self‐assembled multilayer thin films were used as CE in DSSCs. There was a linear dependence of DSSCs performance with film roughness for the self‐assembled multilayer PPy:PSS films. Single layer films showed better electrocatalytic behavior than multilayer films. All the PPy:PSS films had good electrochemical stability. The DSSC efficiency of 3.40% was observed for chemically oxidized PPy with 15 wt % PSS for single layer film, with a highest FF of 0.7154. The low cost, good performance, rapid and simple fabrication method of PPy:PSS composite modified CE could be a potential alternative for Pt in the DSSCs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43114.
A novel mono‐methacryloyloxy terminated fluorinated macromonomer used for the modification of UV curable acrylic copolymers
Authors: Tan Jianquan , Liu Weiqu , Wang Honglei , Sun Yang , Wang Shijian 
Published: November 2015

ABSTRACTA novel macromonomer containing fluorinated units (PHFBMA‐GMA) was synthesized through a two‐step procedure: firstly, hexafluoro‐butyl methacrylate (HFBMA) was polymerized in the presence of functional chain transfer agent 3‐mercaptopropionic acid (MPA) and then the carboxyl acid group terminated polymer was end‐capped with glycidyl methacrylate (GMA). Chemical structures of PHFBMA‐GMA were characterized by gel permeation chromatography, fourier transform infrared spectroscopy (FTIR), and 1H nuclear magnetic resonance (NMR). Subsequently, PHFBMA‐GMA was employed as reactive surface additives added into UV‐cured polyacrylate to modify UV‐curable coatings. It is convenient to control the tail length of the fluorinated segments in this study by adjusting the ratio of initiator and chain transfer agent. The influence of both the concentration and the molecular weight of PHFBMA‐GMA on the surface properties of UV‐cured films was investigated. With increasing both the concentration and the molecular weight of PHFBMA‐GMA, the surface energy of the UV‐cured films decreased. X‐ray photoelectron spectroscopy was employed to characterize and quantify the surface composition and the results confirm the enrichment of fluorinate atoms on the surface. Moreover, the physical properties of UV‐cured films, such as gel content, water absorption, pencil hardness, adhesion, chemical resistance, mechanical properties, optical transmittance, and thermal properties, were also investigated in detail. The novel macromonomer was economical but effective to modify the properties of the UV‐curable coatings. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43116.
Adaptive Controller Design for Unknown Systems Using Measured Data
Authors: Khadraoui Sofiane , Nounou Hazem N. , Nounou Mohamed N. , Datta Aniruddha , Bhattacharyya Shankar P. 
Published: November 2015

AbstractThis paper presents a measurement‐based adaptive control design approach for unknown systems working over a wide range of operating conditions. Traditional control design approaches usually require the availability of a mathematical model. However, it has been shown in many practical situations that, due to complex dynamics of physical systems, some simplifying assumptions are made for the derivation of mathematical models. Hence, controller design based on simplified models may result in degradation of the desired closed‐loop performance. Data‐based control design approaches can be viewed as an alternative approach to model‐based methods. Most data‐based control methods available in the literature aim to design controllers for unknown systems that operate only at a given operating point. However, the dynamical behavior of plants may change for different operating conditions, which makes the task of designing a controller that works over the entire range of operating conditions more challenging. In this paper, we address such a problem and propose to design adaptive controllers based on measured data. Such a proposed method is based on designing a set of measurement‐based controllers validated at a finite set of pre‐specified operating points. Then, the parameters of the adaptive controller are obtained by interpolating between the set of pre‐designed controller parameters to derive a gain‐scheduling controller. Moreover, low‐order adaptive controllers can be designed by simply selecting the desired controller structure. The efficacy of the proposed approach is experimentally validated through a practical application to control a heating system operated over a large range of flow rate.