bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and Application of Isocyanide‐based Multicomponent Reactions
Authors: Zhu Jieping , Wang Qian , Wang Mei‐Xiang 
Published: April 2012

AbstractMulticomponent reaction (MCR) is a process in which three or more reactants are combined in a single chemical operation to produce a compound that incorporates substantial portions of all starting materials. They are by definition sustainable chemistry and are inherentlychemo‐ and regioselective, a prerequisite for a successful MCR since at least three reactive functional groups are involved and they react in an ordered and selective fashion;atom‐economic since most of them involve addition rather than substitution reactions;step‐efficient since they create at least two chemical bonds in one operation;convergent and efficient in generating molecular complexity and diversity;cost‐effective since they reduce waste production significantly by minimizing the number of costly end‐of‐pipe treatments by decreasing the number of synthetic steps;operationally simple since most of the MCRs are performed under mild reaction conditions and in some cases even proceed spontaneously in the absence of an external reagent.Using isocyanide‐based MCRs as examples, the recent development and applications of this family of MCRs are illustrated in the context of green chemistry. Most of MCRs discussed in this chapter satisfy the following criteria:need no external reagent or, if required, in only a catalytic amount;produce minimum amounts of side products, in most cases water and low molecular weight alcohols;require no protective groups;create more than two chemical bonds.
Flow Syntheses
Authors: Wiles Charlotte , Watts Paul 
Published: April 2012

AbstractWith the chemical industry acknowledging its pivotal role in the development and application of sustainable processes, the emergence of micro reaction technology, and more broadly flow chemistry, has captured the attention of chemists in all disciplines, ranging from those involved in research and development to those concerned with large‐scale production. From a financial perspective, there are several drivers for the chemical industry to adopt greener and more sustainable practices; these include the increasing costs associated with petrochemicals and hazardous waste disposal, along with problems associated with the supply of chemicals; recently highlighted by the worldwide shortage of acetonitrile. An example of the form that such an improvement might take includes increasing atom efficiency; this could be achieved through the use of catalysts, reducing the number of reaction steps, or moving towards multicomponent reactions, all of which reduce the volume of hazardous waste generated and raw materials consumed.
Synthesis Assisted by Electricity
Authors: Yoshida Jun‐ichi , Suga Seiji 
Published: April 2012

AbstractThe sections in this article areElectroorganic Synthesis in Green Reaction Media (Homogeneous System)Electroorganic Synthesis in Aqueous SolutionsElectroorganic Synthesis in Supercritical Carbon DioxideElectroorganic Synthesis in Ionic LiquidsElectroorganic Synthesis in Liquid–Liquid Biphasic SystemsElectroorganic Synthesis in Thermomorphic Liquid–Liquid Biphasic SystemsElectroorganic Synthesis in Solid–Liquid Biphasic SystemsSolid‐Supported MediatorsSolid–Liquid Biphasic System for Electrolysis Without Intentionally Added Supporting ElectrolyteSPETechnologyElectrolysis Using Solid‐Supported BasesElectroorganic Synthesis in Microflow SystemsElectrochemical Microflow CellsPaired Electrolysis in Microflow SystemsElectroorganic Synthesis in a Microflow System Without Using Intentionally Added Supporting ElectrolyteFuture Outlook
Parameterization and Tracking of Optimization of Synthesis Strategy Using Computer Spreadsheet Algorithms
Authors: Andraos John 
Published: April 2012

Abstract

This chapter presents a methodology for parameterizing synthesis strategy using green metrics for the purpose of understanding synthesis design. With respect to material efficiency, synthesis plans are evaluated with respect to atom economy (
AE
), kernel reaction mass efficiency (
RME
), molecular weight building up parameter, degree of convergence, and degree of asymmetry using the synthesis tree algorithm. These parameters are easily calculated using simple template computer spreadsheet programs which are applicable to linear and convergent plans. With respect to synthesis efficiency, new concepts are introduced, namely hypsicity (oxidation level) index, target structure mapping, molecular weight fraction of sacrificial reagents used, and target bond‐forming reaction profiles. All of these ideas are illustrated using lysergic acid as a model synthesis target.
A Review of Green Synthesis of Nanophase Inorganic Materials for Green Chemistry Applications
Authors: Genuino Homer , Huang Hui , Njagi Eric , Stafford Lisa , Suib Steven L. 
Published: April 2012

Abstract
The sections in this article are

Introduction

Green Synthesis of Nanophase Inorganic Materials

Metal Oxide Nanoparticles

Hydrothermal Synthesis

Reflux Synthesis

Microwave‐Assisted Synthesis

Green Synthesis of Metallic Nanoparticles

Green Chemistry Applications of Inorganic Nanomaterials

Manganese Oxides

Titanium Dioxide

Environmental Applications of Nanomaterials

Background

Titanium Dioxide Nanomaterials

Zinc Oxide Nanomaterials

Iron‐Based Nanomaterials

Conclusion and Future Perspectives

Acknowledgment
Drugs
Authors: Kümmerer Klaus 
Published: April 2012

AbstractThe sections in this article areIntroductionPharmaceuticals – What They ArePharmaceuticals in the Environment – Sources, Fate, and EffectsSourcesFateEffectsRisk Management(Advanced) Effluent Treatment and Its LimitationsRole of Patients, Pharmacists, and DoctorsRole of the DrugsDesigning Environmentally Safe DrugsWhat are Safe Drugs?Improvements Related to Use and After‐Use LifeLower Activity ThresholdsProdrugsDrug Targeting, Drug Delivery, Degree of MetabolismBiopharmaceuticalsBenign by DesignWhy?How?Degradable Drugs – a Contradictionper se?Structure MattersStability Versus Reactivity – How Stable Is Reactive EnoughExamples Demonstrating FeasibilityConclusion
Greener Chelating Agents
Authors: Dixon Nicholas J. 
Published: April 2012

AbstractMost water contains metal ions which can cause detrimental effects to chemical processes in the home and in industry. Metal ions in the environment are often controlled or removed by the use of chelating agents so as to prevent these effects. However, commonly used chelating agents are poorly biodegradable and concerns have been raised about their environmental effects. Considerable effort has gone into designing greener, more biodegradable alternatives, but as the reactivity of the alternatives is not the same as that of the original chelating agents, chemists have had to use their skill to find new, greener designs that are as effective without harming the environment.
Biochemical Pesticides: Green Chemistry Designs by Nature
Authors: Jones Russell S. 
Published: April 2012

AbstractThe sections in this article areIntroductionThe Historical Path to Safer PesticidesReduced‐Risk Conventional PesticidesThe Biopesticide Alternative: an OverviewBiochemical PesticidesNatural OccurrenceNontoxic Mode of Action Against the Target PestPlant RegulatorsSemiochemicalsBiological BarriersInduced Plant ResistanceHistory of Nontoxic Exposure to Humans and the EnvironmentAre Biochemical Pesticides the Wave of the Future?ConclusionDisclaimer
Cure kinetic study of epoxidized hemp oil cured with a multiple catalytic system
Authors: Manthey Nathan W. , Cardona Francisco , Aravinthan Thiru 
Published: April 2012

AbstractThe cure kinetics of two epoxidized hemp oil (EHO) based bioresins were studied and compared under both dynamic and isothermal conditions using differential scanning calorimetry (DSC). Neat triethylenetetramine (TETA) for the first system and a combination of isophorone diamine (IPD) and TETA for the second system were used as the hardeners for the two EHO‐based bioresins. Lower total heats of reaction and an approximate 10% decrease in activation energies were observed for the IPD/TETA system. Maximum conversions of the TETA/IPD system were consistently higher than those of the TETA system throughout the entire temperature range suggesting enhanced curing characteristics. Kissinger and Ozawa–Flynn–Wall models were used to determine activation energies from dynamic DSC data. Both bioresin systems were found to display autocatalytic behavior with the TETA/IPD system showing high nth order influence. Kamal's autocatalytic isothermal model, modified to account for diffusion postvitrification was found to satisfactorily describe the cure behavior of both bioresin systems. Overall, the addition of IPD was found to increase the curing rate of the EHO bioresin systems. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation and photoluminescent characterization of poly(phenylene vinylene)/TiO2 nanoparticles composite nanofibers by one‐step electrospinning
Authors: Xie Yang , Sun Liguo , Wang Cheng , Wang Shuhong , Xu Guoqiang , Zhang Jian , Yan Eryun 
Published: April 2012

AbstractA simple electrospinning progress, directly mixing method, was used to produce ultrafine poly(phenylene vinylene)/TiO2 (PPV/TiO2) composite nanofibers with diameters ranging from 100 to 300 nm. The effects of different TiO2 content on diameter, morphology, and structure of composite fibers were analyzed by scanning electron microscopy and transmission electron microscope. The results showed that composite polymer nanofibers with smooth surface were obtained when TiO2 concentration was below 18 wt %. The surface of the composite nanofibers became rougher with the increase of TiO2 content. The optical properties of the as‐prepared nanofibers were characterized by photoluminescence spectra and photographs, the results showed an increase in intensity of the high‐energy shoulder (510 nm) when the concentration of nanoparticles increased. X‐ray diffraction measurements showed that the increasing TiO2 content enhanced the amorphous phase of PPV in composite nanofibers. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Rubber content effect on scratch behavior in acrylonitrile‐styrene‐acrylate copolymers
Authors: Liang Yi‐Ling , Sue Hung‐Jue , Minkwitz Rolf 
Published: April 2012

AbstractThe scratch behavior of butyl‐acrylate rubber‐modified styrene‐acrylonitrile thermoplastics is investigated following the ASTM D7027 linearly increasing normal load test methodology. The critical normal loads at the onset of the major transitions along the scratch path, such as groove formation, scratch visibility, microcrack formation, and plowing, are reported and quantitatively analyzed. It is found that the scratch resistance generally deteriorates with increasing butyl‐acrylate rubber content, and is strongly related to the tensile and compressive yield stresses of the blends. Microscopy investigation indicates that a rubber content of up to 30 wt % in a styrene‐acrylonitrile copolymer (SAN) does not alter the scratch‐induced damage mechanisms, but only reduces the critical onset loads for the observed damage transitions. The present finding suggests that addition of rubber causes reductions in modulus, tensile, and compressive yield stresses, thus leading to deterioration in scratch resistance. It appears that the improvement in ductility for SAN after the rubber toughening does not benefit scratch resistance. Implication of rubber toughening on scratch behavior of polymers is discussed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Rapid and simple determination of psychotropic phenylalkylamine derivatives in urine by direct injection liquid chromatography–electrospray ionization–tandem mass spectrometry
Authors: Kwon Woonyong , Kim Jin Young , Suh SungIll , In Moon Kyo 
Published: April 2012

ABSTRACTA direct injection liquid chromatography–electrospray ionization–tandem mass spectrometric method (LC‐ESI‐MS/MS) was developed and validated for the rapid and simple determination of 13 phenylalkylamine derivatives. Eight deuterium‐labeled compounds were prepared for use as internal standards (ISs) to quantify the analytes. Urine samples mixed with ISs were centrifuged, filtered through 0.22 µm filters and then injected directly into the LC‐ESI‐MS/MS system. The mobile phase was composed of 0.2% formic acid and 2 mM ammonium formate in distilled water and 0.2% formic acid and 2 mM ammonium formate in acetonitrile. The analytical column was a Capcell Pak MG‐II C18 (150 × 2.0 mm i.d., 5 µm, Shiseido). Separation and detection of the analytes were accomplished within 10 min. The linear ranges were 5–750 ng/mL (ephedrine and fenfluramine), 10–750 ng/mL (3,4‐methylenedioxyamphetamine, phendimetrazine, methamphetamine, 3,4‐methylenedioxyethylamphetamine and benzphetamine), 20–750 ng/mL (norephedrine, amphetamine, phentermine and ketamine) and 30–1000 ng/mL (3,4‐methylenedioxymethamphetamine and norketamine), with determination coefficients, R2, ≥ 0.9967. The intra‐day and inter‐day precisions were within 19.1%. The intra‐day and inter‐day accuracies ranged from −16.0 to 18.7%. The lower limits of quantification for all the analytes were lower than 26.5 ng/mL. The applicability of the method was examined by analyzing urine samples from drug abusers (n = 30). Copyright © 2012 John Wiley & Sons, Ltd.
Complexes of IrIII‐Octaethylporphyrin with Peptides as Probes for Sensing Cellular O2
Authors: Koren Klaus , Dmitriev Ruslan I. , Borisov Sergey M. , Papkovsky Dmitri B. , Klimant Ingo 
Published: April 2012

AbstractIrIII–porphyrins are a relatively new group of phosphorescent dyes that have potential for oxygen sensing and labeling of biomolecules. The requirement of two axial ligands for the IrIII ion permits simple linkage of biomolecules by a one‐step ligand‐exchange reaction, for example, using precursor carbonyl chloride complexes and peptides containing histidine residue(s). Using this approach, we produced three complexes of IrIII–octaethylporphyrin with cell‐penetrating (Ir1 and Ir2) and tumor‐targeting (Ir3) peptides and studied their photophysical properties. All of the complexes were stable and possessed bright, long‐decay (unquenched lifetimes exceeding 45 μs) phosphorescence at around 650 nm, with moderate sensitivity to oxygen. The Ir1 and Ir2 complexes showed positive staining of a number of mammalian cell types, thus demonstrating localization similar to endoplasmic reticulum and ATP‐ and temperature‐independent intracellular accumulation (direct translocation mechanism). Their low photo‐ and cytotoxicity allows intracellular oxygen to be probed.
Palladium‐Catalyzed Asymmetric Quaternary Stereocenter Formation
Authors: Gottumukkala Aditya L. , Matcha Kiran , Lutz Martin , de Vries Johannes G. , Minnaard Adriaan J. 
Published: April 2012

AbstractAn efficient palladium catalyst is presented for the formation of benzylic quaternary stereocenters by conjugate addition of arylboronic acids to a variety of β,β‐disubstituted carbocyclic, heterocyclic, and acyclic enones. The catalyst is readily prepared from PdCl2, PhBOX, and AgSbF6, and provides products in up to 99 % enantiomeric excess, with good yields. Based on this strategy, (−)‐α‐cuparenone has been prepared in only two steps.
Glutamic Acid Modified Fenton System for Degradation of BTEX Contamination
Authors: Yehia Fatma Z. , Kandile Nadia G. , Badawi Abdelfatah M. , Mady Amr H. 
Published: April 2012

AbstractThe present study employed a modified Fenton system that aims to extend the optimum pH range towards neutral conditions for studying the oxidation of benzene, toluene, ethyl benzene, xylenes (BTEX) using glutamic acid (Glu) as an iron chelator. Addition of 20 mM Glu greatly enhanced the oxidation rate of BTEX in modified Fenton system at pH 5–7. A rapid mass destruction (>97% after 1 h) of BTEX as a water contaminant carried out in the presence of 500 mM H2O2, 10 mM Fe2+, and 20 mM Glu at pH 5 could be shown. The efficiency of this modified Fenton's system for mass destruction of BTEX in contaminated water was measured to estimate the impact of the major process variables that include initial concentrations of soluble Fe, H2O2, Glu (as metal chelating agent), and reaction time.
Phenanthrene Removal from Aqueous Solution on Sesame Stalk‐based Carbon
Authors: Kong Huoliang , He Jiao , Wu Huifang , Wu Hao , Gao Yanzheng 
Published: April 2012

AbstractThis work explored the performance of sesame stalk‐based carbon prepared at different carbonization temperatures and activated by potassium hydroxide in the removal of phenanthrene from an aqueous solution. At a carbon concentration of 10 mg/32 mL and a carbonization temperature of 700°C, the removal efficiency of phenanthrene approached 100%. Furthermore, with the presence of acenaphthene and naphthalene as co‐contaminants, the removal efficiency of phenanthrene by the prepared carbon was 99.60%, which was comparable to that by the commercial carbon. Hydrophobic interactions influenced phenanthrene removal, and partitioning appeared to be the dominant mechanism for phenanthrene removal from aqueous solution by sesame stalk‐based carbon. The results obtained from this work should provide insight into the reuse of agricultural residues, and also suggest a new avenue for the removal of polycyclic aromatic hydrocarbons from contaminated water utilizing carbon prepared from agricultural residue.
Comparative Study of Flavins Binding with Human Serum Albumin: A Fluorometric, Thermodynamic, and Molecular Dynamics Approach
Authors: Sengupta Abhigyan , Sasikala Wilbee D. , Mukherjee Arnab , Hazra Partha 
Published: April 2012

AbstractFlavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) are derivatives of riboflavin (RF), a water‐soluble vitamin, more commonly known as vitamin B2. Flavins have attracted special attention in the last few years because of the recent discovery of a large number of flavoproteins. In this work, these flavins are used as extrinsic fluorescence markers for probing the microheterogeneous environment of a well‐known transport protein, human serum albumin (HSA). Steady‐state and time‐resolved fluorescence experiments confirm that both FMN and FAD bind to the Sudlow’s site‐1 (SS1) binding pocket of HSA, where Trp214 resides. In the case of RF, a fraction of RF molecules binds at the SS1, whereas the major fraction of RF molecules remains unbound or surface bound to the protein. Moreover, flavin(s)–HSA interactions are monitored with the help of isothermal titration calorimetry, which provides free energy, enthalpy, and entropy changes of binding along with the binding constants. The molecular picture of binding interaction between flavins and HSA is well explored by docking and molecular dynamics studies.
Audio quality in lossy networks for media‐specific forward error correction schemes
Authors: Inoie A. 
Published: April 2012

SUMMARYA media‐specific forward error correction (FEC) is used to prevent the loss of audio packets due to noise or interference in the transmission and buffer overflow in the router. In this FEC scheme, for nth packet, the redundant data are added in (n + ϕ)th packet where ϕ is called the offset. In this paper, we consider an M/M/1/K queueing system and derive some simple expressions for calculating the audio qualities of the aforementioned schemes. We analytically and numerically show some counter‐examples and characteristics for these FEC schemes by using our analytical model. Copyright © 2012 John Wiley & Sons, Ltd.
An Improved and Safer Synthesis of (R)‐ and (S)‐4,4′‐Diaminomethyl‐BINAP
Authors: Dayoub Wissam , Favre‐Reguillon Alain , Berthod Mikael , Jeanneau Erwann , Mignani Gérard , Lemaire Marc 
Published: April 2012

Abstract(R)‐ and (S)‐4,4′‐diaminomethyl‐BINAP were prepared in three steps from enantiomerically pure BINAPO in a global yield of 52 %. A regioselective bromination of BINAPO with NBS in HMimPF6 gave the desired 4,4′‐dibromo‐BINAPO in quantitative yield, and the recyclability of the ionic liquid was demonstrated. Copper cyanide cyanation of 4,4′‐dibromo‐BINAPO gave the 4,4′‐dicyano‐BINAPO in 70 % yield. Both enantiomers were characterized by NMR spectroscopy and HPLC analysis, and the structures were confirmed by X‐ray crystallography. The cyano and phosphane oxide groups of the resulting 4,4′‐dicyano‐BINAPO were reduced in one step to the corresponding 4,4′‐diaminomethyl‐BINAP by using tetramethyldisiloxane/Ti(OiPr)4 in 75 % yield.
Quantification of vertical water fluxes in the vadose zone using particle‐size distribution and pedology‐based approaches to model soil heterogeneities
Authors: Ounaïes Sana , Schäfer Gerhard , Trémolières Michèle 
Published: April 2012

AbstractOne‐dimensional flow simulations were conducted at four locations of the shallow alluvial aquifer of the upper Rhine River (at the Erstein polder) to quantify the time‐dependent moisture distribution, the water flux and the water volume infiltrated in the unsaturated zone as a function of soil heterogeneities during a five‐day‐long flooding event. Three methods of estimating the hydraulic parameters of soil in the vadose zone were tested. They are based on the following: (1) experimental data, (2) soil particle‐size distribution and (3) pedology information on soils. Water fluxes calculated from modelling approaches 2 and 3 were compared with those of the experiment‐based values and the effect of these differences on the arrival time and velocity of water at the water table were analysed. Major differences in water fluxes were found among the methods of estimating the hydrodynamic parameters. At the Terrace location, the groundwater recharge predicted using soil data from methods 1 and 2 are approximately 4500 and 2400 mm, respectively. Flow simulations using soil data and the experiment‐based method show the highest velocities of infiltrating water at the soil surface and largest volume of groundwater infiltration but result in the lowest centres of the moisture content mass. The results obtained using soil data based on the pedological method are similar to those calculated using soil parameters based on the particle‐size distribution of extracted soil samples. Water pressure profiles calculated on Terrace and Channel location, 3 and 7 days after the inundation event agreed reasonably well with those observed when using hydrodynamic parameters from the experiment‐based method. However, the flow model using the pedology‐based parameters largely underestimates the time needed to achieve hydrostatic conditions of the soil water profile once water flooding at the soil surface stops. This can be mainly attributed to the low values of estimated van Genuchten parameter α. Copyright © 2012 John Wiley & Sons, Ltd.
Analyzing the catalytic processes of immobilized redox enzymes by vibrational spectroscopies
Authors: Sezer Murat , Millo Diego , Weidinger Inez M. , Zebger Ingo , Hildebrandt Peter 
Published: April 2012

AbstractAnalyzing the structure and function of redox enzymes attached to electrodes is a central challenge in many fields of fundamental and applied life science. Electrochemical techniques such as cyclic voltammetry which are routinely used do not provide insight into the molecular structure and reaction mechanisms of the immobilized proteins. Surface‐enhanced infrared absorption (SEIRA) and surface‐enhanced resonance Raman (SERR) spectroscopy may fill this gap, if nanostructured Au or Ag are used as conductive support materials. In this account, we will first outline the principles of the methodology including a description of the most important strategies for biocompatible protein immobilization. Subsequently, we will critically review SERR and SEIRA spectroscopic approaches to characterize the protein and active site structure of the immobilized enzymes. Special emphasis is laid on the combination of surface‐enhanced vibrational spectroscopies with electrochemical methods to analyze equilibria and dynamics of the interfacial redox processes. Finally, we will assess the potential of SERR and SEIRA spectroscopy for in situ investigations on the basis of the first promising studies on human sulfite oxidase and hydrogenases under turnover conditions. © 2012 IUBMB IUBMB Life, 2012