bluuebunny/crossref_metadata_2025 huggingface dataset:
Herbicidas alternativos para o controle de Raphanus raphanistrum L. resistente ao herbicida metsulfurom metílico
Authors: Costa Leandro Oliveira da , Rizzardi Mauro Antônio
Published: April 2014

O controle de plantas daninhas dicotiledôneas, em culturas de inverno, é realizado basicamente com herbicidas inibidores da enzima ALS. O uso intensivo desses herbicidas em áreas cultivadas com trigo tem proporcionado pressão de seleção nas populações de Raphanus raphanistrum resultando em biótipos resistentes a esses herbicidas. Objetivou-se com esse trabalho determinar a existência de resistência cruzada e múltipla aos herbicidas inibidores de ALS e alternativas de controle químico dessa planta daninha resistente ao metsulfurom metílico. Os tratamentos resultaram da combinação de dois biótipos de R. raphanistrum resistente (biótipo R) e suscetível (biótipo S), com 12 herbicidas: glifosato, atrazina, bentazona, 2,4-D, sulfometurom metílico + clorimurom etílico, clorimurom etílico, cloransulam metílico, iodosulfurom, nicossulfurom, imazetapir, metsulfurom metílico, imazapic + imazapir e mais um tratamento controle sem aplicação. Aplicou-se a dose recomendada de cada herbicida, para o controle da espécie, no estádio de desenvolvimento de 3 a 4 folhas verdadeiras. Foram analisados a eficiência de controle e redução de massa seca da parte aérea. O biótipo S foi suscetível aos herbicidas inibidores da ALS e aos demais mecanismos de ação testados. O biótipo R apresentou resistência cruzada aos grupos químicos imidazolinonas, sulfoniluréias e triazolpirimidinas variando o grau de sensibilidade entre esses grupos. O biótipo R não foi diagnosticado com resistência múltipla, e os herbicidas glifosato, bentazona, atrazina e 2,4-D demonstraram serem eficazes no seu controle, podendo utilizá-los como alternativas para o manejo químico dessa planta daninha.
Antimicrobial Surfaces
Authors: Gratzl Guenther , Paulik Christian , Lackner Maximilian
Published: April 2014

Biofouling, the attachment of biological material onto surfaces, is a pervasive and costly problem affecting marine equipment, membrane‐based systems, medical devices, textiles, food packing, and other systems and devices. The attachment of biological material to surfaces is often attributed to an initial microbial settling and the subsequent formation of a microbial biofilm on a surface. Antimicrobial agents have been used to prevent or reduce biofilm formation and are effective if their concentration is sufficiently high; however, biocides are toxic substances that affect the surrounding environment.

This article provides an overview of the most important antimicrobial agents, technologies, and recent developments aimed at preventing biofouling. It focuses on antimicrobial surfaces and their current and prospective use, proposed mechanisms of action, and applications.
Constitutional Dynamic Chemistry
Authors: Hu Lei , Schaufelberger Fredrik , Timmer Brian J. J. , Flos Marta Abellán , Ramström Olof
Published: April 2014

The concept of dynamic chemistry enables efficient generation of complex systems and in situ organization of optimal constituents in response to thermodynamic and kinetic selection pathways. In this review, the concept at the constitutional level is described, highlighting some of the most important developments in the area. Special emphasis is put on three major areas: 1) Dynamic generation/amplification of bioactive substances; 2) Dynamic approaches to complex molecular architectures; and 3) Design and engineering of new dynamic materials.
Protective Clothing
Authors: Bickford Mickey
Published: April 2014

Skin exposure to chemicals in the workplace is a significant health and safety issue. Protective clothing plays a major role in the prevention of chemicals causing damage to skin, and vital organs through blood. The first consideration is to determine if a workplace can be controlled by changes in the job flow, ventilation, etc. If not, then protective clothing must be considered. Hazard assessments of the workplace will determine what type of material for the clothing is necessary. Not all materials behave the same so individual tests must be done. Levels of protection according to the EPA are discussed. Types of clothing used are full ensembles, aprons, disposable protection, gloves, eye wear, boots, and respiratory gear. Many of the garments are made from polymers and natural rubber. ISO, ASTM, and NFPA standards are given.

Some improvements in protection such as respiratory equipment that allows only certain gases such as oxygen to pass through, one‐size fits all with adjustments for the individual, and the use of new materials that reduce heat stress.
High‐speed video and electromagnetic analysis of two natural bipolar cloud‐to‐ground lightning flashes
Authors: Saraiva A. C. V. , Campos L. Z. S. , Williams E. R. , Zepka G. S. , Alves J. , Pinto O. , Heckman S. , Buzato T. S. , Bailey J. C. , Morales C. A. , Blakeslee R. J.
Published: April 2014

High‐speed video records of two bipolar cloud‐to‐ground flashes were analyzed in detail. They both began with a single positive return stroke that was followed by more than one subsequent weak negative stroke. Due to the elevated cloud base height of its parent thunderstorm, the preparatory processes of each subsequent negative stroke were documented optically below cloud base. In the first event (Case 1) it was observed that all four subsequent negative strokes were initiated by recoil leaders that retraced one horizontal channel segment previously ionized by the positive leader. Those recoil leaders connected to the original vertical channel segment and propagated toward ground, producing four subsequent strokes that had the same ground contact point as the original positive discharge. The second event (Case 2), in contrast, presented 15 subsequent strokes that were initiated by recoil leaders that did not reach the original channel of the positive stroke. They diverged vertically toward ground, making contact approximately 11 km away from the original positive strike point. These results constitute the first optical evidence that both single‐ and multiple‐channel bipolar flashes occur as a consequence of recoil leader activity in the branches of the initial positive return stroke. For both events their total channel length increased continuously at a rate of the order of 104 m s−1, comparable to speeds reported for typical positive leaders.
A spherical harmonic model of the lithospheric magnetic field of Mars
Authors: Morschhauser A. , Lesur V. , Grott M.
Published: April 2014

We present a model of the lithospheric magnetic field of Mars which is based on Mars Global Surveyor orbiting satellite data and represented by an expansion of spherical harmonic (SH) functions up to degree and order 110. Several techniques were applied in order to obtain a reliable and well‐resolved model of the Martian lithospheric magnetic field: A modified Huber‐Norm was used to properly treat data outliers, the mapping phase orbit data was weighted based on an a priori analysis of the data, and static external fields were treated by a joint inversion of external and internal fields. Further, temporal variabilities in the data which lead to unrealistically strong anomalies were considered as noise and handled by additionally minimizing a measure of the horizontal gradient of the vertically down internal field component at surface altitude. Here we use an iteratively reweighted least squares algorithm to approach an absolute measure (L1 norm), allowing for a better representation of strong localized magnetic anomalies as compared to the conventional least squares measure (L2 norm). The resulting model reproduces all known characteristics of the Martian lithospheric field and shows a rich level of detail. It is characterized by a low level of noise and robust when downward continued to the surface. We show how these properties can help to improve the knowledge of the Martian past and present magnetic field by investigating magnetic signatures associated with impacts and volcanoes. Additionally, we present some previously undescribed isolated anomalies, which can be used to determine paleopole positions and magnetization strengths.
Insights into the physical processes controlling correlations between snow distribution and terrain properties
Authors: Anderson Brian T. , McNamara James P. , Marshall Hans‐Peter , Flores Alejandro N.
Published: April 2014

This study investigates causes behind correlations between snow and terrain properties in a 27 km2 mountain watershed. Whereas terrain correlations reveal where snow resides, the physical processes responsible for correlations can be ambiguous. We conducted biweekly snow surveys at small transect scales to provide insight into late‐season correlations at the basin scale. The evolving parameters of transect variograms reveal the interplay between differential accumulation and differential ablation that is responsible for correlations between snow and terrain properties including elevation, aspect, and canopy density. Elevation‐induced differential accumulation imposes a persistent source of varariabity at the basin scale, but is not sufficient to explain the elevational distribution of snow water equivalent (SWE) on the ground. Differential ablation, with earlier and more frequent ablation at lower elevations, steepens the SWE‐elevation gradient through the season. Correlations with aspect are primarily controlled by differences in solar loading. Aspect related redistribution of precipitation by wind, however, is important early in the season. Forested sites hold more snow than nonforested sites at the basin scale due to differences in ablation processes, while open areas within forested sites hold more snow than covered areas due to interception. However, as the season progresses energetic differences between open and covered areas within forested sites cause differences induced by interception to diminish. Results of this study can help determine which accumulation and ablation processes must be represented explicitly and which can be parameterized in models of snow dynamics.
Biological and Biomedical Aspects of Metal Phenolates
Authors: Ming Li‐June
Published: April 2014

The phenol functionality is involved in diverse biological processes and functions, serving as a proton donor and as a metal‐binding ligand. It is commonly found in many biochemicals (such as siderophores and the amino acids tyrosine and tryptophan), pharmaceuticals (including antibiotics, metal‐chelating agents, and diagnostic agents), and natural products (such as polyphenols, flavonoids, and salicylic acid). In association with other functional groups, the phenol moiety forms various types of metal‐binding sites of diverse structures and functions, for example, for iron binding and transport, in enzymes for oxygenation of substrates, and for biotransformation of aromatic compounds. Many environmentally hazardous aromatic compounds such as bisphenol A, PCB, and DDT can be degraded by tyrosinate(phenolate)‐containing metalloenzymes from microorganisms, which provides a clue for bioremediation of these toxic substances. Moreover, the phenol‐containing wet‐adhesive byssal proteins from some clams and mussels has stimulated further development of adhesive materials for medical and other applications; and the study of binding of transferrin with nanoparticles affords better understanding of protein–mineral interfacial interactions. In addition to these naturally occurring metal‐phenolate centers, there are many metal complexes of phenol and derivatives that exhibit various catalytic activities and serve as structural and/or functional model systems for tyrosinate‐containing metalloproteins.
Coordination Chemistry and Applications of Phenolic Calixarene–metal Complexes
Authors: Li Yuanzhou , Zhao Ke‐Qing , Redshaw Carl , Ortega Bernat A. Martínez , Nuñez Alane Y. , Hanna Tracy A.
Published: April 2014

Calixarenes are a class of macrocyclic phenols that range in size from calix[4]arene, containing four linked phenols, to calix[20]arene. This chapter focuses on metallocalixarenes that fall into the category of metal phenolates, that is, metallocalixarenes in which the metal is bound directly to the phenolic moiety. The coordination chemistry of calixarene from 2001–2012 is reviewed, divided by groups in the periodic table;s‐block, transition, heavy main group (p‐block), and rare earth metallocalixarenes. Synthesis, structural chemistry, and applications are discussed.
Iron Acyl Complexes
Authors: Liebmann Diana , Zastrow Marc , Rück‐Braun Karola
Published: April 2014

This chapter covers a selection of acyl complexes and synthetic applications published within the past two decades. Iron acyl complexes are useful building blocks for organic synthesis. This survey covers recent synthetic applications of a selection of acyl complexes published within the last two decades. Herein, acyl complexes derived from carbonyl iron reagents are discussed, besides cyclopentadienyl dicarbonyl iron compounds, their phosphine‐substituted chiral‐at‐iron derivatives and diiron acyl complexes. This chapter has been organized according to the above classification with additional ligands and their reactivity, for example allyl, dienes.
Iron‐promoted Reduction Reactions
Authors: Nagashima Hideo , Sunada Yusuke , Nishikata Takashi , Chaiyanurakkul Arada
Published: April 2014

Iron‐promoted reduction reactions are described from the standpoint of the catalyst design. Catalysis of three well‐defined precatalysts is the first topic; iron complexes having PNNP ligands, Shvo‐type complexes, and pincer compounds are active towards catalytic hydrogenation and transfer hydrogenation of ketones. The reduction mechanisms are in line with the concept of Noyori's metal‐ligand bifunctional catalysis, in which the ligand plays a key role in the hydrogenation of the carbonyl function. The redox‐active ligands in iron‐catalyzed hydrogenation and hydrosilylation of alkenes and alkynes provide other important aspects contributing to the catalyst design. In particular, redox properties of bis(imino)pyridine ligands assist the activation of H–H and H–Si bonds in molecular hydrogen and organohydrosilanes leading to efficient hydrogenation and hydrosilylation of alkenes. Reduction reactions mediated by iron compounds, which include catalytic hydrogenation, transfer hydrogenation, and hydrosilylation, are overviewed from organic synthesis, which is promoted by a mixture of iron salts and ligands, ill‐defined catalyst precursors, and nanoparticles. From these, the possible catalyst design of iron is discussed.
Recent Advances of Structural Chemistry of Organoselenium and Organotellurium Compounds
Authors: Nakanishi Waro , Hayashi Satoko , Hashimoto Masato , Arca Massimiliano , Aragoni Maria Carla , Lippolis Vito
Published: April 2014

The recent advances of structural chemistry of organoselenium and organotellurium compounds are reviewed. The basic concepts of structural chemistry of the compounds are well summarized in Chapter 3 of Volume 1 in this series. About 9,000 structures for the compounds have been reported since then, therefore only selected results can be discussed here. Such compounds are expected to contain at least one CE (E = Se or Te) bond, although those with no CE bonds are also discussed, as necessary. Compounds containing CE (E = Se and Te) are discussed in some detail. Structures of unstable and/or reactive species are explained in detail, which are stabilized by the formation of dimers or higher oligomers or using large protecting groups. Bis‐selenides and bis‐tellurides and the derivatives at the naphthalene 1,8‐positions and the related systems are discussed in detail. The compounds containing hypervalent interactions are also discussed in detail. The idea is applied to the intramolecular and intermolecular linear interactions in crystals. In this connection, the extended hypervalent interactions are also explained in detail for the linear interactions longer than three, exemplified by typical cases and unique cases in crystals.
Selenium and Tellurium Heterocycles
Authors: Logan Margaret E. , Lang Meredith A. , Detty Michael R.
Published: April 2014

Synthetic pathways leading to tellurium‐ and selenium‐containing heterocycles are summarized for the period 1995 to the present. In addition, the utility of various tellurium‐ and selenium‐containing heterocycles are summarized. Primarily, the synthesis of tellurium‐ and selenium‐containing heterocycles of five‐ and six‐membered rings are described with various degrees of unsaturation, as well as their benzo‐fused analogues. In particular, the syntheses of selenophenes , tellurophenes and their mono‐ and dibenzo‐fused analogues are described. Similarly, syntheses of tellurazoles, selenazoles, telluradiazoles, selenadiazoles and their benzo‐fused analogues are described. Among the six‐membered rings, synthetic routes to telluropyrans and selenopyrans and their benzo analogues are described. Further degrees of unsaturation provide the telluropyrylium and selenopyrylium compounds and their benzo‐ and dibenzo‐fused analogues. Synthetic routes to chalcogenopyrylium compounds, chalcogenorosamine compounds and chalcogenorhodamine compounds are described and some of the uses of these materials are also provided. A review of synthetic routes to the core‐modified porphyrins—21‐chalcogenoporphyrins and 21,23‐dichalcogenoporphyrins—is also provided. Porphyrin‐like molecules with an expanded structure of five or six‐membered rings in the porphyrin core are also reviewed.
Supramolecular Architectures Based on
M
(lone pair)…π(arene) Interactions for
M

S
e and
T
e
Authors: Caracelli Ignez , Haiduc Ionel , Zukerman‐Schpector Julio , R. T. Tiekink Edward
Published: April 2014

An overview of intermolecular interactions occurring between each of selenium and tellurium centers, in both the +II and +IV oxidation states (i.e. with two and one available lone pairs) with arene rings, that is M(lone pair) ⋯ π(arene) interactions, in their crystal structures is presented. These M(lone pair) ⋯ π(arene) interactions are proven to be important in stabilizing supramolecular architectures in their respective solid‐state structures. Thus, when operating in isolation of other intermolecular forms of association, for example hydrogen bonding and secondary interactions, M(lone pair) ⋯ π(arene) interactions usually lead to either zero‐ and one‐dimensional supramolecular aggregation patterns often sustained by one donor and one acceptor M(lone pair) ⋯ π(arene) interaction per molecule. Intriguingly, examples are also presented for two‐ and even three‐dimensional architectures stabilized by this supramolecular synthon alone, indicating that some molecules, often with higher nuclearity, can form multiple M(lone pair) ⋯ π(arene) interactions. Rarely, when the selenium or tellurium center is in the +II oxidation state does the element form two such interactions. In conclusion, it is suggested that any complete analysis of any selenium‐ or tellurium‐containing crystal structure should include an evaluation for M(lone pair) ⋯ π(arene) interactions.
Synthesis of Biologically Relevant Small Molecules Containing Selenium. Part C. Miscellaneous Biological Activities
Authors: Braga Antonio L. , Rafique Jamal
Published: April 2014

Organoselenium compounds are known as antioxidants, antithyroid, antinociceptive, antidepressant, thioredoxin reductase (TrxR) mimetic agents with a variety of protective behaviors (e.g. cardioprotective, neuroprotective and hepatoprotective). In addition. they can be used as virueides, bactericides, fungicides, cytokine inducers and immunomodulators. The chemical and biological activity of organose leniumcompounds is discussed herein.

The strategies and methods for the preparation of biologically relevant small molecules containing selenium are reviewed in this chapter. The unique redox properties of selenium confer catalytic activity to organoselenium compounds and influence their biological properties as well as the methods selected for their preparation. The approaches available to obtain organoselenium compounds, including reaction of elemental selenium or diselenides with different types of carbanions or reaction of organic electrophiles with selenolate anions generated by different methods, are disclosed in this chapter.
Heteroatom‐substitued Dioxetanes and their Emerging Biomedical Applications
Authors: NKEPANG GREGORY , YOU YOUNGJAE
Published: April 2014

Heteroatom‐substituted dioxetanes are one subclass of dioxetanes that have at least one heteroatom (such as O, S, N) at its two carbons of dioxetane structures. These are readily formed from the [2+2] cycloaddition reaction of heteroatom‐substituted alkenes and singlet oxygen (1O2). Due to their unique characteristics, such as chemiluminescence and spontaneous cleavage, heteroatom‐substituted dioxetanes have been used for a number of biomedical applications, for example biomedical analyses and light‐controlled drug release. A number of review papers and book chapters have been published for the biomedical analyses of chemiluminescence. However, no comprehensive review or book chapter for the applications to light‐controlled drug release have yet been published, although there have been very significant and interesting advances in the field in the last couple of years. In this chapter, we focus mainly on a new and exciting application of dioxetanes for light‐controlled drug release. In the latter part of this section, we also introduce briefly another new interesting application of dioxetane chemistry for hydrogen peroxide (H2O2) imaging.
1,2‐Dioxatrisulfane (thiaperoxide) intermediates in type I and II photooxygenation reactions
Authors: CLENNAN EDWARD L.
Published: April 2014

This review focuses on a discussion of labile metastable sulfur‐based peroxides (persulfoxides‐R2S+OO−; 3‐membered SOO ring thiadioxiranes‐c‐R2SO2; hydroperoxy sulfonium ylides‐R(R′CH)S+OO−; and, peroxy sulfuranes‐R2S(OR′)OOR′′) that have been observed or implicated in Type I and II photooxygenation reactions. Evidence for formation and computational structures of these novel intermediates is presented.
Peroxide Explosives
Authors: Klapötke Thomas M. , Wloka Thomas
Published: April 2014

Triacetone triperoxide (TATP) is formed from acetone in sulfuric acid solution when acted upon hydrogen peroxide. Like most other organic peroxides TATP has very high impact, friction and thermal sensitivity. TATP displays the properties of a primary explosive. For this reason and because of its tendency to sublime it is not used in practice (apart from terrorist and suicide bomber activities). Because of the use of TATP by terrorists, a reliable and fast detection of this material is desirable. In addition to conventional analytical methods such as mass spectrometry and UV (ultra violet) spectroscopy specially trained explosive detection dogs (EDD) play an important role in the detection of organic peroxides. Typical organic peroxides, which have or may be used by terrorists, so‐called homemade explosives (HMEs) discussed in this chapter are: TATP (triacetone triperoxide), HMTD (hexamethylene triperoxide diamine), MEKP (methyl ethyl ketone peroxide) and DADP (diacetone diperoxide).
The Use of Hydrogen Peroxide for Disinfection and Sterilization Applications
Authors: McDonnell Gerald
Published: April 2014

Hydrogen peroxide is a widely used antimicrobial chemical. It is used in both liquid and gas form for preservative, disinfection and sterilization applications. Its advantages include its potent and broad spectrum antimicrobial activity, flexibility in use, and safety profile in comparison to other microbiocides. Hydrogen peroxide has been shown to be effective against all forms of microorganisms, including dormant forms with known high resistance such as bacterial spores and protozoal cysts, and also infectious proteins such as prions depending on the specific use of the chemical. It also has advantages with regard to its toxicity and environmental profile. However, overall, the effective and safe use of hydrogen peroxide depends on the way it is used, in particular the concentration. In aqueous form it is used in solution with water directly as a preservative, in products as a preservative or on the skin, including in wounds, and on inanimate surfaces. Recent technology advances have been made in the formulation of peroxide with other chemicals to enhance the antimicrobial activity at lower target concentrations of the active agent. Hydrogen peroxide gas is also widely used for disinfection and sterilization. The gas form is particularly effective in comparison liquid forms and at lower concentrations. Hydrogen peroxide gas processes have become popular alternatives to other chemical and physical based antimicrobial methods due to its rapid efficacy, low temperature, compatibility with surface materials and limited toxicity concerns. The mechanism of action of hydrogen peroxide is not fully understood and is associated with its oxidation activity. The oxidation of the various molecules that constitute microorganisms will lead to significant disruptions in structure/function and the loss of viability or infectivity. Despite this generalization, liquid preparations, formulations and the gas form of hydrogen peroxide can show remarkable differences in their antimicrobial effects, such as their attack on proteins, nucleic acids, and lipids. The general mechanisms of action of hydrogen peroxide significantly reduce any risk of the development of resistance to the biocide over time, unlike many other types of anti‐infective drugs or biocides. Microbial resistance to peroxide is primarily due to the various natural differences observed in the growth and survival of microorganisms but can be overcome by the right process and application with hydrogen peroxide‐containing products. The many benefits in the use of liquid and gas hydrogen peroxide for antimicrobial applications make it attractive for future and optimal developments with this microbiocide.
Linear Accelerators
Authors: Jameson Robert , Bisognano Joseph , Lapostolle Pierre
Published: April 2014

Linear accelerators, in which particles are accelerated along a straight path, are a fundamental tool for a perhaps surprisingly wide variety of practical and research applications that affect our daily lives, as a source of energetic particles in equipment for medical, biological, and industrial applications, including dental X‐rays, industrial irradiation, radiotherapy, medical tool sterilization, food conservation, and baggage inspection, and provide intense beams of neutrons or photons for use in condensed matter, materials, and biological sciences and applications. In the future, LINACs will enable methods to deal with radioactive waste and other societally important applications. The general principles, brief history, and overview of the various types of linear accelerators are outlined in this chapter.
Nuclear Structure
Authors: Jolie Jan
Published: April 2014

The basic properties of atomic nuclei are reviewed. Experimental measurements of nuclear masses give access to the nuclear binding energies and are essential to understand nuclear radioactivity and basic properties of atomic nuclei via the semiempirical mass formula. The presence of charges in the atomic nuclei leads to the possibility to measure the nuclear charge distribution. Emphasis is put on the electromagnetic properties of nuclear excitations allowing the determination of several nuclear moments of states and of electromagnetic transition rates in between these states. Following an overview of the observed properties of excited states in atomic nuclei, four nuclear models used to describe the structure of the atomic nucleus are introduced. They are the spherical and deformed shell models, the collective model, and the interacting boson model.
Exotic Nuclear Beam Facilities
Authors: Geissel Hans , Huyse Mark , Münzenberg Gottfried , Van Duppen Piet
Published: April 2014

The knowledge of exotic nuclei properties is essential for the understanding of the strong interaction and the element synthesis in the cosmos. Exotic nuclides are short lived and therefore, cannot be found on Earth but are still produced in stars. To study such atomic nuclei, one has to produce them with nuclear reactions in the laboratory and to separate them with special tools, from all the inevitable abundant background. The production and separation of these exotic nuclear beams can be performed with in‐flight or isotope separation on line facilities or hybrid systems of these two main scenarios. An exotic nuclear beam facility consists mainly of a combination of the production and the separation part as well as a post‐acceleration unit for the case that the experiment needs beams with kinetic energies and emittances different from that what the separator can provide. The challenge to investigate exotic nuclei is that they are characterized by very low production cross sections and short half‐lives. Different reactions to create exotic nuclei, and the physics and techniques of modern separation methods are discussed. We present the recent progress made in studying exotic nuclei by new accelerator developments, powerful separators combined with high‐resolution spectrometers and storage devices, and efficient detector systems. This chapter ends with the description of some recent discoveries with exotic nuclei and the motivation for the next‐generation facilities.
Superheavy Nuclei
Authors: Hofmann Sigurd
Published: April 2014

The existence of nuclei at the limits of stability is determined by nuclear structure. The nuclear shell model, which effectively describes nuclear properties and the underlying shell structure all over the chart of nuclei, predicts the next closed shells or subshells beyond the double magic

208
Pb

at proton numbers

Z

 = 114, 120, or 126, and at neutron number

N

 = 184. Although the strength of the shells is difficult to calculate, an increased stability is expected for nuclei having these numbers of protons and neutrons. Experiments performed at various major laboratories were aiming to produce these “superheavy nuclei.” Described are the results of these experiments covering reaction studies and measurements of the decay properties of the nuclei produced. A comparison of the data with predictions of theoretical models reveals an increased stability for deformed nuclei at

Z

 = 108 and

N

 = 162, and for spherical nuclei having proton numbers

Z

 = 114–118 and neutron numbers approaching

N

 = 184. It is shown that, in general, the theoretical predictions are confirmed by experiments, although details of the structure of the island of superheavy nuclei remain to be explored.
The Proton
Authors: Caldwell Allen
Published: April 2014

This chapter describes the historical development and current state of knowledge concerning the proton. The understanding of the proton has gone through several revolutions in the last 100 years, and we start with a short review of this history. The central part of the text then describes the proton in terms of its constituents and the current state of knowledge on this structure is outlined. Although we have acquired a wealth of knowledge concerning the proton, many fascinating research questions remain. As shown at the end of the chapter, very different pictures of the basic physics arise depending on the frame of reference one chooses to describe the physics.
Fool Me Twice: The Consequences of Reading (and Rereading) Inaccurate Information
Authors: Jacovina Matthew E. , Hinze Scott R. , Rapp David N.
Published: April 2014

Readers frequently encounter inaccuracies in texts that contradict what they should know to be true. The current project examined readers' moment‐by‐moment processing of inaccuracies and whether any difficulty with such material is reduced when readers are already familiar with accurate versions of that content. In two experiments, participants read stories that either accurately or inaccurately described the outcome of a well‐known historic event. Preceding story contexts supported accurate outcomes or introduced suspense to create uncertainty about outcome likelihoods. During initial readings, participants took longer to read inaccurate than accurate outcomes. But this difficulty was substantially reduced when suspenseful contexts called into question the likelihood of well‐known outcomes. Similar reading patterns emerged when participants read the exact same material after week‐long and 5‐minute delays. These results indicate that biasing contexts can influence readers' processing of inaccuracies for even familiar events. Rereading proves insufficient for encouraging reliance on accurate prior knowledge. Copyright © 2014 John Wiley & Sons, Ltd.
Wear‐ and Corrosion‐Resistant Boride‐Based Coatings Obtained through Thermal Diffusion CVD Processing
Authors: Medvedovski Eugene , Chinski﻿ Fred A. , Stewart Jim
Published: April 2014

Chemical vapor deposition (CVD) boride coatings obtained through thermal diffusion of boron into metallic base of engineering components provide significant improvement of wear and corrosion resistance, integrity and service life of the components in several times. Thermal diffusion process and coating quality are defined by the batch composition providing the boron deposition and diffusion, temperature and time of the process, type of metallic base and its surface quality, and engineering design of the CVD process system. The obtained coatings with thicknesses of 50–250 up to 300–400 µm (depending on the application) are uniform and dense with consistent “saw‐tooth” structures (for carbon steels) through the entire surface of the components with no delamination issues. Wear test studies demonstrated the coatings’ adequate performance defined by high hardness and specific morphology of the coatings.
A Molecular Approach to Self‐Supported Cobalt‐Substituted ZnO Materials as Remarkably Stable Electrocatalysts for Water Oxidation
Authors: Pfrommer Johannes , Lublow Michael , Azarpira Anahita , Göbel Caren , Lücke Marcel , Steigert Alexander , Pogrzeba Martin , Menezes Prashanth W. , Fischer Anna , Schedel‐Niedrig Thomas , Driess Matthias
Published: April 2014

In regard to earth‐abundant cobalt water oxidation catalysts, very recent findings show the reorganization of the materials to amorphous active phases under catalytic conditions. To further understand this concept, a unique cobalt‐substituted crystalline zinc oxide (Co:ZnO) precatalyst has been synthesized by low‐temperature solvolysis of molecular heterobimetallic Co4−xZnxO4 (x=1–3) precursors in benzylamine. Its electrophoretic deposition onto fluorinated tin oxide electrodes leads after oxidative conditioning to an amorphous self‐supported water‐oxidation electrocatalyst, which was observed by HR‐TEM on FIB lamellas of the EPD layers. The Co‐rich hydroxide‐oxidic electrocatalyst performs at very low overpotentials (512 mV at pH 7; 330 mV at pH 12), while chronoamperometry shows a stable catalytic current over several hours.
Formation of High‐Valent Iron–Oxo Species in Superoxide Reductase: Characterization by Resonance Raman Spectroscopy
Authors: Bonnot Florence , Tremey Emilie , von Stetten David , Rat Stéphanie , Duval Simon , Carpentier Philippe , Clemancey Martin , Desbois Alain , Nivière Vincent
Published: April 2014

Superoxide reductase (SOR), a non‐heme mononuclear iron protein that is involved in superoxide detoxification in microorganisms, can be used as an unprecedented model to study the mechanisms of O2 activation and of the formation of high‐valent iron–oxo species in metalloenzymes. By using resonance Raman spectroscopy, it was shown that the mutation of two residues in the second coordination sphere of the SOR iron active site, K48 and I118, led to the formation of a high‐valent iron–oxo species when the mutant proteins were reacted with H2O2. These data demonstrate that these residues in the second coordination sphere tightly control the evolution and the cleavage of the OO bond of the ferric iron hydroperoxide intermediate that is formed in the SOR active site.
Enzyme‐Mediated Site‐Specific Bioconjugation of Metal Complexes to Proteins: Sortase‐Mediated Coupling of Copper‐64 to a Single‐Chain Antibody
Authors: Paterson Brett M. , Alt Karen , Jeffery Charmaine M. , Price Roger I. , Jagdale Shweta , Rigby Sheena , Williams Charlotte C. , Peter Karlheinz , Hagemeyer Christoph E. , Donnelly Paul S.
Published: April 2014

The enzyme‐mediated site‐specific bioconjugation of a radioactive metal complex to a single‐chain antibody using the transpeptidase sortase A is reported. Cage amine sarcophagine ligands that were designed to function as substrates for the sortase A mediated bioconjugation to antibodies were synthesized and enzymatically conjugated to a single‐chain variable fragment. The antibody fragment scFvanti‐LIBS targets ligand‐induced binding sites (LIBS) on the glycoprotein receptor GPIIb/IIIa, which is present on activated platelets. The immunoconjugates were radiolabeled with the positron‐emitting isotope 64Cu. The new radiolabeled conjugates were shown to bind selectively to activated platelets. The diagnostic potential of the most promising conjugate was demonstrated in an in vivo model of carotid artery thrombosis using positron emission tomography. This approach gives homogeneous products through site‐specific enzyme‐mediated conjugation and should be broadly applicable to other metal complexes and proteins.
Creating Different Versions of Life: Talking About Problems with Children and their Parents
Authors: Lundby Geir
Published: April 2014

When working with families, many parents have told us that externalizing the problem is the single most important thing they experienced in our work together. This paper describes how externalizing conversations and double‐story development can assist children and their parents talk about problems and create different versions of life. Examples from narrative family therapy conversations with two Norwegian families are included.
Creating Stories of Hope: A Narrative Approach to Illness, Death and Grief
Authors: Hedtke Lorraine
Published: April 2014

A narrative approach allows psychosocial teams to stand alongside children who have cancer, or life‐threatening illnesses, and their families at critical times and to create stories of agency. Rather than dwelling on stories of loss and despair that potentially enfeeble families, a narrative approach builds on stories of strength that engender hope by asking questions that separate the person from the problem. Developing such stories supports people in taking action against the effects of cancer. It also facilitates the formation of a legacy that can sustain family members, even after the death of a child. This legacy serves as the foundation for remembering the dead, folding their stories into the lives of the living, and constructing lines of relational connection that can transcend physical death. Not only do families benefit from this approach, but the psychosocial team that provides professional and medical services can be uplifted through witnessing practices of strength and love in the face of hardship.
The Gift of Giving: Empowering Vulnerable Children, Families and Communities in Rural Uganda
Authors: Wakhungu Caleb
Published: April 2014

Caleb Wakhungu and the Mt Elgon Self‐Help Community Project use narrative ideas and practices to spark and sustain local economic ‘development’ projects in rural Uganda. Their innovative work links community work, therapy and development. This short paper describes the significance of moving away from a children's rights model (which had been imported from the West) to a model of empowering children and families in ways that are congruent with local cultural practices and understandings.
Weaving Net‐works of Hope with Families, Practitioners and Communities: Inspirations from Systemic and Narrative Approaches
Authors: Fredman Glenda
Published: April 2014

Over the last decade, inspired by systemic family therapy and narrative approaches, Glenda Fredman's team in the UK has found ways to bring families, practitioners and communities together to respond to medical, mental health and social care crises. This work has taken place with children, adolescents, older people and people affected by intellectual disability and their families. This paper shares an inspiring story of this work and describes ways of ‘conducting’ and ‘weaving’ networks of hope.
Narrative Family Therapy and Group Work for Families Living with Acquired Brain Injury
Authors: Butera‐Prinzi Franca , Charles Nella , Story Karen
Published: April 2014

Acquired brain injury profoundly challenges the identity of the affected person and family relationships. Narrative practices offer valuable therapeutic tools to assist families to face the enormous task of adjusting to an acquired disability. The integration of family therapy and group work provides multiple avenues for families to have their experiences validated and to support reconnection with strengths, values and goals. It is from this more empowered position that families can find ways to live their lives to the fullest, in spite of the difficulties.
Synthesis and characterization of inherently flame‐retardant and anti‐dripping thermoplastic poly(imides‐urethane)s
Authors: Tang Qiheng , Song Yun , He Jiyu , Yang Rongjie
Published: April 2014

A series of thermoplastic poly(imide‐urethane)s (TPIUs), based on 4,4′‐diphenylmethane diisocyanate (MDI) and pyromellitic anhydride (PMDA) as hard segments and poly(tetrahydrofuran) (PTMG) as soft segments, has been prepared by a two‐step polymerization process. The objective of this study is to prepare a type of intrinsically flame‐retardant polyurethane by incorporating PMDA as a flame retardant in the main chains. The thermal behavior and flame retardancies of the TPIUs have been characterized by thermal gravimetric (TG) analysis and limiting oxygen index (LOI), UL‐94 vertical burning, cone calorimeter tests. The results indicate that the TPIUs display outstanding performance. The temperature at 5% mass loss (T5%) and LOI value increase with the hard‐segment contents, while the total heat released (THR) and peak heat release rate (p‐HRR) show the opposite trend. Furthermore, the T5% of TPIU211 (molar ratio: MDI : PTMG : PMDA = 2 : 1 : 1) is 33.2°C higher than that of the conventional thermoplastic polyurethane TPU211 (molar ratio: MDI : PTMG : 1,4‐butanediol = 2 : 1 : 1), and the THR and p‐HRR of TPIU211 are 14.62% and 64.02% lower than the respective parameters of TPU211. In addition, UL‐94 vertical burning tests show that the TPIUs exhibit excellent antidripping effects. The ultimate tensile strengths of the TPIUs reached 23.1−37.6 MPa with increasing hard segment contents, which meets the requirement of mechanical properties with regard to practical use. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40801.
High dielectric constant polyimide derived from 5,5′‐bis[(4‐amino) phenoxy]‐2,2′‐bipyrimidine
Authors: Peng Xinwen , Wu Qiong , Jiang Shaohua , Hanif Muddasir , Chen Shuiliang , Hou Haoqing
Published: April 2014

Polyimides (PIs) are highly desirable materials due to their excellent physical, chemical properties, and widespread applications. In this article, a new PI containing bipyrimidine units was prepared from a newly synthesized 5,5′‐bis[(4‐amino) phenoxy]‐2,2′‐bipyrimidine and 3‚3′‚4‚4′‐biphenyltetracarboxylic dianhydride via a two‐step method. The as‐synthesized PI not only showed high thermal stability and excellent mechanical properties, but also possessed high dielectric constant (7.1, 100 Hz) and low dielectric loss (below 0.04) in a wide frequency range from 100 Hz to 105 Hz. The obtained PI promises potential applications in electronic products. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40828.
Nonisothermal crystallization kinetics of poly(butylene terephthalate)/multiwalled carbon nanotubes nanocomposites prepared by in situ polymerization
Authors: Fang Hui , Wu Fangjuan
Published: April 2014

Poly(butylene terephthalate)/multiwalled carbon nanotubes (PBT/MWNT) nanocomposites were prepared by in situ ring‐opening polymerization of cyclic butylene terephthalate oligomers (CBT). The nonisothermal crystallization behavior of the neat PBT and the PBT/MWNT nanocomposites was analyzed quantitatively. The results reveal that the combined Avrami/Ozawa equation exhibits great advantages in describing the nonisothermal crystallization of PBT and its nanocomposites. The presence of MWNTs has the nucleation effect promoting crystallization rate for the nanocomposites, and the maximum one is observed in the nanocomposite having 0.75 wt % MWNT content. On the other hand, the addition of MWNTs has the impeding effect reducing the chain mobility and retarding crystallization, which is confirmed by the crystallization activation energies. However, the nucleation effect of MWNTs plays the dominant role in the crystallization of PBT/MWNT nanocomposites, in other words, the incorporation of MWNTs is increasing the crystallization rate of the nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40849.
Incidental catch of marine turtles by Spanish bottom trawlers in the western Mediterranean
Authors: Domènech Francesc , Álvarez de Quevedo Irene , Merchán Manuel , Revuelta Ohiana , Vélez‐Rubio Gabriela , Bitón Sebastián , Cardona Luis , Tomás Jesús
Published: April 2014

A questionnaire‐based survey of fishermen was conducted in the Valencia region (eastern Spain) to assess the levels of marine turtle bycatch. Interviews covered 41.3% of the bottom trawling fleet in the region and included 111 fishermen (one per boat). Results were combined with those from previous studies conducted in neighbouring regions using the same methodology to assess the global impact of bottom trawling on the western Mediterranean stock of the loggerhead turtle (Caretta caretta).

Estimated turtle catch per unit effort (CPUE) is 0.09 turtles per vessel per month, according to the information reported by fishermen. As a consequence, the whole fleet of bottom trawlers operating off the Valencia region was involved annually in 238 turtle bycatch events (95%, CI: 173–304).

Ivlev's electivity index revealed that bottom trawling bycatch was higher than expected according to fishing effort in the northern part of the study area, where the continental shelf widens.

The fishermen's perception was that the local stock of loggerhead turtles is declining, and that drifting longlines and bottom trawling are, at least in part, responsible for this trend.

According to previous studies as well as the current results, bottom trawlers operating off mainland Spain capture mainly loggerhead turtles from the rookeries in the eastern Mediterranean, with only a low percentage of turtles of Atlantic origin.

Loggerhead turtle bycatch by bottom trawling deserves more attention in the Valencia region, particularly in its northern part. Conservation measures in the area are discussed.

Copyright © 2014 John Wiley & Sons, Ltd.