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Carboxylic Acid Production

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ISBN: 9783038425526 9783038425533 Year: Pages: 174 DOI: 10.3390/books978-3-03842-553-3 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biology
Added to DOAB on : 2018-01-04 15:30:04
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Carboxylic acids are truly central compounds in cellular metabolism. Carbon dioxide is captured from the atmosphere through formation of carboxylic groups and is also released, in part, by decarboxylation reactions. The reactivity of the carboxylic group with amino- or hydroxyl-groups enables the formation of peptide and ester bonds. The functionality of the carboxylic group is also of huge importance in our industrial world for a wide range of applications. The loosely bound hydrogen provides weak acid functionality, much desired for food industry applications in preservatives and flavour compounds. Citric acid is one of our oldest industrial fermentation products. The presence of two carboxylic groups, or a combination of one carboxylic group and another functional group, make the compounds interesting building blocks for polymer production. A number of carboxylic acids, including, e.g., lactic, succinic, 3-hydroxypropionic and itaconic acids, have been identified and recognized as suitable platform chemicals for a foreseen growing carbohydrate based economy. Economic margins are, however, tight when competing with petroleum based production, and production strains, fermentation technology and—not least—downstream processing, all need to be improved to enable viable commercial production.This Special issue will cover current developments within this exciting field. Topics will include: Fermentation physiology of natural carboxylic acid producers; screening and isolation of novel producers; metabolic engineering for improving intrinsic carboxylic acid production; metabolic engineering for expanding product range to non-endogenous carboxylic acids; production from lignocellulosic derived sugars or by-product streams; downstream processing for recovery of carboxylic acids; bioprocess design—including continuous processes and integration.All production organisms—fungi, yeasts, bacteria—are welcome.

Deformation Behavior of Thin Metallic Wires under Tensile and Torsional Loadings

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Book Series: Schriftenreihe des Instituts für Angewandte Materialien, Karlsruher Institut für Technologie ISSN: 21929963 ISBN: 9783731500490 Year: Volume: 26 Pages: V, 158 p. DOI: 10.5445/KSP/1000035547 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:02
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Size effects are widely observed in the mechanics of materials at the micron scale. However, the underlying deformation mechanisms remain ambiguous, particularly in the presence of strain gradients. In this work, combined microstructural investigations and mechanical tests (tension and torsion) were conducted on polycrystalline gold micro wires to determine the influences of specimen size, grain size, strain rate and loading type on the deformation behavior of the wires.

Advances in Polyhydroxyalkanoate (PHA) Production

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ISBN: 9783038426370 9783038426363 Year: Pages: X, 245 DOI: 10.3390/books978-3-03842-636-3 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biotechnology
Added to DOAB on : 2017-12-22 11:01:59
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Currently, we are witnessing highly dynamic research efforts related to the exciting field of novel biodegradable plastic-like materials. These activities originate from a growing public awareness of prevailing ecological problems associated to, e.g., rising piles of plastic waste, increasing greenhouse gas emissions, and ongoing depletion of such fossil resources usually used for the synthesis of “full carbon backbone” plastics. Polyhydroxyalkanoate (PHA) biopolyesters, a family of versatile plastic-like materials produced by living microbes, are a future-oriented alternative to traditional plastics. If accomplished in an optimized way, production and the entire lifecycle of PHA are embedded into nature´s closed carbon cycle, which is underlined by PHA´s main benefits of being “biobased”, “biosynthesized”, “biocompatible”, and “biodegradable”.Sustainable and economically feasible PHA synthesis, especially on an industrially relevant scale, requires all production steps to be understood and improved. Among other aspects, this calls for new powerful production strains to be screened; knowledge about the proteome and genome of PHA accumulating organisms to be consolidated; the kinetics of the bioprocesses to be thoroughly understood; abundantly available inexpensive raw materials to be tested; the monomer composition of PHA to be adapted; (bio)chemical engineering to be optimized; and novel PHA recovery strategies to be developed in order to reduce energy and chemical inventory.The present book provides a comprehensive compilation of articles addressing all these different aspects; the individual chapters were composed by globally recognized front running experts from special niches of PHA research. We are convinced that this book will be of major benefit to the growing scientific community active in biopolymer research.

Psychosocial Job Dimensions and Distress/Well-Being: Issues and Challenges in Occupational Health Psychology

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889454082 Year: Pages: 261 DOI: 10.3389/978-2-88945-408-2 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Psychology
Added to DOAB on : 2018-11-16 17:17:57
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Over the last three decades a large body of research has showed that psychosocial job dimensions such as time pressure, decision authority and social support, could have significant implications for psychological distress and well-being. Theoretical models, such as the job demand-control-social support model (JDCS model), the effort-reward imbalance model (ERI model), the job demands-resources model (JDR model) and the vitamin model suggest that distress and positive dimensions at work (well being and motivation) can be considered as two sides of the same coin. If the job is designed to provide the right mix of psychosocial job dimensions (e.g., optimal time pressure, decision authority and social support), work can boost job engagement and well-being as well as productive behaviors at work. When the job is not designed in an optimal way (e.g., too much time pressure and too little decision authority) work can trigger stress reactions and burnout. Although some insight has been gained on how job dimensions could predict distress and well-being, and also into the dimensions that might moderate and mediate these associations; research still faces several challenges. Firstly, most of this research has been cross-sectional in nature, thus making it difficult to conclude on the long-term effects of psychosocial job dimensions. Another challenge concerns how the contextual dimensions can be incorporated into micro-levels models on employee stress and well-being. Nowadays, work is carried out in the context of a wider environment that includes organizational variables. So far the role of the organizational variables in the theoretical frameworks for explaining the relationships between psychosocial job dimensions, employee distress and well-being, has often been underplayed. The main aim of this research topic is to bring together international research from different theoretical and methodological perspectives in order to advance knowledge and practice in the field of work stress.

Hybride Werkstoffsysteme: Systematische Betrachtung und Bewertung der physikalischen Wirkmechanismen

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Book Series: Karlsruher Schriftenreihe Fahrzeugsystemtechnik / Institut für Fahrzeugsystemtechnik ISSN: 18696058 ISBN: 9783731509011 Year: Volume: 72 Pages: XIV, 191 p. DOI: 10.5445/KSP/1000091217 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:00
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Hybrid material systems result from the specific combination of different materials. For optimized design of hybrid material systems for structural components, a profound fundamental understanding regarding the interaction of the different materials is of great importance. This work systematically investigates adhesively bonded hybrid material systems and assesses the underlying mechanisms with experimental and numerical methods.

Sports Materials

Authors: --- --- ---
ISBN: 9783039281626 9783039281633 Year: Pages: 166 DOI: 10.3390/books978-3-03928-163-3 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: General and Civil Engineering --- Technology (General)
Added to DOAB on : 2020-01-30 16:39:46
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Advances in materials are crucial to the development of sports equipment, from tennis rackets to skis to running shoes. Materials-driven improvements in equipment have helped athletes perform better, while enhancing safety and making sport more accessible and enjoyable. This book brings together a collection of 10 papers on the topic of sports materials, as published in a Special Issue of Applied Sciences. The papers within this book cover a range of sports, including golf, tennis, table tennis and baseball. State-of-the-art engineering techniques, such as finite element modelling, impact testing and full-field strain measurement, are applied to help further our understanding of sports equipment mechanics and the role of materials, with a view to improving performance, enhancing safety and facilitating informed regulatory decision making. The book also includes papers that describe emerging and novel materials, including auxetic materials with their negative Poisson’s ratio (fattening when stretched) and knits made of bamboo charcoal. This collection of papers should serve as a useful resource for sports engineers working in both academia and industry, as well as engineering students who are interested in sports equipment and materials.

Ultrasound Elastography

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ISBN: 9783038979104 9783038979111 Year: Pages: 144 DOI: 10.3390/books978-3-03897-911-1 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General) --- Therapeutics
Added to DOAB on : 2019-08-28 11:21:27
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The comparison between methods, evaluation of portal hypertension and many other questions are still open issues in liver elastography. New elastographic applications are under evaluation and close to being used in clinical practice. Strain imaging has been incorporated into many disciplines and EFSUMB guidelines are under preparation. More research is necessary for improved evidence for clinical applications in daily practice. The Special Issue published papers on recent advances in development and application of Ultrasound Elastography.

Geomechanics for Energy and a Sustainable Environment

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ISBN: 9783039281503 9783039281510 Year: Pages: 102 DOI: 10.3390/books978-3-03928-151-0 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: General and Civil Engineering --- Technology (General)
Added to DOAB on : 2020-01-30 16:39:46
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This book describes recent advances in geomechanics for energy and the sustainable environment. Four research articles, related to high-level radioactive nuclear waste disposal stability, geological effect and wellbore stability considerations for methane gas hydrate production, and artificial soil freezing, are presented in this book. In addition, a comprehensive state-of-the-art review verifies the strong correlation between global climate change and the occurrence of geotechnical engineering hazards. The review also summarizes recent attempts to reduce CO2 emissions from civil and geotechnical engineering practices. Readers will gain ideas as to how we can deal with conventional and renewable energy sources and environment-related geotechnical engineering issues.

Enteric Viruses in Aquatic Environments

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ISBN: 9783039285686 / 9783039285693 Year: Pages: 84 DOI: 10.3390/books978-3-03928-569-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General)
Added to DOAB on : 2020-06-09 16:38:57
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This Special Issue contains one review and five original articles, all of which address cutting-edge research in the field of water and environmental virology. The review article by Gerba and Betancourt summarizes the current status and future needs for the development of virus detection methods in water reuse systems, especially focusing on methods to assess the infectivity of enteric viruses. Original papers cover a variety of research topics, such as an environmental monitoring survey of group A rotaviruses in sewage and oysters in Japan, the occurrence and genetic diversity of noroviruses and rotaviruses in a wastewater reclamation system in China, the detection of viruses and their indicators in tanker water and its sources in Nepal, integrated culture next-generation sequencing to identify the diversity of F-specific RNA coliphages in wastewater, and the development of a portable collection and detection method for viruses from ambient air and its application to a wastewater treatment plant.

Advances in Digital Image Correlation (DIC)

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ISBN: 9783039285143 / 9783039285150 Year: Pages: 252 DOI: 10.3390/books978-3-03928-515-0 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2020-06-09 16:38:57
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Digital image correlation (DIC) has become the most popular full field measurement technique in experimental mechanics. It is a versatile and inexpensive measurement method that provides a large amount of experimental data. Because DIC takes advantage of a huge variety of image modalities, the technique allows covering a wide range of space and time scales. Stereo extends the scope of DIC to non-planar cases, which are more representative of industrial use cases. With the development of tomography, digital volume correlation now provides access to volumetric data, enabling the study of the inner behavior of materials and structures.However, the use of DIC data to quantitatively validate models or accurately identify a set of constitutive parameters remains challenging. One of the reasons lies in the compromises between measurement resolution and spatial resolution. Second, the question of the boundary conditions is still open. Another reason is that the measured displacements are not directly comparable with usual simulations. Finally, the use of full field data leads to new computational challenges.

Keywords

super pressure balloon --- stress concentration --- strain --- non-contact measurement --- digital image correlation --- large deformation --- digital image correlation --- multi-perspective --- single camera --- cross dichroic prism --- earthquake rupture --- fault geometry --- spatiotemporal evolution --- strain gage --- spatial sampling rate --- rupture speed --- slip velocity --- high-speed camera --- experimental-numerical method --- digital image correlation --- finite element method --- static analysis --- arch structures --- fracture process zone --- digital image correlation technique --- acoustic emission technique --- stress intensity factor --- 3D deformation --- digital volume correlation --- optical coherence elastography --- virtual fields method --- layered material --- interior 3D deformation --- digital volumetric speckle photography --- X-ray microtomography --- digital volume correlation --- red sandstone --- woven composite beam --- digital image correlation --- dynamic interfacial rupture --- traction continuity across interfaces --- non-contact video gauge --- measurement --- stress-strain relationship --- uniaxial tensile test --- elevated temperature --- DIC --- initial condition --- image registration --- strain measurement --- copper plate --- underwater impulsive loading --- non-liner dynamic deformation --- 3D digital image correlation --- image correlation --- gradient correlation functions --- laser speckles --- image cross-correlation --- monitoring --- geosciences --- automated systems --- machine learning --- image classification --- image shadowing --- characterization of composite materials --- interlaminar tensile strength --- digital image correlation --- inverse method --- finite element model updating --- Digital image correlation (DIC) --- composite structures --- structural testing --- experimental mechanics --- composite materials --- automated composite manufacturing --- composite inspection --- automated fiber placement (AFP) --- DIC --- traceable calibration --- accuracy --- error --- n/a

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