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Entwicklung und Optimierung eines biotechnologischen Prozesses zur Herstellung mikrobieller Rhamnolipide auf Basis nachwachsender Rohstoffe

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ISBN: 9783866442771 Year: Pages: 156 p. DOI: 10.5445/KSP/1000009236 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Chemical Engineering
Added to DOAB on : 2019-07-30 20:02:02
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Im Fokus dieser Arbeit steht die Entwicklung und Optimierung eines biotechnologischen Prozesses zur Herstellung von Rhamnolipiden auf Basis von nachwachsenden Rohstoffen. Ein Schwerpunkt lag hierbei auf der Entwicklung und Evaluierung einer Standardprozessführung, sowie eines auf einem Parallelbioreaktor basierenden, effizienten Screening-Systems. Ein Produk­tions­stammvergleich wurde durchgeführt. Zur Produktanalyse sollte FTIR-Spektroskopie als alternative Analysemethode eingesetzt werden.

Current challenges in photosynthesis: From natural to artificial

Authors: --- --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889192861 Year: Pages: 102 DOI: 10.3389/978-2-88919-286-1 Language: English
Publisher: Frontiers Media SA
Subject: Physiology --- Botany --- Science (General)
Added to DOAB on : 2015-12-10 11:59:07
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Jules Verne (1828-1905), author of Around the World in Eighty Days (1873) and Journey to the Center of the Earth (1864), wrote in 1875:"I believe that water will one day be used as a fuel, because the hydrogen and oxygen which constitute it, used separately or together, will furnish an inexhaustible source of heat and light. I therefore believe that, when coal (oil) deposits are oxidised, we will heat ourselves by means of water. Water is the fuel of the future". Solar energy is the only renewable energy source that has sufficient capacity for the global energy need; it is the only one that can address the issues of energy crisis and global climate change. A vast amount of solar energy is harvested and stored via photosynthesis in plants, algae, and cyanobacteria since over 3 billion years. Today, it is estimated that photosynthesis produces more than 100 billion tons of dry biomass annually, which would be equivalent to a hundred times the weight of the total human population on our planet at the present time, and equal to a global energy storage rate of about 100 TW. The solar power is the most abundant source of renewable energy, and oxygenic photosynthesis uses this energy to power the planet using the amazing reaction of water splitting. During water splitting, driven ultimately by sunlight, oxygen is released into the atmosphere, and this, along with food production by photosynthesis, supports life on our earth. The other product of water oxidation is “hydrogen” (proton and electron). This ‘hydrogen’ is not normally released into the atmosphere as hydrogen gas but combined with carbon dioxide to make high energy containing organic molecules. When we burn fuels we combine these organic molecules with oxygen. The design of new solar energy systems must adhere to the same principle as that of natural photosynthesis. For us to manipulate it to our benefit, it is imperative that we completely understand the basic processes of natural photosynthesis, and chemical conversion, such as light harvesting, excitation energy transfer, electron transfer, ion transport, and carbon fixation. Equally important, we must exploit application of this knowledge to the development of fully synthetic and/or hybrid devices. Understanding of photosynthetic reactions is not only a satisfying intellectual pursuit, but it is important for improving agricultural yields and for developing new solar technologies. Today, we have considerable knowledge of the working of photosynthesis and its photosystems, including the water oxidation reaction. Recent advances towards the understanding of the structure and the mechanism of the natural photosynthetic systems are being made at the molecular level. To mimic natural photosynthesis, inorganic chemists, organic chemists, electrochemists, material scientists, biochemists, biophysicists, and plant biologists must work together and only then significant progress in harnessing energy via “artificial photosynthesis” will be possible. This Research Topic provides recent advances of our understanding of photosynthesis, gives to our readers recent information on photosynthesis research, and summarizes the characteristics of the natural system from the standpoint of what we could learn from it to produce an efficient artificial system, i.e., from the natural to the artificial. This topic is intended to include exciting breakthroughs, possible limitations, and open questions in the frontiers in photosynthesis research.

Siloxane-Based Polymers

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ISBN: 9783038971252 / 9783038971269 Year: Pages: 188 DOI: 10.3390/books978-3-03897-126-9 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Chemical Engineering
Added to DOAB on : 2019-08-28 11:21:27
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This book, a collection of 12 original contributions and 4 reviews, provides a selection of the most recent advances in the preparation, characterization, and applications of polymeric nanocomposites comprising nanoparticles. The concept of nanoparticle-reinforced polymers came about three decades ago, following the outstanding discovery of fullerenes and carbon nanotubes. One of the main ideas behind this approach is to improve the matrix mechanical performance. The nanoparticles exhibit higher specific surface area, surface energy, and density compared to microparticles and, hence, lower nanofiller concentrations are needed to attain properties comparable to, or even better than, those obtained by conventional microfiller loadings, which facilitates processing and minimizes the increase in composite weight. The addition of nanoparticles into different polymer matrices opens up an important research area in the field of composite materials. Moreover, many different types of inorganic nanoparticles, such as quantum dots, metal oxides, and ceramic and metallic nanoparticles, have been incorporated into polymers for their application in a wide range of fields, ranging from medicine to photovoltaics, packaging, and structural applications.

Keywords

fabrication --- multielectrode array (MEA) --- PDMS --- PDMS etching --- plateau-shaped electrode --- recessed electrode --- spinal cord signal recording --- underexposure --- organosilane --- quartz microcrystal --- encapsulant --- refractive index --- thermal conductivity --- poly(dimethylsiloxanes) --- surface modification --- nanosilica --- diethyl carbonate --- carbon content --- morphology --- coatings --- fillers --- hybrid hydrogel --- MAPOSS --- mechanical properties --- swelling --- drug release --- dental resin --- methacryl POSS --- shrinkage --- hardness --- scratch resistance --- ceramizable silicone rubber --- borate --- halloysite --- composite --- ceramizable mechanism --- polysiloxanes --- mortar --- basalt fibre --- roughness --- surface free energy --- poly(ethylene glycol) (PEG) --- hydrophilic --- non-releasable --- polydimethylsiloxane --- coatings --- cross-linking --- surface --- amphiphilic --- anti-bioadhesion --- hyperbranched poly(methylhydrosiloxanes) --- hydrolytic polycondensation --- 29Si-NMR --- topology of polysiloxane chains --- polyhedral oligomeric silsesquioxanes --- high molecular weight --- nanoparticles --- PDMS --- sugar templating process --- 3D porous network --- thermal stability --- TG-FTIR --- X-ray (Micro-CT) microtomography --- sol-gel --- hybrids --- chlorogenic acid --- bioactivity --- FTIR --- TG --- polysiloxanes --- theranostics --- drug delivery --- nanomedicine --- PDMS --- silicon --- ultraviolet (UV) curable coatings --- low surface energy materials --- fluorinated siloxane resin

Synthesis and Applications of Biopolymer Composites

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ISBN: 9783039211326 / 9783039211333 Year: Pages: 312 DOI: 10.3390/books978-3-03921-133-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Chemical Engineering
Added to DOAB on : 2019-08-28 11:21:27
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This book, as a collection of 17 research articles, provides a selection of the most recent advances in the synthesis, characterization, and applications of environmentally friendly and biodegradable biopolymer composites and nanocomposites. Recently, the demand has been growing for a clean and pollution-free environment and an evident target regarding the minimization of fossil fuel usage. Therefore, much attention has been focused on research to replace petroleum-based commodity plastics by biodegradable materials arising from biological and renewable resources. Biopolymers—polymers produced from natural sources either chemically from a biological material or biosynthesized by living organisms—are suitable alternatives for addressing these issues due to their outstanding properties, including good barrier performance, biodegradation ability, and low weight. However, they generally possess poor mechanical properties, a short fatigue life, low chemical resistance, poor long-term durability, and limited processing capability. In order to overcome these deficiencies, biopolymers can be reinforced with fillers or nanofillers (with at least one of their dimensions in the nanometer range). Bionanocomposites are advantageous for a wide range of applications, such as in medicine, pharmaceutics, cosmetics, food packaging, agriculture, forestry, electronics, transport, construction, and many more.

Keywords

nanocellulose --- protease sensor --- human neutrophil elastase --- peptide-cellulose conformation --- aerogel --- glycol chitosan --- ?-tocopherol succinate --- amphiphilic polymer --- micelles --- paclitaxel --- chitosan --- PVA --- nanofibers --- electrospinning --- nanocellulose --- carbon nanotubes --- nanocomposite --- conductivity --- surfactant --- Poly(propylene carbonate) --- thermoplastic polyurethane --- compatibility --- toughness --- biopolyester --- compatibilizer --- cellulose --- elastomer --- toughening --- biodisintegration --- heat deflection temperature --- biopolymers composites --- MgO whiskers --- PLLA --- in vitro degradation --- natural rubber --- plasticized starch --- polyfunctional monomers --- physical and mechanical properties --- cross-link density --- water uptake --- chitosan --- deoxycholic acid --- folic acid --- amphiphilic polymer --- micelles --- paclitaxel --- silk fibroin --- glass transition --- DMA --- FTIR --- stress-strain --- active packaging materials --- alginate films --- antimicrobial agents --- antioxidant activity --- biodegradable films --- essential oils --- polycarbonate --- thermal decomposition kinetics --- TG/FTIR --- Py-GC/MS --- wheat gluten --- potato protein --- chemical pre-treatment --- structural profile --- tensile properties --- biocomposites --- natural fibers --- poly(3-hydroxybutyrate-3-hydroxyvalerate) --- biodegradation --- impact properties --- chitin nanofibrils --- poly(lactic acid) --- nanocomposites --- bio-based polymers --- natural fibers --- biomass --- biocomposites --- fiber/matrix adhesion --- bio-composites --- mechanical properties --- poly(lactic acid) --- cellulose fibers --- n/a

Multiscale and Innovative Kinetic Approaches in Heterogeneous Catalysis

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ISBN: 9783039211791 / 9783039211807 Year: Pages: 214 DOI: 10.3390/books978-3-03921-180-7 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-08-28 11:21:27
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Kinetics and reactor modeling for heterogeneous catalytic reactions are prominent tools for investigating and understanding catalyst functionalities at nanoscale and the related rates of complex reaction networks. This book illustrates some examples related to the transformation of simple to more complex feedstocks, including different types of reactor designs, i.e., steady-state, transient plug flow reactors, and TAP reactors for which there is sometimes a strong gap in the operating conditions from ultra-high-vacuum to high-pressure conditions. In conjunction, new methodologies have emerged, giving rise to more robust microkinetics models. As exemplified, they include the kinetics and the dynamics of the reactors and span a large range of length and time scales. The objective of this Special Issue is to provide contributions that can illustrate recent advances and novel methodologies for elucidating the kinetics of heterogeneous reactions and the necessary multiscale approach for optimizing the reactor design. This book is dedicated to postgraduate and scientific researchers, and experts in heterogeneous catalysis. It may also serve as a source of original information for the elaboration of lessons on catalysis for Master students.

Titanium Dioxide Photocatalysis

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ISBN: 9783038976943 / 9783038976950 Year: Pages: 208 DOI: 10.3390/books978-3-03897-695-0 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General)
Added to DOAB on : 2019-06-26 08:44:06
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Although the seminal work of Fujishima et al. dates back to 1971, TiO2 still remains the most diffused and studied semiconductor, employed in photo-oxidation processes for cleantech (i.e., polluted water and air treatment), in solar fuel production (mainly hydrogen production by water photo splitting), and in Carbon Capture and Utilization (CCU) processes by CO2 photoreduction. The eleven articles, among them three reviews, in this book cover recent results and research trends of various aspects of titanium dioxide photocatalysis, with the chief aim of improving the final efficiency of TiO2-based materials. Strategies include doping, metal co-catalyst deposition, and the realization of composites with plasmonic materials, other semiconductors, and graphene. Photocatalysts with high efficiency and selectivity can be also obtained by controlling the precise crystal shape (and homogeneous size) and the organization in superstructures from ultrathin films to hierarchical nanostructures. Finally, the theoretical modeling of TiO2 nanoparticles is discussed and highlighted. The range of topics addressed in this book will stimulate the reader’s interest as well as provide a valuable source of information for researchers in academia and industry.

Advances in Chitin/Chitosan Characterization and Applications

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ISBN: 9783038978022 9783038978039 Year: Pages: 414 DOI: 10.3390/books978-3-03897-803-9 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology --- Biochemistry
Added to DOAB on : 2019-04-25 16:37:17
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Functional advanced biopolymers have received far less attention than renewable biomass (cellulose, rubber, etc.) used for energy production. Among the most advanced biopolymers known is chitosan. The term chitosan refers to a family of polysaccharides obtained by partial de-N-acetylation from chitin, one of the most abundant renewable resources in the biosphere. Chitosan has been firmly established as having unique material properties as well as biological activities. Either in its native form or as a chemical derivative, chitosan is amenable to being processed—typically under mild conditions—into soft materials such as hydrogels, colloidal nanoparticles, or nanofibers. Given its multiple biological properties, including biodegradability, antimicrobial effects, gene transfectability, and metal adsorption—to name but a few—chitosan is regarded as a widely versatile building block in various sectors (e.g., agriculture, food, cosmetics, pharmacy) and for various applications (medical devices, metal adsorption, catalysis, etc.). This Special Issue presents an updated account addressing some of the major applications, including also chemical and enzymatic modifications of oligos and polymers. A better understanding of the properties that underpin the use of chitin and chitosan in different fields is key for boosting their more extensive industrial utilization, as well as to aid regulatory agencies in establishing specifications, guidelines, and standards for the different types of products and applications.

Keywords

aerogels --- chitosan --- ionic liquids --- ionogels --- zinc–chitosan complexes --- characterization --- bio-sorbent --- phosphate --- adsorption --- mechanism --- thermodynamic --- chitosan --- hydrogel --- phase transition --- gelation mechanism --- chitosan --- defense responses --- fruits --- nanoparticles --- plant growth --- pesticides --- Boron --- chitosan --- iron(III) hydroxide --- neodymium --- sorption --- chitin --- chitosan --- chitosan derivative --- chitin derivative --- oral care --- skin care --- hear care --- marine resources --- over-the counter-drug --- polymer carrier --- chitin --- chitosan --- nanostructured biomaterial --- polymer --- self-masking nanosphere lithography --- cicada --- chitosan --- self-assembled --- polyelectrolyte complex --- nanoparticle --- drug delivery --- Citrobacter --- biosynthesis --- bioflocculant --- chitosan --- metabolic pathway --- PEO/chitosan blend --- swelling --- mechanical properties --- wet and dried states --- chitosan --- biological activity --- medical applications --- chitosan --- PCL --- strontium --- scaffolds --- craniofacial engineering --- chitin --- chitosan --- derivatization --- controlled functionalization --- click chemistry --- graft copolymer --- cyclodextrin --- dendrimer --- ionic liquids --- chitin deacetylases --- chitosan --- chitooligosaccharides --- carbohydrate esterases --- structure --- substrate specificity --- deacetylation pattern --- binary --- chitosan --- desorption --- iron --- lead --- mercury --- salt effects --- single --- sorption competition --- chitosan supported copper --- heterogeneous catalyst --- organosilicon compound --- easily recyclable --- chitosan --- papermaking --- wet-end --- coating --- wastewater --- ionic cross-linking --- eco-friendly formulations --- thermal transition sol-gel --- drug delivery systems --- MTDSC --- DSC --- gene delivery --- non-viral vectors --- chitosan structure --- pDNA --- siRNA --- TEOS --- methylene blue --- chitosan --- modelling --- cross-linking --- interpenetrating --- XRD --- FTIR

Special Issue Dedicated to Late Professor Takuo Okuda. Tannins and Related Polyphenols Revisited: Chemistry, Biochemistry and Biological Activities

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ISBN: 9783038978343 / 9783038978350 Year: Pages: 316 DOI: 10.3390/books978-3-03897-835-0 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2019-06-26 10:09:00
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Antioxidative polyphenols represented by tannins and flavonoids are rich in numerous food sources and traditional natural medicines and currently attracting increased attention in health care and food industries because of their multiple biological activities that are favorable to human health. Commemorating the outstanding achievements on tannins by Dr. Takuo Okuda on the occasion of his passing away in December 2016, his colleagues, friends, and worldwide experts of polyphenol research have contributed 18 papers on their recent study to the Special Issue of Molecules. This book is its reprinted form. This covers reviews of structural features, historical usages, and biological activities of unique class of ellagitannins and condensed tannins, and original articles on the most up-to-date findings on the anticancer effect of green tea catechins, the antivirus effect of tannins comparing with the clinically used drugs, the analytical method of ellagitannins using quantitative NMR, the chemical structures of Hydrangea-blue complex (pigment) and condensed tannins in Ephedra sinica and purple prairie clover, and the relationship of condensed tannins in legumes and grape-marc with methane production in the in vitro ruminant system, and others. This book will be useful to natural product chemists and also to researchers in pharmaceutical and/or food industry.

Keywords

Dittrichia viscosa --- antifungal activities --- Candida spp. --- Malassezia spp. --- Microsporum canis --- Aspergillus fumigates --- Ephedra sinica --- proanthocyanidin --- oligomer --- thiolysis --- phloroglucinolysis --- TDDFT --- ECD --- neuraminidase --- inhibition --- tannins --- oseltamivir carboxylate --- zanamivir --- crystal structure --- molecular interactions --- oenothein B --- ellagitannin --- macrocyclic oligomer --- Onagraceae --- Myrtaceae --- Lythraceae --- antioxidants --- antitumor effect --- immunomodulatory effect --- anti-inflammation --- tannin composition --- purple prairie clover --- conservation method --- protein precipitation --- Escherichia coli --- Cynanchum wilfordii --- phenolic glycoside --- 2-O-?-laminaribiosyl-4-hydroxyacetophenone --- cynandione A --- thin layer chromatography --- Cynanchum auriculatum --- Acacia mearnsii bark --- wattle tannin --- proanthocyanidins --- biological activities --- tannins --- vegetable tanning --- European historic leathers --- colorimetric tests --- spectroscopy --- UV-Vis --- FTIR --- triple-negative breast cancer --- fatty acid synthase --- FASN inhibition --- polyphenolic FASN inhibitors --- (?)-epigallocatechin 3-gallate --- synthetic analogues --- apoptosis --- anticancer activity --- 1H-NMR --- quantitative NMR --- ellagitannin --- Geranium thunbergii --- geraniin --- Aluminum ion --- blue color development --- 5-O-caffeoylquinic acid --- 3-O-glucosyldelphinidin --- Hydrangea macrophylla --- ESI-mass --- metal complex --- Coreopsis lanceolata L. --- chalcone --- flavanone --- flavonol --- aurone --- Horner–Wadsworth–Emmons reaction --- condensed tannin --- bioactivity --- methanogenesis --- grape marc --- fatty acids --- in vitro batch fermentation --- neuroprotection --- PC12 --- NGF --- differentiation --- amyloid-? peptide --- taxanes --- hormesis --- polyphenol --- bamboo leaf extract --- overlay method --- ellagitannin --- structure --- revision --- (?)-epigallocatechin gallate --- immune checkpoint --- interferon-? --- epidermal growth factor --- lung tumor --- proanthocyanidins --- condensed tannins --- thiolysis --- NMR spectroscopy --- ultrahigh-resolution negative mode MALDI-TOF mass spectrometry --- antioxidant --- ORAC assay --- Acacia --- forage legume --- Trapa taiwanensis Nakai --- hydrolysable tannin --- stability --- gallotannin --- ellagitannin

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