für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This study involved a survey on the use of dithiocarbamates in agriculture practices in Bukavu Region and the determination of their residues in vegetables (tomatoes and cabbages) from five main sites supplying Bukavu town with vegetables. Analytical method based on HPLC-UV, developed by Codex Committee on pesticide residues was employed for the analysis of mancozeb residues from vegetables samples (tomatoes and cabbages) collected from Bukavu region in DRC. The laboratory analysis showed a Limit of Detection of 0.01 mg/kg, the recoveries ranged from 73.5 to 82.1 % for cabbages and 64.0 to 66.9 % for tomatoes. The concentration of the residues expressed as mancozeb (the factor conversion for mancozeb derivative = 1.13) in tomatoes varied (in mg/ kg) from no detectable values (ND) to 1.33 for Kamanyola, ND to 1.87 for Nyangezi, 1.44 to 3.99 for Katana, 1.54 to 4.06 for Miti and ND to 4.65 for Mudaka samples. The average values ± SD (Standard Deviation) in mg/ kg for the five study sites were 0.89 ± 0.35, 1.31 ± 0.44, 2.48 ± 1.02, 2.71 ± 0.82 and 3.25 ± 1.25 respectively. ····· 10361119320
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The rapid progress in the field of organic conducting materials has found possible applications for sensors and molecular electronics. Among them both conducting polymers and carbon nanotubes, specifically Single Walled Carbon Nanotubes and Multi Walled Carbon Nanotubes, are good candidates for these applications. Their associations can lead to the synthesis of materials called nanocomposites which resemble the whole physical and chemical properties of the starting ones. This book is therefore focused on the fabrication of nanocomposites materials, based on polyaniline derivatives and multi-walled carbon nanotubes, by means of standardized oxidative polymerization, and the subsequent characterizations by different techniques to asses the physical and chemical properties of the synthesised materials. ····· 10361119233
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The design and synthesis of nucleoside analogues as potential anticancer and antiviral agents is a very dynamic field of research. The core objective of this intense research is amendment in sugar and base moieties to make the nucleoside more apt for therapeutic response. The drug industry now a day is giving more emphasis on chiral molecules as these are much more specific to the target. Even the two enantiomers of a particular substrate may interact differently with different chiral pockets and show different kinds of activity. So it is imperative to devise routes to nucleosides, which yield desired molecular structures with specific stereochemistry. Carbohydrates with six chiral centers are nice starting materials for this purpose. Among the carbohydrates, D-glucose is a useful chiral template, as it is cheap, easily available. Three chapters of this book is dealing with the use of various simple and useful reactions on glucose molecule to synthesize chiral carbocyclic (Chapter 1), heterocyclic (Chapter 2) and bicyclic (Chapter 3) nucleosides and analogues. ····· 10361119084
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Over the past half century, the absolute configuration of thiopeptide antibiotics such as Thiocillin I has baffled chemists until the first correct synthesis of Micrococcin P1 in 2009. At this point we had to answer two questions - first, does the absolute configuration hold true for its natural analogues Second, can we design a more efficient synthesis of the tri-substituted pyridine core The current synthesis sheds light on these problems especially for medicinal chemists who wish to explore the SAR for the purposes of drug development. ····· 10361118941
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book focuses on the structure elucidation of pentacyclic triterpenes using to two essential techniques, Nuclear Magnetic Resonance and Mass Spectrometry. The Carbon-13 NMR data of most of the classes of pentacyclic triterpenes and their mass fragmentation pattern is provided and the characteristic 13C NMR signals and mass fragmentation peaks have also been described. Thus by comparing the data of an unknown pentacyclic triterpene with the data of the known pentacyclic triterpenes provided in this book may help to narrow down the search for the structure of the compound. ····· 10361118751
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Medicinal Chemistry, an evolving andinterdisciplinary field, plays a key role inpharmaceutical research. It involves the study oftherapeutically active compounds.This text bookprovides a concise introduction to medicinalchemistry suitable for undergraduate students. Thebook focuses mainly on examples and illustrates theprinciples and mechanisms with the liberal use oftables and figures. Each chapter begins with a briefintroduction to the disease, drug classification,detailed subsections on different classes thatinclude mechanism of action, therapeutic uses andstructure activity relationships (SAR), among others. ····· 10361118654
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In this thesis, novel oxime ligands, bearing hydrazone, thiosemicarbazone and semicarbazone side groups which have not been described in the literature previously were synthesized and investigation of metal extraction and antibacterial properties. Their complexing properties were studied by the liquid-liquid and solid-liquid extraction. The ligands have been prepared and tested in vitro against different microorganisms in order to assess their antibacterial properties. ····· 10361118621
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The work represented in the book is divided into five chapters in first chapter deals with derivatives of 4-amino coumarin. Second chapter developed a novel, rapid and efficient methodology for the synthesis of imidazo[1,2-a]pyridine derivatives. Third chapter deals with 1,3,4-oxadiazole. Fourth chapter modify known antiepileptic drug valproic acid to convert into various analogs. Fifth chapter deals with the biological activity of newly synthesized of 4-amino coumarin derivatives. ····· 10361118537
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The phytochemical screening of the plant (Cissus multistriata) revealed the presence of important phytochemicals, such as saponins, steroids, flavonoids etc. Important glyconutrients such as xylose, fucose,mannose and galactose have been detected to be present in this plant. Based on the nutrients resident in this plant it is hoped that it can serve as better dietary supplement. From the result of this investigation, this plant does not possess anti diabetic properties as claimed by the users, but have demonstrated the potential of hypocholesterolemic capacity, hence can be used in the management of cardiovascular diseases. It is inferred from this work that the detected glyconutrients are contributory to the antimicrobial activities of this plant. The plant extract can be used in the management of hemolytic anemia and that the herbal extract is relatively safe at lower doses, exerts weak inhibition to Artemia salina (brine shrimps) hence cytotoxicity is quite low. The plant exhibited great antioxidant activity with the unripe fruit and stem having the highest. ····· 10361118508
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Cyclic peptides are structurally diverse molecules exhibiting a broad spectrum of biological functions with inherent physiological advantages, ranging from insecticidal and antimicrobial to anti-inflammatory and immunosuppressing activities. The synthesis and study of cyclic peptide analogues thus presents a powerful advance in the design and discovery of novel peptide drugs. During the past 20 years, phakellistatins 1-18 have been isolated as prolin-rich cyclic peptides with potent activities against various cancer cell lines. The solid-phase total syntheses of two members of the series, phakellistatins 12 & 13, along with alanin-scanning analogues of phakellistatin 13 was carried out to verify the structure and bioactivities of the natural products. Interestingly, the synthetic peptides were found to be identical in structures to their natural counterparts, whereas the biological activity could not be reproduced. The present study is thus valuable for the readers interested in various methods of SPPS and structural characterization of peptides. Furthermore, the results of the present study highlight the potential uncertainty with the biologically active natural products. ····· 10361118463
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This thesis reports the design and synthesis of guanidinium-based receptors as multiple hydrogen bond hosts for molecular recognition of anions with a special emphasis on small anions such as nitrate and the anti-inflammatory drug Naproxen.Despite its significant involvement in environmental pollution, little attention has been given to nitrate by supramolecular chemists. This books reports the design of several macrocycles combining a guanidinium and two urea moieties for an optimal complement of size, charge and binding sites to nitrate. Naproxen is the only Non-Steroidal Anti-Inflammatory drug (NSAID) marketed as a pure enantiomer. The industrial preparation of the drug involves the synthesis of the racemic acid followed by a resolution process to afford the desired compound (resolution accounts for two thirds of the production costs). Here, we propose as an alternative the use of a physical separation method (liquid-liquid extraction) employing a chiral receptor. ····· 10361118305
····· lezzter Preis 44.10€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray An extensive literature assessment is done and it is obvious that the methods are accessible for Ranitidine. HPLC is very expensive instrument and are not available in every laboratory. While UV/Visible spectrophotometer is a common instrument of all pharmaceutical analytical laboratory. Spectrophotometric analysis methods available for Ranitidine are tedious, time consuming and not much sensitive in term of precision and accuracy. It becomes essential to develop new rapid and cost effective methods that spectrophotometric determination would be simple, accurate, precise and sensitive. The newly developed analytical methods can be used in research institutions, Quality control in pharmaceutical industries, Approved testing laboratories and Bioequivalence studies. ····· 10361118259
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray As a model for interactions present in the active site of orotidine-5 -monophosphate decarboxylase (ODCase), we investigated the effects of substrate destabilization by a nearby negative charge and stabilization of the carbanion intermediate, due to hydrogen bonds to the carbonyl groups (O-2 and O-4) of orotic acid and its decarboxylation product, using ab initio calculations. Results from these models were comparable with available data, suggesting that the magnitude of the decarboxylation rate enhancement depends on a combination of the charge distance and hydrogen bonding effects. We found that the dipole moment of the proton donor may also play a significant role, implying that the key to the rest of the catalysis lie within the specific interactions of the substrate and the surrounding residues. ····· 10361117986
für 26.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Este texto recoge los resultados de investigación de la actividad antioxidante de los flavonoides aislados de las hojas y corteza de Bauhinia kalbreyeri Harms, conocida en la etnoafarmocología colombiana como `casco de vaca`. Los resultados observados en la aplicación de las distintas pruebas de actividad antioxidante muestran que en gran parte la actividad biológica evaluada guarda relación con el contenido de compuestos fenólicos y a su vez, la corteza rindió el mayor contenido de este tipo de metabolitos secundarios, siendo el agua el solvente más apropiado para extaerlos. El trabajo fue desarrollado por integrantes del grupo de Investigación en Productos Naturales (GIPRONUT) de la Universidad del Tolima (Colombia, con el apoyo financiero de la Oficina de Investigaciones y desarrollo científico. ····· 10361117345
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray El presente trabajo se divide en tres partes. La primera parte se ha dedicado al estudio fitoquímico de especies endémicas del Rif, por ejemplo el abeto de Marruecos (Abies marocana) y la especie de tejo que crece en los bosques del norte de Marruecos (Taxus baccata), con especial atención a la búsqueda de metabolitos útiles para la semi-síntesis de productos de alto valor añadido. Posteriormente, se abordó el desarrollo de nuevos métodos de síntesis basados en metales de transferencia monoelectrónica, con especial atención a los complejos de titanoceno(III). En este sentido, la parte más extensa de la tesis se ha dedicado al desarrollo de nuevos métodos de formación de enlaces C-C en sistemas que combinan complejos de titanio con otros metales. Finalmente, se realizó un esfuerzo considerable para aplicar los nuevos métodos desarrollados a la síntesis y confirmación estructural de algunos metabolitos escasos en las especies forestales del Rif. ····· 10361117160
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray New materials are the lifeblood of solid state research and device technology. Contrary to what many believe, new materials are not usually discovered by device engineers, solid state theorists, or research managers they are mostly discovered by crystal chemists who are crystal growers. Some physical phenomena are only exhibited in single crystals and can only be studied and understood in single crystals. Thus the crystal grower - especially if he develops a proficiency in relating structure, bonding and other chemo-physical considerations to properties of interest is in a key position in determining the direction & success of solid state research and ultimately technology.There is a need for new lasers with exciting combination of light properties such as wide spectral tuning ranges & large bandwidth for communication systems. While a variety of materials have been studied for their NLO activity, the organic materials have been receiving the maximum attention because of their ultra fast response time, photo-stability and large first order hyper polarizability values.In this view some new organic compounds have been synthesised, grown, characterised, irradiated & discussed ····· 10361116107
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Synthesis, Characterization, Anti-Proliferation, Benzimidazole Derivatives, FTIR, HRMS, 1D, 2D NMR spectroscopy, X ray crystallography, benzylation, addition/elimination, cyclization reactions, o- vanillin, o-, m-, p-phenylenediamines, 2-benzyloxy-3- methoxybenzaldehyde, 2-amino-N-benzylidene benzeneamines, bis-Schiff bases, six , five membered illusory rings, tetrahedral mechanism or addition/elimination mechanism, breast cancer cell line MCF 7, colon cancer cell line HCT 116, MTT assay, cytotoxicity, and IC50. ····· 10361116046
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray On the basis of bis(1H-indol-5-yl)methane derivatives 2,2`-diethoxycarbonyl-bis(indol-5-yl)methane and 2,2`-diethoxycarbonyl-3,3`-bisdimethyl- bis(indol-5- yl)methane were obtained 3,3`- bisphenylpiperazinomethyl, 3,3`-biscyanomethyl derivatives, tetracarboxylic acid and its tetraethylester. And on the basis of 2,2`- diethoxycarbonyl-3,3`-diformyl-bis(indol-5-yl)methane bisisonicotinoylhydrazone. The following reactions were studied: piperazinomethylation reaction of 2,2`- diethoxycarbonyl-bis(indol-5-yl)methane, alkylation reactions of phenylpiperazine and KCN with 2,2`- diethoxycarbonyl-3,3`-bisdimethylaminomethyl- bis(indol-5-yl)methane, alkaline hydrolysis and acid alcoholysis reactions of 2,2`-diethoxycarbonyl-3,3`- di(cyanomethyl)- bis(indol-5-yl)methane. The corresponding compounds were obtained. The condensation reactions of 2,2`-diethoxycarbonyl-3,3`- diformyl- bis(indol-5-yl)methane with isonicotinoylhydrazide, aniline and its mono- nitroderivatives. The structure of the obtained compounds was established on the basis of spectral data. ····· 10361115736
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Synthetic oligonucleotides act as a fuel for engine of modern molecular biology. One of the major application of these biomolecules is in construction of oligonucleotide microarrays or biochips. Microarrays are monolithic, flat surfaces that bear multiple probe sites and each bear a reagent whose molecular recognition of a complementary molecule can result to a signal that is detected by an imaging technology, most often fluorescence. Large-scale genotyping, gene-expression profiling, and disease diagnosis are some of the main applications of biochips. At the present time, this technology of arrayed nucleic acids is employed in many areas, from genetics to molecular medicine to industrial production. This book will give you an insight to efficient strategies for microarray fabrication using modified/unmodified oligonucleotides and glass microslides. In addition, chemical reagents for the estimation of functional group density on solid supports are discussed. ····· 10361115588
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Acridone derivatives containing 1, 3, 4-oxadiazole and 1, 3, 4-thiadiazole rings are synthesized.Diphenylamine-2,4`-dicarboxylic acid [1] is obtained in a high yield by refluxing a mixture of 4-aminobenzoic acid and 2-chloro benzoic acid in the presence of catalytic amount of copper oxide. 9(10H)-Acridone-2-carboxylic acid [2] is synthesized in ring closure reaction by heating compound [1] in sulfuric acid followed by basic hydrolysis.Reaction of compound [2] with thiosemicarbazide in the presence of phosphorus oxychloride gave 2-[5-amino-1, 3, 4-thiadiazole-2-yl]-9(10H)-acridone ····· 10361115566
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Organophosphate esters have wide scope in insecticides, herbicides and plasticizers industries etc. Since the organophosphate compounds have been reported biologically active, therefore it is essential to study the organophosphates systematically at all the faces of reactions. Now the emerging concern is the effect of Organophosphate esters on the environment. Many organophosphates are potent nerve agents, functioning by inhibiting the action of acetylcholinesterase (AChE) in nerve cells. Organophosphate esters are one of the most common causes of poisoning worldwide, in agricultural areas. This study is very important in present scenario. For researchers it is essential to pay desirable attention to the effect of each factor, as the rate of reaction is influenced by a number of factors such as ionic strength, concentration, temperature, solvent and catalyst etc. This book provides the detailed kinetic study on the hydrolysis of these Organophosphate esters. This study should be useful to Environmental Scientists ····· 10361115226
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Polypyrrole (PPy) as a conducting polymer has potential applications in electrical and electronic devices. This book therefore aimed to produce novel polypyrrole fibres via the development of nanostructured conducting polypyrrole by fibre spinning of PPy and to investigate the formed fibres for applications such as actuators, e-textiles, batteries, sensors and biomedical areas. As a result polypyrrole fibres have been produced for the first time. Subsequent work sought to improve the properties of these first generation PPy fibres by increasing the molecular weight, addition of carbon nanotubes (CNTs) and addition of a supporting polymer (alginate). The use of the host polymer also enabled a new fibre spinning method to be developed that included an in situ polymerization process. The highest conductivity and Young`s modulus of any conducting polymer based fibre reported to date was obtained by incorporating PPy into a CNT yarn. In summary, a range of novel fibres PPy materials have been developed for possible use in applications such as actuators, sensors, artificial muscles, batteries and biomedical applications. ····· 10361115206
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In order to conserve plant species, there is a need to highlight other important sustainable exploitations of these species by documenting and validating the uses. This study was undertaken to determine the oil content and its characteristics for selected 11 wild plants species chosen because they are among the dominant plant species in the primary forest of Kahuzi-Biega National Park and surrounding areas in Kivu Region, Democratic Republic of Congo. The plant seed oil contents reported in this study were found high compared to some food crops such as soybean and olive seed. Some of the oils of the plants studied here have potential for use in food because of their essential fatty acids content and some other oils showed good promise in use in cosmetics. These plant oils may also be sources for very long chain fatty acids which also have important chemotaxonomic significance. ····· 10361115198
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Crystal structure plays an important role in determining chemical and mechanical properties of polymers.Elucidating the crystal structure of polymers is extremely difficult particularly in obtaining a sizeable crystal for XRD analysis.This work prove the viability of computer modelling approach interfaced with simulated XRD diffraction. High-performance aromatic polymers based on the 4,4`-biphenylene, 1,3-phenylene,isophthaloyl bis(4,4`-biphenylene) and p-terphenyl units were synthesized and their crystal structures investigated. The polymers show extreme thermal stability and are insoluble in almost all organic solvents.Oligomer and polymer crystal structures were constructed using computational modelling and quantitatively compared with simulated diffraction via Rietveld Analysis. Molecular mechanics force-fields were optimised from conformational and crystal packing data determined from oligomeric analogues by X-ray single-crystal and powder diffraction methods. ····· 10361115195· 1 ·· 2 ·· 3 ·· 4 ·· 5 ·· 6 ·· 7 ·· 8 ·· 9 ·
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