für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Rice straw is an alternative source for the production of cellulose pulp and some other useful materials such as xanthated cellulose. The conditions of preparation (pulping, bleaching and xanthation) and factors affecting the main properties of the produced cellulose pulp and xanthated cellulose (the effect of alkali concentration, time of pulping and weight / volume ratio when boiling) are intended. The resulting intermediate products as well as the final products, were characterized and compared at each experimental step. The IR absorption spectral analysis were undertaken according to different methods (Saad et. al., base line technique, back ground and Pirlot methods) Agricultural wastes (cellulosic) treatment and characterization using different methods and analyzing the figures of scanning with electron microscope. ····· 10361102673
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The first aim of this study is to evaluate the radiological impact of the oil refining process to obtain an extensive view to the radiological bidden of the petroleum industry in Egypt. The second aim is intended to set-up working guidelines for the workers in the companies and regulators with an understanding of occupational and environmental risks from TENORMs generated in oil refining facilities in Egypt beside the disposal of sludge without the treatment to environment. The last aim of the study is the recovery of the hydrocarbon content of the sludge using petroleum cuts and solves the problems of the disposal into environment The overall cost as well as time involved for recovery and the disposal of hydrocarbon residue has been decreased. Capillary gas chromatography was used to estimate the economic value and reuse of recovered oil. ····· 10361102629
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Catalytic Oxidative Cracking of n-Hexane is investigated as an alternative route to steam cracking for light olefin production. Light olefins are the building blocks for the petrochemical industry. In a rapidly growing world market for the production of new synthetic materials (plastics), demand for these petrochemicals is tremendously increasing. Propylene and butylene yields from current production technologies (steam cracking, fluidized catalytic cracking (FCC), oxidative dehydrogenation (ODH)) are insufficient to satisfy the growing demand, urging interest in alternative processes for light olefin production. This PhD research work aimed towards achieving higher selectivities to both propylene and butylenes than steam cracking. Mo/Li/MgO is an efficient catalyst for oxidative cracking of n-hexane. The catalyst has minimal red-ox activity and results in reasonably high yields of olefins. Furthermore, plasma induced experiments resulted in higher yields of olefins. ····· 10361102612
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Sodium silicate from rice husk ash was functionalized with different silylating agents to produce silica with CH2 Cl (labelled as RHACCl), CH2 NH2 (labelled as RHAPrNH2) and CH2 SH (labelled as RHAPrSH) end groups via a novel one pot synthesis. Saccharine (Sac) and Melamine (Mela) were immobilized onto RHACCl to form RHAC-Sac and RHAPrMela. The functionalized CH2 SH group in RHAPrSH was oxidized to sulfonic acid, CH2 SO3H (labelled as RHAPrSO3H) with hydrogen peroxide at room temperature. The catalysts showed good textural and structural properties. RHAC-Sac, RHAPrMela, RHAPrSO3H, RHA Blank (as control) as well as homogenous Sac and homogenous Mela were used as catalysts in the esterification reaction. The catalytic activity was found to follow the sequence: RHAPrSO3H RHAPrMela homogenous Sac RHAC Sac homogenous Mela RHA Blank. The catalysts were easily regenerated and could be reused several times without loss of catalytic activity. ····· 10361102498
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Molecules well known for their chelating properties are clubbed with the molecules well known for their antimicrobial activity. A resultant novel molecule is found to have retained both the parental properties with a reasonable thermal and chemical stability. In this text, we have presented the outcome of research work done by Bhargav Trivedi for his PhD thesis submitted to Hemchandracharya North Gujarat University, Patan, India under the supervision of Dr. Piyush J. Vyas. ····· 10361102078
····· lezzter Preis 49.00€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Specimens of ZrB2 containing various concentrations of SiC, TaB2, and TaSi2 were pressureless-sintered and post-HIPed to theoretical densities. Oxidation resistances were studied by scanning thermogravimetry over the range 1150 - 1550 C, and isothermal thermogravimetry at 1200 - 1900 C. Most silicon-containing compositions formed a glassy surface layer, covering an interior oxide layer. This interior layer was less porous in tantalum-containing compositions. Small concentrations of TaB2 additions were more effective at increasing oxidation resistance than equal additions of TaSi2. The benefit of these additives was related to the formation of fine particles of ZrO2 and TaC during oxidation. These particles resisted wicking of their liquid/glassy borosilicate encapsulation. With increasing TaB2 or TaSi2 concentration, oxidation resistance degraded. In these cases, zirconia dendrites appeared to grow through the glassy layers, providing conduits for oxygen migration. At 1700 C and above, a layer of ZrB2 devoid of SiC was argued to be from preferential removal of SiC by reaction of silica oxidation product with adjacent unreacted SiC to form escaping gases. ····· 10361101673
····· lezzter Preis 71.10€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The research work has been divided into two parts. In Part A, various di- and triorganotin(IV) compounds have been synthesized by reactions of R2SnCl2, R2SnO and R3SnCl with a stoichiometric amount of synthesized carboxylic acid. In Part B, various di-, tri- and chlorodiorganotin(IV) thiocarboxylates have been synthesized by the reaction of di- and triorganotin(IV) chlorides with thiocarboxylic acid in stoichiometric amount in dry toluene under reflux conditions. The structural assignments were made on the basis of spectral techniques such as FT-IR, 1H, 13C, 119Sn NMR, mass spectrometry and XRD which ascertain the tetrahedral environment around the tin atom in solution, while penta or hexa coordination is found in the solid state. Biological activity tests of the synthesized carboxylates and thiocarboxylates were made against various medically important bacteria, fungi, insects and leishmania. Most of the compounds were found to show activity with a few exceptions. These compounds were also evaluated for their cytotoxicity using the brine-shrimp lethality bioassay method. Only few of the compounds were found to be nontoxic. ····· 10361101068
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Azosulfonamide rhodanines are widely used as analytical reagents. They are capable of forming chelates with many of metal ions. The formed chelates are distinguished by their stability due to the formation of chelate ring. From the structural point of view, these were considered as metal indicators since they posses functional groups capable of chelate formation joined directly to the central metal ions.In the present investigation, proton-ligand stability constant, pKH, of azosulfonamide rhodanine compounds will be determined potentiometrically in 20% (v/v) DMF-water mixture. The metal-ligand stability constantsof the compounds with Fe2+, Cd2+, Fe3+,UO2 2+ and Zr4+ will be determined potentiometrically. Stoichiometeries of the complexes formed in solution will be determined potentiometrically. The enthalpy change, the entorpy change, and the free energy change, of the compounds and their complexes will be evaluated and discussed. The structure of these chelates will be elucidated from the study of their elementalanalyses, infrared spectra, 1H-NMR spectrum, electronic spectra, magnetic measurements and ESR. ····· 10361100964
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Solar light driven water oxidation photocatalyst Bi20TiO32 has been successfully synthesized through sol gel process. Photocatalytic activity of Bi20TiO32 for oxygen evolution using silver nitrate as sacrificial agent under UV light and visible light irradiation have also been studied and enhanced by the addition of co-catalyst iridium oxide and platinum to the photocatalyst. Furthermore, overall water splitting reaction using Bi20TiO32 in combination with CuFeO2 has also been conducted by conventional and modified Z-scheme process in both single and twin reactor. Photo-reduced graphene oxide and co-catalyst iridium oxide and ruthenium have been used to enhance photocatalytic activity water splitting. ····· 1036198822
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The equilibrium constants for trivalent metal ions (Fe3+ and Cr3+) and divalent metal ions (Cu2+, Ni2+ and Co2+) with ligands gallic acid, L-norleucine and nicotinic acid were studied by using pH-potentiometric titration in aqueous solution at 25oC (I = 0.15M NaNO3). In order to determine the stability constant values, the protonation constants of free ligands were also determined. The complexation model for each system was established by the software program HYPERQUAD 2008 from potentiometric titration data. UV spectrophotometric measurement was carried out to confirm the complex that formed in each solution qualitatively. The phenomenon that occurred in each system was discussed. In terms of the nature of metal ion, the trend of stability constant is Cu2+Ni2+Co2+, which is in agreement with the Irving-William order of divalent metal ions. For trivalent metal ions, stability constant of Fe3+ is always higher than that of Cr3+. In terms of the ligand, the system that contains gallic acid as a ligand is more stable than the other systems that do not contain gallic acid. ····· 1036198757
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This study on the sites of coordination, nature, and mode of bonding of Fe, Cu, Cd, and Sn in different types of algae, employed FT-IR, Mössbauer and NMR to throw some light on the structural conformations of the formed metal ion moieties. The metal ion uptake by chlorella vulgaris exhibited a linear relationship with ionic radii, where ion exchange dominates at low concentrations of Cu, whilst electrostatic binding showed to be the main mode of binding at high concentrations. Changes in bond vibrations of carboxylates confirmed their dominance as binding sites. In addition, 113Cd NMR spectra suggested the participation of -N and -OH containing ligands, and a six-coordinate structure. The Mössbauer spectra of Fe-57 revealed unequal bond lengths between Fe(III) ion and the bonded ligand atoms, and marine algae exhibited a reducing ability into Fe(II) moieties of low octahedral symmetry. Three polyhedral geometries around Sn-119 tetravalent moieties are in equilibrium, and are concentration dependent. The alga chlorella vulgaris restored part of its lost capacity towards metal binding, upon reuse, by aqueous ethanol metal ion solutions which increased with decrease in ionic radii. ····· 1036192441
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Among the transition metal oxides, tungsten bronzes have attained considerable attention due to their chemical, electrical and optical properties which depend on the type of alkali-metal atom and its composition. The term tungsten bronze is applied to the non-stoichiometric compounds of general formula MxWO3 (0 x 1), where M is an alkali-metal atom. The common structural feature of these materials is the WO6 octahedra which are repeated along three directions through corner sharing. This structural arrangement provides various kinds of tunnels, which are at least partly occupied by alkali metal atoms. These materials undergo one or more structural phase transitions depending on the content of alkali metal x. The main part of this book is focused on LixWO3-PTB, in order to explore the stability field in the conventional solid state synthesis techniques and to investigate in particular their spectral properties. For polarised micro reflectivity, single crystals of LixWO3 are also prepared by chemical vapour transport method. The spectral and structural properties of Nb-doped and Mo-doped alkali metal tungsten bronzes, AxMyW1-yO3 (A = Li, Na, Cs and M = Nb, Mo) are also discussed. ····· 1036192306
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Weakly-ferromagnetic hematite is a cheap, environmentally friendly and thermodynamically stable iron oxide, and 1D hematite nanorods (NRs) have been studied for a wide range of applications because their magnetic properties are greatly dependent on NR size and shape. Herein, the hydrothermal synthesis (HS) of hematite NRs is investigated using a combination of analytical techniques. Development of a novel, valve-assisted, hydrothermal pressure vessel, which allows for the rapid quenching of hydrothermal products as a function of reaction time and known reaction temperature, provided fundamental insight into the anisotropic crystal growth mechanism of the acicular hematite NRs. The hematite NR growth mechanism was found to be a two stage process: 1) the growth and dissolution of intermediate -FeOOH NRs, alongside precipitation of primary hematite nanoparticles (NPs) and 2) the agglomeration and coarsening of primary hematite NPs into hematite NRs. The investigation of rapidly quenched -FeOOH and hematite HS reaction products, heat treated in situ within a transmission electron microscope, provides direct evidence for the hydrothermal growth mechanism of lenticular hematite NRs. ····· 1036191896
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In 1959, Richard P. Feynman gave a famous talk entitled There s Plenty of Room at the Bottom in a meeting of American Physical Society conducted at Caltech, USA. Feynman discussed his vision, building of objects atom by atom or molecule by molecule. This was the first idea and constitution of nanotechnology . Hereafter, nanotechnology has been attracted considerable interests in materials science, which is driven by the expectations concerning the application of nanomaterials in many technological applications as a forthcoming generation of functional materials for the new century. Within the last decade, nanoscience and nanotechnology have been considered as the leading research area in the physical and life sciences and engineering. This book consists of synthesis and characterization of coated magnetic spinel nanoparticles by various solution-based processes including hydrothermal, surfactant-assisted, sonochemical, gel-to crystalline, thermal decomposition and co-precipitation methods. Structural, morphological, spectroscopic, magnetic and electrical properties of the spinel nanoparticles were characterized by XRD, FTIR, TEM, SEM, EPR, TGA, and conductivity measurements. ····· 1036191832
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Landfill leachate with arsenic (As) contamination poses a threat to Florida aquifer because of the nature of the geology of the State. Florida sits directly on limestone which also hosts the main Florida aquifers. But the underlying rock and/or soil dissolve(s) away when the environmental pH becomes acidic. This results in sinkhole formations and is of a great concern especially, in areas of landfill locations. There is a potential of leakage of the leachate from the landfill into the aquifers threatening the quality and safety of the groundwater. In the United States, Class I landfills are classified as non-hazardous and contain materials such as woods and other construction materials. However, the leachate from the Class I landfills sometimes contain Arsenic of significant concentrations. At North Polk County in Florida, leachate from Class I landfill, was treated onsite by coagulation, precipitation and filtration. Occasionally when Arsenic was detected, the leachate was shipped and treated at nearby Waste Water Treatment which was expensive. This work evaluates a possibility of adopting adsorption process in fixed bed which is comparatively less expensive and sustainable ····· 1036191551
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This work reports some original and significant contributions on chiral coordination complexes. Complexes of chiral amino alcohols based Schiff base ligands with biologically and catalytically important metal ions have been developed and studied with respect to their structural, spectroscopic, supramolecular and catalytic properties. The importance of chiral amino alcohol based Schiff base ligands in coordination chemistry is briefly discussed in the introduction chapter. Synthetic details and spectroscopic characterization data of some new chiral Schiff base ligands and their metal complexes are presented in chapter two. Detailed studies on a series of biologically and catalytically relevant chiral Mn(IV) complexes form the content of the third chapter. A series of interesting mixed valence multinuclear cobalt complexes of chiral amino alcohol based ligands has been described in chapter four. Studies on some chiral copper complexes highlighting their structural and supramolecular properties are presented in fifth chapter. Finally, the work is concluded giving an overall summary as the sixth chapter. ····· 1036191357
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Vanadium has been reported to be an essential bio-element for certain organisms, including tunicates, bacteria and some fungi. This book aimed to describe the coordination chemistry of vanadium with biologically relevant ligands and presents synthesis of oxo, dioxo and oxoperoxovanadium(V) complexes. Most common oxidation states are +IV and +V and generally stabilized through V O bond. Oxocations [VO]2+, [VO]3+ and [VO2]+ are most common for biological systems. The development of structural and functional model complexes of vanadium haloperoxidases is the key motive of vanadium chemistry and some of the complexes can be considered to be structural models of haloperoxidases. The model character also extends to functional similarities, in that they catalyse the oxidation, by oxidant, of sulfoxide, styrene, cyclohexene, phenol, trans-stilbene etc. Vanadium complexes have also been found to catalyze the oxidation and epoxidation of various organic substrates. Some of the complexes have also been tested for their antiamoebic activity. ····· 1036188662
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The present book primarily deals with the lower rim substituted calix[4]arene derivatives and their metal ion complexes, and the biomimetic and biological studies of these complexes. Broadly, the book could be divided into the following three parts: (i) The K+ was found to act as template in the formation of calix[4]arene tetra-amide derivative exclusively, with the generation of calix[4]arene-monoanion and the structure of this has been characterized by single crystal XRD study. (ii) Metal ion complexes of p-tert-butylcalix[4]arene-diacid with Mn(II), Mn(IV), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Sn(IV) have been discussed. Co-administration of lead and tin complexes on porphyrin metabolism, oxidative stress and distribution of metal ion concentration in blood and soft tissues in rats have been evaluated. (iii) Anthracene anchored derivatives of p-tert-butyl-calix[4]arene were subjected to the binding studies with the divalent metal ions. Based on the photo-physical studies, an imine-based derivative were found to act as a chemosensor for Fe(II)and Cu(II) ions. ····· 1036188261
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In recent years, air pollution due to the hazardous exhaust gases is a serious problem with harmful effects on plants, animals, human health, as well as causing global warming and climate change. Therefore, development of scalable and inexpensive nanosensors for highly sensitive, selective detection and monitoring of toxic gases is extremely important in improving environmental quality and protecting humans from over-exposure to such dangerous agents. One of the methods to improve the gas sensors performances is using the nanomaterials, such as nanoparticles, nano thin films, nanorods, and nanowires. Of those nanomaterials, nanowire structures are of interested due to their two quantum-confined directions while leaving one unconfined direction for electrical conduction, making them suitable for resistive-type gas sensor applications. In this content, I introduce the nanowire structures for gas sensor applications: form materials synthesis to practical devices. I hope you will find that this book provides useful information in the field of gas sensors. ····· 1036187306
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book deals with some modern methods used in the synthesis and characterization of transition metal complexes. It is written primarily to stimulate the interest of students in metallo-organic chemistry and spectroscopy as well. The book is contained much useful spectral data in the form of tables and spectra. It contains a number of electronic, IR and EPR spectra, so the reader who is not familiar with these techniques can see how the spectra actually appear. It begins with a general introduction of applications of transition metal complexes in different fields. In subsequent chapters the detailed study regarding the synthesis and physicochemical characterization of bivalent transition metal ions [Cr(III), Mn(II), Co(II), Ni(II) and Cu(II)] complexes derived from 2-methylcyclohexanone semicarbazone and thiosemicarbazone using modern techniques like elemental analysis, magnetic moments and conductance measurements and spectroscopic (Electronic,IR, EPR ) studies is discussed. The geometry of synthesized complexes is emphasized. The book is intended to be useful to new metallo-organic researchers. ····· 1036187283
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The work described in this thesis concerns the filling of Single-Walled Carbon Nanotubes (SWNTs) with semiconductor compounds (HgTe, HgxCd1-xTe, InSb, SnSe). Once successfully introduced into the SWNTs, the fillings were structurally analysed via focal series restoration High Resolution Transmission Electron Microscopy (HRTEM). For each system, models were proposed, simulated and compared with original restored phase images. ····· 1036187267
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The ability of plasticizers and superplasticizers to reduce the water-cement ratio without changing the workability of concrete is a well-known fact. On the other hand, they may improve and / or facilitate the conditions the conditions of cement handling. Thus in this thesis, the effect of the presence of two different water-reducing admixtures, namely, calcium lignosulfonate (CLS) and sodium salt of naphthalene formaldehyde sulfonic acid polycondensate (NFS) on the hydration process of each of C3A and B3A with gypsum was studied. ····· 1036187040
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Hydrogen can be produced by numerous techniques, with no emission of pollutants and green house gases. Hydrogen has a number of attractive advantages such as high energy density, non-toxic reaction products and abundant natural resources. Sodium borohydride has been considered as hydrogen storage material in the use of renewable energy sources on the way towards sustainable energy of the future. Via this research work, we studied the effect of different phosphorus compounds on the catalytic activity of ruthenium(III) acetylacetonate in the hydrolysis of sodium borohydride and on the kinetics of the catalytic hydrolysis. In addition, synthesis and characterization of ruthenium(III) acetylacetonato complexes containing two trimethylphosphite ligands were studied. Finally, isolation, stabilization and characterization of new ruthenium species (active catalyst), formed during catalytic hydrolysis of sodium borohydride starting with Ru(acac)3 and P(OMe)3, were discussed. ····· 1036186832
····· lezzter Preis 61.20€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Corrosion damages is the biggest item on the maintenance bill of reinforced concrete (RC) structures. Chloride induced corrosion is the main cause for corrosion initiation. Chloride is the main cause for corrosion initiation in RC. Understanding the corrosion process and the parameters which influence the susceptibility for corrosion initiation, is essential for reducing the cost of corrosion in modern buildings. This book presents the theory of corrosion in reinforced concrete and describe an investigation of the relationship between the micro-structure of the interfacial transition zone (ITZ) between the concrete and the embedded steel and the chloride concentration for corrosion initiation (chloride threshold). It includes a complete description of the method used in the investigation, results, and comprehensive discussion. ····· 1036125285· 1 ·· 2 ·· 3 ·· 4 ·· 5 ·
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