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The synthesis and applications of the peptides are gaining increasing popularity as a result of the developments in biotechnology and bioengineering areas and for a number of research purposes including cancer diagnosis and treatment, antibiotic drug development, epitope mapping, production of antibodies, and vaccine design. The use of synthetic peptides approved by the health authorities for vaccine, for cancer, and in drug delivery systems is increasing with these developments. The aim of this book chapter is to review the recent developments in the use of peptides in the diagnosis of drug and vaccine systems and to present them to the reader with commercially available illustrations. more...

Colorimetry is the determination of colors, as name indicates. This method can use for to find out the concentration of compound (solute) in a colored solution in terms of chemical analysis (solvent). We frequently need to quantify the quantity of a specific component in a combination or the concentration of a solution during scientific activity. The trick is to determine the color differences between various combinations and their absolute values. This is more instructive and scientifically valuable than relying on subjective judgments like the color of the solution. Colorimetry is the measurement of colors, as the name implies. It is the measurement of the concentration of a certain compound (solute) in a colored solution in terms of chemical analysis (solvent). We frequently need to quantify the quantity of a specific component in a combination or the concentration of a solution during scientific activity. The trick is to determine the color differences between various combinations and their absolute values. This is more instructive and scientifically valuable than relying on subjective judgments like the color of the solution. Colorimetry is used in a digital image-based (DIB) approach for determining active medicinal components. A computerized scanner with a controlled light intensity was connected to the detector. Different histograms were used to transform the photos. The colorimetric analysis of digital images provided for an easy-to-use and ecologically friendly method. more...

Global phase diagrams (GPD) of binary mixtures in phase equilibria modeling are analyzed. The mapping of the global equilibrium surface in the parameter space of the equation of state (EoS) model provides the most comprehensive system of criteria for predicting binary mixture phase behavior. One may obtain the relationships for azeotropic boundaries from the global phase diagram [A (azeotrope) and H (hetero-azeotrope)] regions. Analytical expressions to predict azeotrope and double azeotrope phenomena in terms of critical parameters of pure components were derived using global phase diagram. The problem estimations of phase behavior modeling under the uncertainty are formulated applying the Pareto-optimum parameter and different (crisp and fuzzy) convolution schemes. The Pareto-optimum parameters in the Redlich-Kwong equation of state used different conflicting data sets (simultaneous description of the phase equilibria and critical line data in binary mixtures, thermodynamically consistent description of the inhomogeneous data). Ionic liquids (ILs) are one of prospective new working media for different environmentally friendly technologies. Practically undetectable vapor pressure is considered the ILs as ideal solvents replacing conventional solvents in the frame of a “green chemistry.” Combination of ionic liquids with conventional natural and synthetic refrigerants promotes the increasing efficiency of absorption processes due to nonvolatile ionic liquids (absorbents). more...

Titanium dioxide- (TiO2-) based nanomaterials have been widely adopted as active materials for photocatalysis, sensors, solar cells, and for energy storage and conversion devices, especially rechargeable lithium-ion batteries (LIBs), due to their excellent structural and cycling stability, high discharge voltage plateau (more than 1.7 V versus Li+/Li), high safety, environmental friendliness, and low cost. However, due to their relatively low theoretical capacity and electrical conductivity, their use in practical applications, i.e. anode materials for LIBs, is limited. Several strategies have been developed to improve the conductivity, the capacity, the cycling stability, and the rate capability of TiO2-based materials such as designing different nanostructures (1D, 2D, and 3D), Coating or combining TiO2 with carbonaceous materials, and selective doping with mono and heteroatoms. This chapter is devoted to the development of a simple and cost-efficient strategies for the preparation of TiO2 nanoparticles as anode material for lithium ion batteries (LIBs). These strategies consist of using the Sol–Gel method, with a sodium alginate biopolymer as a templating agent and studying the influence of calcination temperature and phosphorus doping on the structural, the morphological and the textural properties of TiO2 material. Moreover, the synthetized materials were tested electrochemically as anode material for lithium ion battery. TiO2 electrodes calcined at 300°C and 450°C have delivered a reversible capacity of 266 mAh g−1, 275 mAh g−1 with coulombic efficiencies of 70%, 75% during the first cycle under C/10 current rate, respectively. Besides, the phosphorus doped TiO2 electrodes were presented excellent lithium storage properties compared to the non-doped electrodes which can be attributed to the beneficial role of phosphorus doping to inhibit the growth of TiO2 nanoparticles during the synthesis process and provide a high electronic conductivity. more...

The synthesis of polycrystalline powder is a key step for materials sciences. In this chapter, we present the well-known methods of preparation of powders such as: solid-state reaction, sol–gel, hydrothermal, combustion, co-precipitation. Moreover, synthesis methods by arc furnace, by heating in a “high frequency” induction furnace and by high energy grinding are presented. The obtained powders could be defined by their purity, gain size, crystallinity, and morphology, which are influenced by the synthesis method. In addition, each method is dependent on some parameters like pH, concentration and temperature. more...

An important area to cope with in the implementation of technologies for the generation of energy from renewable sources is storage, so it is a priority to develop new ways of storing energy with high efficiency and storage capacity. Experimental reports focused on ZnO-graphene composite materials applied to the anode design which indicated that they show low efficiencies of around 50 %, but values very close to the theoretical capacity have already been reported in recent years. The low efficiency of the materials for the anode design of the Li-ion battery is mainly attributed to the pulverization and fragmentation of the material or materials, caused by the volumetric changes and stability problems during the charge/discharge cycles. In this chapter, we will discuss the development of composite materials such as ZnO-graphene in its application for the design of the anode in the Li-ion battery. more...

Bio-based surfactants are surface-active compounds derived from oil and fats through the production of oleochemicals or from sugar. Various applications of bio-based surfactants include household detergents, personal care, agricultural chemicals, oilfield chemicals, industrial and institutional cleaning, and others. Due to the stringent environmental regulations imposed by governments around the world on the use of chemicals in detergents, as well as growing consumer awareness of environmental concerns, there has been a strong demand in the market for bio-based surfactants. Bio-based surfactants are recognized as a greener alternative to conventional petrochemical-based surfactants because of their biodegradability and low toxicity. As a result, more research is being done on producing novel biodegradable surfactants, either from renewable resources or through biological processes (bio-catalysis or fermentation). This chapter discusses the various types, feedstocks, and applications of bio-based surfactants, as well as the industrial state-of-the-art and market prospects for bio-based surfactant production. In addition, relevant technological challenges in this field are addressed, and a way forward is proposed. more...

The prevention of solids formation and their deposition are major challenges to design and operate any subsea hydrocarbon production systems. One of the most challenging issues is the management of paraffin/wax. As the water depth increases, at the low temperatures of subsea conditions, hydrocarbons may precipitate as wax, which can solidify and restrict the flow. During shutdown of a subsea production system wax gel may form and solidify when a crude oil cools below its pour point causing operational problems from downhole to the processing facilities. The purpose of this chapter is to address the paraffin/wax formation and deposition issues to properly design a subsea production system consisting of pipe-in-pipe flowline and flexible riser under deepwater environment. A field specific example is presented to manage the wax formation/deposition and prevent paraffin/wax deposition risks in an effective way during the normal and the shut-in operations of the subsea production system. This study illustrates that the subsea hardware, such as water stop and equipment valves, along with the flowline, riser and jumper should be sufficiently insulated in order to prevent any cold spots in the production system, and achieve sufficient cooldown time for the shut-in operations. more...

A series of CoMo/γ-Al2O3 catalysts was synthesized by a reverse microemulsion method using 1-butanol as organic agent and cetyltrimethylammonium bromide as surfactant. The aqueous phase was used to form the solution of three corresponding Co, Mo and Al precursor salts. The materials were prepared at different solution concentrations in order to obtain different metal contents. All samples were characterized by X-ray diffraction, Raman spectroscopy, nuclear magnetic resonance and nitrogen physisorption. A chemical species distribution study was performed to establish conditions of preparation and the preponderant species present in solution as a function of pH. The materials obtained present high surface areas which decrease as the metal content (Co + Mo) increases. All samples with the exception of that with the highest metal content were amorphous as shown by X-ray diffraction. By Raman spectroscopy, Mo-O-Mo and MoO2t species were observed in all calcined samples. Mo-O-Co, Al-O-Mo, monomers and heteropolymolybdates were observed for the lower metal content samples, and the formation of CoMoO4 and aluminum molybdate species for the higher metal contents. These results suggest that the materials with lower metal loading have species that are easily sulfidable and provide high activity in hydrodesulfurization reactions. A model for the interaction of the species in the aqueous phase of the micelle is presented. more...

Conventional perovskite solar cells utilize a combination of a compact and mesoporous layer of TiO2 or SnO2 as the electron transport layer. This structure is vulnerable to massive loss of photogenerated carriers due to grain boundary resistance in the layer. In this chapter, we will discuss a potential electron transport layer that might drive higher power conversion efficiency, i.e., thin and single-crystalline 2D transition metal dichalcogenide. Because of their ultimate thin structure, they facilitate rapid electron transport and enhanced carrier extraction in the solar cells device. We will also discuss the current state of the art of 2D transition metal dichalcogenide atomic layer application as an electron transport layer in the perovskite solar cells as well as our recent attempt in this field. more...

The present chapter is devoted to the analysis of the obtained data on the high-temperature electrolytic production of high-purity lead from secondary lead in chloride melts. Kinetic parameters of electrode reactions were calculated, and the sequences of the metal dissolution from the double lead-antimony (Pb-Sb), lead-bismuth (Pb-Bi), and antimony-bismuth (Sb-Bi) alloys were determined. A long-term electrolysis of the antimony (battery scrap), bismuth (lead-bismuth), and lead-containing raw materials in the electrolytic cell of original construction with a porous ceramic diaphragm impregnated with the eutectic KCl-PbCl2 chloride electrolyte was performed. The anode lead alloy, containing 57.0 wt% of antimony and 36.0 wt% of bismuth, and cathode grade lead were obtained as a result of the electrolysis. The values of lead, antimony, and bismuth separation coefficients were calculated according to the values of the equilibrium potentials of the Pb-Sb, Pb-Bi, and Sb-Bi alloys. The values of separation coefficients were found to be 6.5·106–1.5·108 for a single stage at the lead extraction from the Pb-Sb and Pb-Bi alloys, which proves the possibility of a highly effective lead extraction. The value of Sb-Bi alloy separation coefficient ranges from 5.5 to 6.5, which testifies the complexity and low effectiveness of the separation process. An electrolytic refining of lead-bismuth and secondary lead, obtained from the battery scrap, was performed. more...

Friction reduction is imperative for improving the service life and energy efficiency of mechanical systems. Ion gels using ionic liquids (ILs) as swelling agents are expected to be stable gel lubricants owing to the high thermal stability and negligible volatility of ILs; they can maintain their swollen state even under harsh conditions. Therefore, we investigated two types of ion gels: an IL-substituted double-network gel (DN ion S-gel), in which the water in the DN hydrogel is replaced by the IL 3-ethyl-1-methyl-imidazolium ethylsulfate; and a DN ion gel containing N,N-diethyl-N-(2-methoxyethyl)-N-methyl-ammonium bis(trifluoromethylsulfonyl)imide (DEME-TFSI), where one of the polymer backbones is a network of poly(N,N-diethyl-N-(2-methacryloylethyl)-N-methylammonium bis(trifluoromethylsulfonyl)imide), an IL-type polymer based on our previous synthetic study of IL polymer technology. The DN ion S-gel and DN ion gel achieved compression strengths of 25 and 30 MPa, respectively, and were thermally stable until 196°C and 335°C (10% weight-loss temperature), respectively. The coefficient of friction remained stable and low (0.02) after repeated measurements under harsh conditions (high temperature or vacuum conditions), affirming the durability of the DN ion gel. more...

Chromatographic column is an essential part of a any HPLC separation, and significant progress has been made in developing columns with better performance to provide better separation, a shorter separation time, resilience to a wider pH range of the mobile phase, longer lifetime, use of lower volumes of mobile phase, etc. All these characteristics were achieved by the introduction of novel technologies and improvements of the older ones. These include smaller particle used to fill the column, more homogeneous spherical particles, core-shell particles, monolithic columns, more pure silica as a stationary phase support, use of ethylene bridge silica, a wider variety of active phases, use of mixed mode stationary phases, use of polymers as stationary phase, use of various endcapping techniques, etc. Miniaturization and progress in the instrumentation played an important role for the chromatographic column development. All these aspects are summarized in the present chapter. more...

The reduction of environmental impacts caused by emissions of greenhouse gases has become an internationalized goal. In this context the development of technologies capable of producing energy from clean or renewable sources has gained broad prominence, among them the fast pyrolysis is a type of thermochemical process capable of converting biomass and agroindustrial waste into a liquid product called bio-oil that has a wide range of applications in the bioenergy scenario. For this type of technology to be consolidated as an alternative source of renewable energy, economic, political and environmental incentives are necessary, as well as research development to improve the conversion processes, such as reactor types, logistics in obtaining and pre-treating potential biomass, improvement and conversion routes for bio-oil obtained in renewable biofuels or chemicals with higher added value. This chapter covers the fundamentals of thermal conversion of biomass into bio-oil and the most studied processes to convert bio-oil into a product with better properties, such as deoxygenation and energy densification. more...

Furfural, a five-membered heterocyclic aromatic hydrocarbon derivable from acid hydrolysis of sugar cane bagasse, maize cob, rice husk or any cellulose-containing material, is useful in the synthesis of a range of specialized chemical products. Its condensation with nitromethane in basic medium yields 2-(2-Nitrovinyl) furan. This functional group (nitrovinyl) has been documented as a potent anti-microbial agent against gram-positive and gram-negative bacteria, with more potency against the gram-positive strains. The reaction of urea and thiourea with furfural yields bisimines-1,3-bis[(E)-furan2-yl)methylene]urea, and 1,3-bis[(E)-furan-2-yl) methylene]thiourea respectively. The two compounds are good antimicrobial agents in addition to the latter as a potential dye for wool and cotton fabrics with different hues. Also the reaction between acetophenone and furfural (an aldehyde) in a basic medium yields the chalcone: (E)-3-(furan-2-yl)-1-phenylprop-2-ene-1-one. This chalcone has been confirmed as a good antifungal agent and wood-protector against termite attack. Thus, chemical modification of the aldehyde functional group of furfural to nitro, imine and chalcone groups imparted different activities on furfural. more...

Thiazoles belong to the group of azole heterocycles. They are aromatic five-membered heterocycles containing one sulfur and one nitrogen atom. In recent years thiazoles, their derivatives, and isomers have gained considerable attention because of their broad applications in different fields, such as agrochemicals, industrial, and photographic sensitizers. Also, they have pharmaceutical and biological activities that include antimicrobial (sulfazole), antiretroviral (ritonavir), antifungal (abafungin), anticancer (tiazofurin), antidiabetic, anti-inflammatory, anti-Alzheimer, antihypertensive, antioxidant, and hepatoprotective activities. The compounds containing thiazole moieties are a prominent structural feature in a variety of natural products, such as vitamin B and penicillin. Thus, in this chapter several types of thiazole-based heterocyclic scaffolds such as monocyclic or bicyclic systems synthesis and their biological activities studies are presented. Furthermore modification of thiazole-based compounds at different positions to generate new molecules with potent antitumor, antioxidant, and antimicrobial activities is described. more...

The study deals with the modelling and experiments of vertical solid-liquid turbulent flow with narrowly sized solid particles of average diameters equal to 0.125 mm, 0.240 mm and 0.470 mm, and solid concentrations by volume from 10% to 40%, called medium slurry. The physical model assumes that the slurry with solid particles surrounded by water is flowing upward through a vertical pipeline with solid concentrations from 10–40% by volume. Experiments with such slurries clearly indicated enhanced damping of the turbulence, which depends on the diameter of the solid particles. The mathematical model constitutes conservative equations based on time averages for mass and momentum. The closure problem was solved by taking into account the Boussinesque hypothesis and a two-equation turbulence model together with an especially designed wall damping function. The wall damping function depends on the average diameter of the solid particles and the bulk concentration. The predictions’ results were successfully compared with the measurements. The study demonstrates the importance of solid particle diameter and showed that using a standard wall damping function gives higher friction compared to measurements. The main objective of this study is to present a mathematical model for medium slurry flow in a vertical pipeline, including a specially designed wall damping function, and to demonstrate the influence of solid particle size on frictional head loss. The effect of mean particle diameter and solid concentration on frictional head loss has been discussed and conclusions were formulated. more...

Gas chromatography-mass spectrometry is a powerful tool to analyze flavor and fragrance from raw materials to the final commercial products. During the development of new technologies, most focuses have been given to novel columns, advanced detectors, and automation designs to leverage the instrument capabilities. The fundamental factors including polarity impact on sample homogenization and chemical interaction between analytes and extraction solvents are not equally emphasized during the sampling procedures. The current project focused on the liquid extraction procedures prior to GCMS analysis. Significant nucleophilic reactions were found to take place when a water-ethanol solvent was tried to extract flavor and fragrance ingredients. The isooctane in water-isooctane extraction system is friendly with GC columns and effective to extract the volatiles. However, the surfactants, humectants, and polymers in consumer cleaning products have significant impact on analyte distribution between water and isooctane solvents. The enhanced solubility of certain ingredients in water phase will change their profiling information in isooctane. During such extractions, hydrophilic volatile ingredients can be missed and the results become unreliable. For this reason, a newly designed water-n-propanol-isooctane extraction system was compared. This one-phase sample solution follows the homogenization rule in analytical chemistry and be more representative to the original samples. more...

Carbon–carbon double bond (CCDB) isomerization is a method for synthesizing new organic compounds from olefins and their derivatives, which was based on C=C migration along carbon chain and cis/trans transform, and it plays a vital role in the fields of organic synthesis, synthesis of daily chemicals, raw oil’s development and synthesis of natural products and so on. In this paper, advances of five types of catalytic methods for CCDB of olefins and their derivatives since the 1960s were discussed in detail; Based on his recent work, the author mainly introduces the application and development of photocatalysis in CCDB of olefins and their derivatives. more...

Ethanol production from agricultural products mainly corn, wheat, sweat potato and residue are gaining importance and requires an industrially viable novel technology namely simultaneous saccharification and fermentation process. This process has an advantage of carrying out saccharification using enzyme and fermentation using yeast in a single fermenter. The investment cost for industrial ethanol production using cheap agricultural residues can be well achieved using SSF process. The success of SSF process greatly depends upon the pretreatment methods using different enzymes to break the complex carbohydrates to simple sugars. Optimization of key process variables is essential to maximize the ethanol yield from suitable substrates. The key process variables affecting the SSF process are pH, temperature, fermentation time, enzyme concentration and substrate concentration. The medium components are to be screened for effective nitrogen, potassium and phosphorous sources to increase the ethanol yield. more...

With rapidly growing urbanization and industrialization in developing countries, a large volume of wastewater is produced from industries that contain chemicals generating high environmental risks, which could affect health and socio-economic activities if not treated properly. In this study, the discoloration of wastewater containing azo dyes by chemical oxidation process combined with a biological treatment was evaluated and applied on real textile wastewater generated from one Ethiopian industrial site. The use of TiO2 as a photocatalyst and the effect of the addition of H2O2 on color removal were investigated. Photocatalysis was followed by aerobic biological treatment and their combination resulted in 93.3 and 90.4% removal of color and chemical oxygen demand (COD), respectively. These results revealed that the combination of photocatalytic and biological treatment approach shows a promising potential for the removal of color from real textile wastewater. more...

The purpose of this study was to isolate the ethanolamine species of coconut phospholipid and to investigate their potency as drug delivery system by using it to encapsulate vitamin C. The study consisted of two stages: the first stage was isolation and characterization of coconut phosphatidylethanolamine species; and the second stage was utilization of coconut phosphatidylethanolamine liposomes to encapsulate vitamin C. A dark brown gel of coconut phosphatidylethanolamine species (CocoPEs) was isolated from dried coconut meat (9.3×10−3%, w/w). At least 15 species were found in coconut phosphatidylethanolamine. The fatty acyl chains of the species were capric, linoleic, oleic, stearic and arachidic acyl chains. At least four different phases were identified on CocoPEs i.e. planar-shape gel phase, rippling phase, liquid crystal phase and hexagonal phase. The temperature (Tp) was at 25.29°C for changing from planar-shaped gel to rippling phase, 32.62°C (Tm) for major transition from gel to liquid crystal, and 65.53°C (Th) from liquid crystal to hexagonal phase. All of CocoPEs liposomes encapsulation efficiency with cholesterol concentration up to 30% were above 80%. CocoPEs showed great potency as encapsulation material. It had high encapsulation efficiency and addition of cholesterol to the liposome membrane only slightly reduced the efficiency. more...

Dental enamel is the most complex and highly mineralized human body tissue, containing more than 95% of carbonated hydroxyapatite and less than 1% of organic matter. Current diagnostic methods for enamel caries detection are unable to detect incipient caries lesions. Many papers determine the re-mineralizing effect using many fluorinated compounds and different demineralizing solutions to test physical characterizations such as microhardness, roughness, wettability, among others, but there is not much information about the use of Raman Spectroscopy. Raman Spectroscopy is an efficient technique of chemical characterization to identify functional groups (phosphate-hydroxyl groups) found in the hydroxyapatite formula, which helps identify the level of mineralization on dental enamel surface. Raman spectroscopy is applicable to any state of aggregation of the material, indicated for biological samples. Given the minimum bandwidth of a laser source, as with all spectroscopic techniques that use a laser source, a small sample is sufficient, which makes it an important technique in the analysis of reactive products with very low yield. Raman spectroscopy can be used to obtain the main functional groups in order to determine the remineralization of dental enamel; these results are highly valuable as they can help us make the best decisions on dental treatments. more...

Cu-doped TiO2 (Cu/TiO2) film photocatalyst was prepared by combination of sol-gel and dip-coating process and pulse arc plasma method. The effect of Cu/TiO2 photocatalyst on CO2 reduction performance with reductants of H2O and H2 or NH3 was investigated. In addition, the overlapping two Cu/TiO2 coated on netlike glass discs were also investigated. The CO2 reduction performance of Cu/TiO2 film was tested under illumination of Xe lamp with or without ultraviolet (UV) light, respectively. As to the condition of CO2/H2/H2O, the best CO2 reduction performance has been achieved under the condition of CO2/H2/H2O = 1:0.5:0.5 with UV light illumination as well as without UV light illumination. The theoretical molar ratio of CO2/H2O or CO2/H2 to produce CO is 1:1. Since the molar ratio of CO2/H2/H2O = 1:0.5:0.5 can be regarded as the molar ratio of CO2/total reductants = 1:1, it is believed that the results of this study follow the reaction scheme of CO2/H2O and CO2/H2. On the other hand, as to the condition of CO2/NH3/H2O, the best CO2 reduction performance has been achieved under the condition of CO2/H2/H2O = 1:1:1 with UV light illumination as well as without UV light illumination. more...

Die-cast AZ91D magnesium alloy (8.9 wt.% Al, 0.6 wt.% Zn, 0.2 wt.% Mn, and balance Mg), as novel alternative biodegradable material, has received great attention due to their potential use in biomedical implants. However, their poor corrosion resistance in physiological fluids restricts practical applications. Cerium-based coatings have been studied as an environmental friendly option to enhance the corrosion resistance of magnesium alloys. In order to control the biodegradation rate of AZ91D magnesium alloy in simulated physiological solution, the formation of a coating from a solution containing cerium nitrate (Ce(NO3)3) was studied. The effect of different additives in the treatment solution (ascorbic acid, citric acid, and sodium citrate) on the anticorrosive properties of the coatings was evaluated. The characterization of the coatings was done using electrochemical techniques and SEM/EDS, XRD, and XPS analyses. The corrosion properties were examined in Ringer solution by polarization studies, open circuit measurements, and faradaic impedance spectroscopy. Results showed that the incorporation of additives improves the anticorrosive properties of the Ce-based film. The coating modified with ascorbic acid provides the best corrosion resistance. According to XPS results, the film is mainly composed by Mg oxides or hydroxides and Ce oxides. more...

Among the lead-free perovskite-structure materials, strontium titanate (SrTiO3—ST) and potassium tantalate (KTaO3—KT), pure or modified, are of particular importance. They are both quantum paraelectrics with high dielectric permittivity and low losses that can find application in tunable microwave devices due to a dependence of the permittivity on the electric field. Factors as Sr/Ti and K/Ta ratio in ST and KT ceramics, respectively, can alter the defect chemistry of these materials and affect the microstructure. Therefore, if properly understood, cation stoichiometry variation may be intentionally used to tailor the electrical response of electroceramics. The scientific and technological importance of the stoichiometry variation in ST and KT ceramics is reviewed and compared in this chapter. The differences in crystallographic phase assemblage, grain size, and dielectric properties are described in detail. Although sharing crystal chemical similarities, the effect of the stoichiometry is markedly different. Even if the variation of Sr/Ti and K/Ta ratios did not change the quantum-paraelectric nature of ST and KT, Sr excess impedes the grain growth and decreases the dielectric permittivity in ST ceramics, while K excess promotes the grain growth and increases the dielectric permittivity in KT ceramics. more...

The possibility of the formation of India perchlorate and mixed ligand complexes has been studied. It is assumed that during the extraction of indium in aqueous solutions of hydrochloric acid at various concentrations and constant ionic strength maintained by the addition of perchloric acid, indium is present in the organic phase in the form of ionic aggregates HClO4 · HInCl4. To study the hydration of Ions, the method of electrical conductivity was carried out in the “In(ClO4)3 - HClO4 - H2O” system. The structure of aqueous solutions of India perchlorates was determined by IR spectroscopy. The structures of trivalent perchlorate India have been established. more...

A concise review of the recent developments in some of the standard optical diagnostics applied for primary jet breakup studies has been presented here. Primary breakup is the core breakup of liquid jets and sheets into droplets upon its interaction with the ambient gaseous atmosphere. This phenomenon is encountered in various aerodynamic, fluid dynamic, and combustion situations. The imaging diagnostics reviewed here include photography, high-speed imaging, shadowgraphy, digital holography, ballistic imaging, jet core illumination, thermal imaging, Mie imaging, x-ray phase contrast imaging, and laser-induced fluorescence. The advantages and limitations of each technique, their success, and future developmental trend are discussed. more...

Biodiesel fuel (BDF) has gained much attention as a new sustainable energy alternative to petroleum-based fuels. BDF is produced by transesterification of vegetable oil or animal fats with methanol along with the co-production of glycerol. Indeed, transesterification of vegetable oil (136.5 g) with methanol (23.8 g) was performed under heating at 61°C for 2 h in the presence of NaOH (0.485 g) to produce methyl alkanoate (BDF) and glycerol in 83.7 and 73.3% yields, respectively. Although BDF was easily isolated by phase separation from the reaction mixture, glycerol and unreacted methanol remained as waste. In order to construct a clean BDF synthesis, the aqueous solution of glycerol and methanol was subjected to sacrificial H2 production over a Pt-loaded TiO2 catalyst under UV irradiation by high-pressure mercury lamp. H2 was produced in high yield. The combustion energy (ΔH) of the evolved H2 reached 100.7% of the total ΔH of glycerol and methanol. Thus, sacrificial agents such as glycerol and methanol with all of the carbon attached to oxygen atoms can continue to serve as an electron source until their sacrificial ability was exhausted. Sacrificial H2 production will provide a promising approach in the utilization of by-products derived from BDF synthesis. more...

This article will discuss natural dyes’ role, from colouring the cotton fabrics with some functionality to harvesting sunlight in the dye-sensitized solar cells. Natural dye colourants are identical to the low light- and wash-fastness. Therefore, an approach to improving the colourant’s physical properties is necessary. Colouring steps employing silica nanosol and chitosan will be presented. The first part will be these multifunctional natural dye coatings on cotton fabrics. Then, functionality such as hydrophobic surfaces natural dyed cotton fabrics will be discussed. Natural dyes are also potential for electronic application, such as solar cells. So, the second part will present natural dyes as the photosensitizers for solar cells. The dyes are adsorbed on a semiconductor oxide surface, such as TiO2 as the photoanode. Electrochemical study to explore natural dyes’ potential as sensitizer will be discussed, for example, natural dyes for Batik. Ideas in improving solar cell efficiency will be discussed by altering the photoanode’s morphology. The ideas to couple the natural dyes with an organic–inorganic hybrid of perovskite and carbon dots are then envisaged. more...

The structural, magnetic, electronic and elastic properties of A15 X3Ru (X = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) binary alloys are investigated using first-principles density functional theory (DFT) methods. Ru-based alloys have attracted remarkable research interest due to their unique properties, which make them suitable for high-temperature structural applications. In this chapter, the properties of several A15 Ru-based alloys are investigated in order to select the best suitable alloy/s for aerospace application. Heats of formation are calculated to determine the thermodynamic stability of the materials. Knowledge of the values of elastic constants is essential for understanding the mechanical properties of the materials. From our calculated elastic constants, the bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, melting temperature, anisotropic factor and the ratio B/G are determined. The electronic density of states are calculated and discussed. Lastly, the magnetic properties of A15 X3Ru alloys are studied. Thermodynamically stable Mn3Ru possesses high-magnetic moment compared to other X3Ru alloys, these results could pave way to experimental realization (synthesis) of Mn3Ru material. more...

Eurostat and the European Environmental Agency have in 2019 reported there is still need to continue implementing zero-carbon practices in European Union (EU) Countries although there has been a noted decrease of 22% in emissions when compared to their 1990 levels. This paper employed a system-Generalised Method of Moments (GMM) framework to evaluate the environmental impacts of tax systems in selected 28 EU economies from 2010 to 2017. The results of the study proved that aggregate environmental tax is not effectively lowering greenhouse gas emissions as expected, although it improves environmental sustainability. Possibly the environment tax revenue collected in the European Union countries was not used to enhance energy efficiency; hence it could not lower greenhouse gas emissions. The other findings demonstrate that when environmental tax is disaggregated (energy tax and transport tax) these instruments have been more efficient in lessening emissions and also improves environmental sustainability (in the case of transport tax). The paper, therefore, highlights the importance of adopting green tax instruments which are more focused and harmonising directly with environmental goals for EU economies. more...

The purpose of this chapter is to summarize potential applications of the high-power ultrasound technology (5 W/cm2; 20–100 kHz) in the food industry. Those applications are mainly related to the improvement in mass and energy transfer in different processes when ultrasound is applied in water or through air, e.g., reduction in dehydration; thawing and freezing times and energy costs of plant-, meat-, or fish-based products; increase the extraction yields of intracellular compounds with biological activity; reduction of chemical health risks such as cadmium or acrylamide; etc. The influence of some physical parameters like temperature and pressure in cavitation intensity and the potential of this technology to even inactivate microorganisms in food products and surfaces in contact with food will be discussed. Several examples of these applications will be presented, with reference to some of the industrial or pilot plant systems available in the market to be implemented in the food industry. more...

Chalcogenide thin films have attracted a great deal of attention for decades because of their unique properties. The recent developments on thin film-based supercapacitor applications were reported. As a result of sustained efforts, the experimental findings revealed remarkable properties with enhanced fabrication methods. The properties of perovskite solar cells were discussed in terms of crystal structure and phase transition, electronic structure, optical properties, and electrical properties. Perovskite solar cell has gained attention due to its high absorption coefficient with a sharp absorption edge, high photoluminescence quantum yield, long charge carrier diffusion lengths, large mobility, high defect tolerance, and low surface recombination velocity. The thin film-based gas sensors are used for equally the identification and quantification of gases, and hence should be both selective and sensitive to a required target gas in a mixture of gases. Metal chalcogenide materials are considered excellent absorber materials in photovoltaic cell applications. These materials exhibited excellent absorption coefficient and suitable band gap value to absorb the maximum number of photons from sun radiation. The photovoltaic parameters were strongly dependent on various experimental conditions. more...

Biogenic amines are low molecular weight organic nitrogen compounds. They are formed by the decarboxylation of amino acids or by amination and transamination of aldehydes and ketones during normal metabolic processes in living cells and therefore are ubiquitous in animals, plants, microorganisms, and humans. In food and beverages, they are formed by the enzymes of raw materials or are generated by microbial decarboxylation of amino acids. The structure of a biogenic amine can be aromatic and heterocyclic amines (histamine, tryptamine, tyramine, phenylethylamine, and serotonin); aliphatic di-, tri-, and polyamines (putrescine, cadaverine, spermine, spermidine, and agmatine); and aliphatic volatile amines (ethylamine, methylamine, isopentylamine, and ethanolamine). Many of them possess a strong pharmacologic effect, and others are important as precursors of hormones and components of coenzymes. The biogenic amine intoxication leads to toxicological risks and health hazards that trigger psychoactive, vasoactive, and hypertensive effects resulting from consumption of high amounts of biogenic amines in foods. The toxicological effects of biogenic amines increase when the mono- and diaminoxidase enzymes are deficient or drugs that inhibit these enzymes (pain reliever, stress, and depression drugs) are used. In this chapter, biosynthesis of biogenic amines, their toxic effects as well as their physiological functions, and their effect on health will be described. more...

Encapsulation, specifically microencapsulation is an old technology with increasing applications in pharmaceutical, agrochemical, environmental, food, and cosmetic spaces. In the past two decades, the advancements in the field of nanotechnology opened the door for applying the encapsulation technology at the nanoscale level. Nanoencapsulation is highly utilized in designing effective drug delivery systems (DDSs) due to the fact that delivery of the encapsulated therapeutic/diagnostic agents to various sites in the human body depends on the size of the nanoparticles. Compared to microencapsulation, nanoencapsulation has superior performance which can improve bioavailability, increase drug solubility, delay or control drug release and enhance active/passive targeting of bioactive agents to the sites of action. Encapsulation, either micro- or nanoencapsulation is employed for the conventional pharmaceuticals, biopharmaceuticals, biologics, or bioactive drugs from natural sources as well as for diagnostics such as biomarkers. The outcome of any encapsulation process depends on the technique employed and the encapsulating material. This chapter discusses in details (1) various physical, mechanical, thermal, chemical, and physicochemical encapsulation techniques, (2) types and classifications of natural polymers (polysaccharides, proteins, and lipids) as safer, biocompatible and biodegradable encapsulating materials, and (3) the recent advances in using lipids for therapeutic and diagnostic applications. Polysaccharides and proteins are covered in the second part of this chapter. more...

Distillation has been a very important separation technique used over many centuries. This technique is diverse and applicable in different fields and for different substances. Distillation is important in the desalination section. Various principles are used in desalting seawater and brackish water to fulfill the demands of freshwater. This work explains the modes and principles of distillation in desalination, their types, present improvement, challenges, and limitations as well as possible future improvements. The first and primary mode of distillation is the passive type. As times went by and the demand for freshwater kept increasing, other modes were introduced and these modes fall under the active distillation type. However, each mode has its own advantages, disadvantages, and limitations over each other. The principles and modes of distillation are as significant as understanding the energy sources needed for distillation. Hence, they are the basic knowledge needed for future innovation in the desalination industries. more...

Although sodium, potassium, calcium, and magnesium were isolated as the chemical elements by Sir Humphry Davy for the first time at the beginning of the 19th century, alkali salts and hydroxides have been widely known and used since the very ancient time. The word “alcali” & “alkali” was borrowed in the 14th century by literary Roman-Germanic languages from Arabic al-qalī, al-qâly ou al-qalawi (), which means “calcinated ashes” of saltwort plants. These ashes are characterized nowadays as mildly basic. They have been widely used in therapy, cosmetics, and pharmacy in Mediaeval Europe and the Middle East. However, the consumption of these alkali containing ashes, as well as natron salts and calcined lime-based materials used for different customer purposes, like therapy, pharmacy, cosmetics, glass making, textile treating, dyes, brick making, binding materials, etc., was commonly known since the very ancient times. The current review of the archeological, historical, and technological data provides the readers with the scope of the different everyday life applications of alkali and alkali-earth salts and hydroxides from ancient times till nowadays. The review obviously reveals that many modern chemical manufacturing processes using alkali and alkali-earth salts and hydroxides have a very ancient history. In contrast, there has been a similarity of targets for implementing alkali and alkali-earth salts and hydroxides in everyday life, from the ancient past till the modern period. These processes are ceramic and glass making, binding materials in construction, textile treatment, metallurgy, etc. So, this review approves the common statement: “The Past is a clue for the Future.” more...

The term lignin is derived from lignum, which means plant wood. Plant wood are mainly composed of extractives, hemicellulose, cellulose, and lignin. The lignin is a cross-linked polymer, made of three phenylpropanoid precursors, p-coumaryl, synapyl, and conniferyl alcohols. It is the most abundant polymer in plant world and act mechanically as a natural glue to bind hemicellulose and cellulose. Lignin is amorphous, soluble in alkali, condenses with phenol and has high melting temperature. The function of lignin is to protect the carbohydrates of the biomass from degradation, thus provide stability. The chapter includes information on types of lignin, structure, isolation, degradation, and transformation in to market value chemicals. The application of lignin and lignin base monomers for synthesis of plastic, hydrogels, adhesives, chemicals, fuels and other value added materials at industrial scale. more...

The long, stable operation of Jinshi and Tianqing programs proved the feasibility of Lurgi gasification by using Jincheng anthracite as raw material. Compared to other types of coal, Lurgi gasification by using Jincheng anthracite as raw material showed advantages including environmental protection, water consumption, effluent disposal, etc. By analyzing the characteristics of Lurgi gasification by using Jincheng anthracite as raw material, we discussed the choice of technical route and confirmed that the route of industrial gas, coal chemical products, and natural gas could exploit the advantage to the full. Finally, techno-economic evaluation of fuel gas prepared by Lurgi gasification with anthracite as raw material was discussed, and the result showed that industrial fuel gas produced by Lurgi gasification with anthracite as raw material could become an alternative to natural gas in industrial fuel gas field. more...

A redox catalyst can be present in the solution phase or immobilized on the electrode surface. When the catalyst is present in the solution phase the process can proceed via inner- (with bond formation, chemical catalysis) or outer-sphere mechanisms (without bond formation, redox catalysis). For the latter, log k is linearly proportional to the redox potential of the catalysts, E°. In contrast, for inner-sphere catalyst, the values of k are much higher than those predicted by the redox potential of the catalyst. The behaviour of these catalysts when they are confined on the electrode surface is completely different. They all seem to work as inner-sphere catalysts where a crucial step is the formation of a bond between the active site and the target molecule. Plots of (log i)E versus E° give linear or volcano correlations. What is interesting in these volcano correlations is that the falling region corresponding to strong adsorption of intermediates to the active sites is not necessarily attributed to a gradual surface occupation of active sites by intermediates (Langmuir isotherm) but rather to a gradual decrease in the amount of M(II) active sites which are transformed into M(III)OH inactive sites due to the applied potential. more...

Bottom sediment samples from six stations were sampled in pre monsoon 2016, from the Govindampalli – Durgarajupatnam (GP-DP) coast. Heavy metals viz., Fe, Mn, Cr, Cu, Ni, Pb, Zn and Cd analysis was carried out by using ICP-OES, and the average concentrations are as follows Fe > Mn > Zn > Cr > Pb > Ni > Cu > Cd. Various environmental indices like Factor Analysis (FA), Geo-accumulation Index (Igeo), Enrichment Factor (EF) and Pollution Load Index (PLI) were applied to the chemical data in order to know the levels of contamination and factors contributing to the pollution. Correlation coefficient results exhibits significant positive and negative relationships among Fe, Mn, Pb, Zn, Cd. All the environmental indices suggest that heavy metals were present at higher concentrations and the impacts of anthropogenic activities are crucial that serves as source of heavy metals in the zone. Relatively, maximum number of heavy metals viz., Fe, Ni and Pb were accumulated at the brackish environment i.e., at confluence of Swarnamukhi river (GP-S Station). more...

1998 onwards, a span reporting thousands of research articles describes the ever-increasing applicability of Schiff bases and their metallic complexes; this chapter comprehensively examines the literature of the last 20 years. The structural diversity of these molecules made them available for a very wide range of biological and abiological applications. Schiff bases are excellent chelators and due to this unique property have found their place in qualitative and quantitative determination of metals in aqueous media. The structural diversity of metal chelates proved these to be outstanding catalysts and displayed interesting fluorescence effect. Finally, Schiff base moieties have found a unique position during the in vitro and in vivo experiments for drug development against a huge number of biological entities including bacteria, fungi, cancer cells, viruses, parasites, etc. more...

GC-MS/MS method has been developed and validated for the determination and quantification of 35 multi-class pesticide residues in grape samples. Pesticides are selected from different families including organochlorines, organophosphorus, carbamates, pyrethroids, triazines, triazoles, pyrazoles, etc. The QuEChERS-dSPE (dispersive solid-phase extraction) method was used for the extraction of residues of pesticide. An extra cleanup step was included with the help of a primary secondary amine (PSA) and graphitized carbon black (GCB). Recoveries ranged from 70 to 100% with 14% relative standard deviation (RSD). Other parameters such as precision, recoveries, limit of detection (LOD), limit of quantification (LOQ), and linearity were also studied. Finally, the proposed analytical method was successfully employed for the determination of residues of pesticide in grape samples. more...

Volcanic ash-derived soils (VADSs) are of great importance in the agricultural economy of several emerging and developing countries. The surface-charge amphoteric characteristics will confer physical/chemical properties absolutely different to constant-charge soils. This surface reactivity will confer to them a particular behaviour in relation to the herbicide sorption, representing an environmental substrate that may become polluted over time due to intensive agronomic uses. Sorption is a key parameter to evaluate the fate and behaviour of herbicides in volcanic soils. Sorption type and kinetic sorption models are also necessary in order to develop and validate QSAR models to predict pesticide sorption on volcanic soils to prevent potential contamination of water resources. The use of solute sorption mechanism models and QSAR models for pesticide sorption in soils has contributed to a better understanding of the behaviour of pesticides on volcanic soils. This chapter is divided into five sections: Physical/chemical properties of volcanic ash-derived soils; Ionisable and non-ionisable herbicides’ fate and behaviour in soil; Kinetic sorption: mechanisms involved during sorption of ionisable and non-ionisable herbicides on VADS; Sorption of ionisable and non-ionisable herbicides on VADS; and Physical/chemical properties in QSAR models: a mechanistic interpretation. more...

Heavy metals (HMs) are natural environmental constituents, but their geochemical processes and biochemical equilibrium have been altered by indiscriminate use for human purposes. Due to their toxicity, persistence in the environment and bioaccumulative nature; HMs are well-known environmental contaminants. As result, there is excess release into natural resources such as soil and marine habitats of heavy metals such as cadmium, chromium, arsenic, mercury, lead, nickel, copper, zinc, etc. Their natural sources include the weathering of metal-bearing rocks and volcanic eruptions, while mining and other industrial and agricultural practices include anthropogenic sources. Prolonged exposure and increased accumulation of such heavy metals may have detrimental effects on human life and aquatic biota in terms of health. Finally, the environmental issue of public health concern is the pollution of marine and terrestrial environments with toxic heavy metals. Therefore, because of the rising degree of waste disposal from factories day by day, it is a great concern. Pollution of HMs is therefore a problem and the danger of this environment needs to be recognized. more...

Catalysts by virtue of lowering the activation barrier helps in the completion of a chemical reaction in a lesser amount of time without being themselves consumed. Utilizing the diverse non-covalent interactions in the design and construction of catalysts, recently anion-π interactions were also introduced, giving rise to an emerging field of anion-π catalysis. In the newly constructed anion-π catalysts, significant lowering of activation energy occurs by virtue of anion-π interactions. Till now, several important reactions generating chiral centers have been carried out on the π-acidic surfaces of anion-π catalysts, thereby revealing the significance of anion-π catalysis in the domain of asymmetric synthesis. The motive of this chapter is to highlight the role of anion-π catalysis in asymmetric synthesis and we surely believe that it will offer new opportunities in supramolecular chemistry. more...

Nowadays, electronic devices such as mobile phones and tablets are gadgets that have become common in most people’s daily lives. Although people often use tablets to read files, newspapers, or other papers, printing some documents is still necessary and convenient for most people. Therefore, a printer is one of the basic machines that many people use for work or to learn. Toner cartridges are the main components that print high-quality images or text on paper and are therefore of research value. Existing literature lacks research on performance of different printers and toners. Therefore, this study investigated and analyzed different types and brands of toners. In the study, toner cartridges provided by the four major suppliers were compared with data provided in material safety data sheets (MSDS) based primarily on different products. A comprehensive review and analysis of the concentration, function, definition, and impact involved in the product was conducted in this study. more...

Stable nitrogen and carbon isotopes were used to trace the interaction between atmospheric particles < 2.5 mm in diameter (PM2.5) with atmospheric physical variables and atmospheric chemical species in an urban environment. PM2.5 were collected daily at two sites in Mexico City during three dry seasons during two-week periods. PM2.5 varied between 10 and 70 μg/m3, with the highest concentrations occurring during low-speed southerly winds and the lowest during high-speed easterly winds. Stable carbon isotope composition (δ13C) showed that the main carbon source of PM2.5 included emissions from fossil fuel combustion, along with low-molecular-weight carbon emissions and suspended dust. Stable nitrogen isotope values (δ15N) in PM varied between −9.9 and 21.6‰. The most 15N-enriched particles generally occurred during low wind speeds and correlated significantly with hourly averaged ambient NOx and NO2 concentrations. Simultaneous samples from MER (commercial site) and XAL (industrial site) showed that PM2.5 mass concentration was generally lighter and the carbon and nitrogen isotopic compositions were heavier at the commercial site relative to the industrial site. The δ15N of PM2.5 increased with the %N in PM2.5concordant with an isotopic fractionation during gas-to-particle condensation. Results suggest that wind speed, along with the nitrogen emission source, determines the nitrogen isotopic composition of PM2.5. more...

The conversion of solar energy into chemical fuel is one of the “Holy Grails” of twenty-first century chemistry. Solar energy can be used to split water into oxygen and protons, which are then used to make hydrogen fuel. Nature is able to catalyze both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) required for the conversion of solar energy into chemical fuel through the employment of enzymes that are composed of inexpensive transition metals. Instead of using expensive catalysts such as platinum, cheaper alternatives (such as cobalt, iron, or nickel) would provide the opportunity to make solar energy competitive with fossil fuels. However, obtaining efficient catalysts based on earth-abundant materials is still a daunting task. In this chapter, we review the advancements made with zirconium phosphate (ZrP) as a support for earth-abundant transition metals for the OER. Our studies have found that ZrP is a suitable support for transition metals as it provides an accessible surface where the OER can occur. Further findings have also shown that exfoliation of ZrP increases the availability of sites where active species can be adsorbed and performance is improved with this strategy. more...