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In this paper we present a new vibrational configuration interaction method known as a parallel vibrational multiple window configuration interaction P_VMWCI which generates several VCI matrices and enables the variational treatment of medium size molecular systems. Application to acetaldehyde gives a new interpretation of the MIR experimental data. [ABSTRACT FROM AUTHOR]

Integration of information technology in education more rapidly performed in a medium of learning. Threedimensional (3D) molecular modeling was performed in Augmented Reality as a tangible manifestation of increasingly modern technology utilization. Based on augmented reality, three-dimensional virtual object is projected in real time and the exact environment. This paper reviewed the uses of chemical learning supplement book of aldehydes and ketones which are equipped with three-dimensional molecular modeling by which students can inspect molecules from various viewpoints. To plays the 3D illustration printed on the book, smartphones with the open-source software of the technology based integrated Augmented Reality can be used. The aims of this research were to develop the monograph of aldehydes and ketones with 3 dimensional (3D) illustrations, to determine the specification of the monograph, and to determine the quality of the monograph. The quality of the monograph is evaluated by experiencing chemistry teachers on the five aspects of contents/materials, presentations, language and images, graphs, and software engineering, resulted in the result that the book has a very good quality to be used as a chemistry learning supplement book. [ABSTRACT FROM AUTHOR]

People dissipate most time in distinct indoor areas while their fitness is exposed to different varieties of air pollutants. Volatile Organic Compounds (VOCs) encompass several chemical compounds that pollute the indoor surroundings. They are to be had withinside the constructing particularly from internal sources which includes flooring, timber products, constructing materials, adhesives and different consumables. Indoor air is observed for their consequences on fitness of human being like carcinogenic and mutagenic. Current studies identify sources of VOCs and their effects. The maximum regularly monitored indoor natural pollution for epidemics and health dangers are benzene, ethylbenzene, xylene, toluene, terpenes and aldehydes (formaldehyde, benzaldehyde). In indoor environments, their concentrations rely on factors which include the traits of the emission sources, the microclimate and the aeration. Concentrations of formaldehyde and toluene extended drastically with rising temperature. Benzene enters the inner surroundings of the constructing from outside, particularly from visitors and commercial sites. Formaldehyde, alpha pinene and limonene are acquired from inner sources as a part of furniture, household appliances and building materials. [ABSTRACT FROM AUTHOR]

A variety of novel types of pyrazole, isoxazole and cyclohexadienone were synthesized from Curcumin. Curcumin was prepared via Claisen-Schmidt Condensation between various aldehydes and acetyl acetone. Then Curcumin was reacted with phenyl hydrazine, hydrazine hydrate, guandine.HCl, hydroxyl amine.HCl, acetyl acetone and ethylacetoacetate to produce of pyrazole, isoxazole and cyclohexadienone derivatives. [ABSTRACT FROM AUTHOR]

The transformation of alcohols to aldehydes or ketones is one of the most essential reactions in organic synthesis. An interesting alternative to aerobic conditions to produce oxygenated products, such as aldehydes and ketones, can be the dehydrogenation of alcohols under anaerobic conditions with the utilization of unsaturated organic molecules as hydrogen acceptors, instead of molecular oxygen. In this case, the oxidative dehydrogenation is changed to transfer dehydrogenation, which overcomes the safety limitations of aerobic oxidation. The influence of varying the stabilizer type (PVA, PVP, and THPC) during the synthesis of palladium nanoparticles via sol-immobilization technique on the resulted particles, and their catalytic activity on the liquid phase transfer dehydrogenation of 1-phenylethanol (1-PhEt) has been investigated for the first time. The chemical composition and morphology of the fresh and used catalysts were determined using XRD, XPS, BET, SEM-EDX, and TEM. By evaluating the catalytic activity of the series of 1% Pd/TiO2 catalysts prepared using different PVA/Pd weight ratio, the results illustrate that two main parameters can mainly control the catalytic activity of 1% Pd/TiO2 in the liquid phase transfer dehydrogenation of 1-PhEt, these are Pd(0)/Pd(II) ratio and the particle size of the catalyst. The results show that two different regimes can be identified during the liquid phase transfer dehydrogenation of 1-PhEt. At the initial time, the particle size parameter appears to control the catalytic performance of 1-PhEt while the effect of Pd oxidation state starts to take place after reaching iso-conversion, where the percentage of Pd(0)/Pd(II) increases while the reaction proceeds. [ABSTRACT FROM AUTHOR]

Variously substituted aliphatic and aromatic aldehydes are oxidized catalytically (Tungstosilicic Acid) into the corresponding acids using aerial oxygen at room temperature under solvent free conditions in good to high yields. Different reaction conditions such as reaction temperature, solvents, catalyst in varying quantities are studied to get the optimized reaction condition. The utilization of room temperature, solvent free conditions, aerial oxygen, simple work up, environmentally benign methodology make this reaction green from the economic and environmental point of view. The present method is operationally simple compared to all exiting methods and can benefit both academic and industrial processes. The products have been characterized by IR, 1H-NMR, 13C-NMR spectroscopy. [ABSTRACT FROM AUTHOR]

In the present investigation2-(hydrazinylmethyl)-1,3-benzothiazole was reacted with aryl aldehyde to give 2-{[2Z)-2-arylhydrazinyl]methyl}-1,3-benzothiazole (3a-f), which in absolute ethanol treated with thioglycolic acid (0.001 mol) and anhydrous zinc chloride under reflux for 8 hr to get 3-[1,3-benzothiazol-2-ylmethyl) amino]-5(aryl)-1,3-thiazolidin-2-ones (4a-f). On the other hand [Benzothiozole N-aryl thiozolemethanamines] (5a-f) wereobtained,when the compounds (3a-f), are treated with diazomethane. [ABSTRACT FROM AUTHOR]

This work aims at determining the optimized parameter to prepare cinnamaldehyde nanoemulsion by using high pressure homogenizer (2 passes at 900 bar) and ultra turrax T25 (12000 rpm for 5 min). Thirteen formulation of cinnamaldehyde nanoemulsion obtained by Design Expert software were prepared at a range of oil and surfactant concentration between of 5% and 10% (v/v). Commercial cinnamaldehyde was blended with deionized water and Tween 80 (emulsifier). The responses used in obtaining the optimized condition were droplet size, polydispersity index (PDI) and emulsion stability (ξ-potential). Result showed that nanoemulsion prepared using 5% (v/v) cinnamaldehyde and 5% (v/v) Tween 80 and homogenized using high pressure homogenizer (APV, Germany) has the smallest size of droplet. The response surface plots for droplet size showed that droplet size (diameter, nm) decreased as the concentration of cinnamaldehyde oil and Tween 80 decreased. However ξ-potential value (mV) showed an increment as the cinnamaldehyde oil concentration decreased and Tween 80 increased. The optimum formulation as predicted by response surface methodology in order to produce a stable cinnamaldehyde nanoemulsion was at 5% cinnamaldehyde oil and 7.11% Tween 80. At this optimized conditions the droplet size and ξ-potential values were 56.56 nm and -4.32 mV, respectively. [ABSTRACT FROM AUTHOR]

The article discusses the efforts of textile and chemical manufacturers to develop innovative products which reduce the overall exposure to harmful substances, with emphasis on the aldehyde scavenger from NICCA USA Inc.

Pollution with aldehydes of water courses is less and inconclusive studied today. However, current researches don't establish limits of some quality parameters that can be admitted into surface water by point of view of these contamination resources. Having this objective is given possibilities to emphasis the emission of aldehydes in the environment Accordingly to an experimental program for its identification and assessment, present the effective techniques of sampling and analysis. Chemical Plant, the biggest chemical complex in Romania operates a prominent Oxo-Alcohol production in Chemical Plant and causes significant emissions of aldehydes and the relevant imissions into the river Olt. It has been used a new diffusion gadget as against the process based on the adsorption principle in the liquid, used so far, but which is rather complicated and extremely sensitive to other substances. So far there are no directives to regulate air pollution or surface water of aldehydes. There are parameters according to which the aldehydes are a potential risk on health, which has imposed by this study, group of substances analysis, knowing that by production of Oxo -- Alcohol is formed a considerable amount of aldehydes. The detection limit for the aldehydes has been located around the value of 40 mg / l. Measurements have been effectuated both in braking off and working period of the Oxo - Alcohol outfit from Chemical Plant, by comparing the results of the new sampling system with diffusion separator built and with existing measurement process. Experimental research results are evaluated and established the solutions from the reduction of the pollution. [ABSTRACT FROM AUTHOR]

In this work we describe a rapid method for analysis of volatile profiles of several commercial fruit juices using GC/MS instrument after liquid-liquid extraction. Volatile flavor compounds have been identified based on mass spectrum obtained in EI mode. This method allows to analyses a wide range of flavor compounds (esters, aldehydes, alcohols, terpenoids) the procedure was rapid, simple and inexpensive. Moreover, by means of volatile compounds it could be possible to distinguish between juices of organic and conventional production and those with flavorings addition. More of 20 compounds were identified and quantified as relative chromatogram area taken on larges ion in mass spectrum. [ABSTRACT FROM AUTHOR]

Glucose, as a model compound of cellulosic biomass, was used as a test material. Ca(OH)2 and NaOH were selected as alkali. Results showed that both NaOH and Ca(OH)2, can promote the formation of lactic acid in a hydrothermal reaction of glucose. In the case of the addition of NaOH, lactic acid was obtained with a good yield of 27% based on a carbon base at 300 °C for 60 s with a NaOH concentration of 2.5 M. In the case of the addition of Ca(OH)2, the highest yield of lactic acid is 20%, which occurred at 300 °C for 60 s with a Ca(OH)2 concentration of 0.32 M. The formation mechanisms of lactic acid from glucose were also discussed according to intermediate products identified. Lactic acid may be generated via formaldehyde, glycolaldehyde besides via the aldose having three carbon atoms in hydrothermal reaction which all formed by the reverse aldol condensation of hexoses. [ABSTRACT FROM AUTHOR]

Genes of interest can be selectively metallized via the incorporation of modified triphosphates. These triphosphates bear functions that can be further derivatised with aldehyde groups via the use of click chemistry. Treatment of the aldehyde-labeled gene mixture with the Tollens reagent, followed by a development process results in the selective metallization of the gene of interest in the presence of natural DNA strands. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]