Growth Rate and Morphology of a Single Calcium Carbonate Crystal on Polysulfone Film Measured with Time Lapse Raman Micro Spectroscopy

The phenomenon of calcium carbonate crystal growth from aqueous solutions on surfaces widely occurs in systems where carbonate and bicarbonate ions are present, such as in domestic systems, waste and drinkable water treatment systems or industrial apparatus where water is used.

Crystal growth leads to the formation of mineral scale which reduces the performance of membrane materials in equipment. The scale development is affected by factors such as: pH, super-saturation index, temperature, water composition etc.

The process of scaling and crystal growth includes the following stages:The induction period involve nucleation and crystal growth, and The mineralizing crystals and others particles transportation from the bulk and its adhesion to the surface,and Ageing of crystals at a surface, for instance due to recrystallization and dehydration.Other components present in a mineralizing solution could increase or decrease the crystal growth rate by adhesion to crystal surfaces.

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Mixed Matrix Membranes for Adsorption Application

Mixed matrix membrane (MMM), a currently popular research field, is a type of membrane formed by incorporating fillers in polymer matrix. Its preparation procedures mainly involve with only blending and phase inversion.

According to its structure, MMM can typically be divided into two categories. The first one is with a dense structure, mostly developed for the applications in gas separation, pervaporation, fuel cell, and so on. The fillers employed for improving the MMM performance in this category are usually inorganic nanomaterials (zeolite, carbon nanotube, metal organic framework, etc.) with specific features (shape, pore size, surface interaction, etc.).

The other category is with a porous structure, specially designed for adsorption purpose. Micro-to-nano-size particles with functionality are regularly adopted as the fillers for this kind of MMM to provide the adsorptivity with target solutes.

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Arrested Precipitation Technique for Synthesis of Chalcogenide and Oxide Thin Films

Interest in the use of photo electrochemical solar cells for low cost energy conversion has led to an extensive research in the search for novel and suitable thin film semiconductor materials. The techniques presently used for synthesis of mixed metal chalcogenide and oxide thin films are CBD, MOCVD, spin coating, electro deposition, spray pyrolysis, sputtering, crystal growth, and chemical bath deposition.

All these deposition techniques require specific sophisticated instrumentation. In this regard APT is more attractive and relatively inexpensive presently used by us for deposition of mixed metal chalcogenide and oxide thin thin films.

In the present investigation we attempt to prepare mixed metal chalcogenide and oxide thin films by arrested precipitation technique. The purpose of work is to establish and optimize the growth condition to produce these thin films.

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Boron Isotope Fractionation in Bell Pepper

Stable isotope systems of major nutrients like oxygen or carbon have been successfully used to trace the provenance of plants and food products. The boron  isotope system is of great interest in plants because B was found to be an essential micronutrient in plants occurring predominantly in the cell walls and acts as a strengthening component.

Boron has two stable isotopes, 11B (~80% abundance) and 10B (~20% abundance) and its isotope amount ratio n(11B)/n(10B) is reported as delta (δ)-values (eqn. 1), referring to the Standard Reference Material (SRM®) 951 from the National Institute for Standards and Technology (NIST; Gaithersburg, USA).

In aqueous solutions, B exists as uncharged trigonal boric acid B(OH)3 in acidic media or as tetrahedral borate ion B(OH)4 - in alkaline media. The lower vibrational energy of the trigonal coordinated boric acid species causes a preferential incorporation of the heavier B isotope compared to the tetrahedral species  leading to boron isotope fractionation in nature.

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Isotopic Abundance Analysis of Biofield Treated Benzene, Toluene and p-Xylene Using Gas Chromatography-Mass Spectrometry

Benzene, toluene and p-xylene isomers are nonpolar organic liquid, volatile, aromatic and the most important constituents of gasoline. Benzene, toluene and p-xylene are one of the important sources of energy being utilized with petrol/gasoline for vehicle fuel.

All three compounds are produced during the process of making gasoline and other fuels from crude oil as well as in making coke from coal. Benzene have been used for long time in manufacturing plastics, detergents, pesticides, and other chemicals such as ethyl benzene, cyclohexane, nitrobenzene, chlorobenzenes and maleic anhydride.

Toluene has numerous commercial and industrial applications and was used as a solvent in paints, lacquers, thinners, glues, correction fluid, nail polish remover, and in printing and leather tanning processes. p-xylene has been used in adhesives industry, paint industry, and as manufacturing solvent in rubber industries.

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Biogeochemical Cycling of Nutrients and Thermodynamic Aspects

The term “biogeochemical cycles” is used in order to describe the transfer and transformation of matter and energy between the biosphere and the other active reservoirs of Earth namely the atmosphere, hydrosphere, and lithosphere.

During the functioning of a biogeochemical cycle, a series of molecular species which are essential for supporting life on the planet, also referred to as nutrients, are being constantly transported and chemically transformed. The main chemical elements making up the basic nutrients circulating within a specific biogeochemical cycle and which are involved in the structuring of complex bio-polymers (e.g. proteins, DNA, RNA, etc.) are C, N, S, P, and O.

A biogeochemical cycle is activated via coupling of the biosphere to nutrient fluxes supplied by specific sites or active centers on Earth (e.g. volcanoes and hydrothermal fields). Such sites/centers act as a constant source of matter (e.g. volatile chemical species) and/ or energy on the Earth surface, either on a regional or a global scale, which can be used by different living forms.

Prevention of Dust Hazards Affecting Workers in Hard Coal Mines

Prevention of dust hazards  and inhalation exposure of the mining personnel to chemical agents  are important issues influencing optimisation of OHS conditions at mining facilities. Increased coal extraction results in higher dust immissions at a workplace, posing an explosion hazard and leading to development of lung diseases in mining personnel due to the presence of free silica in coal dust.

The new air and water sprinkling solutions implemented in the mining industry  reduce substantially airborne dust pollution in mines.

However, water sprinkling systems commonly used at mining facilities are not effective enough in reducing dust immissions. Air dampeners are used to further improve OSH conditions as regards dust concentrations.

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