Examining the Effect of Freezing Temperatures on the Survival Rate of Micro-Encapsulated Probiotic LA5 Using the Flash Freeze-Drying (FFD) Strategy.

This work proposes a novel drying method suitable for probiotic bacteria, called flash freeze-drying (FFD), which consists of a cyclic variation in pressure (up-down) in a very short time and is applied during primary drying. The effects of three FFD temperatures (-25 °C, -15 °C, and -3 °C) on the bacterial survival and water activity of LA5 (LA), previously microencapsulated with calcium alginate and chitosan, were evaluated. The total process time was 900 min, which is 68.

Changes in solution turbidity and color during paracetamol removal in laboratory and pilot-scale semicontinuous ozonation reactors.

Injecting ozone by means of a venturi device causes an increase in the mass transfer coefficient with respect to gas dissolution through a microdiffuser. Moreover, it was observed that significant turbidity levels are not formed (<1 NTU) when using a microdiffuser, probably due to the relatively high stirring which avoids formation of intermolecular hydrogen bonds. On the contrary, employing a venturi injector led to the production of high turbidity levels in water (up to 20 NTU).

Removal of Aniline and Benzothiazole Wastewaters Using an Efficient MnO/GAC Catalyst in a Photocatalytic Fluidised Bed Reactor.

This work presents an efficient method for treating industrial wastewater containing aniline and benzothiazole, which are refractory to conventional treatments. A combination of heterogeneous photocatalysis operating in a fluidised bed reactor is studied in order to increase mass transfer and reduce reaction times. This process uses a manganese dioxide catalyst supported on granular activated carbon with environmentally friendly characteristics.

Exploring the Decomposition Products of 1,3,3,3-Tetrafluoropropene and Perfluoro-(3-methylbutan-2-one) Gas Mixtures in Medium-Voltage Electrical Switchgear as Alternatives to SF6.

In this work, binary and ternary gas mixtures of 1,3,3,3-tetrafluoropropene, HFO-1234ze(E), and perfluoro-(3-methylbutan-2-one), CFC()CF(CF), with CO and synthetic air, are presented as alternatives to SF6 in medium-voltage electrical equipment. They were used in four medium-voltage switchgear cubicles replacing SF6 gas, and after a period of time, under permanent 30 kV AC voltage, gas mixture samples were extracted and analyzed on the same day using a validated methodology based on gas chromatography (GC) coupled to mass spectrometry (MS) and thermal conductivity (TCD). CF (tetrafluoromethane), CF (hexafluoroethane), CF (hexafluoropropylene), CHF7 (1,1,1,2,2,3,3-heptafluoropropane), CHF (difluoromethane), and the cis and trans-CHF (1,3,3,3-tetrafluoropropene) have been identified as decomposition products in these gas mixtures.

Kinetic modelling for concentration and toxicity changes during the oxidation of 4-chlorophenol by UV/HO.

This work develops a kinetic model that allow to predict the water toxicity and the main degradation products concentration of aqueous solutions containing 4-chlorophenol oxidised by UV/HO. The kinetic model was developed grouping degradation products of similar toxicological nature: aromatics (hydroquinone, benzoquinone, 4-chlorocatechol and catechol), aliphatics (succinic, fumaric, maleic and malonic acids) and mineralised compounds (oxalic, acetic and formic acids). The degradation of each group versus time was described as a mathematical function of the rate constant of a second-order reaction involving the hydroxyl radical, the quantum yield of lump, the concentration of the hydroxyl radicals and the intensity of the emitted UV radiation.