Practical scale evaluation of a photocatalytic air purifier equipped with a Titania-zeolite composite bead filter for VOC removal and viral inactivation

SummaryIn May 1990, 218 patients with haemophilia A regularly attending the Leuven Haemophilia Center were randomly assigned to a group receiving either of two newly introduced factor VIII concentrates: factor VIII-P, an intermediate purity pasteurized concentrate, or factor VIII-SD, a high purity concentrate treated with solvent-detergent for viral inactivation.Patients were followed from May 1990 until October 1991. Between August 1991 and October 1991 a clinically important factor VIII inhibitor was detected in five out of the 109 patients receiving factor VIII-P while none of the 109 patients receiving factor VIII-SD developed such antibodies. All patients acquiring an inhibitor had previously been clinically tolerant to transfused factor VIII with 200 to more than 1,000 days of exposure to factor VIII prior to May 1990. Patients with inhibitors were transfused daily with 30 U factor VIII-SD per kg body weight, which was associated with a gradual decline of the inhibitor level. In all patients the antibodies were relatively slow-acting and predominantly directed towards the light chain of factor VIII.This study demonstrates a higher than expected incidence of factor VIII inhibitors associated with the use of a specific factor VIII concentrate in multitransfused haemophilia A patients. It indicates the usefulness of evaluating newly introduced concentrates in prospective, randomized trials.

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APPLICATION OF TITANIUM OXIDE COATINGS FOR NEUTRALIZATION OF HAZARDOUS CHEMICAL SUBSTANCES

Collection of scientific works of Odesa Military Academy ◽

10.37129/2313-7509.2019.12.2.131-136 ◽

2019 ◽

Vol 2 (12) ◽

pp. 131-136

Author(s):

О. Halak ◽

N. Poltorak ◽

О. Kravchuk ◽

V. Synko ◽

Y. Korol

Keyword(s):

Ultraviolet Rays ◽

Gaseous Emissions ◽

Oxide Coatings ◽

Mobile Objects ◽

Hazardous Chemical ◽

Catalytic Material ◽

Air Purifier ◽

Domestic Use ◽

Purification Methods ◽

Plasma Electrolytic

Contamination of hazardous chemicals is currently considered one of the major environmental problems. The methods of purification of gaseous emissions depending on the physicochemical properties of pollutants, in particular dangerous chemical, their aggregate state, concentration in the gas environment are studied in this article. The effect of aerosol content such as dust and soot is analyzed as well as the efficiency of purification methods at different temperature intervals, methods of purification of multicomponent mixtures. The comparative characteristics of thermochemical, reagent, sorption and catalytic methods are given and the prospects of their application in filtering systems of stationary and mobile objects are evaluated. It has been proved that almost any organic compounds can be oxidized (mineralized) on the TiO2surface. In practice, any photocatalytic air purifier includes a porous TiO2 deposited carrier, which is irradiated with ultraviolet rays and through which air is purged. Photocatalysis is suitable for domestic use as it can occur at room temperature. For example, a thermocatalytic method of destroying harmful substances requires preheating the air to a temperature above 200 ° C. Photocatalysis destroys substances that penetrate even through activated carbon filters. Features of formation of oxide coatings by plasma-electrolytic oxidation of titanium alloys are considered. It is proposed to refine the design of collective defense systems on armored vehicles and stationary facilities with additional installation in the filter-absorber of the grid with the deposited layer of catalytic material, which will neutralize various types of dangerous chemicals due to photocatalytic air purification.

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A Study on the Influence of PUI and Interaction of Home Air Purifier on Brand Preference and Purchase Intention.

Journal of Industrial Design Studies ◽

10.37254/ids.2019.09.49.05.41 ◽

2019 ◽

Vol 49 ◽

pp. 41-54

Author(s):

Juhee Lee ◽

Sukgill Jung

Keyword(s):

Purchase Intention ◽

Brand Preference ◽

Air Purifier

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A rapid small scale evaluation of ultrafiltration performance for surface water treatment at Alcantarilha's water treatment works (Algarve, Portugal)

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0109 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 199-206

Author(s):

M. Ribau Teixeira ◽

H. Lucas ◽

M.J. Rosa

Keyword(s):

Water Treatment ◽

Membrane Fouling ◽

Conventional Treatment ◽

Apparent Molecular Weight ◽

Small Scale ◽

Hydraulic Permeability ◽

Scale Evaluation ◽

Surface Water Treatment ◽

Drinking Water Production ◽

Pre Treatment

A rapid small-scale evaluation of ultrafiltration (UF) performance with and without physical–chemical pre-treatment was performed to up-grade the conventional treatment used for drinking water production in Alcantarilha's water treatment works, Algarve, Portugal. Direct UF and pre-ozonation/coagulation/flocculation/sedimentation/UF (O/C/F/S/UF) were evaluated using polysulphone membranes of different apparent molecular weight cut-off (MWCO) (15–47 kDa). The results indicated that (i) UF is an effective barrier against microorganisms, including virus larger than 80 nm; (ii) for surface waters with low to moderate SUVA values, direct UF performance is equivalent or better than the conventional treatment in terms of residual turbidity, while UV254 nm and TOC residuals require the use of O/C/F/S/UF; (iii) the permeate quality improves with the membrane apparent MWCO decrease, especially for the direct UF, although the conventional treatment performance is never reached using UF; (iv) membrane fouling and adsorption phenomena are more severe in direct UF than in O/C/F/S/UF sequence (pre-ozonation decreases the membrane foulants by decreasing their hydrophobicity) and these phenomena increase with the membrane hydraulic permeability and, particularly, with the membrane apparent MWCO.

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Behaviour of Coli Phages in Oxidation Ponds

Water Science & Technology ◽

10.2166/wst.1985.0113 ◽

1985 ◽

Vol 17 (10) ◽

pp. 219-227 ◽

Cited By ~ 9

Author(s):

T. Omura ◽

H. K. Shin ◽

A. Ketratanakul

Keyword(s):

Laboratory Experiments ◽

Field Investigation ◽

Host Cells ◽

Coliform Bacteria ◽

Alkaline Ph ◽

Viral Inactivation ◽

Effects Of Temperature ◽

Oxidation Ponds ◽

Incubation Temperatures ◽

Inactivation Efficiency

Coliphages are among the most promising indicators of viral inactivation efficiency of wastewater treatment. Therefore, it is important to investigate the behaviour of coliphages in oxidation ponds from the viewpoint of predicting the inactivation of infectious viruses. In this study, numbers of coliphages were measured in oxidation ponds consisting of a series of facultative and maturation ponds. In parallel with this investigation, the effects of temperature and pH on the behaviour of coliphages were examined in the laboratory, employing three species of coliform bacteria as host cells. The field investigation showed that there was positive correlation between counts of coliphages and those of coliform bacteria, and that more than 99% of coliphages were inactivated. The inactivation efficiency of coliphages in the facultative pond was much higher than in the maturation pond. The results of the laboratory experiments indicated that at 30°C more than 99% of the coliform group were destroyed in 7 days of incubation and that coliphages counts increased from 105/100 ml to 107/100 ml with a lag time of 3 days. Greater reduction of the coliform count was obtained at higher incubation temperatures. It was observed that the coliphages possessed greater ability to attack coliform bacteria at acidic rather than alkaline pH.

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Viral inactivation by potassium ferrate

Water Science & Technology ◽

10.2166/wst.1995.0591 ◽

1995 ◽

Vol 31 (5-6) ◽

pp. 165-168 ◽

Cited By ~ 10

Author(s):

Futaba Kazama

Keyword(s):

Phosphate Buffer ◽

Potassium Ferrate ◽

Sodium Thiosulphate ◽

Viral Inactivation ◽

Complete Decomposition ◽

Kinetics Of ◽

Oxidative Intermediate

The kinetics of inactivation by potassium ferrate were studied using a bacteriophage, F-specific RNA-coliphage Qβ as a viral model. The inactivation appeared to be expressed by Hom's model in phosphate buffer at pH 6, 7, and 8. The rate of inactivation depended on pH; the lower pH, the faster inactivation observed. To consider the mechanism by which ferrate caused inactivation, the efficiency of inactivation was checked after ferrate decomposition in buffer. Effective inactivation following Hom's model was also observed after the complete decomposition of ferrate ion; however, the efficiency of that inactivation disappeared by the addition of sodium thiosulphate, suggesting that rather long-lived oxidative intermediate was generated by the decomposition of ferrate ion. The intermediate might take part in the inactivation.

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