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Chromatographic Examinations in the Gas Network Odourised by Tetrahydrothiophene

Abstract

The paper presents the results of the spread of the tetrahydrothiophene (THT) - used as odourant - in the gas network. Such analyses allow quick detection of leaks in networks, systems and devices of gas supply directly to consumers. The main goal of the study was to determine the effectiveness of the use of portable chromatograph and comparing it with a stationary odourant concentration analyser. Based on these studies, an attempt to determine the odouration zone for the selected city have been also taken. For this purpose, three series of measurements were made - in each series 13 points were analysed. Obtained results confirmed the effectiveness of the measurement a concentration of odourant in the gas network using a portable gas chromatograph - difference in relation to the stationary chromatograph ranged from 1.91 to 2.55 %.

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Sorption of Synthetic Dyes Onto River Sediments: A Laboratory Study

Abstract

This work deals with sorption of cationic synthetic dye thioflavine T (ThT) onto the river sediment obtained from the Váh River under conditions of batch and column system using spectrophotometric methods. We found that sorption of ThT onto river sediment was a rapid process with reaching of concentration equilibrium within 2 h of interaction. The values of distribution coefficient (DC) defined as concentration ratio [ThT]sediment : [ThT]solution were linearly increased with increasing concentration of river sediment in solution within the range Csediment 1.25 - 10.0 g/dm3 and minimally changed in the range of initial pH values 2 - 6. The increasing concentration of ThT in model solution caused exponentially decrease in the value of DC. The sorption processes characterized by dependence between equilibrium specific sorption Qeq and ThT concentration Ceq in solution were better described by adsorption isotherm according to Freundlich (R2 = 0.979) than according to Langmuir adsorption isotherm (R2 = 0.914). From evaluation of ThT sorption onto river sediment in column system containing of 5 cm sediment layer with 30 cm of water column on the basis of ThT concentration changes in infiltrated water we found that these processes were significantly dependent on the rate of infiltrated water flow through the sediment layer Riw as well as on qualitative and quantitative composition of water. The highest ThT desorption from the sediment layer was found in seepage of 50 % (v/v) ethanol (EtOH) solution through the sediment and efficiency of ThT desorption decreased in the order: 50 % (v/v) EtOH > 0.1 mol/dm3 HCl > deionized water. Obtained data from the point of view of physico-chemical characteristics of the river sediment, such as pH, pHzpc (potentiometric titration), cation-exchange capacity (CEC) and elemental composition (X-ray fluorescence spectrometry), was also discussed

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Variation in Nutritional Properties of Mango (Mangifera indica) Juice Based on Varietal Difference and Thermal Holding Time

Abstract

This research demonstrated the significance of variety and thermal holding time (THT) at constant temperature (95 °C) on quality characteristics of mango juice. Eighteen samples from Mado, Julie and Kent mango varieties were produced using full factorial design. Quality parameters, sensory and microbial properties were determined. Variety and THT were significant for most notable variables considered except for some sensory properties. Juice of Julie had the highest vitamin C at 60s, while Mado were superior in virtually all other chemical parameters; having 31.93 – 49.97 µg/100g pro-vitamin A, 51.10 – 113 mg/100g total phenol, 25.60 – 81.40 mg/100g total flavonoid, 1.26 – 1.48 mg/L tannin and 12.60 – 13.60% °Brix. Microbial qualities were influenced by THT; with 60s long enough to achieve stable products. PCA cluster analysis further emphasized variety as the most quality-determining factor in mango juice.

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Removal Of Contaminants From Aqueous Solutions Using Hop (Humulus Lupulus L.) Agricultural By-Products

Abstract

Agricultural wastes can be used as an alternative to the existing sorbents for the removal of metals or synthetic dyes from contaminated liquids. In this work, the fine powdered biomass of the hop (Humulus lupulus L.) variety Osvald's clone 72 and variety Bohemie as a sorbent for the removal of Cd from aqueous solutions of CdCl2 spiked with radionuclide 109Cd and synthetic dyes thioflavine T (ThT) or methylene blue (MB) from single dye solutions under conditions of batch systems was used. The maximum sorption capacity Q = 264 µmol Cd/g (d.w.) was found in the case of the leaf biomass of hop (H. lupulus L.) variety Osvald's clone 72 at the initial concentration of CdCl2 10,000 µmol/dm3, whereby the sorption capacity decreased in the order Qleaves : Qstems : Qroots = 1.0 : 0.8 : 0.7. The sorbed amount of Cd was removed from the hop biomass with the following increasing desorption efficiency of the extraction reagents: deionised H2O << 0.1 mol/dm3 HCl ≤ 0.1 mol/dm3 EDTA-Na2. Similarly as in the case of Cd sorption, the kinetics of ThT and MB sorption by the leaf biomass of the hop (H. lupulus L.) variety Bohemie were also showed as two-phase processes. The maximum sorption of ThT approx. Q = 19 mg/g (d.w.) and MB approx. Q = 70 mg/g (d.w.) were found within the range of the initial values of pH 4 – 7. The sorption of both dyes by the leaf biomass from single dye solutions decreased with increasing biomass concentration and on the other hand increased with increasing the initial concentrations of ThT or MB. The process of ThT and MB sorption was better described by the Langmuir model than the Freundlich model of sorption isotherm. From the obtained values of Qmax, it was found that in the case of MB the dried leaf biomass showed more than 2-times higher sorption capacity (Qmax = 184 mg/g; d.w.) in comparison with the value predicted for ThT. Obtained results suggest that dried plant biomass of hop (H. lupulus L.) as agricultural by-products can be used as a potential sorbent for both types of studied contaminants.

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Thermal Stress of Surface of Mold Cavities and Parting Line of Silicone Molds

Abstract

The paper is focused on the study of thermal stress of surface of mold cavities and parting line of silicone molds after pouring. The silicone mold White SD - THT was thermally stressed by pouring of ZnAl4Cu3 zinc alloy with pouring cycle 20, 30 and 40 seconds. The most thermally stressed part of surface at each pouring cycle is gating system and mold cavities. It could be further concluded that linear increase of the pouring cycle time leads to the exponential increasing of the maximum temperature of mold surface after its cooling. The elongated pouring cycle increases the temperature accumulated on the surface of cavities and the ability of silicone mold to conduct the heat on its surface decreases, because the low thermal conductivity of silicone molds enables the conduction of larger amount of heat into ambient environment.

Open access
Suicidal overkill - three case reports

Abstract

All around the globe suicide is an increasing health problem because of the devastating effects that the loss of lives it leaves behind. There are instances when a suicide attempt is but a warning signal, a kind of cry for help, but in some cases its drastic character excludes any doubt about its annihilative aim. There are such situations in which the individuals opting for suicide try to limit the risk of failing in such act to the minimum.

This article presents three suicide cases autopsied at the Bistrita-Nasaud County Forensic Division tht share the fact that they use multiple, converging methods of self-destruction: the first case is that of an elderly man who, after ingesting a significant amount of thiocarbamide pesticides, hangs himself, the second case is that of a policeman in the rural area who, upon an acute alcohol intoxication, shoots himself six bullets in the stomach with the pistol provided, and the third case is of an unknown male citizen who, after sheltering under a bridge, drinks about 600 ml of petrol, then splashed himself with petrol and sets himself on fire.

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Effects of corn cob ash on lime stabilized lateritic soil

Soils: In, S. A. Ola, (ed.), Tropical Soils of Nigeria in Engineering Practice, (pp 61-84) A. A. Balkana / Rotterdam: Netherlands. [4] Bello, A. A., Ige, J. A. & Ayodele, H. (2015). Stabilization of Lateritic Soil with Cassava Reels Ash. British Journal of Applied Science and Technology 7 (6): 642-650, 2015, Article No: BJAST. 2015. 180, ISSN: 2231-0843 [5] Ogunribido, T.H.T. (2011). Potentials of Sugar Cane Straw Ash for Lateritic Soil Stabilization in Road Construction. International Journal of Science Emerging Technology . Vol. 3, No 5, May 2011

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Personalized Marketing in the Function of the Tourist Destination Improvement

REFERENCES [1] Anderson, C. (2012). The impact of social media on lodging performance. Cornell Hospitality Report (12), pp 4-12. [2] Brown, R. (2017). The Impact of Social Media on Travel Inspiration. Retrieved from http://www.olapic.com/resources/the-impact-of-social-media-on-travel-inspiration_blog-p1aw-f1tr-v1th-t1sm/ [3] ComScore, https://www.comscore.com/Insights/Press-Releases/2013/2/comScore-Releases-the-2013-U.S.-Digital-Future-in-Focus-Report?cs_edgescape_cc=US , 2013, accessed 2/3/2019 [4] Fotis, J., Buhalis, D., Rossides

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Morphometric variations of the Genus Barbonymus (Pisces, Cyprinidae) harvested from Aceh Waters, Indonesia

. 2015 – Genetic and morphological variation among hatchery stocks of Thai silver barb Barbonymus gonionotus (Bleeker, 1850) – Kasertsat J. Nat. Sci. 49: 856-867. Park I.S., Gil H.W., Oh J.S., Choi H.J., Kim C.H. 2015 – Comparative analysis of morphometric characteristics of Scorpaenidae and Gobioninae – Dev. Reprod. 19: 85-96. Schindler I., Schmidt J. 2006 – Review of mouthbrooding betta (Teleostei, Osphronemidae) from Thailand with description of two new species – Z. Fischkunde 8: 47-69. Thinh D.V., Van N.S., Nguyen T.H.T. 2012 – Barbonymus

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Post-Dependence Discourse in the Language of Politicians of Prawo I Sprawiedliwość and Platforma Obywatelska

. (2014), Unijna pasywność, amerykańska sprawność, Do Rzeczy, nr 19/067. MALISZEWSKI N. (2015), Sondaż: Polacy nie chcą przyjmować uchodźców , [online: 20 August, 2016], http://wiadomosci.onet.pl/kraj/sondaz-polacy-nie-chca-przyjmowac-uchodzcow/q8tht5 . NYCZ R. red. (2011), Kultura po przejściach, osoby z przeszłością. Polski dyskurs postzależnościowy – konteksty i perspektywy poznawcze , Kraków. OLECHOWSKI K. (2014), Postzależnościowy wymiar dyskursu medialnego na przykładzie publicystyki „Gazety Wyborczej” i „Rzeczpospolitej” , Komunikacja

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