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Abstract

The goal of this study was to clarify the effect of alkaline pretreatments on the thermal decomposition and composition of industrial hemp (Cannabis sativa L.) samples. Thermogravimetric/mass spectrometric measurements (TG/MS) have been performed, on untreated, hot water washed, and alkali-treated hemp samples. The main differences between the thermal decomposition of the samples are interpreted in terms of the different alkali ion contents which have been determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES) method. Principal component analysis (PCA) has been used to find statistical correlations between the data. Correlations have been obtained between the parameters of the thermal decomposition and the alkali ion content as well as the altered chemical structure of the samples. The differences in the thermal behavior of the samples are explained by the different K+ and Na+ contents and the changed structure of the hemicellulose component of the samples due to the pretreatments. The more alkali ions remain in the hemp samples after the alkali treatment, the more ash, char and lower molecular products are formed during thermal decomposition.

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Between 49 and 70 days of age, three groups of growing pigs (n = 10 each) were fed diets containing 0, 0.3 and 0.5 mg/kg T-2 toxin, respectively, for 21 days. The feed of another two groups of pigs (n = 10 each) contained 0.3 or 0.5 mg/kg T-2 toxin, respectively, plus a feed additive developed for splitting up the molecular structure of Fusarium toxins, in particular trichothecenes, by deepoxidation of the molecule, at 2 kg/tonne concentration. One group (n = 10) served as positive control; their feed was free from T-2 toxin but contained the feed additive at the above concentration. Toxin concentrations at these low dietary levels impaired the feed intake and growth rate of pigs. The feed additive alleviated the negative effects and justified its potential for prevention. Data of the present study indicated a 0.2 mg/kg feed no observed effect level (NOEL) of T-2 toxin in growing pig feeds.

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Magyar Pszichológiai Szemle
Authors:
Bence Kas
,
Ágnes Lukács
,
Csaba Pléh
, and
Zoltán Jakab

GósyMária: Pszicholingvisztika (Kas Bence –Lukács Ágnes)   577Traxler, MatthewJ. –Gernsbacher, MortonA_2

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Talajok szemcseösszetételének vizsgálata előtt nélkülözhetetlen a talajban található eltérő tulajdonságú kötőanyagok feloldása, roncsolása, mivel ezeknek fontos szerepe van a mikro- és makroaggregátumok kialakításában. Ennek hiányában jelentős mennyiségű agyagszemcse marad aggregátumokban, a szemcseösszetételt, agyagtartalmat jelentősen módosítva. Jelen tanulmányban az egyik leggyakoribb ragasztóanyagnak, a talajok humusztartalmának a hatását vizsgáltuk. A statisztikai analízis eredménye szerint a humuszt bontó hidrogén-peroxidos kezelésekkel – a kontrollként használt, humusz nélküli folyóvízi homok kivételével – szignifikánsan nagyobb agyagtartalmat mérünk, mint a MSz szerinti Na-pirofoszfátos kezeléssel. A hidrogén-peroxidos előkészítéssel a talajminták szemcseösszetételének varianciája lényegesen kisebb, mint más kezeléseké, vagyis az intenzívebb előkészítő eljárásokkal a minták szemcseméret eredményeinek különbsége csökken. Az előkészítő eljárások különbségének az okát keresve a talajok humusz- és agyagtartalmának korrelációját elemeztük. A humusz az agyagtartalommal gyengén korrelált. Az 1–5. kezelésekkel kapott agyag- és a talaj humusztartalma között negatív, míg a hidrogén-peroxidos kezelések esetén gyenge pozitív kapcsolatot mutattunk ki. Az ultrahangos kezelések kiemelt jelentőségűek az előkészítésekben, de az agyagtartalomban szignifikáns különbség csak a hidro-gén-peroxidos kezelések esetén mutatható ki. Vizsgálataink megmutatták a talajminták szemcseméret elemzése előkészítésének, az ásványi szemcsék dezaggregálásának fontosságát, valamint azt, hogy a dezaggregálás elégtelensége jelentősen kisebb agyagtartalmat eredményez. Talajok szemcseméret meghatározásában, de különösen a jelentősebb szervesanyag-tartalmú talajokéban a hidrogén-peroxidos előkészítő eljárás használandó. A Na-pirofoszfátnak és az ultrahangos kezelésnek a talajminta diszpergálásában van nagy jelentősége. Szükségesnek tartjuk ezért a hazai talaj szemcseméret-elemzés szabványát (szabványait) felülvizsgálni, továbbá az európai szemcseméret-elemzési eljárások tapasztalatainak megismerését és beépítését a hazai szemcseméret analitikai gyakorlatba.

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Abstract

The thermal behaviours of a sewage sludge sample, woody (black locust, poplar and willow) and herbaceous (energy grass and wheat straw) biomass as well as mixed (sewage sludge and black locust in ratios 1:1 and 1:3) samples were compared under inert and oxidative atmosphere. The thermogravimetric experiments of each sample demonstrate that the beginning temperature of decomposition is similar in inert and oxidative atmospheres, i.e. the primary bond scissions are not affected by the atmosphere. Nevertheless, oxygen increases the decomposition rate and the volatile evolution of all samples at higher temperatures. Thermogravimetry/mass spectrometry (TG/MS) experiments have been performed to determine the mass loss of the samples and the formation of volatile products as a function of temperature in inert atmosphere. Wood and herbaceous biomass samples evolved various organic products (aldehydes, ketones, acids, furan derivatives, etc.) beside water and gaseous products. Sewage sludge released mainly water, carbon oxides, methane, hydrogen, hydrocarbons, ketones, acids as well as sulphur- and nitrogen-containing products. High heating value and low heating value of the samples have been determined by a bomb calorimeter. Principal component analysis (PCA) has been used to find statistical correlation between the data. The results unambiguously support the correlation between the thermogravimetric parameters (e.g. DTGmax) and the heating values of the samples.

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Claudins are integral membrane proteins of the tight junction structures expressed by epithelial and endothelial cells. The present study has evaluated the expression of claudin-4 in 10 normal canine hepatoid glands and in 67 hepatoid glands with hyperplastic and neoplastic lesions. The lesions studied included normal hepatoid glands (n = 10), nodular hyperplasias (n = 10), adenomas (n = 12), epitheliomas (n = 15), differentiated carcinomas (n = 15) and anaplastic carcinomas (n = 15). There was an intensive expression of claudin-4 in normal canine hepatoid glands as well as in hyperplasias and adenomas. Claudin-4 was detected as a well-localised linear circumferential membranous staining pattern of epithelial cells (mature hepatoid cells) in normal hepatoid glands, perianal gland hyperplasias and adenomas. In nodular hyperplasia and adenoma, the reserve cells showed membrane positivity for the claudin-4 molecule. There was a weaker expression in hepatoid gland epitheliomas. In the epitheliomas, the basaloid reserve cells never expressed the claudin-4 molecule. The multiple small parts of epitheliomas in which the cells exhibited typical hepatoid features showed a well-localised linear circumferential membranous staining pattern for claudin-4. The numerical score for cellular expression of claudin-4 was higher in differentiated carcinomas than in epitheliomas, but moderately lower than in adenomas. The anaplastic, poorly differentiated hepatoid gland carcinomas showed an overexpression of claudin-4. These results suggest that low claudin-4 expression in epitheliomas is a molecular characteristic indicative of increasing cellular disorientation, detachment motility and invasion by tumour cells, and claudin-4 seems to be helpful in distinguishing undifferentiated carcinomas from differentiated carcinomas and epitheliomas of the hepatoid gland. In addition, claudin-4 can help distinguish epithelioma from differentiated carcinoma of the canine hepatoid gland.

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Agrokémia és Talajtan
Authors:
Boglárka Keller
,
Judit Szabó
,
Csaba Centeri
,
Gergely Jakab
, and
Zoltán Szalai

Summary

Adaptation is the most important strategy to reduce the effect of climate change and soil erosion. During this process adequate, rational land use is necessary to ensure climate resilience. Therefore, the main objective in this study was to evaluate the susceptibility of different land use intensities (arable land and grassland) to soil erosion. The rainfall simulation method is a good tool to measure and estimate soil erosion in situ. The comparative measurements were carried out in the field with a Shower Power-02 simulator on 6 m2 plots in Gerézdpuszta, where the slope angles were ~8% and the simulated rainfall events had high intensities (~70-96 mm h−1). The runoff and soil loss were significantly higher from arable land. The runoff-infiltration ratio and runoff coefficient showed lower infiltration capacity in the case of arable land. On average, the suspended sediment loads were tenfold higher under intensive land use. In the case of grassland a moderate increase in infiltration was observed due to higher rainfall intensity, as also reported in the literature. The rainfall simulation method provides good data for soil loss estimations.

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Cereal Research Communications
Authors:
József Csajbók
,
Erika Kutasy
,
Éva Hunyadi Borbély
,
Zoltán Futó
, and
Péter Jakab
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