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1
The existence of two isomeric forms of monofluorinated hydrogen sulfide: a new theoretical rationale for experimentally observed infrared spectrum
100%
Babinec P. , Leszczyński J.
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1998
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tom Vol. 72, nr 7S
1630-1634
EN
In order to explain the discrepancies between the matrix isolated IR spectra of the products of the H2S + F2 reaction and recent computational studies of this system, we have analyzed the potential energy surface of monofluorinated hydrogen sulfide using high level post-Hartree-Fock methods. The molecular geometric and harmonic vibrational frequencies were calculated at the DFT, MP2, and CCSD levels conjunction with the 6-311++G(d,p) basis set. Besides the already proposed HSF isomer which corresponds to the global energetic minimum, a local minimum corresponding to the HFS isomer as well as a transition state structure between these minima have been also characterized. The calculated vibrational frequencies fit well with the experimental IR spectra and also complement previous ab initio calculations on the HSF isomer.
2
Content available remote Sulfur in the marine environment
100%
Jasińska A. , Burska D. , Bolałek J.
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2012
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tom Vol. 41, No. 2
72-81
EN
Sulfur is an element commonly occurring in the environment. It is present in the atmosphere, in the hydrosphere, and in live organisms; it is one of the most important physicochemical and geological indicators. Depending on the natural conditions, sulfur compounds in the environment may play the role of electron acceptor or donor in the redox processes. These compounds influence the ion concentration and ion balance in benthic sediments. They also determine the speciation, bioavailability and toxicity of heavy metals. Comprehensive knowledge of the processes mediated by sulfur can be a valuable source of information about the past and present state of the ecosystem.
3
Content available Parenteral Na2S, a fast-releasing H2S donor, but not GYY4137, a slow-releasing H2S donor, lowers blood pressure in rats
86%
Drapala A. , Koszelewski D. , Tomasova L. , Ostaszewski R. , Grman M. , Ondrias K. , Ufnal M.
Acta Biochimica Polonica
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2017
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tom 64
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nr 3
561-566
EN
Hydrogen sulfide (H2S) is involved in blood pressure regulation. We evaluated hemodynamic effects of Na2S and morpholin-4-ium (4-methoxyphenyl)(morpholino)phosphinodithioate (GYY4137), H2S donors. GYY4137 is the most widely studied slow-releasing H2S donor, however, its ability to release H2S under physiological conditions is unclear. Hemodynamics were recorded in anaesthetized Wistar-Kyoto rats at baseline and after intravenous (IV) or intraperitoneal (IP) administration of either a vehicle (20% dimethyl sulfoxide), GYY4137 or Na2S. The stability of GYY4137 in buffers and in plasma was evaluated with nuclear magnetic resonance. The vehicle, as well as GYY4137, given IV did not affect mean arterial blood pressure (MABP), whereas Na2S produced a significant decrease in MABP. Similarly, IP given Na2S, but not GYY4137, lowered MABP. In the buffers at pH of 7.4 and 5.5 and in rat plasma no reaction of GYY4137 was found during 18 hours of observation. In contrast, rapid decomposition of GYY4137 occurred in buffers at pH 2.0. In conclusion, parenteral GYY4137 does not exert a hemodynamic effect in Wistar-Kyoto rats. This seems to be due to the high stability of GYY4137 at physiological pH. Therefore, it is likely that widely reported biological effects of GYY4137 are not H2S-dependent but may depend on GYY4137 itself. However, the H2S-dependent biological effects of GYY4137 may be expected in tissues characterized by low pH.
4
Content available remote Decomposition of hydrogen sulfide in organic materials
86%
Pawłowska M. , Zdeb M. , Montusiewicz A. , Lebiocka M.
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2009
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tom Vol. 35, nr 3
157-165
EN
Organic materials (mainly composts, bark and shavings, heather twigs) are the substances most often used as packing beds in biofilters. The aim of the study was to evaluate the rate of hydrogen sulfide removal in pine bark. The initial concentration of hydrogen sulfide was up to 58% v/v. The removal rates of this gas, using the pine bark bed, ranged from 0.003 cm3 g -1 min-1 (115.64 g m-3 h-1) to 0.040 cm3 g-1 min-1 (1541.85 g m-3 h -1). The results of a preliminary test suggest that the process is abiotic. In order to eliminate biotic pathways of hydrogen sulfide removal, the samples were sterilized.
5
Content available Hydrogen sulfide generation from l-cysteine in the human glioblastoma-astrocytoma U-87 MG and neuroblastoma SHSY5Y cell lines
86%
Bronowicka-Adamska P. , Bentke A. , Wróbel M.
Acta Biochimica Polonica
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2017
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tom 64
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nr 1
171-176
EN
Hydrogen sulfide (H2S) is endogenously synthesized from l-cysteine in reactions catalyzed by cystathionine beta-synthase (CBS, EC 4.2.1.22) and gamma-cystathionase (CSE, EC 4.4.1.1). The role of 3-mercaptopyruvate sulfurtransferase (MPST, EC 2.8.1.2) in H2S generation is also considered; it could be important for tissues with low CTH activity, e.g. cells of the nervous system. The expression and activity of CBS, CTH, and MPST were detected in the human glioblastoma-astrocytoma (U-87 MG) and neuroblastoma (SHSY5Y) cell lines. In both cell lines, the expression and activity of MPST were the highest among the investigated enzymes, suggesting its possible role in the generation of H2S. The RP-HPLC method was used to determine the concentration of cystathionine and alpha-ketobutyrate, products of the CBS- and CTH-catalyzed reactions. The difference in cystathionine levels between cell homogenates treated with totally CTH-inhibiting concentrations of dl-propargylglycine and without the inhibitor was used to evaluate the activity of CBS. The higher expression and activity of CBS, CTH and MPST in the neuroblastoma cells were associated with more intensive generation of H2S in the presence of 2 mM cysteine. A threefold higher level of sulfane sulfur, a potential source of hydrogen sulfide, was detected in the astrocytoma cells in comparison to the neuroblastoma cells.
6
Wpływ obciążeń cyklicznych oraz statycznych na trwałość materiałów konstrukcyjnych w środowiskach siarkowodorowych
72%
Pashechko M. , Radkewycz O. , Czumało G. , Jurkewycz R.
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2011
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tom nr 2
24-27
PL
Urządzenia wykorzystywane w przemyśle naftowym oraz gazowym, w tym hydrotechniczne budowy, podlegają wpływom statycznego, sumarycznego i cyklicznego obciążenia w trakcie wydobycia ropy naftowej. Niektóre gazowe złoża zawierają siarkowodór, który powoduje powstanie pęcherzy, pęknięć zainicjowanych wodorem, pękanie związane z wpływem środowiska siarczkowego i korozją oraz naprężeniami. Wpływa to negatywnie na trwałość elementów maszyn pracujących przy wydobyciu ropy naftowej.
EN
Oil and gas fields equipment, including hydraulic facilities, is subjected to the effect of static, cycling loading and summary static and cyclic loading during operation. Some of gas fields contain hydrogen sulfide - one of the dangerous component that causes blistering, hydrogen induced cracking, sulfide stress corrosion cracking, and intensive total corrosion of metal. This factors influence negative on serviceability of oil and gas equipment.
7
Content available remote Usuwanie siarkowodoru z gazu biologicznego za pomocą metod z wykorzystaniem procesów mikrobiologicznych. Mechanizmy procesu, wyniki badań laboratoryjnych i przykłady zastosowań technicznych
72%
Piskowska-Wasiak J.
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2008
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tom R. 64, nr 6
381-392
PL
W artykule zaprezentowano możliwości zastosowania metod biologicznych w celu usunięcia siarkowodoru z gazów biologicznych. Określono wymagania co do zawartości siarkowodoru w gazie, w zależności od przewidywanego jego wykorzystania. Omówiono mechanizmy usuwania siarkowodoru przy wykorzystaniu mikroorganizmów i właściwości bakterii stosowanych w tym celu. Przedstawiono wyniki badań laboratoryjnych i wdrożeń technologii z zastosowaniem mikrobiologicznego usuwania siarkowodoru z biogazu.
EN
The article presents the possibilities of hydrogen sulfide removal from biogas streams using biological processes. The requirements of hydrogen sulfide content are discussed depending on the anticipated biogas application. The species of bacteria suitable for hydrogen sulfide biooxidation and mechanisms of their acting are described. The paper reviews results of successful laboratory research and the examples of microbiological hydrogen sulfide removal from biogas in commercial scale.
8
Content available remote Oznaczanie siarkowodoru w próbkach biologicznych
72%
Chwatko G.
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2010
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tom [Z] 64, 3-4
243-262
EN
Hydrogen sulfide is a well known toxic gas that has recently been synthesized from the amino acids by the use of two enzymes (Fig. 1): cystathionine-β-synthase and cystathionine-γ-lyase [1–3, 16, 17]. Hydrogen sulfide is a signaling molecule of the inflammatory and nervous systems, and in particular the cardiovascular system where it regulates vascular tone, cardiac work, and exerts cardioprotection [2, 3, 16,17, 16–21, 29]. The endogenous metabolism and physiological functions of H2S position this gas well in the novel family of gasotransmitters together with nitric oxide and carbon monoxide. This review summarizes the methods of hydrogen sulfide determination in biological samples. Biological tissue preparation procedures can include different steps: homogenization [7, 9, 10, 12, 19, 23–25, 29, 32–35], H2S release from tissues [9–14, 29], derivatization (Scheme 1–3) [1, 5, 6, 8, 11, 12, 23–25, 29], and deproteinization [23–25, 30, 31, 33, 42, 43]. Finally analysis is possible by various methods, including spectrophotometry [6, 8, 11, 23–25, 34], high-performance liquid chromatography [6, 12–14, 29, 31, 41], gas chromatography [9–11, 27, 29, 32], potentiometry [22, 35, 36, 45] and polarography [19, 30]. However, there is much doubt about the reliability of the assay methods used. Determination of hydrogen sulfide is often hindered by numerous artifacts, as: the instability of sulfide, its high volatility, its great susceptibility to oxidation, its adherence to various materials (e.g. glass). This might lead to artificially elevated or lowered levels and explains the large discrepancy among the various reports.
9
Content available Siarkowodór a układ krążenia
72%
Pacholec J. , Olas B.
Folia Medica Lodziensia
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2015
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tom 42
|
nr 1
63-74
EN
Hydrogen sulfide is a simple, non organic chemical compound with the general formula of H2S. It has very characteristic odour similar to rotten eggs. H2S is heavier than air and it has very good dissolution in water (it occurs in the form of ions). Hydrogen sulfide takes part in a lot of important functions and has a positive impact on many systems like the excretory, nervous and circulatory system. Studies have shown that the role of hydrogen sulphide in the cardiovascular system is vast and complex. This compound is involved in many essential processes for our body associated with angiogenesis, blood clotting action and blood platelet activation. It has been investigated that H2S takes part in the protection against atherosclerosis.
PL
Siarkowodór to prosty, nieorganiczny związek chemiczny o ogólnym wzorze H2S. Jego cechą charakterystyczną jest zapach – przypomina on aromat zgniłego jajka. Jest to związek cięższy niż powietrze, bardzo dobrze rozpuszczalny w wodzie (występuje w niej w postaci jonów). Siarkowodór spełnia wiele bardzo ważnych funkcji w organizmie człowieka i ma pozytywny wpływ na wiele układów – między innymi na układ wydalniczy, nerwowy czy układ krążenia. Badania dowiodły, iż rola siarkowodoru w układzie krążenia jest różnorodna. Związek ten uczestniczy w wielu istotnych dla naszego organizmu procesach związanych z angiogenezą, krzepnięciem krwi czy aktywacją płytek krwi oraz chroni przed miażdżycą.
10
Content available remote Examination of biogas hydrogen sulphide sorption on a layer of activated bog ore
58%
Gaj K. , Cybulska H. , Knop F. , Steininger M.
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2008
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tom Vol. 34, nr 4
33-41
EN
The efficiency of hydrogen sulphide removal from biogas using bog ore-based desulphurizing pulp is investigated. Measurements were carried out on quarterly basis over a five-year period in one of Polish municipal sewage treatment plants. Measurement results are presented as a function of H2S removal efficiency drop over time, with the resulting times of desulphurizing layer breakthrough compared with theoretical calculations. Sorption capacity, per unit consumption, and relative cost of the sorbent were estimated, which allows the results to be generalized and applied in comparable treatment plants.
PL
Przedstawiono wyniki badań nad skutecznością usuwania siarkowodoru z biogazu za pomocą masy odsiarczającej utworzonej na bazie rudy darniowej. Pomiary wykonywano co kwartał, przez pięć lat, w jednej z krajowych oczyszczalni ścieków miejskich. Wyniki pomiarów opracowano w postaci zależności zmniejszania się skuteczności usuwania H2S od czasu, a uzyskane czasy "przebicia" złoża porównano z czasami obliczonymi teoretycznie. Określono chłonność, jednostkowe zużycie oraz oszacowano względne koszty sorbentu, co pozwoliło uogólnić wyniki badań i wykorzystać je w podobnych obiektach.
11
Content available Ograniczenie wpływu produkcji zwierzęcej na środowisko
58%
Romaniuk W. , Domasiewicz T. , Karbowy A. , Wardal W. J.
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2009
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tom R. 13, nr 1
233-242
PL
Wolnostanowiskowe, ściółkowe systemy chowu krów, które były przedmiotem badań, zapewniają zwierzętom odpowiednie warunki utrzymania poprzez ułatwienie swobody przemieszczania się, dostępu do paszy, odpoczynku zgodnie z wymaganiami w zakresie dobrostanu. Badania mikroklimatu w oborach przeprowadzono w dwóch okresach: wiosenno-letnim i jesiennym. Wilgotność względna w okresie wiosennym kształtowała się na odpowiednim poziomie zgodnie z zaleceniami standardów technologicznych [Romaniuk, Overby i in. 2005]. Ochładzanie katatermometryczne na wiosnę mieściło się w granicach komfortu termicznego. We wszystkich oborach wilgotność kształtowała się powyżej dopuszczalnej granicy 80%. Wiązało się to głównie z pogodą deszczową na zewnątrz obiektów. Obliczone zależności wilgotności względnej wewnątrz budynku z zewnętrzną wykazały wysoką korelację (r = 0,95, r = 0,72, r = 0,70). Prędkość ruchu powietrza w oborach w okresie jesiennym wahała się w granicach dopuszczalnych (0,141 - 0,423 mźs-1).
EN
Loose, mulch type cow breeding systems, which were the subject of the research, guarantee proper living conditions for animals by making it easier for them to move, facilitating access to feed, and rest according to the requirements regarding well-being. Microclimate was examined in cowsheds in two periods: spring-summer and autumn. In spring season relative humidity ranged at suitable level, according to guidelines specified in technological standards [Romaniuk, Overby et al., 2005]. In spring katathermometric cooling ranged within thermal comfort limits. In all cowsheds humidity was above acceptable limit of 80%. This was mainly due to rainy weather outside the facilities. Computed dependences between relative humidity inside building and outside it proved high correlation (r = 0.95, r = 0.72, r = 0.70). Air motion velocity in cowsheds in autumn season oscillated within permissible limits (0.141 - 0.423 mźs-1).
12
Content available remote Method of simultaneous measurement of total sulfur, chlorine and fluorine content in biogas
44%
Gaj K. , Cybulska H. , Knop F.
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2011
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tom Vol. 37, nr 1
23-30
EN
The method of determination of total content of sulfur, chlorine and fluorine compounds in biogas has been implemented and verified at real conditions. The laboratory plant and the results of periodical measurements of the composition of biogas have been described. The main effects of the research are: determination of the range of concentrations for the analysed compounds in a typical biogas from sewage sludge digestion and evaluation of average fraction of sulfur from hydrogen sulfide in total sulfur content during multiannual period.
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