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Sumpor u ugljenu (Sulphur in Coal)  [PDF]
Ra?enovi?, A.
Kemija u Industriji , 2004,
Abstract: The presence of sulphur in coal possesses important environmetal problems in its usage. The sulphur dioxide (S02) emissions produced during coal combustion account for a significant proportion of the total global output of anthropogenic SO2. The extent of sulphur separation depends on several variables such as the form of sulphur in coal, intimacy of contact between minerals and the products of devolatilization. The total sulphur in coal varies in the range of 0.2 - 11 wt %, although in most cases it is beetwen 1 and 3 wt %. Sulphur occurs in a variety of both inorganic and organic forms. Inorganic sulphur is found mainly as iron pyrite, marcasite, pyrrhotite, sphalerite, galena, chalcopirite and as sulphates (rarely exceeds w = 0,1 %). Organic sulphur is found in aromatic rings and aliphatic functionalities usually as mercaptans, aliphatic and aryl sulfides, disulfides and thiophenes. Organic and pyritic sulphur quantities depend on coal rank. Higher rank coals tend to have a high proportion of labile sulphur. All the organic sulphur is bivalent and it is spread throughout the organic coal matrix. Sulphur occurs in all the macerals and most minerals. Vitrinite contains the major part of organic sulphur and metals. Elemental sulphur is produced during coal weathering. The depolymerization methods as pyrolysis and hydrogenation are very drastic methods wich change the structure of the coal and the sulphur groups. In the case of pyrolysis, high levels of desulphurization, in chars and additional production of liquid hydrocarbon can be achieved. Thiophenes and sulphides were the major sulphur components of tars from coal pyrolysis. Hyrdogen sulphide and the lower mercaptans and sulphides were found in the volatile matters. Hydrogen sulphide and thiophenes are practically the only sulphur products of coal hydrogenation. H2S is produced in char hydrodesulphurization. A number of options are available for reducing sulphur emissions including the utilisation of coals with low sulphur concentrations (typically < 1 wt %), the removal of cleaning prior to utilisation. The methods for the removal of sulphur from coal can be divided into: physical, chemical and microbiological. The mineral sulphur components can be removed or reduced by commercial methods of coal washing, flotation and agglomeration. A number of chemical desulphurization for the removal of, both, pyritic and organic sulphur have been advocated. The chemical desulphurization methods however, have two major drawbacks. Namely, they are often expensive and they destroy the caking properties of coal. Ce
On the origin of the $λ$-transition in liquid Sulphur  [PDF]
Tullio Scopigno,Spyros Yannopoulos,Filippo Scarponi,Kostas Andrikopoulos,Daniele Fioretto,Giancarlo Ruocco
Physics , 2007, DOI: 10.1103/PhysRevLett.99.025701
Abstract: Developing a novel experimental technique, we applied photon correlation spectroscopy using infrared radiation in liquid Sulphur around $T_\lambda$, i.e. in the temperature range where an abrupt increase in viscosity by four orders of magnitude is observed upon heating within few degrees. This allowed us - overcoming photo-induced and absorption effects at visible wavelengths - to reveal a chain relaxation process with characteristic time in the ms range. These results do rehabilitate the validity of the Maxwell relation in Sulphur from an apparent failure, allowing rationalizing the mechanical and thermodynamic behavior of this system within a viscoelastic scenario.
Effect of Sulphur on Health of Fayoumi Chicken
M. Alam,A. D. Anjum,M. Z. Akhtar
Pakistan Journal of Biological Sciences , 1998,
Abstract: Fayoumi birds were supplemented with 0 (control), 1, 2, 3 and 4 per cent elementary sulphur in feed from 56 days to 140 days of age. Clinically, faeces in birds fed by 2, 3 and 4 per cent sulphur were not well formed. Mortality did not differ significantly between treatments. Sulphur treatment induced a significant decrease in live body weight which was dose-related. Liver and kidneys were affected markedly. Heart and spleen were not affected. Testes weight was relatively lesser in male sulphur treated birds than the control males. The number of ovarian follicles was lesser in female sulphur-treated birds than the control females. The study suggests that prolonged use of sulphur may influence live body weight, some visceral organs and gonads in birds.
DYNAMIC SEGREGATION OF SULPHUR IN CAST IRON
QIN Ziqiang YU Zongsen University of Science,Technology Beijing,Beijing,China QIN Ziqiang,
QIN Ziqiang YU Zongsen University of Science and Technology Beijing
,Beijing,China QIN Ziqiang

金属学报(英文版) , 1989,
Abstract: The segregation of sulphur at iron/graphite interfaces in both grey and nodular iron was in- vestigated with AES.Sulphur was found to nonequilibratorily segregate at the interfaces in grey iron,but not in nodular iron.Such different behaviors of segregation,which will exagger- ate the difference of grey and nodular iron in sulphur content at iron/graphite interfaces, might be derived from the difference of solidification process between the two irons.
Metallic sulphur. "Electronic" mechanism of superconductivity?  [PDF]
V. N. Bogomolov
Physics , 1999,
Abstract: It is shown that the rapid increase of the superconducting transition temperature $T_c$ of sulphur with increasing pressure above 93 GPa does not contradict with some hypothetical ``electronic'' mechanism of superconductivity with participation of the electron interaction energy fluctuations. Such ``electronic'' mechanism is supposed to be intrinsic property of the molecular condensates and corresponds to very high $T_c$. The low $T_c$ of sulphur (10 -17)K is likely connected with the magnetic properties of the sulphur atoms and molecules. The equation of state for sulphur is obtained. The molar volume of sulphur at metallization is 10 cm}$^3${/mol. The principal difference between the ''physical'' and the ''chemical'' type bonds are discussed. Under some pressure one bond type is changed by another and}${T}_c${may have an extremum (transition from the Bose condensation to the BCS superconductivity).
Biogeochemical sulphur cycle in Haihe River Basin
Liu Quanyou,
Liu
,Quanyou

环境科学学报(英文版) , 1995,
Abstract: The charactenstics of biogeochemical sulphur cycle in Haihe River Basin were discussed in this pa-per basing on the storage and fluxes of sulphur in the hydrosphere, atmosphere, pedosphere and biospherethrough a study on the distribution character and content in them.
Nutritional significance of sulphur in pulse cropping system
TA. Khan
Biology and Medicine , 2011,
Abstract: Sulphur is a part of every living cell and is a constituent of two of the 21 amino acids which form proteins. Of allthe macronutrients, sulphur is perhaps the nutrient which has attracted the most attention in soil science andplant nutrition due to its potential defensive characteristics to pests, good nutritive potentiality to crops and itsrelative immobility in the soil-plant system. The benefits from sulphur fertilisation of crops can be traced to its rolein protein development, to improvement of nitrogen use, etc. However, the availability of sulphur needed forprofitable crop production continues to decline. This review highlights the prominent role of microbes in sulphuravailability to crop plants as well as includes the mechanism of its uptake, translocation and assimilation.Moreover, it provides new insights leading us to revisit the hypothesis of sulphur significance in pulse croppingand regulatory mechanisms in sulphur assimilation.
Modification of oxygen and sulphur inclusions in steel by calcium treatment  [PDF]
T. Lis
Metalurgija , 2009,
Abstract: In the article, the results of examinations of changes in deformability of oxygen and sulphur inclusions in structural steel processed with calcium are discussed. The results obtained imply the positive influence of the calcium additives on the changes in geometry of oxygen and sulphur inclusions related to the modification of their chemical composition.
Evolution of Regional Disparities in Poland
Teresa Czy , Jan Hauke
Quaestiones Geographicae , 2011, DOI: 10.2478/v10117-011-0016-y
Abstract: The article presents the state of and changes in the pattern of regional disparities in Poland over the years 1995-2007. The differences in the level of economic development of regions are examined in a dynamic approach on the basis of per capita income, indices of local government finances, and investment outlays. The effect of development-activating factors on regional income is considered. An answer is sought to the question of whether the growth dynamics had a favourable effect on the evolution of regional disparities in Poland.
The concentration of retail in Poland
Micha? Gazdecki
Journal of Agribusiness and Rural Development , 2010,
Abstract: The article discusses the processes of concentration taking place in retail in Poland. In spite of strong concentration processes, which took place after 2000, Poland still remains a country of dispersed retail structure. In the nearest years we can expect capital concentration (mainly takeovers) in modern trade and contract concentration (for example, merchants’ societies) in traditional trade.
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