47 research outputs found
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Adventures in maceral separation
Progress has been made in recent years in the science of maceral separation. However, there are many areas that can be improved and new areas investigated. Power of density gradient centrifugation to physically resolve macerals and submaceral species coupled with other instrumental techniques is attractive for defining the limits of coal heterogeneity as well as investigating the ability of other separation methods
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Chemically modified coal macerals. Separation, density and surface area variations
Two Argonne Premium Coals were O-alkylated and O-acylated using a variety of different reagents, and then separated using density gradient centrifugation (ADGC). The separation data suggested that the hydroxyl groups are fairly evenly distributed in the maceral particles. However, several reagents produced results counter to this generalization, and exhibited enhanced maceral separation. Comparison of ADGC densities and He densities of the modified coals showed several reactivity families that appear to be based on wettability differences. Surface areas were also measured; areas as high as 200 m{sup 2}/g were obtained for some modified coals. The data suggest that there is an optimum molecular size for the added group that leads to the large areas
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Determination of sulfur compounds in coal by mass spectrometry, correlated with XANES and XPS
The objective of this study is to identify important organic sulfur-containing compounds in the Argonne Premium Coals and in selected, separated coal macerals. In-source, desorption/pyrolysis high resolution mass spectrometry is being used to characterize the volatile species of whole coals, macerals, and their extracts. To examine the possibility of secondary reactions and undesirable selectivity, the MS data is compared to data from direct techniques, XANES and XPS. The MS results con-elate very well which supports the suggestion that the species seen are indigenous to the original sample. Therefore, specific structural assignments to the sulfur species can be made. Quantitative speciation of organic sulfur in coals has been accomplished by both XANES and XPS with what appears to be good reliability. Mass spectrometry approaches provide more detailed molecular information, but suffer from problems with sampling. In the past we have found it difficult to isolate aliphatic sulfur compounds by thermal desorption or pyrolysis due to their thermal transformation to aromatic species. However, recently we have found that with in-source pyrolysis the occurrence of secondary reactions is reduced significantly. Results from both a selected setof the Argonne Premium Coal Samples and a set of three macerals from the Listen-Stockton coal (APCS 7) are discussed
Providing passengers' safety as one the most important activities of the MPK SA in Cracow
Zapewnienie bezpiecze艅stwa w transporcie publicznym to skomplikowane zadanie. Bezpiecze艅stwo komunikacyjne jest zwi膮zane z ruchem drogowym. Coraz wi臋ksze znaczenie zyskuje bezpiecze艅stwo osobiste pasa偶er贸w, kieruj膮cych pojazdami i kontroler贸w. Do tego dochodzi bezpiecze艅stwo mienia: pojazd贸w, przystank贸w i pozosta艂ej infrastruktury. Artyku艂 przedstawia dzia艂ania prowadzone przez przewo藕nika na tym polu. Podstaw膮 jest utrzymywanie kompetentnej za艂ogi, kt贸ra poradzi sobie w skomplikowanych warunkach drogowych wielkiego miasta oraz w przypadku pojawiaj膮cych si臋 problem贸w ze strony pasa偶er贸w. Drugim znacz膮cym obszarem dzia艂a艅 jest wsp贸艂praca z instytucjami odpowiedzialnymi w mie艣cie za bezpiecze艅stwo - w artykule om贸wiono wsp贸lne akcje przeprowadzane z policj膮 i stra偶膮 miejsk膮. Przedstawiono dzia艂ania przeprowadzane w zakresie infrastruktury przystankowej, w Krakowie bowiem przewo藕nik jest odpowiedzialny za jej funkcjonowanie i utrzymanie. Poza tym skr贸towo przedstawiono wybrane statystyki dotycz膮ce: ofiar wypadk贸w, struktury przeprowadzanych kontroli i wsp贸艂pracy z innymi instytucjami.Protection of security in public transport is a complicated challenge. Transport safety is related to the road traffic. Personal passengers' as well as drivers and inspectors safety gains bigger importance. To this catalogue one should add property safety: vehicles, stops and other infrastructure elements. This article presents activities undertaken by the carrier in this scope. The basis is to employ competent staff who can manage in complicated road conditions occurring in a big city and in case of problems with passengers as well. The second important area of activities is cooperation with institutions responsible for the safety in the city. Actions executed together with the Police and the City Guard (municipal police unit) have been presented in the article. Since in Cracow it is the carrier which is responsible for maintaining of the public transport stops infrastructure, the activities related to this task have been discussed in the article as well. Besides, selected statistics concerning victims of accidents, structure of inspections and cooperation with other institutions have been presented in short
Good practices in urban public transport in Cracow to facilitate mobility for people with reduced mobility
Ci膮g艂y rozw贸j miast determinuje konieczno艣膰 wprowadzania
cyklicznych zmian w funkcjonowaniu transportu zbiorowego. W artykule
opisane s膮 dobre praktyki, jakie stosuje Miejskie Przedsi臋biorstwo
Komunikacyjne SA w Krakowie w celu ci膮g艂ego podnoszenia jako艣ci
艣wiadczonych przez siebie us艂ug. Priorytetowo traktuje bezpiecze艅stwo
w podr贸偶y oraz ci膮g艂e podnoszenie komfortu pasa偶er贸w w ich codziennych
przejazdach transportem zbiorowym w Krakowie, ze szczeg贸lnym
uwzgl臋dnieniem os贸b o ograniczonej mobilno艣ci ruchowej. Artyku艂 omawia
szereg dzia艂a艅 na r贸偶nych p艂aszczyznach, pocz膮wszy od przystank贸w
i infrastruktury towarzysz膮cej przez eksploatowany tabor, szkolenia
pracownik贸w, kt贸re sprawiaj膮, 偶e korzystanie z transportu zbiorowego
w Krakowie jest coraz 艂atwiejsze i bardziej komfortowe. Aby nad膮偶y膰 nad
zmieniaj膮cymi si臋 oczekiwaniami pasa偶er贸w oraz nowymi technologiami
dost臋pnymi w dzisiejszym 艣wiecie, niezb臋dne jest kontynuowanie wdra偶ania
innowacji, kt贸re sprawia膰 b臋d膮, 偶e transport zbiorowy b臋dzie si臋
stawa艂 coraz atrakcyjniejszy w stosunku do transportu indywidualnego,
a nie b臋dzie ma艂o dost臋pny dla os贸b o ograniczonej mobilno艣ci.Continual urban development determines necessity for cyclical
changes in the functioning of public transport. This article describes
good practices that the Municipal Transport Company in Cracow is
introducing to continuously improve quality of its services. Priority is
given to travel safety and constant improvement of passenger comfort
in their daily transport by public transport in Cracow, with particular
regard to people with reduced mobility. This article discusses a number
of activities at various levels, starting with the stops and connected infrastructure
of the rolling stock, training for employees, which makes
use of public transport in Cracow easier and more comfortable. In order
to follow changing passenger expectations and to apply new technologies
available in today's world, it is necessary to continue to implement
innovations making public transport more attractive than individual
transport and also accessible to people with reduced mobilit