The Experts below are selected from a list of 240 Experts worldwide ranked by ideXlab platform
Guangmin Zhou - One of the best experts on this subject based on the ideXlab platform.
long life li polysulphide batteries with high Sulphur loading enabled by lightweight three dimensional nitrogen Sulphur codoped graphene spongeNature Communications, 2015Co-Authors: Guangmin Zhou, Eunsu Paek, Gyeong S Hwang, Arumugam ManthiramAbstract:
There is intensive research underway into the cathode development of lithium–Sulphur batteries. Here, the authors report a lithium–Sulphur battery using nitrogen/Sulphur codoped graphene structure which displays excellent electrochemical performance with high Sulphur loading.
a flexible nanostructured Sulphur carbon nanotube cathode with high rate performance for li s batteriesEnergy and Environmental Science, 2012Co-Authors: Guangmin Zhou, Dawei Wang, Pengxiang Hou, Lichang Yin, Chang Liu, Ian R Gentle, Huiming ChengAbstract:
We report the template-directed synthesis of Sulphur–carbon nanotubes and their use to form a membrane that is binder-free, highly conductive and flexible. This nanostructured membrane is used as a self-supporting cathode without metal current-collectors for Li-S batteries. The membrane cathode has a high electrical conductivity and renders a long life of Sulphur of over 100 charge–discharge cycles. High discharge capacity of Sulphur was attained at 712 mA h gSulphur−1 (23 wt% S) and 520 mA h gSulphur−1 (50 wt% S) at a high current density (6 A gSulphur−1). The overall capacity of the flexible cathode correspondingly reaches 163 mA h g−1 (23 wt% S) and 260 mA h g−1 (50 wt% S). These results demonstrate the great potential of this nanostructured flexible membrane as a cathode for Li-S batteries with fast charge–discharge performance and long life.
Jozef Kelemen - One of the best experts on this subject based on the ideXlab platform.
Determination of Sulphur and total Sulphur dioxide in wines by an ICP-AES method.Talanta, 1998Co-Authors: Imre Sarudi, Jozef KelemenAbstract:
Abstract Sulphur contents of the original sample and the sample free from Sulphur dioxide were determined by ICP-AES following nitric acid digestion under high pressure (using PAAR HPA equipment), and the total Sulphur content was calculated from the difference between the results obtained. With the aim of preparing a sample free from Sulphur dioxide, bound Sulphur dioxide was released by sodium hydroxide, then after acidifying by phosphoric acid, boiling was carried out. Relative standard deviations of the results obtained for total Sulphur, the Sulphur without S(IV) and total Sulphur dioxide were lower than 2.5, 3.5 and 5% respectively. Various amounts of Sulphur (in the form of Na2SO4), added to wine samples, were successfully recovered between 95.5 and 104.9%. Based on comparative analyses performed by a widely accepted classic method, the indirect method developed was found to be adequate for the determination of total Sulphur dioxide. The procedure is suitable for serial tests.
M. H. Stone - One of the best experts on this subject based on the ideXlab platform.
Catalytic oxidation of Sulphur dioxide at low concentrationsJournal of Chemical Technology & Biotechnology, 2007Co-Authors: D. H. Napier, M. H. StoneAbstract:
A suggested process for removing Sulphur oxides from boiler flue gases requires as a first stage the oxidation of Sulphur dioxide to Sulphur trioxide, followed by the removal of Sulphur trioxide as ammonium sulphate or Sulphuric acid. Only work on the first stage is reported in this paper. As little attention has been given previously to the catalytic oxidation of Sulphur dioxide in flue gases, bench-scale experiments with simple apparatus were made to examine the reaction under these conditions. Four vanadium pentoxide catalysts of differing composition were compared, and the best was then used in a brief study of the following variables: contact time, Sulphur dioxide concentration, and oxygen concentration. The results suggest that it might be technically feasible to oxidise the Sulphur dioxide in flue gases, and that normal variations in flue gas composition would have little effect on the reaction.
Mrinal K. Baruah - One of the best experts on this subject based on the ideXlab platform.
A new form of Sulphur in coal: the discovery of an iron-Sulphur coordination compoundFuel, 1998Co-Authors: Mrinal K. Baruah, Probin C. GogoiAbstract:
An iron-Sulphur coordination compound in coal has been identified for the first time. Isolation of the compound from a high Sulphur Indian coal sample was performed by extracting with tetrahydrofuran followed by methanol and ultimately separated by thin layer chromatography. Characterization of the compound by proton n.m.r., i.r., u.v. and chemical analyses of iron and Sulphur reveals that iron atoms are bonded to thiophenic, aliphatic and inorganic Sulphur atoms. Geochemical studies have revealed that the main sources of Sulphur are inorganic and Sulphur amino acids mostly cysteine, cystine and methionine. Identification of the coordination compound has confirmed the nature and occurrence of secondary Sulphur in coal. This compound is considered to be a new form of Sulphur because it is neither purely pyritic nor organic Sulphur. The discovery of the Fe-S coordination compound is a great concern for the determination of the Sulphur forms in coal.
Sulphur in Assam coalFuel Processing Technology, 1996Co-Authors: Pronab K. Barooah, Mrinal K. BaruahAbstract:
Research carried out on Sulphur in Assam coals are reviewed. It is intended to provide a general overview with some recent advances on the forms of Sulphur in these coals and their deSulphurization and recovery in the forms of elemental Sulphur or useful compounds. Greater emphasis is given on a new form of Sulphur, i.e., secondary Sulphur, in Assam coals. Studies on Sulphur in Assam coals would be potentially useful in coal utilization.
Elena Karaseva - One of the best experts on this subject based on the ideXlab platform.
On the reasons for low Sulphur utilization in the lithium-Sulphur batteriesJournal of Power Sources, 2015Co-Authors: Vladimir Kolosnitsyn, E.v. Kuzmina, Elena KarasevaAbstract:
Abstract This work is to study the reasons for the relatively low efficiency of Sulphur reduction (about 75%) in lithium–Sulphur batteries. The two main reasons for that are suggested to be: the relatively low electrochemical activity of low order lithium polysulphides and blocking of the carbon framework of the Sulphur electrode by insoluble products of electrochemical reactions – Sulphur and lithium sulphide. The electrochemical activity of lithium polysulphides with different composition (Li2Sn, n = 2–6) has been studied in 1 M solutions of CF3SO3Li in sulfolane. It is shown that lithium polysulphides including lithium disulphide are able to electrochemically reduce with efficiency close to 100%. The electrochemical activity of lithium polysulphides decreases with the order. The order of lithium polysulphides affects the value of voltage of discharge plateaus but not the efficiency of Sulphur reducing in the lithium polysulphides species. The relatively low efficiency of Sulphur reduction in the lithium–Sulphur batteries is more likely caused by blocking of carbon particles in the Sulphur electrode by insoluble products of electrochemical reactions (Sulphur and lithium sulphide). This prevents the electrochemical reduction of low order lithium polysulphides and especially lithium disulphide.