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[en] Full text: Polarization-dependent Raman spectroscopic measurements of Stibnite, Sb2S3, a naturally occurring mineral with semiconducting properties and a band gap of approximately 1.4 -1.7 eV, have been performed for various orientations of the mineral using both an infrared and a visible laser excitation line (1064 nm and 514.53 nm, respectively). The polarization dependent analysis yields the 10 Ag, 5 B1g, 10 B2g, and 5 B3g Raman active modes from the five non-equivalent sites. The results obtained are presented and discussed. (author)
[en] By the methods of physicochemical analysis interaction over Sb2S3-Sm cross section in ternary system Sm-Sb-S is studied its phase diagram is plotted. It is ascertained that Sb2S3-Sm cross section is a nonquasibinary cross section. On the basis of Sb2S3 solid solutions are formed, which contain up to 2 mol.%Sm at 300 K
[en] Complete text of publication follows. It is known that most of the brake pads contain Sb2S3 as lubricant to achieve better friction stability. Due to braking the brake lining crumbles away and its Sb content gets into the air. As a result of the temperature increase accompanying the braking a part of the antimony may oxidize to oxides, as Sb2O3 or even to the more stable form, Sb2O4. Since Sb2O3 more readily soluble than the others, its absorption from the lung so its environmental impact effect is more harmful. After a systematic investigation involving solubilization of the solid compounds, citric and tartaric acid as well as 6 mol/dm3 HCl were tested for leaching of trace antimony compounds from natural matrix. To prepare reference material related to these species, soil and activated charcoal was spiked in 10 μg/g concentration with all the three material (Sb2S3, Sb2O3,Sb2O4). separately. Recovery of the different forms was checked by graphite furnace atomic absorption spectrometric (GFAAS) analysis of the leachates. The soil was confirmed to oxidize the sulfide content while the activated charcoal was established to enrich antimony from HCl solution as ion association complex. It was concluded, that Sb2S3 is leached only in slight amount in 4 hours by 0.1-0.5 mol/dm3 citric acid, while leaching of Sb2O3 is quantitative. On the other side, it was proved that Sb2O3 as well as Sb2S3 traces are soluble in 6 HCl solution in 60 min, whilst Sb2O4 is not destroyed. So, the Sb2O3 and Sb2S3 content of a flying dust can be determined. The GFAAS temperature program had to be modified in order to be capable to analyze high organic matrix as citric or tartaric acid even in 0.5 mol/dm3 concentration. Concerning their decomposition temperature an additional step was inserted into the temperature program, pyrolysis on 300 and 400 deg C, respectively. The antimony concentration of the highly acidic leachates were determined by hydride generation GFAAS. The reproducibility of the whole procedure (sampling, leaching and analysis) was about 7%. The analytical results of some real samples are presented This research was financially sponsored by the National Foundation for Scientific Research through grant No. F61699.
[en] Sub-10 nm semiconducting nanostructures are crucial for the realization of nanoscale devices. Fabrication of nanostructures at this scale with homogeneous properties is challenging. Using ab initio calculations, we show that self-standing ribbons of antimony selenide and antimony sulfide of width 1.1 nm exhibit well-defined bandgaps of 1.66 and 2.16 eV, respectively. Molecular dynamics studies show that these ribbons are stable at 500 K. The one-dimensional (1D) heterostructure of these nanoribbons (Sb2Se3/Sb2S3) along the  direction shows a straddling type behavior.
[en] Highlights: • Sb2S3/C composite nanorods were synthesized successfully by an L-cysteine-assisted solvothermal treatment. • Sb2S3/C composite delivered a high reversible specific capacity of 1084 mA h g−1. • Sb2S3/C composite showed a good cyclability and a superior rate capability. -- Abstract: Hierarchical Sb2S3/C composite nanorods are synthesized successfully by a novel L-cysteine-assisted solvothermal treatment. The as-synthesized Sb2S3/C composite is found to display a high reversible specific capacity of 1084 mA h g−1 at a current density of 100 mA g−1, a good cyclability of 960 mA h g−1 at a current density of 100 mA g−1 after 30 cycles, and a superior rate capability of 1019 mA h g−1 at a current density of 4000 mA g−1 when evaluated as an electrode candidate material for lithium-ion batteries
[en] Highlights: •We studied the donor Sn-doped Cu(In,Ga)Se2 or CIGSe bulks at different Cu contents. •Cu-less CIGSe is used to control carrier concentration but easily loss mobility. •Sn doping here is to control the carrier concentration but keep high Cu content. •By changing the Cu content, n- and p-type CIGSe with good properties were achieved. •The CIGSe absorber shows the property diversity with the donor doping. -- Abstract: The elaborated Sn-doped Cu(In,Ga)Se2 (Sn-CIGSe) bulk materials with different Cu ratios had been sintered at 650 °C. Sn-CIGSe was reactively sintered with Sb2S3 and Te sintering aids. Electrical properties of Sn-CIGSe were measured and the variations in mobility, charge carrier density, and conductivity were rationalized. The Sn4+ donor in Cu-poor CIGSe favored the n-type behavior and the Cu deficiency increased electron concentration due to the formation of the indium-to-copper donor. The n → p transition for the Cu-rich Sn-CIGSe is related to the partial formation of the copper-to-indium and Sn2+ acceptor. Carrier mobility above 12 cm2/V s can be achieved for Sn-CIGSe with a higher Cu content. The advantages of Sn doping in CIGSe were claimed
[en] Indirect radioactive isotope lymphography using intravenous 99 m Tc-labelled colloidal antimony sulfide was performed on 76 patients with lymphoedema of the upper limb consecutive to surgery or radiotherapy. The time required to reach 50% of maximum radioactivity was taken as index of the lymphatic flow rate, and the patients were divided into 3 groups depending upon the index (<20 min; 20-60 min; >60 min). It appears that in huge lymphoedemas the lymphatic flow rate index may remain subnormal, owing to associated veno-occlusive oedema. This non-invasive method provides data on the site and, frequently on the nature and importance of lymph blockade. It might also help to predict the efficacy of a new drug currently under study
[fr]La lymphographie isotopique indirecte utilisant un sulfure colloidal marque au technetium 99m a ete faite chez 76 malades ayant un lymphoedeme post-chirurgical ou radiotherapique du membre superieur. Un indice de debit lymphatique est propose pour classer les lymphoedemes en 3 groupes: c'est le temps mis pour atteindre 50% de la radioactivite maxima. Il apparait que cet indice de debit peut rester subnormal meme en cas de lymphoedeme monstrueux. Dans ces cas, un veinoedeme est toujours associe au lymphoedeme. Cette methode atraumatique renseigne egalement sur le siege et souvent la nature du blocage, evaluant son importance. Nous pensons que cet indice de debit lymphatique peut aider a prevoir l'efficacite d'un traitement medical actuellement a l'etude