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91.
92.
Andrew Wisel Irene Studentsova Abdurakhim Muslinkin Ramil Garaev Valeriy Danilov Lidia Schukina 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The synthesis of dimephosphone (1) was carried out on Pudovik's reaction. 相似文献
93.
94.
F. Enrichi R. Riccò P. Scopece A. Parma A. R. Mazaheri P. Riello A. Benedetti 《Journal of nanoparticle research》2010,12(5):1925-1931
In this study, we report the comparison between Eu3+-doped silica nanoparticles synthesized by Stöber method using Eu(NO3)3 or Eu(acac)3 as precursors. The impact of different europium species on the properties of the final silica nanospheres is investigated in details in terms of size, morphology, reachable doping amount, and luminescence efficiency. Moreover, the results obtained for different thermal treatments are presented and discussed. It is shown that the organic complex modify the silica growing process, leading to bigger and irregular nanoparticles (500–800 nm) with respect to the perfectly spherical ones (400 nm) obtained by the nitrate salt, but their luminescence intensity and lifetime is significantly higher when 800–900 °C annealing is performed. 相似文献
95.
R. Carlini D. Macciò M. Pani N. Parodi G. Zanicchi M. M. Carnasciali G. A. Costa 《Journal of Thermal Analysis and Calorimetry》2013,112(1):513-517
The substitution of Sb with As in the NiSbS intermetallic compound was studied in the framework of evaluating a possible increase of the thermoelectric properties. Different NiSb1?xAsxS samples were synthesized with increasing amounts of As (0 < x < 0.66) employing a simple synthetic route using a muffle furnace. Scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy was used to investigate the microstructure. X-ray powder diffraction techniques were employed in order to study the possible existence of a solid solution between NiSbS and NiAsS compounds, as well as to identify the crystal structure and determine the lattice parameters. All compounds were found to crystallise with the NiSbS prototype (cP12-P213), with lattice parameters varying from a = 0.59341(7) nm (x = 0) to a = 0.56849(6) nm (x = 1). Good agreement with Vegard’s law was evidenced. Thermal measurements on NiSb1?xAsxS samples were carried out using DTA instruments to evaluate the thermal stability and the melting temperatures. 相似文献
96.
Irene C. Perez Caroline Le Guiner Weiyi Ni Jennifer Lyles Philippe Moullier Richard O. Snyder 《Analytical and bioanalytical chemistry》2013,405(30):9641-9653
Athletes who illicitly use drugs to enhance their athletic performance are at risk of being banned from sports competitions. Consequently, some athletes may seek new doping methods that they expect to be capable of circumventing detection. With advances in gene transfer vector design and therapeutic gene transfer, and demonstrations of safety and therapeutic benefit in humans, there is an increased probability of the pursuit of gene doping by athletes. In anticipation of the potential for gene doping, assays have been established to directly detect complementary DNA of genes that are top candidates for use in doping, as well as vector control elements. The development of molecular assays that are capable of exposing gene doping in sports can serve as a deterrent and may also identify athletes who have illicitly used gene transfer for performance enhancement. PCR-based methods to detect foreign DNA with high reliability, sensitivity, and specificity include TaqMan real-time PCR, nested PCR, and internal threshold control PCR. 相似文献
97.
The application of an experimental approach based on the load separation criterion for the determination of the point of fracture initiation in a fracture test on a ductile polymer was critically examined. To this aim, the fracture process outlined by the application of this method was related to that described by the visual analysis of the fracture surfaces obtained in fracture tests on nominally identical specimens, in which different levels of crack extension were produced. The material examined was an acrylonitrile-butadiene-styrene (ABS) resin, and the fracture tests were performed at low loading rate on single-edge notched in bending specimens.The results demonstrated that this load separation criterion based methodology is a promising approach for the determination of the point of fracture initiation, and for material fracture resistance, JIc, evaluation. The method also has experimental simplicity and a high degree of repeatability. 相似文献
98.
Irene Maijó Núria Fontanals Francesc Borrull Christian Neusüß Marta Calull Carme Aguilar 《Electrophoresis》2013,34(3):374-382
The use of SPE coupled in‐line to CE using electrospray MS detection (in‐line SPE‐CE‐ESI‐MS) was investigated for the preconcentration and separation of four UV filters: benzophenone‐3, 2,2‐dihydroxy‐4‐methoxybenzophenone, 2,4‐dihydroxybenzophenone and 2‐phenylbenzimidazole‐5‐sulphonic acid. First, a CE‐ESI‐MS method was developed and validated using standard samples, obtaining LODs between 0.06 μg/mL and 0.40 μg/mL. For the in‐line SPE‐CE‐ESI‐MS method, three different sorbents were evaluated and compared: Oasis HLB, Oasis MCX, and Oasis MAX. For each sorbent, the main parameters affecting the preconcentration performance, such as sample pH, volume, and composition of the elution plug, and sample injection time were studied. The Oasis MCX sorbent showed the best performance and was used to validate the in‐line SPE‐CE‐ESI‐MS methodology. The LODs reached for standard samples were in the range between 0.01 and 0.05 ng/mL with good reproducibility and the developed strategy provided sensitivity enhancement factors between 3400‐fold and 34 000‐fold. The applicability of the developed methodology was demonstrated by the analysis of UV filters in river water samples. 相似文献
99.
F. Farina Arboccò P. Vermaercke K. Smits L. Sneyers K. Strijckmans 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(2):931-938
The k 0 -literature has been reviewed every decade but some of its nuclear data is still more than 30 years old. Sometimes Q 0 values were adopted from the nuclear data at that time or were experimentally determined by only 1 laboratory. Other isotopes were listed with accurate pairs of (k 0 , Q 0 ) values but were also quoted as candidates for redetermination for different reasons (i.e. imprecise cadmium transmission factors, half-lives). In this work we aim at the experimental re-determination of k 0 and Q 0 values for 41 isotopes of analytical interest while introducing a methodology for simultaneous $ \bar{E}_{r} $ and Q 0 determination employing N irradiation channels. In order to satisfy the metrological level required, up to 12 repeats per standard were irradiated in up to 4 irradiation channels of the Belgian Reactor 1 (BR1, SCK?CEN) having a wide spread in neutron characteristics. Our relative percentile differences to the literature values were usually ≤10 % for Q 0 factors, ≥25 % for $ \bar{E}_{r} $ values and ≤4 % for k 0 values. Our precision and accuracy are discussed thoroughly. 相似文献
100.
Juan L. Santos María Del Mar González Irene Aparicio 《International journal of environmental analytical chemistry》2013,93(13-14):1033-1042
The occurrence of di-(2-ethyhexyl)phthalate (DEHP), nonylphenol and nonyphenol mono- and diethoxylates (NPEs) and seven polychlorinated biphenyl (PCB) congeners in different types of sludge samples is reported. The analysis of these compounds was carried out by sonication-assisted extraction and analytical determination by gas chromatography coupled with a mass spectrometry detector, following a previously described method. The applicability of the method was tested by monitoring the organic pollutants in primary, secondary, mixed, and digested-dehydrated sludge samples from two wastewater treatment plants (WWTPs) based on aerobic and on anaerobic biological stabilization. The occurrence of these compounds in sewage sludge and the influence of sludge stabilization process on the further farmland application of the sludge were evaluated. DEHP and NPEs were detected in all analysed sludge samples from both WWTPs at concentration levels in the range of 22.3–601?mg?kg?1 and 136–2357?mg?kg?1 dm (dry matter), respectively. PCBs were detected in all types of sludge analysed from the anaerobic WWTP but was not detected in any sludge sample from the aerobic WWTP. Concentration levels of the sum of the seven PCBs congeners were up to 1.5?mg?kg?1 dm. The concentration of DEHP, sum of NPEs, and sum of the seven PCB congeners were higher than the limits fixed in the third draft of the future Sludge Directive for land application of sludge in the 67%, 100%, and 11% of samples from the anaerobic WWTP and in the 83%, 92%, and 0% of samples from the aerobic WWTP, respectively. 相似文献