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91.
Dursun Ali Köse Birgül Zümreoglu‐Karan Prof. Dr. Tuncer Hökelek Ertan Sahin 《无机化学与普通化学杂志》2009,635(3):563-566
The structure of [B6H9NaO14, H3BO3, 6H2O] was determined by single‐crystal X‐ray diffraction and further analyzed by FTIR spectroscopy and differential thermal/thermogravimetric analysis. The asymmetric unit contains Na–O polyhedra (distorted octahedron), [B6O8(OH)3]– fundamental building blocks, one free water molecule and one free H3BO3 molecule. In the hexaborate anion, three B3O3 rings are linked by a common oxygen atom with five trigonal and one tetrahedral boron atoms. The hexaborate group is also linked to the oxygenated environment of the sodium atom by three other six‐membered rings, each of which involve two boron atoms, three oxygen atoms, and sodium as the joint atom. 相似文献
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93.
一个解剖基人体下肢的生物动力模型--第三部分:肌肉效应 总被引:1,自引:0,他引:1
本将人体下肢的肌肉根据其解剖特征,分为5个肌群,并在由本第一部分所建立的基本的解剖基模型的基础上,计入其对人体下肢动力运动的效应。本所建立的5个肌群,则主要代表着膝关节处的运动和稳定肌。最后,作为应用,研究了一个献中的特例。 相似文献
94.
Statistical copolymers of perfluoroalkyl ethyl methacrylate (Zonyl-TM) and styrene (S) were synthesized in CO2-expanded monomer medium at a low initial pressure of 25 MPa. Different Zonyl-TM/S feed ratios were used during copolymerizations, and it was determined that the increase in the Zonyl-TM content and decrease of the CO2 amount in the comonomer feed resulted in a decrease of the molecular weights of copolymers due to earlier precipitation of copolymers giving shorter chains. The cloudy CO2-expanded liquid monomer phase was found to be the main loci of copolymerization. In addition, the increase in the Zonyl-TM feed ratio resulted in an increase in the critical degree of the polymerization time (J crit) as the time when the copolymer chains start to precipitate. The higher the Zonyl-TM content used in the feed, the higher the J crit time and the lower the weight-average molecular weight (M w) of the copolymer obtained. Thermal analysis results of the copolymer indicated that the copolymers are stable up to 387–403 °C. 相似文献
95.
Mustafa Hulusi Ugur Hasan Kılıç Mustafa Lütfü Berkem Atilla Güngör 《Chemical Papers》2014,68(11):1561-1572
UV-cured caprolactone-based polyurethane acrylate (PUA) polymer blend electrolytes were prepared and characterised. To develop polymer electrolytes suited to ambient temperature, an ionically-conductive and reliable polymer electrolyte based on urethane acrylate resins synthesised from a fluorine-containing di-functional oligomer 6F ethoxylated diacrylate, a di-functional reactive diluent 1,6-hexanediol diacrylate for adjusting the viscosity, and a radical photo-initiator doped with a mixture of lithium salts were used. Free-standing flexible electrolyte films were prepared by UV-curing via free-radical photopolymerisation. The performance of the lithium polymer cell system (Li/PE(F4)/LiCoO2) was determined by electrochemical impedance spectroscopy, cyclic voltammetry, a galvanostatic recurrent differential pulse, chronocoulometry and chronoamperometry. The electrolyte with optimal amounts of fluorine-containing oligomer and optimal salt mixture content exhibited enhanced conductivity, showing a conductivity of 1.00 × 10?4 S cm?1 at ambient temperature. The specific capacity, specific energy and specific power of a Li/PE(F4)/LiCoO2 cell were also determined. 相似文献
96.
Hilal Goktas Xiaoxue Wang Asli Ugur Karen K. Gleason 《Macromolecular rapid communications》2015,36(13):1283-1289
The synthesis and characterization of poly(3,4‐ethylenedioxythiophene) (PEDOT) using water‐assisted vapor phase polymerization (VPP) and oxidative chemical vapor deposition (oCVD) are reported. For the VPP PEDOT, the oxidant, FeCl3, is sublimated onto the substrate from a heated crucible in the reactor chamber and subsequently exposed to 3,4‐ethylenedioxythiophene (EDOT) monomer and water vapor in the same reactor. The oCVD PEDOT was produced by introducing the oxidant, EDOT monomer, and water vapor simultaneously to the reactor. The enhancement of doping and crystallinity is observed in the water‐assisted oCVD thin films. The high doping level observed at UV–vis–NIR spectra for the oCVD PEDOT, suggests that water acts as a solubilizing agent for oxidant and its byproducts. Although the VPP produced PEDOT thin films are fully amorphous, their conductivities are comparable with that of the oCVD produced ones.
97.
Mehmet Gokhan Caglayan Hilal Torul Feyyaz Onur Ugur Tamer 《Journal of Raman spectroscopy : JRS》2015,46(9):802-806
In this paper, we proposed two sensitive surface‐enhanced Raman spectroscopy assays for the determination of modafinil in urine matrix. In the first assay, modafinil was extracted by solid phase extraction and determined after sandwiching with silver nanoparticles. In the second assay, modafinil was extracted by non‐specific interaction with magnetic gold nanoparticles and determined by sandwiching with magnetic gold and silver nanoparticles. The non‐specific magnetic extraction does not require any analyte specific agent like antibody, aptamer, or molecularly imprinted polymer, therefore, the cost and complexity of the assay is very low. Both assays are capable for application to urine samples with the detection limits under the minimum required performance limit of modafinil. The assays were validated in terms of accuracy, precision, detection limits, and ranges. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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99.
Songul Akbulut Barbara Krupińska Anna Worobiec Ugur Cevik Halim Taskın Rene Van Grieken Lucyna Samek Ewa Wiłkojć 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1567-1573
PM-10, PM-2.5 and PM-1.0 concentrations were measured over an 8 h period at sites both inside and outside the museum of Wawel Royal Castle in Cracow, Poland. Gross alpha (α) and beta (β) activities seemed to vary across the particle size range with generally higher levels of activities in the PM-2.5 particle fraction, and higher activities in the PM-10 fraction, while both the highest and the lowest beta activities were found in PM-1.0 fraction. However, statistically there was no significant difference. The highly radioactive PM-1.0 fraction comprised mainly 210Pb and the 210Pb progeny, 210Bi and 210Po, and can be attributed to anthropogenic sourced outdoor radioactive particles brought indoors by visitors. 210Pb is considered to be a good tracer of secondary aerosols produced by gas-to-particle conversion. Inside the Museum, the highest level of gross alpha activity was detected in the PM-10 fraction, and was mainly due to the uranium isotopes (234U, 235U and 238U) and their daughter products (226Ra, 232Th, 210Po or 224Ra), and 137Cs. The minimum and maximum total indicative doses per 8 h are caused by 137Cs and 232Th, respectively. 相似文献
100.
Hadi Abou‐Chakra Pierre Chapelle Ugur Tüzün John Baxter Mayur Patel Mark Cross Ian Bridle MichaelS.A. Bradley 《Particle & Particle Systems Characterization》2004,21(1):39-46
The evaluation or design of a granular material handling process requires reliable data if executive decisions are to be made. Material behavior in a given process is usually investigated by collecting and analyzing material samples from different locations within the system. However, sampling can be a significant source of errors, as a poor sampling method can lead to measurements not truly representative of the real process. 相似文献