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51.
For a nonempty setE of nonnegative integers letH
E
p, q, a
andH
E
p
be the closed linear span of
相似文献
52.
G. Ebert 《Colloid and polymer science》1966,214(1):34-37
Zusammenfassung Es wird über Messungen der Adsorption von Lithiumbromid an unbehandelter und an Thioglykolat/CH3J behandelter Austral-A-Wolle zwischen +20 und +80 °C im Konzentrationsbereich zwischen 6 und 10 molarer L?sung berichtet.
Die Me?ergebnisse werden mit denen von differentialcalorimetrischen Untersuchungen an denselben Systemen verglichen. Dabei
ergibt sich, da? die maximal adsorbierte Menge LiBr ebenso wie die entwickelte W?rmemenge linear mit der Konzentration der
LiBr-L?sungen zunimmt. Man erkennt ferner, da? bei unbehandelter Wolle das Maximum der adsorbierten Menge LiBr mit steigender
Konzentration der L?sung nach h?heren Temperaturen verschoben wird (9 m: 47 °C; 10 m: 60 °C).
An Thioglykolat/CH3J behandelter Wolle mit 4,2% Cystin (gegenüber 11,4% der unbehandelten) tritt das Maximum der LiBr-Adsorption in 10 m-L?sung
bereits bei 40 °C auf in übereinstimmung mit den differentialcalorimetrischen Messungen.
Damit ist offensichtlich erwiesen, da? der differentialcalorimetrisch exotherme Vorgang zwischen Wolle und LiBr-L?sungen symbat
mit der Adsorption des LiBr sowohl in Bezug auf W?rmemenge als auch der Temperaturlage verl?uft.
Diese Untersuchungen werden fortgeführt, und wir werden in einiger Zeit über weitere Ergebnisse berichten.
Herrn Prof. Dr. F. H. Müller danke ich für anregende Diskussionen, der Deutschen Forschungsgemeinschaft für die gro?zügige finanzielle Unterstützung.
Frau U. Hende? hat in dankenswerter Weise bei der Durchführung dieser Arbeiten mitgewirkt. 相似文献
53.
54.
Silvia Dulanská Boris Remenec Ján Bilohuštin Miroslav Labaška Dušan Galanda 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):2189-2192
This paper describes the use of IBC’s AnaLig® Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate, and recover strontium from urine samples. This method uses two-stage columns separation consisting of two different commercial products Eichrom’s Pre-filter Material and AnaLig® Sr-01 column from IBC Advanced Technologies. This method does not involve co-precipitation of strontium as phosphates and oxalates from urine samples. The new rapid method separates strontium-90 with high chemical recovery. 相似文献
55.
56.
Poly(2‐oxazoline) hydrogels crosslinked with aliphatic bis(2‐oxazoline)s: Properties,cytotoxicity, and cell cultivation 下载免费PDF全文
Anna Zahoranová Zuzana Kroneková Miroslav Zahoran Dušan Chorvát Jr. Ivica Janigová Juraj Kronek 《Journal of polymer science. Part A, Polymer chemistry》2016,54(11):1548-1559
A series of hydrogels from 2‐ethyl‐2‐oxazoline and three bis(2‐oxazoline) crosslinkers—1,4‐butylene‐2,2′‐bis(2‐oxazoline), 1,6‐hexamethylene‐2,2′‐bis(2‐oxazoline), and 1,8‐octamethylene‐2,2′‐bis(2‐oxazoline)—are prepared. The hydrogels differ by the length of aliphatic chain of crosslinker and by the percentage of crosslinker (2–10%). The influence of the type and the percentage of the crosslinker on swelling properties, mechanical properties, and state of water is studied. The equilibrium swelling degree in water ranges from 2 to 20. With a proper selection of the crosslinker, Young's modulus can be varied from 10 kPa to almost 100 kPa. To evaluate the potential for medical applications, the cytotoxicity of extracts and the contact toxicity toward murine fibroblasts are measured. The hydrogels with the crosslinker containing a shorter aliphatic exhibit low toxicity toward fibroblast cells. Moreover, the viability and the proliferation of pancreatic β‐cells incubated inside hydrogels for 12 days are analyzed. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1548–1559 相似文献
57.
Věra Hamplová Alexej Bubnov Corresponding author Miroslav Kašpar Vladimíra Novotná Yveta Lhotáková Milada Glogarová 《Liquid crystals》2013,40(12):1463-1469
New chiral liquid crystalline materials containing a keto group and two lactate units attached to the mesogenic core have been synthesized and studied. All the new compounds show the paraelectric SmA, ferroelectric SmC* and antiferroelectric SmC*A phases each over rather broad temperature ranges. The properties of the phases were characterized by DSC, electro-optical and dielectric studies. The spontaneous polarization, tilt angle, helical pitch, and switching times were determined for the polar phases. 相似文献
58.
59.
B. Buchholz B. Kühnreich H. G. J. Smit V. Ebert 《Applied physics. B, Lasers and optics》2013,110(2):249-262
Accuracy, precision, repeatability and long-term stability, are the most important requirements to enable reliable airborne humidity measurements, which are needed for climate models or to validate e.g. remote sensing instrumentation like satellites. However, various hygrometer artifacts which depend on the individual sensor principle and the application profile frequently cause problems and significantly complicate the hygrometer choice. Sensor intercomparisons are one way of providing the information for an optimal choice. In this paper we present the first part of a blind, static, laboratory-based intercomparison of a new, calibration-free, 1.4 μm diode laser-based, optical hygrometer (SEALDH) with the two most important measurement principles for airborne hygrometry (frost-point hygrometers, FPH, and Lyman-alpha fluorescence hygrometers, LAFH). During three days of measurement, the TDL-hygrometer achieved a H2O resolution of up to 0.5 ppmv (Δt=2 sec) at tropospheric pressure and H2O concentration levels (100–800 hPa, 10 to 8000 ppmv H2O). Its absolute accuracy was investigated via blind intercomparison with two reference FPHs and a LAFH. Without any calibration of SEALDH, i.e. without a comparison to a water vapor standard, we achieve an excellent agreement with the reference sensors, with an average systematic offset (over all three days) of ?3.9 %±1.5 %, which is fully consistent with the sensor’s uncertainty bounds. Further we also reevaluated the SEALDH data of day 2 and 3 in a calibrated mode using an independent set of FPH data from the first day and found an 8-fold accuracy improvement, yielding an excellent overall relative deviation of only 0.52 %±1.5 % with respect to a LAFH and a D/FH sensor. 相似文献
60.
Miroslav Jelínek Petr Písařík Tomáš Kocourek Josef Zemek Jaroslav Lukeš 《Applied Physics A: Materials Science & Processing》2013,110(4):943-947
A hybrid PLD system with ion bombardment of films was developed. Growing DLC films were modified during the laser deposition (10 J?cm?2) by argon ions with energy in the range from 40 eV to 210 eV and cathode current of 0.15 A and 0.5 A. The content of sp2 “graphitic” and sp3 “diamond” bonds was measured using XPS. Sp3 bonds changed from 60 % to 81 %. We found the highest sp3 content for energy of 40 eV. Hardness (and reduced Young’s modulus) were determined by nanoindentation and reached 49 GPa (277 GPa). Film adhesion was studied using the scratch test and was up to 14 N for titanium substrates. Relations among deposition conditions and measured properties are presented. 相似文献
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