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排序方式: 共有809条查询结果,搜索用时 15 毫秒
1.
Nazir Kizzie‐Hayford Doris Jaros Yvonne Schneider Harald Rohm 《International Journal of Food Science & Technology》2015,50(2):381-388
A standard method for the extraction of tiger nut milk has been introduced. It has been shown that, although milling duration improves the yield of tiger nut milk solids and its nutrient composition, there is a quantifiable loss of nutrient in the pressing residue during milk extraction. Milling duration improved the colloidal stability of the milk against creaming during 16 h of storage. A higher milling intensity resulted in the aggregation of biological polymers which resulted in colloidal destabilisation. Milling improved the lightness and stability and reduced browning rate of the tiger nut milk during storage. This report is important for the production of tiger nut milk of consistent and comparable characteristics. Milling has been introduced as a processing method for the qualitative and quantitative modulation of the properties of tiger nut milk. It is recommended to develop further strategies to improve the colloidal stability of tiger nut milk as a beverage. 相似文献
2.
Marcus Heinze Sandra Starke Marcel Händler Hartmut Komber Marco Drache Norbert Moszner Brigitte Voit Doris Pospiech 《应用聚合物科学杂志》2019,136(48):48256
We demonstrate in this study that the combination of modern inline monitoring methods [here: inline nuclear magnetic resonance (NMR)] with simulations gains more exact and profound kinetic results than previously used methods like linearization without that combination. The 1H-NMR spectroscopic data (more than 100 data points) are used to construct the copolymerization diagram. The reactivity ratios are obtained applying the van Herks nonlinear least square method. The examination of the radical copolymerization of 2-hydroxyethyl methacrylate (HEMA) with (2-{[2-(ethoxycarbonyl)prop-2-en-1-yl]oxy}ethyl) phosphonic acid (ECPPA) as important adhesive monomer used in dentistry yields reactivity ratios of rHEMA = 1.83; rECPPA = 0.42. The copolymerization diagram reflects nonideal, non-azeotropic copolymerization. The sequence distribution of the obtained by Monte Carlo simulation indicates the generation of statistical copolymers. As an important finding, it is demonstrated that the repeating units responsible for etching and adhesion are arranged over the whole polymer chain, which is necessary to achieve proper functionality. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48256. 相似文献
3.
Industries in the US continue to lose ground in international competition. If IS is to help change that trend, it will have to become more creative. Creativity improvement programs are being introduced in other areas of the company— now is the time for IS organizations to follow suit. 相似文献
4.
5.
Arafa M. Fay P. Ismail K. Chu J.O. Meyerson B.S. Adesida I. 《Electron Device Letters, IEEE》1996,17(3):124-126
We report on the fabrication and characterization of high-speed p-type modulation-doped field-effect transistors (MODFETs) with 0.7-μm and 1-μm gate-lengths having unity current-gain cut-off frequencies (fT) of 9.5 GHz and 5.3 GHz, respectively. The devices were fabricated on a high hole mobility SiGe heterostructure grown by ultra-high-vacuum chemical vapor deposition (UHV-CVD). The dc maximum extrinsic transconductance (gm) is 105 mS/mm (205 mS/mm) at room temperature (77 K) for the 0.7-μm gate length devices. The fabricated devices show good pinch-off characteristics and have a very low gate leakage current of a few μA/mm at room temperature and a few nA/mm at 77 K 相似文献
6.
7.
The effect of superconducting order parameter fluctuations on the nuclear-spin relaxation rate, 1/T 1, is studied for clean two-dimensional systems by calculating the three Maki-Thomson-type diagrams which represent the lowest-order fluctuation contributions to the transverse susceptibility. For Gaussian fluctuations and for temperatures near the mean field transition temperature,T c0, we employ a weak-coupling theory in which the pair-fluctuation propagator can also include pair-breaking effects. We also go beyond the Gaussian theory and take into account the interactions between Cooper-pair fluctuations corresponding to the fourth-order Ginzburg-Landau fluctuation terms. We compare our results with previous results in the dirty limit and in 3D. We obtain a pronounced peak in 1/T1 atT c and briefly discuss possible reasons why this peak is not observed. 相似文献
8.
1. The classical ATP sensitive K+ (K(ATP)) channels are composed of a sulphonylurea receptor (SUR) and an inward rectifying K+ channel subunit (BIR/Kir6.2). They are the targets of vasorelaxant agents called K+ channel openers, such as pinacidil and nicorandil. 2. In order to examine the tissue selectivity of pinacidil and nicorandil, in vitro, we compared the effects of these agents on cardiac type (SUR2A/Kir6.2) and vascular smooth muscle type (SUR2B/Kir6.2) of the K(ATP) channels heterologously expressed in HEK293T cells, a human embryonic kidney cell line, by using the patch-clamp method. 3. In the cell-attached recordings (145 mM K+ in the pipette), pinacidil and nicorandil activated a weakly inwardly-rectifying, glibenclamide-sensitive 80 pS K+ channel in both the transfected cells. 4. In the whole-cell configuration, pinacidil showed a similar potency in activating the SUR2B/Kir6.2 and SUR2A/Kir6.2 channels (EC50 of approximately 2 and approximately 10 microM, respectively). On the other hand, nicorandil activated the SUR2B/Kir6.2 channel > 100 times more potently than the SUR2A/Kir6.2 (EC50 of approximately 10 microM and > 500 microM, respectively). 5. Thus, nicorandil, but not pinacidil, preferentially activates the K(ATP) channels containing SUR2B. Because SUR2A and SUR2B are diverse only in 42 amino acids at their C-terminal ends, it is strongly suggested that this short part of SUR2B may play a critical role in the action of nicorandil on the vascular type classical K(ATP) channel. 相似文献
9.
E. Fay D. J. Flynn J. R. Lundehn P. J. Chapman R. D. Mason 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2007,17(3):61-77
Pflanzenschutzmittel müssen seit 1993 in den Mitgliedstaaten der Europ?ischen Gemeinschaft nach der Richtlinie 91/414/EWG
des Rates bewertet und zugelassen werden. Das Programm zur Bewertung von alten Wirkstoffen (welche vor Juli 1993 auf dem Markt
waren) beinhaltet mehrere Schritte und Stufen, die früher über einen Zeitraum von bis zu 10 Jahren zu bew?ltigen waren; heute
sind dafür jedoch 15 Jahre vorgesehen. Das Programm wurde seit 1996 von der Europ?ischen Kommission mit Unterstützung des
ECCO-Teams(European Community Co-Ordination) koordiniert. Das ECCO-Team bestand aus zwei Gruppen: eine im Pesticides Safety Directorate – PSD in York (Gro?britannien)
und eine im Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL) bzw. vor November 2002 in der Biologischen Bundesanstalt
für Land- und Forstwirtschaft in Braunschweig. Sie unterstüzten das Programm zur Bewertung von Wirkstoffen im Namen der Kommission
in technischer und administrativer Hinsicht und zeichneten sich insbesondere für das ECCO Peer Review Programm (Expertenprüfungen)
verantwortlich. Im November 2003 übernahm die Europ?ische Beh?rde für Lebensmittelsicherheit (EFSA) die Verantwortung für
die wissenschaftliche überprüfung der von den Mitgliedstaaten erstellten Bewertungen durch Experten. Das ECCO-Team leistete
jedoch weiterhin der Europ?ischen Kommission Unterstützung bei der Durchführung anderer Verfahrensaspekte, vor allem im Bereich
der Managementaufgaben der Europ?ischen Kommission. Insgesamt war das Programm au?erordentlich erfolgreich. Es wurden für
162 Wirkstoffen zwischen 1996 und 2003 der Inhalt der von den Mitgliedstaaten erstellten Bewertungsberichte durch eine Expertengruppe
diskutiert und füberprüft, was ma?geblich eine Entscheidungsfindung zur Akzeptabilitf?t dieser Wirkstoffe auf Gemeinschaftsebene
erm?glicht hat. 相似文献
10.
Dirk Anderheiden Otto Brenner Doris Klee Robert Kaufmann Horst A. Richter Christian Mittermayer Hartwig Hcker 《大分子材料与工程》1991,185(1):109-127
Different polyurethanes were synthesized by varying the diol as well as the diisocyanate components and chain extenders. Polyurethanes with OH-groups were obtained by photo- and thermoinitiation of the radical polymerization of hydroxy alkyl acrylates in the presence of the polyurethanes. The polymers were evaluated with respect to their biocompatibility by measuring the cell spreading, the rates of DNA- and protein synthesis and the swelling behaviour. The differences in the surfaces and the bulks between the selected basic polyurethane and the functionalized modification were determined and characterized by XPS, FTIR-ATR and 13C-FT-NMR-spectroscopy. The mechanical data of Tecoflex EG 60D® and Pellethane 2363–80AE® were compared with the data of the synthesized polyurethanes. 相似文献