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21.
Three new cyclolignan esters and seven known compounds including two cyclolignan isolariciresinol, lynoiresinol, and five aromatic compounds methyl ferulate, vanillin, 4-hydroxy-3,5-dimethoxybenaldehyde, 4-methoxygallic acid, gallic acid were isolated from n-butanol extract of Rhus semialata (Anacardiaceae). The structural elucidations of rhusemialins A (1), B (2), and C (3) were based on FAB-MS, 1D and 2D NMR spectra. 相似文献
22.
以油溶性过氧化羟基异丙苯(CHP)为氧化剂,Al2O3为催化剂,引入超声作用,以正辛烷为模拟油品对油中二苯并噻吩的氧化进行了研究。考察了反应温度、反应时间、催化剂用量、氧硫比、超声功率对二苯并噻吩(DBT)降解率的影响并进行了正交实验,结果表明,各因素影响程度大小依次为:反应温度>催化剂用量>超声功率>反应时间>氧硫比,在反应温度为70℃,反应时间为45 min,氧硫比为5:1,催化剂用量为0.3 g,超声功率为60 W的最佳氧化条件下,DBT的降解率达到了88.0%。 相似文献
23.
Zusammenfassung Es wurde die eindimensionale Schichtenströmung pseudoplastischer Potenzflüssigkeiten in einem laminaren wellenfreien Film untersucht, der senkrecht an einer in der Strömungsrichtung harmonisch oszillierenden ebenen Platte herabfließt.Das zugehörige mathematische Modell wurde für eine Reihe der den Vorgang bestimmenden Parameter gelöst und mit entsprechenden experimentell ermittelten Daten verglichen. Die gewonnenen Resultate zeigen einen markanten Einfluß der Vibrationen auf die Filmströmung konzentrierter Suspensionen, der mit dem aufgestellten mathematischen Modell gut erfaßt werden kann.
Mit 4 Abbildungen 相似文献
Summary The one dimensional shear flow of pseudoplastic power-law fluids in a laminar nonwavy film, flowing down along an oscillating vertical flat plate, has been studied both theoretically and experimentally.The corresponding mathematical model has been solved numerically for a set of values of the governing parameters and the results have been compared with the experiments. The agreement between the theoretical and experimental values is reasonably good; the results show a pronounced influence of vibrations on the film flow of concentrated suspensions.
Mit 4 Abbildungen 相似文献
24.
Adler J Becker JJ Blaylock GT Bolton T Brown JS Bunnell KO Burnett TH Cassell RE Coffman D Cook V Coward DH Dorfan DE Dubois GP Duncan AL Eigen G Einsweiler KF Eisenstein BI Freese T Gladding G Grab C Grancagnolo F Hamilton RP Hauser J Heusch CA Hitlin DG Izen JM Köpke L Li A Lockman WS Mallik U Matthews CG Mir R Mockett PM Mozley RF Nemati B Odian A Parrish L Partridge R Perrier J Pitman D Plaetzer SA Richman JD Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Simopoulos C 《Physical review letters》1987,59(14):1527-1529
25.
Adler J Becker JJ Blaylock GT Bolton T Brown JS Bunnell KO Burnett TH Cassell RE Coffman D Cook V Coward DH Dorfan DE Dubois GP Duncan AL Eigen G Einsweiler KF Eisenstein BI Freese T Gladding G Grab C Grancagnolo F Hamilton RP Hauser J Heusch CA Hitlin DG Izen JM Köpke L Li A Lockman WS Mallik U Matthews CG Mir R Mockett PM Mozley RF Nemati B Odian A Parrish L Partridge R Perrier J Pitman D Plaetzer SA Richman JD Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Simopoulos C 《Physical review letters》1988,60(14):1375-1378
26.
W. Manchot H. Gall J. König O. Scherer H. R. Ambler T. C. Sutton T. J. Drakeley H. Nicol P. Schuftan A. T. Larson C. W. Whittaker A. B. Lamb W. E. Vail P. Lebeau P. Marmasse J. I. Graham C. de la Condamine A. Thau J. Thorbun L. Wein H. Lent H. Kast H. Selle M. Nicloux S. H. Katz G. Wittig J. E. Underwood A. Krogh P. Brandt Rehberg Shigeru Nishi J. Johnston A. C. Walker 《Analytical and bioanalytical chemistry》1928,75(1-2):39-46
27.
Delphine Margout Sharon Wein Hermine Gandon Florence Gattacceca Henri J. Vial Françoise M. M. Bressolle 《Journal of separation science》2009,32(11):1808-1815
1,12‐Bis[5‐(2‐hydroxyethyl)‐4‐methyl‐1,3‐thiazol‐3‐ium]dodecane dibromide (SAR97276, T3) is a new antimalarial drug, which is currently being evaluated in clinical trials for severe malaria. Drug accumulation inside the parasite and a dual mechanism of action are a major strength of this compound, as it could help delay the development of resistance. The purpose of this article was to develop a rapid resolution LC‐MS method for quantifying SAR97276 in mouse tissues. The LC system consisted of Zorbax Eclipse XDB C8 (1.8 μm, 50×4.6 mm, 60°C) column. Elution with a gradient mobile phase consisting of ACN–trimethylamine‐formate buffer (pH 3) at a flow rate of 1 mL/min yielded sharp, utmost‐resolved peaks within 2 min. Tissue samples were powdered under liquid nitrogen. After protein precipitation with citric acid, SPE using WCX cartridges was used for sample preparation. There was no influence of the matrix on the detection of either SAR97276 or the IS. Assay precision was <13% and accuracy was 90–107%. The lower LOQs were 3.3 μg/kg in brain and 33 μg/kg in liver and heart. This newly developed method was used to study the tissue distribution of SAR97276 in mouse as part of the ongoing development of SAR97276. 相似文献
28.
Alexandre Giuliani Isabelle Yao Bruno Lagarde Solenne Rey Jean‐Pierre Duval Patrick Rommeluere Frederic Jamme Valerie Rouam Frank Wein Carlos De Oliveira Manuel Ros Alain Lestrade Kewin Desjardins Jean‐Luc Giorgetta Olivier Laprevote Christian Herbaux Matthieu Refregiers 《Journal of synchrotron radiation》2011,18(4):546-549
In order to deliver VUV (vacuum ultraviolet) photons under atmospheric pressure conditions, a differential pumping system has been built on the DISCO beamline at the SOLEIL synchrotron radiation facility. The system is made of four stages and is 840 mm long. The conductance‐limiting body has been designed to allow practicable optical alignment. VUV transmission of the system was tested under air, nitrogen, argon and neon, and photons could be delivered down to 60 nm (20 eV). 相似文献
29.
30.
On the Energy Growth of Some Periodically Driven Quantum Systems with Shrinking Gaps in the Spectrum
We consider quantum Hamiltonians of the form H(t)=H+V(t) where the spectrum of H is semibounded and discrete, and the eigenvalues behave as E
n
∼n
α
, with 0<α<1. In particular, the gaps between successive eigenvalues decay as n
α−1. V(t) is supposed to be periodic, bounded, continuously differentiable in the strong sense and such that the matrix entries with
respect to the spectral decomposition of H obey the estimate ‖V(t)
m,n
‖≤ε|m−n|−p
max {m,n}−2γ
for m≠n, where ε>0, p≥1 and γ=(1−α)/2. We show that the energy diffusion exponent can be arbitrarily small provided p is sufficiently large and ε is small enough. More precisely, for any initial condition Ψ∈Dom(H
1/2), the diffusion of energy is bounded from above as 〈H〉
Ψ
(t)=O(t
σ
), where
. As an application we consider the Hamiltonian H(t)=|p|
α
+ε
v(θ,t) on L
2(S
1,dθ) which was discussed earlier in the literature by Howland. 相似文献