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排序方式: 共有651条查询结果,搜索用时 15 毫秒
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PREPARATION AND PROPERTIES OF CLAY/POLY(N-ISOPROPYLACRYLAMIDE-co-ACRYL AMIDE)NANOCOMPOSITE HYDROGELS
LIU Xiaoli LIU Yang Zhang WEI JIANG Yongmei GU Chunju ZHU Meifang** Adler H.J. .State Key Lab for Modification of Polymer Materials Chemical Fibers College of Material Sci.& Eng. Donghua University Shanghai China .Institute of Macromolecular Chemistry Textile Chemistry Dresden University of Technology Mommsenstr. D- Dresden Germany 《Chinese Journal of Reactive Polymers》2006,(1)
Polymer hydrogels as a kind of soft materials have attracted increasing scientific and technological interest in past several decades. These materials have been applied widely in many fields [1], such as molecular filter [2,3], superabsorbent [4], and contact lenses [5] etc. However, synthetic polymeric hydrogels are seldom used as mechanical devices due to the lack of mechanical strength. Therefore, it is very imperative to improve their mechanical properties for wider use of polymeric hydrog… 相似文献
14.
In the anionic polymerization of polar monomers the nature of active centres is considerably influenced by the reaction conditions. In a survey, the present state of knowledge is represented and discussed for the polymerization of acrylonitrile. Analogous problems of methyl methacrylate and vinylpyridine polymerization are included in the considerations. 相似文献
15.
Stephen L. Adler 《Foundations of Physics》2018,48(11):1557-1567
We review the argument that latent image formation is a measurement in which the state vector collapses, requiring an enhanced noise parameter in objective reduction models. Tentative observation of a residual noise at this level, plus several experimental bounds, imply that the noise must be colored (i.e., non-white), and hence frame dependent and non-relativistic. Thus a relativistic objective reduction model, even if achievable in principle, would be incompatible with experiment; the best one can do is the non-relativistic CSL model. This negative conclusion has a positive aspect, in that the non-relativistic CSL reduction model evades the argument leading to the Conway–Kochen “Free Will Theorem”. 相似文献
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Adler J Becker JJ Blaylock GT Bolton T Brient J Browder T Brown JS Bunnell KO Burchell M Burnett TH Cassell RE Coffman D Cook V Coward DH DeJongh F Dorfan DE Drinkard J Dubois GP Eigen G Einsweiler KF Eisenstein BI Freese T Gatto C Gladding G Grab C Hamilton RP Hauser J Heusch CA Hitlin DG Izen JM Kim PC Köpke L Li A Lockman WS Mallik U Matthews CG Mincer AI Mir R Mockett PM Mozley RF Nemati B Odian A Parrish L Partridge R Pitman D Plaetzer SA Richman JD Sadrozinski HF Scarlatella M Schalk TL 《Physical review letters》1989,62(16):1821-1824
18.
André Adler 《Journal of Theoretical Probability》2002,15(4):939-949
Consider independent and identically distributed random variables {X,X
nj
, 1jn,n1} with density f(x)=px
–p–1
I(x1), where p>0. We show that there exist unusual generalized Laws of the Iterated Logarithm involving the larger order statistics from our array. 相似文献
19.
Schmitt-Jansen M Bartels P Adler N Altenburger R 《Analytical and bioanalytical chemistry》2007,387(4):1389-1396
The occurrence of pharmaceuticals in the environment is an emerging issue. Several studies observed that the non-steroidal
anti-inflammatory drug diclofenac is ubiquitously present in most of the surveyed surface waters, worldwide. Phototransformation
of diclofenac was reported from laboratory assays as well as in natural water systems, raising the question of possible adverse
effects of the phototransformation products of diclofenac to aquatic organisms. In this study the phytotoxicity of diclofenac
exposed to natural sunlight was evaluated using synchronized cultures of the unicellular chlorophyte Scenedesmus vacuolatus. Diclofenac dissolved in ultra-pure water at 50 mg L−1 was exposed to natural midsummer sunlight for a maximum of 145 h. Twice a day subsamples were taken for chromatography and
parallel phytotoxicity assessment. Inhibition of algal reproduction of the initial diclofenac solution was in the mg L−1 range indicating no specific toxicity of diclofenac towards S. vacuolatus. Fast degradation of diclofenac was observed with half lives between 3.3 and 6.4 h during the first and the third day of
exposure, respectively. Phytotoxicity increased after 3.5 h of exposure of diclofenac to sunlight and showed a maximum of
sixfold enhanced toxicity after 53 h of exposure to sunlight. Several phototransformation products were found during the experiment.
The time courses of the relative concentration of three transformation products significantly correlated with enhanced phytotoxicity
during the experiment. This indicates a high toxicity potential of phototransformation products of diclofenac at concentration
levels that may come close to environmental concentrations of residual diclofenac after degradation. We conclude that toxicity
assessment of phototransformation products should be included in the risk assessment of pharmaceuticals in the environment. 相似文献
20.
Xinyi. Cai Dr. Alessandra Lucini Paioni Agnes Adler Ru Yao Wenxiao Zhang David Beriashvili Adil Safeer Andrei Gurinov Prof. Antal Rockenbauer Prof. Dr. Yuguang Song Prof. Dr. Marc Baldus Prof. Dr. Yangping Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(50):12758-12762
Dynamic nuclear polarization (DNP) is a powerful method to enhance the sensitivity of solid-state magnetic nuclear resonance (ssNMR) spectroscopy. However, its biomolecular applications at high magnetic fields (preferably>14 T) have so far been limited by the intrinsically low efficiency of polarizing agents and sample preparation aspects. Herein, we report a new class of trityl-nitroxide biradicals, dubbed SNAPols that combine high DNP efficiency with greatly enhanced hydrophilicity. SNAPol-1, the best compound in the series, shows DNP enhancement factors at 18.8 T of more than 100 in small molecules and globular proteins and also exhibits strong DNP enhancements in membrane proteins and cellular preparations. By integrating optimal sensitivity and high resolution, we expect widespread applications of this new polarizing agent in high-field DNP/ssNMR spectroscopy, especially for complex biomolecules. 相似文献