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161.
162.
S. Munavalli R. K. Rohrbaugh G. W. Wagner H. D. Durst F. R. Longo 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1635-1643
Treatment of norbornene with trifluoromethylsulfenyl chloride at ?80°C furnishes, in addition to trifluoromethylthionortricyclane, four isomeric (chloro) (trifluoromethylthio)-norbornanes and bis-(2, 6-trifluoromethylthio)norbornane. The probable mechanism of the formation of the various compounds via free radical intermediates and their mass spectral characterization are described in this communication. 相似文献
163.
164.
Stacey M. Frumm Zi Peng Fan Kenneth N. Ross Jeremy R. Duvall Supriya Gupta Lynn VerPlank Byung-Chul Suh Edward Holson Florence F. Wagner William B. Smith Ronald M. Paranal Christopher F. Bassil Jun Qi Giovanni Roti Andrew L. Kung James E. Bradner Nicola Tolliday Kimberly Stegmaier 《Chemistry & biology》2013,20(5):713-725
165.
Noa Lachman Yifat Harel Adam Green Noa Iuster Jean‐Paul Lellouche H. Daniel Wagner 《Journal of Polymer Science.Polymer Physics》2012,50(14):957-962
In this article, Multi‐Walled Carbon Nanotubes (MWCNTs) of varying diameters, both untreated and polycarboxylated, were dispersed at constant weight percentage in an epoxy matrix, and resulting fracture toughnesses (KIc) were measured in each case. We show that changing the MWCNT diameter has two effects on the composite fracture toughness: (i) a small MWCNT diameter enables larger interfacial surface for adhesion maximization, which increases toughness; (ii) at the same time, it limits the available pull‐out energy and reduces the MWCNT ability to homogeneously disperse in the matrix due to this same large active surface: this decreases toughness. Most commercially available MWCNTs have a length range of several μm, thus an optimal diameter exists which depends on MWCNT wall thickness and surface treatment. Such optimal diameter maximizes pull‐out energy and thus composite fracture toughness. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
166.
Dr. James Biggs Dr. Karsten Danielmeier Dr. Julia Hitzbleck Dr. Jens Krause Tom Kridl Dr. Stephan Nowak Dr. Enrico Orselli Dr. Xina Quan Dirk Schapeler Will Sutherland Dr. Joachim Wagner 《Angewandte Chemie (International ed. in English)》2013,52(36):9409-9421
We present the development and applications of dielectric elastomers. For the last 10 years the significance of this class of polymers has risen as more applications seem possible and first products have been commercialized. 相似文献
167.
H. Daniel Wagner 《Journal of Macromolecular Science: Physics》2013,52(3-4):339-347
The axial and radial dimensions of a fiber are known to be key factors with respect to the mechanical stress necessary to promote failure, this being known as the size effect. Usually different methods are used to quantify the two types of size effects: Linear elastic fracture mechanics (lefm) and related schemes provide the theoretical basis for the effect of diameter variability upon strength whereas statistical theories, generally based upon the Weibull probability distribution combined with the weakest-link theorem, describe length effects. Here we show that simple modifications of the classical Poisson/Weibull form yield a new failure probability function which provides a more adequate explanation for diameter effects on strength in polydiacetylene fibers, and also resolves in a satisfactory way a current problematic issue inherent to the Weibull/weakest-link model. A maximum likelihood estimation procedure is presented for the evaluation of the most appropriate parameters of the proposed failure probability function. 相似文献
168.
169.
M. Kisielewicz J. Ciemniewski A. Wasiak K. Paprocki K. Kiszczak C. Wagner 《辐射效应与固体损伤》2013,168(5):157-161
Measurements of the depth profiles of disorder produced in silicon by argon ions implanted at energies of 20-300 keV and with a fluence of 1016 to 1017/cm2 were made by profiling the oxide growth rate. 相似文献
170.
Dr. Lukas Kaltschnee Dr. Anil P. Jagtap Dr. Jeffrey McCormick Dr. Shawn Wagner Prof. Dr. Louis-S. Bouchard Prof. Dr. Marcel Utz Prof. Dr. Christian Griesinger Dr. Stefan Glöggler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(47):11031-11035
NMR offers many possibilities in chemical analysis, structural investigations, and medical diagnostics. Although it is broadly used, one of NMR spectroscopies main drawbacks is low sensitivity. Hyperpolarization techniques enhance NMR signals by more than four orders of magnitude allowing the design of new contrast agents. Parahydrogen induced polarization that utilizes the para-hydrogen's singlet state to create enhanced signals is of particular interest since it allows to produce molecular imaging agents within seconds. Herein, we present a strategy for signal enhancement of the carbonyl 13C in amino acids by using parahydrogen, as demonstrated for glycine and alanine. Importantly, the hyperpolarization step is carried out in water and chemically unmodified canonical amino acids are obtained. Our approach thus offers a high degree of biocompatibility, which is crucial for further application. The rapid sample hyperpolarization (within seconds) may enable the continuous production of biologically useful probes, such as metabolic contrast agents or probes for structural biology. 相似文献