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41.
42.
Ludwig Maier Guenter Rist Peter J. Lea 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):349-352
Abstract The synthesis and properties of phosphinothricin derivatives which have different alkyl groups attached to phosphorus or bear a substituent on the nitrogen are described and their biological activities discussed. 相似文献
43.
Immunoassays are a proven approach towards fast, sensitive, cost-effective and easy-to-use analytical systems which are able
to measure a variety of interesting analytes, especially in medical diagnostics. Herein, we report two assay formats, binding
inhibition and sandwich assay format, for detection of C-reactive protein (CRP) in human serum. Both assays were characterised
and compared with respect to their suitability and adaption into a complete sensor system. An automated, optical biosensor
system, based on evanescent field technology, was used to carry out a full threefold calibration in each case. Owing to the
resulting working ranges, 0.044–2.9 mg L−1 and 0.13–22.9 mg L−1, respectively, the assays qualify for use in detecting high-sensitivity CRP (C-reactive protein). 相似文献
44.
Audrey Di Martino Jean‐Pierre Broyer Daniel Schweich Claude de Bellefon Guenter Weickert Timothy F. L. McKenna 《大分子反应工程》2007,1(2):284-294
A novel stopped flow reactor system is described in the current work, along with the underlying design philosophy. While the concept of stopped flow technology is not recent, this system is the first to be designed with the objective of studying particle morphology, and to work at extremely short (40 ms) residence times. It is shown that traditional chemical engineering principles are required to properly design and operate this type of reactor, and that when correctly design, it is a very flexible tool for the study of nascent polymerisation of olefins.
45.
J Trzaskowski C Rabe K Vogtt M Krumova G Goerigk M Ballauff S Mecking 《Chemical communications (Cambridge, England)》2012,48(73):9153-9155
Nanoparticles of precisely branched polyethylenes possess a distinct oblate shape resulting from a crystalline lamella in the particle as revealed by SAXS and TEM, and display controllable and well-behaved thermal behaviour. 相似文献
46.
Measurements of the Nusselt number Nu and of a Reynolds number Re(eff) for Rayleigh-Bénard convection (RBC) over the Rayleigh-number range 10(12)?Ra?10(15) and for Prandtl numbers Pr near 0.8 are presented. The aspect ratio Γ≡D/L of a cylindrical sample was 0.50. For Ra?10(13) the data yielded Nu∝Ra(γ(eff)) with γ(eff)?0.31 and Re(eff)∝Ra(ζ(eff)) with ζ(eff)?0.43, consistent with classical turbulent RBC. After a transition region for 10(13)?Ra?5×10(14), where multistability occurred, we found γ(eff)?0.38 and ζ(eff)=ζ?0.50, in agreement with the results of Grossmann and Lohse for the large-Ra asymptotic state with turbulent boundary layers which was first predicted by Kraichnan. 相似文献
47.
Nair V Sethumadhavan D Nair SM Rath NP Eigendorf GK 《The Journal of organic chemistry》2002,67(21):7533-7536
Highly substituted tropone derivatives were obtained as a result of SnCl4-catalyzed cycloaddition of 3-methoxy-substituted o-benzoquinones with aryl acetylenes and subsequent rearrangement of the adducts with concomitant decarbonylation. 相似文献
48.
A method is described for the determination of the total nitrogen content, after conversion to nitrogen gas, of various types of samples before the mass-spectrometric analysis of the 15N abundance. The sample is burned with a mixture of copper oxide, copper and lime in a closed tube under vacuum (modified Dumas method). The gas is released into an evacuated chamber of known volume and the nitrogen pressure is used to determine the nitrogen content of the sample. The gas is then admitted into a mass spectrometer. In order to obtain complete combustion of the material and to generate pure nitrogen gas, various combustion temperatures, combustion times and oxidizing agents were compared. 相似文献
49.
Kalyanasundaram Seshadri Norbert Peters Forman A. Williams Vedha Nayagam Guenter Paczko 《Combustion Theory and Modelling》2016,20(6):1118-1130
A skeletal chemical-kinetic mechanism for n-heptane cool flames is simplified to the maximum extent possible by introduction of steady-state approximations for intermediaries, following procedures employed previously in addressing two-stage ignition. A pair of ordinary differential equations in mixture-fraction space is thereby obtained, describing the quasi-steady structures of the temperature and heptylketohydroperoxide fields. Application of activation-energy asymptotics for the partial-burning regime to this pair of equations is shown to provide convenient expressions for flame structures and the extinction condition associated with maximally reduced chemistry. With the mixture-fraction co-ordinate related to radius, these results are used to address droplet-combustion experiments that have been performed in the International Space Station. Droplet diameters at extinction are predicted as functions of the oxygen concentration in the atmosphere and are compared with experiment. While the results are encouraging concerning qualitative predictions of dependences of extinction diameters on atmospheric conditions, there are noticeable quantitative differences that point to deficiencies in the analysis, likely resulting from a number of oversimplifications. Further investigation is therefore recommended. 相似文献
50.