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81.
B. Lind C. -G. Elinder L. Friberg B. Nilsson M. Svartengren M. Vahter 《Fresenius' Journal of Analytical Chemistry》1987,326(7):647-655
Summary An extensive quality control programme has been developed within a global UNEP/WHO project on Assessment of Exposure to Lead and Cadmium through Biological Monitoring. This project was coordinated by the Karolinska Institute (Department of Environmental Hygiene) and the National (Swedish) Institute of Environmental Medicine. The project was carried out within the framework of UNEP's Global Environmental Monitoring System (GEMS) and was initiated in 1978 on the basis of recommendations from a UNEP/WHO meeting of a Government Expert Group on Health-Related Monitoring.On termination of the project in 1981 it was decided to extend the analytical QC assurance programme on a periodic basis in order to maintain the analytical capability of the participating laboratories. A QC programme was conducted by our Institute in a follow-up study of the above mentioned UNEP/WHO programme and for a National Swedish Board of Occupational Safety and Health project, as well as for a recently concluded project in which a decrease in bloodlead levels in residents of Stockholm for the period 1980–1984 was established.In the latter project decreased blood-lead levels of about 20% were found in samples stored frozen (–20 ° C) for 4 years. This finding stimulated a study of the long-term stability of our QC samples. Results of lead and cadmium analyses performed for each QC sample during 1980–1985 were computerized. The results showed that the QC samples appeared to be stable for 2–3 years when stored at –20 °C. The losses of cadmium were 5 –10% in 5–6 years of storage at –20 ° C and seem to be less than those of lead (7–15%). Analysis of several QC sets, prepared on different occasions, but analyzed on the same day, confirmed that losses occur. 相似文献
82.
Maxwell D. Cummings Jimmy Lindberg Tse‐I Lin Herman de Kock Oliver Lenz Elisabet Lilja Sara Felländer Vera Baraznenok Susanne Nyström Magnus Nilsson Lotta Vrang Michael Edlund Åsa Rosenquist Bertil Samuelsson Pierre Raboisson Kenneth Simmen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2010,122(19):3320-3320
83.
Andrei Yu. Khrennikov Marcus Nilsson 《Proceedings of the Steklov Institute of Mathematics》2009,265(1):140-142
We discuss the similarity of the degeneration structure of the genetic code with a purely number theoretic “divisors code.”
The most interesting thing about our observation is not that there is a connection between number theory and the genetic code,
but the simplicity of the rule. We hope that the observation and the naive model presented in this paper will spur ideas for
other models of the degeneracy of the genetic code. Maybe, the ideas of this article can also be used in the area of artificial
life to synthesize artificial genetic codes. 相似文献
84.
E. J. K. Nilsson M. S. Johnson O. J. Nielsen E. W. Kaiser T. J. Wallington 《国际化学动力学杂志》2009,41(6):401-406
Relative rate techniques were used to study the title reactions in 930–1200 mbar of N2 diluent. The reaction rate coefficients measured in the present work are summarized by the expressions k(Cl + CH2F2) = 1.19 × 10?17 T2 exp(?1023/T) cm3 molecule?1 s?1 (253–553 K), k(Cl + CH3CCl3) = 2.41 × 10?12 exp(?1630/T) cm3 molecule?1 s?1 (253–313 K), and k(Cl + CF3CFH2) = 1.27 × 10?12 exp(?2019/T) cm3 molecule?1 s?1 (253–313 K). Results are discussed with respect to the literature data. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 401–406, 2009 相似文献
85.
86.
Camilla Nilsson Eva Malmström Mats Johansson Stacy M. Trey 《Journal of polymer science. Part A, Polymer chemistry》2009,47(2):589-601
A series of well‐defined allyl‐ether functionalized polyester dendrimers has been synthesized via the divergent approach using traditional esterification reactions. Two commercially available trifunctional thiols, trimethylolpropane tri(3‐mercaptopropanoate) (TRIS) and ethoxylated trimethylolpropane tri(3‐mercaptopropanoate) (ETTMP), were incorporated with the dendrimers into the thiol‐ene polymer networks. The thiol‐ene reactions were conducted at room temperature and cured by UV light without the addition of photoinitiatior. Highly crosslinked films were obtained and characterized with respect to mechanical (DMA) and thermal (DSC and TGA) properties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 589–601, 2009 相似文献
87.
Camilla Nilsson Neil Simpson Michael Malkoch Mats Johansson Eva Malmström 《Journal of polymer science. Part A, Polymer chemistry》2008,46(4):1339-1348
Well‐defined, allyl‐ether functional, first‐generation dendrimers have been synthesized. The convergent growth approach was utilized, using the anhydride of the allyl‐ether terminated building block. Three different core moieties were used: trimethylolpropane, trisphenol, and ditrimethylolpropane. The coupling reactions proceeded in good yields and all compounds were characterized by NMR, MALDI‐TOF, and SEC. The allyl‐terminated dendrimers were crosslinked by thiol–ene chemistry, using a multifunctional thiol, TriThiol, to give clear and smooth films. The photopolymerization was conducted in the presence of a photoinitiator, Irgacure 651, and no traces of either allyl‐ether groups or thiols were observed by FT‐Raman after cure. All crosslinked films were characterized with respect to mechanical (DMA) and thermal (DSC) properties. It was found that homogeneous networks were formed and that the core functionality and structure had little effect on the network properties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1339–1348, 2008 相似文献
88.
D. Nilsson J. -O. Adler B. -E. Andersson K. I. Blomqvist L. Isaksson A. Sandell B. Schröder K. Ziakas L. Van Hoorebeke D. Ryckbosch R. Van de Vyver 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(2):239-240
The high spin structure of the nucleus129Ba has been investigated using a18O induced reaction. The known bands could be followed up to a maximum spin (55/2) ?. Some 56 states and 78 transitions could be placed in the level scheme. Band crossings were established in both positive and negative parity structures. They display features of strong polarization effects due to the alignment of h11/2 protons. 相似文献
89.
Huang C Weiss TM Nordlund D Wikfeldt KT Pettersson LG Nilsson A 《The Journal of chemical physics》2010,133(13):134504
Using small angle x-ray scattering, we find that the correlation length of bulk liquid water shows a steep increase as temperature decreases at subzero temperatures (supercooling) and that it can, similar to the thermodynamic response functions, be fitted to a power law. This indicates that the anomalous properties of water are attributable to fluctuations between low- and high-density regions with rapidly growing average size upon supercooling. The substitution of H(2)O with D(2)O, as well as the addition of NaCl salt, leads to substantial changes of the power law behavior of the correlation length. Our results are consistent with the proposed existence of a liquid-liquid critical point in the deeply supercooled region but do not exclude a singularity-free model. 相似文献
90.
Miller DJ Öberg H Kaya S Sanchez Casalongue H Friebel D Anniyev T Ogasawara H Bluhm H Pettersson LG Nilsson A 《Physical review letters》2011,107(19):195502
The oxidation of Pt(111) at near-ambient O2 pressures has been followed in situ using x-ray photoelectron spectroscopy (XPS) and ex situ using x-ray absorption spectroscopy (XAS). Polarization-dependent XAS signatures at the O K edge reveal significant temperature- and pressure-dependent changes of the Pt-O interaction. Oxide growth commences via a PtO-like surface oxide that coexists with chemisorbed oxygen, while an ultrathin α-PtO2 trilayer is identified as the precursor to bulk oxidation. These results have important implications for understanding the chemical state of Pt in catalysis. 相似文献