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1.
J.-C. Thomas L. Achouri J. Äystö R. Béraud B. Blank G. Canchel S. Czajkowski P. Dendooven A. Ensallem J. Giovinazzo N. Guillet J. Honkanen A. Jokinen A. Laird M. Lewitowicz C. Longour F. de Oliveira Santos K. Peräjärvi M. Stanoiu 《The European Physical Journal A - Hadrons and Nuclei》2004,21(3):419-435
2.
Martin E. V. Pedersen Lars S. Rishøj Henrik Steffensen Sanshui Xiao Niels Asger Mortensen 《Optical and Quantum Electronics》2007,39(10-11):903-911
Slow-light enhanced optical detection in liquid-infiltrated photonic crystals is theoretically studied. Using a scattering-matrix approach and the Wigner–Smith delay time concept, we show that optical absorbance benefits both from slow-light phenomena as well as a high filling factor of the energy residing in the liquid. Utilizing strongly dispersive photonic crystal structures, we numerically demonstrate how liquid-infiltrated photonic crystals facilitate enhanced light–matter interactions, by potentially up to an order of magnitude. The proposed concept provides strong opportunities for improving existing miniaturized absorbance cells for optical detection in lab-on-a-chip systems. 相似文献
3.
Summary A method is described for the determination of small quantities of hydrochloric acid in two chlorinated organic solvents (CHCl3 and CCl4). An excess of gaseous ethylene oxide is added to a liquid sample; the 2-chloroethanol formed is then analyzed by gas chromatography. The procedure is simpler and more sensitive in comparison with other conventional methods. It can be modified for other organic solvents.D.G.R.C.S.T. grant. 相似文献
4.
The 18-methylene-1,2-dehydroaspidospermidine (III) was stereospecifically transformed into the schizozygane alkaloid strempeliopine (II) in 16,6 % overall yield. 相似文献
5.
Joseph H. Montoya Kirsten T. Winther Raul A. Flores Thomas Bligaard Jens S. Hummelshj Muratahan Aykol 《Chemical science》2020,11(32):8517
We present an end-to-end computational system for autonomous materials discovery. The system aims for cost-effective optimization in large, high-dimensional search spaces of materials by adopting a sequential, agent-based approach to deciding which experiments to carry out. In choosing next experiments, agents can make use of past knowledge, surrogate models, logic, thermodynamic or other physical constructs, heuristic rules, and different exploration–exploitation strategies. We show a series of examples for (i) how the discovery campaigns for finding materials satisfying a relative stability objective can be simulated to design new agents, and (ii) how those agents can be deployed in real discovery campaigns to control experiments run externally, such as the cloud-based density functional theory simulations in this work. In a sample set of 16 campaigns covering a range of binary and ternary chemistries including metal oxides, phosphides, sulfides and alloys, this autonomous platform found 383 new stable or nearly stable materials with no intervention by the researchers.We present an end-to-end computational system for autonomous materials discovery. 相似文献
6.
Hydroxyapatite-poly(d,l-lactide) Nanografts. Synthesis and Characterization as Bone Cement Additives
Kristina L. Goranova Anne Kathrine Kattenhj Sloth Overgaard Ivan Gitsov 《Molecules (Basel, Switzerland)》2021,26(2)
This paper reports the creation of hydroxyapatite/polyester nanografts by “graft-from” polymerization of d,l-lactide with [Ca5(OH)(PO4)3]2 as the initiator and tin(II)-2-ethylhexanoate as the catalyst. Model polymerizations were performed with cyclooctanol as initiator to confirm the grafting on the surface of the hydroxyapatite nanocrystals. Polymers with the highest molecular mass (Mn) between 4250 Da (cyclooctanol) and 6100 Da (hydroxyapatite) were produced. In both cases the molecular mass distributions of the polymers formed were monomodal. The materials obtained were characterized by size-exclusion chromatography, NMR and FT-IR spectroscopy, and thermal methods. Their suitability as additives for commercial bone cement (Simplex P Speedset, Stryker Orthopaedics) has been confirmed by thermal analysis techniques and mechanical testing. The results obtained show that addition of the hydroxyapatite/ polyester nanografts improved both thermal and mechanical properties of the bone cement. 相似文献
7.
H.?J.?M.?BouwmeesterEmail author M.?W.?Den?Otter B.?A.?Boukamp 《Journal of Solid State Electrochemistry》2004,8(9):599-605
The surface exchange coefficient and chemical diffusion coefficient of oxygen for the perovskites La0.6Sr0.4Co1–yFeyO3–jq1hxujr/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0"> (y=0.2, 0.5 and 0.8) were measured using the conductivity relaxation technique. Measurements were performed between 600 and 800 °C in an oxygen partial pressure range between 10–4 and 1 bar. Both transport coefficients decrease markedly with decreasing oxygen partial pressure below about 10–2 bar at all temperatures. This is attributed to ordering of oxygen vacancies. Implications for using La0.6Sr0.4Co1–yFeyO3–jq1hxujr/xxlarge948.gif" alt="delta" align="BASELINE" BORDER="0"> as an oxygen separation membrane are discussed.Presented at the OSSEP Workshop jq1hxujr/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">Ionic and Mixed Conductors: Methods and Processesjq1hxujr/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0">, Aveiro, Portugal, 10-12 April 2003 相似文献
8.
P. Hájíček 《Foundations of Physics》2012,42(4):555-581
In our previous work, a new approach to the notorious problem of quantum measurement was proposed. Existing treatments of
the problem were incorrect because they ignored the disturbance of measurement by identical particles and standard quantum
mechanics had to be modified to obey the cluster separability principle. The key tool was the notion of separation status.
Changes of separation status occur during preparations, registrations and scattering on macroscopic targets. Standard quantum
mechanics does not provide any correct rules that would govern these changes. This gives us the possibility to add new rules
to quantum mechanics that would satisfy the objectification requirement. The method of the present paper is to start from
the standard unitary evolution and then introduce minimal corrections. Several representative examples of registration and
particle scattering on macroscopic targets are analysed case by case in order to see their common features. The resulting
general Rule of Separation Status Changes is stated in the Conclusion. 相似文献
9.
10.
H. Penttilä D. Gorelov V. -V. Elomaa T. Eronen U. Hager J. Hakala A. Jokinen A. Kankainen P. Karvonen I. D. Moore J. Parkkonen K. Peräjärvi I. Pohjalainen S. Rahaman S. Rinta-Antila J. Rissanen V. A. Rubchenya A. Saastamoinen V. Simutkin T. Sonoda C. Weber A. Voss J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2016,52(4):104