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981.
Thibaut Forestier Dr. Abdellah Kaiba Dr. Stanislav Pechev Dr. Dominique Denux Philippe Guionneau Dr. Céline Etrillard Nathalie Daro Eric Freysz Jean‐François Létard Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6122-6130
By changing the surfactant/water ratio , nanoparticles of the iron(II) spin crossover material, [Fe(NH2‐trz)3]Br2 ? 3 H2O (with NH2‐trz=4‐amino‐1,2,4‐triazole), have been synthesised from 1 μm down to 30 nm (see figure). Magnetic and reflectivity experiments indicate that the critical size for observing a thermal hysteresis in this 1D polymer family is around 50 nm, and powder X‐ray diffraction shows that particles of about 30 nm are constituted by about one coherent domain.
982.
1,2-Cyclic sulfite xylosides offer facile access to 1,2-oxazolines upon reaction with aromatic and alkyl nitriles under Lewis or Brönsted acid conditions. Additionally, hydrophobic ionic liquids facilitate acid-catalysed formations of such oxazolines and C- and O-linked xylosides, providing means to carry out fast reactions at room temperature, and this in yields comparable to reactions conducted in xylene at high temperature for extended reaction time. 相似文献
983.
Lars-Erik Briggner Rene Céolin Julien Giovannini Nathalie Payraudeau Ingemar Wads? 《Journal of Thermal Analysis and Calorimetry》2009,98(1):331-335
In many areas of scientific research and development, for example in the pharmaceutical industry, it is important to prepare
and to characterize crystals of pure organic compounds which are thermodynamically stable. The formation of crystals from
the gas phase is technically less straightforward than crystallisation from solution, but sublimation techniques can have
several important features. In the present paper we report the design and testing of a novel apparatus for small scale sublimation
and fractional deposition of crystals. The instrument has been developed with special reference to the needs in the pharmaceutical
industry. A few mg of the samples are enclosed, under reduced pressure, in thin-walled glass tubes, along which a well defined
temperature gradient can be formed. During an experiment the substance will sublime from the hot end of the glass tube and
crystals will be deposited along the temperature gradient. The applicability of the instrument has been verified by experiments
with several test compounds. Results from experiments with carbamazepine, are reported in some detail. Carbamazepine single
crystals of high quality were obtained and the transition temperature between the triclinic (Form I) and the monoclinic (Form
III) crystal modifications agreed with literature values. 相似文献
984.
Nathalie Lavignac Johanna L. Nicholls Paolo Ferruti Ruth Duncan 《Macromolecular bioscience》2009,9(5):480-487
Poly(amidoamine)s with amino pendant groups were prepared by hydrogen‐transfer polyaddition of primary and secondary amines to bis‐acrylamines. Dansyl cadaverine (DC) doxorubicin (Dox) were bound to the polymers via a cis‐aconityl spacer to give conjugates containing 3 µg of DC per mg of polymer and 28 to 35 µg of Dox per mg of polymer. Release of DC and Dox at physiological and acidic pH varied from 0 to 35% over 48 h and was pH dependent. Although the ISA1Dox conjugate (IC50 = 6 µg Dox · mL?1) presented similar toxicity as the parent polymer without Dox, ISA23Dox showed increased toxicity (IC50 = 10 µg Dox · mL?1). These results suggest that ISA23Dox is able to release biologically active Dox in vitro and that this conjugate might be suitable for further development.
985.
Maria G. E. G. Bremer Nathalie G. E. Smits Willem Haasnoot 《Analytical and bioanalytical chemistry》2009,395(1):119-126
The fraudulent addition of hazelnut oil to more expensive olive oil not only causes economical loss but may also result in
problems for allergic individuals as they may inadvertently be exposed to potentially allergenic hazelnut proteins. To improve
consumer safety, a rapid and sensitive direct biosensor immunoassay, based on a highly specific monoclonal antibody, was developed
to detect the presence of hazelnut proteins in olive oils. The sample preparation was easy (extraction with buffer); the assay
time was fast (4.5 min only) and the limit of detection was low (0.08 μg/g of hazelnut proteins in olive oil). Recoveries
obtained with an olive oil mixed with different amounts of a hazelnut protein containing hazelnut oil varied between 93% and
109%.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
986.
Jincai Wu Prof. Nathalie Dupont Shi‐Xia Liu Dr. Antonia Neels Dr. Andreas Hauser Prof. Silvio Decurtins Prof. 《化学:亚洲杂志》2009,4(3):392-399
CT or not CT : Three imidazole‐annulated TTF derivatives 1 – 3 have been prepared and fully characterized. The influence of the TTF unit on the pKa values of the acceptor units as determined by photometric titration has been discussed. The results reported here are part of an initial exploratory study to generate a range of well‐defined coordination networks.
987.
Elisabeth Gavilan Nathalie Audebrand 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(4):m156-m159
The structure of poly[[[hexaaquatrimanganese(II)]‐tri‐μ‐squarato] monohydrate], {[Mn3(C4O4)3(H2O)6]·H2O}n, synthesized hydrothermally, consists of a new three‐dimensional framework described by secondary building units (SBUs) containing two MnO6 octahedra and three squarate groups in a cube‐shaped arrangement. In the asymmetric unit, one squarate group is located around an inversion centre (4a; 0, 0, 0), two Mn atoms [4d (, , 0) and 4c (, , 0)] are located on inversion centres and the third Mn atom is on a twofold axis (4e; 0, y, ). This report illustrates the concept of the SBU and the flexibility of the squarate spacer in the design of new porous topologies. 相似文献
988.
Dupont N Ran YF Jia HP Grilj J Ding J Liu SX Decurtins S Hauser A 《Inorganic chemistry》2011,50(8):3295-3303
The synthesis and the photophysical properties of the complex [Ru(TTF-dppz)(2)(Aqphen)](2+) (TTF = tetrathiafulvalene, dppz = dipyrido-[3,2-a:2',3'-c]phenazine, Aqphen = anthraquinone fused to phenanthroline via a pyrazine bridge) are described. In this molecular triad excitation into the metal-ligand charge transfer bands results in the creation of a long-lived charge separated state with TTF acting as electron donor and anthraquinone as terminal acceptor. The lifetime of the charge-separated state is 400 ns in dichloromethane at room temperature. A mechanism for the charge separation involving an intermediate charge-separated state is proposed based on transient absorption spectroscopy. 相似文献
989.
The dehydration process of VOPO(4)·2H(2)O occurs in two steps corresponding to successive elimination of the two crystallographically distinct water molecules. The intermediate phase VOPO(4)·H(2)O has been stabilized for X-ray powder diffraction studies. The resulting data suggest a tetragonal cell (a = 6.2203(2) ? and c = 6.18867(7) ?), but an important anisotropy in the line broadening points out the necessity of considering a not perfectly organized structure. Because of the layered structure of this compound, density functional theory calculations including dispersion corrections have been carried out to evaluate the possible presence of stacking faults. The results of these calculations give information about the nature of the translations and their probabilities using a Boltzmann distribution. DIFFaX+ simulations of the X-ray powder diffraction pattern have been carried out using the results of the theoretical calculations and confirm the presence and nature of stacking faults. 相似文献
990.
Sutherland I Ignatova S Hewitson P Janaway L Wood P Edwards N Harris G Guzlek H Keay D Freebairn K Johns D Douillet N Thickitt C Vilminot E Mathews B 《Journal of chromatography. A》2011,1218(36):6114-6121
This paper addresses the technological readiness of counter-current chromatography (CCC) instruments to become platform technology for the pharmaceutical industry. It charts the development of the prototype technology since its inception in 1966, through conceptual improvements in the 1980s that led to higher speed separations in hours as opposed to days. It then describes the engineering improvements that have led to the development of high performance counter-current chromatography with the potential for scale-up to process scale for manufacturing products in industry with separation times in minutes rather than hours. A new UK Technology Strategy Board high value manufacturing £1.5 m research programme to take CCC through to technology readiness level 8 (i.e. as platform technology for continuous 24 × 7 operation by industry) is introduced. Four case studies are given as examples of successes from its expanding applications portfolio, which is mainly confidential. Finally, the hurdles for the uptake of new technology by industry are highlighted and the following potential solutions given: rapid method development, automation, continuous processing and instrument reliability and robustness. The future challenge for the CCC community will be to address these development needs urgently if CCC is to become the platform technology it deserves to be. 相似文献