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Two lipid binders, glyceryl behenate and paraffin wax, were examined regarding their ability to be used in a prilling process. Prilling has the advantage to produce microgranules very reproducible in size and shape but involves ultrafast cooling of liquid droplets. The different steps to produce solid micropheres from the molten state were successfully modelled to predict crystallisation time as a function of the binder used. Bulk versus microgranules characterization by differential scanning calorimetry, X-ray diffraction and microscopies showed the peculiar suitability of the 50/50 mixture of the two lipid binders for prilling, in agreement with the theoretical approach.  相似文献   
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The French Food Safety Agency is a public body incorporating 12 laboratories that perform research to support expertise and public decisions taken in the fields of sanitary safety of food, animal health, and veterinary drugs. On the request of the General Management of the Agency a quality-management system in research (QMSR) is being implemented in the Food and Food Process Quality Research Laboratory. The experimental QMSR is based on existing standards and documents, describing the provisions required for scientific and technical competence, quality management, and project management. Furthermore, this QMSR also incorporates specific notions of great importance for research activities such as the positive and negative non-conformities, the non-confirmation of hypotheses, and the principle of evaluation of a research activity by peers for both quality and scientific aspects.  相似文献   
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Corrigendum     
Reactions of NaMn(CO)3 with RuCl2(PMe3)4, RuCl2(dppm)2 and RuCl2(PPh3)3 lead either to an ionic species [Ru2Cl3(PMe3)6]+[Mn(CO)5]? or to metal—metal bonded RuMn compounds such as RuMn(μ-CO)2(CO)3(μ-dppm)2 Cl, and, quite unexpectedly, to the μ-phosphido complex RuMn(μ-PPh2)(CO)6(PPh3)2 via a hydride intermediate.  相似文献   
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Two novel 5(20)-thia analogues of docetaxel have been synthesized from 10-deacetylbaccatin III or taxine B and isotaxine B. The key step of these syntheses is the concomitant thietane ring formation and acetylation of the tertiary alcohol at C-4. Both compounds are less cytotoxic than docetaxel but have divergent activity on microtubule disassembly.  相似文献   
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[structure: see text] A solid-phase fluorenylmethyloxycarbonyl (Fmoc)-based synthesis strategy is described for "mixed" aza-beta3-peptides as well as a convenient general approach for their required building blocks, the aza-beta3-amino acid residues (aza-beta3-aa). These monomers allow the synthesis of relatively large quantities of pure mixed aza-beta3-peptides. The required Fmoc-substituted aza-beta3-amino acids are accessible by convenient synthesis, and a number of monomers including those containing side chains with functional groups have been synthesized. The method was applied toward the solid-phase synthesis of aza-beta3-peptide mimetics of a biologically active histone H4 sequence.  相似文献   
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Metal phosphine hydrides of type RuP(4)H(2) and RhP(3)H(3) react photochemically with HB(pin)(pin = pinacolate) to form metal boryl hydride complexes via 16-electron intermediates generated by H(2) loss; the second order rate constants for reaction of the intermediates with HB(pin) are even larger than those for reaction with Et(3)SiH.  相似文献   
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[reaction: see text] A convergent method has been found to prepare 4-aza-2,3-didehydropodophyllotoxin and derivatives in a one-pot procedure. The mechanism of the reaction between tetronic acid, anilines, and benzaldehydes is discussed.  相似文献   
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