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1.
Natural phlogophite, pre-treated with acids and intercalated with alumina pillars, was used as catalytic support. Transition metals (Fe, Cu) were deposited on the surface of the modified clay materials by an ion-exchange method. The obtained samples were characterized with respect to structure (XRD), texture (BET), composition (EPMA) and chemical nature of the deposited transition metals species (UV-vis-DRS). The phlogophite based materials have been found to be active and selective catalysts of the DeNOx process. The Fe-containing samples were catalytically active at lower temperatures than the clays modified with copper. A competitive ammonia oxidation by oxygen decreased the effectiveness of the DeNOx process in the high temperature range.  相似文献   
2.
    
The reaction of CCl2F2 (CFC 12) with hydrogen has been studied on a Pt/-Al2O3 catalyst containing 0.5, 2 and 5 wt % of Pt at a temperature of 300°C and on 2% Pt at other temperatures. The product selectivity (distribution), and the extent of conversion, was shown to be highly dependent both on the metal coverage and on the temperature.  相似文献   
3.
We construct an example of a combinatorially large measure-zero set.  相似文献   
4.
The CDK4/6 inhibitor palbociclib, combined with endocrine therapy, has been shown to be effective in postmenopausal women with estrogen receptor-positive, HER2-negative advanced or metastatic breast cancer. However, palbociclib is not as effective in the highly aggressive, triple-negative breast cancer that lacks sensitivity to chemotherapy or endocrine therapy. We hypothesized that conjugation of the near-infrared dye MHI-148 with palbociclib can produce a potential theranostic in triple-negative, as well as estrogen receptor-positive, breast cancer cells. In our study, the conjugate was found to have enhanced activity in all mammalian cell lines tested in vitro. However, the conjugate was cytotoxic and did not induce G1 cell cycle arrest in breast cancer cells, suggesting its mechanism of action differs from the parent compound palbociclib. The study highlights the importance of investigating the mechanism of conjugates of near-infrared dyes to therapeutic compounds, as conjugation can potentially result in a change of mechanism or target, with an enhanced cytotoxic effect in this case.  相似文献   
5.
We will construct several models where there are no strongly meager sets of size 20. First author partially supported by NSF grant DMS 0200671.Second author partially supported by Israel Science Foundation and NSF grant DMS 0072560. Publication 807. Mathematics Subject Classification (2000):03E15, 03E20  相似文献   
6.
The adsorption of a C60 monolayer on a graphite substrate was modelled via molecular dynamics simulation covering a significant period of 160 picoseconds. The final configuration of C60s agrees closely with that observed in a scanning tunnelling microscopy (STM) experiment. Clusters of adsorbed molecules were then selected and their STM-like images were computed via the Keldysh Green function method. Presented at the VIII-th Symposium on Surface Physics, Třešt’ Castle, Czech Republic, June 28 – July 2, 1999.  相似文献   
7.
Prosomes, cytoplasmatic ribonucleoprotein complexes containing small ribonucleic acid (19S small cytoplasmic RNPs), are ubiquitous in eukaryotic organisms. A new method for the preparation of prosomes in large amounts, starting with ca. 2 kg of calf's liver, is described. A combination of centrifugation and low- and high-pressure chromatography was used to purify intact particles. An alternative purification of prosomes with Solanum tuberosum agglutinin bound to divinyl sulphone-activated agarose is discussed. Calf's liver prosomes have a similar protein composition and RNA content to prosomes isolated from other tissues.  相似文献   
8.
We present a successful attempt of decoupling a dye molecule from a metallic surface via physisorption for enabling direct photoisomerization. Effective switching between the isomers is possible by exposure to UV light via the rotation pathway.  相似文献   
9.
We show that it is consistent with MA + ?CH that the Forcing Axiom fails for all forcing notions in the class of ωω–bounding forcing notions with norms of [17]. Received: 28 April 1999 / Published online: 12 December 2001  相似文献   
10.
We show that it is consistent with ZFC that the intersection of some family of less than ultrafilters have measure zero. This answers a question of D. Fremlin.The author thanks the Lady Davis Fellowship Trust for full supportPartially supported by Basic Research Fund, Israel Academy of Sciences, publication 436  相似文献   
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