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81.
Reactions of triarylphosphines with fluoroantimony(III) triflates give phosphine antimony(III) complexes, which undergo spontaneous reductive elimination of fluorophosphonium cations. The resulting phosphine antimony(I) complexes catenate to give the first examples of cationic antimony bicyclic compounds, [(R3P)4Sb6]4+, featuring a bicyclo[3.1.0]hexastibine framework stabilized by four phosphine ligands. The unprecedented 14‐electron redox process illustrates the generality of the reductive catenation method.  相似文献   
82.
Metagenomic studies suggest that only a small fraction of the viruses that exist in nature have been identified and studied. Characterization of unknown viral genomes is hindered by the many genomes populating any virus sample. A new method is reported that integrates drop‐based microfluidics and computational analysis to enable the purification of any single viral species from a complex mixed virus sample and the retrieval of complete genome sequences. By using this platform, the genome sequence of a 5243 bp dsDNA virus that was spiked into wastewater was retrieved with greater than 96 % sequence coverage and more than 99.8 % sequence identity. This method holds great potential for virus discovery since it allows enrichment and sequencing of previously undescribed viruses as well as known viruses.  相似文献   
83.
Herein, we report a way to achieve abrupt high‐spin to low‐spin transition with controllable transition temperature and hysteresis width, relying not on solid‐state cooperative interactions, but utilizing coherency between phase and spin transitions in neutral FeII meltable complexes.  相似文献   
84.
The Group 18 elements (noble gases) were the last ones in the periodic system to have not been encountered in perovskite structures. We herein report the synthesis of a new group of double perovskites KM(XeNaO6) (M=Ca, Sr, Ba) containing framework‐forming xenon. The structures of the new compounds, like other double perovskites, are built up of the alternating sequence of corner‐sharing (XeO6) and (NaO6) octahedra arranged in a three‐dimensional rocksalt order. The fact that xenon can be incorporated into the perovskite structure provides new insights into the problem of Xe depletion in the atmosphere. Since octahedrally coordinated XeVIII and SiIV exhibit close values of ionic radii (0.48 and 0.40 Å, respectively), one could assume that XeVIII can be incorporated into hyperbaric frameworks such as MgSiO3 perovskite. The ability of Xe to form stable inorganic frameworks can further extend the rich and still enigmatic chemistry of this noble gas.  相似文献   
85.
The hemoglobin (Hb) released from erythrocytes is a primary nutritive component for many blood-feeding parasites. The aspartic protease cathepsin D is a hemoglobinase that is involved in the Hb degradation process and is considered an interesting target for chemotherapy intervention. However, traditional enzymatic assays for studying Hb degradation utilize spectrophotometric techniques, which do not allow real-time monitoring and can present serious interference problems. Herein, we describe a biosensor using simple approach for the real-time monitoring of Hb hydrolysis as well as an efficient screening method for natural products as enzymatic inhibitors using a quartz crystal microbalance (QCM) technique. Hemoglobin was anchored on the quartz crystal surface using mixed self-assembled monolayers. The addition of the enzyme caused a mass change (frequency shift) due to Hb hydrolysis, which was monitored in real time. From the frequency change patterns of the Hb-functionalized QCM, we evaluated the enzymatic reaction by determining the kinetic parameters of product formation (kcat). The QCM enzymatic assay using immobilized human Hb was shown to be an excellent approach for screening possible inhibitors in complex mixtures, opening up a new avenue for the discovery of novel inhibitors.  相似文献   
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