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51.
Michael I. Bruce Natasha N. Zaitseva Brian W. Skelton Allan H. White 《Journal of Cluster Science》1996,7(2):109-119
The reaction between Ru3(3-2-PhC2C=CPh)(-dppm)(CO)8 and Co2(CO)8 afforded dark red Co2Ru3(4-C2Ph)(3-C2Ph)(-dppm)(-CO)2(CO)9, shown by an X-ray structure determination to contain a strongly twisted Co2Ru3 bow-tie cluster (central Co), to which two PhC2 units derived from cleavage of the original diyne are attached. One a these is strongly interacting with four metal atoms, the other being attached in the familiar 1,22-mode. The dppm ligand remains bridging two of the Ru atoms. 相似文献
52.
Antonova AB Bruce MI Ellis BG Gaudio M Humphrey PA Jevric M Melino G Nicholson BK Perkins GJ Skelton BW Stapleton B White AH Zaitseva NN 《Chemical communications (Cambridge, England)》2004,(8):960-961
Elimination of AuX(PR3)(X = halogen, R = Ph, tol) occurs readily in reactions between compounds containing C(sp)- or C(sp2)-X bonds and alkynyl or polyynyl gold(I) complexes; this reaction has been applied to the syntheses of complexes containing a variety of metal centres linked by C(n) chains (n up to 16). 相似文献
53.
Michael I. Bruce Brian W. Skelton Allan H. White Natasha N. Zaitseva 《Journal of Cluster Science》2002,13(2):235-247
Thermolysis of Ru3 cluster complexes containing diarylallenylidene and dppm ligands results in phenyl migration from dppm to the allenylidene with concomitant H migration and C–C bond formation reactions to give several complexes each containing a cluster-bound indenyl group. In initially-formed complexes 3 or 6, the diarylindenyl group is attached to the cluster by two localized C=C double bonds of one aryl group and a benzylic interaction of the remaining C=C double bond combined with one carbon of the five-membered ring. Thermal rearrangement of these complexes with concomitant loss of CO gives 4 or 7, respectively, in which the indenyl group is more symmetrically bonded to the cluster by two C=C double bonds from the six-membered ring and an
5-interaction from the five-membered ring, both of the indenyl ligand. The X-ray crystal structure determination of Ru3(
3-PPhCH2PPh2)(
3-C9H5Ph2)(CO)5 (4) is reported. A related reaction was found between Ru3(-H)(-CCCPh2)(-OH)(CO)9 and Co2(CO)8, which afforded CoRu3(
3-C9H6Ph) (-CO)4(CO)5 (8), also structurally characterized, in which the indenyl group caps the Ru3 face of a CoRu3 tetrahedron; unusually, there are four CO groups bridging the three Co–Ru bonds. 相似文献
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The enormous potential of biosensors in medical diagnostics has motivated scientists to develop newer innovative tools and advance biosensing technologies. The use of cell, organelles, nucleotides, aptamers, antibodies, affibodies, proteins, peptides, molecules, and printed polymers, merged with nanotechnology, offers excellent tools to prepare highly sensitive and advanced biosensors. Therefore, the current decade has witnessed a rapid surge in the fabrication of different nanomaterial-based biosensors. Among them, carbon nanomaterials (CNMs) have emerged highly attractive in the fabrication of both electrochemical and electrochemiluminescence (ECL) biosensors. On one hand, CNMs bear prominent electrical conductivity, large surface area to immobilize adequate amount of biomolecules, an enhanced loading capacity, improved biocompatibility, and active site for electrochemical reaction. Additionally, CNMs could be chemically modified for the covalent coupling with the biomolecules. On the other hand, both electrochemical and ECL biosensors allow for cost-effective, rapid, and real-time detection with excellent sensitivity and selectivity, with the capability of integrating different biomolecules and CNMs on the same chip. However, currently there is not a single review, which includes CNM-based electrochemical and ECL biosensors' current progress and trends. Therefore, this review intends to survey the current progress and future trends in CNM-based electrochemical and ECL biosensors. 相似文献
57.
Steffen Stoewer Shih-Pi Ku Jozien Goense Thomas Steudel Nikos K. Logothetis John Duncan Natasha Sigala 《Magnetic resonance imaging》2010
Previous imaging work has identified a frontoparietal network in the human brain involved in many different cognitive functions, as well as in simple updates of attended information. To determine whether a similar network is present in the monkey brain and direct future electrophysiological recordings, we examined the activation of frontoparietal areas during visual stimulation in the awake, fixating monkey. We measured activity with BOLD fMRI in three animals and analyzed the data individually for each animal and at group level. We found reliable activations in lateral prefrontal and parietal areas, even though task-related decision making was minimal, as a response to simple update of visual information. These activations were significant for each individual animal, as well as at group level. Similar to human imaging results the update of visual input was enough to activate an extensive network of frontoparietal cortex in the macaque brain, a network which is normally associated with complex cognitive control processes. 相似文献
58.
Janet Tassell Natasha E. Gerstenschlager Toni Syzmanski Savannah Denning 《School science and mathematics》2020,120(6):333-344
Innovation is more imperative now than ever before given the upcoming shortage in prepared teachers and the need to produce students with a strong knowledge of mathematics. A sense of urgency is impacting teacher education/preparation programs as instructional practices need to discover how to arm teachers to increase the number of students to be not only college-ready but also desiring to pursue Science, Technology, Engineering, and Mathematics majors. As such, the purpose of this study, was to determine how the four variables (mindfulness, mathematics anxiety, self-efficacy, and mindset) are interconnected within preservice elementary teachers (PSETs), and how we as teacher educators can better address these variables within our own PSETs. Each semester included three seminars with similar overall foci including the four variables. Participants in this study were recruited from Elementary Education students at an east south central regional university enrolled in a mathematics methods course. Thirty-seven participants were divided into control (N = 20) and treatment (N = 17). In this article, we present both qualitative and quantitative results from our mixed-methods study that considered these questions. With the results of this study revealing an inter-connectedness among the four variables, this research further informs the teacher educator community. 相似文献
59.
Natasha?RozhkovskayaEmail authorView authors OrcID profile 《Algebras and Representation Theory》2018,21(5):1165-1176
We deduce from a determinant identity on quantum transfer matrices of generalized quantum integrable spin chain model their generating functions. We construct the isomorphism of Clifford algebra modules of sequences of transfer matrices and the boson space of symmetric functions. As an application, tau-functions of transfer matrices immediately arise from classical tau-functions of symmetric functions. 相似文献
60.
Hungerford NL McKinney AR Stenhouse AM McLeod MD 《Organic & biomolecular chemistry》2006,4(21):3951-3959
The temporary protection of 17alpha-alkyl-5alpha-androstane-3beta,16beta,17beta triols as boronate esters is an efficient method for their regioselective functionalisation. This has been applied to the synthesis of protein-steroid conjugates 7-10 suitable for the development of immunoassays targeting classes of steroids banned from competition in Australian horse racing and other sports. The synthesis of steroids sulfate conjugates 42 and 44 for use as reference standards is also reported. 相似文献