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1.
Patricia D. Morrell Camille Wainwright Lawrence Flick 《School science and mathematics》2004,104(5):199-213
The purposes of this study were to observe the teaching practices occurring in student teachers' science and mathematics K‐12 classrooms, compare the student teachers' perceptions of their teaching with what was actually occurring in their classrooms, and determine which college faculty members and courses these student teachers felt contributed to the teaching methods they used. Data on each student teacher were gathered via field notes of three classes, an observation protocol completed after each lesson, and an interview. Composites were written for each of the students. The total data set of all composites was examined to see if any patterns generalizable to the whole were evident. Differences between and among grade levels and content areas surfaced and are discussed. 相似文献
2.
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4.
Douglas R. Hurst Kristen L. French April J. Angel Angela R. Williams Mary E. Rampey Tina S. Guion Kam W. Chan Camille M. Kassis Shannon L. Studer Martinez Charles F. Beam 《Journal of heterocyclic chemistry》1998,35(6):1357-1359
Several acetoacetanilides were trilithiated in excess lithium diisopropylamide, and the resulting polylithiated intermediates were regioselectively condensed with lithiated methyl salicylates followed by acid cyclization to substituted 4-oxo-N-aryl-4H-1-benzopyran-2-acetamides (benzopyranone-2-acetamides). 相似文献
5.
Abstract —In addition to the monomer-like fluorescence, a long-wavelength emission (Λmax em = 410 nm) has been detected in the dinucleoside 5'-5' pyrophosphate (CppC) at room temperature. This emission looks very similar to that previously reported for the acidic forms of Poly C (Poly C. Poly C+ and Poly I. Poly C. Poly C+ ). Only the monomer-like emission (Λmax em = 330 nm) can be detected in neutral Poly C, acidic CppC, and the neutral or protonated forms of the dinucleoside phosphate CpC.A correlation between the room temperature fluorescence of oligo and polycytidylic acids and their photochemical behaviour is found. Irradiation of all the polymeric samples at both neutral and acid pH results in the formation of minor photoproducts. They have been characterized by their absorbance (in the range 300–400 nm) and their fluorescence spectra. The same product is obtained in all cases where the monomer-like fluorescence only is detected. Distinct products are formed in neutral CppC and in the acidic Poly C forms.
The results are discussed with respect to the conformation of the oligo and polycytidylic acids and possible relationships between the 410–420 nm emission and adduct formation. An excimer is proposed as a common, intermediate excited state in both radiative deactivation and adduct formation in neutral CppC and the acidic Poly C forms. 相似文献
The results are discussed with respect to the conformation of the oligo and polycytidylic acids and possible relationships between the 410–420 nm emission and adduct formation. An excimer is proposed as a common, intermediate excited state in both radiative deactivation and adduct formation in neutral CppC and the acidic Poly C forms. 相似文献
6.
Two synthetic approaches to the novel C10H16 hydrocarbon tricyclo[4.4.0.03,9]decane ( 1 ; 2-homotwistbrendane), one of the 19 members of the adamantaneland, and its Lewis-acid-catalyzed rearrangement are described. One route starts from tricyclo[4.3.0.03,8]nonan-2-one ( 2 ; 2-twistbrendanone). The missing tenth C-atom is introduced by ring enlargement (Tiffeneau-Demjanov method). Starting from methyl 8,9,10-trinorborn-5-ene-2-endo-carboxylate ( 8 ), ring enlargement by one C-atom, regio- and stereoselective introduction of a C1 unit to a 2-endo,6-endo-disubstituted bicyclo[3.2.1]octane, and ring closure by acyloin condensation are the key steps in the second approach. 相似文献
7.
Stevens SM Chung AY Chow MC McClung SH Strachan CN Harmon AC Denslow ND Prokai L 《Rapid communications in mass spectrometry : RCM》2005,19(15):2157-2162
A fluorescent affinity tag (FAT) was synthesized and was utilized to selectively modify phosphorylated serine and threonine residues via beta-elimination and Michael addition chemistries in a 'one-step' reaction. This labeling technique was used for covalent modification of both phosphoproteins and phosphopeptides, allowing identification of these molecular species by fluorescence imaging after solution- or gel-based separation methods. In addition to the strong fluorescence of the rhodamine tag, a commercially available antibody can be used to enrich low-abundance post-labeled phosphopeptides present in complex mixtures. Application of this methodology to phosphorylation-site mapping has been evaluated for a phosphoprotein standard, bovine beta-casein. Initial results demonstrated low femtomole detection limits after fluorescence image analysis of FAT-labeled proteins or peptides. 相似文献
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9.
H. Weisen F. Hofmann M. J. Dutch J. -M. Moret J. B. Lister A. Pochelon R. A. Pitts M. Anton R. Behn S. Bernel F. Bühlmann R. Chavan B. P. Duval D. Fasel A. Favre S. Franke A. Heym Ch. Hollenstein P. Isoz B. Joye X. Llobet B. Marletaz Ph. Marmillod Y. Martin Ch. Nieswand P. J. Paris A. Perez Z. A. Pietrzyk O. Sauter W. Van Toledo G. Tonetti M. Q. Tran F. Troyon D. J. Ward 《Czechoslovak Journal of Physics》1995,45(12):1095-1110
During the first two years of operation, the TCV tokamak has produced a large variety of plasma shapes and magnetic configurations, with 1.0B
tor1.46T,I
p800kA,k2.05, –0.71. A new shape control algorithm, based on a finite element reconstruction of the plasma current in real time, has been implemented. Vertical growth rates up to 1000s–1 have been stabilized using the external coil system. Ohmic H-modes with Troyon factors (
tor
aB/I
p) up to two and densities up to 2.25×1020m–3, corresponding to the Greenwald limit, have been obtained in diverted discharges. Limiter H-modes with line averaged electron densities up to 1.7×1020m–3 have been obtained in elongated D-shaped plasmas with 360 kAI
P600 kA.Presented at 17th Symposium Plasma Physics and Technology, Prague, June 13–16, 1995.This work was partly supported by the Fonds National Suisse de la Recherche Scientifique. 相似文献
10.
Aqueous nitrosation of primary α-carbonyl diazo compounds (ethyl diazoacetate, diazoacetone, diazoacetophenones) yields α-carbonyl nitrile oxides, R? CO? CNO; their formation is demonstrated by 1,3-dipolar addition reactions. 相似文献