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131.
Hima S. Joshi Ramin Jamshidi Yitzhak Tor 《Angewandte Chemie (International ed. in English)》1999,38(18):2721-2725
Multiple emission colors can be generated with the same compound from a novel family of highly emissive and visibly fluorescent 1,10-phenanthrolines 1 . The emission wavelength of any derivative is dictated by the nature of its substituent and can be further modulated by exogenous additives such as protons or metal ions. R=H, Me, OMe, NMe2. 相似文献
132.
133.
134.
Ramin Ghorbani-Vaghei Ardeshir Khazaei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1169-1173
N-Bromobis(p-toluenesulfonyl)amine (NBBTA) is a novel and efficient reagent for the conversion of oximes to their corresponding carbonyl compounds in good yields under mild conditions. 相似文献
135.
Damping properties of viscoelastic sandwich structure can be improved by changing some parameters such as thickness of the layers, distribution of partial treatments, slippage between layers at the interfaces, cutting and its distribution at the top and core layers. Since the optimization problem may result in a thick core layer, for achieving more accuracy a new higher-order Taylor's expansion of transverse and in-plane displacement fields is developed for the core layer of sandwich cylindrical shell in which the displacement fields at the core layer are compatibly described in terms of the displacement fields at the elastic faces. The presented model includes fewer parameters than the previously developed models and therefore decreases the number of degree of freedom in the finite element modeling. The transverse normal stress in the core layer is also considered. The formulations are developed to consider the slippage between layers at the interfaces. Finally, by combining the finite element method and the optimization algorithms based on the genetic algorithm and sequential quadratic programming technique, a design optimization methodology has been formulated to maximize the damping characteristics using the optimal number and location of cuts and partial treatments with optimal thicknesses of top and core layers. 相似文献
136.
A new method for extraction and analysis of ethanol and methanol in human whole blood, urine and saliva samples based on headspace solid phase microextraction (SPME) using silver sulfide (Ag(2)S) and polyvinyl chloride (PVC) coated on silver wire is described. Unlike commercial fibers, which are coated on fused silica, the proposed fiber has a metallic base to which the coating adheres very strongly. Due to metallic base, this fiber is very durable and is thermally stable up to 250 degrees C. After optimization of coating composition and microextraction conditions, the fiber was used for sampling of methanol and ethanol from human body fluids prior to capillary gas chromatographic analysis. The high recovery (>94%), low detection limits (5.6 mg/L for ethanol and 12.8 mg/L for methanol) and excellent linearity (>0.9900) of calibration graphs made the proposed method suitable for this purpose. 相似文献
137.
Ramin Naimi 《Commentarii Mathematici Helvetici》1994,69(1):155-162
In this paper we prove the conjecture of Jankins and Neumann [JN2] about rotation numbers of products of circle homeomorphisms,
which together with other results of [EHN] and [JN2] (mentioned below) implies that a Seifert manifold admits foliations tranverse
to its fibers only if it admits such foliations with a projective transverse structure.
1991Mathematics Subject Classification: Primary 55R05, 57R30, Secondary 47A35, 57M99, 58F11.
Partially supported by a Sloan Doctoral Dissertation Fellowship, and by the Technion-Israel Institute of Technology. 相似文献
138.
Stepanyan S Hicks K Carman DS Pasyuk E Schumacher RA Smith ES Tedeschi DJ Todor L Adams G Ambrozewicz P Anciant E Anghinolfi M Asavapibhop B Audit G Avakian H Bagdasaryan H Ball JP Barrow SP Battaglieri M Beard K Bektasoglu M Bellis M Berman BL Bianchi N Biselli AS Boiarinov S Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Burkert VD Butuceanu C Calarco JR Carnahan B Chen S Ciciani L Cole PL Coleman A Cords D Corvisiero P Crabb D Crannell H Cummings JP De Sanctis E Degtyarenko PV 《Physical review letters》2003,91(25):252001
In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to an exotic baryon with strangeness S=+1 is seen in the K(+)n invariant mass spectrum. The peak is at 1.542+/-0.005 GeV/c(2) with a measured width of 0.021 GeV/c(2) FWHM, which is largely determined by experimental mass resolution. The statistical significance of the peak is (5.2+/-0.6)sigma. The mass and width of the observed peak are consistent with recent reports of a narrow S=+1 baryon by other experimental groups. 相似文献
139.
Carman DS Joo K Mestayer MD Raue BA Adams G Ambrozewicz P Anciant E Anghinolfi M Armstrong DS Asavapibhop B Audit G Auger T Avakian H Bagdasaryan H Ball JP Barrow SP Battaglieri M Beard K Bektasoglu M Bellis M Bennhold C Bianchi N Biselli AS Boiarinov S Bonner BE Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Burkert VD Butuceanu C Calarco JR Carnahan B Cazes A Cetina C Ciciani L Clark R Cole PL Coleman A Cords D Corvisiero P Crabb D Crannell H Cummings JP DeSanctis E Degtyarenko PV 《Physical review letters》2003,90(13):131804
The first measurements of the transferred polarization for the exclusive e-->p-->e(')K+Lambda--> reaction have been performed at Jefferson Laboratory using the CLAS spectrometer. A 2.567 GeV beam was used to measure the hyperon polarization over Q2 from 0.3 to 1.5 (GeV/c)(2), W from 1.6 to 2.15 GeV, and over the full K+ center-of-mass angular range. Comparison with predictions of hadrodynamic models indicates strong sensitivity to the underlying resonance contributions. A nonrelativistic quark-model interpretation of our data suggests that the ssmacr; quark pair is produced with spins predominantly antialigned. Implications for the validity of the most widely used quark-pair creation operator are discussed. 相似文献
140.
Strauch S Berman BL Adams G Ambrozewicz P Anghinolfi M Asavapibhop B Asryan G Audit G Avakian H Bagdasaryan H Baillie N Ball JP Baltzell NA Barrow S Batourine V Battaglieri M Beard K Bedlinskiy I Bektasoglu M Bellis M Benmouna N Bennhold C Biselli AS Boiarinov S Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Bültmann S Burkert VD Butuceanu C Calarco JR Careccia SL Carman DS Carnahan B Chen S Cole PL Coleman A Coltharp P Cords D Corvisiero P Crabb D Crannell H Cummings JP Degtyarenko PV 《Physical review letters》2005,95(16):162003