نتایج جستجو برای: couplings reaction
تعداد نتایج: 428859 فیلتر نتایج به سال:
In this paper we show that the neutrino observables, including an information about the transverse neutrino spin polarization, can be sensitive to the effects coming from the interference terms between the standard vector V, axial A couplings of L-handed neutrinos and exotic scalar S coupling of R-handed ones in the differential cross section. Our analysis is based on the electron neutrino-elec...
BCl3 -induced borylative cyclization of aryl-alkynes possessing ortho-EMe (E=S, O) groups represents a simple, metal-free method for the formation of C3-borylated benzothiophenes and benzofurans. The dichloro(heteroaryl)borane primary products can be protected to form synthetically ubiquitous pinacol boronate esters or used in situ in Suzuki-Miyaura cross couplings to generate 2,3-disubstituted...
The first spectroscopy of excited states in 52Ni (T(z)=-2) and 51Co (T(z)=-3/2) has been obtained using the highly selective two-neutron knockout reaction. Mirror energy differences between isobaric analogue states in these nuclei and their mirror partners are interpreted in terms of isospin nonconserving effects. A comparison between large-scale shell-model calculations and data provides the m...
We analyze near-threshold cross section data for the reaction pp→ppφ published by the DISTO collaboration and recent, still preliminary results presented by the ANKE Collaboration. We formulate a procedure to evaluate the OZI ratio at low energies by taking into account corrections from the kinematics and the final-state interaction. Combining the new data with the few measurements available at...
The α+2n and t+t clustering of the 6He ground state were investigated by means of the transfer reaction 6He( p, t)4He at 25 MeV/nucleon. The experiment was performed in inverse kinematics at GANIL with the SPEG spectrometer coupled to the MUST array. Experimental data for the transfer reaction were analyzed by a distorted wave Born approximation (DWBA) calculation, including the two neutrons an...
Photocontrol of a piperidine's Brønsted basicity was achieved by incorporation of a bulky azobenzene group and could be translated into pronounced reactivity differences between ON- and OFF-states in general base catalysis. This enabled successful photomodulation of the catalyst's activity in the nitroaldol reaction (Henry reaction). A modular synthetic route to the photoswitchable catalysts wa...
Combinations of ligand, reducing agent, and reaction conditions have been identified that allow alteration in the rate- and regioselectivity-determining step of nickel-catalyzed aldehyde-alkyne reductive couplings. Whereas previously developed protocols involve metallacycle-forming oxidative cyclization as the rate-determining step, this study illustrates that the combination of large ligands, ...
Reactive collisions between O(-) and H2 have been studied experimentally at temperatures ranging from 10 K to 300 K using a cryogenic radiofrequency 22-pole ion trap. The rate coefficients for associative detachment, leading to H2O + e(-), increase with decreasing temperature and reach a flat maximum of 1.8 × 10(-9) cm(3) s(-1) at temperatures between 20 K and 80 K. There, the overall reaction ...
We calculate the one-quark-loop amplitude for the low energy γγ → ππ collision in the context of the Nambu and Jona-Lasinio model with scalar and pseudoscalar four quark couplings to all orders in the external momenta. We show that the NJL predictions for the γγ → π + π − reaction are not far from the Born amplitude, which is close to the data, and is compatible with the chiral perturbation the...
Reaction of 6-arylamino-1,3-dialkyluracils with anhydrides of polyfluorocarboxylic acids in the presence of pyridine and subsequent cyclization with concentrated H2SO4 gave the corresponding 1,3-dialkyl-5-(polyfluoroalkyl)pyrimido[4,5-b]quinoline-2,4(1H,3H)-diones (5-polyfluoroalkyl-5-deazaalloxazines). The reactivity of these compounds towards nucleophilic reagents, such as sodium cyanoborohyd...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید