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21.
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The properties of the 10-nucleon system are investigated with a multiconfiguration resonating-group method, which consists of +6Li,d+8Be,d+8Be*, and +6Li* cluster configurations, where6Li* and8Be* represent the rotational excited-states of6Li and8Be with orbital angular momentum equal to 2. The results show that, among reactions initiated from the +6Li incident channel, the inelastic-scattering process6Li(,)6Li* dominates. The -transfer reactions6Li(,d)8Be and6Li(,d)8Be* have smaller cross sections, but still contribute, on the average, to about one-third of the +6Li total reaction cross sections in the centre-of-mass energy region between 12 and 24 MeV. The calculated +6Li total reaction cross section at 27 MeV is equal to around 70% of the empirical value obtained by analyzing +6Li differential scattering cross-section data. This is a respectable amount, considering the complexity of the problem and that no adjustable parameters are involved in the calculation. Based on the findings of this and previous investigations, some general criteria which govern the importance of cluster-transfer processes in light nuclear systems have also been obtained. These criteria should be very useful in qualitatively understanding the behaviour of other systems that have hitherto not been studied with the multi-configuration resonating-group method. 相似文献
23.
F. Kokai Y. Koga Y. Kakudate M. Kawaguchi S. Fujiwara M. Kubota K. Fukuda 《Applied Physics A: Materials Science & Processing》1994,59(3):299-304
Laser-ionization Time-Of-Flight (TOF) mass-spectrometric studies have been carried out on the 532 nm and 1064 nm laser ablation products from a nitrogen-rich polymer. The polymer used had an elemental composition of C6.0N8.9H3.4 and consisted of C=N, C-N, and N-H chemical bonds. The TOF mass spectra observed were composed of various peaks (150 amu) depending on the ablation laser wavelength. The primary peaks were assigned to C+, CN+, CHnN+
2 (n=1–3) and C2H2N+
3 for 532 nm ablation, and C+, C+
3, HCN+, HCCN+, CH2NH+, HNCN+, H3NCN+, and C4H4N+
7 for 1064 nm ablation. The flight velocity distributions with peak velocities ranging from 8.6×103 cm/s to 3.8×104 cm/s were measured for these products. The distinct velocity distributions observed between small and large products indicate the presence of two origins in the fragment ejection process from the polymer for both 532 nm and 1064 nm ablation. Furthermore, we suggest an importance of the translational energy of the fragments for the product generation in the laser plume. 相似文献
24.
Transition of the radial electric field by electron cyclotron heating in the CHS heliotron/torsatron
25.
Alfaya RV Fujiwara ST Gushikem Y Kholin YV 《Journal of colloid and interface science》2004,269(1):32-36
3-n-propylpyridiniumsilsesquioxane chloride polymer, abbreviated as SiPy+Cl-, was used to coat a porous silica gel, SiO2, surface to form the chemically modified solid SiO2/SiPy+Cl-. The resulting polymer film was well adhered to the surface and presented an ion exchange capacity of 0.74 mmol g(-1). Metal halides, MClz [M=Fe(III), Cu(II), and Zn(II)], were adsorbed by the modified solid from ethanol solutions as neutral species by forming the surface anionic complexes described by the equation: mSiO2/SiPy+Cl-+ MClz <=> (SiO2/SiPy+)m[MCl(z+m)]m-, where the [MCl(z+m)]m- species adsorbed on the surface are FeCl4-, ZnCl4(2-), and CuCl4(2-). Accurate estimates of the specific sorption capacities and the heterogeneous stability constants of the immobilized metal complexes were determined with the aid of computational procedures. 相似文献
26.
27.
28.
Allyl 2-pyridyl sulfide or allyl phenyl sulfone on treatment with n-butyllithium in tetrahyrofuran followed by tri-n-butylstannylmethyl iodide () afforded directly the 1,3-diene in good yield. 相似文献
29.
Kyoichiro Shibatani Yuzuru Fujiwara Kiyoshi Fujii 《Journal of polymer science. Part A, Polymer chemistry》1970,8(7):1693-1703
High-resolution proton magnetic resonance and infrared spectra of poly(vinyl formal) were studied in comparison with those of the model formals obtained from stereoisomers of pentane-2,4-diol and heptane-2,4,6-triol in order to learn spectral changes due to differences of the steric structures of the polymer. In the NMR spectrum of transformal obtained from dl diol or dl,dl (syndiotactic) triol, all proton signals were well interpreted by assuming a rapid chair-chair inversion of the formal ring. On the other hand, no such inversion was observed spectroscopically in cis-formal obtained from the meso diol or meso,meso (isotactic) triol, and the cis-formal ring was supposed to take a diequatorial form preferentially. Consequently, dioxymethylene protons gave a single peak (equivalent) in trans-formal and an AB quartet (nonequivalent) in cis-formal. In the spectra of poly(vinyl formal), the dioxymethylene signal was an overlap of the singlet and quartet in dimethylsulfoxide solution. Observations of the spectra of various poly(vinyl formals) obtained from poly(vinyl alcohols) of different tacticities and study of temperature dependence of the signal have shown that the singlet and quartet are attributed to trans- and cis- formals, respectively, in the polymer spectrum also. In the infrared spectra of poly(vinyl formals), the 800 and 785 cm-1 bands were found to be related to cis- and trans-formal rings respectively. A linear relationship was confirmed between D785/D800 and trans/cis ratios determined from the peak intensities of the dioxymethylene proton signals. 相似文献
30.
Takaki K Itono Y Nagafuji A Naito Y Shishido T Takehira K Makioka Y Taniguchi Y Fujiwara Y 《The Journal of organic chemistry》2000,65(2):475-481
Three-component coupling of acylphosphonates and two carbonyl compounds leading to beta-hydroxyphosphonates has been achieved with low-valent samariums. Thus, acylphosphonates reacted with aldehydes in the presence of semicatalytic amounts of samarium metal or SmI(2) to give acyloxyphosphonates in good yields. The second coupling reaction of the acyloxyphosphonates with aldehydes or ketones promoted by SmI(2) afforded beta-hydroxyphosphonates instead of olefins. Moreover, these two reactions could be carried out in one pot. 相似文献