Direct processes in the6Li(α, d)8Be reaction

The angular distributions of deuterons from the ⁶Li(α, d)⁸Be reaction corresponding to the 0⁺ ground state and the 2.9 MeV (2⁺) state in⁸Be have been measured at E_α = 17.3, 23.3 and 25.1 MeV. The excitation functions for this reaction have been measured at seven emission angles in the region from 12 up to 25 MeV. The experimental angular distributions are compared with theoretical predictions obtained using DWBA stripping calculations and the plane wave approximation (PWA) for various direct processes. It is shown that the experimental angular distributions can be described throughout the angular region using the simple mechanisms associated with the break-up of the ⁶Li target nuc clusters and heavy-particle stripping. The interference of these processes is taken into account.     

Vinyl derivatives of thiocaprolactam

A study is made of the reaction of N-vinylcaprolactam with phosphorus pentasulfide. When the reaction is run in xylene, thiocaprolactam is isolated, when Na₂CO₃ is present, or pyridine, a dimer of N-vinylcaprolactam is formed. As a result of a study of the reaction of thiocaprolactam with acetylene under various conditions, a method is devloped for synthesizing new sulfur- and nitrogen-containing monomers of N-vinylthiocaprolactam and S-vinylthiocaprolactam.     

Study of orientation characteristics of the 11B(5/2?, 4.445 MeV) nucleus in the 13C(d, αγ)11B reaction at Ed = 15.3 MeV

Double differential cross sections of the ¹³C(d, αγ)¹¹B(5/2⁻, 4.445 MeV) reaction were measured at E _d = 15.3 MeV. Angular dependences of the even components of density matrix spin tensors, magnetic sublevel populations, and components of multipole moment orientation tensors of the ¹¹B nucleus in this state were obtained. Experimental results were compared with theoretical data calculated under the assumption of different reaction mechanisms: deuteron pickup, heavy particle stripping, two-step mechanism of sequential cluster transfer, and compound nucleus formation.     

Contribution from Mechanisms of Direct Nucleon Transfer to Proton Spectra in the <Superscript>15</Superscript>N (α, <Emphasis Type="Italic">p</Emphasis>)<Superscript>18</Superscript>O Reaction

The differential cross section for the (α, p)¹⁸O reaction at an α-particle energy of 30 MeV is analyzed in the context of direct reaction mechanisms and the compound nucleus model. Spectroscopic amplitudes are calculated at the vertices of the diagrams illustrating triton and ¹⁴С cluster transfer reactions, including cases of mixed configurations of 1p–2d shells. The OP parameters of α–¹⁵N and p–¹⁸O interaction are found that provide the best agreement between the calculated and experimental data at an energy of ~30 MeV. It is shown that the main contribution to the production of protons comes from direct triton cluster transfer. The role of the heavy ¹⁴С cluster transfer mechanism and the compound nucleus mechanism is notable in the region of angles greater than 90°.     

Refinement of the crystal structures of biomimetic weddellites produced by microscopic fungus Aspergillus niger

The single-crystal structures of four biomimetic weddellites CaC₂O₄ · (2 + x)H₂O with different contents of zeolitic water (x = 0.10–0.24 formula units) produced by the microscopic fungus Aspergillus niger were refined from X-ray diffraction data (R = 0.029–0.038). The effect of zeolitic water content on the structural stability of weddellite was analyzed. The parameter a was shown to increase with increasing x due to the increase in the distance between water molecules along this direction. The water content and structural parameters of the synthesized weddellites are similar to those of weddellites from biofilms and kidney stones.     

Analyzing the p(<Superscript>6</Superscript>He,n gamma)<Superscript>6</Superscript>Li reaction

The differential cross section of the charge-exchange reaction p(⁶He, n)⁶Li(0⁺, 3.56 MeV) is calculated within the context of direct mechanisms: the stripping of a heavy ⁵He cluster, replacing a virtual neutron with a proton in the 5He cluster field, and the mechanism of consecutive transfer of a neutron and an α particle. The spatial structure of initial and final nucleus is determined from the dependence of various direct mechanisms contributions from spatial configurations.     

1,4-Dioxanes as products of the oxidation of N-vinyllactams

2, 5-Disubstituted 1,4-dioxanes have been obtained by the oxidation of N-vinyllactams, represented by N-vinylpyrrolidone, N-vinylpiperidone, and N-vinylcaprolactam, and their structure has been shown by independent synthesis: the reaction of trans-2, 5-dichloro-1,4-dioxanes with alkali-metal salts of the lactams also gave 2,5-di(N-2-oxopolymethyleneimino)-1,4-dioxanes.