Could the New Absorption Cross Section of J/ψ Change the Aspect of Nuclear Absorption Mechanism

The enlarged new absorption cross sections of J/ψ by π and ρ were put into the hadron and string cascade model, JPCIAE, and the J/ψ suppression factors in P-A, O-U, S-U and Pb-Pb minimum bias collisions at 200A GeV/c were calculated with nuclear absorption mechanism only. The results seem to indicate that, with new enlarged cross section it is still hard to change the aspect that nuclear absorption mechanism itself could not easily account for the J/ψ anomalous suppression in Pb-Pb collisions.     

Reactions of Podophyllotoxin with DDQ

Introduction 2, 3-Dichloro-5, 6-dicyanobenzoquinone (DDQ) can react with lignans of the mono- arylidene-butyrolactone1, aryltetralin2, dibenzylbutane3 and aryltetralin-butyrolactone4,5 series. We have studied the reactions of this reagent with podophyllotoxin 1, which is a well-known natural product on account of its long history of use in folk medicine and the biological activity of its many derivatives6. In particular, derivatives of 4-demethyl epipodophyllotoxin are used in cancer chemo…     

核形变对J/ψ压低的效应

用强子和弦级联模型,JPCIAE,研究(200A GeV)U+U中心碰撞中核形变对J/ψ压低的效应.结果表明:在两形变核的长轴都沿束流方向的碰撞中,J/ψ压低因子约为两长轴都垂直于束流方向碰撞时的二分之一.     

Electrolytic properties and stability of solid solutions of ytterbium sulfide in calcium thioytterbate

Solid solutions of Yb₂S₃ based on CaYb₂S₄ (Yb₃S₄) were prepared by the ceramic and sol-gel methods. The samples were identified by XRD. The electric conductivity of complex sulfide phases with different backgrounds was studied. The length of phases based on CaYb₂S₄ was determined. The thermal stability of the samples was tested and the range of working temperatures was determined.     

Synthesis, structure, and physico-chemical properties of sulfide ceramics CaY2S4-Yb2S3

Solid solutions are synthesized in the system of CaY₂S₄-Yb₂S₃. Temperature and concentration dependences of electrolytic properties are studied, the sulfide ion-based conductivity is confirmed. It is shown that the high contribution of ion conductivity in the synthesized phases is due to formation of charged vacancies. Mechanisms of defect formation are suggested.     

Stability of Optical Responses from Lead-free Perovskite Films

Optics and Spectroscopy - Materials with perovskite-type crystal structure attract much attention due to their unique optical properties, such as high quantum yield of photoluminescence and high...     

Estimates for the singular values of stieltjes type transforms

We obtain two-sided estimates for the Schatten-von Neumann norms of a selfadjoint Stieltjes type transform in the space of square integrable functions.     

Macromolecules in a blend of poor and amphiphilic solvents

The globular state of the homopolymer macromolecule in a blend composed of a poor solvent and an amphiphilic solvent (substrate), whose molecules tend to be aligned with the solvent concentration gradient in the inhomogeneity region, was theoretically studied. The size of a homogeneous globule and the substrate concentration in its volume were calculated in terms of a bulk approximation. After the transition of the macromolecule from the coil to the globule state, its volume first decreases with a decrease in temperature and then begins to grow due to substrate molecules penetrating the globule. The substrate concentration in the globule insignificantly exceeds that outside the globule at identical second virial coefficients of interaction between monomer units and between substrate molecules. The expression for the free energy functional depending on the volume fractions of the components and on the orientation of substrate molecules was examined in the ground-state approximation. The orientation effect leads to narrowing of the surface layer and to a decrease in the surface tension of the homogeneous globule, thereby increasing its stability with respect to the transition to the unfolded-coil state.     

Study of physico-mechanical properties of epoxy coatings modified with liquid rubbers with terminal carboxyl group

The effect of co-condensation products of low molecular weight carboxylated butadiene and butadienenitrile rubbers with epoxy resin ED-20 on physico-mechanical properties of epoxy-rubber coatings and free films was studied.     

Electrochemical properties of solid electrolytes based on BaSm<Subscript>2</Subscript>S<Subscript>4</Subscript>

Solid solutions based on BaSm₂S_{4 ? x} mol % BaS (Sm₂S₃) are obtained. Oxide intermediates were homogenized using chemical and mechanical mixing methods. The solid solution region is determined. Complex conductivity is studied and conductivity activation energy is calculated for samples with different history. Electrolytic properties of phases based on barium thiosamarate are studied. Vacancy mechanism of defect formation is suggested.