Measurement of quasi-isentropic compressibility of helium and deuterium at pressures of 1500–2000 GPa

The quasi-isentropic compressibility of helium and deuterium plasmas at pressures of up to 1500?C2000 GPa has been measured using devices with spherical geometry and an X-ray diagnostic complex comprising three betatrons and a multichannel imaging system with electro-optic gamma detectors. A deuterium density of 4.5 g/cm³ and a helium density of 3.8 g/cm³ have been obtained at pressures of 2210 and 1580 GPa, respectively. The internal energy of a deuterium plasma at the indicated pressure is about 1 MJ/cm³, which is about 100 times greater than the specific energy of condensed chemical explosives. Analysis of the obtained data shows that the degree of helium ionization under the achieved plasma compression parameters is about 0.9.     

Tritium Fuel Cycle for Muon-Catalyzed Intense Neutron Source (MC INS)

The paper presents a schematic design of a Tritium Fuel Cycle for Muon-Catalyzed Intense Neutron Source (MC INS) capable of producing 14 MeV neutrons. Based on the assumption that the fuel mixture should be used in a liquid phase different approaches are proposed to incorporate a DT cell (synthesizer) into the MC INS facility. Estimations of the total tritium inventory in the MC INS facility are given. The calculations of the DT cell operation temperature regime using the code FLOW-3D^(R) are presented. The capability to remove the thermal energy released in the DT cell of the proposed design is shown. The MC INS design is analyzed from the viewpoint of tritium safety requirements. This revised version was published online in August 2006 with corrections to the Cover Date.     

Measurement of the Temperature Dependence of the ddμ-Molecule Formation Rate in Dense Deuterium at Temperatures 300–800 K

Muon catalyzed fusion in deuterium was studied by the MCF collaboration at JINR phasotron. The measurements were carried out with a high-pressure deuterium target at the JINR phasotron in the temperature range 300–800 K at densities ≃0.5 LHD. The first experimental results for ddμ-molecule formation rate λ _ddμ in the temperature range 400–800 K with deuterium density 0.5 LHD are presented. This revised version was published online in August 2006 with corrections to the Cover Date.     

流体力学半径对估算胶体微球聚集速率常数的影响

胶体粒子聚集速率常数实验值远低于理论值一直是被普遍关注的问题.聚集速率常数的理论推导是基于粒子的几何半径来考虑的,但决定粒子扩散速率及聚集速率的应该是粒子的流体力学半径(大于几何半径),因而它是使聚集速率常数实验值低于理论值的因素之一.影响流体力学半径的因素很多,其中,带电粒子在溶液中因表面存在双电层,会明显增大流体力学半径,造成聚集速率减慢.而双电层的厚度又随溶液中离子强度的不同而改变.本工作在聚集速率的公式中引入了修正因子,即几何半径与其流体力学半径之比,以修正由于用几何半径代替流体力学半径带来的误差.其中几何半径和流体力学半径可以分别用扫描电镜(SEM)和动态光散射(DLS)来测定.以两种粒径的聚苯乙烯带电微球为例,考察了在不同离子强度下,该误差的大小.结果发现,对于半径为30 nm的微球,用流体力学半径计算的慢聚集速率常数比理论值偏低约8%.该误差随离子强度增加而减少.对于快聚集情况,流体力学半径对聚集速率基本没有影响.     

RFNC-VNIIEF Tritium Technologies for Fundamental Science

The present paper reviews the research equipment and techniques previously and currently under development in RFNC-VNIIEF to perform studies in such fundamental areas as muon catalyzed fusion, exotic quantum systems at the stability boundary, measuring magnetic moment of neutrino, etc. This revised version was published online in August 2006 with corrections to the Cover Date.     

Calculation of equilibrium composition and establishing time in a mixture of three hydrogen isotopes

A mathematical model describing the kinetics of establishing equilibrium is developed. Equilibrium concentrations of isotopic molecules for gas mixtures used in muon catalyzed fusion research are calculated. This revised version was published online in August 2006 with corrections to the Cover Date.     

Measurement of the temperature dependence of the ddμ molecule formation rate in dense deuterium at temperatures of 85–790 K

Muon catalyzed fusion (MCF) in deuterium was studied by the MCF collaboration on the Joint Institute for Nuclear Research Phasotron. The measurements were carried out with a high-pressure deuterium target in the temperature range 85–790 K at densities of about 0.5 and 0.8 of the liquid hydrogen density. The first experimental results for the ddμ molecule formation rate λ _ddμ in the temperature range 400–790 K with a deuterium density of about 0.5 of the liquid hydrogen density are presented.     

Synthetic magnetic opals

We present studies of novel nanocomposites of BiNi impregnated into the structure of opals as well as inverse opals. Atomic force microscopy and high resolution elemental analyses show a highly ordered structure and uniform distribution of the BiNi filler in the matrix. These BiNi-based nanocomposites are found to exhibit distinct ferromagnetic-like ordering with transition temperature of about 675 K. As far as we know there exists no report in literature on any BiNi compound which is magnetic.