[en] Highlights: • Flotation of powellite from fluorapatite at pH 2–7 using 50–80 mg/L sodium oleate can be achieved. • Oleate chemisorbs on powellite by interaction of carboxylate group with lattice Ca atoms. • Calcium dioleate precipitates can also adsorb on powellite surface. - Abstract: Flotation and adsorption performance of sodium oleate(NaOl)on powellite and fluorapatite were investigated in this work through micro-flotation tests, work of adhesion calculations, molecular dynamics simulation, micro-topography studies and FTIR measurements. The micro-flotation results show a similar flotation behaviors of powellite and fluorapatite under alkaline conditions, but a considerable difference in mineral recoveries in the pH range 2–7, which demonstrates the possibilities for separating powillite from fluorapatite under acidic conditions. The great difference in mineral recovery displays a good accordance with the obvious difference in the work of adhesion of powellite and fluorapatite at NaOl dosage range of 40–80 mg/L, obtained from flotation and contact angle measurements, respectively. The more negative interaction energy (ΔE) between NaOl and powellite/water interface from molecular dynamics simulation reveals a more easily adsorption of NaOl onto powellite than onto fluorapatite, which excellently matches with the results of flotation and work of adhesion. The results of micro-topography study shows that the adsorption of NaOl on powellite is mainly ascribed to the chemisorption of oleate ions with Ca"2"+ on powellite lattice or the precipitation of calcium dioleate agglomerates on powellite surface when it was in the solution without or with Ca"2"+, respectively. The FTIR measurements further confirm the chemisorption of oleate ions with Ca"2"+ active sites on powellite surface.

[en] We constructed a simple prototype model based on the geometry of the 56 MHz superconducting cavity for RHIC. We studied the formation, in this prototype, of bubbles of liquid helium and their thermal effects on the cavity. We found that due to the low viscosity of the liquid helium, and its small surface tension, no large bubbles formed. The tiny bubbles, generated from most of the area, behaved like light gas travelling in a free space and escaped from the trapping region. The bubbles that were generated in the trapping area, due to its descending geometry, are much bigger than the other bubbles, but due to the liquid flow generated by heating, they still are negligible compared to the size of the trapping region. We expected that the effects of bubbles in our 56 MHz cavity during operation might well be negligible.

[en] In this article, a pH sensing mesoporous MCM-41 material containing covalently bonded Ru(II) complex in the silicate network was prepared and named as Ru–MCM-41. The emission signal shows a tendency to decrease upon increasing pH values. The luminescent pH sensor can be explained by the protonation and deprotonation of the PIP ligand (PIP=2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline) and the fact that the mesoporousity of the MCM-41 matrix favors the –OH that diffused to the complex, resulting in quick emission quenching. It also shows a slight sensitivity towards dissolved molecular oxygen and varying temperatures, which, however, may not be too troublesome for actual applications. The sensing mechanism is also investigated. - Highlights: • An Ru complex was covalently grafted in mesoporous silicate network. • The emission signal decreased with increasing pH values. • The protonation and deprotonation of the ligand caused emission variation. • The emission was insensitive towards oxygen and temperature

[en] We characterized a BNL 1.3GHz half-cell SRF gun is tested for GaAs photocathode. The gun already was simulated several years ago via two-dimensional (2D) numerical codes (i.e., Superfish and Parmela) with and without the beam. In this paper, we discuss our investigation of its characteristics using a three dimensional (3D) full-wave code (CST STUDIO SUITE(trademark)).The input/pickup couplers are sited symmetrically on the same side of the gun at an angle of 180^o. In particular, the inner conductor of the pickup coupler is considerably shorter than that of the input coupler. We evaluated the cross-talk between the beam (trajectory) and the signal on the input coupler compared our findings with published results based on analytical models. The CST STUDIO SUITE(trademark) also was used to predict the field within the cavity; particularly, a combination of transient/eigenmode solvers was employed to accurately construct the RF field for the particles, which also includes the effects of the couplers. Finally, we explored the beam's dynamics with a particle in cell (PIC) simulation, validated the results and compare them with 2D code result.

[en] We examine the signatures at the SSC for supersymmetry for much of the (minimal) supersymmetric model parameter space. In particular, we survey the decay modes and signatures of gluinos and squarks. Gluinos (squarks) decay to two (one) jets and a chargino or neutralino (chi). This chi may be the (stable) lightest supersymmetric particle, LSP (and lead to missing energy). Or chi may have a two-body decay to another chi plus a W, Z or Higgs boson. Finally, it may have a three-body decay to the LSP plus q anti q, e nu, μnu, ee or μμ. Only for very light gluinos and squarks is the decay mode containing the LSP dominant. In fact, for gluinos and squarks over 500 GeV, the decays to W and Z bosons dominate for much of parameter space. We estimate the backgrounds for the case in which both gluinos decay to Z bosons. The decays of gluinos and squarks which go directly to the LSP lead to very large missing energy. We report the initial results of a study of the backgrounds for this process. 22 refs., 11 figs., 3 tabs

[en] K₂CsSb is an attractive photocathode for high current applications. With a quantum efficiency of >4% at 532nm and >10% at 355nm, it is the only cathode to have demonstrated an average current of 35mA in an accelerator environment We describe ongoing cathode development work. for the energy recovery linac being constructed at BNL Several cathodes have been created on both copper and stainless steel substrates, and their spatial uniformity and spectral response have been characterized. Preliminary lifetime measurements have been performed at high average current densities (>1 mA/mm²).

[en] In this paper, we extend the algebraic method proposed by Fan (Chaos, Solitons and Fractals 20 (2004) 609) and the improved extended tanh method by Yomba (Chaos, Solitons and Fractals 20 (2004) 1135) to uniformly construct a series of soliton-like solutions and double-like periodic solutions for nonlinear partial differential equations (NPDE). Some new soliton-like solutions and double-like periodic solutions of a (2 + 1)-dimensional dispersive long wave equation are obtained

[en] This paper analyzes the characteristics of U-Ra equilibrium coefficient change of granite-type uranium deposits in Duntou district of Xiazhuang orefield and discusses the factors affecting the uranium-radium equilibrium. The study results can be used as the evidence to rectify the logging data, determine the cut-off grade of orebody and the estimation of uranium resource in this district. (authors)

[en] Statin, a protein of 57,000 D, is present in the nuclei of quiescent of senescent fibroblasts, but is absent in their young replicating counterparts. Immunohistochemical survey of a variety of tissues demonstrates that the presence of statin is a marker for cells that are no longer involved in proliferation, i.e. those cells that are terminally differentiated. Statin expression was examined by immunofluorescence microscopy in serum-starved cultures whose replication had been reinitiated by raising the serum concentration from 0.5 to 10%. Prior to serum addition, more than 85% of the cells stained positively for statin. After stimulation with serum, the expression of statin disappeared rapidly within the first 12-14 h. On the other hand, and increase in the level of DNA synthesis, signifying entry into S phase, was observed initially at 18 h after serum stimulation, and reached maximal levels 6h later. Immunoprecipitation of statin derived from cells harvested at different intervals after serum stimulation revealed that the level of statin synthesis was reduced by 4 h and was hardly detectable at 8 h. These results demonstrate that (1) the synthesis of statin occurs primarily when cells are in a quiescent state, and declines rapidly when cells are induced to proliferate; (2) this decline precedes the transition from G1 to S phase

[en] Highlights: • We used the weighted least square with nonlinear regression method to fit experimental nuclear data. • The FITWR code has been successful applied for both light and heavy nuclei with many resonance points. • More improvements will be applied in the future, by including a new methods for nuclear data fitting. - Abstract: A computer program named FITWR has been developed and applied to the experimental total cross sections for MEV incident energy particles such as neutron and proton. The computer program FITWR adapted the weighted least square method with weighted mathematical models with nonlinear regression applied to high order fitting polynomial, in order to meet the growing demands of the experimental nuclear data. The computer program FITWR deals with variance and covariance data provided along with experimental data and yields those for the evaluated ones