The Dipole Correction Method for Extracting Excited State Potentials and Electronic Transition Dipoles from Fluorescence Data

We have developed a new inversion scheme for the accurate extraction of excited state potentials from fluorescence line positions and line strengths which does not make use of the Franck Condon Approximation (FCA). Our “dipole correction” method also enables the extraction of the coordinate dependence of the electronic transition dipoles. The accuracy of the potential energy surfaces (PES) thus extracted is much higher than that of the FCA- derived PES. The procedure, illustrated for the Na₂ A(¹Σ⁺_u) → X(¹Σ⁺_g) P-branch emission, results in global errors of 0.1 cm⁻¹, and average errors near the PES minimum of 0.03 cm⁻¹, with A → X electronic transition dipole function accuracies better than 1×10⁻³ Debye. We also show that it is possible to use emission data from a few select states: Global errors as small as 0.08 cm⁻¹ for the Na₂ B(¹Π_u) PES, using emissions data from only the s=0–5 low-lying levels or the s=20–23 states, are demonstrated.     

2011 CAV award announcement

The 2011 CAV (Computer-Aided Verification) Award was presented on July 17, 2011 at the 23rd annual CAV conference in Snowbird, Utah to Thomas Ball and Sriram Rajamani of Microsoft Research for their contributions to software model checking, specifically the development of the SLAM/SDV software model checker, which successfully demonstrated computer-aided verification techniques on real programs.     

Temporal property verification as a program analysis task

We describe a reduction from temporal property verification to a program analysis problem. First we present a proof system that, unlike the standard formulation, is more amenable to reasoning about infinite-state systems: disjunction is treated by partitioning, rather than enumerating, the state space and temporal operators are characterized with special sets of states called frontiers. We then describe a transformation that, with the use of procedures and nondeterminism, enables off-the-shelf program analysis tools to naturally perform the reasoning necessary for proving temporal properties (e.g. backtracking, eventuality checking, tree counterexamples for branching-time properties, abstraction refinement, etc.). Using examples drawn from the PostgreSQL database server, Apache web server, and Windows OS kernel, we demonstrate the practical viability of our work.     

Analysis of variance in capillary rheometry

The effect of deformation history (hysteresis) on transient capillary rheometric data was studied compared to conventional assumptions regarding steady state data. The factors studied were: the position instrumentation, the pressure instrumentation, entrance and exit effects, polymer melt compressibility, pressure dependence of the viscosity, and polymer melt viscous heating. Statistical analysis of variance was performed to statistically determine the sources of variance to specific degrees of confidence. The polymer melt compressibility, pressure dependence, and viscous heating were found to be statistically significant contributors of the observed variation at the 95% confidence level; the capillary length and instrumentation were not found to be significant. The results indicate that the transient behavior can vary the modeling of the apparent viscosity in a significant manner such that the model fidelity and model coefficients may vary substantially. Hence, polymer melt compressibility, pressure dependence, and viscous heating should be considered during rheological model fitting to increase model fidelity and predictive accuracy in end‐use. POLYM. ENG. SCI., 56:895–904, 2016. © 2016 Society of Plastics Engineers     

Development of organosilicone–polyurethanes as stone preservation and consolidation materials

Two organosilicone-modified polyurethanes are investigated as potential materials for the conservation and consolidation of natural stones. The materials are low molecular weight oligomers at the application stage and react with the humidity of the air to give polymers, forming continuous microlayers. The two differ in the length of the organosilicone chain, resulting in pronounced differences in their physical state: one forms a brittle glassy material (T_g ≈ 70°C). and the other, a soft rubbery material (T_g ≈ −100°C). The rate of the polymerization of the prepolymers was investigated at different conditions, showing a strong dependence on the presence of a catalyst and air humidity. Both these favorable conditions exist probably in the natural stone pores, enhancing the formation of the protective hydrophobic internal microlayer. © 1996 John Wiley & Sons, Inc.     

Pattern formation in models of fixed-bed reactors

This work reviews and compares spatiotemporal patterns in three models of adiabatic fixed catalytic beds for reactions with oscillatory kinetics: homogeneous and heterogeneous models, which are studied using generic first-order kinetics, and a detailed model of CO oxidation in the monolithic reactor. These three models describe reactors with one, two or all three phases (fluid-, solid- and adsorbed-phases), respectively. Pattern selection is based on the oscillatory or bistable nature of the kinetics and on the nature of fronts. The heterogenous and detailed models may exhibit local bistability while the homogeneous model does not admit this property: a simple conversion between the parameters of the homogeneous and heterogeneous models is suggested.

The spatiotemporal patterns in the reactor can be predicted from the sequence of phase planes spanned by the reactor. Stationary or oscillatory front solutions, oscillatory states that sweep the whole surface or excitation fronts may be realized in the homogeneous and heterogeneous models. The detailed model of the converter may exhibit oscillatory motion, which may be periodic or chaotic, in which typically a hot domain enters the reactor exit and moves quickly upstream; the following extinction occurs almost simultaneously due to strong coupling by convection.     

FPGA：挑战带来新机遇

Aitera:依靠40nm与灵活性突围 谈及未来FPGA的发展趋势,Altera亚太区副总裁兼董事总经理Erhaan Shaikh认为对于面向全球市场采用了单芯片方案的新产品,在不同地区市场上推出时需要提供各种各样的型号产品.     

赛灵思：重点领域让FPGA更光明

赛灵思（Xilinx）公司总裁兼CEO Moshe Gavrielov现在依然相信，FPGA应用将有许多机会在2009年得到增长。例如，无线基础设备制造商将会在2009年继续开发下一代无线服务设备。从全球角度来看，这就意味着制造商将继续采用FPGA开发创新的3GPPLTE（长期演进技术）和WiMax基站。对于中国来说，这意味着制造商将继续采用FPGA桔术开发创新的TD—SCDMA基站。     

Densification of transparent yttrium aluminum garnet (YAG) by SPS processing

Nano-size YAG powder co-mixed with 0.25 wt.% LiF was used to fabricate transparent polycrystalline YAG specimens by means of the Spark Plasma Sintering (SPS) technique. The presence of the LiF additive in the initial nano-powder allows obtaining fully dense disc shaped (up to 4 mm thick) transparent specimens at the outcome of a 2 h treatment at 1300 °C. The presence of LiF plays a key role in the mass transport related effects during the densification of YAG to full density and also in the elimination of the residual carbon contamination, allowing reaching a level of optical transmittance close to the theoretical value.     

赛灵思节一代无线技术创新

文章介绍了赛灵思公司的LTE基站目标设计平台、无线基础架构的半导体解决方案,以及用于射频拉远和射频卡的LTE数字前端的LTE解决方案.