The rooted tree embedding problem into points in the plane

In this paper we show that any rooted tree ofn vertices can be straight-line embedded into any setS ofn points in the plane in general position so that the image of the root is arbitrarily specified.     

High-speed computers as a supplement to graphical methods--V. HALTAFALL, a general program for calculating the composition of equilibrium mixtures

A computer program, HALTAFALL, is described which calculates the equilibrium concentrations of the species in mixtures of any number of components, which can form any number of complexes and solid phases, provided concentrations (or partial pressures) can be used in the equilibrium calculations. Of course, the equilibrium constants must be known and enough data be given about the gross composition. Some applications are indicated. The flexible input rules make it applicable to a variety of problems. From the input information, the program itself devises an efficient plan for solving the simultaneous equations. The program also provides an efficient means of finding out which of many possible solid phases can actually appear in a certain equilibrium mixture.     

Observation of antinormally ordered Hanbury Brown-Twiss correlations

We have measured antinormally ordered Hanbury Brown-Twiss correlations for coherent states of the electromagnetic field by using a stimulated parametric down-conversion process. Photons were detected by stimulated emission, rather than by absorption, so that the detection responded not only to actual photons but also to zero-point fluctuations via spontaneous emission. The observed correlations were distinct from normally ordered ones as they showed excess positive correlations, i.e., photon bunching effects, which arose from the thermal nature of zero-point fluctuations.     

Synthesis and characterization of tetrakis-silylated C60 isomers

A photochemical reaction of C(60) with disilane in a 2:3 ratio affords the isomer mixture of the tetrakis-adduct of C(60)((t)BuPh(2)Si)(4) as the major product. The use of a three-stage HPLC separation system isolated three of their isomers. Their structural assignments were based on FAB mass, UV-vis, NMR, and cyclic voltammetry (CV) measurements. The CV analysis showed that the terakis-adduct has lower oxidation and higher reduction potentials than the bis-adduct C(60)((t)BuPh(2)Si)(2) and the parent C(60).     

Nature‐Inspired Environmental “Phosphorylation” Boosts Photocatalytic H2 Production over Carbon Nitride Nanosheets under Visible‐Light Irradiation

Inspired by the crucial roles of phosphates in natural photosynthesis, we explored an environmental “phosphorylation” strategy for boosting photocatalytic H₂ production over g‐C₃N₄ nanosheets under visible light. As expected, a substantial improvement was observed in the rate of H₂ evolution to 947 μmol h^?1, and the apparent quantum yield was as high as 26.1 % at 420 nm. The synergy of enhanced proton reduction and improved hole oxidation is proposed to account for the markedly increased activity. Our findings may provide a promising and facile approach to highly efficient photocatalysis for solar‐energy conversion.     

Characterization of the bis-silylated endofullerene Sc3N@C80

The photochemical reaction of Sc(3)N@C(80) with 1,1,2,2-tetramesityl-1,2-disilirane affords the adduct as a bis-silylated product. The adduct was characterized by NMR spectroscopy and single-crystal X-ray structure analysis. The dynamic behavior of the disilirane moiety and the encapsulated Sc(3)N cluster were also investigated. The unique redox property of the adduct is reported by means of CV and DPV. Experimental results were confirmed by density functional calculations.     

Webster方程有限元法的超收敛性

<正>1前言由语音生成过程建立的数学模型是一个无界区域上的声压波动方程,引入人工边界可将这个无界区域分成一个内部有界区域和另一个无界区域,再将时间和空间进行变量分离,就可以得到一个如下一维简单的基于内部有界区间的微分方程边值问题     

Mesoporous zinc germanium oxynitride for CO2 photoreduction under visible light

Mesoporous zinc germanium oxynitride was synthesized by a template-free method at high temperature. Through optimizing redox potentials as well as improving crystallinity, this material showed enhanced activity in CO(2) photoreduction.     

Aerobic oxidation of alcohols in the liquid phase with nanoporous gold catalysts

Aerobic oxidation of alcohols in the liquid phase proceeded smoothly in the presence of nanoporous gold catalyst. The catalyst is reusable multiple times without leaching and loss of the catalytic activity. The reaction was applied successfully to a flow system. Adsorptions of O(2) and 1-phenylethanol into the AuNPore were confirmed by TDS analysis.