Recursive method for opacity expansion at finite temperature

Using a reaction operator approach, we derive the multiple-scattering induced gluon number distribution function to all orders in powers of opacity at finite temperature. The detailed balance effect is analyzed by taking into account both gluon emission and absorption in a thermal medium. We also calculate virtual corrections and show that the infrared divergence cancels out in the gluon distribution function at finite temperature.     

非平衡态/不可逆过程的热力学理论(Ⅱ)

<正> 7 解的唯一性 如果不考虑非平衡态和不可逆性,则等能密度理论中的基本命题与经典弹性理论中的在形式上完全相同。无论整个系统的动能是大还是小,图6中(sumform)_o上的面力T_i和在(sumform)_c和在的位移u_i将始终在空间坐标系x_i和时刻i下给出。与一般力学中相同,必须知道有关位移u_i及其时间导数的初始条件。它们的影响则可通过(38)和(39)向等能面转化,从而得到     

2002—Emergence of the Gas-to-Liquids Industry:a Review of Global GTL Developments

This paper reviews the status of the gas-to-liquids (GTL) industry-including current commercial plants, announced projects and the technologies that are likely to be implemented in these future projects. Today, only 35,000 B/D of GTL products (0.1% of market) are manufactured from commercial gas-based plants. Advances in technology have lowered the cost of plants to the point where GTL plants can be profitable at crude oil prices of ＄16/B. The advanced stage of development of several proposed GTL projects and attractive integrated economics, for both the gas field and plant, show that GTL can be a significant alternative for monetizing natural gas in the 21st century. GTL technologies includes more than Fischer-Tropsch technology and extends to other liquid fuels, especially in the oxygenate family (methanol, dimethyl ether, etc.).     

LATTICE DEFORMATION AND PHASE TRANSFORMATION FROM NANO-SCALE ANATASE TO NANO-SCALE RUTILE TiO_2 PREPARED BY A SOL-GEL TECHNIQUE

1. Introduction Titania TiO2 is a polymorphic oxide, inclusive of two common polymorphs: anatase (space group I41/amd, a0=0.37852 nm, c0=0.95139 nm) and rutile (space group P42/mnm, a0=0.45933 nm, c0=0.29592 nm) , both with octahedrally coordinated tetragonal structures. Anatase is a metastable structure and readily transforms to the stable morphic rutile upon heating (Gribb & Banfield, 1997). Because of their wide application in ceramics, catalysis, electronics, sensors and electrodes, they…     

100-Gb/s undersea transmission with high spectral efficiency using pre-filtered QPSK modulation format

We provide a review of our recent 100-Gb/s, high spectral efficiency (SE) experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability (MAP) detection algorithm can significantly improve SE. We transmitted 96×100-Gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed (PDM-RZ-QPSK) channels with 300% SE over 10608 km using 52-km spans of 150-μm 2 fiber and simple single-stage erbium-doped fiber amplifiers (EDFAs). We also achieved 400% SE over 4368 km using similar techniques.     

Measurements of D~0-~0 mixing and searches for CP violation:HFAG combination of all data

We present world average values for D~0-~0 mixing parameters x and y,CP violation parameters |q/P|and Arg(q/p),and strong phase differencesδandδ_(Kππ)These values are calculated by the Heavy Flavor Averaging Group(HFAG)by performing a global fit to relevant experimental measurements.The results for x and y differ significantly from zero and are inconsistent with no mixing at the level of 6.7a.The results for |q/P|and Arg(q/p)are consistent with no CP violation.The strong phase differenceδis less than 45°at 95%C.L.     

关于Dufing方程周期解的存在性与唯一性

采用Lyapunov-Schmidt约化结合Sturm特征值比较方法,将二阶Duffing方程转化为单个函数方程．通过研究函数的单调性,给出Duffing方程的周期解的存在性与唯一性．     

THE CORRELATION BETWEEN ~(13)C CHEMICAL SHIFTS OF DNA AND INTERSTRAND PURINE-PURINE CLASH

The correlation between ~(13)C chemical shifts of DNA and structure parameters (the mainaxis helix twist angle Ω, base--plane roll angle ρ, main chain torsion angle δ and pro-peller twist angle ω) has been discovered and proved indirectly. The carbons relating tothe structure parameters have been found and interpreted theoretically. Relative variationsin chemical shifts of these carbons obviously reflect purine-purine clash (steric hindrance)and have been compared with sum functions Σ of Calladine--Dickerson rules. It would bepossible to provide the information about conformation of DNA from ~(13)C NMR spectra andto observe the structure parameters of Ω,ρ,δ and ω of DNA in solution.     

C_(30)-C_(32) LANOSTANES——A NOVEL SERIES OF TETRACYCLIC TRITERPENOID HYDROCARBONS IDENTIFIED IN CHINESE TERTIARY LACUSTRINE SEDIMENTS

A series of novel tetracyclic triterpanes based on the lanostane skeleton, ranging in cars-bon number from C_(30) to C_(32), were identified for the first time in Eocene lacustrine depo-its of Biyang Depression, China. These compounds have been identified by GC, GC- MS, andcoinjection with authentic standard, as 8β(H), 9α(H)- lanostane (C_(30)), 24-methyl- lanostane(C_(31)) and 24- ethyl- lanostane (C_(32)). Mechanisms are proposed for the origin and geologicalfate of these compounds. To the best of our knowledge, this is the first confirmed occur-rence of lanostanes in the sedimentary record.     

Synthesis of bromoallenyl pyrrolidines via 1,4-addition to 1,3-enynes

The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral allene derivatives.Bromoallenyl pyrrolidines can be synthesized via 1,4-addition of sulfonamide nitrogen nucleophiles and halogens to conjugated enynes.This process can lead to simultaneous formation of a highly functionalized axially chiral allene and a stereogenic center under economical and e...