Cohomology vanishing theorem and finitely generated ideals in certain function algebras

What we want to give in this paper is when is an ideal in function algebras finitely generated in view of subelliptic estimates of -Neumann problem.     

An algorithm for nondifferentiable optimization

In this paper, we give an implementable algorithm for minimizing a locally Lipschitz function without constraints, and prove the global convergence under the -acute angle condition.     

Determination of total inorganic iodine in seawater by cathodic stripping square wave voltammetry

A method has been designed for the reduction of iodate to iodide in seawater and subsequent determination of total dissolved iodine as iodide by cathodic stripping square wave voltammetry. The pH of the sample is lowered to about 1-2 and iodate is reduced to iodide with sodium sulfite under this acidic condition. The pH of the sample is then raised to 8-9 before the concentration of iodide is measured.     

Directed polymers in Hartree-Fock approximation

A replica trick is used to map the problem of directed polymers into a quantum mechanics problem ofn-body bound states. This bound-state problem is then treated using a self-consistent method of Hartree-Fock. Ford=2, the exact result of the DP exponents is reproduced; and for complex DP, the ground-state energyE _n n² is found, confirming previous numerical results.     

钛合金（TC-6）二阶和三阶弹性常数

 用脉冲回波重叠法测量了钛合金（TC-6）的二阶、三阶弹性常数。实验中发现dμ/dp<0（p<0.17 GPa）,dμ/dp>0（p>0.17 GPa）。     

Improved method for analyzing estrogens in water by liquid chromatography-electrospray mass spectrometry

An improved LC-electrospray ionization MS method was established for four estrogens (17beta-estradiol (E2), estriol (E3), estrone (E1), and ethynyl estradiol (EE)) in environmental water. Almost complete separation of all estrogens was achieved on a phenyl column with methanol/water as the mobile phase. Quantification was achieved in the negative ionization mode using selected ion monitoring. The instrumental detection limits were 20-30 ng/l for the four analytes. In Milli-Q spiked water, the recoveries of the four estrogens were 72-81%, which was similar to those found for river water spiked with the corresponding deuterated estrogens. The detection limits for the four estrogens in river water were 0.1-0.2 ng/l. The method was used to detect residual estrogens in the Tonghui River, which receives water from a municipal sewage treatment plant in Beijing; E1 (1.1 ng/l) and E2 (0.2 ng/l) were detected.