More detailed data are cited in this paper to discuss plastic film in fields bringing benefits to cotton in Xinjiang increasing production, at that time to discuss increasingly serious environment pollution produced by plastic film residue and technicians in Xinjiang working for more than ten years to eliminate harms of plastic film residue.

This paper briefly introduced harms of plastic film residue to agricultural production, and importance of studying on the plastic film residue collector, and some issues that must be thought over when design the plastic film residue collector.

This subject is a sub subject of the subsidy project of the national natural fund, the project is studied on kinematics principle and structure techniques of roller of arc spring tooth for collecting plastic film residue.

It has been discovered that quantities of remnant plastic film in soil was negatively related to rate of cotton germination and quantities of harvest plants (r=－ 0.

Efffect of viscoelastisity of HPAM solution on residual oil film;

In connection with residual oil film of different forms after water flooding on the oleophilic rock and the viscoelasticity character of the polymer solution,the Upper-Convected Maxwell constructive equation of viscoelastic fluids was choosed,the model was analysized numerically by using computation fluid software-Polyflow.

Due the difficulty in the degradation of the used plastic film, great damage will be done to the farm land and our ecologic environment by the"white pollution"if the used plastic film is not retrieved in time.

Relationship between gastric remnant mucosa metastasis and helicobacter pylori infection in senile patients;

Purpose: To evaluate the clinical effects and surgical techniques of Neodymium-yttrium, aluminum, garnet(Nd: YAG) laser therapy for persistent pupillary membranes.