Considering the complicated situations such as uncertainly in strata pressure, high abnormal pressure coefficient, strata being easy to collapse, co-existence of well blowout and lost circulation etc, the article analyzes technical difficulties of drilling fluid with super high density, decides prescription of drilling fluid with density of over 2.

According to the actual problems existed in two-stage cementing operations in low pressure leaking formations of low permeability gas field,using blast furnace slag(BFS),floating beads and combining advantages of universal (drilling) fluid (UF) cementing technique,slag cement slurry with ultra-low density of 1.

From 1999 to 2002,by combining plot experiments with field demonstration and apllying the research of controling multiple points and multiple factors(sowing time and sowing density),the results show that,if hybrid-rape is early sown with the effective cultivation of ultra-low density,the net profit is 328 715 yuan/hm~2 more than it is late sown with the cultivation of ultra-high density.

A comparative study of sampling media for ultra-low density geochemical investigation was conducted in Jiayin area, a typical forest-swamp landscape area in central Heilongjiang.

Design of ultra high density and high count 2000 optical fiber cable for easy branching;

In order to quickly get an overview of the mineral potential of the entire eastern Tianshan terrain, a large wide-spaced geochemical survey project was commenced in 1999 in area of .

In response to the performance of the Global Goochomical Sampling (a subproject of the IGCP Project 259, International Geochemical Mapping), an orientation study was conducted in 1989-1990 to develop an optimum wide-spaced geoehemical sampling approach in Jiangxi Province, Southsart China.