In this article, for the 6-man 500 m saturation diving chamber, the calculation thinking of circulating air volume, and refrigerating and heating production were introduced; the design and selection requirements of refrigeration unit, circulating fan, magnetic coupling transmission device, and heat exchanger module were also introduced; and the research findings of refrigerating and heating control technology of this system were put forward. The article can provide a reference for developing environmental control system for living chambers of deep saturation diving.

In this article, for the 6-man 500 m saturation diving chamber, the calculation thinking of circulating air volume, and refrigerating and heating production were introduced; the design and selection requirements of refrigeration unit, circulating fan, magnetic coupling transmission device, and heat exchanger module were also introduced; and the research findings of refrigerating and heating control technology of this system were put forward. The article can provide a reference for developing environmental control system for living chambers of deep saturation diving.

Objective:To investigate the effect of silver diamine fluoride(SDF)on the bonding strength between dentine and glass ion-omer cement(GIC).Methods:1 2 extracted sound molars were prepared into dintine samples and distributed into sound dentine group and demineralized dentine group.According to the treatment methods,the samples in each group were respectively divided into 3 sub-groups:A(control group),B[coated with 38% Ag(NH3 )F2 ]and C(SDF treatment with additional lighting-curing)(n =20).Then a hand-mixed conventional glass ionomer cement Fuji IX was placed on the dentine surface.After 24 h,micro tensile bond strength test and scanning electron microscope (SEM)analysis were conducted.Results:The bonding strength of demineralized dentine was higher than that of sound dentine(P <0.01 ).SDF with additional lighting-curing treated dentine showed a higer bonding strength value than only SDF treated dentin(P <0.01 ).Conclusion:SDF may improve the bonding between dentine and GIC.

Objectives:According to the present structural characteristics, the safety and the functional states of the old hyperbaric oxygen cabin used in our hospital for about 30 years, new techniques were rationally used in the reformation of the old cabin. And to keep the cabin in the first level in the country for its advancement, preeminence and technical contents in the safety and utility. Methods:Correctly understand the present national standards and regulations, carefully design the reformation plan after a thorough investigation, research and proof. And the reformation construction unit was chosen by public bidding after approved by the competent authorities of the local state. The local competent authorities and the specialized personnel in the hospital were invited during the reformation construction to exam and supervise on the spot. After the accomplishment of the reformation construction, the provincial and city competent authorities and the corresponding experts in this specialized field were invited to check and accept. Results:The check and acceptance report showed that the reformation construction was meticulous in the design and construction, the technological level was high, and several new advanced techniques had been used. The hyperbaric oxygen cabin after the reformation had a high safety and comfort. Some of the indexes had exceeded the present national standards, and achieved the national advanced standards for large medical hyperbaric oxygen cabins. Conclusions:Old cabins can be fully reformed into first level cabins in technical advancement and safety.