ABSTRACT
Objective To evaluate disinfectant efficacy of air disinfector and ultraviolet lamp.Methods Domestic literatures were searched by computer,RevMan 5 .3 software provided by the Cochrane collaboration was used for quantitative analysis,efficacy of two kinds of air disinfection methods was compared. Results A total of 1 1 articles met the inclusion criteria. Because the heterogeneity of literatures,random effects model analysis was adopted, colony forming unit (CFU)before disinfection(WMD= -26.28,95% CI:[-60.31,7.75],P>0.05 )and immediately-after disinfection(WMD= 22.45,95% CI:[-34.24,79.13],P>0.05)had no obvious difference between two methods respectively,but CFU of air disinfector 2 hours after disinfection was significantly less than ultraviolet lamp group(WMD= -345.11,95% CI:[-478.28,-211.94],P<0.05).Conclusion Air disinfector has good continuous disinfection efficacy.
ABSTRACT
In this article, an acetone-enhanced negative photoionization (AENP) source based on a 10. 6 eV vacuum ultraviolet ( VUV) lamp was developed and coupled to a home-made time-of-flight mass spectrometer for rapid detection of trace explosives. In the AENP source, acetone molecules absorbed 10. 6 eV photons and were ionized by single photon ionization to emit photoelectrons. The photoelectrons reacted with O2 , CO2 , etc. in the atmosphere to produce mainly CO-3 negative reactant ions. With this ionization source, common explosives, N-nitrobiz ( 2-hyolorolroxy ethyl )-amine dinitrate ( DINA ) , Tetryl, trinitrotoluene ( TNT ) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), could be detected sensitively, and the limit of detection of 2 pg ( TNT) with a linear range of 3 orders of magnitude was achieved. The simple structure, high sensitivity characteristics make the AENP source as a promising ionization source for mass spectrometry.
ABSTRACT
OBJECTIVE To improve the accuracy of the radiant intensity detection of ultraviolet lamp and ensure its disinfection effect.METHODS At the different time after use of the ultraviolet lamp,its radiant intensity was measured by using the luminometer,and estimated.RESULTS If the ultraviolet lamp with good uality and worked one hour each day,with detected intensity ≥90 ?W/cm2,it could be used one year continuously,when ≥80 ?W/cm2,it could be used 6 months continuously,and when 80-75 ?W/cm2,it could be used 1 month continuously.The lump's detected intensity must be exceeded over 70 ?W/cm2.CONCLUSIONS The method that detecting the radiant intensity of ultraviolet lamp in scheduled time and consulting the used time of lump is viable.The method is real,simple,convenient and easy manipulated and ensures the effectiveness of disinfection by using ultraviolet lamp.