Objective To determine whether a workplace-based multicomponent intervention strategy could improve BP control among Chinese working population.Methods A cluster-controlled trail,with workplaces assigned to either the...Objective To determine whether a workplace-based multicomponent intervention strategy could improve BP control among Chinese working population.Methods A cluster-controlled trail,with workplaces assigned to either the intervention or control group.60 workplaces across 20 urban regions of China were selected.4,548 hypertensive employees aged 18-60 years were assigned intervention(n=3,470)or control(n=1,078),of whom 4,205(92.5%;intervention,n=3,209;control,n=996)were included in this analysis.展开更多
The periodic precipitation occurs in a gel medium due to counter diffusion of ions,It is shown that the law derived earlier for double component systemcan be modified and found to be true in a multicomponent system.
The feasibility of separation of lead anode slime with low silver by vacuum distillation was analyzed theoretically. The volatilization rates and mass fractions of elements, influenced by distillation temperature, hea...The feasibility of separation of lead anode slime with low silver by vacuum distillation was analyzed theoretically. The volatilization rates and mass fractions of elements, influenced by distillation temperature, heat preservation time and material thickness, were investigated under laboratory conditions. The experimental results indicate that almost all of lead and bismuth can be separated from silver-contained multicomponent alloy at 1 223 K for 45 min when the chamber pressure maintains at 10-25 Pa. Silver can be easily enriched in the residue and its mass fraction increases from 3.6% to 27.8% when the distillation temperature is between 1 133 K and 1 373 K. Due to the forming ofintermetallic compounds Cu2Sb, Cul0Sb3 and Ag3Sb, the antimony could not be evaporated completely during the vacuum distillation. EDS analysis indicates that the condensate has a columnar crystal structure.展开更多
Modern radar signals mostly use low probability of intercept(LPI)waveforms,which have short pulses in the time domain,multicomponent properties,frequency hopping,combined modulation waveforms and other characteristics...Modern radar signals mostly use low probability of intercept(LPI)waveforms,which have short pulses in the time domain,multicomponent properties,frequency hopping,combined modulation waveforms and other characteristics,making the detection and estimation of LPI radar signals extremely difficult,and leading to highly required significant research on perception technology in the battlefield environment.This paper proposes a visibility graphs(VG)-based multicomponent signals detection method and a modulation waveforms parameter estimation algorithm based on the time-frequency representation(TFR).On the one hand,the frequency domain VG is used to set the dynamic threshold for detecting the multicomponent LPI radar waveforms.On the other hand,the signal is projected into the time and frequency domains by the TFR method for estimating its symbol width and instantaneous frequency(IF).Simulation performance shows that,compared with the most advanced methods,the algorithm proposed in this paper has a valuable advantage.Meanwhile,the calculation cost of the algorithm is quite low,and it is achievable in the future battlefield.展开更多
A selective method has been developed for the extraction chromatography of aluminium(Ⅲ) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline ( a liquid anion exchanger)...A selective method has been developed for the extraction chromatography of aluminium(Ⅲ) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline ( a liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium(Ⅲ) was quantitatively extracted with the 0. 065 mol / L N-n-octylaniline in 0. 013 to 0. 05 mol / L sodium succinate at a flow rate of 1. 0 mL / min. The extracted metal ion has been recovered by eluting with 25. 0 mL of 0. 05 mol / L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration,the reagent concentration,the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient ( K d ( Al(Ⅲ) ) ) versus N-n-octylaniline concentration in 0. 005 and 0. 007 mol / L sodium succinate gave the slopes of 0. 5 and 0. 7 respectively and showed the probable composition of the extracted species was 1∶ 1 ( metal to amine ratio ) and the nature of extracted species was [RR' NH + 2 Al succinate 2 ] org. . The extraction of aluminium(Ⅲ) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(Ⅲ) has been separated from multicomponent mixtures,pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium(Ⅲ) ,indium(Ⅲ) ,gallium(Ⅲ) and thallium(Ⅲ) has been developed by using suitable masking agents. The method is fast,accurate and precise.展开更多
Alloys of Pd-Au-Sn and Pd-Cu-Sn systems were investigated using metallography,electron microprobe,X ray diffraction and DTA.Partial isothermal sections were plots at 800oС and 500oС.Ternary τ-phase having tetragona...Alloys of Pd-Au-Sn and Pd-Cu-Sn systems were investigated using metallography,electron microprobe,X ray diffraction and DTA.Partial isothermal sections were plots at 800oС and 500oС.Ternary τ-phase having tetragonal structure has been established in each systems.The region of existence of phases in equilibrium with the solid solution based on palladium.展开更多
文摘Objective To determine whether a workplace-based multicomponent intervention strategy could improve BP control among Chinese working population.Methods A cluster-controlled trail,with workplaces assigned to either the intervention or control group.60 workplaces across 20 urban regions of China were selected.4,548 hypertensive employees aged 18-60 years were assigned intervention(n=3,470)or control(n=1,078),of whom 4,205(92.5%;intervention,n=3,209;control,n=996)were included in this analysis.
文摘The periodic precipitation occurs in a gel medium due to counter diffusion of ions,It is shown that the law derived earlier for double component systemcan be modified and found to be true in a multicomponent system.
基金Project(2010CI009) supported by Science Foundation of Yunnan Province,ChinaProjects(U1202271) supported by the National Natural Science Foundation of China
文摘The feasibility of separation of lead anode slime with low silver by vacuum distillation was analyzed theoretically. The volatilization rates and mass fractions of elements, influenced by distillation temperature, heat preservation time and material thickness, were investigated under laboratory conditions. The experimental results indicate that almost all of lead and bismuth can be separated from silver-contained multicomponent alloy at 1 223 K for 45 min when the chamber pressure maintains at 10-25 Pa. Silver can be easily enriched in the residue and its mass fraction increases from 3.6% to 27.8% when the distillation temperature is between 1 133 K and 1 373 K. Due to the forming ofintermetallic compounds Cu2Sb, Cul0Sb3 and Ag3Sb, the antimony could not be evaporated completely during the vacuum distillation. EDS analysis indicates that the condensate has a columnar crystal structure.
基金supported by the National Defence Pre-research Foundation of China(30502010103).
文摘Modern radar signals mostly use low probability of intercept(LPI)waveforms,which have short pulses in the time domain,multicomponent properties,frequency hopping,combined modulation waveforms and other characteristics,making the detection and estimation of LPI radar signals extremely difficult,and leading to highly required significant research on perception technology in the battlefield environment.This paper proposes a visibility graphs(VG)-based multicomponent signals detection method and a modulation waveforms parameter estimation algorithm based on the time-frequency representation(TFR).On the one hand,the frequency domain VG is used to set the dynamic threshold for detecting the multicomponent LPI radar waveforms.On the other hand,the signal is projected into the time and frequency domains by the TFR method for estimating its symbol width and instantaneous frequency(IF).Simulation performance shows that,compared with the most advanced methods,the algorithm proposed in this paper has a valuable advantage.Meanwhile,the calculation cost of the algorithm is quite low,and it is achievable in the future battlefield.
基金supported by BCUD,Pune University for providing financial assistance in form of a research project
文摘A selective method has been developed for the extraction chromatography of aluminium(Ⅲ) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline ( a liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium(Ⅲ) was quantitatively extracted with the 0. 065 mol / L N-n-octylaniline in 0. 013 to 0. 05 mol / L sodium succinate at a flow rate of 1. 0 mL / min. The extracted metal ion has been recovered by eluting with 25. 0 mL of 0. 05 mol / L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration,the reagent concentration,the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient ( K d ( Al(Ⅲ) ) ) versus N-n-octylaniline concentration in 0. 005 and 0. 007 mol / L sodium succinate gave the slopes of 0. 5 and 0. 7 respectively and showed the probable composition of the extracted species was 1∶ 1 ( metal to amine ratio ) and the nature of extracted species was [RR' NH + 2 Al succinate 2 ] org. . The extraction of aluminium(Ⅲ) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(Ⅲ) has been separated from multicomponent mixtures,pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium(Ⅲ) ,indium(Ⅲ) ,gallium(Ⅲ) and thallium(Ⅲ) has been developed by using suitable masking agents. The method is fast,accurate and precise.
文摘Alloys of Pd-Au-Sn and Pd-Cu-Sn systems were investigated using metallography,electron microprobe,X ray diffraction and DTA.Partial isothermal sections were plots at 800oС and 500oС.Ternary τ-phase having tetragonal structure has been established in each systems.The region of existence of phases in equilibrium with the solid solution based on palladium.