ABSTRACT
A picosecond (ps) mid-infrared (MIR) optical parametric amplifier (OPA) with LiInSe2 crystal was demonstrated for the first time. The MIR OPA was pumped by a 30 ps 1064 nm Nd:YAG laser and injected by a barium boron oxide (BBO)-based widely tunable near-infrared seed. A maximum idler pulse energy of 433 µJ at 4 µm has been obtained under a pump energy of 17 mJ, and the corresponding pulse duration was estimated to be ~13 ps. To our knowledge, this is the highest single pulse energy generated by LiInSe2 crystal. Furthermore, an idler spectrum tuning from 3.6 to 4.8 µm was investigated at fixed pump energy of 15 mJ.
ABSTRACT
The purpose of this study was to explore a green strategy about the high value-added applications of biomass. Hybrids from lignocelluloses and silver have been successfully prepared using NaBH4 as reducing reagent by an environmentally-friendly sonochemistry method. The phase, microstructure, and morphology of the hybrids were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The influences of the various reaction parameters including reaction time, lignocelluloses concentration, and types of reducing reagents on the products were investigated in detail. Silver particles can be better dispersed on the lignocelluloses matrix by adjusting reaction parameters. These hybrids may be a promising antimicrobial material for their applications in the biomedical field. This environmentally-friendly synthetic strategy reported here opens a new window to the high value-added applications of lignocelluloses.
Subject(s)
Lignin/chemical synthesis , Silver/chemistry , Lignin/chemistry , Microscopy, Electron, Scanning , Powder Diffraction , ThermogravimetryABSTRACT
OBJECTIVE: To explore the occupational and reproductive health problems of migrant female workers in electron factory. METHODS: A total number of 2000 female migrant workers were randomly sampled from three electronic factories for the study. All were investigated by questionnaire and data were input to EpiData 3.0 data base, SPSS17.0 statistical software and analyzed by Chi-square test. RESULTS: 1971 complete questionnaires were received, the recovery rate reached over 98.6%. The average age of interviewees is (21.1 ± 3.9) years. Junior employee between 16 and 18 years accounted for 19.04%. The average working age was (1.1 ± 2.2) years and about 90% were single including 0.11% of them were divorced. The main occupational hazards were: sodium hydroxide, sodium carbonate, formaldehyde, hydrochloric acid, stannic anhydride, benzene analogues, n-hexane methanol, glycol isopropanol, sulphuric acid, nitric oxide, noise, ultraviolet radiation, etc. Workplace monitoring indicated that benzene and noise levels and ultraviolet radiation were over the national OEL at fewer worksites. More than 50% female workers worked over 8 hours per day and 83% of them worked 22 days per month. The ergonomic problems: 63.86% of them worked with tedious repetitiveness and monotonous job task. About 42% of them need to be continuously with standing posture. As a consequence, there were 30% workers complain about LBP, 21% had experienced work injury; 15% â¼ 18% had some non-specific discomfort, such as insomnia, dysacusis, dizzy and headache. The incidence rate of reproductive system such as abnormal menstrual cycle (5.71%), dysmenorrhea (25.11%), congestion (8.91%), etc. The first four reproductive system disease were pelvic inflammation, adnexitis, cervical erosion, and vaginitis. There are significant differences between continuous and temporary standing work, and repeated and unrepeated job action in terms of dysmenorrheal and congestion related-discomfort(P < 0.05). CONCLUSION: There are many occupational hazards in electronic industry. And there is somewhat a serious occupational and reproductive health problems among female migrant workers, that seem to be a matter of great concern.
