The average incidence/case/year of Ha Bac nitrate and chemical factory during two years (2002-2003) was 1.38 incidence/case/year (2002) and 1.63 incidence/case/year (2003). The diseases were high incidence as follows: odonto-maxial-facial disease, ear-nose-throat disease. Workers with I health level and II health level were the highest: 70.33% (2002) and 65.05% (2003). The rate of workers with III health level were very high and tend to increase, remained the rate of workers with V health level.
Health ; Nitrates ; Chemical Industry

Bio-based fiber is environment friendly, reproducible, easily biodegradable. Therefore, rapid development of bio-based fiber industry is an obvious in progress to replace petrochemical resources, develop sustainable economy, build resource saving and environment friendly society. This article describes the current development of bio-based fiber industry, analyzes existing problems, indicates the trends and objectives of bio-based fiber materials technology innovation and recommends developing bio-based fibers industry of our country.
Biotechnology ; Chemical Industry

The objective of this study was to describe the occupational accidents and distribution of accidents in different groups. This is a cross sectional study in which the interview with structured questionnaire was used to collect information on occupational accidents and distribution of accidents among 2525 workers in different groups. Our results indicated that the occupational accident prevalence was 4% in 10 year period among workers of heavy, light and chemical industries. The occupational accident rate was highest in the heavy and chemical industry and the workers who worked longer in the industry have lower occupational accident prevalence.
Accidents, Occupational ; Metallurgy ; Chemical Industry

Poly (lactic acid) (PLA) is a polymer synthesized from lactic acid with good biocompatibility and biodegradability. At present, PLA manufactured on industrial scale is mainly synthesized from L-lactic acid. The obtained products have good transparency but poor heat resistance. Adding nucleating agents could increase the crystallinity of PLA, to improve heat resistance. We reviewed the progress of research on organic and inorganic nucleating agents that can be used for PLA synthesis.
Chemical Industry ; Lactic Acid ; Polyesters ; chemistry ; Polymers

Chemical Industry ; Humans ; Occupational Exposure ; Risk Assessment

Glucaric acid (GA) is derived from glucose and commonly used in chemical industry. It is also considered as one of the "Top value-added chemicals from biomass" as carbohydrate monomers to produce various synthetic polymers and bioenergy. The demand for GA in food manufacture is increasing. GA has also attracted public attentions due to its therapeutic uses such as regulating hormones, increasing the immune function and reducing the risks of cancers. Currently GA is produced by chemical oxidation. Research on production of GA via microbial synthesis is still at preliminary stage. We reviewed the advances of glucaric acid applications, preparation and quantification methods. The prospects on production of GA by microbial fermentation were also discussed.
Biomass ; Chemical Industry ; Fermentation ; Glucaric Acid ; chemistry ; Glucose ; Polymers

Biorefinery that utilizes renewable biomass for production of fuels, chemicals and bio-materials has become more and more important in chemical industry. Recently, steam explosion technology, acid and alkali treatment are the main biorefinery treatment technologies. Meanwhile, low temperature plasma technology has attracted extensive attention in biomass refining process due to its unique chemical activity and high energy. We systemically summarize the research progress of low temperature plasma technology for pretreatment, sugar platflow, selective modification, liquefaction and gasification in biomass refinery. Moreover, the mechanism of low temperature plasma in biorefinery and its further development were also discussed.
Biomass ; Biotechnology ; methods ; Biotransformation ; Chemical Industry ; Cold Temperature ; Plasma Gases

OBJECTIVETo investigate the exposure levels of carbon disulfide (CS(2)) for a chemical fiber industry.

METHODSThe concentration of CS(2) was monitored in representative workshops and types of work, and the datas of that over the years were collected.

RESULTSThe short-term exposure concentration of CS(2) about 80% of the type of work was less than or equal to 10 mg/m(3), which of more than 90% was less than or equal to 20 mg/m(3). The time weighted average concentration of CS(2) about 70% of the type of work was less than or equal to 5 mg/m(3), which of more than 90% was less than or equal to 10 mg/m(3). The short-term exposure concentration of CS(2) which was more than 15 mg/m(3) or the time weighted average concentration of CS(2) which was more than 30 mg/m(3) was only for little type of work.

CONCLUSIONThe concentration of CS(2) for the most type of work was lower, but there were still a number of types of work exposuring the higher concentration, which exceed the national occupational exposure limits.

Poly lactic acid (PLA) fibers a biodegradable fiber produced from PLA resin by melt spinning, solvent spinning or electrostatic spinning. Based on the excellent safety, comfortability, environmental protection and good mechanical properties, PLA can be widely applied in textile fabric, nonwoven, filler fabric and many downstream health products application, such as sanitary napkins, baby diapers, facial masks, and wipes.
Biotechnology ; Chemical Industry ; Lactic Acid ; Polyesters ; chemistry ; Polymers

The purpose of this study was to evaluate the effects of cyanate methacylate on the shear bond strengths to bovine dentin surfaces as a dentin primers. Seven experimental adhesives were made with different mass fraction of Isocyanatoetylmethacrylate (IEM), 40wt% HEMA (Wako Pure Chemical Industries Osaka, Japan), 0.6% camphoroquinone, 0.4% amine and ethanol as balance. dentin bonding agents (0, 2, 4, 6, 8, 10, 12%) were made and applied on the surface of bovine dentin specimens of 7 experimental groups. Shear bond strengths were measured using a universal testing machine (Instro 4466). To identify the ratio and modes of cohesive failures, microscopic examinationn was performed. The ultra-structure of resin tags were observed under scanning electron microscope. The results were as follows ; 1) A higher shear bond strengths (33.62 MPa) in group 8% of Cyanate methacrylate to dentin were found, but there were no statistically significancy between Groups (p > 0.05). 2) The higher ratio of cohesive failures mode in group 2, 6, an 10% could be seen than that in any other groups. 3) A shorter resin tags were observed in all experimental groups. This could be resulted that the preventing from the cyanate methacrylate penetrate into dentin owing to reacting it with dentin collagen. Therefore the resin tags were shorter in lengths. Whether the higher bonding strengths of dentin bonding agents can be affected was not been assured with statistic results. The results indicated that the relation between tensile strengths of the dentin adhesives to bovine dentin and resin tags formed into the dentin could not affected. The main reason of increasing the shear bond strength to bovine dentin in experimental groups could not be assured.
Adhesives ; Chemical Industry ; Collagen ; Dentin* ; Dentin-Bonding Agents ; Ethanol ; Tensile Strength