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The real physical image of the affected limb, which is difficult to move in the traditional mirror training, can be realized easily by the rehabilitation robots. During this training, the affected limb is often in a passive state. However, with the gradual recovery of the movement ability, active mirror training becomes a better choice. Consequently, this paper took the self-developed shoulder joint rehabilitation robot with an adjustable structure as an experimental platform, and proposed a mirror training system completed by next four parts. First, the motion trajectory of the healthy limb was obtained by the Inertial Measurement Units (IMU). Then the variable universe fuzzy adaptive proportion differentiation (PD) control was adopted for inner loop, meanwhile, the muscle strength of the affected limb was estimated by the surface electromyography (sEMG). The compensation force for an assisted limb of outer loop was calculated. According to the experimental results, the control system can provide real-time assistance compensation according to the recovery of the affected limb, fully exert the training initiative of the affected limb, and make the affected limb achieve better rehabilitation training effect.

To investigate the potential application of nitrocellulose membrane (NCM) in water treatment, this study examined the photolysis of p -nitrophenol, with NCM as the source of reactive oxygen species. Effects of solution pH, light conditions, and water dissolved substances on p -nitrophenol photolysis were investigated, and possible mechanisms were discussed. The results demonstrated that the quantum yield for hydroxyl radicals from the NCM was 1.30×10 -4 , which is approximately 1.86 times higher than that from TiO 2 . The photolysis rate of p -nitrophenol in the presence of NCM was 0.0055 min -1 , which is much higher than that in pure water (9.52×10 -4 min -1 ). This promotion was mainly caused by photo-induced generation of ·OH on NCM surface under light, in which UVA plays an important role in photolysis. The photolysis rate of p -nitrophenol increased with the increase of light intensity and membrane area. Acidic solution (pH=2.0) was preferred for the degradation of p -nitrophenol, with a photolysis rate of 0.0165 min -1 ; the corresponding degradation of p -nitrophenol exceeded 90% in 120 min. The effects of dissolved substances on photolysis were significantly different. NO 3 - promoted photolysis by generation of ·OH, and dissolved organic matter decreased photolysis through light attenuation. The intermediate products of gas chromatography-mass spectrometry analysis mainly included phenol, hydroquinone, malonic acid, and oxalic acid, and the possible photolysis pathway was given accordingly.

The distribution characteristics of polycyclic aromatic hydrocarbons in runoff from the middle line source area of south-to-north water diversion project were studied. Five groups of artificial runoff fields were established to collect runoff based on the different types of land-use, the contents of 16 USEPA priority PAHs in the runoff were determined using GC/MS method. The results showed that the average concentrations of PAHs of the aqueous phase in the collected runoff samples of different land-use types decreased in the order:cultivated land (26.53 ng x L(-1)) > oak forest (20.91 ng x L(-1)) > orchard (17.59 ng x L(-1)), and the average concentrations of PAHs of the particle phase were cultivated land (1 073.72 ng x g(-1)) > orchard (652.29 ng x g(-1)) > oak forest (385.46 ng x g(-1)). The high carcinogenic components Bap were detected in both run off of cultivated land and orchard with a detected rate of 30%. According to National Recommended Water Quality Standards of priority toxic pollutants (2006 USEPA), it was found that Chr exceed standard 40%, with a detected rate of 100%. It was also found that the runoff volume and the total PAHs content in runoff increase with the slope, and PAHs loss and slope were closely related in same land-use types. Based on the Molecular Markers Indicative Law, it can be concluded that the dominant source of PAHs in runoff of study area was combustion of coal, and a small amount came from vehicle exhaust emissions. There is a certain degree of ecological risk about runoff PAHs pollution in the study area, which is worth further attention.

The surface water and sediments from the Mengjin wetland were collected. After seperated and concentrated by solid phase extraction and Soxhlet extraction, twenty kinds of organochlorine pesticides (OCPs) in the samples from the Mengjin wetland were analyzed by gas chromatography. In the surface water, 7 kinds of OCPs (incluing alpha-HCH, beta-HCH, gamma-HCH, delta-HCH, 4,4-DDT, heptachor and aldrin) were detected, with the detected ratio of 4.2% -62.5% and the content range of ND-12.21 ng/L. In the sediments, 4,4-DDE and 4,4-DDT were detected, with the detected ratio of 50%-75% and the content range of ND-64.58 ng/g. HCHs and DDTs in the surface water were both lower than the limited value defined by Environmental Quality Standards for Surface Water in China, while the surface sediments in the Mengjin wetland pose a bit high risk comparing with ERL and ERM value of risk evaluation. Distribution characteristics of OCPs components showed that HCHs usually had higher residue levels in surface water, while sediment was the fate of DDTs in the transfer process of materials from water to sediment. OCPs content in the surface water and sediments both decreased in the order of high water period > level water period > low water period. OCPs in the low water seasons were mainly the early residue, but OCPs in the high seasons had some new input in near term in the surface water and sediments. The results suggested that non-point source was one of the important sources of OCPs entering Mengjin wetland.

To understand concentration levels and sources of trace elements in PM2.5(particulate matter with aerodynamic diameters less than 2.5 microns) concentration and composition in the ambient air of Beijing, weekly samples were simultaneously collected for one year in Chegongzhuang and Qinghuayuan. Trace elements exhibited similar significant weekly variations. The strongest weekly shift occurred in winter, which reached as high as a factor of 1.6 for two consecutive weeks. No obvious seasonal pattern was found for trace elements except for that their average concentrations were much higher in winter. The EFs of trace elements were lowest in spring, probably due to frequent dust storms resulting in reduced contribution of anthropogenic sources and increased contribution of soil dust. The ambient concentrations of Se, Br, and Pb were about 1000-8000 times higher than those expected from the crustal soil in Beijing. Se was most enriched in PM2.5, reflecting the characteristics of fine particles from coal burning in Beijing. The annual mean concentration of Pb of 0.31 microgram.m-3 did not exceeded the WHO annual standard, but was at very high level compared to those measured in Los Angles and Brisbane. Comparison analysis of Pb with Br and Se shows that coal burning is probably another major source of Pb in PM2.5 other than vehicle emission.

Biphasic selective stimulation is an effective electrical stimulation mode for preventing nerve fibers against electrochemical damage, for muscle to contract smoothly, and decreasing muscle's fatigue. By use of computer simulation, this paper presents three biphasic stimulation modes respectively using monopolr, bipolar and tripolar electrodes, which can effectively stimulate nerve fibers in a selective way. The results are helpful to the clinical application of neuroelectrical stimulation.

Polymerase chain reaction-ethidium bromide (PCR-EB) method for detecting hepatitis B virus DNA (HBV-DNA) was established with good specificity and a detection limit of 1 pg HBV-DNA, minimum HBV infection dose in susceptible animal, chimpanzees, could be detected with it. Determination of inactivation of HBV-DNA could be inactivated with active chlorine 1,250 mg/L for 60 minutes, or 2,500 mg/L for 30 minutes, 10 pg HBV-DNA in purified Dane particles could be inactivated by active chlorine 625 mg/L for 10 minutes. Accordingly, use of PCR to evaluate the effects of chlorine disinfectant in inactivating HBV was feasible, and HBV-DNA was a more reliable index for inactivation of HBV than HBsAg.