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Membrane fouling was still a challenge for the potential application of forward osmosis (FO) in algae dewatering. In this study, the fouling behaviors of Chlorella vulgaris and Scenedesmus obliquus were compared in the FO membrane filtration process, and the roles of their soluble-extracellular polymeric substances (sEPS) and bound-EPS (bEPS) in fouling performance were investigated. The results showed that fouling behaviors could be divided into two stages including a quickly dropped and later a stable process. The bEPS of both species presented the highest flux decline (about 40.0%) by comparison with their sEPS, cells and broth. This performance was consistent with the largest dissolved organic carbon losses in feed solutions, and the highest interfacial free energy analyzed by the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. The chemical characterizations of algal foulants further showed that the severe fouling performance was also consistent with a proper ratio of carbohydrates and proteins contents in the cake layer, as well as the higher low molecular weight (LMW) components. Compared with the bEPS, the sEPS was crucial for the membrane fouling of S. obliquus, and an evolution of the membrane fouling structure was found in both species at the later filtration stage. This work clearly revealed the fundamental mechanism of FO membrane fouling caused by real microalgal suspension, and it will improve our understanding of the evolutionary fouling performances of algal EPS.

A novel cold responsive HbICE1 gene from Hevea brasiliensis was identified, and its function as a transcriptional factor in cold stress responses was further analyzed. The inducers of CBF expression (ICEs) play a crucial role in the response of plants to cold stress. To date, information is limited about the ICE genes from rubber trees (Hevea brasiliensis Muell. Arg.), a tropical woody plant. In this study, an ICE homologuous gene, referred to as HbICE1, was isolated and characterized by a combination of molecular and physiological techniques and bioinformatics analyses. The full-length cDNA of HbICE1 was 1806-bp in length and contained a 1617 bp open reading frame (ORF) encoding a putative protein of 538 amino acids. The predicted HbICE1 harbored S-rich, bHLH and ACT-like domains that were conserved in ICE1 orthologs from Arabidopsis and other plant species. Phylogenetic analysis demonstrated that HbICE1 was closely related to MeICE1 and RcICE1 as well as PeICE1, MdICE1 and PuICE1. It harbored transcriptional activity and nucleus localization. qRT-PCR analysis showed that HbICE1 was mainly expressed in leaves and stems under natural conditions. Its expression was significantly up-regulated in the leaves of the cold-resistant rubber tree clone ‘93-114’ in response to cold stress by comparison with the cold-sensitive rubber tree clone ‘Reken501’. Functional analysis in yeast revealed that HbICE1 conferred cold stress resistance. Collectively, these results suggest that HbICE1 acts as a transcriptional factor and indicatively mediates the cold resistance in rubber trees.

In this paper, a wideband difierential phase shifter has been analyzed and designed using Genetic Algorithm (GA). The difierential phase shifter consists of two flxed main lines of length ‚/2, and parallel open and short stubs of length ‚/8, which are shunted at the edge points of the main lines, respectively. With the application of GA, an impedance match and minimum phase deviation for the desired phase shift over a wide frequency band are obtained. In order to verify the optimum results, simulation experiments are made and a 45 - phase shifter is fabricated and measured. The phase shifter exhibits an impedance bandwidth (jS11j < i10dB) and a consistent 45 - (§2 - ) phase difierence bandwidth around 66%.

A shear mode magnetorheological (MR) elastomer damper is designed and manufactured, in which the MR elastomer is made by mixing RTV silicone, carbonyl iron particles and silicone oil, and solidifying under magnetic field. A flexible cantilever rotor system with single disk is constructed, and the controllability, effectiveness and stability of vibration control for the imbalance response of the rotor system using the MR damper are experimentally studied. From the test, it is found that as the strength of applied magnetic field increases, the damping and stiffness of the damper are increased; the critical speeds of the rotor system supported on the MR damper is increased distinctly, and the vibration at two critical speeds are restrained; the on-off control method may be used to control the rotor vibration while passing through the two critical speeds. The study shows that the shear mode MR elastomer damper is suitable for active vibration control of flexible rotor.

An omnidirectional antenna is presented. It is composed of dipole array. This antenna operates at 2.4 GHz for WLAN. As the radiation element, the dipole has a minimized height for reducing the size of antenna. Its size is 27mm high and 75mm length. Four dipoles that encircle a metal cylinder at the radial direction form an omnidirectional element. Along the axial direction there are three omnidirectional elements with the distance of 101mm. The gain of this antenna is 7.1 dBi at 2.4 GHz and the gain variation in azimuth plane less than 0.5dB.

To investigate the cultivating effects of several mineral matters used as root-zone media for higher plant growth in space.Four kinds of artificial and natural mineral matters were used as plant root-zone media based on lots of investigation and analysis. Nutrient liquid was delivered into the media by a long capillary material, and roots of plants obtained nutrition and water from the media. The related parameters such as plant height and photosynthetic efficiency were measured and analyzed.The growing effect in a mixture of coarse and fine ceramic particles with equal quantity proportion was the best, that in fine ceramic particles was the second best, that in clinoptilolite particles was the third and that in diorite particles was the last.The mixture of coarse and fine ceramic particles with equal quantity possesses not only fine capillary action, but also good aerating ability, and therefore is capable of being utilized as an effective root-zone media for higher plants intended to be grown in space.

To select suitable light source for higher plant cultivation in the controlled ecological life support system of the future space station.The experiment was carried out in the Space Higher Plant Cultivation Ground-based Experimental Facility (SHPCGEF); four combinations of two red and blue light-emitting diode (LED) were utilized as light sources; soilless cultivation technique with porous ceramic tubes and porous ceramic particles was utilized in the growth system.The plants grown under the shelf of pure red LED showed a lying-down state in early stage, and stood erect in later period with slender and long stems; the plants under various combinations of red and blue LED grew with nearly normal state, but the plants under the combination of 90% red and 10% blue LED possessed the best comprehensive indexes.The normal growth and development of plantlets needs two light sources of red and blue LED, and the combination of 90% red and 10% blue LED is the optimum one among those tested combinations.

In this paper, rules of air breakdown are studied and emphasis is put on the analysis and deduction of sneak time and breakdown threshold field intensity. It also shows the influence of propagation energy by different parameters.