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Silk mask paper with different adsorbability was prepared by changing the beating degree of silk pulp and the basis weight of silk paper, and photocatalytic silk mask paper was prepared by loading nanometer titanium dioxide (nano-TiO2) on the silk mask paper, then degradation of formaldehyde by silk mask paper loading nano-TiO2 under daylight lamps and ultraviolet lamps were investigated, respectively. Results showed that silk mask paper could adsorb formaldehyde and had higher adsorption efficiency in the initial stage, and the adsorption/desorption equilibrium could be basically achieved in 60 minutes. The adsorption capacity of silk mask paper made from silk pulp with beating degree of 45 oSR was relatively low, and it increased with the increase of beating degree, but there was little change in adsorption when the beating degree of silk pulp exceeded 65 oSR. Under daylight lamps, 26.61 %, 31.42 % and 38.21 % of formaldehyde could be degraded in 180 minutes by silk mask paper loading 1 wt%, 3 wt% and 5 wt% nano-TiO2, respectively. However, under ultraviolet (UV) lamps, 46.23 %, 55.47 % and 66.38 % of formaldehyde could be degraded within the same time, respectively. More formaldehyde could be degraded by photocatalytic silk mask paper under UV lamps than under daylight lamps, and the more the load of nano-TiO2 on the silk mask paper, the higher the degradation rate of formaldehyde within the same time.

In order to obtain paper respirator with dust resistance performance and antibacterial property, silk photo-catalytic respirator paper was made by loading nano-TiO2 photo-catalyst on silk based respirator paper. The pore structure, surface topography and TiO2 distribution, and the filtration performance of silk respirator paper were studied by using a pore size meter (PSM), a field emission scanning electron microscope (FESEM), and a filter tester, respectively. In addition, the antibacterial property of silk respirator paper was also investigated. The results showed that the pore structure and filtration performance of silk respirator paper could be controlled by changing the degree of beating of silk pulp and the basis weight of silk paper. Silk respirator paper of 45 g/m2 made from silk pulp having beating degree of 85 oSR had high filtration efficiency and appropriate filtration resistance. Nano-TiO2 particles were mainly attached to the surface of silk paper, and the loading of nano-TiO2 photo-catalyst resulted in a slight decrease in filtration resistance and filtration efficiency of silk respirator paper. It, however, improved the antibacterial property of silk respirator paper effectively.

Ammonium polyphosphate (APP) was synthesized by heating a mixture of phosphoric acid and urea, and APP/diatomite composite flame-retardant fillers were prepared by two methods: mixing and in situ polymerization. Flame-retardant paper was made by adding the prepared composite fillers to paper. The APP and APP/diatomite composite fillers were characterized by XRD, 31PNMR, SEM, FTIR, and TG. The flame retardation of paper containing these composite fillers was determined. Results showed that the prepared APP had a minimum solubility when the molar ratio of phosphoric acid to urea was 1:1.8. Under these conditions, its degree of polymerization was 91.21. After mixing and in situ polymerization, a large amount of APP was adsorbed into the surface of the diatomite. These two APP/diatomite composite fillers had similar thermal stabilities, but the flame retardation of paper containing in situ polymerized composite filler was better than that of paper containing the composite filler obtained by mixing.

“Excellent engineers education training plan” is the major project for China’s higher engineering education reform, and the stage of enterprise learning is the key to the success of it. This paper introduces the ideas and implementing measures for training light chemcal engineering specialty excellent engineers through school-enterprise cooperative education in Zhejiang University Science & Technology. The key of school-enterprise cooperative education is to establish a workable engineering knowledge and engineering ability standard and to make a study plan which throughout four stages and five practice projects, thereby cultivating students’ engineering awareness, engineering quality and engineering practice ability. Establishment of “order” educational mode can arouse the enthusiasm of enterprises to participate in talent training, and assures the success of school-enterprise cooperative education.

With its direction to decentralization, network and intelligence, field bus control system based on CAN has been applied more and more widely to the industrial control field. Aimed at solving the problems in the controlling process of pulp concentration based on analog instruments such as low precision and stability, high power consumption and excessive maintenance cost, an intelligent transmitter with CAN bus communication function is proposed here for pulp consistency control system. It can measure temperature, pressure and differential pressure signals. Methods to design the hardware and software of the transmitter are particular introduced. The hardware comprises industrial PC, single-chip MSC1211Y5, controller SJA1000 CAN and transceiver 82C250 CAN, which can realize the detection, conversion, calculation and communication of pulp concentration parameters. A main routine and a sending/receiving subroutine flow diagram on CAN communication are given in the paper. The system has features of simple structure, good applicability, low energy consumption, high reliability and strong anti-jamming ability and other advantages.