[en] Radiation of polysaccharides generates various types of degraded fragments by random scission. Polysaccharides can be easily degraded both in powder foam and solution. The radiation degraded polysaccharides induce various kinds of biological activities such as anti-microbial activity, promotion of plant growth, suppression of environmental stress, phytoalexins induction and can be applied not only in agriculture but also in medical fields. In this paper, the biological activities induced by radiation of chitosan, alginate, carrageenan, cellulose and pectin are reviewed for the agricultural use. (author)

[en] Poly N, N-dimethylaminoethyl methacrylate (polyDMAEMA) hydrogels prepared by γ-irradiation showed obvious temperature-sensitivity at a temperature range of 38∼40 deg. C and pH-sensitivity at pH=2.5. They also had electric response behavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electric voltage. The release rates of methylene blue (MB) from the gels at 52 deg C and pH=1.24 were faster than those at 20 deg. C and pH=10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that of no electric field. (author)

[en] The anti-oxidant properties of some non-water soluble amino acids were tested on RVNRL. Among these were cystine, tyrosine, asparagine phenyl alanine and alanine. Results indicated that all these amino acids have anti-oxidant properties with cystine, alanine and asparagine exhibiting higher anti-aging properties on RVNRL. Combination of these amino acids improved the antioxidant property on RVNRL. Keratin from chicken feathers was also tested for its antioxidant property on RVNRL. Different methods of extraction of keratin gave different aging effects on RVNRL. Reduction of keratin with Sodium Bisulfite initiated antioxidant property on RVNRL. Extraction of keratin with alkaline solution however indicated pro-oxidant properties on RVNRL. (author)

[en] At present, the world market of electron accelerator is saturated with the reliable and efficient plants of 0.3-3 MeV energy range and the power of the beam extracted into air up to 150 kW. However, such accelerators cannot satisfy the demand of new energy-intensive technologies (mainly referred to as ecological), which require accelerators with the power of an electron beam ranging from a few hundreds of kilowatts to tens of megawatts. In its turn, the megawatt power complexes require modules with a minimum unit power of hundreds of kilowatts. (author)

[en] The use of advanced composites made with carbon-, glass-, aramid-, or polyethylene fibres and epoxy- or acrylated resins is becoming increasingly prevalent within the aerospace sector. The advantages these materials offer compared to metal are making them suitable alternatives not only for secondary components but also for primary structural components on aircraft. Composites are presently cured in autoclaves using heat and pressure. Electron processing offers several advantages over thermal curing and has been investigated by Acsion personnel for over a decade. This paper discusses the latest developments at Acsion on using electron curing to manufacture components for the next generation of aerospace vehicles and to repair damaged structures on aircraft. (author)

[en] Gelatinized cassava starch was radiation graft copolymerized with acrylamide, acrylic acid or their mixture in the presence of sulphuric acid or maleic acid. Various acid concentrations were used from 0.001 to 0.1 M of sulphuric acid while the maleic acid concentrations were varied from 1 to 3% (by weight). The optimum total dose and dose rate were investigated. The saponification temperature and time had the marked effects on grafting characteristics and water absorption capacity. We found that the effect of maleic acid addition gave a profound effect on water absorption. The CHNS/O analyses indicated significant changes in the nitrogen content in the hydrolyzed starch grafted polyacrylamide with 2% maleic acid. The article explains the possible causes for the enhancement influence of mineral acid and maleic acid on grafting behavior and water absorption of the saponified cassava starch grafted polyacrylamide super absorbent polymer. (author)

[en] As the rapid progress of gamma irradiation markets, many developing countries eagerly want to own an irradiator that can adapt to a range of low-to-high-dose applications, and hope the facility is cost efficient. But few of them can afford the irradiators supplied by the developed countries. Maybe the Allance irradiator is a solution. The engineers from Beijing Institute of Nuclear Engineering (BINE) in China and from MDS Nordion in Canada, worked together for more than two years, presented a new irradiator named Allance in June. 2000. Allance is a single source-rack facility based on the design of MDS Nordion's JS series carrier irradiators, its source capacity is 1.5 million curies Co-60. The dimension of the shield is:19 meters(L)x12 meters(W)x 6 meters(H). The distance between the center of the source rack and the inner pass carriers can be about 88mm. Each irradiator comes with a total of 50 product carriers. The dimension of each carrier is 1077mm(L)x 663mm(W)x2950mm(H). The DUR (dose uniformity ratio) is less than 1.7. The source efficiency ratio can be 40% or more. The facility has three operational modes: Two Inner Pass Batch Mode, Two Outer Pass Automatic Mode and Four Pass Automatic Mode. It can satisfy various requirements of irradiation processing. The system is designed for manufacture and component sourcing in China, which partners high quality Canadian design with cost-efficient Chinese assembly. (author)

[en] A study has been carried out to investigate the effect of addition of fumed silica and hydroxy apatite into RV NR latex for the purpose of improvement of tear property of the films. Determination of water soluble protein in rubber films was also done using modified Lowry method to quantify the protein immobilization by the additives. Binding of the protein to the additives was found to enhance by addition of ZnO. Stability of the RV NR latex with fumed silica and hydroxy apatite was also evaluated. (author)

[en] The paper presents the results related to the mechanical and visco metric studies of the radiation induced effects on sodium alginate as a component of quaternary system of cellulose sulphate, poly(metilene-cogunidine) and calcium chloride used for encapsulation. The influence of absorbed dose on the mechanical resistance of capsules obtained for different sodium alginate systems demonstrate the enhanced stability of capsules from sodium alginate irradiated in the solid state under systems irradiated in aqueous solutions. The mechanical properties of the obtained capsules seem to be stable up to absorbed dose of 50 kGy. The distinct decrease of intrinsic viscosity indicates that the main change scission was the dominating process. (author)

[en] Investigations at the lab-, pilot-, and plant scale have shown that electron treatment of dissolving pulp used to produce viscose can reduce the demand for chemicals in the viscose process by as much as 40%. In this paper, the annual costs for operating four different electron accelerators for treating dissolving pulp were compared to the savings in chemical costs expected from using electron treated pulp. The major assumptions/parameters made in deriving the economic model were as follows: 1) the accelerators were operated for 6000 h/a; 2) the accelerators were located in North America at a viscose plant where pre-existing infrastructure for pulp storage and handling could be utilized; 3) only chemical savings for carbon disulphide and caustic were considered; 4) three different doses (5, 10, and 15 kGy) which span the range of possible doses that can be used for treating dissolving pulp for the viscose process were used in the analysis. Based on these assumptions, the results indicated that, at high production capacities, all four accelerators could operate at a profit, while at low production capacities, the annual operating costs for one or more of the accelerators exceeded the savings obtained from reduced chemical demand. In the case of low production capacities, the number of accelerators operating at a loss depended on whether savings in carbon disulphide alone, caustic alone, or carbon disulphide plus caustic were considered. (author)