摘要:

The present applications of nuclear techniques in agriculture of the GDR are reviewed. An estimation of the future application potential is given.

ISSN:0021-1915    

DOI:10.1080/10256019008624277

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Studies on the workability of precise seeders by means of labelling methods has been possible due to the solution of the following problems: labelling of seeds, radiation collimation of labelled seeds being sown, elaboration of measuring and registering systems as well as processing systems of a measuring signal. The developed method allows for precise, quick and fully objective evaluation of the studied seeders to be done under natural conditions.

ISSN:0021-1915    

DOI:10.1080/10256019008624278

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Intensification of production of aldehydes by an exothermic catalysed reaction of propylen and synthese gas (so called hydroformylation) due to higher flow rates of propylene led to unstable operation of reactor. The problem of stabilisation had to be solved, i.e. the reasons for instabilities had to be found and then the method of control of transition to the higher stabilised production had to be proposed. Information obtained by the experimental methods of stimulus-response directly on the industrial unit (record of responses of concentrations of the radiotracer and of the temperatures of the cooling media in the reactor) were used in mathematical modelling of the reactor dynamics. The knowledge accumulated by simulation of the process by proposed physico-chemical model enabled control of operation of the reactor at transition to the higher requires output.

ISSN:0021-1915    

DOI:10.1080/10256019008624279

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The principal phenomena and processes occurring in the ISP furnace as well as the radiotracer methods for the investigation of charge flow dynamics have been discussed. The65Zn radioisotope was applied for investigations of the batch movement dynamics. The tracer was obtained on the way of direct neutron activation of the zincflead sinter in the nuclear reactor. The activity distribution measurements were performed by taking-out the samples. Three series of experiments were carried out in order to examine the batch material movement and its dependence on the furnace charging manner. The influence of the process parameters on the batch movement has also been discussed. The shortest descent time of the charge material is strongly favoured by the joint system of charging the furnace (i.e. coke and sinter together).

ISSN:0021-1915    

DOI:10.1080/10256019008624280

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The conditions and the physico-chemical processes occurring in the ISP furnace cause the possibility of partial reoxidation of vapourized zinc escaping from the furnace counter-current to the batch material. In order to determine the reoxidation degree and localize the active zone the radiotracer method was applied. The method of solving the convolution integral was used. The experimental part resulted indetermination of impulse characteristics of the zinc condenser; in the next step, the curves of zinc concentration distribution at the ISP furnace outlet were found on the way of calculations. The65Zn isotope was used as the tracer for the industrial experiments. About 25–30% of total amount of zinc obtained as a result of zinc oxides reduction processes undergoes reoxidation in the surface layer of the bath in the furnace shaft. The method of tracer preparation for investigating the behaviour of zinc occurring in the form of silicates and ferrates in the shaft has been proposed.

ISSN:0021-1915    

DOI:10.1080/10256019008624281

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The production of iodine as a result of gamma radiolysis of methyliodie-methylene chloride liquid solutions was studied as a function of dose and solvent composition. The effect of varying the composition of the CH3I–CH2Cl2mixtures and the amount of energy absorbed by the mixture on initial G(I2) were investigated in aerated solutions at ambient temperature. The results have been discussed in view of mechanism based on ion-molecule reactions.

ISSN:0021-1915    

DOI:10.1080/10256019008624282

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Nuclear irradiation of pnp junctions shows a pronounced change on their output electrical characteristics. Theoretical analysis, using computer programming (TRANSRAD), shows that exposing silicon transistors to nuclear radiation (neutrons, protons, electrons and gamma-rays) causes the devices to lose most of their forward gain factor. For all the analyzed irradiation conditions both junction leakage current and breakdown voltage are shown to increase pronouncely. The damage effect is found to be function of radiation fluence and energy.

ISSN:0021-1915    

DOI:10.1080/10256019008624283

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The IR absorption spectra of both unirradiated and gamma irradiated polystyrene films were investigated. It was found that the intensities of IR absorption bands decreased exponentially with increasing radiation dose. The rate of decrease k was found to depend on the type of vibration and type of bond.

ISSN:0021-1915    

DOI:10.1080/10256019008624284

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The IR-spectra of polymethylmethacryate (PMMA) have been measured before and after irradiation in air, in the region of wave number 700–4000 cm−1. The results showed that the rate of decrease in the absorbance of the IR absorption bands correlated with the type of bond, and the type of vibration whether being stretching, bending or rocking one.

ISSN:0021-1915    

DOI:10.1080/10256019008624285

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The gamma-induced ESR in CR-39 plastic has been studied and the possibility of using it as a gamma-ray dosimeter was investigated. The induced ESR was found to vary linearly with the dose up to 700 krad. The fading of the induced ESR signal at room temperature has been also investigated. The results suggest the possible use of CR-39 plastic for gamma dosimetry in the range 0 … 700 krad.

ISSN:0021-1915    

DOI:10.1080/10256019008624287

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor