摘要:A radioisotope power generator containing 1110 curie of 210Po source is described including its working principle, basic structure, assembling technology and its performance. The generator, weighing about 2 kg, consists of a heat source, an energy converter, a thermal insulator, an erection ring and a shell. Its output reaches 1.4 watts and its efficiency is 4.2%. The dimension of the generator is 150mm in length and 120mm in diameter.
摘要:A discussion is given on analyzing several kinds of Mössbauer spectra, such as those in which their peaks are overlapped or those which come from continnously distributing internal magnetic fields. We also give spectra of three different samples to show that satisfactory results are obtained.
Automation Institute of Lanzhou Chemical Industry Corp.
1980, 03(5)
摘要:The principle and apparatus for measuring sulfur content in petroleum and its products by radioisotope X-ray method are described. Two different ranges (0~4 wt%and 0~2 wt% sulfur) could be used with the apparatus. Analysis accuracy—1% of full scale; time constant—60 sec. This method is characterized by quickness, accuracy and ease of operation.
摘要:In this paper an accurate method [with an uncertainty of ±0.5% (3σ) ] for determination of the disintegration rate of 67Ga by 4πx (LS) -γ coincidence is described. The half life and internal conversion transition intensity of 67Zn (daughter of 67Ga) were determinated simultaneously by extrapolating counting rate of the X channel to 100% efficiency and infinite dead time.
摘要:The absorbed dose of 14MeV fast neutron generated by T (D, n) 4He reaction was measured by the CaSO4 (Tm) and CaSO4 (Tm) -glucose dosimeter pair with CaSO4 (Tm) as thermoluminescence phosphor and with glucose as emitter of recoiled proton. The measurements made at 0.1 ~500 rad had a sensitivity of 9×10-2 [rad/rad fast neutron] using dosimeter pair mentioned above. The maximum error of this method was 15%. A preliminary investigation for effect of direction of the dosimeter pair showed that it was not serious in a given error range.
摘要:Circuits for converting 256-channel pulse-height analyser FH-427 into clock-controlled multiscaler mode used in Mössbauer experiments are described. After the modification the analyser can be used in both pulse-height analysis mode and time mode.
摘要:This paper describes the shimming readjustment of a 1.2 meter cyclotron as its central magnetic field was raised from 14.6kGs to 16.0kGs. Using a model magnet on the scale of 1:5 we selected the optimum sizes of shims. A table is listed for comparison of the measured results of the magnetic field drop between the model and the full scale magnet with similar shapes of shims. The magnetic field contributions by the different sizes of shims were evaluated.The internal and external H2+ beams obtained were 15×100µA and 5×100µA respectively. Therefore, the result of the shimming readjustment proved satisfactory.
摘要:This paper describes the preparation of the ultrathin TLD (thermoluminescent detector) element by depositing CaSO4:Tm onto a silver disc. The method described includes the chosing of 1~8µm CaSO4:Tm grains and the shaping sintering of 5~10µm CaSO4:Tm samples. Some of the dosimetry properties of the TLD element are given too. And a method of using the element to measure the dose absorbed by a matter irradiated by β-rays is proposed.Finally, some problems found in application are discussed. The conclusion is that according to the exposure of γ-rays, the TLD element can be used to measure relatively the dose absorbed by a matter irradiated by β-rays of an average energy between 0.2 and 0.9 MeV with deviation of ±10%.
摘要:The preparation of [9,11-3H]-quinestrol is reported. Estrone 3-cyclopentyl ether, was first oxidized by 2,3-dichloro-5,6-dicyano-quinone (DDQ) to get the dehydrogenated precursor at 9,11-positions. This was tritiated with 5% palladium-carbon catalyst to produce [9,11-3H]-estrone 3-cyclopentyl ether, then turned to [9,11-3H]-quinestrol by ethynylation with acetylene-butyllithium. The final product had a specific activity of 26 Ci/mM.
摘要:14C-dicyanodiamide was prepared by the reaction of hydrogen sulfide using isoprepanol as solvent and p-quinone dioxime as catalyst in antoclave on a water-bath at 95℃. The product had a yield of 60% with chemical purity of 85%, and radiochemical purity of 92.5%.
摘要:Dating ancient pottery by thermoluminescence is a new technique, but there are still some problems which have to be studied. Based on the sequential decay in natural radioactive series, an experimental method was created to determine the radon escape fom models of antique pottery and more acurate data could be acquired for the calculation of year dose rate. The results showed that the radon escape was less then 3%in the models of several typical kinds of pottery.