Why did China grow so fast in the past four decades? What were the main factors? Important ones were: attitude of government; opening to the world; role of culture; exploitation of technological gap; role of foreign trained students; and role of government in the creation of modern infrastructure. These factors are likely to play a much smaller role in the future while several negative factors –populism, trade wars, environmental obstacles, aging of the population, authoritarianism and others are likely to lead to significantly lower growth rates.
Authors:Qinghua Weng, Lianguo Chen, Luxin Ye, Xiaojie Lu, Zheng Yu, Congcong Wen, Yichuan Chen, and Gang Huang
concentrations of calibration standard were from 0.53 to 530 ng/mL (0.53, 2.65, 5.3, 10.6, 26.5, 53, 106, 265, and 530 ng/mL). The QC samples were prepared in the same way to three different concentrations (low-, mid-, and high-level) at 1.06, 95.4, and 424 ng
Authors:Emerson Paes Barreto, Mariana Santos Lemos, Isabelle Bulhoes Aranha, Pedro Mauricio Büchler, and Jo Dweck
For equilibrium concentrations up to 0.53 mmol L −1 the adsorbed amount decreases for VC100 and VC120 organoclays indicating that in these cases, the largest amount of organic cation exchanged, promotes a greater difficulty for diffusion and
Some results of the plutonium determination for bone ash samples collected in Japan are presented. Mean239,240Pu concentration in the adult vertebra was 0.53 pCi/kg of ash during the period 1978 through 1983. The data are roughly in coincidence with estimated plutonium concentrations in the trabecular bone from reported air plutonium concentrations using the ICRP model and metabolic data, and weight of bone in Reference Japanese Man.
Authors:J.-S. Wan, E.-J. Langrock, W. Westmeier, P. Vater, R. Brandt, J. Adam, A. Balabekian, V. Bamblevski, M. Barabanov, V. Bradnova, P. Chaloun, V. Kalinnikov, V. Krasnov, M. Krivopustov, B. Kulakov, V. Perelygin, V. Pronskikh, A. Solnyshkin, A. Sosnin, V. Stegailov, V. Tsoupko-Sitnikov, G. Modolo, R. Odoj, S. Hashemi-Nezhad, and M. Zamani-Vallasiadou
Incineration studies of plutonium were carried out at the Synchrophasotron of the Joint Institute for Nuclear Research (JINR), Dubna, using proton beams with energies of 0.53 GeV and 1.0 GeV. Solid lead targets (8 cm in diameter and 20 cm long) were surrounded with 6 cm thick paraffin as neutron moderator and then irradiated. The transmutation of 239 Pu and the associated production of fission products 91 Sr, 92 Sr, 97 Zr, 99 Mo, 103 Ru, 105 Ru, 129 Sb, 132 Te, 133 I, 135 I and 143 Ce were studied in the present work. The plutonium samples (each 449 mg) were placed on the outer surface of moderator. For 1.0 GeV proton beam, the fission rate of 239 Pu is 0.0032 atoms per proton in one gram plutonium samples, for 0.53 GeV proton, this value is 0.0022. The experimental uncertainty is about 15%. The experiments are compared to two theoretical model calculations with moderate success, using the Dubna Cascade Model (CEM) and the LAHET code. The practical incineration rate of 239 Pu is very high. For example: if one uses 10 mA, 1 GeV proton beams under the same (fictive) experimental conditions, the incineration rate of 239 Pu via fission is 3 mg out of the 449 mg sample per day. For 0.53 GeV protons the corresponding rate is 2 mg per day.
Authors:T. Kudou, H. Ohyama, E. Simoen, C. Claeys, J. Vanhellemont, K. Sigaki, Y. Takami, and A. Fujii
Results are presented of an extended study on the degradation of electrical and optical performance and the induced lattice
defects of In0.53Ga0.47As p-i-n photodiodes, subjected to a 20 MeV alpha-ray irradiation. The difference in radiation damage with 1 MeV fast neutrons
and 1 MeV electrons is discussed taking into account the energy transfer. The radiation source dependence of performance degradation
is attributed to the difference of mass and the probability of nuclear collision for the formation of lattice defects.
Authors:A. Laissaoui, S. Mulsow, M. Benmansour, J.J. La Rosa, and M. IbnMajah
An improved and rapid method is described for the determination of 90Sr in environmental samples, through the separation of the daughter 90Y at equilibrium. The procedure is based on the HDEHP solvent extraction in combination with liquid scintillation spectrometry (LSS). A low background QuantulusÔ has been optimized for low level counting of Cerenkov radiation emitted by the hard b-emitter 90Y. The counting efficiency was 60% and the background 0.53 cpm. The reliability and reproducibility of the method have been checked using IAEA reference materials. The chemical recovery for 90Y extraction ranges from 83 to 90%.
Size-fractionated aerosol samples collected with micro-orifice impactors at Camden, NJ, a heavily industrialized urban area, and at two sites near Washington, DC, were analyzed for elemental constituents determined instrumentally from short-lived neutron activation products. A least-squares peak-fitting method was used with impactor calibration data to determine log-normal distribution parameters, i.e., mass median aerodynamic diameter (MMAD) and geometric standard deviation (
g) for particles bearing S, V, Br, and I. For these elements, MMADs ranged from 0.24 to 0.65 m; 0.23 to 0.53 m; 0.22 to 0.61 m, and 0.20 to 0.48 m, respectively.
Authors:D. Kim, Y. Jeon, T. Eom, M. Suh, and C. Lee
A study on the separation of Li isotopes was carried out with a resin having monobenzo-15-crown-5 as a functional group, synthesized by substitution reaction of chloromethylated styrene-DVB copolymer with 4-aminobenzo-15-crown-5. Adsorption properties of the resin for Li+ were invesgated with batch method in various solvents and counter anions. Upon column chromatography [0.9 cm (I. D.)×25 cm (height)] using 5% (v/v) H2O in acetonitrile as an eluent, single separation factor, , 1.053 (±0.005), (6Li/7Li)resin/ (6Li/7Li) solution was obtained by the GLUECKAUF method from the elution curve and isotope ratios.
Radioactivity of 90Sr and 137Cs in several species of herbs collected at Fajsawice and Góra Puawska located in Lublin (Poland) region was examined. Depending on the type of herb the radioactivity of strontium ranged from 0.004 to 1.808 Bq/kg dry weight whereas that from cesium varied from 0.053 to 9.853 Bq/kg. Calculated transfer factors of the radioisotopes in the plants studied revealed much stronger accumulation of strontium than cesium. Concentration of calcium and potassium in these plants has no influence on the concentration of measured radioisotopes.