[en] Ginkgo seeds were treated with various doses of ⁶⁰Co γ-ray. When treated with 50 Gy, Ginkgo seeds could not sprout because of dealdembryos. But the endosperm was still vigorous in a relative long period when treated with 800 Gy and over 2 kGy, causing Ginkgo seeds to lose water more quickly, show higher conductivity and the endosperm softened and die. The respiration of Ginkgo seeds was restrained greatly after γ-irradiation. When Ginkgo seeds were treated with 50∼200 Gy γ irradiation and preserved in normal atmospheric temperature after air tight wrapping with plastic film, the preservation period of the seeds was 2 to 3 months with water content of 40.25% and 4 to 6 months water content of 35.96%, respectively

[en] Ginkgo seedlings with 6 leaves have high radiation tolerance. They didn't show evident injury within a month after irradiation under 100 Gy γ-ray. When treated with over 200 Gy, the leaves faded green colour and showed yellow colour gradually, and died finally. With irradiation under 100 Gy, SOD activity of the ginkgo leaves lowered and POD activity increased, while with irradiation over 200 Gy resulted in a much higher SOD and POD activity in leaves. The conductivity of the ginkgo leaves changed little after irradiation under 300 Gy. This result indicated that the radiation injury of ginkgo seedlings by "6"0Co γ-ray was majorly physiological damage. (authors)

[en] In this thesis, using the Gaussian 03 software, we adopted density functional theory (B3LYP) and second order perturbation theory (MP2) methods combining with the relevant consistent basis set cc-pVNZ (N=T, D, Q) and basis sets 6-311G, 6-311G^** , 6-311G (2df, 2pd), 6-311G (3df, 3pd) to optimize the geometry structure of the molecules HeNO, and then calculated their the spectroscopic constants and the anharmonic force filed based on the method adopted. Through the calculation we got the molecular balance geometry structure, a basis frequency, the turning constants, four-order and six-order centrifugal distortion constant etc. and we compared them with the related experimental value and theoretical values, forecasting the part of the spectroscopic constants, including harmonic frequencies, anharmonic constants, vibration-rotation interaction constants, third-order and forth-order force constants and Coriolis coupling constants. The results showed that, by MP2 method the calculation result was superior to those by B3LYP methods; under the basis set of 6-311G, 6-311G^**, 6-311G (2df, 2pd), 6-311G (3df, 3pd), the calculation results were widely superior to those under cc-PVNZ (N=T, D, Q). The calculation results showed that the MP2 theory method with the basis sets 6-311G, 6-311G^**, 6-311G (2df, 2pd), 6-311G (3df, 3pd) led to a calculation result very close to the experimental value, producing a preferable prediction effect of the experimental measuring some spectrum data. (authors)

[en] The colour reaction of thorium with chlorophosphonazo-mN has been studied. The results show that thorium and chlorophosphonazo-mN(1:6) can form a stable purple-red complex in the phosphoric-nitric-oxalic medium. The instability constant of the complex is 7.16 x 10^-35. The molar absorptivity and sandell sensitivity of this complex are 8.23 x 10^-4 1.mol^-1.cm^-1 and 2.82 x 10^-3 μg.cm^-2, respectively. The contrast is 120 nm. There is a maximum absorption wavelength of the complex at 670 nm. Higher sensitivity and good selectivity can also be obtained. With this method even if the sample contains a large excess of iron and uranium, the Beer's law is obeyed in the range of 0-50 μg thorium in 25 ml solution. The method is proposed for separating thorium from the sample with 734 porous cation exchange resin or 742 porous anion exchange resin. The quantity of thorium can be measured with chlorophosphonazo-mN spectrophotometry. The lower detectable limit for this method is 0.0001% of thorium

[en] The letter discusses a new way to measure fiber diameters, studies the theory of measuring fiber radius using this way, carries out numerical simulation based on this and provides experiment method as well.

[en] In general, the motor multi-pole rotor of the rare earth-cobalt magnet is made of several separate magnetic blocks. The technology to make this kind of rotor is rather complicated and difficult. This paper proposes a new mode rather than the tradiational one. The mean 8.6 x mean 4 x 15 mm and mean 12 x mean 6 x 11 mm toroids (cylinders) of multi-pole rotors of rare earth-cobalt magnets were manufactured and have been applied satisfactorily in two types of ministep-motors. (Author)

[en] Mutation rate is the probability that a particular kind of mutation occurs per unit of time which can be expressed as mutations per locus, per gene, per nucleotide, or per gamete in each generation or at each DNA replication. Mutation frequency is the proportion of the number of mutated cell or individual in a population. Mutation can be identified from either phenotype or genotype. Genotypic identification is a new method after phenotypic identification for estimating the mutation rate, in which microsatellites have been widely used for estimation of the mutation rate, but very few data are available in plants. This article summarizes the estimation methods of mutation rate and mutation frequency from the point of view of plant mutation genetics and breeding, especially paying attention to the research advances in estimation methods of microsatellite mutation rate in crops including durum wheat, chickpea, corn, common wheat and pea. Furthermore, the application of TILLING (Targeting Induced Local Lesions IN Genomes) technology in mutation screening is briefly summarized. (authors)

[en] A review of the author's work is given. It is about strengthening mechanism; surface tribology; resistance in wear, oxidation and corrosion; thermal atom chemistry in steel during ion implantation; silicides synthesis

[en] Objective: To investigate the effect of lncRNA LINC00958 on the apoptosis and radiosensitivity of colorectal cancer cells and its underlying mechanism. Methods: The pcDNA, pcDNA-LINC00958, si-NC, si-LINC00958, miR-NC, and miR-422a plasmids were transfected into SW480 cells and assigned into the pcDNA group, pcDNA-LINC00958 group, si-NC group, si-LINC00958 group, miR-NC group, miR-422a group, respectively. Anti-miR-NC and anti-miR-422a plasmids were co-transfected into SW480 cells with si-LINC00958, and assigned into the si-LINC00958 + anti-miR-NC group and si-LINC00958 + anti-miR-422a group. miR-NC and miR-422a were transfected into the WT-LINC00958 and MUT-LINC00958 cells, respectively. The fluorescence activity was detected. Cell transfection was performed by liposome method. The expression levels of miR-422a and LINC00958 were measured by qRT-PCR. The expression levels of proteins were detected by Western Blot. Cell apoptosis was assessed by flow cytometry. The radiosensitivity of colorectal cancer cells was evaluated by cell clone formation assay. The fluorescence activity was detected by dual luciferase reporter assay. Results: High expression of LINC00958 and low expression of miR-422a were observed in colorectal cancer cells. Inhibition of LINC00958 expression and overexpression of miR-422a could promote cell apoptosis and increase cell radiosensitivity of colorectal cancer cells. LINC00958 could target the regulation of miR-422a expression. Inhibition of miR-422a reversed the effect of inhibiting the expression of LINC00958 on increasing the radiosensitization and promoting cell apoptosis of colorectal cancer cells. Conclusions: Inhibition of LINC00958 expression increases the radiosensitivity and promotes the apoptosis of colorectal cancer cells. The mechanism may be related to the regulation of miR-422a, which will provide new targets and new ideas for the treatment of colorectal cancer. (authors)

[en] The HSS samples were implanted with 3 x 10¹⁷ cm^-2 of 60 keV C ions and (2-6) x 10¹⁷cm^-2 of 102 keV Co ions respectively, from a MEVVA ion source. The average beam flux was about 26.5 μA·cm^-2. The surface friction coefficient and hardness were measured, and wearing test was made. It was shown that the surface hardness of C, Co or C + Co implanted HSS increased from 15% to 50%, and the C + Co dual implanted surface of HSS was the hardest. The surface friction coefficient of HSS implanted with Co or C + Co ions decreased from 0.42 to 0.14. The wear resistance of the surface modified by C + Co dual implantation was better than that modified by C or Co single implantation. The surface of HSS implanted with Co ions had better lubricity, elasticity and tenacity. The C + Co dual implantation was one of the best methods to improve the surface wear resistance of HSS