最新刊期
      卷 15 ， 期 4 ， 1997
      • Liu Yunping,Zhang Manwei,Qian Yitai,Wang Changsui
        Vol. 15, Issue 4, Pages: 193-200(1997)
        摘要：Detailed progress of nanometred materials by γ-radiation method is reviewed in this paper. The sybnthetic technology,advantage and disadvantage of this method are introduced. The prospect of this method in the field of synthesis of nanometred materials is foreseen.  
        关键词：Radiation synthesis;Nanometred materials   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598651 false
        发布时间：2024-11-05
      • Zhu Younan,Tu Tiechen,Dong Jirong,Zhang Jiashan,Lin Nianyun
        Vol. 15, Issue 4, Pages: 201-204(1997)
        摘要：Radiation induced electron transfer between nucleohistone and caffeic acid and the radiation protection effect by caffeic acid have been studied. A series of binary molecular aggregates of nucleohistone and caffeic acid with weight ratios varied from 1:1 to 60:1 at pH9 were irradiated and observed at 77K using ESR spectrometer. The ESR spectra recorded at 77K indicate that ΔHpp (0.83~0.95 mT) of central peak from mixed aggregates with several moleoular ratios are close to ΔHpp(0.94mT) of caffeic acid alone and quite different from ΔHpp (2.5mT) of nucleohistone. It is suggested that caffeic acid anion radic al is the main radical product. PST (%) defined as the percentage of the spin concentration of caffeic acid arising from transfer of captured electron by nucleohistone in the total spin concentration of caffeic acid could be obtained by resolution of composite ESR spectra. It is obvious that PST increased with the increase of nucleohistone content and reaches more than 90% from weight ratios 10:1 to 60:1. The results indicates that electron transfer from nucleohistone to caffeic acid occurred within the mixed aggregtes.  
        关键词：Nucleohistone;Caffeic acid;Electron transfer;Resolution composite   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598650 false
        发布时间：2024-11-05
      • Yang Huili,Yao Zhanghai,Liu Changhai,Xu Jun
        Vol. 15, Issue 4, Pages: 205-209(1997)
        摘要：The radiation effect of PP/LDPE blend was investigated in the presence of polyfunctional monomer,triallyl isocyanurate (TAIC). Morpholopy structure and compatibility of the blend were characterized by SEM, DSC and dynamic mechanica 1 properties. The results showed that the interphase adhesion was enhanced,the phase compatibility was improved and the mechanical properties of the blend was raised.  
        关键词：Polypropylene-polyethylene blend;Polyfunctional monomer;Radiation;Compatibility;Mechanical properties   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598649 false
        发布时间：2024-11-05
      • Lin Weizhen,Tu Tiecheng,Dong Jirong,Yao Side,Zhang Jiashan,Lin Niayun
        Vol. 15, Issue 4, Pages: 210-216(1997)
        摘要：Radiation induced electron transfer between histone H3 and some hydroxycinnamic acid derivatives within binary molecular aggregates has been in vestigated by means of resolution and simulation of ESR spectra from those aggregates γ-irradiated and recorded at 77K,respectively. The excellent linear relationships,which were made on the basis of simulation of composite ESR spectra relevant to those binary aggregates with various molar ratios of the two components,between spin transfer ratios(Rsc) and molar ratios (r) of the aggregates indicate that those hydroxycinnamic acid derivatives have effective potential for repair of the radiation damaged protein by abstracting electrons on peptide carbonyl radical anions in protein. These results are in good accord with our previous studies on radiation protection of DNA and proteins via charge transfer from the damaged biomolecules to hydroxycinnamic acid derivatives. The hydrogen bond formed between peptide carbonyl in protein and phenolic hydroxyl of hydroxycinnamic acids within the aggregates has been illustrated as the major pathway for electron transfer from H3 to caffeic acid hased upon pH dependence on the linear relationship between Rsc and r of irradiated histone H3-caffeic acid aggregates.  
        关键词：Histone H3;Caffeic acid;Sinapic acid;Ele ctron transfer;Peptide carbonyl radical anion;Phenolic hydroxyl radical   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598652 false
        发布时间：2024-11-05
      • Yuan Lihua,Feng Wen,Zheng Shiyou,Huang Guanglin
        Vol. 15, Issue 4, Pages: 217-223(1997)
        摘要：Polypropylene (PP) containing cyclic phenolic antioxidant,p-tert-butylcalix [4] arene as additive was irradiated with γ-ray in air or in vacuum at ambient temperature. The mechanical properties,variation of IR spectra and decomposition temperature by thermal analysis were mearsured for the irradiated PP sheets. Compared with BHT,p-tert-butylcalix [4] arene showed radiation stabilization towards PP during and after irradiation,especially at a high dose. By means of ESR spectra and other spectra the formation of the stable calix [4] arene radical was confirmed. No decomposition species of the calixarene was observed with the dose≤1000 kGy and the dose rate of 6.5×103kGy/h indicating the higher radiatior-resistance of the calix arene structure.  
        关键词：Calixarene;Polypropylene;γ-irradiation;Mechanical properties   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598653 false
        发布时间：2024-11-05
      • Zhang Hongyu,Wang Fuyuan,Li Ming,Zhang Zhiyi,Li Meifen
        Vol. 15, Issue 4, Pages: 224-228(1997)
        摘要：Chinonin,a kind of xanthonoid compound with four phenolic hydroxyls,is extracted from Anemarrhena asphodeloides Bunge, a sort of traditional Chinese medicine. In this paper,ESR and spin trapping techniques are used to study its scavenging effects on •OH, and 1O2 in homogeneous and heterogeneous system. It is found that chinonin possesses fairly strong scavenging activity on •OH and 1O2,which is better than that of VE. Through kinetic method,quenching rate constant of chinonin on 1O2 is determined as 7.2×108mol-1L s-1.  
        关键词：Chinonin;Active oxygen;ESR;Spin trapping   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598733 false
        发布时间：2024-11-05
      • Xu Yunshu,Fu Yibei,Fumio Yoshii,Keizo Makuuchi
        Vol. 15, Issue 4, Pages: 229-232(1997)
        摘要：Various polyfunctional monomers (PFM) were respectively kneaded into polychloroprene on a laboplastomill at 80℃,and then the compounds were irradiated by electron beam generated by an accelerator to initiate the crosslinking reaction. The results showed that crosslinking density (1/Mc) of the product is linearly proportional to the absorbed dose (D) and the initial PFM content (C0),i.e., 1/Mc=(A+KC0) D, where A,K are constant,and the values of K increased almost linearly with PFM' s specific unsaturation (moles of double bonds per 100g monomer). The tensile strength of crosslinked ploychloroprene with 4G (Polyethyleneglycol 200 dimethylacrylate) or UA101H(Urethane prepolymer) was found to be the optimum.  
        关键词：Polychloroprene;Radiation crosslinking;Polyf unctional monomer;Crosslinking density;Electron beam   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598734 false
        发布时间：2024-11-05
      • Song Daojun,Xu Dengyi,Wan Zhaoliang,He Shoulin
        Vol. 15, Issue 4, Pages: 233-237(1997)
        摘要：Irradiation and damage repair inhibitor (Caf and EDTA) post-treatment had a sub-stantial effect on DNA and RNA content and DNA self-repairing synthesis. The experiment results showed the content of DNA and RNA increased with increase doses in the seedling hypocotyl of soybean and rape,Caf and EDTA post-treatment made them further higher than that of H2O-treatment. Meanwhile,the content of DNA and RNA in hypocotyl of soybean seedling was more than that of rape. Radioactive 3H-TdR incorporation experiment showed γ-ray irradiated seeds induced unschuled DNA synthesis in the primary cultivated seeds of two crops,which was inhibited by Caf,EDTA and C+E post-treatment in the order of C+E>Caf>EDTA. Experiment also revealed irradiation and repair repressor posttreatment affected normal schuled DNA synthesis,postponed the cycle of cell division.  
        关键词：Radiation damage repair inhibitor;Crop;Radiosensitivity;DNA synthesis;Caffeine;EDTA   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598746 false
        发布时间：2024-11-05
      • Chen Shali,Liu Shuzheng
        Vol. 15, Issue 4, Pages: 238-241(1997)
        摘要：It was shown that there was a marked increase in protein synthesis of thymocytes that were metabolically labelled with 3H-Leu for 4, 6, 8 and 12 hous in low dose irradiated mice showing 33.26%, 51.48%, 51.54% and 34.98% increase respectively at different time intervals of incubation when the thymic and splenic cells were sampled 4 hours after whole body irradiation (WBI) with 75 mGy X-rays. The results suggest that there is an increase in protein synthesis with its peak at 6~8 hours after radiation. Changes in protein synthesis of immune cells in mice 4 hours after radiation and incubated for 4~12 h were observed with SDS-PAGE followed by densitometrical scanning. It is revealed that 28 kD protein synthesis was increased gradually within 12 hours of incubation and 43 kD protein synthesis was increased in the thymocytes rapidly reaching a maximum 2 hours after incubation. It was also exhibited that the synthesis of 43 kD protein and 32 kD protein was increased in the splenocytes 2 hours after incubation. These findings may have implications in the mechanism of immunoenhancement and adaptive response induced by low dose radiation.  
        关键词：Low dose radiation;Immune cell;Protein   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598764 false
        发布时间：2024-11-05
      • Zhu Hanneng,Shen Mingli
        Vol. 15, Issue 4, Pages: 242-245,241(1997)
        摘要：In order to test the influence of endothelial cell radiative injury on the tumor invasion rate at differnt time after exposure to 15Gy 60Co γ-ray, we cultured vascular endothelial cell in vitro and set up B16 melanoma invasion model. Meanwhile,the secreation of PGI2, TXB2,TPA and PAI from endothlial cells after irradiation were measured by radioimmunologic and enzyme labeling techniques. The results showed that for endothelial cells exposed to radiation the invasion rate of tumor cell were considerably larger than that of control,the secreation of PGI2 was decreased significantly,the secreation of both TXB2 and TPA were increased obviously. The phase change of invasion rate corresponds with the changes of TXB2,PGI2 and TPA. The results suggested that endothelial cells play an important role in tumor invasion and metastasis, the disorder of endothelial cell anticoagulation and fibrin lysis function caused by radiation might be the main reason for endothelial cell radiative injury accelerating the B16 melanoma invasion.  
        关键词：Radiation imjury;Vascular endothelial cell;B16melanoma cell invasion   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598784 false
        发布时间：2024-11-05
      • Liu Jinsong,Li Miaozhen,Tang Juan,He Yong,Wang Erjian
        Vol. 15, Issue 4, Pages: 246-248,252(1997)
        摘要：α-alkylaminoacetophenones (α-AK) have higher absorption coefficients in the near UV region than the usual benzoin ether and acetophenone type photoinitiators. Their initiating ability can be further improved by the addition of other initiators with longer wavelength absorption than the α-AK. The experimental results show that the reactivity enhancement depends on the combination components. An important increase can be obtained by coupling a-AK with CTX,DETX or ITX,whereas the addition of MK is less effective than TX,and BP has not significant synergetic effects on the photocuring. It should be noted that these combination systems are more suitable for the curing of pigmented formulations than clear coatings compared with other usually used commercial photoinitiators.  
        关键词：α-alkylaminoacetophenones;Combination system;UV curing   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598810 false
        发布时间：2024-11-05
      • Wang Jufang,Zhou Guangming,Li Wenjian,Chen Weiqiang,Wei Zengquan,Gao Qingxiang,Yang Hanmin
        Vol. 15, Issue 4, Pages: 249-252(1997)
        摘要：Radiation effects of cultured human hepatoma cell line SMMC-7721 irradiated by heavy ion 30MeV/u 40Ar15+ and 60Co γ-ray are compared in this study. Process of the cell death after irradiation is studied by observing the alive cells and the fixed cells. The results show that both heavy ion and γ-ray can cause serious damage to the cells,and affect the cell survival fraction. Meanwhile,the killing effect on cells by heavy ion is stronger than that by γ-ray. At the 48th hour after treatment,the relative biological effectiveness of heavy ion is 1.5 based on cell survival of 50%.  
        关键词：Heavy ion;γ-ray;Human hepatoma cell line;Survival fraction;Relative biological effectiveness   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 76598818 false
        发布时间：2024-11-05
      0