RADIOIMMUNOTOXICOLOGICAL EFFECT OF ENRICHED URANIUM ON CENTRAL AND PERIPHERAL IMMUNE CELLS AND THE PROTECTIVE ACTION OF IL－1 AND IL－2

ＲＡＤＩＯＩＭＭＵＮＯＴＯＸＩＣＯＬＯＧＩＣＡＬＥＦＦＥＣＴＯＦＥＮＲＩＣＨＥＤＵＲＡＮＩＵＭＯＮＣＥＮＴＲＡＬＡＮＤＰＥＲＩＰＨＥＲＡＬＩＭＭＵＮＥＣＥＬＬＳＡＮＤＴＨＥＰＲＯＴＥＣＴＩＶＥＡＣＴＩＯＮＯＦＩＬ－１ＡＮＤＩＬ－２￥ＺｈｕＳｈｏｕｐｅ...     

STRUCTURE EFFECTS OF SILICON AND CARBON BY CLUSTER MASS SPECTRA

Microclusters from different structures of silicon and carbon are studied by SIMS under UHV conditions in the mass range below M=200. The sputtered mass spectra of ions Sin+, Cn+ and Cn were obtained from the 10 keV O2+ primary beam bombardment. Comparisons of each spectrum in each group have shown the strong structure effects on the cluster patterns. A brief discussion on the results has been given.     

RADIATION EFFECT ON BIOSYNTHESES OF ASCORBIC ACID AND RIBOFLAVIN IN GERMINATING CHICKPEA

The influence of irradiation on biosyntheses of ascorbic acid and riboflavin in germinating chickpea seeds at ambient (25-35℃) conditions, was investigated. The rate of syntheses of these vitamins significantly increased with increasing germination time upto 120 h depending upon the treatment (P<0.05). Maximum amounts of ascorbic acid, 22.32 and 16.84 mg/100g, were found in the 0.10 kGy sample after 120 h of germination in tap and distilled water respectively. However, a radiation dose of 0.15 kGy resulted in the development of maximum values of riboflavin, 11.40 and 11.38 μ g/g, on germination in tap and distilled water respectively. A significant linear relation (r = 0-954 to 0.997) was observed between the biosyntheses of these vitamins and the germination time upto 120 h of irradiated and unirradiated chickpea seed (P<0.05).     

STUDY ON OCCURENCE FORM OF PLATINUM IN XINJIE Cu－Pt DEPOSIT BY NAA AND SCANNING PROTON MICROPROBE

ＳＴＵＤＹＯＮＯＣＣＵＲＥＮＣＥＦＯＲＭＯＦＰＬＡＴＩＮＵＭＩＮＸＩＮＪＩＥＣｕ－ＰｔＤＥＰＯＳＩＴＢＹＮＡＡＡＮＤＳＣＡＮＮＩＮＧＰＲＯＴＯＮＭＩＣＲＯＰＲＯＢＥＬｉＸｉａｏｌｉｎ，ＺｈｕＪｉｅｑｉｎｇ，ＧｕＹｉｎｇｍｅｉ，ｗｕＸｉａｎＫａｎｇ（Ｓ...     

DISTRIBUTION OF SOME ELEMENTS IN HUMAN HAIR AND ORGANS DETERMINED BY NAA

Twenty four male autopsies were obtained from Shanghai. The samples of liver, lung, kidney cortex, brain and scalp hair were collected from the autopsies. The elements As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, 8, Se and Zn were determined by neutron activation analysis (NAA). The present study provides the elemental levels of different tissues for normal male adults. The distribution pattern of elements was discussed. Great difference on distribution of some elements in different tissues was observed.     

STUDY ON THE DISTRIBUTION OF SELENIUM AND OTHER ELEMENTS IN CORN SAMPLES BY NAA AND BIOCHEMICAL TECHNIQUE

Biochemical technique was used to separate three kinds of proteins (albumin, globulin and gliadin) in corn samples froin high selenium areas and normal areas in Erxi autonomous region of Hubei Province, China. The contents of Se and other elements in these proteins were determined by neutron activation analysis (NAA). The results show that Se is enriched in corn proteins at high selenium area, while Cu, Al, Mn, V and Cl are also enriched in varying degrees.     

MEASUREMENT OF PROMPT NEUTRON SPECTRA OF ^238U FISSION INDUCED BY 10.17 AND 12.12 MeV NEUTRONS

Experimental method to measure the prompt neutron spectra of 238U fission induced by fast neutrons has been developed at HI-13 Tandem Van de Graaff Accelerator Laboratory of CIAE.These techniques employ a multi-segment fission chamber and two liquid scintillator neutron detectors.TOF(time of flight)techniques are used for primary neutrons to select the fission events induced by monoenergetic neutron from 2H(d,n) reactions instead of breakup neutrons from 2H(d,np) reactions.The fission neutron TOF spectra are measured in coincidence with the fission fragments to distinguish fission neutrons from other secondary neutrons.The method permits measurements to a fairly good accuracy under large neutron and gamma ray background.The techniques are described and experimental spectra are presented.     

MEASUREMENTS OF TOTAL CROSS SECTIONS FOR K－SHELL IONIZATION BY ELECTRON BOMBARDMENT

ＭＥＡＳＵＲＥＭＥＮＴＳＯＦＴＯＴＡＬＣＲＯＳＳＳＥＣＴＩＯＮＳＦＯＲＫ－ＳＨＥＬＬＩＯＮＩＺＡＴＩＯＮＢＹＥＬＥＣＴＲＯＮＢＯＭＢＡＲＤＭＥＮＴＬｉＪｉｎｇｗｅｎ（李景文）；ＤｏｎｇＺｈｉｑｉａｎｇ（董志强）；ＺｅｎｇＸｉａｎｔａｎｇ（曾宪堂），Ｈ...     

A STUDY OF ANTINODULARIZING PROPERTIES OF Pb, Bi, Al AND Ti IN NODULAR CAST IRON BY SPM

The nodular cast iron samples were prepared with the normal nodularizing process, in which the important antinodularizing elements Pb, Bi and Al were added respectively in order to research the influence of them on the nodularization of the graphites. The nodular graphites were extracted from the nodular cast iron by the electrolytic technique. The distribution of trace elements in nodular and deformed graphite were measured by Scanning Proton Microprobe (SPM). Most of the adding elements Pb, Bi and Al existed in matrix as impurities, a part of them intruded into the nodular graphites. A new suggestion of Ti antinodularizing properties had been proposed. The influence of Pb, Bi and Al on the nodularization was indirectly performed through Ti. Therefore, Ti is one of the most important antinodularizing elements.     

萃取光度法测定辐照后元件的希土总量

研究了从HNO_3介质中用TOPO预分离铀、钚及PMBP萃取,HNO_3体系反萃分离希土的条件。应用偶氮氯膦-mA显色测定希土总量。提出了用草酸铵抑制钇的吸光度的合适条件,使钇与铈组元素的吸光度趋于一致。用本法实测了辐照后元件中的希土总量并由此计算了元件的燃耗值。其结果与质谱法、放化法所得结果在±2%内符合。本文提供了一个化学法测定燃耗的方法。     

冠醚-1,2-二氯乙烷在苦味酸体系中对轻希土元素的萃取

本文在文献[1]的基础上,研究了二环己基-18-冠-6(DC18C6)和二环己基-15-冠-5(DC15C5)在苦味酸体系中对La~(3+),Ce~(3+),Pr~(3+),Nd~(3+),Sm~(3+),Eu~(3+),Gd~(3+)七个轻希土元素的萃取,求得了萃合常数和萃合物在有机相中的离解常数,并测定了苦味酸在水相对七个希土元素的一级络合常数。     

HDEHP萃取镓的机理

引言镓与伴生元素铝、铁和铜的分离可用20%TBP-二甲基溶液从盐酸或硫酸溶液中萃取镓来实现,萃取效率可高达99.9%以上,但必须在浓盐酸条件下进行。Morris用中性磷类萃取剂TBP从盐酸溶液中萃取氯化镓时,观察到溶液中酸度为0.2—0.6 mol/l时,镓     

协同萃取体系的研究——Ⅱ.DMHMP和HEHEHP协同萃取UO_2(NO_3)_2的机理

本文研究了甲基膦酸二(1-甲庚)酯(DMHMP)和2-乙基已基膦酸单(2-乙基己基)酯(HEHEHP)协同萃取硝酸钠酰。用斜率法测得协萃络合物的组成为UO_2(NO_3)(HA_2)·DMHMP。在20℃时(离子强度为0.5)协萃反应平衡常数1gβ_(12)=4.95。并求得了热力学函数ΔH、ΔZ和ΔS分别为—2.50×10~4J·mol~(-1)、-2.75×10~4J·mol~(-1)和8.61J·mol~(-1)·K~(-1)。依据锥角堆积模型讨论了协萃反应机理。     

用P507-磺化煤油溶液从硝酸溶液中萃取分离镅(锔)与稀土元素

测定了镅(锔)和轻稀土元素(La、Ce、Pr、Nd、Sm)在P507-磺化煤油和硝酸溶液中的分配比,确定了它们被萃取能力的顺序为:La相似文献   

溶剂萃取分离-α计数法分析钚的价态

用0.1mol/l D_2EHPA-5%TIOA-二甲苯从1.5mol/l硝酸中萃取Pu(IV)和Pu(VI),Pu(Ⅲ)留在水相。用0.1mol/l草酸将Pu(IV)反萃,Pu(VI)留在有机相。将分开的不同价态的钚定量取样、制源后进行α计数测量,便分析出它们在原样中的浓度。当源盘中钚量达1.5μg时,相对标准偏差为±4%。该方法与恒电位库仑法的相对偏差约为2%。     

二氯苯基二硫代膦酸萃取Am~(3+)和三价镧系元素的研究

研究了二氯苯基二硫代膦酸 (DCPDTPI)对示踪量Am3+ 和Eu3+ 的萃取。实验结果表明 ,此萃取剂优先萃取Am3+ ,当萃取剂浓度为 0 1mol/L ,pH =2 73时 ,最大的分离因数β(Am3+ /Eu3+ ) max=8。用ICP MS法同时测定了DCPDTPI对除钷以外的所有镧系元素的萃取分配比 ,并计算了Am3+ 与这些元素的分离因数     

不对称荚醚萃取铀(Ⅵ)和稀土(Ⅲ)的研究

研究了不对称荚醚N，N'-二甲基二己基-3-氧戊二酰胺(DMDHGA)、N，N’-二甲基二辛基-3-氧戊二酰胺(DMDOGA)、N，N’-二甲基二月桂基-3-氧戊二酰胺(DMDLGA)和N，N’-二甲基二己基-3，6-二氧辛二酰胺(DMDHOA)在HNO3介质中对铀(Ⅵ)、稀土(Ⅲ)和锶(Ⅱ)的萃取行为。结果表明，随着酰胺官能团氮原子上烷基链增大，不对称荚醚萃取性能下降，与铀(Ⅵ)形成的萃合物在烷烃稀释剂中的溶解性增加。分别使用正十二烷、异辛烷和煤油作稀释剂时，DMDOGA萃取铀(Ⅵ)均出现第三相，而DMDHGA，DMDHOA和DMDLGA萃取时均不出现第三相。DMDHGA萃取铀(Ⅵ)和锶(Ⅱ)的分配比及铀(Ⅵ)与锶(Ⅱ)之间的分离系数均比对称荚醚N，N，N’，N'-四丁基-3-氧戊二酰胺(TBGA)的大，有利于铀(Ⅵ)与锶(Ⅱ)的分离。DMDLGA与铀(Ⅵ)生成1：1型萃合物；而DMDLGA和DMDOGA与混合稀土(Ⅲ)(组成以氧化物计为27％La2O3，51％CeO2，6％Pr6O11,16％Nd2O3)生成1：2型萃合物。     

二氯苯基二硫代膦酸萃取Am^3＋和三价镧系元素的研究

研究了二氯苯基二硫代膦酸（DCPDTPI）对示踪量Am^3 和Eu^3 的萃取,实验结果表明,此萃取剂优先萃取Am^3 ,当萃取剂浓度为0．1mol/L,pH=2.73时,最大的分离因数β（Am^3 /Eu^3 )max=8。用ICP－MS法同时测定了DCPDTPI对除钷以外的所有镧系元素的萃取分配比,并计算了Am^3 与这些元素的分离因数。     

色层分离—原子吸收／火焰光度法测定UO2中痕量碱金属元素

色层分离-原子吸收/火焰光度法是为分析测定动力堆元件、UO_2粉末和芯块中痕量Li、Na、K和Cs而研究建立的标准分析方法。样品用HNO_3溶解后调成5.5 mol·l~(-1)HNO_3介质,通过TBP色层柱,将待测元素与U分离。分别用FAAS和TAES法测定淋洗液中的Li、Na、K和Cs。取样量为0.5g时,4个元素测定下限均为2×10~(-6)。K和Na含量为10×10~(-6)、Li和Cs为5×10~(-6)时,加入回收率为96%-106%。相对标准偏差在7%以内。