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双语推荐：Rn源

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^227Ac是制备^219Rn放射源的最佳母体。论文介绍了对从铀矿石中提取的^227 Ac进行放射性纯度鉴定的方法。通过对^219 Rn子体^211 Pb的相对测量及^219 Rn的干扰核素^222 Rn、^220 Rn的定量测量来鉴定产品^227 Ac的放射性纯度，^227 Ac产品中^222 Rn、^220 Rn的含量少于0．2％，^227 Ac的放射性纯度能达到99．8％以上。
227 Ac is the most appropriate parent nuclide to produce a solid 219 Rn source.The paper describes methods to determinate the radiochemical purity of 227 Ac ext-rated from uranium ore .The radiochemical purity of 227 Ac is determined by relative measurement of 211 Pb and quantitative measurement of 222 Rn、220 Rn.The re-sults show that the content of 222 Rn、220 Rn in 227 Ac product is lower than 0.2%, and the radiochemical purity of 227 Ac is up to 99 .8%.

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对利用从铀矿石中提取得到的227Ac制备的固体219Rn源进行了γ能谱分析,确定了227Ac的4个子体核素227Th、223 Ra、219Rn和211 Bi的活度,并分析了能对219Rn造成干扰的222 Rn、220Rn母体核素226 Ra、224 Ra的活度。待227 c及其子体达到放射性平衡后,通过测量227Th的235.97、256.25keV,223 Ra的154.21keV,219Rn的401.81keV,211Bi的351.059keV共5条γ射线,最终确定固体219Rn源中227Th、223 Ra、219Rn和211Bi的活度为(1 069±3)、(1 079±5)、(1 095±13)、(1 096±14)和(11 089±4)Bq,固体219Rn源的平均活度为(1 093±8)Bq;通过测量224 Ra子体212Pb的238.632keV、208 Tl的583.191keVγ射线以及226 Ra子体214 Bi的609.312、1 120.287keVγ射线得到226 Ra与224 Ra的平均活度分别为5.12Bq及0.433Bq,远低于固体219Rn源的平均活度,说明固体219Rn源放射性纯度较高。以上结果表明,此源有望制成标准固体219Rn源以用于延迟符合法测223 Ra、227Ac装置的刻度。
Radioactivity purity of the solid 219 Rn source made using 227 Ac extracted from uranium ore were determined by γ‐spectrometry .The activities of 227 Th ,223 Ra ,219 Rn and 211 Bi produced by the decay of 227 Ac and the contents of 226 Ra ,224 Ra w hich generates 222 Rn ,220 Rn to affect the purity of actinide in this source were analyzed after 227 Ac in radioactive equilibrium with its daughter nuclides . The γ‐ray energy used for the determination of these daughter nuclides of 227 Ac are 235.97 ,256.25 keV for 227 Th , 154.21 keV for 223Ra ,401.81 keV for 219Rn ,and 351.059 keV for 211Bi .Through the analysis ,the results are acquired that their activities are (1 069 ± 3 ) , (1 079 ± 5 ) , (1 095 ± 13) ,(1 096 ± 14) and (11 089 ± 4) Bq respectively ,and the average activity of solid 219 Rn source is (1 093 ± 8) Bq .The activities of 226 Ra and 224 Ra in this source are 5.12 Bq and 0.433 Bq respectively by the γ‐ray energy as follows :238.632 keV of 212Pb,583.191

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介绍了一种测量低浓度220 Rn的方法---时间间隔分析方法。220 Rn原子发生衰变发射α粒子并产生216 Po时，在很短时间内，216 Po衰变（半衰期0.145 s）又发射α粒子。多时间分析方法就是对2个连续发射的α粒子的时间间隔进行分析，使220 Rn从222 Rn中分辨出来。本实验通过卢卡斯氡探测器（FD125）对10 Bq的220 Rn标准源进行流气式测量。当222 Rn活度小于10倍左右220 Rn活度时，计数率控制在60 min-1以内，时间分辨率设置为1 ms ，测量时间为10 h ，测量结果的相对偏差在7％内。
T his paper introduced a measurement method of low concentration 220 Rn-time interval analysis (TIA) method .In the short time after the alpha particle emitted at the decay of a 220 Rn atom an alpha particle from the decay of 216 Po (half life 0.145 ) follows .The multi-time analysis method is based on the analysis of the emitting time interval between the two successive alpha particles ,which can be used to discriminate the 220 Rn from 222 Rn .A flow through Lucas cell (FD125) was used to measure 10 Bq standard 220 Rn source .When the 222 Rn activity is less than 10 times the 220 Rn activity , count rate is controlled within 60 min-1 ,the time resolution is set to 1 ms and the meas-uring time is 10 h ,and the relative deviation of the results is within 7% .

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讨论多时间间隔分析方法(又称TIA方法)和延迟符合法同时测量10 Bq的220Rn标准源,两者为相同实验平台,采用卢卡斯氡探测器(FD-125)对220Rn标准源进行流气式测量,改变软件实现两种不同数据处理方法.实验结果表明,多时间间隔分析法在测量低浓度220Rn时更加准确.
This article focuses on the time interval analysis( TIA method) method and de_lay coincidence method at the same time measuring 10 Bq of 220 Rn standard source,both for the same experimental platform and conditions. Lucas detector(FD_125) was applied to flow_through measure the standard 220 R,two different data processing methods were estab_lished by changing the software. It can be seen,the time interval analysis is more accurate than delay coincidence for measuring the low 220 Rn.

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延迟符合法测量220 Rn和219 Rn是间接测量天然水中224 Ra和223 Ra的方法,能提供河口海洋混合区海底地下水流出情况及水与土壤相互作用的示踪信息。在实际测量计算中会用到Moore偶然符合修正方法,然而研究发现,Giffin和Moore方法还存在某些不完善之处。本文在Moore和Giffin方法的基础上,对Moore方法进行了改进（简称方法1）,同时提出了新的偶然符合修正公式（简称方法2）;构建实验装置分别测量低活度222 Rn、220 Rn、219 Rn源及220 Rn和219 Rn混合源,对偶然符合修正公式进行比对实验验证。结果表明,总计数率小于70min-1时,本工作提出的两种方法在准确度和误差方面均较Moore和Giffin方法有所改善。
T he delay coincidence measurement of 220 Rn and 219 Rn has been proved to be a valid indirect method for measuring 224 Ra and 223 Ra extracted from natural water ,which can provide valuable information on estuarine/ocean mixing , submarine groundwater discharge ,and water/soil interactions .In practical operation chance coincidence correc-tion must be considered ,mostly Moore’s correction method ,but Moore’s and Giffin’s methods were incomplete in some ways .In this paper the modification (method 1) and a new chance coincidence correction formula (method 2) were provided . Experiments results are presented to demonstrate the conclusions .T he results show that precision is improved w hile counting rate is less than 70 min-1 .

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氡及其子体是人类所受到的来自天然辐射的主要辐射照射源，近年来我国掺渣建材的广泛使用使得室内氡平均水平有所提高。建筑工程上的防护和减缓是降低室内氡的关键及低成本方法。GB50325-2010首次给出了建材氡析出率检测方法标准。其中主动抽气采集型测定建筑材料表面氡析出率步骤要求抽气采集容器的平均高度为0．5 m。论文通过数值模拟得到较高的高度有利于减少^222 Rn测量中^220 Rn的干扰，而且可以降低采气容器内的^222 Rn浓度，减少反扩散效应。因此222 Rn的析出率可以利用低成本的仪器和简洁的计算得到。
The main radiation exposure from natural radiation sources for human are Radon and its daughters .In recent years , the widespread use of building materials mixed with slag make the average indoor radon level in -creased .The protection and mitigation on construction work are the key and low -cost method to reduce indoor radon.The average height of collection chamber is 0.5m required by the procedure of active drawing air type for measuring radon exhalation rates from building materials surface defined by GB 50325-2010 .In this paper , we find that higher height of the collection chamber can reduce the 220 Rn interference in 222 Rn measurements by nu-merical simulation;and also can decrease the 222 Rn concentration in the collection chamber to reduce the effect of back-diffusion.222 Rn exhalation rate can be obtained by low -cost equipment and simple calculations .

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It is well known that the commutator Tb of the Calder′on-Zygmund singular integral operator is bounded on Lp(Rn) for 1 p +∞if and only if b∈BMO [1]. On the other hand, the commutator Tb is bounded from H1(Rn) into L1(Rn) only if the function b is a constant [2]. In this article, we will discuss the boundedness of commutator of certain pseudo-differential operators on Hardy spaces H1. Let Tσbe the operators that its symbol is S01,δwith 0≤δ 1, if b∈LMO∞, then, the commutator [b, Tσ] is bounded from H1(Rn) into L1(Rn) and from L∞(Rn) into BMO(Rn); If [b, Tσ] is bounded from H1(Rn) into L1(Rn) or L∞(Rn) into BMO(Rn), then, b∈LMO_(loc).
It is well known that the commutator Tb of the Calder′on-Zygmund singular integral operator is bounded on Lp(Rn) for 1

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介绍了使用流气式固体220Rn源向闪烁液中加载示踪核素212Pb的实验方法.研究了不同温度、气体流率下,闪烁液对212^Pb的加载效率的变化情况.为开展江门中微子闪烁液纯化验证实验提供放射性核素加载的方法,为放射性核素加载实验条件的选择提供了依据.
This paper describes the experimental method of using the flow-through solid220 Rn source to add tracer nuclide212 Pb to liquid scintillator. It has been studied for the chan-ges of the efficiency of liquid scintillator adding212 Pb under different temperature and flow-rate. For carrying out liquid scintillator purified efficiency verification test, it provides a method to add radionuclide to liquid scintillator in the Jiangmen Underground Neutrino Ex-periment. And it provides the basis for choosing the experimental conditions of radionuclide addition.

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首先证明了Littlewood-Paley算子与Lipschitz函数生成的向量值多线性Littlewood-Paley交换子|g bΧ|r是从Lp(Rn)到Triebel-Lizorkin空间﹒Fmβ,∞p(Rn)有界的,然后证明了交换子|g bΧ|r是从Lp(Rn)到Lq(Rn)有界的.
In this paper , we prove the vector-valued multilinear commutator | gbΨ | r is bounded from Lp ( Rn ) to Triebel -Lizorkin spaceFmβ,∞p (Rn ) ,which is generated by Littlewood - Paley operator and Lipschitz function .Then we prove the vector-valued multilinear commutator Fmβ,∞p ( Rn ) is bounded from Lp ( Rn ) to Lq ( Rn ) .

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利用E－凸集和E－凸函数的定义，研究了E－凸函数的性质，给出并证明了E－凸函数的一个充分必要条件：设集合M炒Rn ，映射E：Rn→Rn ，函数f：Rn→R和g：R→R，且g（ t）＝f（ x＋td），（其中d∈Rn），则f是E－凸函数当且仅当g是E－凸函数。并对E－凸函数的若干特征进行了研究分析，得出了E－凸函数的判别条件及其性质。
The properties of E-convex function were studied using the definition of E-con-vex sets and convex function.A necessary and sufficient condition of E-convex function was proved:let M炒Rn, mapping E:Rn→Rn, function f:Rn→R and g:R→R function, and g(t)=f(x+td) (where d∈Rn), then f is a E-convex function if and only if g is a E-convex function.And several features of E-convex functionwere studied and analyzed.The criteri-ons and properties of E-convex function were obtained.

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