367 resultados para radioactive C-9-ion beam
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稀土有机碳σ-键配合物和氢化物不仅可以催化许多有机反应,而且还可以催化极性单体与非极性单体的聚合.作为稀土有机碳σ-键配合物与氢化物的前体,双配稀土氯化物(C<,9>H<,7>)<,2>LnCl一直是稀土有机化学中研究的热点.1.合成了一系列双配(四氢糠基茚基)稀土氯化物(C<,4>H<,7>OCH<,2>C<,9>H<,6>)<,2>LnCl(Ln=La,Pr,Nd,Sm,Gd,Dy,Y,Ho,Er,Yb,Lu).除了Pr以外,所有化合物的晶体结构都被X-射线衍射表征.2.合成并用X-衍射表征了3-(2-吡啶甲基)茚基锂(C<,5>H<,4>NCH<,2>C<,9>H<,6>)Li(THF)<,2>的晶体结构.3.合成了双配[3-(2-吡啶甲基)茚基]稀土氯化物(C<,5>H<,4>NCH<,2>C<,9>H<,6>)<,2>LnCl(Ln=Sm,Nd),并得到了配合物Nd的晶体结构.4.用二碘化钐(镱)与3-(2-吡啶甲基)茚基锂反应合成了二价双配[3-(2-吡啶甲基)茚基]稀土配合物(C<,5>H<,4>NCH<,2>C<,9>H<,6>)<,2>Ln(Ⅱ)(THF)(Ln=Sm,Yb).5.在用无水氯化稀土YbCl<,3>与3-(2-吡啶甲基)茚基锂反应合成双配[3-(2-吡啶甲基)茚基]稀土氯化物时,由于发生了还原反应,得到了二价双配[3-(2-吡啶甲基)茚基]镱化物(C<,5>H<,4>NCH<,2>C<,9>H<,6>)<,2>Yb(Ⅱ)(THF).6.二价双配[3-(2-吡啶甲基)茚基]稀土配合物(C<,5>H<,4>NCH<,2>C<,9>H<,6>)<,2>Ln(Ⅱ)(THF)(Ln=Sm,Yb)对已内酯具有很好的催化聚合活性.聚合反应可控,并具有活性聚合的特征.
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本工作用固相反方法、以炭保护或在N_2-H_2还原气氛中,两次灼烧,合成了一系列烯土取代的卤磷酸盐发光体,其反应是M_2~ICO_3 + M_3~(II)(PO_4)_2 + M_2~(III)O_3 + (NH_4)_2HPO_4 + M~(II)F_2 → M_x~IM_(10-2x)~(II)M_x~(III)(PO_4)_6F_2 + NH_3 + H_2O式中:M~I = Li~+, Na~+, K~+; M~(II) = Ca~(2+), Sr~(2+); M~(III) = Y~(3+), La~(3+), Gd~(3+); X = 0.5, 1, 2, 3。通过X-射线分析法和以Eu~(3+)作为荧光离子探针方法确定了样品的物相和晶体结构,表明它与M_(10)~(II)(PO_4)_6F_2同属六方晶系(Pb_3/m)。并用图解外推法求得样品的晶胞参数a和c分别为9.41和6.89 A。在研究了M~I, M~(II)和M~(III)为不同阳离子,X为不同值时,取代物的物相和结构变化以及对Ce~(3+)发光和能量传递影响规律的基础上,以Na_2Ca_6La_2(PO_4)_6F_2为基本体系比较详细地研究了Ce~(3+)的发光,Ce~(3+)-Mn~(2+), Ce~(3+)-Re~(3+) (Re~(3+) = Pr~(3+)、Nd~(3+)、Sm~(3+)、Tb~(3+)、Dy~(3+)、Tm~(3+)、Ho~(3+)、Er~(3+))以及Ce~(3+)-Mn~(2+)-Re~(3+) (Re~(3+) = Dy~(3+), Nd~(3+))的能量传递。实验发现,Na_2Ca_6La_2(PO_4)_6F_2:Ce~(3+)是较强的紫外光发射体,发射谱带是由338和358nm两个宽带峰组成的,相应于~2D-~2F_(5/2)和~2D-~2F_(1/2)跃迁。发射强度和~2D-~2F_(6/2),~2D-~2F_(7/2)两种辐射跃迁几率相对大小与温度,Ce~(3+)的浓度有关;F~-含量对发射强度也有强烈的影响。我们认为,浓度和温度的影响是由于Ce~(3+)-Ce~(3+)的能量迁移作用。实验发现,Ce~(3+)能有效地敏化Mn~(2+)的发光,得到高效的黄色荧光发射体。Ce~(3+)对Re~(3+)的作用可以分为三类:A). Ce~(3+)-Sm~(3+)、Tb~(3+)、Dy~(3+)、Tm~(3+);B).Ce~(3+)-Nd~(3+),Pr~(3+);C). Ce~(3+)-Ho~(3+), Er~(3+)。在A,B类型中,Ce~(3+)能有效地敏化这些稀土离子,但能量传递效率(η_T)_A > (η_T)_B。在Ce~(3+)-Ho~(3+)、Ce~(3+)-Er~(3+)类型中,Ho~(3+)、Er~(3+)不产生可见辐射,Ce~(3+)的发射强度也显著降低。在Ce~(3+)-Mn~(2+)-Re~(3+)三元中心体系中,Ce~(3+)的能量可直接传递给Mn~(2+)和Re~(3+)中心,还可通过Ce~(3+)-Mn~(2+)-Re~(3+)的途径传递。通过研究中心离子的浓度效应,温度效应、测定激发光谱、荧光光谱、荧光衰减曲线的荧光寿命,能够证实:在Ce~(3+)-Mn~(2+)、Ce~(3+)-Re~(3+)、Ce~(3+)-Mn~(2+)-Re~(3+)的能量传递属于无辐射共振传递相互作用类型。符合M. Yokata等人提出的偶极-偶极相互作用扩散限制传递历程。我们还利用Ce~(3+)、Ce~(3+)-Mn~(2+)、Ce~(3+)-Re、Ce~(3+)-Mn~(2+))-Re~(3+)激活体系中Ce~(3+)的发射强度和荧光寿命等数据计算了Ce~(3+)的能量传递效率。发现两种结果相差较大,为了准确地表达Ce~(3+)的敏化效果,在分析上了产生这种误差的原因后,提出了两种传递效率表示式(η_f, η_R)。
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本文叙述了2.4-二甲基戊二烯基稀土金属有机化合物的合成并通过元素分析,红外光谱、核磁共振谱及质谱的鉴定。测定了Gd(2.4-GH_(11))_3的单晶结构,此外还合成了(2.4-GH_(11)K.TMEDA及K_2C_8H_8·3THF并也测定了它们的晶体结构。在所合成化合物的红外光谱中,没有属于C=C双键的吸收峰,表明分子中配位体以η~5形式的大π键体系与稀土金属离子结合,在Ln(2.4-GH_(11))_2Cl·TMF和Ln(2.4-GH_(11))Cl_2·GH_THF的红外光谱中,于1060波数附近出现一强而宽的吸收峰,即化合物中有四氢呋喃分子络合。化合物的室温NMR谱有四个吸收峰,2.4-二甲基戊二烯配位体可能为η~5平面∪或W构型。化合物的水解'H-NMR谱与质谱都证实水解产物为2.4-二甲基-1.3-戊二烯。它是-2.4二甲基戊二烯阴离子水解所得的唯一产物,它表明化合物中的配位体确为2.4-二甲基戊二烯阴离子。(2.4-GH_(11))_2Cl·TMDA配合物晶体结构是应用低温X-射线衍射技术用Nicolet R_3 M/E型四园衍射仪LT-1低温装置并利用重原子法测定的最小二乘法精修至收敛时的一致性因子R=0.055. Rw=0.057。晶体属单斜晶系P21/n空间群。晶胞参数a=11.322(4)A, b=9.242(3)A, c=15.956(5)A. β=106.70(3)分子中2.4-二甲基戊二烯阴离子呈平面∪构型。钾离子与四甲基乙二胺二啮体结合形成的络合阳离子和2.4-二甲基戊二烯阴离子相间排列形成无限链状结构分子。2.4-二甲基戊二烯阴离子的C-C键长明显分为中间与外端C-C键两组。外端组C-C键双性质较强键长较短。表明C3具有负电荷的共振杂化体贡献较大。分子中K-C键最短的是K-C(1.5)。而不是具有较多负电荷的C3-K键。这可能是由于几何因素造成的。K_2C_8H_8·3THF的晶体结构是采用与前者相同的方法测定的。它属三斜晶系,PT空间群,晶胞参数a=10.263(3)A, b=13.157(4)A, c=9.443A, α=87.51(2)°, β=114.93(2)°, γ=76.81(2)°. V=1111.6A, R=0.051. 晶体中负二价的环辛四烯阴离呈平面构型,具有中心对称性,两侧与两中心对称相关的钾离子连接,相邻的非等效的钾离子间通过两四氢呋喃分子的氧原子相连接,从而形成了无限链状结构的分子。环辛四烯反映了Huckel的4n+2芳香性规则。该结构的特别之处在于四氢呋喃分子的氧原子以桥键形式与两个钾离子同时连接。而这种形式的桥键在其它化合物中似还未发现。Go(2.4-GH_(11))_3的晶体结构亦是采用与前述相同的方法测定的。其晶体为三斜晶系,PT空间群,晶胞参数a=12.541A, b=12.853A, c=8.432A, α=91.44°, β=108.61°, γ=117.97°, V=112.54A~3. 结构测定表明,Gd(2.4-GH_(11))_3分子具有C_3h对称性。三个配位体阴离了的九个带负电荷的碳原子近似以三帽三角棱柱形式与钆离子配位。分子中2.4-二甲基戊二烯阴离子的C-C键长-亦分为而组。外端C-C键较中间C-C键强,键长较短,亦表明C3具有较多的负电荷。2.4-二甲基戊二烯阴离子本身近似呈平面∪构型。C2,C4偏离由C1 C3 C5三碳原子构成的平面0.067A。方向上远离中心钆离子。可能在此以离子性为主的化合物中,钆离子与不带电荷的C2 C4间的相互作用有些排斥性质。与Nd(2.4-GH_(11))_3不同的是,在Gd(2.4-GH_(11))_3分子中,Gd-(C(1,5)键最短,而不是Gd-C(3)键。这可能是由于钆离子的半径较小,化合物的空间位阻效应较大所致。
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本论文包括三个部分的内容,第一部分研究了Y-Ba-Cu-O材料中,钙、钾、氟离子的掺入对材料结构和电、磁学性质的影响。1、在Y_(1-x)Ca_xBa_2Cu_3O_(7-y)系列中,当x ≤ 0.15时,钙离子进入了YBa_2Cu_3O_(7-y)晶格中钇离子的位置,使晶胞参数略为增大,但没有引起正交 → 四方相变。钙离子渗入导致123相中Cu~(3+)含量上升,同时材料的监界超导转变温度下降。因此,Cu~(3+)含旱管高可能是对超导电性不利的。由于钇离子位置紧邻着Cu(2)-O平面而与Cu(1)-O链相隔较远。因此,钇离子被钙离子替代时主要影响了Cu(2)-O平面的性质。少量钙离子的渗入即明显影响材料的超导电性,这说明Cu(2)-O平面的性质与超导电性密切相关,并可能起着关键的作用。2、在Y(Ba_(1-x)Ca_x)_2Cu_3O_y系的研究中,当x = 1,YCa_2Cu_3O_y是一个单一的化合物,文献未见报道,本文研究了它的结构,电学性质与热学性质,确定它的结构属正交晶系,a = 5.286 A、b = 7.636 A、c = 9.286 A。热分析表明YCa_2Cu_3O_y在1080 ℃分解,分解前于380 ℃ 和608 ℃出殃失氧现象。这个化合物是黑色n型半导体。室温电阻率1.2 * 10~5Ω·cm。与热分析中的失氧温度相对应,lnρ-1/T曲线上在370 ℃、620 ℃ 出现两个转折点。3、在Y-Ba-Cu-O材料中渗入钾离子能细化材料晶粒,降低超导转变宽度,提高零电阻温度,但由于KOH、K_2CO_3等强吸湿性杂质的存在也降低了材料的稳定性。4、在Y-Ba-Cu-O材料中间时掺入钾和氟离子时,材料的超导电性的变化与仅掺钾时相似。这种变化可能主要是钾离子的影响造成的。第二部分中,我们研究了Ca-Sr-Ca-O系的相图和新化合物Sr_3Cu_5O_(8+x)、CaSrCu_3O_(5+x)的结构和电学性质。在第三部分中,广泛研究了组成为Bi_tSr_vCa_wCu_zO_y超导材料的制备,结构和超导电性。铋系超导材料的形成貌与YBa_2Cu_3O_y材料有较大差异,前者是片状层叠的晶粒堆积而成,后者是球状小颗粒堆积而成的。我们合成的材料最高起始转变温度124K,最高零电阻温度112K,与国际上已达到的最高Tc值一致。Jc值达到131A/cm~2。
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介绍了一种利用离子束外延(Ion-beam Epitaxy, IBE)技术制备生长高纯稀土功能薄膜的新方法. 以纯度要求不高的低成本稀土氯化物为原材料来产生大束流稀土元素离子, 通过准确控制双束合成或单束浅结注入掺杂的同位素纯低能离子的能量、束斑形状、沉积剂量与配比及生长温度, 在超高真空生长室内实现了稀土功能薄膜的高纯生长和低温优质外延. 文中除了对新方法的技术特点、实施方式和应注意的关键技术进行了阐述, 还结合CeO2, Gd2O3, GdxSi1-x等薄膜的制备研究, 讨论了离子的束流密度、剂量配比、能量和生长温度等生长参数对成膜质量的影响.
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A windowed very-small-aperture laser 9VSAL0 source for use in high-resolution near field optical data storage is fabricated. The windowed regions are introduced to avoid shorting the pn junction with metal coating and suppress the COD effect. It facilitates producing VSAL by simplified technology and improves the laser performance. A VSAL with 400nm small sperture is demonstrated by focused ion beam (FIB0 and the output power is 0.3mW at 31mA.
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Silicon-on-insulator (SOI) has been recognized as a promising semiconductor starting material for ICs where high speed and low power consumption are desirable, in addition to its unique applications in radiation-hardened circuits. In the present paper, three novel SOI nano-layer structures have been demonstrated. ULTRA-THIN SOI has been fabricated by separation by implantation of oxygen (SIMOX) technique at low oxygen ion energy of 45 keV and implantation dosage of 1.81017/cm2. The formed SOI layer is uniform with thickness of only 60 nm. This layer is of crystalline quality. and the interface between this layer and the buried oxide layer is very sharp, PATTERNED SOI nanostructure is illustrated by source and drain on insulator (DSOI) MOSFETs. The DSOI structure has been formed by selective oxygen ion implantation in SIMOX process. With the patterned SOI technology, the floating-body effect and self-heating effect, which occur in the conventional SOI devices, are significantly suppressed. In order to improve the total-dose irradiation hardness of SOI devices, SILICON ON INSULATING MULTILAYERS (SOIM) nano-structure is proposed. The buried insulating multilayers, which are composed of SiOx and SiNy layers, have been realized by implantation of nitride and oxygen ions into silicon in turn at different ion energies, followed by two steps of high temperature annealing process, respectively, Electric property investigation shows that the hardness to the total-dose irradiation of SOIM is remarkably superior to those of the conventional SIMOX SOI and the Bond-and-Etch-Back SOI.
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本学位论文报道了西藏产三种藏族传统植物药材的化学成分研究。论文由四章组成,前三章是实验部分,分别报道了尼泊尔黄堇(Corydalis hendersonii Hemsl.)、藏波罗花(Incarvillea younghusbandii Sprague)和全缘叶绿绒蒿(Meconopsis interifolia Franch.)的化学成分研究结果。从这三种青藏高原药用植物中共分离鉴定出33 个化合物,其中1 个是新化合物。第四章概述了罂粟科紫堇属植物的化学和药理研究进展。 第一章为尼泊尔黄堇的化学成分研究。通过正、反相硅胶柱色谱等分离方法从药用植物尼泊尔黄堇的地上部分共分离纯化得到12 个化合物。运用MS、1H-NMR、13C-NMR、DEPT、HMBC、NOESY 等现代波谱学方法将它们的结构鉴定为:刺罂粟碱(1) , 普托品(2) , 新那亭(3) , 斯可任(4) , tetrahydrothalifendine (5) ,9-methyl-decumbenine C (6),tetrahydroberberrubine (7),隐品碱(8),α-别隐品碱(9),6,7-methylenedioxy-1(2H)-oxoisoquinolinone (10),6-丙酮基-5,6 -二氢血根碱(11)和β-谷甾醇(12)。其中化合物6 为新化合物,为首次发现的分子骨架上C-9 位连有甲基的苯肽异喹啉类型生物碱。另外,除化合物1 和2 外,其它9 个生物碱(3~11)均为首次从该种植物中分离得到。同时,我们还对对尼泊尔黄堇中的总生物碱进行了串联质谱分析。 第二章为藏波罗花的化学成分研究。从该药用植物的地上部分共分离得到16个化合物,通过理化常数和波谱数据鉴定为:异佛手柑内酯(1),6-甲氧基当归素(2),欧前胡素(3),花椒毒内酯(4),珊瑚菜素(5),水合氧化前胡素(6),rivulobirin A (7),齐墩果酸甲酯(8),咖啡酸甲酯(9),银桦酸(10),(D)-boschniakinic acid (11),对羟基苯甲酸(12) , tert-O-β-D-glucopyranosyl-(R)-heraclenol (13) , 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14),前胡苷V(15)和苯乙醇-O-β-D-吡喃葡萄糖-(1→2)-O-β-D-吡喃葡萄糖苷(16)。所有以上化合物均为首次从该种植物中分离得到。另外我们还首次对藏波罗花挥发油的化学成分进行了气相色谱-质谱(GC-MS)联用分析,共鉴定出39 个挥发性成分。 第三章为全缘叶绿绒蒿化学成分的分离鉴定。从传统藏药材全缘叶绿绒蒿地上部分共分离纯化出8 个化合物。通过理化常数和波谱数据将他们的结构分别鉴定为:去甲血根碱(1),β-谷甾醇(2),3-羟基-齐墩果烷-12(13)-烯-30-酸(3),6-丙酮基-5,6-二氢血根碱(4),木犀草素(5),胡萝卜苷(6),quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7)和普托品(8)。其中化合物1,4 和7 为首次从该种药用植物中分离得到。 第四章为综述,总结和归纳了近年来罂粟科紫堇属植物的化学和药理研究进展。 This dissertation consists of four parts. The first, second and third parts report the studies on the chemical constituents from the medicinal plants of Corydalis hendersonii, Incarvillea younghusbandii and Meconopsis interifolia. The forth part reviews the progress of the studies on Corydalis species. The first chapter is about the isolations and identifications of alkalids from the aerial parts of C. hendersonii which is a traditional Tibetan medicine to treat febrifuge, high blood pressure and hepatitis. A new isoquinoline alkaloid, 9-methyl-decumbenine C (6), together with ten known alkaloids, stylopine (1), protopine (2), canadine (3), scoulerine (4), tetrahydrothalifendine (5), tetrahydroberberrubine (7), cryptopine (8), α-allocryptopine (9), 6,7-methylenedioxy-1(2H)-isoquinolinone (10) and 6-acetonyl-5,6-dihydrosanguinarine (11), and β-sitosterol (12) were isolated. Their structures were elucidated by spectroscopic methods. Furthermore, the total alkaloids were analyzed by ESI-MSn. The second chapter is about the isolations and identifications of chemical constituents from the aerial parts of I. younghusbandii. Sixteen compounds were isolated and purified by normal and reversed phase silica gel column chromatography. By spectral analysis, there structures were identified as isobergapten (1), sphondin (2), imperatorin (3), xanthotoxin (4), phellopterin (5), heraclenol (6), rivulobirin A (7), methyl oleanolate (8), methyl caffeate (9), grevillic acid (10), (D)-boschniakinic acid (11), 4-hydroxybenzoic acid (12), tert-O-β-D-glucopyranosyl-(R)-heraclenol (13), 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14), decuroside Ⅴ(15), and phenylethyl-O-β-Dglucopyranosyl-(1→2)-β-D-glucopyranoside (16). All of these compounds were isolated from this plant for the first time.By the way, the chemical components of the essential oil from I. younghusbandii were analyzed by GC-MS for the first time. The third chapter is about the the isolations and identifications of the chemical constituents of M. interifolia. Eight compounds were isolated and identified as norsanguinarine (1), β-sitosterol (2), 3-hydroxyolean-12(13)-en-30-oic acid (3), 6-acetonyl-5,6-dihydrosanguinarine (4), luteolin (5), daucosterol (6), quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7) and protopine (8). The compounds 1, 4 and 7 were isolated from this herb for the first time. The last chapter is a review of the research progress of the studies on Corydalis species, which includes the chemical constituents in this genus and their pharmacology.
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Electron Cyclotron Resonance (ECR) ion source is regarded as the most efficient machine to produce stable multiple charge state ion beams. Because of the special characteristics, all-permanent magnet ECR ion sources have been widely adopted around the world to produce stable ion beams of multiple charge state with good repetition have been widely adopted around the world to produce stable ion beams of multiple charge state with good repetition and high duty factor for compact research platforms and ion beam implanters. In this paper, all-permanent magnet ECR ion sources developed at IMP are presented, and typical parameters and performances are discussed. The high charge state source, LAPECR2, is mainly used to produce intense high charge state ion beams, and the LAPECR1 source is designed to produce intense ion beams of medium and low charge state. An improved LAPECR1-M is specially designed to produce heavy metal ion beams of low charge state. These ECR ion sources have been adopted by different experimental terminals at IMP and, with their nice performance, many experimental studies could be possible. 中文文摘:ECR(电子回旋共振)离子源是产生稳定的强流多电荷态离子束流最有效装置。全永磁ECR 离子源因其独特的特点为很多中小型多电荷态离子束流实验平台与离子注入机等系统所采用,为后者产生重复性好、稳定性强的多电荷态离子束流。本文着重论述了中国科学院近代物理研究所研制的几台全永磁多电荷态ECR 离子源及其特性与典型性能,如能产生强流高电荷态离子束流的高性能全永磁离子源LAPECR2,能产生强流中 低电荷态离子束流的LAPECR1,能产生多电荷态重金属离子束流的LAPECR1-M 等。这些性能稳定的离子源为提高近代物理研究所相关试验平台的性能提供了关键的束流品质保障。
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首先介绍了重离子束治癌的特点及当前的技术进步, 着重讨论了放射性离子束(RIB)在肿瘤治疗上增添的优势, 详细叙述了在日本放射医学综合研究所(NIRS)重离子医用加速器(HIMAC)上旨在肿瘤治疗的放射性离子束 C 的实验研究, 包括束流产生、参数优化、深度物理剂量分布、细胞辐照后的存 9活效应以及 C 和 C 束的相对生物效率(RBE)比较. 最终结果: 在40 mm 厚铍靶、10 mm 厚铝降能器、 9 125%动量接收度时, 采用 430 MeV/u、1.8×109 粒子/s 的初试束 C, 得到的 C 束的产生率为 9.07×10?6, 12 9纯度为 82.88%, 采用点扫描技术时, 在直径为 10 mm 的中心面积内, 可获得均匀度为 89.6%的辐照场,这时在入口处的剂量率为0.5Gy/h. 在Bragg峰附近范围内的细胞存活实验中, C束的平均RBE为5.28, 9而 C 束的平均 RBE 为 2.93, C 束的 RBE 要比 C 束的高1.8 倍, 这显示 C 束在 Bragg 峰附近范围内, 12 9 12 9对细胞的杀伤力要比 C 强, 在肿瘤治疗上会更有效. 12
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DNA damage and cell reproductive death determined by alkaline comet and clonogenic survival assays were examined in Lewis lung carcinoma cells after exposure to 89.63 MeV/u carbon ion and 6 MV X-ray irradiations, respectively. Based on the survival data, Lewis lung carcinoma cells were verified to be more radiosensitive to the carbon ion beam than to the X-ray irradiation. The relative biological effectiveness (RBE) value, which was up to 1.77 at 10% survival level, showed that the DNA damage induced by the high-LET carbon ion beam was more remarkable than that induced by the low-LET X-ray irradiation. The dose response curves of '' Tail DNA (%)'' (TD) and "Olive tail moment" (OTM) for the carbon ion irradiation showed saturation beyond about 8 Gy. This behavior was not found in the X-ray curves. Additionally, the carbon ion beam produced a lower survival fraction at 2 Gy (SF2) value and a higher initial Olive tail moment 2 Gy (OTM2) than those for the X-ray irradiation. These results suggest that carbon ion beams having high-LET values produced more severe cell reproductive death and DNA damage in Lewis lung carcinoma cells in comparison with X-rays and comet assay might be an effective predictive test even combining with clonogenic assay to assess cellular radio sensitivity
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The main ion-beam acceleration facilities and research activities at the Institute of Modern Physics (IMP), Chinese Academy of Sciences are briefly introduced. Some of the biomedical research with heavy ions such as heavy-ion biological effect, basic research related to heavy-ion cancer therapy and radiation breeding at the IMP accelerators are presented.
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Some superconducting magnets research at IMP (Institute of Modern Physics, CAS, Lanzhou) will be described in this paper. Firstly, a superconducting electron cyclotron resonance ion source (SECRAL) was successfully built to produce intense beams of highly charged heavy ions for Heavy Ion Research Facility in Lanzhou (HIRFL). An innovation design of SECRAL is that the three axial solenoid coils are located inside of a sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28 GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6 T at injection, 2.2 T at extraction, and a radial sextupole field of 2.0 T at plasma chamber wall. Some excellent results of ion beam intensity have been produced and SECRAL has been put into operation to provide highly charged ion beams for HIRFL since May 2007. Secondly, a super-ferric dipole prototype of FAIR Super-FRS is being built by FCG (FAIR China Group) in cooperation with GSI. Its superconducting coils and cryostat is made and tested in the Institute of Plasma Physics (IPP, Hefei), and it more 50 tons laminated yoke was made in IMP. This super-ferric dipole static magnetic field was measured in IMP, it reach to the design requirement, ramping field and other tests will be done in the future. Thirdly, a 3 T superconducting homogenous magnetic field solenoid with a 70 mm warm bore has been developed to calibrate Hall sensor, some testing results is reported. And a penning trap system called LPT (Lanzhou Penning Trap) is now being developed for precise mass measurements.
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利用重离子辐照技术对甜高粱种子进行不同剂量的诱变处理,并分析辐照后代的农艺性状、生理生化特性及基因组DNA的多态性差异,旨在选育出含糖量高、生物量高及抗逆性强的新品种,为发展生物质燃料乙醇产业提供优质的原料,并阐明重离子对甜高粱的诱变机理。主要结果如下: 1.甜高粱在田间的存活曲线表现为“类马鞍型”,随着辐照剂量的增加,其存活率先降后升再下降。 2.筛选出株高、单秆重、糖锤度、早熟型、茎粗等突变类型的材料,尤其是80Gy辐照剂量下从BJ0602中得到的早熟突变材料KFJT-1,生育期缩短了20天左右。 3.和未辐照株KFJT-CK相比,辐照突变株KFJT-1的萌芽指标表现为极显著差异(p<0.01),其发芽势、发芽指数、活力指数和子叶长度、胚根鲜重及子叶鲜重分别下降了24%、12.69%、0.8108%和15.32%、76.27%、27.08%。 4. 利用RAPD技术对不同剂量的辐照处理检测出的多态性差异表明,不同剂量的碳离子束辐照后,不同辐照剂量对应的5种处理材料的DNA突变率分别0%、11.4%、12.2%、18.7%和17.7%。 重离子辐照可引起甜高粱各个方向的突变,有些突变材料生物量和含糖量均高,而有些突变材料表现出生长点消失、叶片扭曲、黄化等表型性状