大鼠脑组织中轻稀土元素含量相关性研究

研究了轻稀土元素La、Ce、Pr、Nd、Sm、Eu、Gd在大鼠脑组织中的吸收规律和蓄积特点.将雄性SD大鼠随机分为空白、对照、低、中、高及排毒组,每组10只,4周后处死,取脑组织.排毒组停止灌胃后继续饲养4周后处死取脑组织.用ICP-MS测定脑组织中上述稀土元素含量并做统计学分析.结果表明低、中、高剂量组大鼠脑组织中轻稀土元素含量逐渐增高,排毒组介于中、高剂量组之间;脑组织中轻稀土元素的含量远低于其他脏器;La、Ce、Pr在脑中分布符合奥多-哈尔金斯规则,Nd元素呈负偏离;多数轻稀土元素在脑和毛发中含量相关系数较高.稀土元素在脑组织中蓄积有量效关系,且蓄积具有可逆性;血-脑屏障对稀土元素的通透有一定阻碍作用;稀土元素在脑组织中的蓄积率不受摄入量的影响;毛发比全血更适合作为脑组织轻稀土元素含量的生物标志物.     

湖州表层土壤稀土元素含量及分布特征

为了研究湖州表层土壤样品中稀土元素的分布特征,利用ICP-MS测定了土壤中稀土元素的含量。结果表明湖州表层土壤中稀土元素含量的大小顺序为：Ce＞La＞Nd＞Pr＞Sm＞Gd＞Dy＞Yb＞Er＞Eu＞Ho＞Tb＞Tm＞Lu,遵循Oddo-Harkins法则。湖州表层土壤中稀土元素的分量均值和总量均值皆高于全国水平,稀土元素存在显著的分馏现象,轻稀土元素明显富集。表层土壤中Ce和Eu都有部分亏损。     

乳腺肿瘤患者血清稀土元素的检测与分析

比较乳腺肿瘤和对照人群血清稀土元素含量差异,探究恶性肿瘤患者不同分化类型与血清稀土元素含量的相关性,为乳腺肿瘤的治疗及预后提供科学依据;采用病例对照研究,纳入90例乳腺肿瘤患者(良恶性肿瘤患者各45例)和95例对照,恶性肿瘤患者进一步细化为高分化组28例和低分化组15例;利用电感耦合等离子体质谱仪(ICP-MS)测定两组人群血清中15种稀土元素的含量;结果显示La, Ce, Pr, Nd, Sm, Y, Eu, Gd, Tb, Dy, Ho, Er, Tm 13种稀土元素浓度在病例组和对照组间的差异有统计学意义(P0.05),其中La, Ce, Pr, Nd, Sm, Y含量在仪器定量限以上,且病例组中浓度均低于对照组浓度; Logistic回归显示La, Ce, Y调整人口学特征后OR值有统计学意义(P0.05);血清La, Ce, Pr, Nd, Sm, Y浓度在对照组、良性肿瘤组、恶性肿瘤高低分化组间差异有统计学意义(P0.05);相关分析显示Ce, Pr, Nd, Sm, Y与乳腺恶性肿瘤组织学评分存在一定的关联(P0.05),且均为负相关。结论:良性、恶性乳腺肿瘤均会导致病人血清稀土元素含量下降,元素La, Ce, Y可能是乳腺肿瘤患者的保护因素,乳腺恶性肿瘤恶化程度与体内稀土元素代谢紊乱存在一定关联。     

用单-2-乙基己基磷酸体系薄层层析法分离稀土元素的研究

在硅胶H/硝酸铵/CMC/H_2O(W/W33:1:1:100)的薄层板上以单-2-乙基己基磷酸/甲基异丁基酮/异丙醚/硝酸(V/V1:12:8:20)为展开剂时,各稀土元素间能同时表现出一定的△R:值。分离La、Ce、Pr、Nd、Sm、Gd、Dy、Er、Y、Yb的混合液,定性结果令人满意。经对寻乌、定南混合稀土矿分离、测试,确定了寻乌矿中含有稀土元素是La、Pr、Nd、Sm、Gd、Dy、Y;定南矿中含有稀土元素是La、Ce、Pr、Nd、Sm、Gd、Dy、Er、Y、Yb。     

薄层色谱法分离稀土元素——N_(263)正辛醇-石油醚-盐酸体系的研究

本文报告了薄层色谱法分离稀土元素的最佳条件。当选择N_(263)正辛醇-石油醚-浓盐酸展开剂的体积比为2.0:6.0:30.0:1.2时,可将La、Ce、Pr,Nd、Sm(或Eu、Gd)完全分离:当体积比为2.0:10.0:30.0:1.0时,Tb,Dy(或Ho),Er、Tm、Yb、Lu可获得满意分离;而体积比为2.0:7.0:30.0:1.0时,La、Ce、Pr、Nd、Sm(或Eu、Gd)、Tb(或Dy、Ho)、Er、Tm、Yb、Lu经一次展开可获得完全分离。用三溴偶氮胂作显色剂,检测下限可达0.01μg。     

电感耦合等离子体质谱分析莲子芯茶中的稀土元素

建立了一种压力密闭消解电感耦合等离子体质谱法测定莲子芯茶中Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu等15种稀土元素的方法。用该方法分析国家标准物质中的稀土元素,分析结果与标准值一致,并用该方法对莲子芯茶实际样品进行了分析。     

薄层色谱法分离稀土元素的研究

本文报道了用薄层色谱法分离轻稀土元素的色谱条件。在硅胶-淀粉-硝酸铵的薄层板上,研究了展开剂N263/正辛醇/石油醚/浓HNO_3各组份比例的变化对轻稀土元素R_f值的影响。实验结果表明,各稀土元素的R_f值随它们的原子序数增大而减小;当选择展开剂各组份的最佳体积比为6.0:7.0:25.0:1.0时,La、Ce、Pr、Nd、Sm、Eu和Gd七个稀土元素可获得完全分离,用三溴偶氮胂作显色剂,稀土元素的检测极限可达0.01μg。     

薄层色谱分离测定十五种稀土元素

本文论述了用薄层扫描分离测定稀土元素的新方法。当流动相为二-(2-乙基已基)磷酸酯(HEDHP)/单-(2-乙基己基)-2-乙基己基磷酸酯(HM(EH)EHP)/磷酸三丁酯(TBP)/四氢呋喃(THF)/硝酸(HNO_3)/异丙醚(i-Pr_2O)(111 52 5 521 86 10000 V/V)时,第一组元素(La,Ce,Pr,Nd,Sm)能完全分离;第二组元素(Eu,Gd,Tb,Dy,Y,Ho,Er,Tm,Yb,Lu)的Rf值均大于第一组元素,且不干扰测定。当流动相为HDEHP/HM(EH)EHP/TBP/THF/HNO_3/i-Pr_2O(68 43 27 460 103 10000 V/V),第二组元素能完全分离,此时第一组元素停留在起始线上,二组互不干扰。同时对稀土元素进行了定量测定的研究,在0.030～0.600(μg)的范围内,各稀土离子的测定符合比耳定律,测得各稀土元素的检出限La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Y,Ho,Er,Tm,Yb,Lu分别为14,15,18,17,15,14,14,17,18,14,21,23,29,30和31ng。样品中各稀土元素的回收率除样品1中La和Pr偏大一些外,均在95%～108%范围内。各样品中测得的稀土元素含量和光谱法所测得结果基本相符,结果令人满意。     

密云县潮河流域沿岸铁矿集中区土壤中稀土元素的地球化学特征及粒度效应

研究评价了原土及粒级土壤中稀土元素地球化学特征以及粒度效应。采用ICP-MS对原土和各个粒级土壤中15种稀土元素,包括La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu和Y进行了测定。结果表明:研究区内土壤中稀土元素的含量高于中国大陆土壤稀土元素背景值,平均值变化较大;15种稀土元素含量与不同粒级的关系趋势一致,即随着粒径的减小而呈现增大的趋势;原土及各粒级土壤经Masuda(1973)的6个Leedy球粒陨石平均值标准化后,REEs的配分模式一致,呈富集轻稀土的右倾型,明显的Eu负异常,Ce弱亏损,主要受陆源控制。潮河流域沿岸土壤中REE随粒度的变化特征与粘土矿物对其吸附及不同粒级中的矿物成分密切相关。该研究结论为选取稀土元素作为示踪剂提供了科学依据,并为不同粒径组分中稀土元素的进一步研究提供一定的参考价值。     

迭代目标转换因子分析法及其在光度分析中的应用——轻稀土元素多组份同时测定的研究

本文提出一种新的因子分析计算方法,即迭代目标转换因子分析法,避免了对转换矩阵求逆的运算过程,降低了实验误差在计算过程中放大的可能性,从而提高了浓度计算的准确度。用本文方法对La、Ce、Pr、Nd、Sm、Eu、Gd等稀土元素7组份混合物合成样品进行了分析,获得了满意的结果。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.