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1.
运用二元碱氮置换吸附红外光谱法、分子筛孔径分布测定技术、XPS技术,考察了丝光沸石表面酸性与孔结构的相互关系、钯在丝光沸石上分布情况和价态及其与沸石的相互作用。结果表明,随着丝光沸石脱铝程度的增加,表面出现大量不规整晶格,存在较多的次级孔道。强质子酸中心主要分布在它的“外表面”。钯在其表面富集,并与“外表面”上的质子酸中心协同作用,促进了轻质烷烃异构化反应。  相似文献   
2.
The colour reaction of 4-hydroxyiminomethyl-1-methylpyridinium chloride (PAM-4Cl) and palladium(II) chloride has been investigated. The optimum reaction conditions, spectral characteristics, conditional stability constant and composition of the yellow water-soluble complex have been established. A new spectrophotometric method is proposed for the microdetermination of PAM-4Cl.  相似文献   
3.
We report 11 patients seen between 1991 and 1994 with oral lichenoid lesion(OLL). In 10 cases, there was contact with dental amalgam fillings, and in patient no. 10 with both amalgam restorations and a gold crown. The last patient had, in addition to her OLL, lichen planus of the skin and genital mucosa. In 5 cases, combined sensitization to mercury and other metal salts, particularly gold sodium thiosulfate (GST) and palladium chloride (PDC), was observed. In 10 patients, the lesions considerably improved or totally cleared within 1 to 9 months of replacement of restoration materials. Histological examination of biopsies from the test sites of amalgam, mercuric chloride, GST and PDC, taken 10 or 17 days, after application of patch tests, showed lichenoid changes in 7 patients with at least 1 of the allergens. At least 2 patients had inflammatory lesions of the oral mucosa related to both amalgam and gold restorations, combined sensitization to inorganic and organic mercury derivatives. GST and, in 1 case, PDC, a "dental restoration metal intolerance syndrome" is proposed.  相似文献   
4.
The synthesis of a 11C‐labelled methyl stannane, (5‐[11C]methyl‐1‐aza‐5‐stanna‐bicyclo[3.3.3]undecane ( 2 )), and its use in palladium‐mediated Stille reactions to form [11C]C–C bonds are described. Stannane 2 was synthesized from iodo[11C]methane, 5‐chloro‐1‐aza‐5‐stanna‐bicyclo[3.3.3]undecane 1 and butyl lithium in 20–90% decay‐corrected radiochemical yield starting from iodo[11C]methane. Subsequent reaction with a series of substituted aryl and vinyl halides produced the corresponding [11C]methylated products 3–5 in up to 90% decay‐corrected radiochemical yield from the crude 2 . The total synthesis time, including purification, was 25–30 min from end of radionuclide production. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
5.
新显色剂5-APAQ分光光度法直接测定药品中的残留钯   总被引:2,自引:0,他引:2       下载免费PDF全文
 目的:建立一种药品中有害杂质钯残留量的测量技术。方法:采用新试剂5-(对-胂酸基苯偶氮)-8-氨基喹啉(5-APAQ)与钯发生络合反应显色,用分光光度法进行测量。结果:在pH10~14的水溶液中,显色络合物的最大吸收波长为653nm,摩尔吸收系数为1.05×105,吸光度与钯含量在0μg·ml-1~1.2μg·ml-1成线性关系。结论:实验证明,本方法特异性强、灵敏度高、操作简便快捷。  相似文献   
6.
The purpose of this study was to produce low-releasing spray-dried polymeric microparticles (MP) useful to target alveolar macrophages in tuberculosis (TB) inhalation therapy.  相似文献   
7.
目的 建立福沙吡坦中痕量钯的测定方法,并验证除钯工艺的效果。方法 采用微波消解法处理样品,石墨炉原子吸收分光光度法测定福沙吡坦中钯的残留量。结果 钯质量浓度在5~50μg/L范围内与吸光度线性关系良好(r=0.999 9),检出限为1.68μg/L,样品中的最低检出浓度为0.22μg/g;方法平均回收率为100.82%,RSD=3.34%(n=9)。结论 采用该方法测定福沙吡坦中钯的残留量,方法灵敏、准确、可靠,为药品的质量控制提供了依据。  相似文献   
8.
Novel Pd(II) complex with N‐heteroaromatic Schiff base ligand, derived from 8‐quinolinecarboxaldehyde (q8a) and ethyl hydrazinoacetate (haOEt), was synthesized and characterized by analytical and spectroscopy methods. The structure of novel complex, as well as structures of its quinoline and pyridine analogues, was optimized by density functional theory calculations, and theoretical data show good agreement with experimental results. A cytotoxic action of the complexes was evaluated on cultures of human promyelocytic leukemia (HL‐60), human glioma (U251), rat glioma (C6), and mouse fibrosarcoma (L929) cell lines. Among investigated compounds, only complexes with quinoline‐based ligands reduce the cell numbers in a dose‐dependent manner in investigated cell lines. The observed cytotoxic effect of two isomeric quinoline‐based complexes is predominantly mediated through the induction of apoptotic cell death in HL‐60 cell line. The cytotoxicity of most efficient novel Pd(II) complex is comparable to the activity of cisplatin, in all cell lines investigated.  相似文献   
9.
N‐(2,5‐Dimethoxybenzyl)‐N‐(5‐fluoro‐2‐phenoxyphenyl)acetamide (DAA1106), a potent and selective ligand for peripheral benzodiazepine receptor, and eight structurally related analogues were labelled with 11C at the carbonyl position using a low concentration of [11C]carbon monoxide and the micro‐autoclave technique. A combinatorial approach was applied to synthesize the analogues using similar reaction conditions. Palladium‐mediated carbonylation using tetrakis(triphenylphosphine)palladium, various amines and methyl iodide or iodobenzene was employed in the synthesis. The 11C‐labelled products were obtained with 10–55% decay‐corrected radiochemical yields and the final product was more than 97% pure in all cases. Specific radioactivity was determined for the compound [carbonyl11C]DAA1106 using a single experiment and a 10‐µA h bombardment. The specific radioactivity, measured 36 min after end of bombardment, was 455 GBq/µmol. Synthetic routes to the precursors and reference compounds were also developed. The presented approach is a novel method for the synthesis of [carbonyl11C]DAA1106 and its analogues, and allows the formation of a library of 11C‐labelled DAA1106 analogues which can be used to optimize the performance as a potential positron emission tomography tracer. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
10.
采用石墨炉原子吸收光谱法测定泛昔洛韦中痕量钯。用1%盐酸处理样品,氘灯背景校正。3种不同浓度的加样回收率分别为101.3%、105.3%、109.5%,RSD分别为4.3%、0.8%、1.5%。  相似文献   
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