多取代烷基苯Kovats保留指数预测

提出一种从苯、单取代烷基苯及同取代基双取代烷基苯保留指数预测相关多取代烷基苯保留指数的简单、准确的新方法。只需做较少的实验,便可预测大量相关化合物的保留指数。研究表明,在４种固定相ＯＶ－１０１,Ｓｑｕａｌａｎｅ,ＳＥ－３０,ＰＥＧ－２０Ｍ上,计算出每一根柱子的保留指数Ⅰ的标准偏差在±２．４ｉ．ｕ．～±３．７ｉ．ｕ．之间。     

气相色谱分析二甲苯异构体的协同效应研究

在以全戊基β－环糊精和ＡｇＮＯ３全戊基β－环糊精和ＴＩＮＯ３以及机皂土－３４和ＡｇＮＯ３为混合固定相对间二甲苯及对二甲苯进行ＧＣ分离的过程中，发现前两种混合固定相具有协同效应，而后一种却是加和效应。     

界面张力对高分子共混物梯度相形态形成的影响研究

研究了界面张力对ＰＰ／ＥＶＡ共混体系梯度相形态形成的影响。首先将ＥＶＡｃ进行皂化反应得到一系列－ＯＨ基含量不同即极性不同的ＥＶＡ，然后将这些ＥＶＡ分别与ＰＰ共混从而得到一系列相界面张力不同的共混物。说明通过对共混物相界面张力的调整，可以达到随意控制梯度相形态形成速度的目的。     

A NOVEL REARRRANGEMENT OF as-TRIAZOLIUM SALT TO 5-AMINOIMI DAZOLE DERIVATIVE

Ａ　ＮＯＶＥＬ　ＲＥＡＲＲＲＡＮＧＥＭＥＮＴ　ＯＦ　ａｓ－ＴＲＩＡＺＯＬＩＵＭ　ＳＡＬＴ　ＴＯ　５－ＡＭＩＮＯＩＭＩ　ＤＡＺＯＬＥ　ＤＥＲＩＶＡＴＩＶＥＡＮＯＶＥＬＲＥＡＲＲＲＡＮＧＥＭＥＮＴＯＦａｓ－ＴＲＩＡＺＯＬＩＵＭＳＡＬＴＴＯ５－ＡＭＩＮＯＩ...     

含偶氮苯生色团的聚醚的合成与热致液晶性质

β－氯乙基缩水甘油醚（ＧＣＥ）和ＧＣＥ／羟丁基乙烯基醚（ＨＢＶＥ）分别通过阳离子聚合、光引发共聚合,获得两种聚醚,然后再分别与４－硝基－４’－羟基偶氦苯（ＮＨＡ）反应,制备了两种侧链含偶氦苯生色团的液晶聚合物（ＰＡＥＧ、ＰＡＶ）。用ＦＴＩＲ、＾１Ｈ－ＮＭＲ和ＥＡ对其化学结构及生色团含量进行了表征,以ＰＯＭ,ＤＳＣ、ＴＧＡ和ＷＡＸＤ对聚合物介晶相转变温度、织构、热稳定性及相行为进行了研究。结果表明,     

STUDIES ON THE MAGNETIC RESONANCE CONTRAST AGENTS SYNTHESIS AND SPIN－LATTICE RELAXIVITY OF AMINO ACIDS AND OLIGOPEPTIDYL DERIVATIVES OF GD－DTPA

ＳＴＵＤＩＥＳＯＮＴＨＥＭＡＧＮＥＴＩＣＲＥＳＯＮＡＮＣＥＣＯＮＴＲＡＳＴＡＧＥＮＴＳ：ＳＹＮＴＨＥＳＩＳＡＮＤＳＰＩＮ－ＬＡＴＴＩＣＥＲＥＬＡＸＩＶＩＴＹＯＦＡＭＩＮＯＡＣＩＤＳＡＮＤＯＬＩＧＯＰＥＰＴＩＤＹＬＤＥＲＩＶＡＴＩＶＥＳＯＦＧＤ－ＤＴＰ...     

A NOVEL SYNTHESIS OF 3-PHENYL-1H-INDAZOLE DERIVATIVES

ＡＮＯＶＥＬＳＹＮＴＨＥＳＩＳＯＦ３－ＰＨＥＮＹＬ－１Ｈ－ＩＮＤＡＺＯＬＥＤＥＲＩＶＡＴＩＶＥＳＺｈｅｎＱｉＺＨＯＮＧ；ＹｕＺｈｕＱＵＩ；ＺｈｅｎｇＺＨＡＮＧ，ａｎｄＨｏｎｇＷｅｎＨｕＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ．ｈａｎｊｉｎｇＵｎｉｖ...     

一种非晶硅膜改性弹性玻璃毛细管交联中等极性固定相色谱柱的制备

研究了非晶硅膜改性的弹性玻璃毛细管交联ＯＶ－１７０１中等极性固定相色谱柱。在适当温度下，采用过氧化二异丙苯（ＤＣＵＰ）游离基引发交联ＯＶ－１７０１固定液，成功地制备了交联ＯＶ－１７０１柱，该柱具有柱效高、惰性好、耐溶剂、抗腐蚀和耐高温等性能，是一种新型高性能的中等极性交联柱。     

HIGH－PERFORMANCE CAPILLARY ELECTROPHORESIS OF REDUCING OLIGOSACCHARIDES AS THEIR ETHYL P－AMINOBENZOATE DERIVATIVES

ＨＩＧＨ－ＰＥＲＦＯＲＭＡＮＣＥＣＡＰＩＬＬＡＲＹＥＬＥＣＴＲＯＰＨＯＲＥＳＩＳＯＦＲＥＤＵＣＩＮＧＯＬＩＧＯＳＡＣＣＨＡＲＩＤＥＳＡＳＴＨＥＩＲＥＴＨＹＬＰ－ＡＭＩＮＯＢＥＮＺＯＡＴＥＤＥＲＩＶＡＴＩＶＥＳ￥ＬｉＷｅｎＣＨＡＮＧ；ＱｉｎｇＧＵＯ；Ｚ...     

STUDIES ON GLYCOSIDES XⅢ．──HIGHLY STEREOSELECTIVE SYNTHESIS OF PER－O－BENZYLATED O－，S－α－D－GALACTOPYRANOSIDES AND GALACTOSYL CARBOXYUTES FROM PER－O－BENZYIATED GALACTOSYL TRIFLUOROACETATE

ＳＴＵＤＩＥＳ　ＯＮ　ＧＬＹＣＯＳＩＤＥＳ　ＸⅢ．──ＨＩＧＨＬＹ　ＳＴＥＲＥＯＳＥＬＥＣＴＩＶＥ　ＳＹＮＴＨＥＳＩＳ　ＯＦ　ＰＥＲ－Ｏ－ＢＥＮＺＹＬＡＴＥＤ　Ｏ－，Ｓ－α－Ｄ－ＧＡＬＡＣＴＯＰＹＲＡＮＯＳＩＤＥＳ　ＡＮＤ　ＧＡＬＡＣＴＯＳＹＬ　ＣＡ...     

2-Pyridinoformamide-derived thiosemicarbazones and their iron(III) complexes: Potential antineoplastic activity

The iron(III) complexes [Fe(2Am4DH)₂]Cl (1), [Fe(2Am4Me)₂]Cl (2) and [Fe(2Am4Et)₂]Cl (3) with 2-pyridineformamide thiosemicarbazone (H2Am4DH) and its N(4)-methyl (H2Am4Me) and N(4)-ethyl (H2Am4Et) derivatives were obtained and characterized by means microanalyses, infrared and EPR spectra. The electrochemical behavior of the complexes was investigated. The thiosemicarbazones and complexes (1) and (2) presented toxicity against Artemia salina at low concentrations. Since this bioassay has a good correlation with cytotoxic activity in human solid tumors, the studied compounds present potential pharmacological applications.     

Extraction of Am(III) from different acid media by di-2-ethyl hexyl phosphoric acid containing phosphorous pentoxide

The extraction of Am(III) from nitric, hydrochloric, oxalic, phosphoric and hydrofluoric acids was studied using 0.4F di-2-ethyl hexyl phosphoric acid (HDEHP) containing 0.1M phosphorous pentoxide (P₂O₅) in dodecane/xylene. The extraction with pure 0.4F HDEHP was found to be negligible from all the media studied. However, the presence of a small amount of P₂O₅ in it increased the extraction substantially. The distribution ratios of Am(III) obtained for HDEHP - P₂O₅ mixture 3M nitric acid containing different concentrations of oxalic acid/phosphoric acid/hydrofluoric acid are in the order of 200-250. The same for 3M hydrochloric acid is very high (800). These distribution ratios are sufficiently high for the quantitative extraction of Am(III) from all the acid media studied. Different reagents such as ammonium oxalate, sodium oxalate, oxalic acid, hydrofluoric acid, sodium carbonate and potassium sulphate were explored for the back extraction of Am(III) from 0.4F HDEHP + 0.1M P₂O₅ in dodecane/xylene. Of these, 0.35M ammonium oxalate and 1M sodium carbonate were found to be most suitable. The back extraction of Am(III) was also attempted with water and 1M H₂SO₄, HNO₃, HClO₄ and HCl solutions after allowing the extracted organics to degrade on its own. It was found that more than 90% of Am could be back extracted with these acids. Using this method more than 90% of Am(III) was recovered from nitric acid solutions containing calcium and fluoride ions.     

Oxidation and extraction of Am(VI) using a monoamidic extractant in 3D printed centrifugal contactors

A series of tests were performed using centrifugal contactors to evaluate the separation of Am(VI) from cerium, as well as to determine the efficiency of the contactors. All experiments were performed using 2-cm, acrylic 3D-printed centrifugal contactors. Solvent extraction tests were performed using 1 M N,N-di(2-ethylhexyl)butyramide (DEHBA)/dodecane and a nitric acid feed solution spiked with ²⁴³Am and ¹³⁹Ce and oxidized with 60 mg mL^?1 sodium bismuthate. Approximately 72% of the Am was extracted with a single contactor stage. Co-stripping of Am and Ce was demonstrated but attempts at selective stripping were not successful. Successful recycle of the used organic phase was demonstrated. Contactor efficiencies of 95–100% were obtained.     

Accurate purification age determination of individual uranium–plutonium mixed particles

Age of individual uranium–plutonium (U/Pu) mixed particles with various U/Pu atomic ratios (1–70) were determined by inductively coupled plasma mass spectrometry. Micron-sized particles were prepared from U and Pu certified reference materials. The Pu reference was stored for 4–6 years since the last purification (July 14, 2008). The Pu purification age was obtained from the ²⁴¹Am/²⁴¹Pu ratio which was calculated from the product of three measured ratios of Pu and Am isotopes in the eluted fractions. These ratios were measured by a high-resolution inductively coupled plasma mass spectrometer equipped with a desolvation system. Femto-gram to pico-gram quantities of Am, U, and Pu in a sample solution were sequentially separated on a small anion-exchange column. The ²⁴¹Am/²⁴¹Pu ratio was accurately determined by spiking pure ²⁴³Am into the sample solution. The average determined age for the particles for the five independent U/Pu ratios was in good agreement with the expected age with high accuracy (difference age 0.27 years) and high precision (standard deviation 0.44 years). The described analytical technique can serve as an effective tool for nuclear safeguards and environmental radiochemistry.

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Figure Young (4?6 y) Pu purification age of individual U/Pu mixed micron-sized reference particles for the five independent U/Pu ratios (1?70) were determined with 0.27±0.44 y difference from the expected age. Sub pico-gram quantities of Am, U and Pu were sequentially separated a small column, and their isotope ratios were accurately measured using an ICP-MS by applying the ²⁴³Am spiking technique to the analysis and correcting the impurity and the contaminations.

     

Evaluation of a rapid technique for measuring actinide oxidation states in a ground water simulant

A system using an ion chromatograph coupled to a flow-cell scintillation detector for rapidly measuring the oxidation states of actinides at low concentrations (<10–6M) in aqueous solutions was evaluated. The key components of the system are a cation–anion separation column (Dionex, CS5) and a flow cell detector with scintillating cerium activated glass beads. The typical procedure was to introduce a 0.5 ml aliquot of sample spiked with actinides in the +III to +VI oxidation states into a 5 ml sample loop followed by 4 ml of synthetic groundwater simulant. Separation was achieved at a flow rate of 1 ml/min using an isocratic elution with oxalic, diglycolic, and nitric acids followed by distilled water. Tests were first conducted to determine elution times and recoveries for an acidic solution (pH 2) and a ground water simulant (pH 8) containing Am(III), Pu(IV), Th(IV), Pu(V), and U(VI). Then, an analysis was performed using a mixture of Pu(IV), Pu(V), and Pu(VI) in the ground water simulant and compared to results using the DBM extraction technique. Approximate elution times were the same for both the acidic solution and the ground water simulant. These were as follows: Pu(V) at 10 min, Am(III) at 15 min, Pu(IV) at 25 min, Th (IV) at 28 min and U(VI) at 36 min. Recoveries for the acidic solution were quantitative for U(VI) and Th(IV) and exceeded 80% for Am(III). Recoveries for the ground water simulant were quantitative for U(VI), but they were generally not quantitative for Th(IV), Pu(IV), and Am(III). For Th(IV) and Pu(IV), less than quantitative recoveries were attributed to the formation of neutral hydroxides and colloids; for Am(III) they were attributed to insoluble carbonates and/or hydroxycarbonates. When applied to the measurement of plutonium in the ground water simulant, the technique provided showed good agreement with the dibenzoylmethane (DBM) extraction technique, but it could not distinguish between Pu(V) and Pu(VI). This was likely due to the reduction of Pu(VI) to Pu(V) in the sample by the oxalic acid eluent. However, in spite of this limitation, the technique can be used to distinguish between Pu(IV) and Pu(V) in aqueous environmental samples within a pH range of 4 to 8 and an E _H range of -0.2 to 0.6 V, the predominance region for Pu(III), (IV), and (V). In addition, this technique can be used to corroborate oxidation state analysis from the dibenzoylmethane (DBM) extraction method for environmental samples.     

In the pursuit for better actinide ligands: an efficient strategy for their discovery

A novel method for the efficient discovery of new types of minor actinide (MA) ligands is based on the unique combination of "tea bag" split pool combinatorial chemistry and screening based on the inherent radioactivity of the complexed cations. Four multicoordinating Am(3+) chelating groups, such as CMPO (diphenylcarbamoylmethyl)phosphine oxide), PICO (picolinamide), DGA (N,N'-dimethyldiglycoldiamide), and MPMA (N-methyl-N-phenylmalonamide), on a trityl platform immobilized on TentaGelS served as a model library for the development of the screening method. This model library was screened under various conditions (i.e., 0.001 M < or = [HNO3] < or = 3 M, NaNO3 < or = 4 M, and [Eu] < or = 10 x [ligand]) showing competitive extraction of the four ligands. Other libraries of 9 and 72 members were synthesized by functionalization of the trityl platform with ligating groups that are composed of four building blocks (including at least one amide and one (phosphoric) hydrazone moiety). The screening of these two libraries resulted in the discovery of two multicoordinate ligands that contain ligating groups previously not known to complex Am(3+). Both are N-isopropyl amides terminated with a p-methoxyphenyl hydrazide (A2B1C1D10 K(D(Am)) = 2197) or a p-nitrophenyl hydrazide (A2B1C1D11 K(D(Am)) =1989) moiety, respectively. They are more efficient than the immobilized tritylCMPO ligand (K(D(Am)) = 1280) at 3 M HNO3. This method has the advantages of a high analytical sensitivity and the direct comparison of the extraction results. The method also allows the competitive screening of multiple nuclides which can be quantified by their radioactive emission spectrum.     

Determination of neptunium in plutonium and mixed uranium-plutonium samples by isotope dilution gamma-spectrometry with243Am as a spike

A method was developed for isolating neptunium from Pu, U or mixed oxide (MOX) samples and its determination by isotope dilution -spectrometry (IDGS) using²³⁹Np (²⁴³Am) as a spike. Extraction chromatography with trilaurylamine fixed on a SGX-C18 support was used for the isolation of Np. The decontamination factors for U, Pu, Am and Pa vary between 1000–2000 and 100, respectively. The average separation yield of Np is (95±3)%. The amount of²⁴³Am required for spiking is about 0.2–0.3 g. It is recommended to use the pair of -rays 86.53 keV (²³⁷Np)-106.13 keV (²³⁹Np) for the assay of neptunium. A relative uncertainty of 4% or better is achievable in the analysis of plutonium samples, containing 0.4–80 g neptunium. The detection limit, under the proposed experimental conditions, is about 0.05 g Np. The results were compared with the results obtained by using high resolution -spectrometry (HRGS).     

Extraction of Am(III) by mixture of dihexyl N,N-diethylcarbamoylmethyl phosphonate and tributyl phosphate in benzene from nitric acid solutions

Extraction of Am(III) by dihexyl N,N-diethylcarbamoylmethyl phosphonate (CMP) in benzene from nitric acid solutions (pH 2.0 to 6.0M) has been studied. High extraction of Am(III) by CMP from 2–3M HNO₃ was observed. The species extracted was found to be Am(NO₃)₃·3CMP. The extraction was also done with mixtures of CMP+TBP and CMP+TOPO, where mixed species were extracted in the organic phase. The back-extraction experiments gave an efficient back-extraction of Am(III) by pH 2.0 (HNO₃) from the loaded CMP+TBP phase but a poor back-extraction from the loaded CMP+TOPO phase. The loading of Nd(III) by mixture of CMP and TBP was 50% of the CMP concentrations at a total Nd(III) concentration of 0.182M. The thermodynamic parameters of Am(III) extraction by a mixture of CMP and TBP were evaluated by temperature variation method, which suggests that the two-phase reaction is stabilized by enthalpy and opposed by entropy.     

Study in Aqueous Solutions of Bioactive 2-Pyridineformamide-Derived Thiosemicarbazones and Their Iron(II) and Iron(III) Complexes

The binary systems of iron(II) and iron(III) with 2-pyridineformamide thiosemicarbazone (H2Am4DH) and its N(4)-methyl (H2Am4Me), N(4)-ethyl (H2Am4Et) and N(4)-phenyl (H2Am4Ph) derivatives were studied in aqueous solution by pH-potentiometry, ultraviolet–visible spectroscopy and EPR spectra. The formation constants of the iron(II) and iron(III) complexes were calculated from potentiometric and electronic absorption data at 25 °C and ionic strength μ = 0.1 mol·L^?1 using the HYPERQUAD program. The values of the formation constant of the FeL species decrease in the order Fe:H2Am4DH > Fe:H2Am4Me ≈ Fe:H2Am4Et > Fe:H2Am4Ph in the same way as the basicity of the ligands. The species distribution diagrams show that the species FeL₂ predominates at physiological pH in the Fe:H2Am4DH, Fe:H2Am4Me and Fe:H2Am4Et systems. The similar EPR spectra of these iron(III) binary systems indicate the same coordination spheres around the metallic center and the EPR g values suggests that the unpaired electron is in the d_xy orbital, indicating a d _xz ² d _yz ² d _xy ¹ ground state configuration for the complexes. For the Fe(III):H2Am4Ph system the EPR results indicated dimerization and antiferromagnetic interaction due to the presence of only one thiosemicarbazone ligand around the metallic center.