1─（2─吡啶偶氮）─2─萘酚─6─磺酸衍生化反相高效液相色谱法测定铁、钴、镍

本文研究了水溶性试剂１－（２－吡啶偶氮）－２－萘酚－６－磺酸（ＰＡＮ－Ｓ）与铁（Ⅱ）、钴（Ⅱ）和镍（Ⅱ）之螯合物的衍生和液相色谱分离条件。在Ｎｏｖａ－ＰａｋＴＭＣ１８柱上，用含１０ｍｍｏｌ／Ｌ的ｐＨ５．０的醋酸－醋酸钠缓冲溶液的甲醇－水溶液（５０：５０，Ｖ／Ｖ）作流动相，溴化四丁基铵（ＴＢＡ·Ｂｒ）作离子对试剂，流动相流速为１．０ｍＬ／ｍｉｎ，在５５０ｎｍ波长处进行光度检测。在Ⅱｍｉｎ内用高效液相色谱分离测定了Ｆｅ（Ⅱ）、Ｃｏ（Ⅱ）和Ｎｉ（Ⅱ）与ＰＡＮ—Ｓ的螯合物，提出了离子对反相高效液相色谱快速分离测定痕量铁、钴、镍的新方法。信噪比（ＳＮＲ）为２时，检测下限分别为０．０４３、０．００７和０．０１２ｍｇ／Ｌ。     

1-(2-噻唑偶氮)-2-萘酚螯合物反相高效液相色谱法分离测定铜(Ⅱ)、铁(Ⅱ)和镍(Ⅱ)

以１－（２－噻唑偶氮）－２－萘酚（ＴＡＮ）作柱前显色剂，于ＯＤＳ柱上，用内含０．１ｍｏｌ／ＬＬｉＣｌ，５×１０－６ｍｏｌ／Ｌ ＴＡＮ和ＨＡｃ－ＮＨ４Ａｃ缓冲溶液（ｐＨ ５．５）的甲醇－水溶液（８０：２０，Ｖ／Ｖ）作流动相，流速为０．６ｍＬ／ｍｉｎ，并以紫外－可见检测器于５９０ｎｍ处进行检测，发展了一种ＲＰ－ＨＰＬＣ法同时分离测定铜（Ⅱ）、铁（Ⅱ）、镍（Ⅱ）的方法，方法灵敏度高，对于铜、铁、镍的检测限分别为１μｇ／Ｌ， ２ μｇ／Ｌ和 ０．４ μｇ／Ｌ。用于实际样品测定，结果满意。     

膜富集分光光度法测定微量锌

以５－Ｂｒ－ＰＡＤＡＰ为显色剂，用ＷＸ型混合纤维素滤膜（孔径０．６５μｍ，φ２５ｍｍ）富集微量锌，用乙醇溶解富集物（Ｚｎ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ）分光光度法测定锌，Ｚｎ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ在乙醇溶液中最大吸收波长为５５５ｎｍ，表观摩尔吸光系数１．０９×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，锌量在０．１～５．０μｇ／５ｍＬ，范围内符合比耳定律，本法灵敏度高，操作简便，应用于食品，水样中锌     

紫外分光光度-CPA矩阵法同时测定2-(2′-呋喃基)苯并咪唑和邻苯二胺

研究了２－（２′－呋喃基）苯并咪唑（ＦＢＤ）和邻苯二胺（ＯＰＡ）在无水乙醇溶液中的紫外吸收光谱，建立了多波长同时测定ＦＢＤ和ＯＰＡ的紫外光度ＣＰＡ矩阵法。ＦＢＤ和ＯＰＡ分别在０．１～１０ｍｇ／Ｌ和１．０～１００ｍｇ／Ｌ的浓度范围，ＦＢＤ和ＯＰＡ的回收率均大于９３％，相对标准偏差小于７．５％。     

5-Br-PADAB分光光度法测定钯

研究了４－（５－溴－２－吡啶偶氮）－１,３－二氨基苯（简称５－Ｂｒ－ＰＡＤＡＢ）分光光度法测定微量钯的反应,在乙酸介质中Ｐｄ（Ⅱ）与５－Ｂｒ－ＰＡＤＡＢ生成紫红色络合物,确定了分光光度法测定钯的新体系。在实验条件下试剂的最大吸收峰位于４３８ｎｍ处,络合物的最大吸收峰位于５６４ｎｍ处,表观摩尔吸光系数ε＝５．２０×１０－４Ｌ／ｍｏｌ．ｃｍ,用等摩尔连续变化法、摩尔比法测得络合比ｎ（Ｐｄ（Ⅱ））∶ｎ（５－Ｂｒ－ＰＡＤＡＢ）＝１∶１,钯离子的量浓度在４．２７×１０－８～１．５４×１０－５ｍｏｌ／Ｌ时,服从Ｂｅｅｒ定律。试验了３０种离子在一定量下不干扰测定。     

流动注射光度法同时测定铜基合金中的铝和铁

提出了同时测定铜基合金中铝和铁的流动注射分析法。以０．０４ｍｏｌ／ＬＨＣｌ作载液，铬天青Ｓ为显色剂，通过测定６２８ｎｍ处铝、铁两配合物的吸光度之和及铝配合物的吸光度，实现了两组分的同时测定。在优化的实验条件下，检测限：Ａｌ和Ｆｅ分别为１．６９×１０－３和１．７３×１０－３ｍｇ／Ｌ，Ａｌ浓度在０～０．８ｍｇ／Ｌ；Ｆｅ浓度在０～１．０ｍｇ／Ｌ时服从比耳定律。进样频率为６０样／ｈ，所拟方法用于实际样品分析，获得满意结果。     

一阶导数分光光度法同时测定镀层中的铁和镍

１引言在铁镍合金中添加适量的稀土元素能提高合金的机械性能，使其具有良好的抗蚀性和耐磨性。本文研究了以二甲酚橙为试剂和在适量表面活性剂ＣＴＭＡＢ存在下利用一阶导数分光光度法同时测定铁镍合金镀层中的铁和镍的最佳实验条件，并应用于含有微量稀土元素的铁镍合金镀层中铁和镍含量的同时测定，获得满意的结果。２仪器与试剂美国ＢｅｃｋｍａｎＤＵ－７ＨＳ型分光光度计；ＨＭ－２０Ｅ型ｐＨ计。５０ｍｇ／Ｌ铁标准溶液；５０ｍｇ／Ｌ镍标准溶液；ｐＨ为４．４的ＨＡｃ－ＮａＡｃ缓冲溶液（其中ＮａＡｃ的浓度为０．５ｍｏｌ／Ｌ）；…     

流动注射光度法测定铁的研究：Ⅱ.Fe（Ⅲ）—CAS—SAS胶束体系

用自行组装的ＦＩＡ装置，对Ｆｅ（Ⅲ）－ＣＡＳ－表面活性剂体系进行了系统研究。着重考察了表面活性剂的影响，选择了Ｆｅ（Ⅲ）－ＣＡＳ－ＴｒｉｔｏｎＸ－１００－ＨＤＭＡＡ混合胶束体系，拟定了Ｆｅ（Ⅲ）的ＦＩＡ光度法，用于总铁量的测定，方法的线性范围，检测限及采样速度分别为０～０．６ｍｇ．Ｌ＾－１，０．００２ｍｇ．Ｌ＾－１和９０样次ｈ＾－１，该法用于天然水或某些工业用水总铁量的测定，结果满意。     

水溶性新显色剂5-Br-PADN-S的制备与分析特性的研究及其用于锌的测定

报道了水溶性 １－（５－溴－２－吡啶偶氮）－２,７－萘二酚－６－磺酸（５－Ｂｒ－ＰＡＤＮ－Ｓ）的制备方法及其分析特性。研究了此试剂与锌（Ⅱ）等金属离子在水溶液中直接测定的显色反应,在ｐＨ １０．０～１１．４ 的Ｎａ２Ｂ４Ｏ７～ＮａＯＨ 缓冲溶液中,５－Ｂｒ－ＰＡＤＮ－Ｓ与锌（Ⅱ）形成２∶１ 的紫色配合物,最大吸收波长位于５４２ ｎｍ ,表观摩尔吸光系数ε５４２＝ ６．３８×１０４ Ｌ／（ｍ ｏｌ·ｃｍ ）,锌量在０～２０ ｍ ｇ／１０ Ｌ范围内符合比耳定律。在掩蔽剂的存在下,用于人发、奶粉及矿石等试样中锌的测定,结果与ＡＡＳ法一致。     

流动注射光度法测定铁的研究Ⅱ．Fe（Ⅲ）－CAS－SAS胶束体系

用自行组装的ＦＩＡ装置，对Ｆｅ（Ⅲ）－ＣＡＳ－表面活性剂体系进行了系统研究。着重考察了表面活性剂的影响。选择了Ｆｅ（Ⅲ）－ＣＡＳ－ＴｒｉｔｏｎＸ－１００－ＨＤＭＡＡ混合胶束体系，拟定了Ｆｅ（Ⅲ）的ＦＩＡ光度法，用于总铁量的测定。方法的线性范围、检测限及采样速度分别为０～０．６ｍｇ·Ｌ￣（－１）、０．００２ｍｇ·Ｌ￣（－１）和９０样次ｈ￣（－１）。该法用于天然水或某些工业用水中总铁量的测定，结果满意。     

Structural diversity in the self-assembly of Ag(I) complexes containing 2-amino-5-halopyrimidine

A series of Ag(I) complexes containing the 2-amino-5-halopyrimidine ligands have been synthesized and their structures characterized by X-ray crystallography. The isomorphous complexes Ag(L-Cl)₂(CF₃SO₃) (L-Cl = 2-amino-5-chloropyrimidine), 1, and Ag(L-Br)₂(CF₃SO₃) (L-Br = 2-amino-5-bromopyrimidine), 2, are mononuclear, while [Ag(L-Br)(CF₃SO₃)]₆·6C₄H₁₀O, 3, and [Ag(L-I)(CF₃SO₃)]₆ (L-I = 2-amino-5-iodopyrimidine), 4, show cyclic self-assembly of six Ag(Ι) atoms and six L-X ligands, resulting in 24-membered metallocycles. The complex [Ag(L-I)(CF₃SO₃)]_∞, 5, forms 1D zigzag chains which are linked through C-I?Ag and Ag?O interactions to form a 3D structure. The tetranuclear complexes [Ag(L-X)(NO₃)]₄ [X = Cl, 6; Br, 7] form 16-membered metallocycles, while [Ag(L-X)(ClO₄)]_∞ [X = Cl, 8; Br, 9] exhibit helical chains. The different structure of 5 from 1 and 2 appears to be due to the stronger nucleophilic character of the iodine atom. In these complexes, the relatively smaller NO₃⁻ anions lead to the formation of tetranuclear metallocycles and the larger CF₃SO₃⁻ anions support the hexanuclear metallocycles, whereas the ClO₄⁻ anions induce the helical chains.     

Ni-Nb2O5和Ni-Cu-Nb2O5催化甲烷燃烧活性研究

在微型固定床反应器中考察了新型甲烷催化燃烧催化剂Ni-Nb2O5和Ni-Cu-Nb2O5的活性．实验结果表明，含Nb2O5的Ni及Ni-Cu双金属催化剂具有好的催化甲烷低温燃烧性能，其甲烷转化率与反应温度、活性组分含量和空速有关．70％Ni担载量的Ni-Nb2O5催化剂可使甲烷在500℃时完全转化，并具有稳定的催化活性．Ni-Cu-Nb2O5体系催化剂中，Ni／Cu比为65／25时催化剂具有最佳的活性；该催化剂中Nb2O5可以在一个比较宽的范围内调节，并在此调节范围内可使甲烷在550℃温度下完全转化．     

An Improved Preparation of 2,5-Dimethoxy-tetrahydrofuran

ＡｎＩｍｐｒｏｖｅｄＰｒｅｐａｒａｔｉｏｎｏｆ２,５┐Ｄｉｍｅｔｈｏｘｙ┐ｔｅｔｒａｈｙｄｒｏｆｕｒａｎ＊Ｔｏｗｈｏｍｃｏｒｒｅｓｐｏｎｄｅｎｃｅｓｈｏｕｌｄｂｅａｄｄｒｅｓｅｄ．ＬＩＸｉａｏ－ｌｉａｎｄＣＨＥＮＱｉｎｇ－ｑｉ（Ｄｅｐａｒｔｍｅｎｔ...     

AEu2I5(A＝K,Rb,Cs)的合成及结构与性质研究

本文用一步反应合成了未见文献报道的化合物ＡＥｕ２Ｉ５（Ａ＝Ｋ，Ｒｂ，Ｃｓ），测定了这些化合物的组成、结构、熔点、密度、极谱电位、固体荧光光谱及在四氢呋喃中的紫外可见吸收光谱，解释了固体荧光光谱，确定了化合物中Ｅｕ的实际价态是＋２。     

Acyldesilylation of 5-Trimethylsilyl-2-furancarboxaldehyde

5－Acyl－2－furancarboxaldehydes2arelmpol－tantIntermedlateslforsynthesizingnaturallyoccuTTingfuranoldfattyacidswhichhaveantloxldanteffectsandantlneoplastlcactlvltlesInbiologicalsystems－．Nakayamaela尸reportedsuccessfulhalodesllylatlonofethyls－trlm...     

A convenient synthesis of 5-fluorofuran-2-carboxylic acid

A convenient synthesis of 5-fluorofuran-2-carboxylic acid has been achieved in two steps and 56% total yield. Fluorodenitration of commercially available benzyl 5-nitrofuran-2-carboxylate utilizing potassium fluoride and catalytic tetraphenylphosphonium bromide in sulfolane at 140 °C for 2 h furnished benzyl 5-fluorofuran-2-carboxylate. Hydrogenolysis of benzyl 5-fluorofuran-2-carboxylate gave the title compound.     

Facile Synthesis of Some New Pyrazole-Based 2-Thioxo-4-thiazolidinone

5-Ethoxymethylene-2-thioxo-4-thiazolidinone (1) reacts with hydrazine hydrate at room temperature to afford 5-(hydrazinylmethylene)-2-thioxo-4-thiazolidinone (3). Compound 3 condensed with different aromatic aldehydes 6a–d in ethanol in the presence of a few drops of piperidine to give the corresponding Schiff’s bases 7a–d. On the other hand, compound 3 reacts with o-hydroxybenzaldehyde derivatives 8a and 8b in refluxing ethanol catalyzed by a few drops of piperidine to yield 1H-inadzolyl-2-thioxo-4-thiazolidinones 9a and 9b. Reaction of compound 3 with α-ketoesters 10a and 10b or α-diketones 10c–e in refluxing glacial acetic acid furnished the pyrazolyl-2-thioxo-4-thiazolidinone derivatives 11a–e. Also, compound 3 reacts with some different enaminones 12a–f in refluxing glacial acetic acid to afford the new pyrazolyl-2-thioxo-4-thiazolidinone derivatives 13a–f. Pyrazoles 15a–d was obtained via reaction of compound 3 with chalcones 14a–d in dimethylformamide (DMF). The structures of all the newly synthesized products were confirmed on the basis of their elemental and spectral data, and a plausible mechanism has been postulated to account for their formation.     

Ca2B2O5的电子结构和能带结构

合成了标题化合物,在已测晶体结构的基础上,利用含组态作用的INDO/S方法计算了其他电子能带结构;利用态求和方法计算了微结构分子的线性极化率及其晶体的平均折射率。分析结果表明,价带主要由B^3^+和O^2^-离子的价轨道的贡献,导带底部主要由Ca^2^+离子轨道的贡献,从O^2^-离子到Ca^2^+离子的电荷转移对线性极化率起主要贡献。     

Acylation of Amines with 5-Phenyltetrazol-2-ylacetyl Chloride

The acylation of primary and secondary amines by 5-phenyltetrazol-2-ylacetyl chloride leads to the corresponding tetrazolylacetamides irrespective of the nature of the substituent in the structure of the amine.     

Reaction of 5,5-Dimethyl-2-oxotetrahydrofuran-4-ylacetohydrazide with Aldehydes and Ketones

The reaction of 5,5-dimethyl-2-oxotetrahydrofuran-4-ylacetohydrazide with a series of aldehydes and ketones led to the synthesis of systems which, according to the ¹H NMR spectra, exist exclusively in the linear form. According to the mass spectra, however, in the gas phase some of the compounds can also exist partly in the cyclic form. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 991–997, July, 2005.