离子交换与微滤膜技术在过氧化氢净化中的应用

采用离子交换树脂吸附工业过氧化氢产品中的有机物及金属离子，再经微滤系统除去过氧化氢产品中不挥发物及细碎树脂颗粒，从而提高过氧化氢产品质量，以满足其在高级丝织物漂白，高级洗涤剂合成，某些化工合成，食品，医药及电子行业的需要。     

铬-二苯卡巴肼体系间接光度法测定过氧化氢

酸性条件下,Cr(Ⅵ)与二苯卡巴肼形成稳定的紫红色铬合物,在544nm处有最大吸收,利用过氧化氢对该体系的褪色作用可实现过氧化氢的间接测定,摩尔吸光系数为2.51×10     

DIRECT OXIDATIVE DEPROTECTION USING MONTMORILLONITE SUPPORTED AMMONIUM CHLOROCHROMATE UNDER CONVENTIONAL HEATING AND MICROWAVE IRRADIATION IN SOLVENTLESS SYSTEM

Abstract

Trimethylsilyl ethers are selectively and rapidly oxidized to the corresponding carbonyl compounds by montmorillonite k-10 supported ammonium chlorochromate under conventional heating and microwave irradition in solvent free condition.     

INACTIVATION OF PHAGE BY NEAR-ULTRAVIOLET RADIATION AND HYDROGEN PEROXIDE

A series of phage with different genomes (both single-stranded and double-stranded RNA and DNA) was inactivated with hydrogen peroxide (H₂O₂) in various combinations with far-ultraviolet (FUV) and near-ultraviolet (NUV) radiations. In every case but one (a lipid-coated phage), a sublethal H₂O₂ concentration greatly enhanced killing by NUV but not FUV. Moreover, this NUV/H₂O₂ synergism was oxygen independent and there was little if any host cell reactivation upon NUV plus H₂O₂ inactivation. These results suggest that these phage are inactivated by a common mechanism irrespective of nucleic acid composition, but that some phage genomes may be more vulnerable to NUV/H₂O₂ inactivation than others.     

OXIDATIVE COUPLING OF THIOLS BY PYRIDINIUM CHLOROCHROMATE IN SOLUTION AND SOLVENT FREE CONDITIONS

Oxidative coupling of aromatic and aliphatic thiols is achieved efficiently by pyridinium chlorochromate in solution and solvent free conditions. Omitting the solvent does not change the reaction time and product yield significantly, while the need of using the solvent is suppressed and workup procedure becomes easier.     

DNA-DENATURING EFFECT OF IRRADIATED HYDROGEN PEROXIDE

Abstract By an acridine dye method for analyzing DNA conformation, it was shown that hydrogen peroxide, in conjunction with irradiation at wavelengths longer than 290 nm, exerted a denaturing effect on linear duplex DNA. The effect was dose–related to a disappearing limit of 10 μM hydrogen peroxide.     

PHOTOINDUCED GENERATION OF HYDROGEN PEROXIDE AND HYDROXYL RADICALS IN MELANINS

The hydrogen peroxide produced during photolysis of melanin pigments has been measured using an oxidase electrode. The photooxidation has been shown to occur via the superoxide intermediate. In the presence of superoxide dismutase the rate of photo-induced production of hydrogen peroxide is increased, reflecting the ability of melanin to scavenge superoxide radicals. Evidence for metal-ion dependent formation of hydroxyl radicals during photooxidation of melanin pigments was obtained using electron spin resonance-spin trapping procedures. Superoxide dismutase increased the rate of formation of hydroxyl radicals in the system. Mechanisms of metal ion-induced production of hydroxyl radicals during photolysis of melanin pigments are discussed.     

DIRECT OXIDATIVE DEPROTECTION OF TETRAHYDROPYRANYL ETHERS USING HEXAMETHYLENETETRAMINE-BROMINE SUPPORTED ONTO SILICA GEL UNDER MICROWAVE IRRADIATION IN SOLVENTLESS SYSTEM

Primary and secondary tetrahydropyranyl ethers (THP ethers) are converted to their corresponding carbonyl compounds efficiently using hexamethylene-tetramine-bromine supported onto silica gel under microwave irradiation in solvent-free conditions.     

用微量热法研究漆酶和过氧化氢的反应

漆树酶是含铜酶。在酶系统中属于一种选择性较差的氧化酶,它能与许多还原底物作用,同时亦能还原分子氧生成水。在这些反应中漆酶中的三个不同的氧化还原活性中心和其作用途径常常是研究中的主要对象。在无氧条件下,漆酶被底物还原后,可用氧再氧化,实验表明,酶分子中的Cu2~+—Cu~(1+)循环是催化机理的一部分。1970年Farver等人在研究漆树酶与过氧化氢之间的反应时发现,漆树酶与过氧化氢有一种特殊作用,二者会生成一种稳定的具有高亲合力的复合物,该复合物不会被氧再氧化,其反应可用下式表示:式中L-Cu(Ⅱ)表示含二价铜的漆酶分子,二价铜在此反应中起活性中心的作用。本工作中,用微量热法测量了漆树酶与过氧化氢反应的一些热动力学性质。     

THE REACTION BETWEEN SUPEROXIDE ANION AND HYDROGEN PEROXIDE

Abstract— In order to obtain a better understanding of the kinetics of the Haber-Weiss reaction

often proposed as a source of OH radicals, we have measured the decomposition rate of H₂O₂ in aqueous solutions by y rays and for different pH values. This decomposition proceeds by a chain reaction involving the preceding one as the propagating step.
The rate constant found is to be
     

过氧化氢的热分解及其引发丙烯腈聚合反应的研究

本文研究了过氧化氢在二甲基甲酰胺中的热分解反应,测定了不同温度下的分解速率常数和表现活化能。同时研究了过氧化氢引发丙烯腈的聚合反应,确定了聚合动力学方程。     

过氧化氢中微量氯离子、硝酸根、磷酸根、硫酸根的同时测定

在碱性条件下,过氧化氢加热回流分解,经阳离子树脂交换后,离子色谱法分析。以Na2CO3 NaHCO3 为淋洗液,分析柱为 IonPac AS14,抑制电导同时测定过氧化氢中微量 Cl-、NO-3 、PO3-4 、SO2-4 。消除了过氧化氢对分析柱的可能损害,使基线更加平滑,具有测试简便,分析周期短,准确性高的特点,检出限为0.01~0.03 mg·L-1,应用于过氧化氢中无机阴离子的测定。     

A NEW APPLICATION OF N-BROMOSACCHARIN AS A SELECTIVE AND EFFICIENT OXIDATIVE REAGENT FOR REGENERATION OF CARBONYL COMPOUNDS FROM OXIMES

A new method for the direct conversion of various oximes into aldehydes and ketones by treatment with N-bromosaccharin is described. N-bromosaccharin can be used for an effective, selective and mild oxidizing agent for the regeneration of carbonyl compounds from oximes in good yield.     

Dawson结构钨钒磷杂多化合物催化苯酚过氧化氢的羟化作用及其羟化机理

合成了系列Ｄａｗｓｏｎ结构钨钒磷杂多化合物（Ｃｐｙｒ）７＋ｎＰ２Ｗ１８－ｎＶｎＯ６２（ｎ＝１～３），并用ＩＲ，ＮＭＲ等手段对其结构进行了表征．考察了这类杂多化合物对苯酚过氧化氢的羟化活性，探讨了反应机理．     

FLAVIN-MEDIATED PRODUCTION OF HYDROGEN PEROXIDE IN PHOTOELECTROCHEMICAL CELLS

A photoelectrochemical cell for hydrogen peroxide production using flavin photosystems is described. The anodic solution, which is kept free of oxygen by passing an Ar stream through it, contains the photoreceptor (flavin mononucleotide or lumiflavin) and the electron donor (EDTA, semicarbazide or hydroxylamine), while the peroxide is formed at the electrode of the cathodic solution, whose oxygen content is increased by bubbling with pure oxygen. Among several electrode metals that have been tested (Ag, Pt and Hg), Hg is the most efficient. The pH of the anodic and cathodic solutions should be adjusted to 14 and 1, respectively, for optimum results.     

FURTHER STUDIES ON THE KINETICS AND MECHANISM OF THE COPPER-IMIDAZOLE CATALYSED DECOMPOSITION OF HYDROGEN PEROXIDE

Abstract

The catalytic decomposition of hydrogen peroxide in the presence of the tetrakis(imidazole)copper(II) complex was investigated. The kinetics, based on the rates of oxygen evolution, indicated that a ternary copper(I1)-imidazole-peroxo complex is involved in the rate-determining step. The equilibrium constant for the coordination of hydrogen peroxide to the cupric ion, and the acid dissociation constant for the coordinated H202 ligand were calculated as 1.7 M¹ and 2.1 × 10⁹ M, respectively. The ternary complex undergoes intramolecular electron transfer, with k = 4 s¹, generating Cu(1) species which can react with hydrogen peroxide or dioxygen, returning to the catalytic cycle. A complete mechanism is proposed, based on the kinetics of oxygen and on the electrocatalytic behdviour observed for the copperimidazole complexes under a dioxygen atmosphere.     

BIOLOGICAL EFFECTS OF NEAR-UV RADIATION 2'-ACETYLFORMANILIDE-SENSITIZED FORMATION OF HYDROGEN PEROXIDE FROM NUCLEOSIDES AND NUCLEOTIDES

Abstraet—2'-Acetylformanilide has been found to be an effective, near-ultraviolet (300–380 nm) sensitizer for the photooxidation of nucleosides and nucleotides in aqueous solution, with hydrogen peroxide being formed in high yield. The decreasing order of hydrogen peroxide formation and substrate destruction was found to be: guanosine. adenosine, thymidine, uridine and cytidine. The process was highly pH dependent, low pH being most favorable for photooxidation. Experiments using deuterium oxide and superoxide dismutase indicate that both singlet oxygen and superoxide ion can be involved in hydrogen peroxide formation.     

碘量滴定法测定过氧化氢溶液浓度的改进

研究了用碘量滴定法测定过氧化氢浓度时，试剂的加入顺序和放置时间对测定结果的影响。结果表明，在用碘量滴定法测定过氧化氢浓度的过程中，酸化条件下，I^-与H2O2反应的最佳时间为5～10min。与高锰酸钾氧化法相比，碘量法测定效果较好一些。     

ACTION OF HYDROGEN PEROXIDE ON HUMAN FIBROBLAST IN CULTURE

Abstract— Human fibroblasts in culture lose the capacity of proliferating when exposed to hydrogen peroxide in the concentration range of 1 to 10 μ M . The toxicity of H₂O₂ to xeroderma pigmentosum cells (XP12RO). defective in excision repair of lesions produced by UV-irradiation, was about twice as high as to cells proficient in excision repair (VA13). This compound produces single-strand breaks in intracellular DNA but not in purified DNA. These breaks are in situ physical discontinuities rather than alkali-labile bonds, and their generation occurs at the same extent at 4°C and 37° indicating that they are not produced by an endonuclease. The results favor the hypothesis that H₂O₂ reacts in the cell producing a radical species which brings about the formation of DNA single-strand breaks. These breaks are effectively repaired by both XP12RO and VA13 fibroblasts. The possible reason for the lethality of H₂O₂ is discussed.     

EFFECT OF ZINC ON THE INTERACTION OF COPPER AND A SIMPLE PEPTIDE MOLECULE WITH HYDROGEN PEROXIDE

Abstract

Reaction of copper and of copper in presence of zinc with glycylglycine H₂Gg, H₂NCH₂CONHCH₂COOH (in ratios 1:2 and 1:1:2, respectively), and an excess of hydrogen peroxide results in the formation of a novel peroxy complex [Cu(O₂ ^2-) (H₂Gg)₂].2H₂O and a mixed metal peroxo carbonate complex [Cu, Zn(O₂ ^2-(CO₃)(H₂O)₄], respectively. A notable feature of the reaction is the facile decomposition of the peptide bond at room temperature on addition of zinc to the system.