多相氧载体CoO-MgO和氧分子作用的ESR研究

用ESK研究多相氧载体CoO-MgO表面上氧的吸附作用,发现在77-150K温度范围内表面Co²⁺离子和O₂的结合是可逆的,吸附产生Co³⁺-O₂^-自由基加合物有超精细结构的ESR谱;当温度增加,吸附态O₂^-自由基发生转移并稳定在Mg²⁺离子上形成Mg²⁺-O₂^-自由基,文中着重讨论Co³⁺-O₂^-自由基的电子结构和成键本质,认为自由基是通过自旋成对的方式形成的,由于σ-л键作用引起的自旋极化以及由于电子离域作用而引起的偶极作用与ESR制的超精细结构线产生有关。     

Self-Imaging Effect Based on Airy Beams with Quadratic Phase Modulation

The self-imaging effect based on Airy beams with quadratic phase modulation (QPM) in 1 + 1 and 2 + 1 dimensions is studied both numerically and analytically. It is demonstrated that, in spite of spatial spectral shape being kept invariant, both the intensity pattern and the accelerating trajectory of this self-imaging effect depend considerably on the QPM. When the QPM parameter is negative, the self-imaging accelerating wave exhibits deceleration and then acceleration, and the self-imaging scope can be expanded. In the opposite case, the self-imaging extent would be narrowed and the self-imaging accelerating wave will only accelerate during propagation. Numerical simulations agree with the theoretical results very well. This study shows the possibility of controlling the self-imaging effect based on 1D and circular Airy beams, by purposely choosing appropriate QPM parameters.     

Four New 1,4‐Benzoquinone Derivatives and One New Coumarin Isolated from Ardisia gigantifolia

Four new 1,4‐benzoquinone derivatives, belamcandaquinones J ( 1 ), K ( 2 ), L ( 3 ), and M ( 4 ), and one new coumarin, 5 , were isolated from the rhizome of Ardisia gigantifolia. Their structures were established by means of spectroscopic methods, and their cytotoxicity was tested in vitro against the cell lines PC‐3, EMT6, A549, Hela, RM‐1, and SGC7901. In comparison with cisplatin, compound 5 showed strong cytotoxicity with an IC₅₀ value of <30 μM against the cell lines PC‐3 and A549. Compounds 1 – 4 showed no cytotoxicity against all cell lines.     

Self‐Supporting Metal–Organic Layers as Single‐Site Solid Catalysts

Metal–organic layers (MOLs) represent an emerging class of tunable and functionalizable two‐dimensional materials. In this work, the scalable solvothermal synthesis of self‐supporting MOLs composed of [Hf₆O₄(OH)₄(HCO₂)₆] secondary building units (SBUs) and benzene‐1,3,5‐tribenzoate (BTB) bridging ligands is reported. The MOL structures were directly imaged by TEM and AFM, and doped with 4′‐(4‐benzoate)‐(2,2′,2′′‐terpyridine)‐5,5′′‐dicarboxylate (TPY) before being coordinated with iron centers to afford highly active and reusable single‐site solid catalysts for the hydrosilylation of terminal olefins. MOL‐based heterogeneous catalysts are free from the diffusional constraints placed on all known porous solid catalysts, including metal–organic frameworks. This work uncovers an entirely new strategy for designing single‐site solid catalysts and opens the door to a new class of two‐dimensional coordination materials with molecular functionalities.     

Structure elucidation and NMR assignments for two xanthone derivatives from a mangrove endophytic fungus (No. ZH19)

The structure elucidations and complete ¹H and ¹³C NMR assignments are reported for two new xanthone derivatives: 1,7‐dihydroxy‐2‐methoxy‐3‐(3‐methylbut‐2‐enyl)‐9H‐xanthen‐9‐one (1) and 1‐hydroxy‐4,7‐dimethoxy‐6‐(3‐oxobutyl)‐9H‐xanthen‐9‐one (2). Both of these secondary metabolites were isolated from the fermentation medium of a mangrove endophytic fungus (No. ZH19). High‐resolution electron impact mass spectrometry (HREIMS), Fourier transform infrared (FT‐IR) absorption spectrometry, and NMR experiments including gCOSY, gHMQC, and gHMBC were used for the determination of the structures and NMR spectral assignments. Preliminary pharmacological test showed that compounds (1) and (2) inhibited KB cells with IC₅₀ values of 20 and 35 µmol/ml, and KB_V200 cells with IC₅₀ values of 30 and 41 µmol/ml, respectively. Copyright © 2009 John Wiley & Sons, Ltd.     

β-DDB及其衍生物的结构与红外光谱特征

总结归属了肉豆寇醚酸甲酯、6－Br肉豆寇醚酸甲酯、β-DDB（6,6′－二甲氧基－4,5,4′,5′－二次甲二氧基－2,2′－二甲氧羰基联苯）及其5种衍生物的主要红外吸收谱带和特征,讨论了其红外吸收频率随化合物结构变化的规律。 结果表明分子中酯基的改变主要对羰基的伸缩振动频率有较大的影响,而对苯环的骨架振动影响较小;当苯环上H原子被其他取代基取代时,羟基及苯环的骨架吸收均发生显著变化。     

高效液相色谱法制备罗汉果甜甙Ⅴ标准品

为深入研究罗汉果中功能成分的药理药效,进一步开发罗汉果中的有效成分,将罗汉果鲜果的水提物以AB 8吸附树脂分离、D 280离子交换树脂脱色后,利用半制备高效液相色谱法得到三萜皂甙类化合物罗汉果甜甙Ⅴ标准品,纯度达98 5%。色谱柱为AlltechEconosphereNH2柱;流动相为乙腈 水(体积比为68∶32)溶液,流速5mL/min;检测波长203nm;柱温40℃。此方法具有操作简便、重现性好、产品纯度高等优点。     

Magnetic microparticle antibodies and their application to RIAs

Three types of magnetic microparticle antibodies were developed: 1) magnetic second antibody I (MSA-I) where the antibody molecules were directly immobilized by physical adsorption on Fe₃O₄ microparticles (magnetic nucleus, MN) 10nm±34% in diameter, 2) magnetic second antibody II (MSA-II) where the antibody molecules were immobilized by chemical coupling on the MN coated with polyacrolein, and 3) magnetic, first antibody (MFA-T₃) where the anti-T₃ antibody molecules were specifically immobilized by immunoadsorption to the second antibody molecules of the MSA-II. The optimal conditions for their preparation were elaborated. Some physical, chemical and immunological characteristics of these magnetic microparticles were described. The application of the MSA-I, MSA-II and MFA-T₃ to RIAs for evaluation of thyroid function, such as triiodothyronine (T₃), reverse T₃(rT₃), free T₃ (fT₃), thyroxine (T₄), free T₄(fT₄), thyroid-stimulating hormone (TSH), thyroglobulin (TG) and TG-antibody (TG-Ab), etc., was reported.It is a final report of Research Contract No. 6485/ RB and part of Coordinated Research Programme on Antibodies Immobilized on Magnetic Particles for Radioimmunoassay and Immunoradiometricassay of Hormones, supported by International Atomic Energy Agency.