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1.
张卫民  曾和平 《化学学报》2008,66(4):465-470
设计合成了2-[(2'-芴基)-乙烯基]-8-羟基喹啉(6)、2-[(2'-菲基)-乙烯基]-8-羟基喹啉(7)及其金属锌配合物89; 用UV-Vis, FT-IR, ESI-MS, 1H NMR和元素分析确认了化合物67的结构; 并用四甲基偶氮唑盐微量酶反应比色法(MTT法)研究了其调控骨髓间质干细胞增殖的作用, 结果表明, 化合物67对干细胞有明显的增殖作用. 用FT-IR, FAB-MS和元素分析表征了金属锌配合物结构, 光致发光光谱测试结果表明, 化合物8的发光峰值为602 nm, 发黄光; 化合物9的发光峰值为628 nm, 发橙红色光.  相似文献   

2.
合成了一类新型四酰胺杯[4]氮杂冠醚(5a, 5b), 用紫外和荧光光谱研究了主体与阴离子客体之间的识别性能. 主体分子5a5b加入到对硝基酚氧阴离子的CHCl3溶液中, 主客体间形成超分子复合物使得客体阴离子423 nm处吸光度降低且溶液从黄色变为无色. 受体5a, 5bp-NO2C6H4O, F, 相互作用, 荧光光谱发生变化, 并且对于p-NO2C6H4O具有较好的选择性识别能力, 其荧光光谱强度改变强弱的顺序为p-NO2C6H4O>F>H2PO4>>Cl, Br, I. 荧光光谱滴定的结果经非线性拟合, 结果表明主客体间形成1∶1络合物.  相似文献   

3.
系列Mn(II)配位超分子的合成、晶体结构和表面光电压研究   总被引:6,自引:0,他引:6  
张丽  牛淑云  金晶  孙丽萍  杨光第  叶玲 《化学学报》2007,65(11):1032-1038
采用水热合成方法得到了三种Mn(II)配位超分子: Mn(2,5-dcp)2(H2O)2 (1), Mn(INA)2(H2O)4 (2)和Mn(phen)2Cl2 (3) (2,5-dcp=pyridine-2,5-dicarboxylic acid, INA=iso-nicotinic acid, phen=1,10-phenanthroline). 通过X射线单晶衍射、红外光谱(IR)、紫外光谱(UV-Vis)及表面光电压光谱(SPS)等方法对化合物进行了表征. 三种化合物中均存在大量的氢键, 使化合物晶体构成了无限延伸的三维网络结构. 表面光电压谱显示了化合物13在300~600 nm范围内呈现出正的光伏响应带, 具有P-型半导体的特征. 讨论了氢键在超分子构建中的作用以及不同配位环境对于配合物表面光电压的影响.  相似文献   

4.
张强 《化学学报》2008,66(5):567-570
通过1,10-二氧-4,7,13,16-四氮杂18-冠-6 (1)与2-羟基-5-硝基苄基溴反应合成了一个四硝基酚取代的氮杂18-冠-6衍生物(2). 采用UV-Vis光谱法研究了混合溶剂中冠醚2对H, Mg2+, Ca2+, Sr2+, Ba2+和Pb2+的光谱响应及配位性能. 结果表明, 随溶液pH值的增大, 冠醚2的最大吸收峰由319 nm逐渐红移到426 nm, 并伴随着强度的增大; 其与几种阳离子形成配合物的稳定常数随阳离子半径的增加而增大, 从而展示了对Ba2+和Pb2+高的配位能力.  相似文献   

5.
C60与亚氨基二乙酸甲酯[NH(CH2COOMe)2]的光化学反应制得2,5-双(甲氧羰基)富勒烯吡咯烷(1), 产率为52% (基于已反应的C60). C60吡咯烷衍生物1与氯乙酸甲酯(ClCH2COOCH3)的N-烃基化反应, 在微波辐射、无溶剂及相转移条件下, 得到2,5-双(甲氧羰基)-N-(甲氧羰基)甲基富勒烯吡咯烷(2), 产率47%(基于C60吡咯烷衍生物1). C60吡咯烷衍生物12用NaH, CH3OH水解后, 经盐酸酸化得相应的二羧酸衍生物3和三羧酸衍生物4, 产率分别为65%和53% (基于C60吡咯烷衍生物12). C60吡咯烷衍生物14的结构由1H NMR, 13C NMR, IR, FAB-MS和元素分析证实. 用电导法测定了C60吡咯烷二羧酸3和三羧酸4钠盐的临界聚集浓度(CAC), 分别为3.58×10-4 mol/L (3)和3.33×10-4 mol/L (4). 这一结果被C60吡咯烷衍生物34, 在临界聚集浓度(CAC)附近的UV-Vis光谱的特征变化所支持. 透射电子显微镜(TEM)和静态光散射(SLS)等方法也被用于检测C60吡咯烷衍生物34在临界聚集浓度(CAC)时的聚集行为, 结果显示, C60吡咯烷衍生物3在缓冲溶液中(0.001 mol/L NaCO3-NaHCO3), 其聚集体粒径的大小(Rg≈21 nm)不同于C60吡咯烷衍生物4 (Rg≈23 nm). C60吡咯烷二羧酸3钠盐的临界聚集浓度(CAC)比C60吡咯烷三羧酸4钠盐的临界聚集浓度(CAC)大, 聚集体粒径大小的不同, 表明C60单加成衍生物加成基团中羧基(COOH)数目的多少对其聚集行为的影响. 用化学发光法分别检测了C60吡咯烷二羧酸3和C60吡咯烷三羧酸4在缓冲溶液(0.05 mol/L NaCO3-NaHCO3)中对邻苯三酚自氧化产生的超氧阴离子(O2·)的清除活性. C60衍生物34对 O2· 的清除呈现有明显的剂量效应, 但当超过一定浓度时(3: ~3.50×10-4 mol/L, 4: ~3.25×10-4 mol/L), 清除效率出现转折, 并下降. 这一现象与电导率测定时出现的CAC现象相一致, 进一步证实了C60吡咯烷二羧酸3和C60吡咯烷三羧酸4在较高浓度的水溶液中有聚集的倾向, 也说明了C60吡咯烷二羧酸3和C60吡咯烷三羧酸4的聚集会影响其清除超氧阴离子(O2·)的活性.  相似文献   

6.
合成了以三联吡啶锇Os(Ⅱ)配合物为光敏剂的PS-Fe2S2型模拟铁氢化酶分子光催化剂1a及其分子间光催化模型化合物1b2, 研究了配合物1a1b的吸收光谱, 发光光谱及电化学性质. 配合物1a1b均表现出三联吡啶锇Os(Ⅱ)配合物的MLCT吸收峰; 与不含Fe2S2基团的配合物1b相比, 在配合物1a中三联吡啶锇Os(Ⅱ)配合物单元的发光被明显猝灭, 猝灭程度为92%. 而在同样浓度下, 配合物1b2组成的分子间体系中三联吡啶锇Os(Ⅱ)配合物的发光仅被猝灭了4%. 通过Rehm-Weller方程计算得出由三联吡啶锇Os(Ⅱ)配合物单元到Fe2S2活性中心的光致电子转移自由能为正, 表明分子内1a和分子间1b+2体系均不能发生光致电子转移, 体系发光猝灭的原因是三联吡啶锇Os(Ⅱ)配合物3MLCT激发态与铁氢化酶模拟活性中心Fe2S2的能量转移.  相似文献   

7.
含氨基酸单元的手性主体的合成及手性识别研究   总被引:1,自引:0,他引:1  
L-丙氨酸和2,7-二萘酚为原料通过简单的方法合成了二种带有荧光基团萘的手性阴离子主体(12), 用红外光谱、质谱、元素分析、核磁共振氢谱及碳谱表征了它们的结构. 用荧光光谱及核磁共振氢谱研究了主体与二苯甲酰酒石酸阴离子的相互作用, 结果表明1, 2D-或L-二苯甲酰酒石酸阴离子均形成1∶1的配合物, 主体1展现出良好的对二苯甲酰酒石酸阴离子对映选择性识别能力.  相似文献   

8.
两种取代二茂铁基三甲基硅烷基氰醇醚的合成及晶体结构   总被引:1,自引:0,他引:1  
王晓丽  王艳学  边占喜 《化学学报》2007,65(16):1670-1674
通过两种取代的乙酰基二茂铁与三甲基氰硅烷的加成反应, 得到两种取代二茂铁基三甲基硅烷基氰醇醚的晶体: 1-(1-氰基-1-三甲基硅烷氧基乙烷基)二茂铁(1), 1,1'-二(1-氰基-1-三甲基硅烷氧基乙烷基)二茂铁(2), 用X射线单晶衍射、元素分析、红外光谱和核磁共振氢谱对分子结构进行了表征. 测试结果表明: 晶体1属正交晶系, Pbca空间群, a=1.1995 nm, b=1.2441 nm, c=2.2183 nm, Z=8, R1=0.0456, wR2=0.0880; 晶体2属正交晶系, Pna2(1)空间群, a=2.0715 nm, b=0.6440 nm, c=1.8411 nm, Z=4, R1=0.0485, wR2=0.0866. 晶体结构表明, 分子中都存在超共轭效应.  相似文献   

9.
李文玲  何侃侃  李瀛  侯自杰 《化学学报》2005,63(17):1607-1612
对四种天然二聚二苯乙烯类化合物Shegansu B (1), Gnetuhainin F (1a), Maackin A (2)以及Cassigarol E (3)的全合成进行了研究. 以3,5-二羟基苯甲酸(4)为起始原料, 经六步反应制得异丹叶大黄素(13)和白皮杉醇(14), 在HRP/H2O2酶催化氧化体系中, 1314分别进行自身的氧化偶联得到各自的二聚产物. 首次完成了1a, (±)-2和(±)-3的全合成, 并以较文献报道为高的氧化偶联产率合成了(±)-1.  相似文献   

10.
秦海娟  杨洗  何永炳  卿光焱  刘成金 《化学学报》2006,64(22):2271-2274
合成了一种带有荧光基团蒽的酰胺型双冠醚阴离子受体3. 用荧光光谱、紫外-可见吸收光谱及核磁共振氢谱研究了其与F, Cl, Br, I, H2PO4, AcO离子的相互作用, 结果表明3只对F具有很好的选择性识别能力, 并形成配合比为1∶2的络合物, 通过荧光发射强度计算出主体3与F间的相互作用时的结合常数.  相似文献   

11.
Irradiation of α-iodo ketone in hexane under a nitrogen atmosphere with a high-pressure mercury lamp (λ>300nm) at room temperature afforded the corresponding α,β-unsaturated ketones in good yield. This reaction affords a new, clean and convenient synthetic method for the α,β-unsaturated ketone.  相似文献   

12.
Photolysis of 2-phenylheptamethyltrisilane (I) in the presence of acyclic and cyclic conjugated dienes has been investigated using both a high-pressure mercury lamp with a quartz filter and a low-pressure mercury lamp with a Vycor filter. Irradiation of I in the presence of 1,3-butadiene, isoprene or 2,3-dimethylbutadiene with a high-pressure mercury lamp gave a product arising from photochemical isomerization of a silacyclopropane derivative and a compound apparently formed by 1,4-silylene addition, along with a 1/1 “ene” adduct of the diene to a photo-rearranged intermediate containing the silicon—carbon double bond. Irradiation of I in the presence of the conjugated diene with a low-pressure mercury lamp, followed by treatment of the product with methanol, afforded a methoxysilane arising from methanolysis of the corresponding silacyclopropane, together with the isomerization product, silacyclopentene and rearranged addition product. Irradiation of I in the presence of cyclopentadiene with a high-pressure mercury lamp produced methylphenylsilylcyclopentadiene, while irradiation of a similar mixture with a low-pressure mercury lamp followed by treatment with methanol gave 4-(methoxymethylphenylsilyl)-1-cyclopentene. With 1,3-cyclooctadiene, the photochemically generated methylphenylsilylene afforded many types of addition product. Photolysis of I in the presence of 1,3-cyclohexadiene, however, afforded none of the silylene addition products.  相似文献   

13.
设计并合成了一种对高压汞灯发射光谱中的h-线(405 nm)敏感的新型光致产碱剂(PBG)——N-{[(5-哌啶-2-硝基苄基)氧]-羰基}-2,6-二甲基哌啶(PNCDP).通过红外(IR)、核磁(NMR)以及元素分析对PNCDP的结构进行了表征.紫外-可见光谱(UV-Vis)测试结果表明,与传统的i-线(365 nm)敏感PBG——N-{[(4,5-二甲氧基-2-硝基苄基)氧]-羰基}-2,6-二甲基哌啶(DNCDP)相比,PNCDP的最大紫外吸收波长为395.5 nm,较DNCDP红移了52.5 nm.初步光刻实验表明,PNCDP对h-线具有较好的敏感度.  相似文献   

14.
A nondispersive vacuum ultraviolet atomic absorption spectrophotometer for mercury has been developed. A mercury electrodeless discharge lamp (EDL), which provided a significant radiant flux at both the main resonance line at 185.0 nm and the resonance-intercombination line at 253.7 nm, was utilized with a nitrogen-purged system and a CsI phototube. Because of its spectral response, the CsI phototube allowed it to measure effectively the mercury atomic absorption only at 185.0 nm. The dependence of the atomic absorption sensitivity on the EDL operational power was similar to that in a dispersive system. Since the nondispersive system allowed operation of the EDL with lower power compared with the dispersive system, better sensitivity could be obtained owing to less self-absorption of the resonance line. Furthermore, the low fluctuation noise of the light source led to a lower detection limit. The sensitivity and detection limit were 0.077 and 0.014 ng, respectively, and the relative standard deviation for 0.05 ng mercury was at most about 5.8%.  相似文献   

15.
Darby SB  Smith PD  Venables DS 《The Analyst》2012,137(10):2318-2321
Optical cavities are commonly used to increase the sensitivity of absorption measurements, but have not been extensively used below 300 nm, mainly owing to the limited light sources at these wavelengths. While some progress has been made using cavity ring-down spectroscopy, these systems rely on complex and expensive lasers. Here we investigate an approach combining Cavity-Enhanced Absorption Spectroscopy (CEAS) with an inexpensive low vapour pressure mercury lamp for sensitive absorption measurements at 253.7 nm. We demonstrate that the CEAS absorption in our system is 50 times greater than the absorption found in a single-pass configuration; using this approach, we obtained limits of detection of 8.1 pptv (66 ng m(-3)) for gaseous elemental mercury and 8.4 ppbv for ozone. We evaluate the performance of the system and discuss potential improvements and applications of this approach.  相似文献   

16.
TiO2 nanotube arrays (TNTs) electrode loaded with Zn nanoparticles was prepared by anodization and the size of Zn nanoparticle loaded on TNTs electrode was controlled bychronoamperometry deposition time. Results of SEM and XRD analysis show that Zn nanoparticles had a diameter of about 15-25 nm when the deposition time was 3-5 s. The UV-Vis diffuse reflectance spectra show the Zn loaded harvest light with 480-780 nm more effectively than the unloaded sample. The photocurrent response of Zn loaded TNTs electrodes were studied, the results showed that TNTs electrodes loaded with Zn nanoparti-cles has 50% increased photocurrent response under high-pressure mercury lamp irradiation compared with unloaded TNTs electrode.  相似文献   

17.
以中压汞灯为光源,采用吸收光谱法,观察了UO2(NO3)2•6H2O在DMF(N,N-二甲基甲酰胺)溶剂中光化还原时的吸收光谱随照射时间、铀浓度及溶液酸度的变化.经短时间光照后,在UO2(NO3)2-DMF溶液中有铀(Ⅴ)形成,其吸收峰在755和635nm处.结果表明,它们分别是UO2+-DMF和UOOH2+-DMF的特征吸收,溶液中铀(Ⅴ)的岐化反应与H+浓度密切相关,UOOH2+是岐化反应的中间体.  相似文献   

18.
管自生 《化学学报》2003,61(12):2025-2028
应用sol-gel法制备了TiO_2薄膜,在321 K和高湿度下应用500 W高压汞灯对薄 膜进行辐射处理,应用划痕法测定了薄膜的强度。利用红外光谱(IR)、拉曼光谱 (Raman)和接触角仪研究了光辐射对薄膜和结构和亲水性能的影响,结果表明高 湿度下紫外光辐射可以促使刚制备TiO_2薄膜中的羟基、有机基团脱落和Ti-O-Ti结 构生成,使TiO_2薄膜的强度、晶化程度显著提高和薄膜在可见光区域吸收增加。 刚制备的sol-gel TiO_2薄膜的亲水性能随着光辐射先是下降,然后上升,且各向 亲水同性。通过此方法可以在不耐温的基材上制备致密的高强度的和具有一定光致 亲水性能的初步晶化的TiO_2薄膜。  相似文献   

19.
ESR absorption has been observed in a single-crystal solid solution of acenaphthene in durene under irradiation at 120K with light from a high-pressure mercury lamp. The observed hyperfine structure gives evidence for hyperconjugation of the ethylene group protons. The guest and host molecular planes are nearly parallel to each other, and the guest in-plane axes deviate from the host ones by ca 40°. For comparison, 1,1,2,2-tetradeuteroacenaphthene was also prepared and studied.  相似文献   

20.
The photocatalysis effect of nanometer TiO2 particles and TiO2-coated ceramic plate on Hepatitis B virus surface antigen (HBsAg) was investigated. The ELISA (enzyme-linked immunosorbent assay) standard method was used to assess the efficiency of TiO2 material to destroy the HBsAg. The research has shown that the suspension of TiO2 (0.5g/L) can destroy most of the HBsAg under the irradiation of mercury lamp, with the light intensity of 0.6mW/cm(2) at 365nm wavelength, or under the sunlight irradiation for a few hours. TiO2-coated ceramic plates can also destroy the HBsAg under the irradiation of mercury lamp, with the light intensity of 0.05mW/cm(2) at 365nm wavelength or under the room daylight for a few hours.  相似文献   

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