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Imaging of Activity of Horseradish Peroxidase at β-Cyclodextrin Polymer by Scanning Electrochemical Microscopy 被引量:13
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作者 XiaoLeiWANG YongXiangSHI +1 位作者 ZengLiangBAI WenRuiJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第2期214-215,共2页
The activity of horseradish peroxidase at b-cyclodextrin polymer was imaged by scanning electrochemical microscopy using 3, 3’, 5, 5’-tetramethylbenzide and H2O2 as the substrates.
关键词 山葵过氧化酶 Β-环糊精 扫描电化学显微镜 培养基
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Electrochemical Oxidation of L-Cystenine in SDS/BA/H_2O Microemulsion 被引量:3
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作者 LIZhong-chun LIUTian-qing GUORong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第3期322-325,共4页
The electrochemical oxidation of L-cysteine in an SDS/BA/H2O microemulsion system was studied with the methods of ultramicroelectrode cyclic voltammetry and AC impedance. The catalytic efficiency of the microemulsion ... The electrochemical oxidation of L-cysteine in an SDS/BA/H2O microemulsion system was studied with the methods of ultramicroelectrode cyclic voltammetry and AC impedance. The catalytic efficiency of the microemulsion on the electrochemical oxidation increases with the increase of BA or SDS content, but decreases with the increase of the water content because of the effects of BA, SDS and water on the solubilization of L-cysteine in the microemulsion. Furthermore, the catalytic efficiency of the bicontinuous structure is greater than that of an O/W microemulsion system. The results derived from both the rate constant k0 and Gibbs free energy ΔG≠ accord with those from the catalytic efficiency. 展开更多
关键词 电化学氧化 微乳状液 十二烷基硫酸钠 SDS/BA/H2O 超微电极 伏安法 L-半胱氨酸
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Enhanced Photocatalytic Efficiency of TiO2 by Combining the Modification of Ag Nanoparticles with the Application of Anodic Bias 被引量:3
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作者 ChunHE YaXIONG +1 位作者 DongSHU XiHaiZHU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第5期539-542,共4页
Ag-TiO2/ITO film electrode was used as photoanode to investigate the feasibility of a hybrid technology of Ag nanoparticles combined with the application of anodic bias. The results showed that the deposited Ag and ap... Ag-TiO2/ITO film electrode was used as photoanode to investigate the feasibility of a hybrid technology of Ag nanoparticles combined with the application of anodic bias. The results showed that the deposited Ag and applied anodic bias have an apparent additive effect. 展开更多
关键词 二氧化钛 光催化活性 薄膜电极 纳米粒子 阳极 光催化作用 蚁酸
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Synthesis of a New Porphyrin-fluorescein Hybrid and its Supramolecular Self-assembly with Amino-porphyrinatomanganese(Ⅲ) by Hydrogen-bonding 被引量:3
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作者 JiaZhengLU JinWangHUANG LiFenFAN JieLIU KeZhuanXU XianLiCHEN LiangNianJI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期303-306,共4页
A new porphyrin-fluorescein hybrid 2 (Fl-PPTPP) has been synthesized and characterized by UV-Vis, IR, H-NMR, ESI-MS and elemental analysis. The supramolecular 1 self-assembly of Fl-PPTPP with amino-porphyrinatomangane... A new porphyrin-fluorescein hybrid 2 (Fl-PPTPP) has been synthesized and characterized by UV-Vis, IR, H-NMR, ESI-MS and elemental analysis. The supramolecular 1 self-assembly of Fl-PPTPP with amino-porphyrinatomanganese [Mn (p-APTPP)Cl] by hydrogen-bonding was studied using fluorescence spectroscopic titration and ESI-MS. 展开更多
关键词 合成 卟啉 荧光素 超分子自组装 氨基-卟啉锰(Ⅲ) 氢键
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Two New Sequiterpenoids from Helicteres angustifolia 被引量:3
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作者 XinDongGUO ZhiShuHUANG +3 位作者 YaDanBAO LinKunAN LinMA LianQuanGU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第1期49-52,共4页
A new sesquiterpenoid lactone, 3,6,9-trimethyl-pyrano[2,3,4-de]chromen-2-one (1) and a novel sesquiterpenoid quinone, 6-[2-(5-acetyl-2,7-dimethyl-8-oxo-bicyclo[4.2.0]octa-1,3,5- trien-7-yl)-2-oxo-ethyl]-3,9-dimethylna... A new sesquiterpenoid lactone, 3,6,9-trimethyl-pyrano[2,3,4-de]chromen-2-one (1) and a novel sesquiterpenoid quinone, 6-[2-(5-acetyl-2,7-dimethyl-8-oxo-bicyclo[4.2.0]octa-1,3,5- trien-7-yl)-2-oxo-ethyl]-3,9-dimethylnaphtho[1,8-bc]pyran-7,8-dione (2) together with a known perezone (3) were isolated from the roots of Helicteres angustifolia. The structures were elucidated as mainly on the basis of 1D and 2D NMR spectroscopic data. 展开更多
关键词 倍半萜化合物内酯 倍半萜化合物醌 山芝麻 传统中药 药物提取
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Selenium Nanoparticles Prepared from Reverse Microemulsion Process 被引量:3
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作者 MingZhuLIU ShengYiZHANG YuHuaSHEN MingLiangZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第10期1249-1252,共4页
Selenium nanoparticles were prepared by a reverse microemulsion system. Sodium selenosulfate was used as selenium source. The results showed that hydrochloric acid concentration and reaction temperature had great infl... Selenium nanoparticles were prepared by a reverse microemulsion system. Sodium selenosulfate was used as selenium source. The results showed that hydrochloric acid concentration and reaction temperature had great influence on the morphology of products. The crystalline selenium nanowires and amorphous selenium nanorods were obtained in given condition. 展开更多
关键词 纳米粒子 反向微乳液系统 制备
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Structure and Properties of Self-reinforced Material Made from Ultra-high Molecular Weight Polyethylene-montmorillonite Nanocomposite 被引量:3
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作者 WANGQing-zhao LIAOXian-ling LIUZong-lin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期504-510,共7页
High-strength and high-modulus ultra-high molecular weight polyethylene(UHMWPE), named self-reinforced material, was obtained by the elongation of UHMWPE-montmorillonite nanocomposite at melting temperature. Accordi... High-strength and high-modulus ultra-high molecular weight polyethylene(UHMWPE), named self-reinforced material, was obtained by the elongation of UHMWPE-montmorillonite nanocomposite at melting temperature. According to the scanning electron microscope(SEM) analysis, a great deal of fibrillar texture formed in the direction of elongation, and the tensile fractured surface was similar to that of highly oriented fiber. The transmission electron microscope(TEM) and selective area electron diffraction(SAED) analyses reveal that the reinforced phase of the self-reinforced material is an extended chain crystal and its size is about 50200 nm wide and several microns long, and the montmorillonite layers are broken up to pieces in the size from 100 to 10 nm. The broken layers which have a huge surface area interacting strongly with macromolecules reduces the entanglement density of UHMWPE and induces the chain orientation in flow field. It is supposed that the astriction of montmorillonite layers to polyethylene chains is not only end-tethered but also side-tethered. The differential scan calorimetry(DSC) analysis shows that there are two endothermal peaks for the self-reinforced material, of which the peak at a higher temperature(136.4 ℃) is ascribed to the melting of the reinforced phase. 展开更多
关键词 聚乙烯 蒙脱石 纳米复合物 结构 性质 自加固材料
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Surface-treatment of Alkaline Earth Sulfides Based Phosphor 被引量:2
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作者 GUOChong-feng CHUBen-li XUJian SUQiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期253-257,共5页
A series of alkaline earth sulfides based phosphors Ca 0.8 Sr 0.2 S∶Eu 2+ ,Tm 3+ were covered with a layer of protective coating with alkaline earth fluorides by heating the mixture of phosphor and NH4HF2 at elevated... A series of alkaline earth sulfides based phosphors Ca 0.8 Sr 0.2 S∶Eu 2+ ,Tm 3+ were covered with a layer of protective coating with alkaline earth fluorides by heating the mixture of phosphor and NH4HF2 at elevated temperatures. The coatings were characterized by means of XRD and SEM. The optical properties of the coated phosphors and the influences of the coating on their properties have been discussed extensively. The stabilities of the coated and uncoated phosphors have been compared. 展开更多
关键词 碱土金属 硫化物 荧光体 涂层 表面处理
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Collecting property of diphosphonic acid for niobite 被引量:2
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作者 HaoRen FeifeiJi GuilanSong ShuxiangZhang 《Journal of University of Science and Technology Beijing》 CSCD 2005年第2期106-110,共5页
The effect of several collectors on the niobite synthetized under the condition of varying pH values and dosages were studied. The collecting property of several representative collectors was also investigated. The ex... The effect of several collectors on the niobite synthetized under the condition of varying pH values and dosages were studied. The collecting property of several representative collectors was also investigated. The experimental result shows that di- phosphonic acid is a good collector for niobite. Its recovery is about 84.24%-91.17% when the pH value of the pulp is less than 5.0 and the dosage of diphosphonic acid is 140 mg/L. The sequences of the selectivity and collecting capacity of the collectors were compared. Infrared absorption spectrum (IAS) and X-ray photoelectron spectroscopy (XPS) were used to detect and analyze the ad- sorption mechanism of diphosphonic acid on the surface of niobite. The IAS result indicates that diphosphonic acid is indeed ad- sorbed on the surface of niobite, and the XPS result shows that the binding energy of P2p peak of niobite treated by diphosphonic acid has changed 2.85 eV. It confirms that the adsorption belongs to a chemisorption type. 展开更多
关键词 铌铁矿 电磁光谱特征 白云石 矿物 分析方法
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Synthesis and Characterization of Novel Multifunctional Acylthiourea Polymers 被引量:1
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作者 XuePuMAO JinFengHUANG +4 位作者 ZhiFangDUAN ZhiYunDU ZhiShuHUANG LinMA LianQuanGU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期609-612,共4页
Several thiourea polymers have been synthesized through the reaction of diamine with 1, 4- or 1, 3- benzenedicarbonyl chloride and ammonium thiocyanate by solid-liquid phase transfer catalysis of polyethylene glycol-4... Several thiourea polymers have been synthesized through the reaction of diamine with 1, 4- or 1, 3- benzenedicarbonyl chloride and ammonium thiocyanate by solid-liquid phase transfer catalysis of polyethylene glycol-400 (PEG-400). The polymers were characterized and identified by elemental analysis, IR, 1HNMR and GPC. The multifunctional polymers have potential value as an ideal support for immobilized enzymes. 展开更多
关键词 合成方法 结构特征 聚合物 酰基硫脲 固-液相转移催化技术 生物活性 杀虫剂 植物生长调节剂
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The Study of Electrochemical Behavior of Dopamine at Nano-gold Modified Carbon Fiber Electrode 被引量:1
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作者 HongZHANG BaoKangJIN XiaoYanJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第7期737-739,共3页
The electrochemical behaviors (cyclic voltammetry, CV and different pulse voltammetry, DPV) of dopamine (DA) were studied in this paper. The result indicated that the oxidation of dopamine was controlled by diffusion ... The electrochemical behaviors (cyclic voltammetry, CV and different pulse voltammetry, DPV) of dopamine (DA) were studied in this paper. The result indicated that the oxidation of dopamine was controlled by diffusion and adsorption simultaneously at nano-gold (NG) modified carbon fiber electrode (CFE). This modified electrode can separate the peak potentials of dopamine and ascorbic acid (AA). The peak current of DA in DPV curve was found to be linearly proportional to the concentration of DA at range of 2.0?0-6~1.5?0-5mol/L and 1.0?0-5~5.0?0-4mol/L, respectively. 展开更多
关键词 多巴胺 纳米金修饰碳纤维电极 电化学行为 伏安法 微电极 神经递质 检测
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Enantiomeric Separation of Epinephrine and Salbutamol by Micellar Electrokinetic Chromatography Using β-Cyclodextrin as Chiral Additive 被引量:1
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作者 YanPengZHENG JinYuanMO 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第10期1209-1211,共3页
Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were de... Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were detected by electrochemistry using gold microelectrode at +0.65 V versus SCE reference electrode. The effects of detection potential, concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and applied voltage were discussed. 展开更多
关键词 肾上腺素 柳丁氨醇 胶体电动色谱 Β-环糊精 手性添加物 分离 电化学检测
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Electrochemical Detection of Alkaline Phosphatase in BALB/c Mouse Fetal Liver Stromal Cells with Capillary Electrophoresis 被引量:1
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作者 XueMeiSUN DongLI +1 位作者 ZengLiangBAI WenRuiJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第2期212-213,共2页
A method for determination of alkaline phosphatase (ALP) in BALB/c mouse fetal liver stromal cells has been described based on the catalytic reaction. After the cell extract is incubated with the substrate disodium ph... A method for determination of alkaline phosphatase (ALP) in BALB/c mouse fetal liver stromal cells has been described based on the catalytic reaction. After the cell extract is incubated with the substrate disodium phenyl phosphate, the reaction product phenol generated by ALP is determined by capillary electrophoresis with electrochemical detection. 展开更多
关键词 电气化学探测 碱性磷酸酶 胎儿 肝脏 基质细胞 毛细电泳
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Electrodeposition of Pr-Fe alloy films in urea-dimethylsulfoxide 被引量:1
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作者 ZHOUHao KEQinfang HUANGKaisheng LIUGuankun YUANDingsheng 《Rare Metals》 SCIE EI CAS CSCD 2005年第1期37-41,共5页
Cyclic voltammetry and chronoamperometry were used to investigate the electrochemical behavior of Pr^3+ ions in a system of 0.01 mol-dm-3 Pr(CH3SO3)3 + 0.01 mol-dm^-3 FeCl2+ 3.0 mol.dm^-3 urea + DMSO on a Pt electrode... Cyclic voltammetry and chronoamperometry were used to investigate the electrochemical behavior of Pr^3+ ions in a system of 0.01 mol-dm-3 Pr(CH3SO3)3 + 0.01 mol-dm^-3 FeCl2+ 3.0 mol.dm^-3 urea + DMSO on a Pt electrode. Some electrochemical parameters were measured. Potentiostatic depositions between -1.6 and -2.4 V were applied to deposit Pr-Fe films in urea-DMSO mixed solution. The Pr content in the alloy films was in the range of 34.89 wt.% to 37.15 wt.%.The Pr-Fe alloy films are proven to be amorphous by XRD (X-ray diffraction). 展开更多
关键词 电沉积工艺 镨-铁合金 薄膜 尿素-二甲亚砜 电化学性能
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Synthesis and Characterization of Star-like Liquid Crystals Centered by Silicon 被引量:1
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作者 JianQiangLIU QiZhenZHANG JingZhiZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第12期1423-1426,共4页
The synthesis and characterization of two new star-like liquid crystals are reported. They are made of a silicon core and four alkoxyazobenzene monomers in the periphery. Theirp hase behaviors and the structures are d... The synthesis and characterization of two new star-like liquid crystals are reported. They are made of a silicon core and four alkoxyazobenzene monomers in the periphery. Theirp hase behaviors and the structures are determined by infrared absorption spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), elemental analysis (EA), polarizing optical microscope (POM) and differential scanning calorimetry (DSC). 展开更多
关键词 合成 液晶 相行为 星形 烷氧基偶氮苯 结构鉴定
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One-dimensional Chain Dibenzo-18-crown-6 Complex: [K(DB18-C-6)]_2[Pt(SCN)_6]·2H_2O·C_2H_4Cl_2 Assembled by Cation-π Interactions 被引量:1
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作者 ZHUYue-hua DUMao-xi +2 位作者 LIDa-cheng WANGDa-qi DOUJian-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期123-126,共4页
关键词 一维空间链 冠醚配合物 二苯基-18-冠-6 [K(DB18-C-6)2[Pt(SCN)6·2H2O·C2H4Cl2 阳离子-Π相互作用
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Syntheses and Crystal Structures of Two VO(IV) Schiff Base Complexes with Oxyammonia Ligand 被引量:1
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作者 LILian-Zhi XUTao WANGDa-Qi NIUMei-Ju JIHai-Wei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第8期865-869,共5页
Two novel VO(IV) Schiff base complexes, VO(SALHA)2[SALHA: salicyaldehyde- oxyammonia] and VO(o-VANHA)2 [o-VANHA: o-vanillin-oxyammonia], have been synthesized with salicyaldehyde or o-vanilline, hydroxylammonium chlor... Two novel VO(IV) Schiff base complexes, VO(SALHA)2[SALHA: salicyaldehyde- oxyammonia] and VO(o-VANHA)2 [o-VANHA: o-vanillin-oxyammonia], have been synthesized with salicyaldehyde or o-vanilline, hydroxylammonium chloride and vanadyl sulfate in absolute methanol, and their crystal structures were determined by single-crystal X-ray diffraction. The vanadium(IV) centers in both complexes are five-coordinate in a distorted square pyramidal geometry. VO(SALHA)2 (C14H12N2O5V, Mr = 339.20) crystallizes in the monoclinic system, space group P21/n with a = 14.716(9), b = 7.175(5), c = 14.716(9) ? b = 113.130(7), V = 1428.8(15) 3, Z = 4, Dc = 1.577 g/cm3, l = 0.71073 ? m(MoKa) = 0.720 mm-1, F(000) = 692, the final R = 0.0466 and wR = 0.0829 for 1561 observed reflections (I > 2s(I)). VO(o-VANHA)2 (C16H16N2O7V, Mr = 399.25) is of monoclinic, space group P21/n with a = 11.386(12), b = 10.405(10), c = 14.627(15) , b = 93.654(19), V = 1729(3) 3, Z = 4, Dc = 1.533 g/cm3, l = 0.71073 , m(MoKa) = 0.615 mm-1, F(000) = 820, the final R = 0.0513 and wR = 0.1129 for 1235 observed reflections (I > 2s(I)). 展开更多
关键词 合成 晶体结构 钒配合物 席夫碱 氢氧化胺
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Electrochemical formation of holmium-cobalt alloys 被引量:1
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作者 SUYuzhi YANGQiqin LIUGuankun 《Rare Metals》 SCIE EI CAS CSCD 2003年第1期19-24,共6页
The electrochemical formation processes of holmium-cobalt alloys on cobalt cathode in molten HoC13-KC1 wereinvestigated by cyclic voltammetry and open current potential-time curve after potentiostatic electrolysis. Th... The electrochemical formation processes of holmium-cobalt alloys on cobalt cathode in molten HoC13-KC1 wereinvestigated by cyclic voltammetry and open current potential-time curve after potentiostatic electrolysis. The structure ofHo-Co alloys' films deposited on cobalt electrode by potentiostatic electrolysis was characterized by X-ray diffraction. Thestandard Gibbs free energies of formation for the intermetallic compounds of Ho and Co were determined. The diffusioncoefficient and diffusion activation energy of Ho atom in the alloy phase were calculated to be 10-10-10-11 cm2/s and 96.0kJ/mol, respectively, from the current-time curve at potential step. 展开更多
关键词 钬钴合金 吉布斯自由能 扩散系数 组成 稀土 测定
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Cyclic Voltammetry Determination of Epinephrine with a Nano-gold Modified Glassy Carbon Electrode in the Presence of High Concentration Ascorbic Acid 被引量:1
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作者 HongZHANG XueQinGUI 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第2期153-156,共4页
Nano-gold (NG) modified glassy carbon electrodes (GCEs) were used for determination of epinephrine (EP) in the presence of high concentration ascorbic acid (AA) by cyclic voltammetry (CV). This modified electrode can... Nano-gold (NG) modified glassy carbon electrodes (GCEs) were used for determination of epinephrine (EP) in the presence of high concentration ascorbic acid (AA) by cyclic voltammetry (CV). This modified electrode can not only catalytically oxidize EP and AA, but also separate the catalytic peak potentials of EP and AA by about 183.5 mV. In pH = 7.0 ogisogate byffer solution, the linear range of epinephrine was 5 ′ 106 ~ 1 × 10-4 mol/L. 展开更多
关键词 循环伏安法 肾上腺素 纳米金修改玻璃状碳电极 高浓度抗坏血病维生素
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Estimation of Critical Rate of Temperature Rise for Thermal Explosion of First Order Autocatalytic Decomposition Reaction Systems by Using Non-isothermal DSC 被引量:1
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作者 GUOPeng-jiang HURong-zu +8 位作者 ZHANGHai XIAZhi-ming SONGJi-rong GAOSheng-li NINGBin-ke SHIQi-zhen LIURong LUGui-e JIANGJi-you 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第2期163-165,共3页
A method of estimating the critical rate of temperature rise for the thermal explosion of first order autocatalytic decomposition reaction systems by using non-isothermal DSC is presented. The information was obtained... A method of estimating the critical rate of temperature rise for the thermal explosion of first order autocatalytic decomposition reaction systems by using non-isothermal DSC is presented. The information was obtained on the increasing rate of temperature for the first order autocatalytic decomposition of nitrocellulose containing 13.86% nitrogen converting into the thermal explosion. 展开更多
关键词 第一位自催化分解反应 热分解 热爆炸 温升临界速率 DSC
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