C_(70)富勒醇的激光光解研究

用时间分辨激光光解技术对富勒烯水溶性衍生物C_(70)富勒醇［C_(70)（OH）_m］研究发现，与通常富勒烯衍生物，如C_(60)［C（COOEt）_2］_n，C_(60)（C_4H_6O），C_(60)（C_3H_7N）在溶液中光解常产生激发三重态不同，C_(70)富勒醇能被248nm激光单光子电离。以KI溶液为参照，测定其水合电子的量子产额（Ф_(e-)）为0．11。将激光光解与SO~-的氧化对比，确认了到C_(70)富勒醇阳离子自由基的吸收峰。     

C70富勒醇的激光解研究

用时间分辨激光光解技术对富勒烯水溶性衍生物Ｃ７０富勒醇研究发现，与通常富勒烯衍生物，如Ｃ６０「Ｃ（ＣＯＯＥｔ）２」ｎ，Ｃ６０（Ｃ４Ｈ６Ｏ）Ｃ６０（Ｃ３Ｈ７Ｎ）在溶液３中光解常产生激发三重态没，Ｃ７０富勒醇能被２４８ｎｍ激光单光子电离。以ＫＩ溶液为参照，测定其水合电子的量子产额为０．１１，将激光光解与ＳＯ４的氧化对比，确认了到Ｃ７０富勒醇阳离子自由基的吸收峰。     

细胞核靶向富勒醇固体脂质纳米粒对小鼠亚致死剂量辐射损伤的预防作用

为研究细胞核靶向富勒醇固体脂质纳米粒(C60(OH)24-SLN-E)对亚致死剂量60Coγ射线照射致小鼠辐射损伤的防护作用,采用SPF级雄性ICR小鼠,连续7天腹腔注射细胞核靶向富勒醇硬脂质纳米粒,于第7天送往辐照中心接受60Coγ射线全身均匀照射,照射剂量为6 Gy,照射剂量率为0.42 Gy/min,观察照后小鼠一般情况、体重变化,测定照后14天小鼠外周血液学参数的变化。结果表明,细胞核靶向富勒醇固体脂质纳米粒(C60(OH)24-SLN-E)能有效减轻亚致死剂量60Coγ射线所引起的小鼠体重、外周血白细胞的降低,还可以促进照射后小鼠骨髓红系造血的恢复,与照射对照组相比差异有统计学意义(p0.05)。说明细胞核靶向富勒醇固体脂质纳米粒(C60(OH)24-SLN-E)对受亚致死剂量60Coγ射线照射的小鼠具有一定的保护作用。     

~(67)Ga-C_(60)(OH)_x标记条件的研究

用^67Ga标记了水溶性富勒烯衍生物富勒醇（C60（OH）x）。研究了反应时间、温度、pH值、C60（OH）x的质量浓度等对标记率的影响。研究结果表明，反应时间在3-60min时对标记率影响不大；反应温度对标记率基本无影响；pH值大于12后，标记率较低；C60（OH）x的质量浓度高于5μg/μL时，标记率均在94%以上。稳定性研究结果表明，标记后稀释与不稀释的溶液在放置200h后，其放化纯度都达90%以上。     

紫外光照射下富勒醇对细胞的防护作用

为了解紫外辐射下富勒烯衍生物富勒醇对细胞的生物效应,利用四唑盐比色实验(MTT)法研究了富勒醇对紫外辐照细胞的存活率影响,紫外辐照细胞时富勒醇对细胞超氧化物岐化酶(SOD)和氧化产物丙二醛(MDA)的影响,同时比较了C60-PVP对紫外辐照细胞的辐射生物效应。结果表明,富勒醇能够有效的防护紫外辐射对细胞造成的损伤,其机理可能是富勒醇能够吸收紫外辐照产生的自由基,使细胞膜不被紫外辐照损伤。     

富勒醇对γ射线辐照贻贝棘尾虫保护作用的研究

本工作测定了^60Coγ射线6个辐照剂量(100、300、500、800、1200、1500Gy)与贻贝棘尾虫存活率响应曲线,发现辐照后第5d虫体的存活率分别下降到47％、18％、16％、8％、5％、3％左右。在此基础上重点研究了在富勒醇存在下,^60Coγ射线对贻贝棘尾虫的辐射损伤,结果表明在高、低剂量下富勒醇对虫体均产生保护作用,能明显提高贻贝棘尾虫受照射后的存活率,并且这种辐射防护作用与富勒醇浓度相关。富勒醇对贻贝棘尾虫的辐射防护可能基于其对自由基的清除反应,因而可能是一种潜在的辐射防护剂。     

C60衍生物的放射性碘标记

富勒烯C60是由60个碳原子组成的球型分子,包含12个五元环和20个六元环,直径为0.71nm.独特的结构赋予了它特殊的物理、化学和生物性质.C60是一个优良的电子接受体,通过光诱导产生单重态氧的效率高达100%,被喻为"单重态氧的发生器”.它极易与游离基反应,又被喻为"吸收游离基的海绵”.它具有30个双键,可以发生许多有机反应,连接各种化学药物,是药物设计的理想载体[1].C60仅溶于一些非极性和弱极性的有机溶剂,在水等极性溶剂中不溶.富勒烯作为药物载体,首先要制成水溶性衍生物.更为重要的是还必须了解它及其衍生物的基本药理性质,但这方面研究刚刚开始,研究结果报道甚少,其中一个原因是缺少对富勒烯及其衍生物的分析检测方法.Yamago[2]曾用14C标记C60衍生物,但由于14C核性质并不理想而且标记方法颇为复杂,其应用范围和研究结果均受限制.由于C60具有双键,可以进行碘标记.本工作制备了水溶性富勒烯衍生物C60(OH)xOy,然后采用Iodogen氧化法用125I标记了该衍生物,为今后药理研究,例如,在动物体内的吸收、分布、排泄、毒性等研究创造了条件.     

富勒烯乙二胺的抗辐射损伤性能

合成了一种水溶性富勒烯衍生物——富勒烯乙二胺,分别采用60 Co源和中子加速器等辐照装置,并结合红外光谱(FTIR)、电子自旋共振技术(ESR)和电喷雾质谱(ESI-MS)等表征手段,比较考察了富勒烯乙二胺与香兰素对受γ射线和中子等高能射线或粒子照射所产生自由基的清除性能。结果表明:对于经γ射线和中子辐照产生的自由基,所制得的富勒烯乙二胺均表现出了较好的抗辐射损伤特性;相同条件下对样品辐照所产生的自由基的清除性能明显优于市购的香兰素。     

富勒醇对贻贝棘尾虫的辐射防护机制

为进一步了解富勒醇对贻贝棘尾虫γ辐射防护的机制,在先前工作基础上测定了0．10mg mL^-1的富勒醇存在下,剂量为100-2000 Gy范围内贻贝棘尾虫辐照后第5d的存活率,并用光学和透射电子显微镜观察了辐照后贻贝棘尾虫形态和超微结构的变化,测定了与自由基相关的酶的活性（超氧化物歧化酶Superoxide dismutase,SOD和过氧化氢酶Catalase,CAT）和脂质过氧化产物（丙二醛Malondialdehyde,MDA和脂褐素Lipotusion,LIP）。结果表明,当剂量为100-1500 Gy时,富勒醇能明显提高贻贝棘尾虫γ辐照后的存活率,当剂量达到2000 Gy时,富勒醇对存活率无明显影响,表明富勒醇对贻贝棘尾虫γ辐射防护作用不仅和它浓度有关,而且与γ辐射剂量相关。显微镜观察结果在细胞和亚细胞层次揭示了贻贝棘尾虫辐射损伤的结构特征,并给出了富勒醇防护作用的附加证据。未加富勒醇辐照组中SOD和CAT的活性低于对照组（P〈0．01）,加富勒醇辐照组中SOD和CAT的活性明显高于未加富勒醇辐照组和对照组（P〈0．01,P〈0．01）,而加富勒醇辐照组中MDA和LIP的含量却显著低于对照组（P〈0．01,P〈0．05）和辐照组（P〈0．01）,由此推断富勒醇主要通过清除自由基,刺激SOD和CAT的活性,同时减少细胞膜上的脂质过氧化反应,达到对贻贝棘尾虫的辐射防护作用。     

富勒烯~(60)Co γ辐照的稳定性研究

为考察富勒烯基体的辐照稳定性,在不同氛围(空气氛围和密闭条件)中,富勒烯样品经受高剂量和高剂量率60Coγ射线的辐照.辐照后的样品经高效液相色谱(HPLC)和X射线衍射(XRD)分析,研究γ辐照对富勒烯成分及晶体结构的影响.结果显示,与对照样品相比,不同氛围的辐照对样品的组成和晶体结构均未造成影响,提示富勒烯在60Coγ射线辐照下具有相当好的稳定性.本工作还从理论上探讨了富勒烯经60Coγ辐照不发生组成及晶体结构改变的原因.     

C_(60)衍生物的放射性碘标记

富勒烯Ｃ6 0 是由 60个碳原子组成的球型分子 ,包含 1 2个五元环和 2 0个六元环 ,直径为0 .71ｎｍ。独特的结构赋予了它特殊的物理、化学和生物性质。Ｃ6 0 是一个优良的电子接受体 ,通过光诱导产生单重态氧的效率高达 1 0 0 % ,被喻为“单重态氧的发生器”。它极易与游离基反应 ,又被喻为“吸收游离基的海绵”。它具有 3 0个双键 ,可以发生许多有机反应 ,连接各种化学药物 ,是药物设计的理想载体[1] 。Ｃ6 0 仅溶于一些非极性和弱极性的有机溶剂 ,在水等极性溶剂中不溶。富勒烯作为药物载体 ,首先要制成水溶性衍生物。更为重要的是还必须了…     

Hybrid electric discharge plasma technologies for water decontamination: a short review

Electric discharge plasma (EDP) can efficiently degrade aqueous pollutants by its in situ generated strong oxidative species (·OH, ·O, H₂O₂, O₃, etc) and other physiochemical effects (UV irradiation, shockwaves, local high temperature, etc), but a high energy consumptions limit the application of EDP in water treatment. Some adsorbents, catalysts, and oxidants have been employed for enhancing the degradation of pollutants by discharge plasma. These hybrid plasma technologies offer improved water treatment performance compared to discharge plasma alone. This paper reviews the water decontamination performance and mechanisms of these hybrid plasma technologies, and some suggestions on future water treatment technologies based on discharge plasma are also proposed.     

Reactivity enhancement of chemical materials used in packed bed reactor of chemical heat pump

In this study, a mixture of expanded graphite (EG) and magnesium hydroxide (Mg(OH)₂) was used to enhance the thermal conductivity and reactivity of a magnesium oxide/water (MgO/H₂O) chemical heat pump, because EG is chemically stable and has high thermal conductivity and high moldability to form the heat exchange structure. Calcium chloride (CaCl₂) was also introduced into the mixture of EG and Mg(OH)₂ to ensure smooth diffusion of vapor in materials and enhance the fittability between EG and Mg(OH)₂. The reaction kinetics of pure Mg(OH)₂, a mixed material containing Mg(OH)₂ and CaCl₂ (termed MC), and a mixed material containing EG, Mg(OH)₂, and CaCl₂ (termed EMC) were examined under the same reaction conditions by performing thermobalance measurements. EMC exhibited a higher dehydration rate than the other materials. It also exhibited hydration reactivity at temperatures of up to 200 °C; at this temperature, pure Mg(OH)₂ exhibited low reactivity. The addition of CaCl₂ also enhanced the hydration reactivity of MgO because of the high water adsorption ability of CaCl₂ in EMC. A reaction rate equation for the hydration of EMC was proposed on the basis of an assumed reaction model. The thermal performance of a MgO/H₂O chemical heat pump manufactured using EMC was evaluated from this equation. EMC was concluded to have good potential for use as a packed bed material in the MgO/water chemical heat pump owing to its low cost, high hydration reactivity, high thermal conductivity, and high moldability to form the heat exchange structure.     

Water Content Effect on Oxides Yield in Gas and Liquid Phase Using DBD Arrays in Mist Spray

Electric discharge in and in contact with water can accompany ultraviolet (UV) radiation and electron impact,which can generate a large number of active species such as hydroxyl radicals (OH),oxygen radical (O),ozone (O3) and hydrogen peroxide (H2O2).In this paper,a non thermal plasma processing system was established by means of dielectric barrier discharge (DBD) arrays in water mist spray.The relationship between droplet size and water content was examined,and the effects of the concentrations of oxides in both treated water and gas were investigated under different water content and discharge time.The relative intensity of UV spectra from DBD in water mist was a function of water content.The concentrations of both O3 and nitrogen dioxide (NO2) in DBD room decreased with increasing water content.Moreover,the concentrations of H2O2,O3 and nitrogen oxides (NOx) in treated water decreased with increasing water content,and all the ones enhanced after discharge.The experimental results were further analyzed by chemical reaction equations and commented by physical principles as much as possible.At last,the water containing phenol was tested in this system for the concentration from 100 mg/L to 9.8 mg/L in a period of 35 min.     

Investigation on the stability of water-soluble ZnO quantum dots in KB cells by X-ray fluorescence and absorption methods

The structural stability of water-soluble ZnO quantum dots (QDs) in oral epidermoid carcinoma (KB) cells was studied by the External Micro Proton Induced X-ray Emission (External Micro-PIXE) technique and the X-ray absorption fine structure (XAFS) measurement. The External Micro-PIXE and XAFS experiments were respectively performed at the JAEA and the Shanghai Synchrotron Radiation Facility. The elements’ distributions were detected by the External Micro-PIXE technique. The XAFS method was applied to obtain information about zinc (Zn) K-edge spectra. The fits of the XAFS data showed that the Zn-O bond structure of water-soluble ZnO QDs was stable after being absorbed by KB cells. Its local structural parameters were almost identical with those of the standard wurtzite structure. Water-soluble ZnO QDs had good structural stability in KB cells.     

67Ga标记C60衍生物C60(OH)x的生物分布研究

运用放射性核素^67Ga标记技术研究了富勒烯衍生物C60(OH)x在小鼠体内的分布和代谢。研究结果表明，标记物很快被体内各脏器和组织摄取，主要分布在骨髓、骨、肝脏和脾中；肌肉和皮毛较少，不能通过血脑屏障，从血液及其他脏器中清除较慢，末发现急性毒性。结果提示该衍生物具有微粒状特性，有望用作淋巴显像剂或恶性淋巴肿瘤导向治疗的药物载体。     

Significance of Covariance Matrices in Nuclear Data Evaluation

Tritium decontamination using ultra violet (UV) lamp and laser was performed. Simulated co-deposited layer on tungsten substrate was deposited by C₂H₂ or C₂D₂ glow discharge. The co-deposited layer was irradiated to UV lights from a xenon excimer lamp (172 nm) or ArF excimer laser (193 nm) and the in-situ decontamination behavior was evaluated by a mass spectrometer. After the UV irradiation, the hydrogen concentration in the co-deposited layer was evaluated by elastic recoil detection analysis (ERDA) and the depth profile was analyzed by secondary ion mass spectrometry (SIMS).

For the co-deposited layer formed by C₂D₂ glow discharge, it was found that M/e 3 (HD) gas was released mainly during the UV lamp irradiation while both M/e 3 (HD) and M/e 4 (D₂) gases were detected during the UV laser irradiation. Though the co-deposited layer was not removed by UV lamp irradiation, almost all the co-deposited layer was removed by UV laser irradiation within 1 min. The ratio of hydrogen against carbon in the co-deposited layer was estimated to be 0.53 by ERDA and the number of photon needed for removing 1 fim thick co-deposited layer was calculated to be 3.7×10¹⁸ cm^-2 for the UV laser by SIMS measurement. It is concluded that C-H (C-D) bond on the co-deposited layer were dissociated by irradiation of UV lamp while the co-deposited layer itself was removed by the UV laser irradiation.     

UV照射对径迹蚀刻过程的影响

Truck technology depends decisively on the track structure of the material after irradiation. In order to reveal microstructures of the ion-tracks, many techniques have been applied to characterize the track. Conductometrie method is wildly used in the area as it can monitor in-situ the pore formation and growth processes that are closely related to structures of the ion track[1].In this study, polyethylterephthalate films (PET, 38 μm thick) were irradiated with Xe ions of 450 MeV, 3 × 105ions/cm2. Before etching with aqueous 0.3 M NaOH solution at 40℃, the samples were illuminated with UV light (λ＞310nm) in air for different time durations. Pore growth processes during the etching were monitored by the conductometric measurement. Fig. 1 shows the measurement results of radial etching rate of the pore growth in dGl/2/dt (Ω-1/2s-1) with the etching time.a. Without UV illumination, b. UV illuminated for 60 min, c. UV illuminated for 180 min, d. UV illuminated for 720 min As shown in Fig. 1, the etching processes changed dramatically with UV illumination time. (1) The break through time reduced with increased sensitization time, from 8× 104S of the control to about 1 × 104s of the 720 minutes UV illumination. (2) With increased UV illumination time, the shape of the pore growth rate curve changed greatly, f-mally became a shape with a peak and a vale. Formation of the peak implies that pores tended to break-through on completing the UV-light illumination, whereas the vale can be related to the slower etching rate in the track halo where most molecules had been crosslinked by the heavy ion irradiation. After etching for sufficient long time, the pore grew at a constant rate determined by the bulk etching rate.To interpret the measurements, numerical analysis and fitting were carried out, from which information related to the track structures and variations with the UV illumination was obtained.     

A Method of In-Pile Calorimetry

In order to immobilize Cs into pollucite structure, hydrothermal reactions of Cs with amorphous aluminosilicate (siliceous sinter) and with mixtures of low-quartz (silicastone) and Al(OH)₃, were performed. In both cases, pollucite was formed in 5-N NaOH solution above 200°C for 10 min. Synthesized pollucite was solid solution between pollucite and analcite. Waste forms in which Cs was immobilized in pollucite structure were successfully produced by the hydrothermal hot-pressing method using the silica matrix (mixture of low-quartz and amorphous aluminosilicate) containing Al(OH)₃ and NaAlO₂. Effect of hot-pressing conditions on leachability of the waste forms was investigated. The waste form containing 10w/o CsOH produced at 300°C and 49 MPa for 24 h, had Cs leach rate of 3.15 g/m²·d by Soxhlet leach tests for 7 d. The waste form was porous, but had high compressive strength and thermal stability.     

电子束辐照制备Pd/TiO2光催化薄膜

用电子束辐照浸泡在浓度分别为1×10-5、1×10-4、1×10-3、1×10-2和1×10-1mol/L的PdCl2溶液中的TiO2薄膜,在TiO2薄膜表面形成Pd纳米颗粒.通过X射线衍射(X-ray diffractometry,XRD)、场发射扫描电镜(Field emission scanning electron microscope,FESEM)、X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)和紫外可见(Ultraviolet visible,UV-Vis)吸收光谱对辐照后的Pd/TiO2薄膜进行表征.分析表明,TiO2薄膜表面上沉积了直径20-50 nm的颗粒,为面心立方结晶的金属Pd;Pd/TiO2薄膜的UV-Vis光谱吸收边向可见光方向发生了偏移.用甲基橙作为光催化降解反应物,研究了Pd/TiO2薄膜分别在紫外光、可见光作用下的光催化降解效率.结果表明,Pd/TiO2薄膜的光催化能力显著地提高,在紫外光、可见光作用下的光催化效率分别提高了2.25倍和3.4倍.