基于杂交链式反应辅助多重信号放大的端粒酶灵敏检测

端粒酶是真核细胞维持端粒长度的关键逆转录酶,其生物活性的高低可以为多种癌症的临床诊断和预后治疗提供有价值的信息.本研究以人宫颈癌细胞(HeLa细胞)裂解液中的端粒酶为研究对象,通过借助杂交链式反应辅助多重信号放大策略,提出了一种新颖、灵敏的检测端粒酶电化学方法.首先将端粒酶的延伸引物自组装在金电极表面,当端粒酶存在时,端粒酶能够催化引物的延伸,产生与发卡环探针H1部分互补的序列,进而引发杂交链式反应,形成由两个发卡环探针(H1和H2)交替杂交而形成的DNA长链.由于H1和H2末端均修饰有生物素,加入链霉亲和素修饰辣根过氧化物酶后,辣根过氧化物酶被被连接到电极表面,催化邻苯二胺氧化生成2,3-二氨基吩嗪,产生显著的电化学信号.实验结果表明,本研究建立的端粒酶电化学检测方法高效、可行,线性范围宽,灵敏度高,可以检测每毫升10个HeLa细胞裂解液中的端粒酶.本方法具有较好的选择性,能有效区分端粒酶和对照蛋白.     

基于电子顺磁共振的锶铁氧体磁特性研究

为了研究配料、温度、氧环境和掺杂等条件对锶铁氧体的磁性能的影响问题, 利用溶胶-凝胶法制备了锶铁氧体粉末, 建立了一种基于电子顺磁共振技术研究锶铁氧体粉末的磁特性的方法. 用电子顺磁共振波谱仪对烧结后的产物进行测试发现: 400 ℃预烧下, 锶铁摩尔比为1:9时, 中间产物顺磁相α-Fe₂O₃含量最多, 高于400 ℃时其含量减少, 亚铁磁相增加, 并确定最佳煅烧温度介于800-900 ℃. 这是由于外磁场和其他磁场综合作用产生亚铁磁相, 进而产生较强的磁矩相互作用所致. 结合工业实际应用, 发现缺氧退火环境下, 顺磁相α-Fe₂O₃含量较大, 不利于亚铁磁相生成; X-射线衍射(XRD)表征结果表明: 除了少量杂相, 其余均为顺磁相和亚铁磁相; 电子顺磁共振谱和XRD 谱检测结果综合表明, 锶铁摩尔比为1:9时, 最终产物的顺磁相含量最少, 亚铁磁相含量最多, 磁性最强; 毫特斯拉计的剩磁检测结果也证实了上述结果. 掺杂实验发现镧离子占锶镧总摩尔数的20% 至30% 时, 能够有效降低顺磁相的产生, 增强最终产物的亚铁磁性.     

基于纳米SnO2材料的二维纳米催化发光传感器研制及其测定甲基叔丁基醚的应用

以碳纳米管(CNT)为模板,采用液相沉积法可控合成了SnO2-CNT复合纳米材料、SnO2纳米棒两种形貌的SnO2纳米材料,研究了它们对甲醇、MTBE催化发光的影响.通过考察两种不同形貌SnO2纳米材料的结构、比表面积与其催化发光的关系,建立了一种二维纳米催化发光传感器,并测定了MTBE产品的纯度和其中的甲醇含量,甲醇...     

All-solid silica-based photonic crystal fibers

An index-guiding all-solid photonic crystal fiber (PCF) composed entirely of silica material is proposed in this paper. The core of this optical fiber is composed of pure silica, and the cladding consists of doped silica rod in the background of pure silica. The dependence of confinement loss on the diameter of the doped rods, the number of doped-rod rings, and the doping level is investigated numerically. In addition, the proposed fiber possesses a shorter cutoff wavelength as compared with the air/silica PCF, which is directly confirmed by the V parameter, and explained based on a scalar approximation method. Furthermore, the bending loss for the fiber is predicted. A low-loss single-mode all-solid silica-based PCF with a large-mode-area is possible by the appropriate selection of configuration parameters.     

跨声速离心压气机机匣处理扩稳研究

高增压技术是高升功率车用内燃机的主要技术瓶颈之一,其核心难点在于高压比离心压气机内部复杂跨声速流动导致稳定运行范围窄,无法满足车用工况在高压比条件下对稳定运行工作范围的要求。为拓宽跨声速离心压气机的稳定工作范围,利用全三维数值模拟研究了机匣处理几何参数对扩稳的作用规律及机理。试验结果表明,采用优化后的机匣处理结构,压气机稳定工作范围由20.8%提高到33.6%。     

有序介孔SiO2的制备及其在色谱填料方面的应用

利用水热合成方法,在低浓度盐酸下用三嵌段共聚物EO106PO70EO106（F127）作为模板剂,在100℃,130℃和150℃的条件下,制备了3种笼型介孔二氧化硅.通过粉末N2气吸附-脱附实验表征其孔径（PD）及比表面积（BET）、扫描电镜（SEM）观察其表面形貌、透射电子显微镜（TEM）分析其微观结构;通过表征结果分析,该材料具有笼型介孔结构.同时,将该介孔材料应用在色谱分离方面,对氯苯,苯乙烯,1,2-二苯乙烯,联苯4种物质混合物进行分离,与其他多种二氧化硅材料比较,150℃的条件下合成的KIT-5-150分离效果最好.     

Analysis of Components of Fatty Acids and Determination of Methyl Hexade Canate in Honeycomb

Honeycombs are nests of polistes olistes olivaceous, polistes japonicus saussure or parapolybia varia Fabricius. They can drive out wind, attack toxicity, kill microbe,restrain ache, accelerate blood coagulation, strengthen heart beats and reduce blood pressure.They have been used as the important ingredient in the treatment of cancer in recent years. Honeycomb contains a number of chemical ingredient, mainly of beewax, resin and volatile oil.Though honeycomb have been widely used in the medicine,the components of fatty acids in honeycomb oil and the controlling method of quality of honeycomb have not been reported. GC/MS method for the qualitative and quantitative analysis of fatty acids in honeycomb oil have been adopted in this report and the method with analyzing methyl hexade canate in honeycomb are set up in order to exploit and use better honeycombs.     

Experimental investigations of mechanical and reaction responses for drop-weight impacted energetic particles

Low-velocity drop-weight impact experiments on individual and multiple Cyclotetramethylene tetranitramine (HMX) energetic particles were performed using a modified drop-weight machine equipped with high-speed photogra-phy components. Multiple particles experienced more severe burning reactions than an individual particle. Comparisons between impacted salt and HMX particle show that jetting in HMX is mainly due to the motion of fragmented parti-cles driven by gaseous reaction products. Velocity of jetting, flame propagation, and area expansion were measured via image processing, making it possible to quantify the chemi-cal reaction or mechanical deformation violence at different stages.     

ICP-AES测定高纯碲中11种杂质元素

电感耦合等离子体原子发射光谱法 (ICP- AES)同时测定高纯碲中 11种杂质元素。用离峰扣背景法消除背景干扰 ,检出限能满足高纯碲中杂质元素的测定要求 ,加标回收率在 94 .0 %— 10 8%之间。