Cd2Ge7O16中Tb的长余辉发光特性

本文研究了Cd₂Ge₇O₁₆∶Tb³⁺材料的发光及其长余辉性质。指出Tb³⁺的发光是该离子的 ⁵D₃- ⁷D_J、 ⁵D₄- ⁷D_J两种跃迁产生的；随着掺杂浓度的增加 ⁵D₄- ⁷D_J跃迁增强，发光颜色由蓝变绿。并把该材料的长余辉性质归结为基质结构中有电子陷阱和空穴陷阱。提出余辉机理模型。     

Ionic Liquid Based Electrolyte with Mesoporous Silica SBA-15 as Framework for Quasi-solid-state Dye-sensitized Solar Cells

Quasi-solid-state electrolytes were fabricated with mesoporous silica SBA-15 as a framework material. Ionic conductivity measurements revealed that SBA-15 can enhance the conductivity of the quasi-solid-state electrolyte. The diffusion coefficients of polyiodide ions such as Ⅰ3ˉ and Ⅰ5ˉ which were confirmed by Raman spectroscopic measurement, were about twice larger than that of I-. The optimized photoenergy conversion efficiency of dye-sensitized solar cells （DSSC） with the quasi-solid-state electrolyte was 4.3% under AM 1.5 irradiation at 75 mW·cm^-2 light intensity.     

嘌呤衍生物在葫芦［6］脲单轮烷键合固定相上的色谱行为

在反相和正相色谱模式下,研究了几种嘌呤衍生物在葫芦［6］脲单轮烷键合硅胶固定相上的高效液相色谱行为,并在反相模式下与ODS固定相进行了比较,考察了流动相中甲醇含量、流动相pH值和离子强度对嘌呤化合物保留的影响。研究结果表明:在反相模式下,嘌呤化合物与葫芦［6］脲单轮烷键合相之间存在多种相互作用,除疏水作用外,分离过程中还存在与ODS不同的色谱分离机制。在正相条件下,多作用力的色谱分离机制同样存在。葫芦［6］脲单轮烷键合相与溶质之间存在疏水、氢键、π-π和偶极-偶极等多种作用力,协同作用提高了固定相对嘌呤化合物的分离选择性。     

CHEMOTHERAPEUTIC POLYMERS Ⅻ. SYNTHESIS AND ANTITUMOR ACTIVITY OF POLYAMIDES CONTAINING 5-FLUOROURACILS AS PENDANT GROUP

Six polyamides with pendant 5-fluorouracil group were synthesized by the polycondensation ofdi-p-nitrophenyl N-(5-fluorouracil-1-acetyl)glutamate with a series of polymethylene diamines.All of the new polyamides obtained are soluble in water. Their chemical structures were confirmedby ~1H NMR, UV and IR spectra as well as elemental analyses. The antitumor activity of some ofthese polyamides were tested against Ehrlich Ascites Carcinoma in mice, III_a showed an inhibitionrate of 43%.     

一种相位开关型分频器电路的噪声分析

介绍了一种相位开关型分频器电路的噪声分析方法。这种方法基于频率综合器的频域模型,能比较准确地预测分频器的相位噪声和它对整个频率综合器相位噪声的影响。分频器电路采用0.18μm CM O S工艺设计,用于W CDM A通讯系统中。在分析过程中,针对此电路的相位开关结构,提出了一些改进其噪声性能的方法。最后用仿真结果进行分析验证,仿真结果和理论相符合。     

超长PN码的延迟–等待直接捕获方法

提出了一种新的直序扩频体制卫星导航定位系统中超长PN码序列的快速直接捕获方法，即通过估计本地与卫星时间偏差来确定延迟时间，从而预置本地伪码的“延迟一等待”捕获法。文章深入分析了该方案实现的主要技术细节和捕获性能。     

腔长失调对光腔衰荡法测量精度的影响

 只考虑腔长失调因素下建立了反射率模拟测量的理论模型。根据高斯光束传输规律分析了腔长失调对衰荡腔模式耦合的影响，推导了腔长失调与谐振腔输出脉冲信号、衰荡信号与反射率之间的关系，模拟了腔长失调在±10mm范围内的光脉冲衰荡现象。结果表明：对于光敏面直径为0.2mm的高速探测器，为了保证10^-6的测量精度，腔长的失调量应控制在±1mm之间。在光路调节中采用具有对数变换功能的示波器和动态范围较大的探测器，可以提高测量精度。     

1.3μm高增益偏振无关应变量子阱半导体光放大器

采用低压金属有机化学气相外延法 (LP MOVPE)生长并制作了 1 3μm脊型波导结构偏振无关半导体光放大器 (SOA) ,有源区为基于四个压应变量子阱和三个张应变量子阱交替生长的混合应变量子阱 (4C3T)结构 ,压应变阱宽为 6nm ,应变量 1 0 % ,张应变阱宽为 11nm ,应变量 - 0 95 % ;器件制作成 7°斜腔结构以有效抑制腔面反射。半导体光放大器腔面蒸镀Ti3 O5/Al2 O3 减反 (AR)膜以进一步降低腔面剩余反射率至 3× 10 -4以下 ;在 2 0 0mA驱动电流下 ,光放大器放大的自发辐射 (ASE)谱的 3dB带宽大于 5 0nm ,光谱波动小于 0 4dB ,半导体光放大器管芯的小信号增益近 30dB ,在 12 80～ 1340nm波长范围内偏振灵敏度小于 0 6dB ,饱和输出功率大于 10dBm ,噪声指数 (NF)为 7 5dB。     

A three-dimensional in vitro culture model for primary neonatal rat ventricular myocytes

To overcome bad prognosis of patients with heart failure and the lack of organ donors, cardiac tissue engineering has developed as a biomimetic approach to repair, replace, and regenerate the damaged cardiac tissue. During the past decade years, researchers are devoted to find different natural and/or synthetic materials that can build appropriate physical structures to contain and organize implanted cells. In this study, we present a new method for primary neonatal rat cardiomyocytes culture in vitro using alginate/collagen/chitosan hydrogel. To investigate the feasibility of this material as scaffold for cardiac myocytes, neonatal rat ventricular myocytes were isolated and encapsulated in alginate-based beads cross-linked with calcium ion. The growth of cells was evaluated by staining with α-Sarcomeric actin (α-SCA) and Troponin T type 2 (TNNT2), and the viability of cardiomyocytes was studied in vitro by assessing the expression levels of several cardiac ion channels, including CACNL1A1, Connexin 43 and SCN5A. The results showed a significant increase in cardiac myocytes number, and the expression levels of CACNL1A1, Connexin 43 (Cx43) were up-regulated significantly except SCN5A, as compared with two-dimensional cultures. Moreover, extracellular matrix produced by the seeded cells themselves was observed by staining with fibronectin. Taken together, these findings indicate that this alginate/collagen/chitosan hydrogel bead is suitable for supporting the growth and retaining the morphologic and electrophysiologic characteristics of primary cultured rat cardiac muscle cells.     

Ni/TPC催化剂的制备、表征及在秸秆热解燃气重整中的应用

以废弃汽车外轮胎热解后的副产物轮胎热解焦（Tyre pyrolysis char，TPC）为原料，利用均匀沉淀法制备以轮胎焦为载体的负载型Ni/TPC催化剂，采用EDX、SEM、XRD、TG、BET手段对催化剂进行了表征与分析，同时使用管式炉测试了Ni/TPC催化剂在秸秆热解燃气重整中的催化性能，并考察了热解温度、保温时间、镍负载量及催化时间对秸秆热解燃气重整效果的影响。研究结果表明，TPC富含焦和金属，Ni/TPC催化剂分散均匀，热稳定性好，比表面积为62 m²/g。催化剂活性测试显示，Ni/TPC催化剂用于作物秸秆热解燃气重整具有很强的催化活性，可显著提高燃气中可燃气体含量；热解温度在750℃、保温时间10 min、30%的Ni负载量时Ni/TPC催化剂的催化效率最高，连续使用850 min后，燃气中的H₂含量仍相对提高到50%以上，长时间使用后活性结构由Ni₃ZnC_0.7转变成FeNi₃，催化活性依然较强且趋于稳定，TPC可以作为良好的新型镍基催化剂载体。