利用菜籽油脱臭馏出物制备生物柴油新工艺

以菜籽油脱臭馏出物为原料,首先以D002阳离子交换树脂作催化剂,进行酯化反应,降低原料酸值;然后以氢氧化钾作催化剂进行醇解反应来制备生物柴油的二步法新工艺路线。结果表明:D002阳离子交换树脂具有很强的催化活性,游离脂肪酸最高转化率达97.7%,连续使用4次后,催化活性仍然很高,达96%以上;碱催化过程中甘油酯的最高转化率达97.4%。产品品质大都符合美国ASTMD6751-03生物柴油标准。由此可见,先用树脂催化处理高酸值废油,然后进行碱催化制备生物柴油二步法工艺是一种切实可行的方法。     

基于C8051F002的微处理器温度补偿石英晶体振荡器

文中利用新型的芯片，采用曲线拟合、实验标定等方法构成的微处理器温度补偿石英晶体振荡器，与以往的微处理器温度补偿晶体振荡器相比，体积更小、频率的稳定度和准确度更高。     

10%SIOC-I-002水乳剂配方研究

对新化合物SIOC-I-002进行水乳剂配方筛选研究。通过对溶剂、乳化剂、增稠剂等相关助剂的筛选,确定最优配方为SIOC-I-002有效成分≥10%、二甲苯8%、YUS-D9356%、SFR-T3%、乙二醇4%、水补足至100%;进一步对两种加工工艺进行比较,结果表明直接乳化法制得的制剂更优于转相法所得的制剂。对最佳配方进行重复性实验,结果表明研究所得10%SIOC-I-002水乳剂筛选配方具有物理稳定性好、有效成分含量稳定、流动性好等特点,且加工工艺简单。     

Sample-weighted clustering methods

Although there have been many researches on cluster analysis considering feature (or variable) weights, little effort has been made regarding sample weights in clustering. In practice, not every sample in a data set has the same importance in cluster analysis. Therefore, it is interesting to obtain the proper sample weights for clustering a data set. In this paper, we consider a probability distribution over a data set to represent its sample weights. We then apply the maximum entropy principle to automatically compute these sample weights for clustering. Such method can generate the sample-weighted versions of most clustering algorithms, such as k-means, fuzzy c-means (FCM) and expectation & maximization (EM), etc. The proposed sample-weighted clustering algorithms will be robust for data sets with noise and outliers. Furthermore, we also analyze the convergence properties of the proposed algorithms. This study also uses some numerical data and real data sets for demonstration and comparison. Experimental results and comparisons actually demonstrate that the proposed sample-weighted clustering algorithms are effective and robust clustering methods.     

Al薄膜对(002)ZnO/Al/Si结构基片中ZnO薄膜特性影响的实验研究

采用射频磁控溅射法沉积制备了(002)ZnO/A l/Si复合结构。研究了Al薄膜对(002) ZnO/Al/Si复合结构的声表面波器件(SAWD)基片性能影响以及当ZnO 薄膜厚度一定时的Al膜最佳厚度。采用X射线衍射(XRD)对Al和ZnO薄膜进行了结构表征 ,采用 扫描电镜(SEM)对ZnO薄膜进行表面形貌表征,并从薄膜生长机理角度进行了分析。结果 表明,加Al薄膜有利于ZnO薄膜按(002)择优取向生长,并且ZnO 薄膜的结晶性能提高;与(002)ZnO/Si结构基片相比,当Al薄膜 厚为100nm时,(002)ZnO/Al/Si结构中ZnO薄 膜的机电耦合系数提高 了65%。     

Survey of microwave surface impedance data of high-Tc superconductors—Evidence for nonpairing charge carriers

The microwave surface impedance of the high-T _c oxide superconductors has been measured at many laboratories around the world. A survey of their data between 100 MHz and 150 GHz for polycrystalline as well as single crystalline samples is given, focusing on YBa₂Cu₃O_7– . In comparison to the classical superconductors, these results reveal a very similar temperature dependence of the surface impedance close toT _c but an anomalous high residual surface resistance at lower temperatures. Both features can be explained by the assumption that oxide superconductors contain a significant number of nonpairing charge carriers. Within the framework of a properly extended two-fluid model, this is shown by analysis of our best thin-film data. Moreover, the enhanced losses in polycrystalline material especially for superposed magnetostatic fields result, to a large extent, from the deeper penetration depth. The possible origin of the nonpairing charge carriers and their impact on the applicability of the oxide superconductors is briefly discussed.     

LC-MS/MS快速测定大鼠血浆中HHY-002浓度

目的: 建立用于测定治疗慢性心律失常药物HHY-002的大鼠血浆测定法。方法: 流动相为乙腈-0.1%甲酸(65∶35),流速 0.200 mL/min,色谱柱Phenomenex Luna C₁₈柱(150 mm×2.00 mm,5 μm,5 micron),进样量为 10 μL,柱温 35 ℃,以地西泮为内标。结果: HHY-002在 1.98~1013.50 ng/mL 的范围内呈良好的线性关系(r=0.998),最低定量限达 1.98 ng/mL,绝对回收率高于80%,日内和日间误差小于10%,方法回收率大于(81.4±4.5)%,符合生物样品分析要求。结论: 建立的LC-MS/MS方法专属性强,灵敏度高,可用于HHY-002的体内定量分析。     

川阿格雷钠舒张血管的作用及机制研究

目的 研究川阿格雷钠(MC-002)对大鼠胸主动脉的舒张作用,并探讨其可能的作用机制。方法 测定川阿格雷钠对去甲肾上腺素(NE)和高钾预收缩的大鼠胸主动脉血管环的舒张作用,并观察L-硝基精氨酸甲酯(L-NAME)、亚甲蓝、吲哚美辛、格列本脲、蜂毒明肽、氯化钡和4-氨基吡啶对其作用的影响。结果 川阿格雷钠(3~300 μmol/L)能浓度依赖性地舒张NE预收缩的完整血管环,去内皮、亚甲蓝孵育和吲哚美辛孵育均能显著抑制其舒血管作用(P<0.05,P<0.01),L-NAME孵育无显著影响。川阿格雷钠拮抗高钾诱导完整血管环收缩的作用被格列本脲(ATP敏感型钾通道KATP抑制剂)和蜂毒明肽(小传导性钙激活型钾通道SKCa抑制剂)显著降低(P<0.01),氯化钡和4-氨基吡啶无显著影响。川阿格雷钠使NE预收缩的血管平滑肌的钙浓度-收缩曲线下移、右移,且呈现浓度依赖性。结论 川阿格雷钠可能通过内皮细胞的鸟苷酸环化酶途径和环氧合酶途径、开放KATP和SKCa引起平滑肌细胞膜超极化以及减少钙内流而松弛血管。     

广安002号区块综合治漏技术

从井身结构、造斜点选择、钻井液性能、堵漏方式和技术措施上进行了分析研究,提出了一套适合广安002号区块的综合治漏技术,给出了小漏（0～5m3／h）、中漏（5～30m3,h）和大漏（30m3／h～失返）的推荐堵漏方案。通过对广安002-H1-2、广安002-H9、广安002-X28等井现场应用的分析,发现该种综合治漏技术取得了明显的效果,减少了因井漏造成的垮塌、卡钻、形成新井眼等事故,缩短了钻井周期,降低了钻井成本。