N-苄基丙烯酰胺的合成

以丙烯腈和苯甲醇为原料，浓硫酸作催化剂，合成了N-苄基丙烯酰胺（N-BAA）。考察了反应温度、反应时间和催化剂用量等因素对产物收率的影响，得出了最佳反应条件：n（丙烯腈）：n（苯甲醇）：n（浓硫酸）=3：1：1．2，反应时间3h，反应温度60℃。在最佳条件下，N-BAA的收率可达92％。每100g粗产物用10％氢氧化钠溶液提纯，精制产物纯度可达99．80％，熔点为64～65℃。通过红外光谱对产物结构进行了表征。     

过钻头测井技术——一种新的测井数据采集方式毕

过钻头测井技术是一种新的测井数据采集方式，被评为2005年国际石油科技十大进展之一。介绍了过钻头测井技术的工作原理和实例，分析了过钻头测井技术的优点。通过电缆测井和随钻测井对比的分析，认为过钻头测井不仅会成为水平井、大斜度井及困难井眼条件首选测量方式，也会逐渐在直井中推广普及。     

齐鲁PE100级燃气管专用料的研制

对齐鲁PE100级燃气管专用料DGDB2480HBK的力学性能、耐慢速裂纹增长性能、熔体强度等进行了研究与分析。结果表明,DGDB2480HBK的耐慢速裂纹增长性能在500h以上;熔体强度在1.0MPa以上;200℃氧化诱导期在65min左右;具有良好的加工性能,专用料的性能完全满足国内生产燃气管的要求。     

900℃空气退火对L-MBE生长的ZnO薄膜发光特性的影响

采用激光分子束外延法在蓝宝石衬底(0001)上生长了高度c轴择优取向的高质量ZnO薄膜,在空气中对生长的薄膜进行900℃退火处理,并对退火前后样品的结晶质量、发光特性采用X射线衍射(XRD)、变温光致发光(PL)研究.退火处理后的ZnO薄膜(0002)面XRDθ-2θ扫描曲线强度明显增强.在光致发光实验中,观测到薄膜分别在3.352,3.309和3.237eV附近有3个明显的近紫外发光峰,分别对应自由激子发射、中性施主或受主束缚激子I9及其声子伴线1Lo.随着温度升高,峰位逐渐向长波方向移动(即所谓"红移"),半高宽(FWHM)逐渐展宽;在发光谱中,来自于晶体缺陷的深能级(DL)区发光强度极小.     

Fluorinated and Alkylthiolated Polymeric Donors Enable both Efficient Fullerene and Nonfullerene Polymer Solar Cells

In this work, four donor (D)–acceptor (A) copolymers based on benzodithiophene (BDT) and benzothiadiazole (BT) with different alkylthiolated and/or fluorinated side chains are developed for efficient fullerene and nonfullerene polymer solar cells (PSCs). The synergistic effect of sulfuration and fluorination on the optical absorption, energy level, crystallinity, carrier mobility, blend morphology, and photovoltaic performance is investigated systematically. By incorporating sulfur atoms onto the side chains, a little blueshifted but significantly increased absorption can be obtained for PBDTS‐FBT compared to PBDT‐FBT . On the other side, a little more blueshifted but much stronger absorption and much lower‐lying highest occupied molecular orbital (HOMO) level can be realized for PBDTF‐FBT when introducing fluorine atoms instead of sulfur atoms. With the combination of both fluorination and sulfuration strategies, PBDTS‐FBT exhibits the best absorption ability, lowest HOMO energy level, and highest crystallinity, which make PBDTSF‐FBT devices show the highest power conversion efficiency (PCE) of 10.69% in fullerene PSCs and 11.66% in nonfullerene PSCs. The PCE of 11.66% is the best value for PSCs based on BT‐containing copolymer donors reported so far. The results indicate that fluorination and sulfuration have a synergistically positive effect on the performance of D–A photovoltaic copolymers and their solar cell devices.     

一种低温漂CMOS带隙基准电压源的设计

阐述了一种采用了一阶温度补偿技术设计的CMOS带隙基准电压源电路。该电路采用Chartered0.25 μm N阱CMOS工艺实现。基于HSPICE的仿真结果表明:当温度在-25℃到85℃之间变化时该电路输出电压的温度系数为12.10~(-6)/℃、。在3.3 V电源电压下的功耗为3.8 mW,属于低温漂、低功耗的基准电压源。     

刚玉流动粒子炉过饱和渗碳工艺的研究

采用上海新跃仪表厂自行研制的刚玉流动粒子炉对三种新型模具钢进行了过饱和渗碳工艺的研究。结果表明:适当控制氮气与丙烷的比例可以获得良好的渗层组织及很高的表面硬度;刚玉流动粒子炉渗碳能够获得较高的渗碳速度。     

DCT algorithms for composite sequence lengths

This paper presents fast algorithms for the type-II and -III discrete cosine transforms of composite sequence length. In particular, a radix-q algorithm, where q is an odd integer, is derived for uniform or mixed radix decomposition of the discrete cosine transform. By combining the radix-q and radix-2 algorithms, a general decomposition method for any composite length is developed. Reduction of computational complexity can be achieved for many sequence lengths compared with that needed by the well-known radix-2 algorithm. Furthermore, both the proposed and Chan and Siu's (1993) mixed radix algorithms achieve the same computational complexity for N=3*2^p and 9*2^P. However, our algorithm uses a simpler decomposition approach and provides a wider range of choices of sequence lengths     

Computation of 2D discrete Hartley transform

Based on a decimation-in-time decomposition, a fast split-radix algorithm for the 2D discrete Hartley transform is presented. Compared to other reported algorithms, the proposed algorithm achieves substantial savings on the number of operations and provides a wider choice of transform sizes