A Study on NMR and GC/MS Spectra of the Isomers of Linear Hexyl Naphthalene

The GC/MS and NMR analysis of the reaction products of naphthalene with 1-bromohexane were reported. The products obtained were suggested to have six isomers of linear hexylnaphthalene and the structure of each isomer was determined by GC/MS and NMR spectra. For the first time, the unique chemical shift data were obtained. The content of each isomer calculated by ¹H NMR and ¹³C NMR spectra was consistent with that by GC/MS spectra, which confirmed the accuracy of NMR data.     

行波管放大器相位噪声的分析及其抑制

主要分析规则调相信号对行波管放大器频谱纯度的影响,并且根据行波管放大器相位噪声产生的过程和原因,提出两种抑制相位噪声的方法.     

Softwarekartographie

Zusammenfassung  Anwendungslandschaften in Unternehmen sind langlebige hoch-komplexe Strukturen bestehend aus hunderten bis tausenden von miteinander vernetzten betrieblichen Informationssystemen, die von Personen mit sehr unterschiedlichen Interessen und Erfahrungshintergrund konzipiert, erstellt, modifiziert, betrieben, genutzt und finanziert werden. Die Softwarekartographie zielt darauf ab, die Kommunikation zwischen diesen Personen durch zielgruppenspezifische verst?ndliche graphische Visualisierungen zu unterstützen, die Gesch?fts- und Informatik-Aspekte gleicherma?en berücksichtigen, und die speziell für langfristige und strategische Management-Betrachtungen geeignet sind. In diesem Beitrag fassen wir zun?chst die in der betrieblichen Praxis wohlbekannten Probleme beim Management von Anwendungslandschaften zusammen und diagnostizieren erhebliche Kommunikationsdefizite. Da Anwendungslandschaften als Systeme von Systemen mit Menschen als integrale Systembestandteile zu verstehen sind, werden Karten als attraktiver L?sungsansatz identifiziert und die wesentlichen Konzepte der Softwarekartographie anhand von Beispielen vorgestellt. Dabei werden Querbezüge zu anderen Fachgebieten der Informatik und Wirtschaftsinformatik hergestellt, und die bisherige Nutzung der Forschungsergebnisse in der Praxis gezeigt.     

Investigation of Mechanical and Electrical Characteristics for Cracked Conductive Particle in Anisotropic Conductive Adhesive (ACA) Assembly

In an anisotropic conductive adhesive (ACA) assembly, the electrical conduction is usually achieved with the conductive particles between the bumps of integrated circuit (IC) and corresponding conductive tracks on the glass substrate. Fully understanding of the mechanical and electrical characteristics of ACA particles can help to optimize the assembly process and improve the reliability of ACA interconnection. Most conductive particles used in the ACA assembly are with cracks in the metal coating of the particles after the ACA bonding. This paper introduced the fracture analysis by applying the cohesive elements in the numerical model of the nickel-coated polymer particle and further simulating the cracks initiation and propagation in the nickel coating during the ACA bonding. The simulation results showed that the stress distribution on the nickel-coated particle with cracks was significantly different from that on the nickel-coated particle without crack, indicating that the stress analysis by taking the crack into consideration is very important for the reliability assessment of the ACA interconnection. The stress analysis of cohesive elements indicated that the cracks initiated at the central area of the nickel coating and propagated to the polar area. Furthermore, by the introduction of a new parameter of the virtual resistance, a mathematical model was established to describe the electrical characteristics of the nickel-coated particle with cracks. The particle resistance of the nickel-coated particle with cracks was found to be much higher than that of the particle without crack in the optimized bonding pressure range, indicating that it is necessary to take the crack into consideration for the particle conduction analysis as well. Therefore, the fracture analysis on the conductive particle by taking the crack into consideration could accurately evaluate the reliability of ACA interconnection and avoid serious reliability issues.     

镁钴铝类水滑石催化合成安息香甲醚

采用共沉淀法制备了镁钴铝类水滑石化合物(MgCoAl-HTLcs),并用 X 射线衍射、扫描电子显微镜、NH_3程序升温脱附等方法对 MgCoAl-HTLcs 进行了表征,并以 MgCoAl-HTLcs 为催化剂催化苯甲醛与甲醇反应合成安息香甲醚,研究了n(Mg):n(Co):n(Al)、催化剂用量、原料配比、反应温度、反应时间对合成反应的影响。表征结果显示,MgCoAl-HTLcs 的晶相完整,表面主要为弱酸、弱碱性。催化合成安息香甲醚的适宜条件为:MgCoAl-HTLcs 催化剂用量0.10 g(约为原料总质量的0.23%),n(Mg):n(Co):n(Al)=0.4:1.6:1.0,V(苯甲醛):V(甲醇)=3:50,反应温度50℃,反应时间150 min。在此条件下,苯甲醛的平衡转化率达77.49%,安息香甲醚选择性接近100%。为洁净合成安息香甲醚开辟了一条新的途径。     

Recrystallization of phenylbutazone using supercritical fluid antisolvent process

Phenylbutazone was recrystallized from its solutions by using a supercritical fluid antisolvent process. It was dissolved in acetone and supercritical carbon dioxide was injected into the solution, thereby inducing supersaturation and particle formation. Variation in the physical properties of the recrystallized phenylbutazone was investigated as a function of the crystallizing temperature and the carbon dioxide injection rate. The recrystallized particles showed cleaner surfaces and more ordered morphology compared to the particles obtained by other methods such as solvent evaporation. X-ray diffraction patterns indicated that the crystallinity of the particles had been modified upon the recrystallization. Differential scanning calorimetry measurement revealed that the crystallizing temperature influenced the thermal stability of the resulting crystals. Larger crystals were produced when the carbon dioxide injection rate was reduced.     

从关联分析法看如何改善沥青抗老化性能

用灰色关联分析法研究了沥青抗老化性能与沥青化学组成之间的关联程度，结果表明，影响再生沥青性质的主要因素是沥青中的芳烃和胶质的含量。通过添加芳香组分能改善沥青四组分之间的配伍性，从而可以改善再生沥青的抗老化性能。并通过对再生剂进行富芳处理，验证了上述结论。     

Photochemical reduction of molecular weight and number of double bonds in natural rubber film

Natural rubber (NR) can be degraded depending on various factors such as heat, mechanical force, chemical reaction, and light. Light is a very interesting factor because it can cause the NR to degrade under low temperature and pressure. The photo-degradation of NR films was carried out to investigate the effects of the light and the temperature on the reduction of the weight-average molecular weight (Mw) and the double bonds in the NR films. The NR films, with and without catalysts, titanium dioxide (TiO₂), and potassium persulfate (K₂S₂O₈), were exposed to light from a mercury light bulb at 7,000 and 36,000 lux, and at the temperature of 25 °C and 80 °C for 192 hrs. After exposure, the Mw of the NR films was analyzed by gel permeation chromatography (GPC). Changes in the Mw were used to construct a kinetic model for the process, (1/Mw)=(1/Mw₀)+(kt/2M₀) where k is the rate constant, and M₀ is the Mw of the monomer unit. The linear relationship between 1/Mw and time suggested pseudo first-order processes with random scission. The Mw distribution information from the GPC was used to calculate the number of double bonds in the NR films. The trend of the double bonds reduction curves was quite similar to the result obtained from the calculation from the FTIR spectra. This indicated that this calculation method might possibly be another alternative way to obtain the number of double bonds in the NR.     

A novel distributed approach to robust fault detection and identification

In this paper, we propose a novel distributed robust fault detection and identification (RFDI) scheme for a class of nonlinear systems. Firstly, a detection and identification estimator—robust fault tracking approximator (RFTA) is designed for online health monitoring. A novel feature of the RFTA is that it can simultaneously detect and accurately identify the shape and magnitude of the fault and disturbance. Moreover, it takes less online training time compared with the traditional neural network based fault diagnosis schemes. For some distributed systems, a network of distributed estimators is constructed where the RFTA is embedded into each estimator. Then we use consensus filter to filter the outputs of each estimator. One of the most important merits of the consensus filter is that its outputs can dramatically improve the accuracy of fault detection and identification. Next, the stability of the distributed RFDI scheme is rigorously investigated. Finally, two numerical examples are given to illustrate the feasibility and effectiveness of the proposed approach.     

PVC树脂聚合用有机过氧化物引发剂

介绍了目前国内外引发剂的使用及开发方向,并对引发剂的选择及其对树脂质量的影响进行了讨论。