基于结团絮凝方式的北方地区河道底泥生态清淤技术试验探讨

在不影响生态环境的前提下,如何对河道底泥进行生态处理,一直是当前国内外研究的重要课题.文章采用结团絮凝方式,对河道底泥生态清淤方式进行试验研究.试验表明:结团絮凝药剂投放量控制在2.9％～5.1％之间,底泥生态清淤效果显著.底泥的污泥比阻和其含水率呈现负相关变化,结团絮凝方式适合于中小河流河道底泥的生态清淤应用.     

基于数据挖掘和本体的入侵警报关联模型

为了突破入侵检测领域的原有瓶颈,提出了一种新的基于数据挖掘和本体的入侵警报关联模型。该模型通过对底层警报的聚类和分类,发现并且筛选攻击,然后根据已建立的基于本体的攻击知识模型,对这些攻击进行关联,以达到识别、跟踪和预测多步攻击的目的。通过对KDD Cup1999和DARPA 2000数据集的模拟实验,验证了模型的有效性。     

A DC-Type Hybrid Step Motor for Large Power Applications

The design, construction, and operation of experimental models of a dc-type hybrid step motor are discussed. This form of hybrid motor consists of a variable-reluctance step motor, the rotor of which is appropriately wound as a multipole dc motor. A computer-aided design procedure is discussed that is used to obtain the optimum parameters of the dc portion of the hybrid motor. The results obtained with two experimental models of this type of hybrid motor are presented. Both prototypes show a marked improvement in the running torque characteristics due to the dc windings. Torque-speed curves indicate load torques of 400 oz-in available at speeds up to several thousand revolutions per minute with one of the proto-types. This type of hybrid motor may be controlled in one of three different ways: a pure step motor, a pure dc motor, or a dc-aided step motor. The relative advantages, disadvantages, and application of each control mode are discussed. Several control strategies-open and closed loop-are presented for speed control as well as point-to-point type control of position. The practical feedback feasibility of this concept for high-power applications in the integral horsepower range is discussed.     

Masson's "vegetant intravascular hemangioendothelioma:" a lesion often mistaken for angiosarcoma: study of seventeen cases located in the skin and soft tissues

The occurrence of Masson's "hemangio-endotheliome vegetant intravasculaire" (Masson's pseudoangiosarcoma) in the skin and soft tissues is illustrated with 17 surgically excised specimens. Two forms are recognized; it may appear either as a pure lesion or as a focal condition in a pre-existing vascular process, such as pyogenic granuloma or hemangioma. The clinical appearance is not specific and the diagnosis can only be established by microscopic examination. It shows a predilection for the head and extremities. Its characteristic morphologic appearance makes possible its differentiation from a group of benign and malignant vascular proliferations. The key microscopic feature is the presence of a papillary growth composed of hyperplastic endothelial cells supported by delicate fibrous stalks entirely confined within the vascular lumen. The lesion should not be mistaken for angiosarcoma, since its clinical behavior is invariably benign.     

Fluorescence from fluorescent dye based polyurethane ionomer(III)

A series of reactive fluorescent dyes were successfully synthesized and their structure was proven by IR spectra, NMR spectra, elemental analysis, and mass spectra. The fluorescence performance 6‐amino‐2(‐3‐phenyl‐propyl)‐benzo[de]isoquinoline‐1,3‐dione and 2‐benzyl‐6‐hydroxy‐benzo[de]isoquinoline‐1,3‐dione appears at around 276 and 437.4 nm, respectively, and their quantum yields are 0.662 and 0.562, respectively. It is important to indicate that the fluorescence performance is better for 6‐amino‐2(‐3‐phenyl‐propyl)‐benzo[de]isoquinoline‐1,3‐dione than for as a result of more electron donating groups linked to the 6‐amino‐2(‐3‐phenyl‐propyl)‐benzo[de]isoquinoline‐1,3‐dione molecule. These fluorescent dyes further react with toluene diisocyanate and other additives to form fluorescent dye based polyurethane (PU) ionomer molecules, and their structures are demonstracted by IR spectra. In aqueous solution, the fluorescence performance appears to be better for 6‐amino‐2(‐3‐phenyl‐propyl)‐benzo[de]isoquinoline‐1,3‐dione based PU ionomer than for 6‐amino‐2‐phenyl‐ethyl‐benzo[de]isoquinoline‐1,3‐dione based PU ionomer. For the fluorescent dye based PU ionomer molecule system, the number‐average particle sizes of the fluorescent dye based PU ionomer molecules in water increase with increasing concentration of the fluorescent dye, as a result of the increased free volume of the ionomer molecule. This may be the result of increased intermolecular interactions between ionomer– molecules themselves. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 455–465, 2005     

3D printing robot: model optimization and image compensation

A novel 7-axis robot for industrial large 3D printing applications is presented in this paper,which is developed by Institute of Robotics and Automatic Information System,Nankai University.Base on the prototype,the mechanism on three-dimensional printing is deeply dissected.By investigating the reason of color distortions in 3D printing, a novel multistep compensation algorithm based on model optimization and image compensation is developed.Finally,the experimental results show the performance of the 3D printing robot platform and the proposed algorithms.     

抗氧剂二硬脂基季戊四醇二亚磷酸酯的合成新工艺

本文以季戊四醇、亚磷酸三乙酯和十八醇为原料，在实验室合成了二硬脂基季戊四醇二亚磷酸酯。考查了反应温度、反应时间、催化剂及物料配比对产品收率的影响．实验结果表明，整个工艺过程可分为两步：合成季戊四醇二亚磷酸酯中间体时，最佳的工艺条件为：亚磷酸三乙酯、季戊四醇的摩尔比为2．05：1，催化剂的用量为季戊四醇量的3％，反应温度为13℃，时间为2．5h；在二硬脂基季戊四醇二亚磷酸酯的合成时，十八醇与中间体季戊四醇二亚磷酸酯的摩尔比为2．05：1，反应温度为16℃，时间3h。合成的产品中无酚无三废产生，产品元素分析及红外光谱与目的产物相一致。     

Tacticity effects on the miscibility behavior of poly(methyl methacrylate)/poly(ethylene oxide-b-dimethylsiloxane-b-ethylene oxide) blends

The miscibility of a triblock copolymer poly(ethylene oxide)-poly(dimethylsiloxane)-poly(ethylene oxide) with syndiotactic and isotactic poly(methylmethacrylate) wasstudied. Although isotactic poly(methyl methacrylate) (PMMA) was miscible with poly(ethylene oxide) (PEO) in the pure state, it was immiscible with the PEO end blocks in the copolymer. In comparison, the syndiotactic poly(methyl methacrylate) (sPMMA) was miscible with the PEO blocks as indicated by melting point depression, decrease in crystallinity, and slower rate of spherulite growth of PEO. When blends of the triblock copolymer were cooled to low temperatures, the poly(dimethylsiloxane) (PDMS) middle block which resided in the interlamellar region of PEO spherulites also crystallized; the development of PDMS crystals was clearly suppressed at high sPMMA contents.On leave from Union Chemical Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan     

Aluminum Silicate Films Obtained by Low-Pressure Metal-Organic Chemical Vapor Deposition

Amorphous alumina-silica films with film thickness of 0.41–2.69 μm were prepared on glass and silicon substrates by metal-organic chemical vapor deposition using a mixture of aluminum tri-sec-butoxide (ATSB), hexamethyldisilazane (HMDSN), and argon. By controlling the inputs of ATSB and HMDSN, alumina-silica thin films could contain varied compositions and adjustable properties. Basically, the codeposition of alumina and silica to form alumina-silica using ATSB and HMDSN had a faster growth rate than their individual components. The internal stress could be adjusted by deposition temperature and reactant inputs. Adhesion could be improved by having a silicon-rich thin film, whereas an aluminum-rich film could have slightly higher hardness. Optical properties, e.g., refractive index and optical transmittance, were also measured.