Solubility and Crystallization of Piroxicam from Different Solvents in Evaporative and Cooling Crystallization

In this work, the solubility of a non-steroidal anti-inflammatory drug (NSAID), piroxicam, is investigated. The polymorphic form II, which is the most stable form at room temperature, was investigated in seven different solvents with various polarities. It has been found that the solubility of piroxicam in the solvents is in the following order: chloroform > dichloromethane > acetone > ethyl acetate > acetonitrile > acetic acid > methanol > hexane. Crystallization of piroxicam from different solvents has been performed with evaporative crystallization and cooling crystallization; the effects of solvent evaporation rate and solute concentration have also been studied. Both form I and form II could be produced in cooling and evaporative crystallization, and no simple link can be identified between the operating parameters and the polymorphic outcome. Results obtained in the present work showed the stochastic nature of the nucleation of different polymorphs as well as the complexity of the crystallization of a polymorphic system.

UCrawler: A learning-based web crawler using a URL knowledge base

Focused crawlers, as fundamental components of vertical search engines, focus on crawling the web pages related to a specific topic. Existing focused crawlers commonly suffer from the problems of low efficiency of crawling pages and subject migration. In this paper, we propose a learning-based focused crawler using a URL knowledge base. To improve the accuracy of similarity, the similarity of the topic is measured with the parent page content, anchor information, and URL content. The URL content is also learned and updated iteratively and continuously. Within the crawler, we implement a crawling mechanism based on a combination of content analysis and simple link analysis crawler strategy, which decreases computational complexity and avoids the locality problem of crawling. Experimental results show that our proposed algorithm achieves a better precision than traditional methods including the shark-search and best-first search algorithms, and avoids the local optimum problem of crawling.

Bicrystallography and Beyond: Example of Group–Subgroup Phase Transformations

This paper presents the basic elementary tools for describing the global symmetry obtained by overlapping two or more crystal variants of the same structure, differently oriented and displaced one with respect to the other. It gives an explicit simple link between the concepts used in the symmetry studies on grain boundaries on one side and group–subgroup transformations on the other side. These questions are essentially of the same nature and boil down to the resolution of the same problem: identifying the permutation groups that are images of the corresponding applications. Examples are given from both domains, classical grain boundaries with coincidence lattices and group–subgroup phase transformations that illustrate the profound similarities between the two approaches.

Pic Microcontroller Based Automatic Stamping Machine

This paper proposes the design of PIC Microcontroller based Automatic Stamping machine. In stamping industry & printing industry stamping machine is one of the standard machines. It is mainly used to trample the emblem or any other secret code. This automatic Stamping machine is useful in academic institutions, administration offices, Post offices, finance department etc. A roller mechanism is used for the feed of the paper and the stamping will be done by including a simple link mechanism. The structure can easily be simplified by using crank shaft and screw rod mechanism.

On a Simple Relation between Duffin-Kemmer-Petiau and Tzou Algebras

A simple link between βμ matrices of the Duffin-Kemmer-Petiau theory and ρμ matrices of Tzou representations is constructed. The link consists of a constant unitary transformation of the βμ matrices and a projection onto a lower-dimensional subspace.

Prediction of missing links and reconstruction of complex networks

Predicting missing links in complex networks is of great significance from both theoretical and practical point of view, which not only helps us understand the evolution of real systems but also relates to many applications in social, biological and online systems. In this paper, we study the features of different simple link prediction methods, revealing that they may lead to the distortion of networks’ structural and dynamical properties. Moreover, we find that high prediction accuracy is not definitely corresponding to a high performance in preserving the network properties when using link prediction methods to reconstruct networks. Our work highlights the importance of considering the feedback effect of the link prediction methods on network properties when designing the algorithms.