Agilent Technologies

About: Agilent Technologies is a company organization based out in Santa Clara, California, United States. It is known for research contribution in the topics: Signal & Mass spectrometry. The organization has 7398 authors who have published 11518 publications receiving 262410 citations. The organization is also known as: Agilent Technologies, Inc..

Perspectives on recent advances in the speed of high-performance liquid chromatography.

Abstract: Perhaps the most consistent trend in the development of high-performance liquid chromatography (HPLC) since its inception in the 1960s has been the continuing reach for ever faster analyses. The pioneering work of Knox, Horvath, Halasz, and Guiochon set forth a theoretical framework that was used early on to improve the speed of HPLC, primarily through the commercialization of smaller and smaller particles. Over the past decade, approaches to improving the speed of HPLC have become more diverse, and now practitioners of HPLC are faced with the difficult task of deciding which of these approaches will lead them to the fastest analysis for their application. Digesting the rich literature on the optimization of HPLC is a difficult task in itself, which is further complicated by contradictory marketing messages from competing commercial outlets for HPLC technology. In this perspectives article we provide an overview of the theoretical and practical aspects of the principal modern approaches to improving the speed of HPLC. We present a straightforward theoretical basis, informed by decades of literature on the problem of optimization, that is useful for comparing different technologies for improving the speed of HPLC. Through mindful optimization of conditions, high-performance separations on the subminute timescale are now possible and becoming increasingly common under both isocratic and gradient elution conditions. Certainly the continued development of ultrafast separations will play an important role in the development of two-dimensional HPLC separations. Despite the relatively long history of HPLC as an analytical technique, there is no sign of a slow-down in the development of novel HPLC technologies.

Imaged document text retrieval without OCR

Abstract: We propose a method for text retrieval from document images without the use of OCR. Documents are segmented into character objects. Image features, namely the vertical traverse density (VTD) and horizontal traverse density (HTD), are extracted. An n-gram-based document vector is constructed for each document based on these features. Text similarity between documents is then measured by calculating the dot product of the document vectors. Testing with seven corpora of imaged textual documents in English and Chinese as well as images from the UW1 (University of Washington 1) database confirms the validity of the proposed method.

Distributed Asynchronous Collections: Abstractions for Publish/Subscribe Interaction

Abstract: Publish/subscribe is considered one of the most important interaction styles for the explosive market of enterprise application integration. Producers publish information on a software bus and consumers subscribe to the information they want to receive from that bus. The decoupling nature of the interaction between the publishers and the subscribers is not only important for enterprise computing products but also for many emerging e-commerce and telecommunication applications. It is often claimed that object-orientation is inherently incompatible with the publish/subscribe interaction style. This flawed argument is due to the persistent confusion between object-orientation as a modeling discipline and the specific request/reply mechanism promoted by CORBA-like middleware systems. This paper describes object-oriented abstractions for publish/subscribe interaction in the form of Distributed Asynchronous Collections (DACs). DACs are general enough to capture the commonalities of various publish/subscribe interaction styles, and flexible enough to allow the exploitation of the differences between these flavors.

Resonant Crossover of Terahertz Loss to the Gain of a Bloch Oscillating InAs=AlSb Superlattice

Abstract: Terahertz absorption in waveguides loaded with InAs/AlSb super-superlattice mesas reveals a frequency dependent crossover from loss to gain that is related to the Stark ladder produced by an applied dc electric field. Electric field domains appear to be suppressed in the super-superlattice composed of many very short segments of superlattice, interrupted by heavily doped InAs regions. Resonant crossover is indicated by an increase in terahertz transmission as the Stark splitting or Bloch frequency determined by the applied dc electric field exceeds the measurement frequency.

Method for the simultaneous formation of via-holes and wraparound plating on semiconductor chips

Abstract: Metallized via-holes and a wraparound metal plating are simultaneously formed on semiconductor chips by patterning a photoresist mask on the front surface of the wafer to open windows over metal pads as well as the grid areas where wraparound plating is desired; etching off the exposed metal if necessary and forming via-holes and grooves in the wafer by reactive ion etching to a depth which is less than the total thickness of the wafer; depositing a thin conductive film along the walls of the grooves and via-holes by electroless methods; plating the walls of the grooves and the via-holes with conductive metal by electrolytic methods; removing the back surface of the wafer ("backlapping") along with the floors of both the grooves and the via-holes, to expose the metal on the wall of the via-holes and separate the individual chips; and, depositing conductive metal on the back surface of the individual chips to complete the grounding path.