Investigation of the Equivalence of National Dew-Point Temperature Realizations in the ?50?°C to +?20?°C Range

In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4?years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from ?50?°C to +20?°C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008?°C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025?°C at ?50?°C and 0.010?°C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field.     

Bioprocess Scale-up for Acetohydroxamic Acid Production by Hyperactive Acyltransferase of Immobilized Rhodococcus Pyridinivorans

Catalysis Letters - In this study, Rhodococcus pyridinivorans cells containing hyperactive acyltransferase was immobilized on various macromolecules based-polymeric matrices and used to improve...     

Traction Energy Cost Reduction of the WMATA Metrorail System

An energy cost reduction study was conducted on the Washington Metropolitan Area Transit Authority Metrorail system. Its primary objectives were to classify primary energy end uses and identify conservation methods which have the highest potential for reducing the electric bill. The effort involved analyzing present energy costs, developing cost- effective conservation strategies, determining the savings associated with the strategies by simulation, recommending appropriate strategies for implementation and outlining a program for executing the recommendations. Although the effort involved both traction and support energy, only the traction energy aspects of the study are reported. It is the first time that the energy management model developed for the transit industry by the Rail Systems Center at Carnegie-Mellon University was comprehensively applied to a rapid transit property. The application was verified by comparing the simulated results to actual data. For anl practical purposes, the simulated results agree to within three percent of the actual energy consumption. Four traction energy conservation strategies were recommended for implementation based on high benefit and low cost. These are coasting, passenger load factor improvement, planned catch-up operation, and regeneration of braking energy. All of these strategies have payback periods of less than three years.     

Endcoding complexity versus minimum distance

A bound on the minimum distance of a binary error-correcting code is established given constraints on the computational time-space complexity of its encoder where the encoder is modeled as a branching program. The bound obtained asserts that if the encoder uses linear time and sublinear memory in the most general sense, then the minimum distance of the code cannot grow linearly with the block length when the rate is nonvanishing, that is, the minimum relative distance of the code tends to zero in such a setting. The setting is general enough to include nonserially concatenated turbo-like codes and various generalizations. Our argument is based on branching program techniques introduced by Ajtai. The case of constant-depth AND-OR circuit encoders with unbounded fanins are also considered.     

Waveform recognition in the presence of domain and amplitude noise

In this paper, we discuss the problem of recognizing single-dimensional, real-valued, functions in the presence of domain noise (i.e., noise that affects the domain rather than the amplitude). This problem is inspired by the field of on-line character recognition where it is more natural to view the hand as deforming the domain of the character rather than adding noise to its amplitude. The results obtained illustrate the difficulties one faces when dealing with both domain and amplitude deformation of waveforms or images. Our major result is a set of sufficient conditions that a recognition metric has to satisfy. Examples of metrics that satisfy these conditions, and hence are appropriate for recognition when the deformation affects the domain rather than the amplitude, include the supnorm metric and the total variation metric. Furthermore, we extend the results to the case when a waveform is corrupted by both amplitude and domain deformation     

Study of Band Structure Properties of Pnictide LaO1−xF x FeAs (x = 0, 0.2) Superconducting Compound

This paper reports on the band structure properties and changes in band structure of fluorine-doped LaO_1?x F _x FeAs (x = 0, 0.2) compound, measured using X-ray photoemission spectroscopy (XPS). The band structure of the superconducting compound is compared with nonsuperconducting parent compound LaOFeAs. With fluorine doping, a shift of the shallow core level is observed in XPS spectra, which may be a response of the band structure due to fluorine doping in the system. The balance of the chemical potential shift with the screening effect of conduction electrons near the Fe and As ions is discussed using nearly unchanged Fe 2p and As 3d core-level spectra. The La 3d core-level spectra shift towards the high energy, ～0.36 eV, may be due to the chemical potential shift caused by fluorine doping. In our valence band spectra, a small peak at around 0.2 eV is observed, which disappeared with the fluorine doping in the system, indicating a change of Fe 3d state from low spin to high spin states and also confirming the nature of Fe 3d electrons as itinerant, which is responsible for superconductivity in these compounds.     

Synthesis of Silica Vesicles with Controlled Entrance Size for High Loading,Sustained Release,and Cellular Delivery of Therapeutical Proteins

A rationally designed two‐step synthesis of silica vesicles is developed with the formation of vesicular structure in the first step and fine control over the entrance size by tuning the temperature in the second step. The silica vesicles have a uniform size of ≈50 nm with excellent cellular uptake performance. When the entrance size is equal to the wall thickness, silica vesicles after hydrophobic modification show the highest loading amount (563 mg/g) towards Ribonuclease A with a sustained release behavior. Consequently, the silica vesicles are excellent nano‐carriers for cellular delivery applications of therapeutical biomolecules.