Multiphoton imaging with a direct‐diode pumped femtosecond Ti:sapphire laser

A direct‐diode pumped Ti:sapphire femtosecond oscillator is used to perform multiphoton imaging for the first time.     

Changes in Soluble and Bound Peroxidase—IAA Oxidase During Tomato Fruit Development

Soluble peroxidase activity increased dramatically during the early stages of tomato fruit development, reaching a maximum at the mature-green stage. Ionically and covalently bound peroxidases were also observed, and the activities of these fractions increased steadily throughout fruit development. IAA (indoleacetic acid) oxidase activity was observed in both soluble and bound fractions and paralleled the peroxidase activity. Tissue homogenates from juvenile fruit caused an extended induction period in IAA oxidation reactions catalyzed by the purified tomato fruit peroxidase, suggesting the occurence of a high concentration of phenolic-type auxin protectors in this tissue. As the fruit developed, tissue homogenates showed a reduction in the amount of auxin protectors as the IAA oxidizing capacity of the fruit increased.     

THREE TYPES OF CITRUS PEEL WASTE AS SOURCES OF COLOR

SUMMARY –Pilot-scale extractions of orange peel color concentrates from whole peel, peel frits and flavedo were reported. Yields of color up to 402, 545 and 669 mg/kg of starting material were obtained from frits, whole peel and flavedo, respectively. Additional color was obtained by acetone treatment of emulsion and this process increased yields by 1% from whole peel, 33% from flavedo and 50% from frits. All three of these waste materials appear to provide good sources of natural orange color. From the standpoint of yield, flavedo was best. Whole peel, although affording the lowest yield of color, offers the advantage of being considerably easier to handle due to lack of emulsion.     

SPECTRORADIOMETRY AND COLORIMETRY IN THE LIGHTING INDUSTRY

Spectroradiometry is fundamental in the measurement and evaluation of color. It is used in the evaluation of new light sources, in the analysis of problem areas, and for the compilation of data for inclusion in the technical brochures describing lighting products. The basic elements of a spectroradiometer are described and the application of spectral-power distribution measurements to photometry and colorimetry is illustrated.     

USE OF ULTRAFILTRATION/REVERSE OSMOSIS SYSTEMS FOR THE CONCENTRATION AND FRACTIONATION OF WHEY

SUMMARY– Existing ultrafiltration/reverse osmosis technology provides a means of fractionating and concentrating cheese whey into liquid fractions containing a variety of protein: lactose ratios. These ratios may range from about 1:8 (raw whey) through 3:5 (a "skim milk equivalent") to 2:1 or higher. If a two- or three-stage ultrafiltration system were used with water injection between stages, a product with a protein:lactose ratio of 20:1 could be obtained. The exact protein:lactose ratio in the concentrate stream is a function of the permeability and selectivity characteristics of the membrane, and the system design and operating conditions. Some of the sanitation problems associated with the introduction of these new unit operations in the dairy and food processing industries are also treated at length.     

Trajectory control of a PUMA robot arm by inversion and servocompensation

Based on invertibility and functional reproducibility, an approach to the control of the PUMA arm with six rotational degrees of freedom is presented. The control system has two important features: (i) the ability for fast, precise trajectory tracking; and (ii) robustness to uncertainty in the system, such as variable payload, inertia, etc. The control law derived using invertibility gives decoupled, independently controlled responses in each joint angle using torquers. For robustness, a first-order servocompensator is designed for each decoupled inner loop driven by the joint angle error. For smooth joint angle responses, a command generator is constructed that produces the reference trajectories to be tracked. Simulation results are presented to show that rapid, accurate trajectory following is achieved in the closed-loop system in spite of large payload uncertainty.     

Optimal Hankel-norm approximation approach to model reduction of large-scale Markov chains

A model reduction problem of certain large-scale Markov chains under an optimal criterion for Hankel-norm approximation is discussed. The multi-dimensional Markov chain under investigation is assumed to have a finite-dimensional stationary state-transition matrix, which is first reformulated as a multi-input/multi-output (MIMO) linear time-invariant (LT1) stochastic system. Consequently, the resulting large-scale MIMO LTI stochastic system has a closed-form best approximant in the Hankel-norm from a specified class of stable lower-dimensional MIMO LTI systems.