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Sampling synthesis is one of the most
practical and widely used approaches among the various sound synthesis methods
used for creating a realistic simulation of acoustic instruments. Using
numerous high quality sound samples it is possible to reproduce a sound of
almost any musical instrument, including subtle variations caused by the
registers of an instrument or through the use of different articulation
techniques and dynamic levels. However, this method has some disadvantages.
Firstly, with high fidelity reproduction systems, the repeatability of samples
becomes quickly apparent for more experienced listeners. This is sometimes
manually corrected by switching between several different samples of the same
note. Secondly, it is standard approach to record and reproduce each note
separately. It prevents samplers from reproducing natural note transitions,
making fluent, connected articulations, such as legato, unnatural. Finally,
samplers provide a very limited number of sound parameters to control.
Therefore, it is difficult to introduce a set of purposeful fluctuations of
selected parameters uniquely attributable to human performances. A synthesis
system which addresses the aforementioned problems has been developed at the
Academy of Music in Krakow (Poland) for a group of wind instruments as part of
a symphony orchestra. The system is based on a large collection of non-standard
samples. Samples contain short sequences of notes instead of single notes. In
order to use them, a number of techniques have been implemented to allow the seamless
connecting of recorded sequences and the control of note durations as well as
tempo and dynamics envelopes. Decision-making algorithms and signal processing
are applied to create melodic figures by choosing, modifying, and connecting
fragments of samples, while keeping natural note transitions intact. The
problem of mimicking human performances is addressed by implementing a set of
performance rules. It allows to introduce context-dependent variations into the
regular playback of the material contained in the musical notation to properly
shape the expression of musical structures, similarly to that of live performances
by musicians. This article presents the main modules of the modified sampling
synthesis system designed by us as well as its general structure and principle
of operation. The modules are responsible for performing musical score
analyses, an automatic selection and connection of sound samples, and the
application of performance rules.
ZnO can be made into many nanostructures that have unique properties for advanced applications, such as piezoelectric and pyroelectric materials. ZnOnanorod is one of the nanostructures that possess advanced properties. This paper reports a gas phase flame process to continuously synthesize aerosols of ZnOnanorods in large quantities. Unlike previous work, our process shows that pure ZnOnanorods can be made in a freestanding form rather than growing on a substrate surface. It was found that the ZnOnanorods preferentially grow in the thermodynamically stable direction  in the gas phase with different aspect ratios, depending on flame process conditions. The ZnOnanorod aerosols are highly crystalline and have a hexagonal geometry. Raman and photoluminescence spectroscopic studies showed that there are no structural defects in the nanorods, which have energy band gap of 3.27 eV in the near UV region. It was demonstrated that the gas phase flame reactor can provide a convenient means for continuous production of highly pure aerosols of ZnOnanorods.
In this study, we report the microwave assisted synthesis of Phospholamban protein (WT-PLB) as a new gold standard in solid phase peptide synthesis. Microwave energy offers benefits for both the coupling and deprotection reactions during peptide synthesis. The use of microwave energy for both the coupling and deprotection steps makes the microwave peptide synthesizers the most versatile and powerful systems available. It produces high yield and fast synthesis when compared to conventional peptide synthesizers.