Effect of variations in acid properties of HZSM-5 on the coking behavior and reaction stability in butene aromatization

In order to investigate the effect of acid properties on the coke behavior and stability of butene aromatization, we prepared the AHZSM-5 samples with various acid properties by the methods of hydrothernial treatment and K addition. The reaction of butene aromatization was carried out at 350 degrees C and 0.5 MPa in a continuous flow fixed bed. The characterization of the fresh/coked catalysts with NH3-TPD, N-2 adsorption-desorption measurement, and TG techniques has shown that a large amount of acid sites (high acid density) of the AHZMS-5 catalyst can cause a large quantity of coke deposit and serious channel blockage, and so result in a rapid loss of aromatization activity. On the contrary, after a great reduction in strong acid sites of AHZSM-5 catalyst resulting from some K-modification, the presence of only many weak acid sites also could not lessen the formation of coke nor improve the reaction stability of butene aromatization. Interestingly, the simultaneous reduction in the strong and weak acid sites to a desirable level by hydrothermal treating the AHZSM-5 catalyst at a proper temperature can effectively suppress the coke formation and channel blockage, and thus improve its olefin aromatization stability. (c) 2005 Elsevier B.V. All rights reserved.

Variations in total and differential milk somatic cell counts and plasmin levels and their role in proteolysis and quality of milk and cheese

Increased plasmin and plasminogen levels and elevated somatic cell counts (SCC) and polymorphonuclear leucocyte levels (PMN) were evident in late lactation milk. Compositional changes in these milks were associated with increased SCC. The quality of late lactation milks was related to nutritional status of herds, with milks from herds on a high plane of nutrition having composition and clotting properties similar to, or superior to, early-mid lactation milks. Nutritionally-deficient cows had elevated numbers of polymorphonuclear leucocytes (PMNs) in their milk, elevated plasmin levels and increased overall proteolytic activity. The dominant effect of plasmin on proteolysis in milks of low SCC was established. When present in elevated numbers, somatic cells and PMNs in particular had a more significant influence on the proteolysis of both raw and pasteurised milks than plasmin. PMN protease action on the caseins showed proteolysis products of two specific enzymes, cathepsin B and elastase, which were also shown in high SCC milk. Crude extracts of somatic cells had a high specificity on αs1-casein. Cheeses made from late lactation milks had increased breakdown of αs1-casein, suggestive of the action of somatic cell proteinases, which may be linked to textural defects in cheese. Late lactation cheeses also showed decreased production of small peptides and amino acids, the reason for which is unknown. Plasmin, which is elevated in activity in late lactation milk, accelerated the ripening of Gouda-type cheese, but was not associated with defects of texture or flavour. The retention of somatic cell enzymes in cheese curd was confirmed, and a potential role in production of bitter peptides identified. Cheeses made from milks containing high levels of PMNs had accelerated αs1-casein breakdown relative to cheeses made from low PMN milk of the same total SCC, consistent with the demonstrated action of PMN proteinases. The two types of cheese were determined significantly different by blind triangle testing.

Heavy metals in the asteroid Asterias rubens and its prey Mytilus edulis: Seasonal and geographical variations in four selected North Sea biotopes

info:eu-repo/semantics/published

Significant variations of Anti-Müllerian hormone serum levels during pregnancy and during oral contraception

info:eu-repo/semantics/nonPublished

AN EXAMINATION OF 19TH CENTURY AUSTROGERMAN VIOLIN SONATAS

For my dissertation recital project, I traced the course of the violin-piano sonata in Austro- German in the 19th century, after Beethoven. My project presented works in three general categories. First, I presented works that are frequently-played standards of the violin sonata repertoire, works by Johannes Brahms, Franz Schubert, and Robert Schumann. The Second category is works by composers better known for their other compositions: Felix Mendelssohn and Richard Strauss. Finally, I choose the works seldom played these days, but worth of consideration, by Carl Maria von Weber and Max Reger. For my first recital, I performed Schubert's Violin Sonata, No. 1, Op. 137 in D major, Schumann's Violin Sonata, No. 1, Op. 105 in a minor, and Brahms' Violin Sonata, No.3, Op. 108 in d minor, with Naoko Takao as pianist. My second recital included works of Weber's Sonata, No. 1, Op. lob, in F major, Mendelssohn's Sonata, in F major (1838), and Schumann's Sonata, No.Z,Op.121 in d minor with Grace Cho. I concluded my final recital with the works of Reger's Violin Sonata, No. 1, Op. 1 in d minor and Strauss' Violin Sonata, Op. 18 in E flat major, Soo-Young Jung at the piano. All three programs are documented in a digital audio format available on compact disc, with accompanying programs also available in digital format.

JOACHIM, BRAHMS, AND SCHUMANN: THE FLOURSHING OF NINETEENTHCENTURY VIOLIN REPERTOIRE

The cultivation of violin repertoire and its ultimate dominance of the late Nineteenth-Century orchestral library are best examined through the analysis and study of the works of Joseph Joachim (1831-1907), Johannes Brahms (1833-1897), and Robert Schumann (1810-1856). Each of these men, in their own right, made significant contributions to the development of violin repertoire during the latter half of the Nineteenth Century. Yet their achievements were also the result of a collaborative effort and shared influence, the absence of which would have yielded a diminutive musical landscape, especially in the concerti of Brahms and Joachim. This dissertation explores Joachim’s technical dexterity and its influence on Brahms and Schumann, and further studies the vital role Brahms and Schumann played in forming Joachim as both composer and editor. The pieces examined in this dissertation evidence the significant influence each of these composers shared. Three chamber compositions stand as guideposts in the analysis and establish a stylistic foundation to collaborative efforts among Joachim, Brahms, and Schumann. The preliminary recital focuses on these chamber pieces which illustrate the individual style of each composer, featuring Joachim’s Romance, Op. 2, written between 1848 and 1852, Schumann’s Second Sonata, Op. 121, written in 1851, and Brahms’ Second Sonata, Op. 100, written in 1886. A second performance includes the enigmatic F-A-E Sonata of Brahms, Schumann, and Albert Deitrich, Schumann’s pupil, as well as Joachim’s Second Concerto. A collaborative effort, the F-A-E Sonata represents Brahms’ and Schumann’s efforts to write with Joachim’s unbridled style and technique in mind. An even greater musical offering, Joachim’s Second Concerto, a gift to Brahms in 1860, has been called the “Holy Grail” of concertos, and is considered the preeminent display of Joachim’s creative genius by incorporating demanding technical challenges and Hungarian-like overtones. The third and final program features Brahms’ Concerto in D Major. A fitting response to Joachim’s gift 17 years later, Brahms’ Concerto was written for Joachim at the height of his career, bearing the performer’s stylistic elements throughout. The recital also includes various Hungarian Dances by Brahms. While the Dances were not original to Brahms, they further illustrate the underlying idiom of Hungarian folk music in both Brahms’ and Joachim’s art.

IMPROMPTU: FROM PUBLISHER'S IMPULSE TO AN ESTABLISHED SMALL­ SCALE GENRE IN PIANO LITERATURE

The word 'impromptu' began to appear in music literature in the early 19th century, specifically as title for a relatively short composition written for solo piano. The first impromptus appear to have been named so by the publishers. However, the composers themselves soon embraced the title to indicate, for the most part, fairly short character pieces. Impromptus do not follow any specific structural pattern, although many are cast in ternary form. The formal design ranges from strict compound ternary in the early impromptus to through-composed and variation forms. The peak of impromptu's popularity undoubtedly came during the middle and late19th century. However, they are still being composed today, albeit much less frequently. Although there have been many variants of impromptus in relation to formal design and harmonic language over the years, the essence of impromptu remains the same: it is still a short character piece with a general feeling of spontaneity. Overall, impromptus may be categorized into several different groups: some appear as part of a larger cycle, such as Dvorak's G minor Impromptu from his Piano Pieces, B. 110; many others use an element of an additional genre that enhances the character ofthe impromptu, such as Liszt's Valse-Impromptu and Antonio Bibalo's Tango Impromptu; yet another group consists of works based on opera themes, such as Liszt's Impromptu Brillant sur des themes de Rossini et Spontini and Czerny's Impromptus et variations sur Oberon, Op. 134. My recording project includes well-known impromptus, such as Schubert's Op. 142 and the four by Chopin, as well as lesser known works that have not been performed or recorded often. There are four impromptus that have been recorded here for the first time, including those written by Leopold Godowsky, Antonio Bibalo, Altin Volaj, and Nikolay Mazhara. I personally requested the two last named composers to contribute impromptus to this project. My selection represents works by twenty composers and reflects the different types of impromptus that have been encountered through almost three hundred years of the genre's existence, from approximately 1817 (VoriSek) to 2008 (Volaj and Mazhara).

The Evolution of Rachmaninov's Pianistic Style from 1892 to 1941 as Seen in Selected Original Works and Transcriptions for Piano

Unlike some other major composer-pianists (Franz Liszt and Alexander Scriabin being the most notable examples), Sergei Rachmaninov did not experience any dramatic changes in his compositional style; one can, however, notice certain stylistic differences between piano works composed during different periods of his long creative life. This dissertation argues that a clear evolution of Rachmaninov's pianistic style through his three creative periods can be traced by examining a selection of his compositions, from his first significant cycle for piano, 5 Marceaux de fantaisie, Op. 3 (1892), all the way through to his last piano work, a transcription of P.I.Tchakovsky's Lullaby, Op. 16, No. 1 (1941). Rachmaninov's life as a composer can be divided into three periods. His early period was ended abruptly by the disastrous premiere ofhis First Symphony in 1897, which caused a deep psychological crisis in the life of the young composer. Piano works of this period are often characterized by relatively simple homophonic texture, when Rachmaninov was clearly influenced by some of his Russian predecessors, most notably Tchaikovsky. His second and most productive period, also known as the period of"Russian maturity," started in 1900, when he began working on the Second Suite for two pianos, Op. 17, and the Second Concerto, Op. 18; this phase ended with the Russian Bolshevik revolution of 1917. Works of this time exhibit a mature style of piano writing, with rich, virtuosic - often considered excessive by many critics - texture and ever-increasing use of chromatic harmonies. Rachmaninov's works of the third period are limited in number owing to the composer's preoccupation with a career as pianist. Original works for piano now give way to revisions of earlier compositions and transcriptions: Rachmaninov's piano writing becomes more efficient and economical without losing any of its virtuosic brilliance. This dissertation project examines in detail, over the course of three piano recitals, a variety of works composed during the "Russian maturity" period, from several Preludes from Op. 23 (1903), the first major cycle for solo piano of the period, to 9 Etudes-Tableaux, Op.39 (1917), the last one; the early period is represented by 3 of 5 Marceaux defantaisie, Op. 3 (1892), while the late period is shown through several piano transcriptions and revised versions of the remaining 2 pieces from Op. 3.

THE GREAT RUSSIAN PIANO TRADITION: SELECTED REPERTOIRE BY TCHAIKOVSKY, RACHMANINOFF AND PROKOFIEV

This dissertation explores representative piano music by three great Russian composers: Tchaikovsky, Rachmaninoff and Prokofiev. The areas of research include: 1) the short character piece; 2) the Russian piano transcription tradition; 3) the concerto and sonata cycle; 4) extra-musical imagery; 5) the influence of popular and dance music of the period. Perhaps the most important result of this research is learning how the art of incorporating a singing quality at the piano stands at the center of Russian pianistic heritage. The first recital features compositions by Sergei Prokofiev. The Seventh Sonata exhibits rebellious, uncompromisingly dissonant treatment of its musical content. Ten Pieces from “Cinderella” shows an ascetic approach to piano texture - a common characteristic in Prokofiev’s late works. The Third Concerto is Prokofiev’s masterpiece in the genre. One of the 20th century’s most performed concerti, it overflows with pianistic challenges. For my second dissertation recital, I have chosen Peter Ilich Tchaikovsky’s The Seasons. These short character pieces were inspired by literary sources. The text portrays Russian rural life, nature, moments of intimate reflection, and imaginary experiences and impressions. Tchaikovsky’s gift as a melodist and remarkable musical individualist is represented in his two Nocturnes as well as in the Nutcracker Suite, masterfully transcribed by Mikhail Pletnev. The final program features Sergei Rachmaninoff’s Ten Preludes, Op. 23, regarded as a culmination of the turn-of-the-century grand Russian pianistic style. The Fantasy Pieces helped establish Rachmaninoff’s reputation as a pianist-composer, a profoundly lyrical poet of the piano. The three Rachmaninoff transcriptions, the Minuet, the Hopak and the Polka de W.R. preserve the spirit of the Golden Era’s musical salon. These pieces were written to delight and dazzle audiences with their bold character, musical taste, virtuosic tricks and technical finesse. The three recitals comprising this dissertation were presented in Gildenhorn Recital at the University of Maryland School of Music on November 13, 2010, April 11, 2011 and February 27, 2012. The recitals were recorded on compact discs and are archived within the Digital Repository at the University of Maryland (DRUM).

THE GREAT RUSSIAN PIANO TRADITION: SELECTED REPERTOIRE BY TCHAIKOVSKY, RACHMANINOFF AND PROKOFIEV

This dissertation explores representative piano music by three great Russian composers: Tchaikovsky, Rachmaninoff and Prokofiev. The areas of research include: 1) the short character piece; 2) the Russian piano transcription tradition; 3) the concerto and sonata cycle; 4) extra-musical imagery; 5) the influence of popular and dance music of the period. Perhaps the most important result of this research is learning how the art of incorporating a singing quality at the piano stands at the center of Russian pianistic heritage. The first recital features compositions by Sergei Prokofiev. The Seventh Sonata exhibits rebellious, uncompromisingly dissonant treatment of its musical content. Ten Pieces from "Cinderella" shows an ascetic approach to piano texture - a common characteristic in Prokofiev's late works. The Third Concerto is Prokofiev's masterpiece in the genre. One of the 20th century's most performed concerti, it overflows with pianistic challenges. For my second dissertation recital, I have chosen Peter Ilich Tchaikovsky's The Seasons. These short character pieces were inspired by literary sources. The text portrays Russian rural life, nature, moments of intimate reflection, and imaginary experiences and impressions. Tchaikovsky's gift as a melodist and remarkable musical individualist is represented in his two Nocturnes as well as in the Nutcracker Suite, masterfully transcribed by Mikhail Pletnev. The final program features Sergei Rachmaninoff's Ten Preludes, Op. 23, regarded as a culmination of the turn-of-the-century grand Russian pianistic style. The Fantasy Pieces helped establish Rachmaninoff's reputation as a pianist-composer, a profoundly lyrical poet of the piano. The three Rachmaninoff transcriptions, the Minuet, the Hopak and the Polka de W.R. preserve the spirit of the Golden Era's musical salon. These pieces were written to delight and dazzle audiences with their bold character, musical taste, virtuosic tricks and technical finesse. The three recitals comprising this dissertation were presented in Gildenhorn Recital at the University of Maryland School of Music on November 13, 2010, April 11, 2011 and February 27, 2012. The recitals were recorded on compact discs and are archived within the Digital Repository at the University of Maryland (DRUM).

SELECTED ICONIC CHAMBER MUSIC WORKS WITH PIANO FROM THE NINETEENTH AND TWENTIETH CENTURIES

Chamber music repertoire featuring the piano blossomed from the mid-nineteenth through the early twentieth century. The quantity of works increased greatly during this time and the quality of these works reached the highest level. Among the many symbolic works that were composed were sonatas for a single string instrument with piano, piano trios, quartets: and quintets as well as two-piano works and four-hand duets. Being able to study and perform many of these iconic works before I graduated was one of the major goals I set for myself as a collaborative pianist. The abundance of repertoire has made it easy to choose works considered "iconic" for my dissertation's three recitals. Iconic is defined as "very famous or popular, especially being considered to represent particular opinions or a particular time" in the online Cambridge Advanced Leamer's Dictionary & Thesaurus © Cambridge University. The compositions featured in the recitals were composed from 1842 through 1941, including works by Schumann, Brahms, Faure, Rachmaninoff, Ravel, and Lutoslawski. Choosing the repertoire with my fellow performers in mind was an important part of this dissertation. In addition to trying to make balanced programs which include variety, working with different instruments and performers is one of the most fulfilling parts of the musical experience for me as a collaborative pianist. Joining me for the concerts were members of the Aeolus String Quartet (violinist Nicholas Tavani, violinist Rachel Shapiro, violist Greg Luce, and cellist Alan Richardson), pianist Hsiao-Ying Lin (a doctoral student from the Peabody Conservatory), and my colleagues from the Peabody Institute Preparatory Division (faculty violinist Dr. Christian Tremblay and cellist Alicia Ward), and Derek Smith, Associate Principal violist of the Annapolis Symphony Orchestras). The three recitals were performed in the Gildenhom and Ulrich Recital Halls at the University of Maryland, College Park, Maryland. They are recorded on CD and available on compact discs, which can be found in the Digital Repository at the University of Maryland (DRUM).