Dinuclear Azide-Bridged Copper(II) Complex as Building Block for the Assembly of a 2D-Supramolecular Array

A novel Schiff base-copper(II) complex [Cu(2)L(2)(N(3))(2)](ClO(4))(2) 1, where L = (4-imidazolyl)ethylene-2-amino-1-ethylpyridine (apyhist), containing azide-bridges between adjacent copper ions in a dinuclear arrangement was isolated and characterized both in the solid state and in solution by X-ray crystallography and different spectroscopic techniques. Azide binding constants were estimated from titrations of the precursor [CuL(H(2)O)(2)](2+) solutions with sodium azide, giving rise to the azido-bridged species, [Cu(2)L(2)(N(3))(2)](2+). Raman spectra showed asymmetric stretching band at 2060 cm(-1), indicating the presence of azido ligands with a symmetric mu(1,) (1) binding geometry. EPA spectra, in frozen methanol/water solutions at 77 K, exhibited characteristic features of copper centers in tetragonal pyramidal coordination geometry, exhibiting magnetic interactions between them. Further, in solid state, two different values for magnetic coupling in this species were obtained, J/k = -(5.14 +/- 0.02) cm(-1) attributed to the mu(1, 1) azide-bridge mode, and J`z`/k = -(2.94 +/- 0.11) cm(-1) for the interaction between dinuclear moieties via water/perchorate bridges. Finally, an attempt was made to correlate structure and magnetic data for this dinuclear asymmetric end-on azido bridged-copper(II) 1 complex with those of another correlated dinuclear system, complex [Cu(2)L(2)Cl(2)](ClO(4))(2) 2, containing the same tridentate diimine ligand, but with chloro-bridged groups between the copper centres.

Block Copolymers Containing (R)-3-Hydroxybutyrate and Isosorbide Succinate or (S)-Lactic Acid Mers

A new aliphatic block copolyester was synthesized in bulk from transesterification techniques between poly((R)-3-hydroxybutyrate) (PHB) and poly(isosorbide succinate) (PIS). Additionally, other two block copolyesters were synthesized in bulk either from transesterification reactions involving PHB and poly(l-lactide) (PLLA) or from ring-opening copolymerization of l-lactide and hydroxyl-terminated PHB, as result of a previous transesterification reactions with isosorbide. Two-component blends of PHB and PIS or PLLA were also prepared as comparative systems. SEC, MALDI-TOF mass spectrometry (MALDI-TOFMS), (1)H and (13)C NMR spectroscopy, WAXD, solubility tests, and TG thermal analysis were used for characterization. The block copolymer structures of the products were evidenced by MALDI-TOFMS, (13)C NMR, and WAXD data. The block copolymers and the corresponding binary blends presented different solubility properties, as revealed by solubility tests. Although the incorporation of PIS sequences into PHB main backbone did not enhance the thermal stability of the product, it reduced its crystallinity, which could be advantageous for faster biodegradation rate. These products, composed of PHB and PIS or PLLA sequences, are an interesting alternative in biomedical applications.

Time Evolution of the Activation Energy in a Batch Chemical Oscillator

The batch-operated bromate/phosphate/acetone/dual catalyst system was studied at four temperatures between 5 and 35 degrees C. The dynamics was simultaneously followed by potential measurements with platinum and bromide selective electrodes, and spectroscopically at two different wavelengths. By simultaneously recording these four time series it was possible to characterize the dynamics of the sequential oscillations that evolve in time. The existence of three sequential oscillatory patterns at each temperature allowed estimating the activation energies in each case. Along with the activation energy of the induction period, it was possible to trace the time evolution of the overall activation energy at four different stages as the reaction proceeds. The study was carried out for two different sets of initial concentrations and it was observed that the overall activation energy increases as reactants turn into products. This finding was propounded as a result of the decrease in the driving force, or the system`s affinity, of the catalytic oxidative bromination of acetone with acidic bromate, as the closed system evolves toward the thermodynamic equilibrium.

Spring into summer : a novel

Spring into Summer is a novel based on my experiences as a student living in London for a year. The central character, an American under-graduate student studying history, attempts to complete a piece of work by his older brother who is killed in a car accident several months prior to his brother's departure for England. The narrative traces the younger brother's efforts and eventual failure to work on the history; in so doing, he also fails to become more like his older brother whom he greatly loved and admired. Thus, a doppelganger, or "Double" of sorts is used. Most of the action of the novel is set in London. However, the main character also travels to Dublin, York, and several other places in the British Isles, thereby giving a more complete picture of the experiences an American student undergoes while living abroad. During a year which many people might see as an escape from the problems and pressures of everyday life, the central character is forced to undergo a painful process of self-examination, resulting in his reevaluation of himself, his priorities, and his ambitions.

The LaGuardia Review, 1977 Spring

- PUBLISHING STAFF: Publisher, JOHN M. O'SHAUGHNESSY; Business Manager, EILEEN MURRAY Layout, MONICA VECCHIO; Art Director, PETER BROWN; CONTRIBUTORS: C. Freeman Sleeper, Lorence A. Long, John A. Williams, John Hyland, Sarah Lanier Barber, Judith Gomez,

Perspective: LaGuardia Community College Newsletter (Spring 1981)

Vol.9 No.1 Spring 1981; Perspective is a quarterly publication of LaGuardia Community College / CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Information on news and features stories should be addressed to the office In room M194. Faculty and staff news items should be sent to Dr. Roberta Matthews, Associate Dean of Faculty, room SB65.

Listing of Faculty Publications, Spring 1982

The Library Media Resources Center is happy to publish this revised Listing of Faculty Publications. As you recall, the first edition was issued in 1979 and so, 2 1/2 years later, it is our pleasure to present a larger and more complete edition... Special thanks to Professor Albert Talero who did all the editing and arrangements for the publication. Thanks also to Professor Fred Low for making the TRS-80 wordprocessing facilities of the LaGuardia Automated Library System (LALS) available for this edition. --Ngozi Agbim, April 23, 1982; 51 p.

Perspective: LaGuardia Community College Newsletter (Spring 1983)

Vol. 11 No.2; Perspective is a quarterly publication of LaGuardia Community College / CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Information on news and features stories should be addressed to the office In room M194. Faculty and staff news items should be sent to Dr. Roberta Matthews, Associate Dean of Faculty, room SB65.

Perspective: LaGuardia Community College Newsletter (Spring 1984)

Vol. 12 No.2; Perspective is a regular publication of LaGuardia Community College/CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Information on news and features stories, as well as faculty and staff notes, should be addressed to the office in room M413.