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Spontaneous desorption : field assisted ion induced desorption mass spectrometry
(1990)
Spontaneous desorption (SD) refers to the emission of ions and electrons from a flat surface biased at a few kV and placed a few mm in front of an extraction grid or aperture at ground. Using SD, time-of-flight mass spectra ...
Organometallic chemistry in unusual media : water and supercritical carbon dioxide as solvents for organometallic chemistry
(1994)
A series of water soluble transition metal complexes, utilizing the water soluble phosphine 1,3,5,-triaza-7-phosphaadamantane (PTA), were synthesized and studied. The water-soluble phosphine complex of Rh(I), (Rh(PTAH)(P ...
Surface modification of preformed polymeric materials : direct functionalization of reactive polymer surfaces
(1994)
Surface modifications of several reactive preformed polymeric materials, such as poly(methyl methacrylate) (PMMA), poly(ethylene terephthalate) (PET) and poly(vinyl chloride) (PVC) are described. Those modifications are ...
Studies on vitamin B12 biosynthesis and on 2,3-Oxidosqualene cyclase
(1994)
Vitamin B 12, the antipemicious anemia factor, is known to be the most complex nonpolymeric natural product derived from uroporphyrinogen III. Its coenzyme is the tetrapyrrolic cofactor involved in over 20 enzymatic ...
Studies of stereoselective reactions between 2-(trimethylsiloxy)- furan and imines
(1993)
A new, general method for the preparation of 5-aminoalkyl-furan-2(5H)-ones has been developed, and the details of the reaction have been studied. 5-Aminoalkylfuran-2(5H)-ones, which contain two chiral centers, were synthesized ...
Spectroscopic studies of refractory and dielectric thin films
(1993)
This work demonstrated the application of the techniques and methodology of surface science to investigate the mechanisms of thin film deposition processes on solid surfaces. The synthesis of boron nitride (BN) thin films ...
Studies of enzymes on the Vitamin B12 pathway : mechanistic studies of Uroporphyrinogen III synthase and function analysis of four methylases
(1993)
Several plasmids were constructed to generate Uro'gen III synthase using different expression systems. The C-1 azafulvene intermediate in the reaction of Uro'gen III synthase was trapped using NH4CI and NaBH4 to generate ...
Synthesis and structural characterization of layered metal phosphonates, metal phosphites, and their intercalation compounds
(1993)
Two types of layered lanthanum phosphonates have been prepared and characterized by XRD, TGA, NMR and ER. The one form ed at pH< 3 has a composition of LaH(C>3 PR)2 (R= CH3, C2H 5 , C^Hs) and the other prepared at pH > 8 ...
Ion detection and structural mass spectrometry by Fourier transform ion cyclotron resonance mass spectrometry and matrix assisted laser desorption ionization
(1994)
The work presented in this thesis focuses on detection and structural mass spectrometry of large biomolecules by MALDI-FTICR. In Chapter I, overviews of the MALDI technique and advantages of FTICR are given. In Chapter II, ...
Study of the solution properties of octahedral metal-halide clusters of early transition metals : electronic spectroscopy and cluster excision in zirconium halide cluster phases
(1994)
This dissertation presents the excision of Zr-based clusters from cluster-containing extended phases. The details of the methods for cluster excision we have developed are presented and possible future directions outlined. ...