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The preparation and structural and dielectric properties of BaTi[O.sub.3]-CaTi[O.sub.3]-SrTi[O.sub.3] ternary system ceramics are described. The degree of the diffuseness and the relaxation of the ferroelectric-paraelectric phase transition are increased with Ca addition.

The discovery of a new I/O crystalline approximant (AC) that features interwoven networks of three-dimensional Penrose tiles close to those assumed for quasicrystals (QCs) is reported. The discovery based on results from Ca-Au-Ga system might provide insight into QC modeling and searching.

Broadband dielectric spectroscopy is used for examining the colossal dielectric constants in the samples of Ca[Cu.sub.3][Ti.sub.4][O.sub.12] (CCTO). The surface-related mechanism is discussed by assuming the formation of a metal-insulator diode and a combination of surface and internal barriers.

The fabrication of predominantly (100)-oriented Ca[Bi.sub.4][Ti.sub.4][O.sub.15] (CBTi) films on Pt (111)/Ti/Si[O.sub.2]/Si substrates is described. The results suggested that predominantly (100)-oriented CBTi can be used as a potential candidate for the future high-density ferroelectric random access memory (FeRAM).

An accurate density-functional method was employed to systematically explore the electronic structures and magnetic properties of CaN and CaC in the zinc-blende (ZB) phase. The results indicated that ZB-structure CaN and CaC at their respective equilibrium lattice constant are half-metallic (HM) ferromagnets which could find potential application in the field of spintronics.

A new vesicle phase system is constructed with tetradecyldimethylamine oxide ([C.sub.14]DMAO) and increasing amounts of [(C[H.sub.3][(C[H.sub.2]).sub.13]NHCOC[H.sub.2]OS[O.sub.3]).sub.2]Ca in aqueous solution. Vesicles are constructed through [Ca.sup.2+]-bridge complexation between an amine oxide surfactant and a sulfate surfactant and calcium oxalate monohydrates are produced through the vesicular phase as microreactors.

The defect chemistry of [Yb.sup.3+]:CaTi[O.sub.3] perovskite solid solutions is examined. Yb-doped CaTi[O.sub.3] ceramics are prepared by sintering and the dielectric properties of the final materials are measured as a function of temperature and frequency.

The crystal structure and microstructures of single-phase samples of [La.sub.1-x][Ca.sub.x]Mn[O.sub.3-[delta]] (LCMO), prepared by pulsed reactive crossed beam laser ablation on SrTi[O.sub.3] (STO) substrates, are studied. The structural transitions at high temperature have affected the thermopower behavior as well as the thermal conductivity values.

The microscopic studies of peptide phosphoprotein osteopontin (OPN) and calcium oxalate monohydrate (COM) crystal are reported. The results provide insight into the significant role of phosphate and carboxylate groups in a phosphoprotein-biomineral interaction.

The chemical solution deposition (CSD) of [Ca.sub.3][Co.sub.4][O.sub.9] (CCO349) films on LaAl[O.sub.3] (LAO) single crystal substrates and the effects of dewetting associated with strains are examined. The results have shown that CCO349 films are prepared by using the simple CSD method on LAO substrates, which has broadened the selection of substrates for large-scale production.

The first-principles density functional calculations are employed to explain the magnetic and electronic properties of Ca[Cu.sub.3][Cr.sub.4][O.sub.12] and Ca[Cu.sub.3][Cr.sub.2][Sb.sub.2][O.sub.12].

The study describes the synthesis of nonmetallate structures of CaTi[O.sub.3] using an in situ hydrothermal synthesis technique. These structures are found to have extremely controllable structures and excellent wettability.

Ternary diffusion coefficients for the lysozyme-Ca[Cl.sub.2]-water ternary system are described for examining the effect of calcium salts on the thermodynamic and transport properties of aqueous solutions of proteins. The neglecting of the common-ion contribution of the preferential-interaction coefficient has led to inaccurate descriptions of protein-salt aqueous systems, even at high salt concentrations.

The activations of factor XIII (FXIII) by IIa and by [Ca.sup.2+] as well as FXIIIa inhibition by the K9 Q isostere 6-diazo-5-oxo-norleucine (DON) peptide and iodoacetamine are examined. The results have shown that the activation and inhibition have led to local and long range effects to FXIII(a) and that many are affected by [Ca.sup.2+] binding.

The structural evolution of the self-assembled monolayer (SAM) and mineral are analyzed by examining the changes in order and bonding of mercaptophenol (MP) SAMs on Au(111) during the initial stages of mineral formation as well as the mechanism of amorphous calcium carbonate (ACC) to calcite transformation during template-directed crystallization. A preferential face of nucleation is seen for crystallization of calcite from ACC on the SAM surfaces despite the static structural disorder.

The calcium 5-amino isophthalate complex is synthesized from an equimolar reaction between {[Ca(O[H.sub.2])4](H2O)} and H2AIP in water. The IR spectrum shows a strong absorption in the region 3200-3500 [cm.sup.-1], indicating the presence of a large number of water molecules in the final product.

A new type of ternary Ca-[M.sup.IV]-OF complex is identified, where anionic metal(IV) hydroxide complexes are stabilized by the association/ion-pair formation with [Ca.sup.2+] ions , and are characterized by using extended X-ray absorption fine structure (EXAFS). The complex stoichiometries of these complexes are consistent with the dependencies of [Zr.sup.IV] and [Th.sup.IV] solubilities on pH and Ca[Cl.sub.2] concentration.

The texture analysis as well as the identification of two crystalline phases between a thin film of monoclinic [Ca.sub.3][Co.sub.4][O.sub.9] and a cubic (100) Si substrate is presented.

The adsorption of Calcium (Ca) on pristine and electron-irradiated poly surfaces is studied quantitatively to analyze the energy of adsorption, amount of Ca absorbed. The exposure of poly surfaces to electrons increases the initial sticking probability of Ca, but decreases its absorption energy.

Radio-frequency sputtering methods are used for depositing lead titanate thin films with different contents of Ca on Pt/Ti/Si[O.sub.2]/Si substrates to form [Pb.sub.1-x][Ca.sub.x]Ti[O.sub.3] (PCT) thin films. The analysis of the properties of pyroelectric infrared (PIR) sensors has disclosed that the voltage response and detectivity has increased with the Ca content.

[Pr.sub.0.5][Ca.sub.0.5]Mn[O.sub.3] (PCMO)/SrRu[O.sub.3] (SRO)/PCMO/MgO stacked-type junctions are fabricated by using a PCMO buffer layer on a MgO (001) substrate in order to examine the effect of crystallinity on the electric-field-induced insulator-metal (IM) transition. It is shown that the lattice deformation of the PCMo film, which has accompanied the transition from charge-ordered (CO) to charge-disordered (CDO) states, can occur if the PCMO films are oriented in multiple directions.

The design, synthesis and the biological utility of BiNiX, a photoactivatable ryanodine receptor (RyR) agonist, is reported. Focal photolysis has permitted activation of RyRs with high spatiotemporal precision, thereby indicating that BiNiX is a unique tool for probing RyR function in living cells.

The single-crystal X-ray diffraction technique is employed to analyze and report the structure and bonding the new transition-metals, namely [Ca.sub.2]Cd[Sb.sub.2] and [Yb.sub.2]Cd[Sb.sub.2], wherein the cation-anion interactions are found to be the structure driving factors. The results show that such structures exhibit narrow gap semiconducting and poor metallic behavior, as the inversion symmetry is absent in this case.

The structural, microstructural, and electronic properties of iodine intercalated [[[Bi.sub.(0.82)]Ca[O.sub.2]].sub.2][[Co[O.sub.2]].sub.(1.69)] misfit cobaltite are discussed. The coupling between the block-layer structure and the transport properties are described along with the description of some doping effects in the quasi-2D studied phase.

Spin-based magnetic molecular species are designed based on the exotic planar tetracoordinated carbon (ptC) radical C[Al.sub.3]Si and their spins are determined by the PtC radical (C[Al.sub.3]Si)-decks. The heterodecked sandwich scheme is testified to be an effective way to capture planar radicals and to design spin-based molecular materials.

The crystal structures of the calcium-bound con-G and con-T[K7[gamma]] dimeric short peptides at atomic resolution are explored. Results that the con-G dimer interface is completely different from the con-T[K7[gamma]] interface even though the metal chelation is similar in both the peptides.

A series of calcium [alpha]-aminocarboxylates are prepared by refluxing aqueous solutions/suspensions of calcium hydroxide and the respective [alpha]-amino acid and their crystal structures and spectroscopic properties are investigated. The structural diversity is observed with the binding modes of the aminocarboxylate ligands and the calcium environment, and besides terminal aminocarboxylate coordination, there are three diferent types of aminocarboxylate bridges.

The self-formation of quasiperiodic void structure inside the Ca[F.sub.2] crystal is described by using the single femtosecond laser beam. The results have shown that the length of the void array varied with the focal depth beneath the sample surface and have also provided an effective method of fabricating three-dimensional periodic microstructures inside various types of crystal materials.

The electrical pulse width, pulse polarity, film thickness, resistivity distribution, temperature dependence, device impedance, and dynamic properties of [Pr.sub.0.7][Ca.sub.0.3]Mn[O.sub.3] resistance random access memory (RRAM) devices are investigated. It is inferred that Jahn-Teller effect plays a significant role in the RRAM programming property and that the rise in the resistance of RRAM devices is because of localization of valence electrons in transition metal oxide by a high density of nonequilibrium electron packet injected into the resistor from the cathode.

An investigation was carried out about the specificity and the affinity of the interaction of the N-terminal sequences of annexins A1 and A2 with [Ca.sup.2.plus]-S100A11. The findings revealed that the binding site for annexin A2 on S100A11 was similar to that observed for the annexin A1 but with distinct differences involving the C-terminus of the annexin A2 peptide.

The characterization of the optical properties of natural nanostructured hydroxyapatite (HAp) [[Ca.sub.10][(P[O.sub.4]).sub.6][(OH).sub.2]] obtained from the bones of Brazilian river fish such as pintado, jau, and cachara. Structural analysis indicates a Ca/P ratio close to 1.67 (approximately 1.64 plusmn 0.04) and the presence of morphology and particle phase structure in the nanostructured HAp powder.

A genetic toolbox of natural and engineered protein modules is used to create several materials that form reversible networks in the presence of [Ca.sup.2+]. The modular framework can be extended to create a variety of new sensing materials using modules from the diverse array of signaling pathways that are mediated by reversible protein-protein interactions.

The analysis of the quantities of calmodulin (CaM) in S-1 and reS-1 is presented and successfully identify the single specific IQ motif as IQ2. The IQ1 and IQ2 motifs associate with CaM (not ELC), and high [Ca.sup.2+] concentrations induce dissociation of CaM specifically from IQ2, which results in a loss of BMV motor function.

A new approach based on a molten multicomponent precursor source was applied for the MOCVD fabrication of high quality CaCu3Ti4O12 (CCTO) thin films on various substrates. Epitaxial CCTO films were obtained on LaAlO3(100), no pure films were formed on SrTiO3(100) and the CCTO films grown on Pt/TiO2/SiO2/Si(100) were polycrystalline.

The syntheses of the new compounds CaNiGe2, SrNiGe2 and SrNiSn2 from the elements by arc melting techniques with subsequent annealing of the sample at 1270 K and the single-crystal X-ray diffraction methods to determine their structure is presented. Analyses of the electronic structures of CaNiGe2, SrNiGe2, and SrNiSn2, with the help of the electron localization function (ELF), indicate the coexistence of localized covalent and delocalized bonding between the metal atoms involved.

The electron energy-loss spectroscopy of O K edge in Ca[Al.sub.2][O.sub.4] is studied and the near edge fine structure of the O K edge is interpreted with the help of theoretical calculations in the ground-state approximation. Time-resolved electron energy-loss spectroscopy of O K has confirmed that the selective elimination of high-order coordinated Ca by electron irradiation results in a threshold shift of the O K edge.

Synchrotron radiation photoemission is used to examine the interfacial electronic structure of calcium and tris(8-hydroxyquinolato) aluminum (Al[q.sub.3]). As the cluster increases in size with increasing Ca thickness, the excess charge in the pyridyl ring starts to hop over other pyridyl rings, resulting in all nitrogen atoms in Al[q.sub.3] with excess charges and the decomposition of all Al[q.sub.3] molecules begins only when all N atoms are charged up.

A member of the aluminum hydride family, CaAl[H.sub.5] is formed during the decomposition of Ca(Al[H.sub.4])[.sub.2]. The crystal structure of this new compound was calculated by density functional theory band-structure calculations and confirmed by X-ray powder diffraction analysis.

The analysis of the (super 15)N{(super 31)P} rotational echo double resonance (REDOR) data is extended by examining the contribution of interactions between surface phosphorous atoms to the observed (super 15)N REDOR decay. The (super 31)P-(super 31)P dipolar couplings are incorporated and the method is applied to reanalyze the (super 15)N{(super 31)P} REDOR of the lysine side chain approaching the hydroxyapatite (HAP) surface.

Crystalline samples of carbon-doped CaB(sub 4) were synthesized by solid-state reactions in sealed niobium ampules from the elements Ca, B, and C. Crystals of CaB(sub 4-x) C(sub x) are black with a metallic luster and behave stable against mineral acids.

A study of the photosystem-II-associated 33-kDa extrinsic manganese-stabilizing protein undergoing pH-induced conformational changes in the physiological pH range is illustrated. The results indicate that the transition from the closed state at neutral pH to the open state at low pH is relevant for regulation of the binding of Mn(super 2+) and Ca(super 2+) and for the regulation of the function of the WOC.

The metal-ion complexing properties of the ligand EDTAM (ethylenediamine-N,N,N'N'-tetraacetamide) are investigated as a model for the role of amide oxygen donors in the binding sites of Ca-binding proteins. This resembles the metal-ion affinity patterns of binding sites in Ca-selective proteins for large metal ions, where amide oxygen donors are present.

Data from a high-resolution EXAFS method using a novel multicrystal monochromator is presented. It is concluded that two Mn-Mn distances of 2.73 and 2.82 angstrom in a 2:1 ratio can be resolved using this method, proving the presence of three short Mn-Mn vectors in the S1 and S2 states of the Mn4Ca cluster.

A spontaneous precipitation of calcium carbonate (CaCO3) was conducted from the aqueous systems containing a water-soluble polymer poly(vinylpyrrolidone) and an anionic surfactant sodium dodecyl sulfate (SDS). The results indicated that the self-organized configurations of the polymer/surfactant supramolecules dominate the morphologies of CaCO3 aggregates.

A structural model is developed for the apo-Entamoeba histolytica and its equilibrium folding to the completely folded holo state. The relative Ca(super 2+) binding affinities and specificities among the four metal binding sites is explained.

The geometric and electronic structures of poly(9,9-dicotylfluorene) (PFO) oligomer interacting with Ca atoms are studied. The geometric and electronic structures of complexes between PFO and Ca are revealed by studying their different interactions.

A Ca(super 2+) -binding site in the domain 1 rat cluster of differentiation 2 (CD2) with the desired structure and retained function was designed to understand the role of Ca(super 2+) binding. The study suggested that Ca(super 2+) binding has a differential effect on the rigidity of the residues depending on their flexibility and location within secondary structure.

An accurate characterization of the three-dimensional potential energy surface and vibrational-rotational energy levels of calcium dihydride is presented. The molecular parameters are determined by the ab initio approach using extensively correlated wave functions calculated with large correlation-consistent spdfgh basis sets and taking into account the 'outer-core' correlation effects of the calcium atom.

A study on the electron magnetic-resonance (EMR) probing of the changes in the magnetic structure of a CaMn(sub 1-y)Mo(sub y)O3 system during Mo doping of the Mn sites is presented. The results indicate that a strong difference is observed between the resonant properties of Mo- and Ru doped series at both paramagnetic and magnetically ordered states.

The successful design of a Ca(super 2+)- binding site in the non-Ca(super 2+)- binding cell adhesion protein CD2 is demonstrated. The designed protein, Ca.CD2, exhibits selectivity for Ca(super 2+) versus other di- and monovalent cations.