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The structures of monolayers on Si(100) made up of two acetyl-protected triol ligands, derived from 2-hydroxymethyl-propane-1,3-diol, namely, R-C(CH2OAc)3with R = CH2CH−(CH2)9−O−CH2− and R = CH2CH−(CH2)7−, have been investigated. After deprotection, the two ligands are well-suited receptors for anchoring molecular functionalities, such as Fe4single molecule magnets, to the Si surface through OH groups. Monolayers were obtained by the hydrosilylation reactions between H-terminated Si(100) and the CH2CH− end groups and were prepared in pure form or diluted with inert 1-alkenes to achieve an accurate control over the concentration and concerted orientation of the receptors on the surface. Subsequent anchoring of a Fe4cluster, especially designed for a vertical atom sequence, has been expedient to clarify the influence of ligand mole fraction on the ordering of molecular receptors. We have achieved insight into the related structures and morphologies by combining angle-resolved X-ray photoelectron spectroscopy (AR-XPS), FTIR-attenuated total reflection (ATR) spectroscopy, and atomic force microscopy (AFM), including force lithography experiments. There is evidence that steric hindrances of apical groups are crucial for surface concentrations and, in turn, for geometrical orientation of the tethering units. Aging effects on monolayer structures and possible recovery processes have also been evaluated.

A gas-phase route such as molecular layer deposition has been applied for the first time to create a monolayer of metalorganic Eu(III) molecules on NiO oxide layer. The surface of the as-deposited NiO layer is activated using H2O/O2vapors, and then functionalized by anchoring molecules of the Eu complex working at different temperatures to favor the chemisorption process. The effects of the activation process and of the MLD temperature on the chemisorption of the Eu complex were evaluated through in-depth X-ray photoelectron and luminescence spectroscopy studies. These analyses allowed to define the stoichiometry of the Eu moiety chemisorbed on the surface and the optimization of an impressive strategy to the synthesis of hybrid metalorganic/inorganic systems. The hybrid system's luminescence properties have proved the monolayer's energy conversion phenomena and produced further information about the local environment around the Eu(III) anchored as a complex on the NiO surface.

A hierarchical hybrid inorganic–organic system suited for the recognition of aromatic volatile organic compounds on brushlike ZnO fibers was synthetized. The hybrid material was obtained by a multistep approach based on the growth of ZnO nanorods onto electrospun ZnO fibers (average diameter 200 nm). The obtained nanostructured ZnO brushlike fibers (overall diameter 2 μm) were functionalized through the grafting of a bifunctional phosphonic linker (12-azidododecylphosphonic acid) followed by the anchoring of a specific cavitand receptor. The linker was anchored on ZnO fibers through the phosphonic group while the azide terminations reacted with a quinoxaline-bridged cavitand (QxCav) having four alkyne groups via “click” reaction. The anchoring steps were monitored through the evolution of the FT-IR features in the 3200–2800 cm–1region due to C–Hxstretches and in the 2200–2000 cm–1region due to the azide and alkyne groups of the phosphonic linker and QxCav. The recognition properties of this hybrid nanostructure toward α,α,α-trifluorotoluene vapors were evaluated by XPS and Raman measurements.

In this paper, we use X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy to investigate the structural and morphological properties of methylammonium lead iodide (MAPbI3) thin films deposited on flat TiO2substrates, as obtained with and without the use of chlorine precursors. We demonstrate that the presence of Cl precursors assists the growth of oriented MAPbI3domains along a specific growth direction. Such features are attributed to the proximity of the Cl species to the interface with the TiO2substrate.

Pr1–xCaxMnO3thin films have been deposited through an insitumetal organic chemical vapor deposition (MOCVD) process using a molten multi‐metal source, consisting of the Pr(hfa)3·diglyme, Ca(hfa)2·tetraglyme, and Mn(tmhd)3precursor mixture on single crystal substrates such as LaAlO3(001) and MgO (001). Optimization of processing parameters has allowed the deposition of homogeneous thin films in morphology, composition, and thickness. The effect of substrate has been assessed in relation to structure and morphology. Field emission scanning electron microscope of a Pr0.7Ca0.3MnO3film deposited at 1000 °C on MgO (001).

Thin nanoporous TiO2layers, deposited by dc reactive sputtering, have been functionalized with a novel unsymmetrical Zn(II) phthalocyanine (ZnPc-II) bearing a push–pull system, properly designed for application in dye sensitized solar cells. The anchoring process has been studied by combining visible absorption (vis), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) in order to investigate the molecular assembly during the early stage of the sensitizing process. The vis and XPS measurements indicate that the ZnPc-IIsurface density (dsurf, molecules/cm2) and its binding geometry are strongly affected by the concentration of the grafting solutions. It has been observed that the ZnPc-IIsurface density monotonically increases by increasing the solution concentration up to a saturation of dsurf∼ 1.0 × 1013molecules/cm2. Angle resolved XPS analyses indicate that at low molecular surface density a strong interaction between the ZnPc-IIaromatic macrocycle and the TiO2surface occurs, suggesting a planar binding geometry. The increase of the molecular surface density is accompanied by a mitigation of the surface–molecule interaction that leads to a different ZnPc-IIbinding geometry. Conductive atomic force microscopy has demonstrated that the charge transport through the dye–TiO2interface strongly depends on the binding arrangements which exhibit different threshold values in the local I–V characteristics.

Si(100) and porous silicon substrates have been engineered with cavitand modified salen molecules. A salen derivative, specifically designed for covalently anchoring on silicon, was grafted onto Si(100) surfaces by photochemical hydrosilylation, and onto porous silicon by thermal hydrosilylation. These hybrid systems have been studied by different analytic techniques. Monochromatized X‐ray photoelectron spectroscopy (XPS) was used to characterize both flat and porous samples. Atomic force microscopy (AFM) and, in particular, atomic force lithography (AFL) were used to evaluate the monolayer structure and morphology of the flat silicon surface, while Fourier transform infrared spectroscopy (FTIR) was adopted to probe the hydrosilylation process involving porous samples. The uranyl complex of the salen derivative was directly synthesized on the silicon surface by the reaction between Si‐anchored salen and uranyl acetate. This surface‐based synthesis suggests that the salen molecules are intact and keep their specific properties after silicon anchoring.

Self-nanostructured ZnO:Al conductive layers consisting of [112̅0] oriented domains were coated by a conformal TiO2thin film and sensitized by 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) to be used as transparent conductive electrodes in dye-sensitized solar cells. In addition to the higher surface availability due to the nanopatterning, the TCPP surface density increases by 330% (UV−vis) with respect to a flat conventional substrate thanks to a more dense molecular arrangement, as evidenced by combining high-resolution X-ray photoelectron spectroscopy and atomic force microscopy. Furthermore, the presence of zinc atoms in the TiO2overlayer (Ti(:Zn)O2) crucially influences the electronic properties of the assembled TCPP. As a consequence of the orbitals' rearrangement attributed to the presence of zinc, a significant quenching of luminescence is observed in the emission spectra of TCPP-sensitized Ti(:Zn)O2, suggesting that electrons could be more effectively injected from the molecular orbitals to the conduction band of the semiconductor.

A multistep route for the covalent anchoring of 5amino1,10phenanthrolinetrisdibenzoylmethaneeuropiumIIImolecules on silicon 100 has been developed. The anchoring route consists of Si functionalization with Nhydroxysuccinimide NHS activated carboxylic acid, followed by nucleophilic substitution at the carboxylic acid sites. Characterization of the resulting Si based hybrid materials was achieved by using several complementary techniques: Xray photoelectron spectroscopy XPS, attenuated total reflection FTIR spectroscopy ATRFTIR, AFM and fluorescence spectroscopy. Comparison of results obtained for NHS activated Si surfaces with those of inert alkyl functionalized Si surfaces proved the covalent anchoring of the Eu complex and ruled out the presence of physisorbed Eu species. The 1.8 nm thickness of the grafted layer, estimated by atomicforce lithography, is compatible with the presence of the anchored complex on the surface. Fluorescence measurements proved that luminescence properties are retained in the grafted complex.

Bottom‐up fabrication of 3D organic nanostructures on Si(100) surfaces has been achieved by a two‐step procedure. Tetradentate cavitand 1was grafted on the Si surface together with 1‐octene (Oct) as a spatial spectator by photochemical hydrosilylation. Ligand exchange between grafted cavitand 1and self‐assembled homocage 2, derived from cavitand 5bearing a fluorescence marker, led to the formation of coordination cages on Si(100). Formation, quantification, and distribution of the nanoscale molecular containers on a silicon surface was assessed by using three complementary analytical techniques (AFM, XPS, and fluorescence) and validated by control experiments on cavitand‐free silicon surfaces. Interestingly, the fluorescence of pyrene at ≈4 nm above the Si(100) surface can be clearly observed.

A synthetic strategy to control the density of Mn12clusters anchored on silicon(100) was investigated. Diluted monolayers suitable for Mn12anchoring were prepared by Si‐grafting mixtures of the methyl 10‐undecylenoate precursor ligand with 1‐decene spectator spacers. Different ratios of these mixtures were tested. The grafted surfaces were hydrolyzed to reveal the carboxylic groups available for the subsequent exchange with the [Mn12O12(OAc)16(H2O)4]⋅4 H2O⋅2 AcOH cluster. Modified surfaces were analyzed by attenuated total reflection (ATR)‐FTIR spectroscopy, X‐ray photoemission spectroscopy (XPS), and AFM imaging. Results of XPS and ATR‐FTIR spectroscopy show that the surface mole ratio between grafted ester and decene is higher than in the source solution. The surface density of the Mn12cluster is, in turn, strictly proportional to the ester mole fraction. Well‐resolved and isolated clusters were observed by AFM, using a diluted ester/decene 1:1 solution.

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The receptor for the type 1 insulin-like growth factor (IGF-I) has been implicated in cellular transformation and the acquisition of an invasive/metastatic phenotype in various tumors. Following ligand binding, the IGF-I receptor is internalized, and the receptor.ligand complex dissociates as the ligand is degraded by endosomal proteinases. In the present study we show that the inhibition of endosomal IGF-I-degrading enzymes in human breast and murine lung carcinoma cells by the cysteine proteinase inhibitors, E-64 and CA074-methyl ester, profoundly altered receptor trafficking and signaling. In treated cells, intracellular ligand degradation was blocked, and although the receptor and two substrates, Shc and Insulin receptor substrate, were hyperphosphorylated on tyrosine, IGF-I-induced DNA synthesis, anchorage-independent growth, and matrix metalloproteinase synthesis were inhibited. The results suggest that ligand processing by endosomal proteinases is a key step in receptor signaling and function and a potential target for therapy.

Growth kinetics of Cu2O and CuO films has been studied using the CuIIacetylacetonate precursor in a low‐pressure (11.3 Torr) MOCVD reactor. Pure Cu2O forms in the 2.7–6 Torr PO2and 0–3 mTorr PCu(acac)2ranges at deposition temperature of 300°C. Beyond 3.74 Torr PO2, Cu2O films show a ′111′ texturing. Conclusive evidence for the occurrence of a Langmuir–Hinshelwoold mechanism, involving non‐competitively adsorbed reagents, has been obtained. Above 8 Torr PO2CuO films have been grown under a reaction rate limited regime at temperatures as low as 285°C. The apparent activation energies are 18 ± 2 kJ/mol and 22 ± 3 kJ/mol at 0.7 and 2 mTorr PCu(acac)2, respectively. The present data are consistent with a kinetic model for CuO formation based on the surface reaction between reversibly adsorbed molecular Cu(acac)2and weakly adsorbed O2. The dependence of kinetic parameters upon the temperature brings about a 40 ± 6 kJ/mol value of the heat of adsorption of the molecular precursor. Homogeneous and smooth surfaces are associated with Cu2O ′111′ oriented films. Homogeneous surfaces with a greater grain size (0.2–0.4 μm), are observed for CuO. Randomly oriented Cu2O samples are much less homogeneous with grain size ranging from 50 nm to 0.5 μm.

Upon the binding of insulin or epidermal growth factor to their cognate receptors on the liver parenchymal plasmalemma, signal transduction and receptor internalization are near co-incident. Indeed, the rapidity and extent; of ligand mediated receptor internalization into endosomes in liver as well as other organs predicts that signal transduction is regulated at this intracellular locus. Although internalization has been thought as a mechanism to attenuate ligand mediated signal transduction responses, detailed studies of internalized receptors in isolated liver endosomes suggest an alternative scenario whereby selective signal transduction pathways can be accessed at this locus.

Upon the binding of insulin or epidermal growth factor to their cognate receptors on the liver parenchymal plasmalemma, signal transduction and receptor internalization are near co-incident. Indeed, the rapidity and extent; of ligand mediated receptor internalization into endosomes in liver as well as other organs predicts that signal transduction is regulated at this intracellular locus. Although internalization has been thought as a mechanism to attenuate ligand mediated signal transduction responses, detailed studies of internalized receptors in isolated liver endosomes suggest an alternative scenario whereby selective signal transduction pathways can be accessed at this locus.

Nanometer-sized copper metal can be formed by UV irradiation of ethanol bis(2,4-pentanedionate)copper(ii) solutions: simple tuning of the irradiation conditions switches the process from homogeneous to heterogeneous nucleation, and promotes the formation of either colloidal powders or nanostructured films.

Nanometer-sized copper metal can be formed by UV irradiation of ethanol bis2,4-pentanedionatecopperii solutions: simple tuning of the irradiation conditions switches the process from homogeneous to heterogeneous nucleation, and promotes the formation of either colloidal powders or nanostructured films.

Administration of warfarin during pregnancy may cause a rare syndrome characterized by nasal hypoplasia, usually associated with stippled epiphyseal and extraepiphyseal calcifications resembling chondrodysplasia punctata. A case of chondrodysplasia punctata after warfarin with 18 months follow-up is reported.

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