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We examined the magnetic, structural, and chemical properties of CoFe 2 O 4 films deposited on Al 2 O 3 substrates using RF-magnetron sputtering under Ar and Ar + O 2 environments. Perpendicular magnetic anisotropy with large magnetization was observed in the case of the film deposited under the Ar + O 2 environment. However, no significant anisotropy appeared in the film deposited under the Ar environment. Interestingly, depth-dependent X-ray photoelectron spectra showed nearly identical stoichiometric ratios of Co/Fe and oxygen vacancies regardless of the deposition environment. Structurally, high-quality crystallinity with in-plane compressive strain, and lower surface and interfacial roughness were induced in the film deposited under the Ar + O 2 environment. Cross-sectional transmission electron microscopy and X-ray reflectivity measurements showed that oxygen not only suppressed the deposition rate but also increased the electron density of the film, resulting in better crystallinity. Hence, the presence of oxygen during deposition should be considered as one of the essential parameters for improving the structural and magnetic properties of ferrite films. [ABSTRACT FROM AUTHOR]

Beamline 8A (BL 8A) is an undulator‐based soft X‐ray beamline at Pohang Accelerator Laboratory. This beamline is aimed at high‐resolution ambient‐pressure X‐ray photoelectron spectroscopy (AP‐XPS), soft X‐ray absorption spectroscopy (soft‐XAS) and scanning photoemission microscopy (SPEM) experiments. BL 8A has two branches, 8A1 SPEM and 8A2 AP‐XPS, that share a plane undulator, the first mirror (M1) and the monochromator. The photon beam is switched between the two branches by changing the refocusing mirrors after the monochromator. The acceptance angle of M1 is kept glancing at 1.2°, and Pt is coated onto the mirrors to achieve high reflectance, which ensures a wide photon energy range (100–2000 eV) with high resolution at a photon flux of ∼1013 photons s−1. In this article, the main properties and performance of the beamline are reported, together with selected experiments performed on the new beamline and experimental system. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a nickel (Ni) catalyst with large surface area supported by a graphitic layer is proposed. The graphitic layer is formed on a Ni foil by chemical vapor deposition (CVD) using CH 4 as a source. The Ni foil is partially etched by a chemical etchant to increase the surface to volume ratio. The H 2 generation rates of the catalysts for different Ni etching times are measured and their surfaces are observed using an optical microscope. The optimized Ni etching time is 6 h, and the catalyst prepared by 6 h of etching shows an H 2 generation rate of about 600 ml/min⋅(g metal). The 6-h etched Ni/graphitic layer (Ni/G) is reused five times to confirm durability; it shows a high performance without any degradation. The H 2 generation rate for different concentrations of NaBH 4 is measured. The reaction follows first order kinetics, which means that the higher the concentration of NaBH 4 is, the faster the H 2 generation is. Highlights • Nickel foil with increased surface area showed excellent catalytic performance. • A graphitic layer prevents nickel from tearing or damaging. • The rate of hydrogen generation of sodium borohydride is about 600 ml/min·(g metal). • The catalyst showed excellent stability even after 5 repetitions. [ABSTRACT FROM AUTHOR]

Abstract While controlling the cation contents in perovskite rare-earth nickelate thin films, a metal-to-insulator phase transition is reported. Systematic control of cation stoichiometry has been achieved by manipulating the irradiation of excimer laser in pulsed laser deposition. Two rare-earth nickelate bilayer thin-film heterostructures with the controlled cation stoichiometry (i.e. stoichiometric and Ni-excessive) have been fabricated. It is found that the Ni-excessive nickelate film is structurally less dense than the stoichiometric film, albeit both of them are epitaxial and coherent with respect to the underlying substrate. More interestingly, as a temperature decreases, a metal-to-insulator transition is only observed in the Ni-excessive nickelate films, which can be associated with the enhanced disproportionation of the Ni charge valence. Based on our theoretical results, possible origins (e.g. anti-site defects) of the low-temperature insulating state are discussed with the need of future work for deeper understanding. Our work can be utilized to realize unusual physical phenomena (e.g. metal-to-insulator phase transitions) in complex oxide films by manipulating the chemical stoichiometry in pulsed laser deposition. Highlights • Cation stoichiometry in nickelate ceramic targets is controlled by laser irradiation treatment. • A Ni-excessive bilayer nickelate film exhibits the metal-to-insulator transition. • Anti-site Ni defects can induce the observed metal-to-insulator transition. [ABSTRACT FROM AUTHOR]

Semiconductor quantum dots have intriguing electronic and optical properties distinguished from bulk owing to quantum confinement effects. Among the two-dimensional materials, black phosphorus (BP) has generated enormous excitement due to its tunable direct band gap and high p-type semiconducting properties. We prepared BP quantum dots (BPQDs) by simple liquid exfoliation using distilled water and ethanol solution. Our structural data show the uniform distribution of circular BPQDs with the average lateral size of 4.08 ± 0.66 nm and the height of 1.13 ± 0.32 nm. We fabricated BPQD field-effect transistors (FETs) to investigate the electrical characteristics of BPQD-based devices and found that both hole and electron transport can be probed in the BPQD FETs. The BPQD FETs exhibited unprecedentedly ambipolar behavior with the mobility of 0.11 cm 2 V −1 s −1 for p type and 0.09 cm 2 V −1 s −1 for n type at 300 K. Our results provide the simple preparation methods to fabricate ambipolar BPQD FETs with the comparable hole and electron transport for large-area applications in solar cells and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The asymmetric response of the cation distribution on [0 0 1] oriented CoFe 2 O 4 films were examined. Depending on the deposition temperature and substrates (MgO(0 0 1) or SrTiO 3 (0 0 1)), the films exhibited a range of compressive or tensile strain states along the out-of-plane. With increases in deposition temperature, the initial compressive (tensile) strain for the films grown on MgO(0 0 1) (SrTiO 3 (0 0 1)) was reduced. Furthermore, the out-of-plane (in-plane) magnetic anisotropy of the film grown on MgO(0 0 1) (SrTiO 3 (0 0 1)) decreased with increasing deposition temperature. The uniaxial magnetic anisotropy energy calculation based on the magnetic anisotropy (crystalline and shape) and strain of films confirmed that the strain reduction with increasing deposition temperature is the main source of the uniaxial magnetic anisotropy reduction, regardless of the sign of the strain. X-ray photoelectron spectroscopy explained the saturation magnetization variation by the cation distribution depending on the strain state. Furthermore, the calculated magnetic moment based on the cation distribution were well matched for the high crystalline films. [ABSTRACT FROM AUTHOR]

Understanding the structure-activity relationship over silica-supported Au-based bimetallic nanocatalysts in CO oxidation is essential in elucidating active sites and catalytic mechanisms. Here, we uncover that structure-activity relationship over a silica-supported 10 nm sized AuCu bimetallic model nanocatalyst for CO oxidation. Oxygen–induced atomic restructuring of AuCu nanocrystals is comprehensively investigated using combined operando spectroscopic and microscopic techniques, including near-ambient-pressure X-ray photoelectron spectroscopy, diffuse reflectance infrared Fourier-transform spectroscopy, and environmental transmission electron microscopy. We show that the formation of CuO x /Au heterostructure gives rise to the enhancement of catalytic activity for CO oxidation. The formation of the reactive heterostructure on catalysis was rationalized by density functional theory calculation. Our results indicate that intermediate heterostructure with a metal-oxide interface leads to strong electronic coupling between catalyst and support (i.e. , electronic metal-support interaction effect). [Display omitted] • Understanding the EMSI effect via atomic restructuring on bimetallic catalyst. • Oxygen-induced structural evolution on AuCu nanoparticle forms CuO x –Au interface. • CuO x –Au interface in AuCu catalysts drives catalytic synergy for CO oxidation. • Demonstrated a catalytic role of the CuO x –Au interface with DFT calculation. [ABSTRACT FROM AUTHOR]

The thermal transport growth of various metal oxide (MO x ) nanostructures using graphene as a catalytic layer was studied. Graphene was synthesized by Cu-catalyzed chemical vapor deposition and transferred onto a SiO 2 -covered Si substrate using bubble transfer methods. Due to the catalytic activity of the atomic-thick carbon layer, control of the position of the MO x nanostructures as well as the growth parameters, such as nucleation density and growth rate, could be achieved. The position-selective and density-controlled MO x nanostructures were evaluated for hydrogen gas sensor applications, where different responses were obtained with hydrogen molecules. [ABSTRACT FROM AUTHOR]

We synthesized poly-trimethoxyphenylsilane (PTMS) and applied it as the carrier film to CVD graphene transfer process for the first time. Since the PTMS particles are not fully crosslinked due to the presence of bulky groups, they do not have crystallinity in the long-range order on the graphene surface and are easily removed by solvent such as toluene. Raman, AFM, and X-ray photoemission (especially, Si 2p signal) analysis confirmed that the surface of the transferred graphene was clean without PTMS impurities. [ABSTRACT FROM AUTHOR]

This study examined the microscopic aspects of macroscopic physical property variations of hydrogen annealed VO 2 films, deposited on Al 2 O 3 (0001) substrates by RF magnetron sputtering. The temperature-dependent electrical resistivity showed that the as-grown film exhibited a metal-insulator-transition (MIT) at 55.20 °C and 49.26 °C during heating and cooling, respectively. On the other hand, no MIT was observed for the film annealed under a hydrogen environment. Spectroscopic measurements during the in-situ hydrogenation process showed that hydrogen annealing (∼0.3 mbar, up to 300 °C) promoted the V 3+ state above 100 °C. Raman spectroscopy and X-ray diffraction confirmed that the as-grown film changed from a monoclinic to rutile structure during hydrogen annealing. In addition, the shift of the (020) diffraction peak position of the hydrogen-annealed film to a lower angle compare to that of the known rutile VO 2 film was attributed to the expansion of the unit cell. In addition, local structure analysis showed that an increase in octahedral symmetry after hydrogen annealing is one of the main explanations for the metallic characteristics of the hydrogen-annealed film. [ABSTRACT FROM AUTHOR]

Amorphous CoFe 2 O 4 films with different thicknesses were deposited on MgO(001) substrates to examine the correlation between the oxygen vacancy and magnetic properties of the films. As the film thickness increased, the films became packed and smooth with well-defined interfaces. The magnetic hysteresis loop on the out-of-plane and in-plane showed an increased saturation magnetization and decreased coercivity when the film thickness was increased. Furthermore, the number of oxygen vacancies decreased with increasing films thickness. Those observations suggest that the presence of the correlation between the magnetic property variations and number of oxygen vacancies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon chemical state on the surface during annealing process. • In-situ XPS to reveal the surface and sub-surface chemical states. • More amount of C-solute presents on the surface than the subsurface. The microstructure that governs the nature of carbon steel is determined by the combination of iron and carbon. Ferrite and austenite differ in their arrangements of iron atoms, and they differ from cementite with respect to iron and carbon bonding. In this work, we combine structural studies (X-ray diffraction, scanning electron microscopy, and atomic force microscopy) and synchrotron-based in-situ X-ray photoelectron spectroscopy (XPS) to demonstrate the behavior of the carbon in carbon steel using a thermal annealing process conducted from room temperature to 900 °C in an ultrahigh-vacuum chamber. In situ XPS experiments revealed not only that the chemical states varied depending on depth from the surface but also that the carbide changed into the C-solute phase at temperatures between than 300–600 °C. Our findings provide important insights into the subtle balance of interactions involving the properties of steel that differ between the surface and bulk phases, offering new opportunities to engineer the properties of carbon steel. [ABSTRACT FROM AUTHOR]

A performance test of near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) at Korean Basic Science Institute (KBSI) in Daejeon, Korea is carried out. The NAP-XPS at KBSI is equipped with SPECS PHOIBOS 150 analyzer and 2-dimensional-delay line detector, which provides improved detection efficiency with 1-dimensional chemical imaging mode. The in-situ gas-pressure cell is designed to operate at pressure up to 25 mbar with differential pumping scheme. A micro-focused Al Kα X-ray source is utilized as photon excitation source. The NAP-XPS is composed of two separate chambers, e.g. a main preparation chamber and a measurement chamber, which hold a low energy electron diffraction, a high pressure cell, an ion sputter gun, a multi-cell E-beam evaporators, and a four-axis manipulator with heating and cooling capability. As a test run of NAP-XPS, a CO oxidation experiment is carried out on Pt 3 Ti polycrystalline surface. During the active phase of CO oxidation, a clear formation of Ti oxide is found on surface, revealing the intriguing role of surface metal oxide in surface chemical reaction. [ABSTRACT FROM AUTHOR]

The current–voltage ( I – V ) characteristics of Al/p-type Si Schottky diodes with pristine and 5 wt.% sorbitol-doped organic PEDOT:PSS interlayers have been investigated. It was found that the barrier heights of the diodes with pristine and sorbitol-doped PEDOT:PSS are higher than those of a conventional Al/p-type Si Schottky diode because of the modification of the effective barrier height by the organic interlayer. It is noted that the Al/p-type Si Schottky diode with sorbitol-doped PEDOT:PSS interlayer exhibits higher barrier height and lower series resistance, as compared to Al/p-type Si Schottky diodes with pristine PEDOT:PSS interlayer. In addition, UPS measurements indicate that the position of the HOMO level is closer to the Fermi level for pristine PEDOT:PSS than for sorbitol-doped PEDOT:PSS. As a result, the hole injection barrier height is 0.15 eV lower in the pristine PEDOT:PSS structure than in the sorbitol-doped PEDOT:PSS. This value closely matches the difference in barrier heights (0.12 eV) seen in the I – V measurements. An energy-level alignment diagram is also presented and discussed for the structures studied. The Poole–Frenkel mechanism is found to dominate the reverse leakage current in both structures, indicating the presence of structural defects and trap levels in the organic film. [ABSTRACT FROM AUTHOR]

The Inverse Spin Hall Effect (ISHE) voltage induced by spin-pumping was measured in Pt/[nonoxidized or oxidized NiFe] samples. The spectrum shape of the DC voltage signal was well-reproduced by simple Lorentzian functions, which were consistent with the prediction of ISHE in Pt/nonoxidized NiFe sample. On the other hand, the voltage signal from the Pt/oxidized NiFe was significantly decreased in accordance with abnormal ferromagnetic resonance (FMR) behavior. The origin of the ISHE voltage degradation was investigated by the FMR spectrum and X-ray photoelectron spectroscopy (XPS) analyses. The spin-pumping was suppressed by the oxidation of NiFe layer and deficient Pt/NiFe interface. The well-defined ferromagnet and clear interface with a normal spin mixing conductance were experimentally demonstrated to be reasonable spin-pumping. [ABSTRACT FROM AUTHOR]

Highlights: [•] TiO2 nanoparticles entrapped in aminoclay matrix were synthesized. [•] Microalgae harvesting efficiency was achieved ∼85% at 3.0g/L injection. [•] ∼95% of microalgae cells was disrupted by photocatalysis within 3h. [•] Integration of harvesting/lipid-extraction steps was demonstrated. [ABSTRACT FROM AUTHOR]

Highlights: [•] The T–FC was firstly synthesized by wet-chemical processing and ultrasound irradiation. [•] This T–FC exhibited higher visible-light photocatalytic and antibacterial activities. [•] The T–FC can be easily recovered from water using a magnet. [•] Moreover, the T–FC exhibits excellent photocatalytic stability. [ABSTRACT FROM AUTHOR]

Highlights: [•] The F-ZnO-m was fabricated at low temperature (65°C) with controlled seed adsorption. [•] The photocatalytic activity of F-ZnO-m was found to be higher than that of other ZnO photocatalyst. [•] Moreover, F-ZnO-m exhibited excellent antibacterial activity. [•] The recycling photocatalytic and antibacterial activities of F-ZnO-m shows good stability. [ABSTRACT FROM AUTHOR]

Highlights: [•] The u-MFN were synthesized via a ultrasound irradiation and/or calcinations process. [•] The u-MFN exhibited excellent adsorption capacities. [•] The u-MFN also displayed excellent adsorption of organic polluent after recycling. [•] The u-MFN has the potential to be used as an efficient adsorbent material. [Copyright &y& Elsevier]

Highlights: [•] The 3D a-TiO2 was synthesized at low temperature by hydrothermal processing and ultrasound irradiation. [•] The ultrasound irradiation aids in crystallizing 3D a-TiO2 without thermal treatment. [•] The 3D a-TiO2 was composed of urchin-like structures that were assembled by rod-like polycrystals. [•] The photocatalytic and antibacterial activities of 3D a-TiO2 was found to be higher than that of P25. [•] Moreover, the 3D a-TiO2 exhibits excellent photocatalytic stability. [ABSTRACT FROM AUTHOR]

Highlights: [•] The N-3D TiO2 was synthesized at low temperature via a modified hydrothermal process and ultrasound irradiation. [•] The N-3D TiO2 is irradiated with visible-light (*N-3D TiO2) to improve the hydroxylation of its surface. [•] The N- and *N-3D TiO2 exhibited excellent photocatalytic and antibacterial activities. [•] Moreover, the *N-3D TiO2 exhibits excellent photocatalytic stability. [ABSTRACT FROM AUTHOR]

Highlights: [•] The nanoporous N-TiO2 photocatalysts were successfully synthesized at room-temperature. [•] The *N-TiO2 was irradiated with visible-light to improve the surface hydroxylation of the N-TiO2 surface. [•] The N- and *N-TiO2 exhibited excellent photocatalytic and antibacterial activities. [•] Moreover, the *N-TiO2 exhibits excellent photocatalytic stability. [Copyright &y& Elsevier]

Highlights: [•] The C11TiO2-40 photocatalysts were successfully synthesized at room-temperature. [•] The photocatalytic activity of C11TiO2-40 was found to be higher than that of Degussa P25 and 5-nm sized anatase TiO2. [•] The recycling photocatalytic activity of C11TiO2-40 in our study shows good stability. [Copyright &y& Elsevier]

Abstract: We report highly visible-light active nanoporous carbon-doped TiO2 (C-TiO2) and sulfur-doped TiO2 (S-TiO2) for environmental and biomedical applications. C-TiO2 and S-TiO2 were synthesized at room temperature without thermal treatment using modified sol–gel processing and ultrasound irradiation. Under visible-light irradiation, the highest photocatalytic activity for S-TiO2 ([k]=3.121h−1) was found to be 28 times higher than that of undoped nanoporous TiO2 ([k]=0.112h−1). The recyclability of the S-TiO2 photocatalyst was found to be high with the decolorization rate at ∼92% of the initial value after fifteen cycles. Very interestingly, the C-TiO2 and S-TiO2 photocatalysts (crystallite size∼5.5nm) showed very strong antimicrobial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) compared to 5nm anatase TiO2 and undoped TiO2 photocatalysts after visible-light exposure for 3h. More than ∼95% of E. coli was killed, even after ten cycles of use for the S-TiO2 photocatalyst. Thus, we have demonstrated that C-TiO2 and S-TiO2 can serve as multifunctional generic bactericides, as well as highly visible-light active photocatalysts. [Copyright &y& Elsevier]

Abstract: Anatase–brookite bicrystalline TiO2 photocatalysts were successfully synthesized by a surfactant-assisted sol–gel route. Cetyltrimethylammonium chloride and tetra-n-butyl titanate were used as a surfactant and a titanium precursor, respectively. The bicrystalline TiO2 photocatalyst samples were aged at different temperatures (RT~100°C) and were found to have different morphologies, crystallinities, and surface areas. The photocatalytic activity of each sample was investigated by measuring the photodecomposition of reactive black 5 (RB5) and rhodamine B (Rho B). The photodecomposition rate ([k]=1.396h−1) of the sample prepared at 100°C was twice as high as that of Degussa P25 ([k]=0.707h−1) and three times as high as that of 5-nm-sized anatase TiO2 particles ([k]=0.471h−1). [Copyright &y& Elsevier]

Regioregular poly(3-hexylthiophene) (RR-P3HT) nanorod arrays were prepared on the indium tin oxide (ITO) substrate by capillary force in a vacuum oven (0.855 torr, 250 °C) using a drop-coating of RR-P3HT and anodic aluminium oxide (AAO) templates. The AAO templates were prepared by a two step anodizing process in an oxalic acid electrolyte. The templates had a highly ordered structure with a uniform pore diameter of ∼55–80 nm and cell lengths of ∼100–3930 nm. With suitable temperature and capillary force in the vacuum oven, the drop-coated RR-P3HT solution infiltrated the AAO templates. After removal of the AAO template, the RR-P3HT has a nanorod array form, with diameters of ∼55 nm and heights of ∼70 nm. [ABSTRACT FROM AUTHOR]

Three new octyloxy substituted spirobifluorenes, 2,7-diphenyl-3′,6′-bis(octyloxy)-9,9′-spirobifluorene (DPBSBF, 1a), 2,7-dibiphenyl-3′,6′-bis(octyloxy)-9,9′-spirobifluorene (DBBSBF, 1b) and 2,7-diterphenyl-3′,6′-bis(octyloxy)-9,9′-spirobifluorene (DTBSBF, 1c) were prepared. All the compounds had been fully characterized by 1H and 13C NMR, UV–Vis, DSC, mass spectrometry and gave satisfactory elemental analyses. They possessed good solubility in common organic solvents and good homogeneous film formation. The optical energy band gap of DBBSBF was 3.27 eV between the HOMO energy level, 5.85 eV, measured by UPS and the LUMO, 2.58 eV, calculated from absorption spectrum. A blue organic light emitting diode (OLED) based on the structure of ITO/TPD (60 nm)/DBBSBF (40 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (100 nm) showed good performance. The luminance of 3125 cd/m2 was observed at a drive voltage of 12.8 V and the colour coordinate in CIE chromaticity was (0.14, 0.12). The external quantum efficiency was obtained to be 2.8% at 100 cd/m2. [Copyright &y& Elsevier]

Copper nitride nanoparticles supported on a mesoporous superparamagnetic silica microsphere exhibit superior activity toward the Huisgen cycloaddition of azides and alkynes. The nitride catalyst offers significant advantages over homogeneous Cu catalysts. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the structural and electrical properties of metal-oxide-semiconductor (MOS) devices with Er metal gate on SiO2 film. Rapid thermal annealing (RTA) process leads to the formation of a high-k Er-silicate gate dielectric. The in situ high-voltage electron microscopy (HVEM) results show that thermally driven Er diffusion is responsible for the decrease in equivalent oxide thickness (EOT) with an increase in annealing temperature. The effective work function (Φ m,eff) of Er metal gate, extracted from the relations of EOT versus flat-band voltage (V FB), is calculated to be ∼2.86eV. [Copyright &y& Elsevier]

Fluorescent carbon nanomaterials, especially zero-dimensional (0D) carbon nanodots (CDs), are widely used in broad biological and optoelectronic applications. CDs have unique characteristics such as strong fluorescence, biocompatibility, sun-light response, and capability of mass-production. Beyond the previous green CD obtained from harmful natural substances, we report a new type of fluid-based fluorescent CD paints (C-paints) derived from polyethylene glycol (PEG; via simple ultrasound irradiation at room temperatures) and produced in quantum yields of up to ~14%. Additionally, C-paints possess a strong, UV- and visible-light-responsive photoluminescent (PL) property. Most especially, C-paints, by incorporation into a photocatalytic system, show additional roles in the emission of fluorescent light for activation of TiO2 nanoparticles (NPs) and the resultant detoxification of most organic dyes, thus further enabling embarkation in advanced water purification. [ABSTRACT FROM AUTHOR]

Over the past few decades, two-dimensional (2D) and layered materials have emerged as new fields. Due to the zero-band-gap nature of graphene and the low photocatalytic performance of MoS2, more advanced semiconducting 2D materials have been prompted. As a result, semiconductor black phosphorus (BP) is a derived cutting-edge post-graphene contender for nanoelectrical application, because of its direct-band-gap nature. For the first time, we report on robust BP@TiO2 hybrid photocatalysts offering enhanced photocatalytic performance under light irradiation in environmental and biomedical fields, with negligible affected on temperature and pH conditions, as compared with MoS2@TiO2 prepared by the identical synthesis method. Remarkably, in contrast to pure few layered BP, which, due to its intrinsic sensitivity to oxygen and humidity was readily dissolved after just several uses, the BP@TiO2 hybrid photocatalysts showed a ~92% photocatalytic activity after 15 runs. Thus, metal-oxide-stabilized BP photocatalysts can be practically applied as a promising alternative to graphene and MoS2. [ABSTRACT FROM AUTHOR]