[en] Highlights: • We show a discrete Fe₂TiO₅-incorporation in hematite to improve the performance. • It can be well coupled with surface P-modification with a synergetic effect. • It shows a high photocurrent of 2.90 mA/cm² at 1.23 VRHE with Co-Pi catalysts. • It provides a good insight to understand other Ti-based treatments of hematite. Hematite is a promising photocatalyst for solar water splitting while its performance has been severely limited by various factors. Recently surface Fe₂TiO₅ layer was widely reported to enhance the performance of hematite with a favorable band position to facilitate hole transport. Here we further show that the Fe₂TiO₅-incorporation in bulk hematite can also improve the performance with faster charge separation. Moreover, it can be well coupled with surface P-modification to simultaneously improve charge separation and hole transfer with a synergetic effect. The Ti and P co-modified hematite shows a significantly enhanced photocurrent of 2.37 mA/cm² at 1.23 V vs. RHE when compared to the pristine value of 0.85 mA/cm². After coupling with Co-Pi catalysts, the hematite sample can even achieve a stable, high photocurrent of 2.90 mA/cm² at 1.23 V vs. RHE. The design of Ti and P co-modified hematite hollow nanostructures can be used as a promising candidate for solar water splitting applications. The discrete Fe₂TiO₅-incorporation also provides a good insight on the mechanism to understand other Ti-based treatments of hematite.

[en] The objectives of the confirmatory surveys were to provide independent contractor field data reviews and to generate independent radiological data for use by the NRC in evaluating the adequacy and accuracy of the licensee's procedures and survey results.

[en] Complete text of publication follows. The crystal symmetry of hematite in the basal plane predicts three easy magnetization axes for the antiferromagnetic spins. Spin canting then leads to three preferred magnetization axes perpendicular to these easy axes. We measured magnetic hysteresis loops and remanence curves on single hematite crystals as a function of rotation angle in order to verify this prediction and to better understand the interplay between spin canting, remanence and magnetic susceptibility. While our results qualitatively coincide nicely with theoretical predictions, a quantitative evaluation requires more complex modeling.

[en] Complete text of publication follows. One of the best preserved terrestrial records of past climate are in loess-palaeosol sequences around the world. Except classical Chinese loess, European sequences are widely used for palaeoenvironmental reconstructions. Low Danube loess deposits are part of the south-eastern loess cover, linking loess belt in Asia with Central European loess. Its magnetic properties have been extensively studied, putting emphasis on present continental conditions. In the present work, role of Black sea as climatic factor playing role in setting up rock magnetic properties of samples from Durankulak loess outcrop have been studied. Combined use of magnetic and DRS data show that magnetic enhancement of palaeosols is accompanied by an increase of hematite content, suggesting that pedogenic maghemite (magnetite) and hematite are simultaneously formed during warm interglacial periods. Comparison with data from a loess-palaeosol section in the countryside (away from maritime climates) suggests that more humid and warmer conditions favour faster growth of pedogenic Fe oxides towards stable SD magnetic grain sizes. Possible role of diagenetic effects will be discussed.

[en] Published in summary form only

[en] Complete text of publication follows. Studies of modern tropical soils have demonstrated that the relative abundance of pedogenic goethite and hematite is controlled by moisture availability. To evaluate the utility of a G/H ratio as a paleo-precipitation proxy, we conducted a rock-magnetic study of paleosol samples from a known paleo-environmental context. Goethite and hematite content of the studied samples has been estimated based on saturation IRM values of the corresponding magnetization components as identified by a statistical analysis of IRM acquisition curves. Independently, goethite contribution to the high coercivity fraction has been determined by the low-temperature cycling of the IRM. Both methods give identical estimates for the goethite content. The Neogene Siwalik strata of Pakistan are composed of several thousand meters of stacked fluvial floodplain and channel deposits representing deposition by ancient river systems that drained the Himalaya Mountains and foothills. The Middle Miocene Chinji Formation, which is dominantly fine-grained, provides particularly good exposures of successive floodplain paleosols. G/H ratios of samples collected over 100's of meters along a lateral transect in a single Chinji Fm. paleosol show a good correlation (R² =0.88) with δ¹⁸O of soil carbonate, indicating that the ratio can be effectively used as an indicator of moisture availability during pedogenesis. Based on lateral fluvial architecture and varying thickness of this paleosol, we can test the prediction that G/H ratios are lower on topographic highs compared with G/H ratios from topographic lows. Siwalik paleosols affected by fire show a significant change in the high coercivity fraction. In contrast to unbaked samples, burned paleosols lack the goethite component, while the hematite component shows a ∼ 350 mT increase in the mean coercivity value. Evidence for paleo-fires as well as the G/H ratios and their correlation with soil carbonate δ¹⁸O provide new insights on varying environmental conditions that characterized the Miocene sub-Himalayan alluvial plains.

No abstract available

[en] Highlights: • Establishing biomass briquette as a substitute to coal. • First ever usage of biomass briquettes as a reductant of iron ore. • Iron recovery from iron ore slime using reduction roasting and magnetic separation. • Product with ∼64–65% Fe at a weight recovery ∼63–64% from a slime of 56.2% Fe. - Abstract: The present study explores the application of biomass briquette, produced from the unutilized vegetative remnants, as an alternative reductant for the reduction roasting-magnetic separation of an iron ore slime sample assaying 56.2% Fe. The X-Ray Diffraction (XRD) studies indicated tridymite and quartz to be the only crystalline mineral phases present in the biomass briquettes while the Fourier Transform Infra Red (FTIR) spectra identified several organic functional groups representing the biomass. Iron ore concentrates with ∼65% Fe and ∼64% weight recovery were obtained with reduction conditions such as temperature: 650–750 °C, reductant to feed ratio: 0.15, reduction time: 30–45 min and reductant size: −3+1 mm. The analysis of the statistically designed experiments suggested that temperature is the most crucial factor followed by time, reductant to feed ratio and reductant size. Magnetite and hematite were found to be the only major phases present in the magnetic fractions produced from roasting at the optimum conditions. Many feebly magnetic phases like wustite, fayalite and clinoferrosilite appeared at higher temperature and reductant to feed ratios, which was confirmed by XRD, reflected light microscopy and quantitative mineralogical analysis.

[en] In the present work, hematite iron oxide nano-particles are synthesized through a facile wet chemical precipitation route. The phase formation behavior and microstructure evolution of the synthesized nano-particles are studied using infrared spectroscopy in conjunction with x-ray diffraction analyses and electron microscopy. Chemi-resistive type hydrogen sensing characteristics (e.g. response %, response time, recovery time) of hematite iron oxide nano-particulate sensing element are evaluated using an automated, dynamic flow gas sensing measurement set-up. The sensing characteristics are measured by varying the operating temperature (275–350 °C) of the sensor and concentration of hydrogen (250–1660 ppm). From the operating temperature dependence of response and recovery times, we have estimated the respective activation energies for response and recovery processes. (paper)

[en] The paper presents the data the composition of modern composite building materials including materials which in addition to high physical-mechanical have radio-protective properties. The article presents infrared researches and differential thermal data of fine-grained magnetite and hematite beneficiated iron-ore concentrates. The choice of the most suitable filling for new composite radio-protective building material engineering and development was made basing on the magnetite and hematite data presented in the paper. (paper)