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[Display omitted] • The HRBF implicit function is used to construct a three-dimensional ore body model. • Automatic implicit conversion from existing three-dimensional ore body models is proposed. • Automatic ore body model partial updating from new boreholes and excavation data is demonstrated. In the mine production process, pre-established geological models should be updated in a timely manner based on new geologic and mining data. Three-dimensional (3D) geological models of different engineering schedules can effectively visualize the spatial distribution of the ore body in real time, displaying changes in its structure and occurrence in a timely manner and thereby providing geological guidance for overall project designs. In this paper, we propose an automatic update algorithm for 3D geological body models based on an implicit function and geostatistics. With this algorithm, the ore body model can be rapidly and automatically updated according to the original ore body exploration/mining data. The effectiveness of this algorithm was tested in several cases, and the results were compared with those of traditional ore body modelling methods. The results show that the proposed ore body model construction and updating algorithm is fast, effective, and automatic and that the resulting models are smooth and free of topological errors. In addition, this method considers the existing models and incremental data, automatically and quickly extracts constraint data from incremental data, reasonably integrates or transforms existing models to make full use of them, and builds and updates more reasonable and smooth ore body entity and grade models. [ABSTRACT FROM AUTHOR]

A colloidal templating method was applied to fabricate a composite of three-dimensionally ordered macroporous carbon-encapsulated Ni nanoparticles (3DOM Ni@C) by using citric acid and nickel nitrate as raw materials and polymethyl methacrylate (PMMA) microspheres as template. The products were characterized by XRD, TEM, ICP, TG-DTA, XPS, N 2 adsorption-desorption and magnetic measurement. In 3DOM Ni@C, metallic Ni nanoparticles (4.0–7.0 nm) were tightly wrapped by multilayer graphitized carbon with a highly ordered three-dimensionally arrangement in a large scale. While sufficient citric acid was supplied, multilayer carbon nanotubes were formed with the Ni nanoparticles at one end of them. Cu-supported 3DOM Ni@C materials were found to be highly efficient for catalyzing the reduction of 4-nitrophenol (4-NP). The rate constant reached 0.0512 s−1 over 3.5%Cu/3DOM Ni@C-1. Importantly, the catalyst showed good recycling performance due to its magnetically recoverable property and the improved stability brought by the encapsulated structure. [Display omitted] • A simple method for the preparation of Ni@C composite was developed. • Ni nanoparticles were tightly wrapped by multilayer graphitized carbon with a 3DOM framework. • 3DOM Ni@C was magnetically recoverable with improved stability for liquid-phase reaction. • High activity and good recycling performance for 4-NP reduction was obtained. [ABSTRACT FROM AUTHOR]

• A linear closed-form model is proposed for quasi-brittle fracture of sandstone. • 95 sandstone specimens with volume ratio close to 1000 were tested and analyzed. • One normal distribution considering scatters/reliability applies to all results. • The closed-form solution is a predictive model more suitable for design analysis. • Statistical analysis of discrete cracking removes the need of curve-fitting. Quasi-brittle fracture properties of a medium-grain sandstone with an average grain size G around 0.3–0.4 mm were investigated under three-point-bending (3-p-b) conditions. In total, 95 specimens were tested with the beam width W varying from 10 to 300 mm, or the specimen-size/grain-size ratio from 30 to 900. 45 medium-sized specimens (W = 30, 60, 100 mm) were tested first to determine the tensile strength f t , which was then used as a reference for tests of 8 large notched specimens (W = 300 mm) and 42 small un-notched specimens (W = 10 mm). Statistical fracture modelling, based on normal distributions and the characteristic microstructure measurement (the average grain size G in this study), was used to quantify the quasi-stable fictitious crack growth Δ a fic at the peak load P max and the characteristic crack length a ch * defined by the bulk toughness and strength properties. The statistics-assisted modelling has changed the previous curve-fitting boundary effect model (BEM) to a predictive closed-form solution, providing a useful option when large scatters in experimental data and reliability in design need to be focused. The well-known size effect law (SEL) proposed for geometrically similar specimens was also used to fit the sandstone results, and compared with the closed-form BEM with built-in statistical functions. Applications of SEL and BEM and their key differences were explained. [ABSTRACT FROM AUTHOR]

Towards the malignant impact of red mud on the environment and water pollution caused by organic dyes, affluent residual iron ions in red mud are recovered and converted into functional hierarchical porous α-Fe 2 O 3 microspheres (HP α-Fe 2 O 3 MSs) comprising nanosheets (S BET : 78.75 m2 g−1, pore volume: 0.35 cm3 g−1, mean pore diameter: 15.92 nm) via a facile hydrothermal route (180 °C, 12.0 h), with the presence of urea and CTAB. When employed as the adsorbents for Congo red (CR) in simulated wastewater, the adsorption isotherm is well fitted with Langmuir isotherm model, and the corresponding maximum adsorption capacity is determined as 342.57 mg g−1, superior to that of most referred adsorbents in literatures. Meanwhile, the adsorption kinetic data can be well interpretated via the pseudo-second-order and intra-particle diffusion models. Moreover, the red mud derived HP α-Fe 2 O 3 MSs can be easily regenerated and reused with satisfactory chemical, morphological and structural stability. Affluent residual iron in red mud is extracted for the facile green hydrothermal synthesis of the hierarchical porous α-Fe 2 O 3 microspheres as efficient adsorbents for removal of Congo red, with excellent adsorption capacity and satisfactory recycling performance. Image 1 • Abundant iron in red mud is hydrothermally converted into hierarchical porous α-Fe 2 O 3 microspheres. • Adsorption isotherm can be well fitted with Langmuir isotherm model, with the q m determined as 342.57 mg g−1. • Microspheres can be easily regenerated and reused with satisfactory chemical, morphological and structural stability. • Major phase of the quasi amorphous iron-bearing room temperature precipitate is determined as Fe(OH) 3. • Adsorption kinetic data can be well interpretated via the pseudo-second-order and intra-particle diffusion models. [ABSTRACT FROM AUTHOR]

In this study, a one-part alkali-activated slag (AAS) composed of ground-granulated blast furnace slag, desulfurized gypsum, and hydrated lime is proposed as alternative to cement for the production of cemented fine tailings backfill (CFTB), which is an environmentally friendly binder consisting of 93.72 wt.% industrial solid waste. Results show that AAS with 67.83 wt.% slag, 25.92 wt.% desulfurized gypsum, and 6.25 wt.% hydrated lime yields the highest strength, which is 1.7-3.2 times that of ordinary Portland cement (OPC). Aside from calcium silicate hydrate gel, appreciable quantity of ettringite characterized by interlocking needles structure and high bound water is also produced during the AAS hydration process. In addition, the hydration heat of the AAS binder is 48% less than that of OPC. Moreover, CFTB made of AAS provides better workability than that of CFTB with OPC up to 20 h. The findings of this study will contribute to the production of more cost-effective, durable, and environmental-friendly cemented fine tailings backfill., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Oxygen evolution reaction (OER) is an important half-cell reaction of the electrical water splitting, for its high overpotential associated with sluggish OER kinetics. Therefore, it is critical to develop highly active and durable electrocatalysts to reduce the overpotential. Herein, ultra-small RuO 2 nanoparticles (NPs) supported on onion-like carbon (OLC) and carbon nanotube (CNT) are successfully synthesized by means of wet impregnation combined with annealing treatment, respectively. The microstructure characterization results showed OLC perfect graphitic carbon layer structure, and the RuO 2 NPs supported on the OLC possess larger particle size compared with the RuO 2 NPs supported on the CNT. Moreover, the electronic structure of Ru in RuO 2 /OLC was also optimized by the OLC support to be beneficial for the OER. The OER performance of the catalysts were investigated in 1 M KOH solution. The results show RuO 2 /OLC has a comparable OER activity to the commercial RuO 2 , but a significantly higher mass activity than the commercial RuO 2 . When compared with the RuO 2 /CNT, RuO 2 /OLC not only exhibits lower overpotential and Tafel slop, but also owns more active sites and higher TOF value, indicating the OLC support improved the OER activity of RuO 2 /OLC. Moreover, RuO 2 /OLC showed a superior stability compared with RuO 2 /CNT, which can be attributed to the excellent electrochemical oxidation-resistance of the OLC., (© 2022 IOP Publishing Ltd.)

Nickel phyllosilicates have attracted much attention owing to their potential applications in various fields. Herein, Ni 3 Si 4 O 10 (OH) 2 porous microspheres (NiSi-PMs) with a diameter of 1.2 to 3.2 μm were successfully fabricated via a urea-assisted hydrothermal method, and subsequently used to prepare supported Pd catalyst. Characterizations of the NiSi-PMs and the obtained catalyst, combined with the catalytic performance for the hydrogenation reaction, are presented and discussed. The BET surface area and pore volume of the NiSi-PMs were 196.2 m 2 g -1 and 0.70 cm 3 g -1 , respectively. The Pd/NiSi-PMs catalyst exhibited remarkable catalytic activity for the hydrogenation of styrene under mild conditions, with a turnover frequency of 5234 h -1 , and the catalyst was recovered and recycled for six consecutive cycles without any discernible loss of activity. H 2 -TPR and H 2 -TPD revealed that the activity of the catalysts was closely related to the adsorption property for hydrogen. The present Ni 3 Si 4 O 10 (OH) 2 supported Pd catalyst afforded a promising and competitive candidate for heterogeneous catalysis.