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Gold-containing ore processing technology has been developed by using chemical, X-ray phase, mineralogical, X-ray fluorescence analyses. The results of experiments on the gold recovery from a concentrate with a particle size of 10 and 4 µm are presented, including options for direct cyanidation without preliminary oxygen oxidation, as well as with the use of preliminary oxidation of Trichloroisocyanuric acid (TCCA) and Sulfanol surfactant (SAS). It was found that the test sample contains 24.74 g/t Au; 11.66% S; 18.51% Fe. The content of sulfide minerals is 36.1%, the main sulfides are arsenopyrite (25.4%) and pyrite (10.7%). Microscopic examination of the combined gravity-flotation concentrate revealed ultrafine, fine and visible gold dust particles both in free form and in aggregations with waste rock. The particle size of Au in the product varies from 0.5 to 18.8 μm. 77.12% of gold is recovered from concentrate of 10 μm by direct cyanidation. “Sulfanol” was used to recover 83.71% of gold. Pre-treatment with TCCA yielded 85.61% of gold. Recovery of gold from the 4 μm concentrate was 75.38% for direct cyanidation, 78.79% for cyanidation with Sulfanol surfactant, 76.52% for cyanidation with TCCA.

In this work, the novel utilisation of customised double- and triple-tail sodium bis(3,5,5-trimethyl-1-hexyl) sulphosuccinate (AOT4) and sodium 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-silphonate (TC14) surfactants to assist the direct graphene oxide (GO) synthesis via electrochemical exfoliation utilising dimethylacetamide (DMAc) as a solvent were investigated. The synthesised DMAc-based GO and titanium dioxide (TiO2) nanoparticles were then used to fabricate polyvinylidene fluoride (PVDF)-based nanofiltration (NF) membranes by the non-solvent-induced phase separation method. The incorporation of GO and TiO2 as hydrophilic nanoparticles were to enhance membrane hydrophilicity. The utilisation of higher surfactants’ tail number obviously alters the fabricated membrane’s morphology which further affects its performance for dye rejection and antifouling ability. Higher surfactants’ tail number resulted in higher oxidation process which then provided more interaction between the GO and PVDF. Based on the dead-end cell measurement, PVDF/TC14-GO/TiO2 presented a slightly higher dye rejection efficiency of 92.61% as compared to PVDF/AOT4-GO/TiO2 membrane (92.39%). However, PVDF/TC14-GO/TiO2 possessed three times higher water permeability (48.968 L/m2 h MPa) than PVDF/AOT4-GO/TiO2 (16.533 L/m2 h MPa) and also higher hydrophilicity as presented by lower contact angle (65.4 ± 0.17°). This confirmed that higher surfactants’ tail number improved the fabricated membrane’s performance. Both fabricated membranes also exhibited high flux recovery ratio (FRR) ( $$>$$ 100%) which indicated better antifouling properties.

This research is to study the possibility of fabricated zinc borosilicate glass doped with neodymium trioxide (ZnO-B2O3-SiO2:Nd2O3) to be a new material candidate for TLD. TGA analysis is an analytical technique used to determine a thermal stability of materials and its fraction of volatile components by monitoring rate heat flow to and from a sample and the weight changes, as temperature is changed at a constant rate. Data obtained is used to determine temperature of transitions and melting points of substances. Glass Transition Temperature (Tg) for the glass TLD sample produced obtains are between 369.01 °C - 371.74 °C and maximum annealing and reading temperature are set to be 350 °C that are below the minimum Tg values. X-Ray Diffraction (XRD) analysis has proven the samples fabricated are amorphous. Effective atomic numbers (Zeff) are in the range of 20.44-21.60. Glass TLD samples showed good linearity with TL response and faced 45.22%-59.37% fading after 30 days. Glass TLD samples also have been tested for their reproducibility ability for 6 cycles of annealing, irradiate and reading process and the reading showed a small range of different.

New type plasmonic sensitizer, titanium nanoparticles (Ti NPs) shown potential in enhancing photoluminescence of rare-earth ions (REIs) as doped into magnesium zinc-sulfophosphate (MZS) glass for optical to optic application. Here, neodymium ions (Nd3+)-doped MZS glass with Ti NPs inclusion gone heat treatment (HT) at 450°C for 6 and 12 hours in order to tune the NPs size and tailor their plasmonic strength. The sample was characterized using X-ray diffractometer (XRD), high-resolution transmission electron microscope (HRTEM), and photoluminescence (PL) spectrometer. Heat treatment (HT) grows Ti NPs with a mean size ≈ 16 nm. The SPR bands are probed around 585and 739 nm. The SPR band intensities change with HT duration. The NIR PL bands were perceived around 878 nm, 1050 nm and 1322 nm corresponding to 4F3/2→4I9/2, 4F3/2→4I11/2 and 4F3/2→4I13/2 transitions, accordingly. The PL transition 4F3/2→4I9/2 (878 nm) and 4F3/2→4I13/2 (1322 nm) is enhanced about 1.44 and 1.52 times respectively, after 12 hours HT. The results show that HT enhances PL through SPR amplification. These findings may be useful in developing solid-state lasers and optical materials.

In the present work, the optical properties and gamma-ray shielding properties of 70[xTeO2 + (1−x)B2O3] + 15Na2O + 15K2O glasses have been investigated. The optical band gap ( E o p t ) showed an initial decrease for x ≤ 10 mol% and then increased for x >10 mol%, which is suggested to be related to the changes in concentration of non-bridging oxygen (NBO). Urbach energy ( E u ) behaves inversely with E o p t . Within the same region, refractive index (n) also exhibited an off-trend pattern that signified polarizability difference led by alteration in bridging oxygen and NBO concentration. The mass attenuation coefficient (MAC) derived from interpolation of EPICS2017 in ENDF/B-VIII were in good agreement with generated values of XCOM and showed a decreasing trend with increasing gamma photon energy from 59.5 keV to 1333 keV. The linear attenuation coefficient (LAC) also showed a decreasing trend with the increase in energies from 59.5 to 1333 keV, which indicates that the prepared TeO2-B2O3-Na2O-K2O glasses can effectively shield the low energy photons, while this ability to shield the photons becomes weaker with increasing energy. The results revealed that the sample with no TeO2 has a relatively higher mean free path (MFP) compared to other samples, and the addition of TeO2 highly affects the MFP values. Thus, the glass with no TeO2 requires a much higher thickness than the remaining glasses to attenuate the photons and to provide sufficient protection from radiation.

In this work, the novel direct synthesis method of dimethylacetamide-based graphene oxide (GO) was performed through electrochemical exfoliation assisted by commercially available single-tail sodium dodecyl sulphate (SDS) surfactant. Then, the synthesised GO (SDS–GO) was incorporated into polyvinylidene fluoride (PVDF) solution to produce a nanofiltration (NF) membrane through the phase immersion method. The addition of GO into the preparation of membrane solution alters the membrane morphology and improves the hydrophilicity. TiO2 was also used as an additive for the NF membrane fabrication to further increase the membrane hydrophilicity. The fabricated PVDF/SDS–GO/TiO2 and PVDF/SDS–GO NF membranes were compared with pure PVDF membrane. Then, the fabricated NF membranes were tested for methylene blue (MB) rejection with 10 ppm MB concentration. On the basis of the dead-end cell measurement operated at the pressure of 2 bar, the PVDF/SDS–GO/TiO2 presents high MB rejection (92.76%) and the highest dye flux (7.770 L/m2 h). This dye flux value was sevenfold higher than that of pure PVDF membrane (1.146 L/m2 h) which was due to the utilisation of both GO and TiO2 that improved the membrane hydrophilicity as indicated by the lowest contact angle (64.0 ± 0.11°). High porosity (57.46%) also resulted in the highest water permeability (4.187 L/m2 h bar) of the PVDF/SDS–GO/TiO2 NF membrane.