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Objective To evaluate the outcome of patients with ROCM (Rhino-orbito-cerebral mucormycosis) following their medical and surgical management. Materials and methods It is a prognostic study based in a tertiary care center in North-Western India. Patients who developed ROCM post COVID-19 infection from 1st September 2020 to 30th June 2021 were included in this study. Surgical debridement and administration of antifungal therapy was done for the post-COVID-19 ROCM patients. Disease progression and survival was studied up to 5 months of follow-up in the second wave. Results A total of 145 ROCM patients were included. The mean age at presentation, male: female ratio was 48.2 years and 2:1 respectively. As per our proposed new staging system and treatment strategy, the majority of patients belonged to stage II (31.72%) and stage III (31.03%). On a follow-up period of 5 months, 26 (18%) patients have lost their life and rest of the patients are on strict follow-up. Conclusion ROCM is an extremely aggressive fungal infection which rapidly became an epidemic following the COVID-19 pandemic. The diverse and unique presentation led us to evolve a new strategy to classify and manage these patients.

Boldine, a bioactive compound, has been reported to be neuroprotective, but its effect on learning and memory has not been explored. So, the present study was aimed to study the effect of boldine on the learning and memory of the Swiss albino male young and aged mice. Boldine (1.5, 3 and 6mg/kg, po) and physostigmine salicylate (0.1mg/kg, ip) were administered to separate groups of mice for 7 successive days. Morris water maze was utilized as a behavioural model to study the effect of drugs on learning and memory of mice. Boldine and physostigmine significantly improved learning and memory of young as well as aged mice, as indicated by decrease in escape latency time during training session and increase in time spent in target quadrant during retrieval session. No significant effect on locomotor activities of mice was observed due to drug treatments. Memory-enhancing activity of boldine (3mg/kg) was found to be comparable to physostigmine. Boldine significantly reversed scopolamine-, sodium nitrite- and aging-induced amnesia in mice. Moreover, boldine attenuated oxidative stress, as shown by a significant decrease in brain malondialdehyde as well as brain nitrite levels and a significant increase in brain GSH level of young as well as aged mice. Brain acetylcholinesterase activity was also significantly inhibited by boldine in young as well as aged mice. In conclusion boldine administered for 7 successive days exhibited significant improvement of learning and memory of young and aged mice possibly through inhibition of brain acetylcholinesterase activity and alleviation of brain oxidative stress.

ZrSBA-15 support with Si/Zr = 20 containing majority of Zr in framework positions is synthesized by direct addition of Zr to the synthetic mixture. Various catalysts containing 2–12 molybdenum loading were prepared by incipient wetness impregnation. Using 8 wt% Mo catalysts Co and Ni promoted catalysts were prepared with 1–5 wt% promoter loading. All the Mo, CoMo, NiMo catalysts were characterized by N2 adsorption–desorption, low angle and wide angle XRD, temperature programmed reduction (TPR) and oxygen chemisorption on sulfide catalysts. The catalytic activities for thiophene HDS, cyclohexene HYD were evaluated on sulfide catalysts at 400 °C. The oxygen uptakes and catalytic activities for HDS and HYD passed through a maximum at 8 wt% loading. The H2/Mo ratios obtained as a function of Mo loading also passed through a maximum at the same temperature. The promoted catalyst showed maximum activity at 3 wt% loading for both the functionalities. These results will be discussed in the light of characterization results in terms of reducibility, dispersion and anion vacancy variation with Mo and promoter loading.

SBA-15-supported nickel phosphides with a Ni/P atomic ratio of 2 and 0.5 were prepared by temperature programmed reduction method (TPR). The phase purity and structural/surface properties were studied by X-ray diffraction and N2 sorption measurements respectively. X-ray diffraction (XRD) analysis of the passivated catalysts confirmed the presence of Ni12P5 and Ni2P phases in catalysts prepared from oxidic precursors. Supports and catalysts were thoroughly characterized using other techniques such as SEM, EDAX, and TEM. Results from low angle XRD measurements confirmed the presence of hexagonally ordered mesoporous structure in SBA-15 material. Hydrotreating experiments were conducted under industrial conditions using coker light gas oil (CLGO) as feed which contains 2439 ppm nitrogen 23,420 ppm sulfur respectively. The activity results show that SBA-15 supported NixPy catalysts show higher catalytic activities compared to reference NiMo/SBA-15 and NiMo/γ-Al2O3 catalysts under similar reaction conditions. This higher catalytic activity of NixPy/SBA-15 is due to the structure and surface chemical properties of this phase which is resistant to sulfur poisoning. It was also found that the Ni/P ratio had a profound effect on the active structure and hydroprocessing behavior of the NixPy/SBA-15 catalysts. The HDS and HDN conversions was found in the following order NixPy/SBA-15 (0.5) > NixPy/SBA-15 (2.0) > NiMo/SBA-15 > NiMo/γ-Al2O3. The NixPy/SBA-15 (0.5) catalyst showed higher HDS and HDN activities compared with NixPy/SBA-15 (2.0) catalyst which has lower P content. The higher amount of P content in NixPy/SBA-15 (0.5) catalyst modifies the nature of the nickel in that catalyst and increased the amount of octahedral nickel species and causes higher hydrotreating activity.

In the present work, a series of FeW/SBA-15 catalysts were prepared and screened for their hydrodesulfurization and hydrodenitrogenation activities using bitumen-derived heavy gas oil from Athabasca. A systematic process optimization study has been conducted to investigate the optimum process conditions required to evaluate kinetic parameters for these reactions. Catalyst metal loadings were varied from 0 to 5 and 15 to 45 wt.% for Fe and W, respectively; resulting in an optimum catalyst (Cat-5) with metal loadings of 3.0 and 30.0 wt.% for Fe and W, respectively. Several techniques were employed to characterize the prepared catalysts and activity results have been correlated with that obtained from characterization. Hydrotreating experiments were performed in a continuous flow micro trickle-bed reactor at the temperatures, pressures, and LHSVs of 633–693 °K, 7.6–9.6 MPa, and 0.5–2 h −1 , respectively, with H 2 flow rate and catalyst weight maintained constant at 50 mL/min and 1.5 g, respectively, in all cases. Three kinetic models were applied to fit experimental data obtained from HDS and HDN reaction studies evaluated within temperature range of 633–693 °K. The optimum operating conditions for maximum sulfur and nitrogen conversions occurred at temperature, pressure, and LHSV of 673 °K, 8.8 MPa, and 1 h −1 , respectively. Experimental data fitted with the Power Law model yielded reaction orders of 2.0 and 1.5 for HDS and HDN reactions, respectively; and activation energies of 129.6 kJ/mol and 150.6 kJ/mol, respectively. By fitting a modified power law model (Multi-parameter model) to the kinetic data yielded hydrodesulfurization (HDS) and hydrotreating (HDN) reactions orders of 2.2 and 1.8, with respective activation energies of 126.7 kJ/mol and 118.8 kJ/mol.

Well ordered FSM-16 mesoporous material was synthesized by using established procedures. Mo, CoMo, NiMo catalysts were prepared using this FSM-16 mesoporous material as support. The support and the catalysts were characterized by XRD, Transmission electron microscopy (TEM) pore size distribution measurements. The XRD, TEM and pore size distributions indicated that the ordered mesoporous structure is obtained and retained after Mo and Co(Ni) additions. The wide angle XRD measurement indicated that molybdenum is highly dispersed up to 12 wt.% Mo loading. The surface area analysis indicated that molybdenum is highly dispersed as monolayer 12 wt.% Mo zero point charge (ZPC) and XRD measurements confirmed the same. The oxygen chemisorption measurements indicated that the higher dispersion in the oxide state is carried into sulfided state also. The thiophene HDS, cyclohexene hydrogenation and cumene cracking activities all showed that maximum activity is obtained at 12 wt.% Mo loading. Excellent correlations are obtained between oxygen uptakes and catalytic activities. These studies indicated that MoS2 phase has significant cracking functionality. The correlations with catalytic functionalities are discussed in the light of characterization results.

Benzaldehyde is an important chemical and has tremendous application in cosmetics, perfumery, food, dyestuff, agrochemical and pharmaceutical industries. In the present investigation, threefold increase in oxidative property of mesoporous Ti-SBA-15 was observed by treatment with chlorosulfonic acid. Physio-chemical properties of this catalyst were analyzed by BET surface area, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), FTIR, and NH3-temperature programmed desorption (TPD) techniques. The super acidic nature of the catalyst is shown by NH3-TPD profile. Enhanced acidity of the catalyst increases benzyl alcohol conversion from 20 to 62% without affecting benzaldehyde selectivity (95%).

SBA-15 supported NiMo hydrotreating catalysts with different EDTA/Ni molar ratio were prepared by incipient wetness impregnation method. Hydrotreating activities of these catalysts were studied with Athabasca bitumen derived light gas oil and comparison was done with NiMo/SBA-15 and NiMo/γ-Al2O3 catalysts. A beneficial effect of chelating ligand was seen in hydrotreating activity and 28% increase in HDS of LGO was found as compared to NiMo/γ-Al2O3 in the case of EDTA/Ni molar ratio 4. Detailed mechanistic aspect of interaction between support – EDTA (ethylene diamine tetraacetic acid), EDTA-metallic species, support – metal, metallic species – metallic species at different reaction conditions is studied at different process parameters by using different characterization techniques such as X-ray absorption near-edge structure (XANES), Fourier transform infrared spectroscopy (FTIR), HRTEM, XRD, Raman, temperature programmed reduction (TPR), ICP-MS, CO chemisorption and N2 adsorption. A detailed scheme has been developed to explain the behavior of chelating agent in mesoporous SBA-15 supported catalysts. HRTEM results explain the high dispersion of Ni and MoS2 active phases in sulfided state even though big crystallite of MoO3 was seen in oxide state characterized by XRD and Raman spectra which explains role of EDTA in redistribution of active phases during sulfidation. XANES technique is used as predominant method for atomic level study of various structural changes in sulfided and oxide catalysts to find out the appropriate mechanism of the reaction. Characterization by XANES reveals that the presence of chelating agent delayed Ni2+ sulfidation which is main cause of improvement in HDS and HDN activity of the catalysts prepared in presence of organic chelates. Nickel sulfidation starts only when the EDTA–Ni complex decomposes and released nickel atoms move to the reactive edges of the MoS2 to form a finely dispersed sulfide Ni Mo S type II active phase.

TiSBA-15 with high surface area and large pore diameter with variable Si/Ti molar ratios of 20, 40, and 80 were synthesized and used as supports for NiMo catalysts. TiSBA-15 supports and NiMo/TiSBA-15 catalysts were extensively characterized by using XRD, N 2 adsorption analysis, FT-IR, Py-FTIR, Raman, TPR, SEM and TEM techniques. Results from XRD and IR measurements confirm the hexagonally ordered mesoporous structure and incorporation of Ti into the framework of SBA-15 support, respectively. TPR analysis confirmed that Ti incorporation resulted in better dispersion and more homogeneous distribution of octahedral Ni and Mo species on the support compared to NiMo/SBA-15. Hydrotreating experiments were conducted using coker light gas oil (KLGO) under industrial conditions of temperature, pressure, LHSV, and gas to oil ratio of 330–370 °C, 8.8 MPa, 2 h −1 , and 600 mL/mL, respectively. NiMo/TiSBA-15 catalysts showed very high catalytic activities of hydrodesulfurization and hydrodenitrogenation of KLGO than the NiMo catalysts prepared by using SBA-15 and γ-Al 2 O 3 as support.

Mesostructured alumino-silcate (MAS) materials were synthesized from ZSM-5 nano-clusters and used as catalysts supports for the hydrotreatment of a model compound and real feed stock. Supports and catalysts were thoroughly characterized by using XRD, N 2 adsorption analysis, FT-IR, 27 Al MAS NMR, Raman, EXAFS and HRTEM techniques. The alumino-silicate materials exhibited different acid strength and textural properties depending on the duration of hydrothermal treatment of the zeolite seeds. Materials synthesized with low seeding time of 4 h showed properties similar to Al-SBA-15 prepared using the direct synthesis route, whereas material with high seeding time ( t seed = 24 h) resembled ZSM-5. The EXAFS study of the sulfided catalysts revealed that sulfidation was highest in the NiMo catalyst supported on mesoporous alumino-silicate synthesized from ZSM-5 seeds with 16 h of hydrothermal treatment (MAS-16). Hydrotreating experiments were conducted using model compound (DBT) at 325 °C and 600 psi as well as real feed stock (Coker light gas oil) at industrial conditions. Catalytic activity in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) was found to be maximum for this particular catalyst (MAS-16). The same catalyst also gave higher hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) conversion than NiMo/γ Al 2 O 3 in the hydrotreating of Light Gas Oil.

SBA-15 with pore diameter greater than 10 nm was synthesized by varying the synthesis parameters and adding swelling agent hexane and inorganic salt ammonium fluoride. Direct and post synthesis modification methods were employed to incorporate aluminum in the framework of SBA-15. In the direct synthesis approach, the highest pore diameter achieved was limited to 7 nm, but post synthesis method was employed successfully to achieve high pore diameter catalysts. The pore structure of the synthesized SBA-15 did not collapse until 13 nm of pore diameter as confirmed from the small angle XRD and TEM. The prepared Ni–Mo catalysts with different pore diameters were screened for hydrotreating of heavy gas oil (HGO) in a trickle bed continuous reactor. The catalyst with 13 nm pore diameter gave highest conversion compared to other catalysts.

This work focuses on utilizing mesoporous SBA-15 materials of different pore diameters as potential hydrotreating catalyst supports for heavy gas oil (HGO). Hexane was used as swelling agent for the preparation of variable pore diameter SBA-15 materials. Four kinds of SBA-15 supported FeW catalysts with different pore diameters in the range of 5–20 nm were prepared and designated as Cats-A to D. The aqueous co-impregnation technique was employed for preparation of the catalysts. The supports were characterized by several techniques including X-ray powder diffraction (XRD) and N2 adsorption–desorption isotherms. The SBA-15 supported FeW catalysts were characterized by ICP-MS, BET surface area analysis, powder XRD, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and CO chemisorption. Results from XRD profiles, TEM images, and N2 adsorption–desorption isotherms confirmed the presence of highly ordered two-dimensional hexagonal structure with cylindrical arrays of pores. The structural integrity of the samples was preserved even after loading of 2 wt.% Fe and 15 wt.% W. Hydrotreating experiments were conducted using bitumen derived heavy gas oil under industrial conditions of temperature, pressure, LHSV, and gas to oil ratio of 375–400 °C, 8.8 MPa, 1 h−1, and 600 mL/mL, respectively. The SBA-15 supported catalyst with pore diameter of 10 nm (Cat-B) was the best among the supports studied for FeW catalysts, probably due to sufficient mass transfer of reactant liquids and gases through the catalyst's pores while still maintaining a high surface area necessary for metal dispersion.

In the present investigation, Ti–HMS materials with variable Si/Ti molar ratios of 20, 40, and 80 were synthesized and employed as supports for Ni-promoted 12-molybdophosphoric acid (NiPMo) catalysts. The effect of the Ti ions and the immobilization of 12-molybdophosphoric acids on mesoporous materials were studied. Supports and catalysts were thoroughly characterized by using XRD, N 2 adsorption analysis, FT-IR, Raman, TPR, DRIFT, SEM and TEM techniques. Results from XRD and IR measurements confirm the hexagonally ordered mesoporous structure and incorporation of Ti into the HMS support, respectively. It was found that incorporation of Ti and presence of HPA into the HMS structure increased the reducibility of the catalysts. Hydrotreating experiments were conducted using coker light gas oil under industrial conditions of temperature, pressure, LHSV, and gas to oil ratio of 330–370 °C, 8.8 MPa, 1 h −1 , and 600 mL/mL, respectively. It was found that NiPMo catalysts prepared from heteropolyacids showed better performance in HDS and HDN of coker light gas oil (CLGO) than the NiMo catalysts prepared by conventional method using ammonium hepta molybdate (AHM) as Mo source.

KIT-6 silica with well-ordered 3-D mesoporosity was developed as support for Mo, CoMo and NiMo catalysts. TEM and low-angle XRD analyses were used to ensure that the cubic Ia3d mesostructure is stable after Mo and promoter incorporation. The wide-angle XRD (as well O2-chemisorption analysis) was used to verify MoO3 (and MoS2) dispersion, with crystallite size

SBA-15 containing various amount (10–50 wt.%) of highly dispersed ZrO 2 is prepared using urea hydrolysis method. The sulfated zirconia (ZrO 2 ) in SBA-15 catalysts were prepared using these materials. The materials were characterized by XRD, BET surface area, TEM, TGA, acidity measurements using in situ IR pyridine adsorption, sulfate content and catalytic activities were studied for cumene cracking and esterification of cyclohexanol. The Bronsted acidity, catalytic activity for cumene cracking and esterification and sulfate content were found to pass through a maxima where ZrO 2 loading is 35 wt.%. The 35SZ-SBA catalysts exhibited 6.4 times higher activity for cumene cracking compared to the bulk SZ catalysts. The relationship between acidity, sulfate content and catalytic activity are discussed in the light of existing knowledge on sulfated zirconia.

Al-SBA-15 of varying Si/Al ratios in the range 11.4–78.4 was synthesized using tri-block copolymer P123. The calcined materials were examined by XRD, pore size distribution, surface area, 27 Al NMR spectroscopy. The acidity and acid strength distribution were studied using microcalorimetric adsorption of NH 3 . The acidic properties were also examined by cumene cracking reaction as a function of Si/Al ratios. Systematic variation of acidity and activity was observed as a function of Si/Al ratio. The initial heats of NH 3 adsorption correlated well with activity indicate that acid sites with Δ H > 100 kJ/mole is responsible for cumene cracking activity. Linear correlations were obtained with total acidity and cumene cracking activities. The tetrahedral aluminum was found to be responsible for the observed acidities and catalytic activities.

SBA-15 and ZrO 2 (10–50 wt.%) containing SBA-15 mesoporous materials were prepared by direct and post-synthesis methods. Characterization using low angle XRD, pore size distribution, CO 2 chemisorption indicate that hexagonal mesoporous structure is retained even after ZrO 2 addition (25 wt.%). Mo, CoMo and NiMo catalysts prepared using these supports were examined by XRD, oxygen chemisorption, temperature programmed reduction (TPR). The catalysts were tested for hydrodesulfurization (HDS) of thiophene and hydrogenation (HYD) of cyclohexene. HDS of thiophene for 8%Mo, 3%Co8%Mo, and 3%Ni8%Mo increases with increasing ZrO 2 loading in SBA-15 up to 25 wt.%. Oxygen chemisorption and TPR hydrogen consumption indicated that the molybdenum dispersion and anion vacancies, and catalytic activities are significantly influenced by ZrO 2 content in Zr-SBA-15. A comparison indicated that TiO 2 -SBA-15, ZrO 2 -SBA-15 supported CoMo catalysts show higher activities for hydrodesulfurization.

SBA-15 and Al-SBA-15 of varying Si/Al ratios (10–40) were synthesized by well-known procedures. Characterization using XRD, pore size distribution, 27 Al NMR confirmed that hexagonal mesoporous structure is obtained and majority of Al is in tetrahedral positions. Mo, CoMo and NiMo catalysts prepared using these supports were examined by XRD, oxygen uptakes in sulfided state and temperature programmed reduction (TPR). The catalysts were tested for hydrodesulfurization (HDS) of thiophene and hydrogenation of cyclohexene. Systematic variation of oxygen chemisorption and catalytic activities were observed as a function of Si/Al ratio. The systematic variation of activities, oxygen chemisorption and TPR hydrogen consumption of Mo indicated that the molybdenum dispersion and anion vacancies, and catalytic activities are significantly influenced by support Al content. Compared to SBA-15, Al-SBA-15 supported Mo, CoMo and NiMo catalysts show outstanding activities for hydrogenation.