104 research outputs found
Investigating the performance of liquid and gas phase photoreactors for dynamic H2 production over bimetallic TiO2 and Ni2P dispersed MAX Ti3AlC2 monolithic nanocomposite under UV and visible light
No full textMonolithic TiO2 and Ni2P dispersed 2D Ti3AlC2 MAX nanocomposite synthesized by sol-gel method, was investigated for stimulating photocatalytic H2 production. The performance was tested in three types of photoreactors including visible light irradiated slurry, visible and UV light irradiated fixed-bed and monolith photoreactors in batch and continuous operation. Using TiO2/Ni2P/Ti3AlC2 highest H2 production was achieved, which was 1.13, 3.25 and 3.80 times higher compared to TiO2/Ti3AlC2, TiO2/Ni2P and TiO2 samples. Under visible irradiation, slurry photoreactor in continuous operation depicted the highest activity, which was 23.6 and 32.5 times increased than fixed bed and monolith photoreactor, respectively. Using monolith photoreactor operating under UV light, 136 times more H2 was produced compared to monolith photoreactor under visible-light and 1.73 times higher H2 production than slurry photoreactor under visible-light. This was evidently due to higher penetration power of UV irradiations inside the monolith channels. The light penetration was declined when monolith channel length was increased or visible light was employed. With increasing feed composition, H2 production was further increased due to efficient oxidation and reduction reactions. Fixed-bed and monolith photoreactors operating in batch mode under visible light revealed 301 and 20 times higher H2 production than fixed bed and monolith photoreactors under continuous operation. The highest photonic yield and space yield were achieved using slurry photoreactor, while under UV light illuminated monolith showed highest apparent photonic yield and space yield. The findings of this work would be helpful to maximize photocatalytic H2 generation performance using various reactors under visible and UV irradiations
Constructing Exfoliated, Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene-Dispersed, LaCoO<sub>3</sub> and pC<sub>3</sub>N<sub>4</sub>‑Based Nanocomposites with In Situ Grown Titania through Etching/Oxidation for Stimulating Solar H<sub>2</sub> Production
No full textThe use of a well-designed Ti3C2 MXene with
in situ embedded titania nanoparticles to construct a porous carbon
nitride (pCN)/LaCoO3 Z-scheme and S-scheme heterojunction
for stimulating solar hydrogen production has been explored. A novel
oxidized/etched approach was employed to produce MXene to maximize
charge separation in LaCoO3 perovskite-dispersed pCN. On
increasing the HF etching time from 24 to 48 h, the amount of titania
embedded over the MXene was increased, enabling 1.71 times more H2 evolution. More importantly, integrated etched/oxidized Ti3C2 nanoflowers showed more reaction area with enhanced
light absorption, which was more prominent with increased temperature.
The H2 evolution was significantly increased due to in
situ embedded TiO2. Comparatively, optimized 15Ti3C2Tx/pCN was found to be more
efficient at lower temperatures, which was further increased 7-fold
with a 10Ti3C2Tx/pCN-coupled LaCoO3 Z-scheme heterojunction. This obvious
enhancement was evidently due to utilizing the maximum redox potential
with good interface interaction among the components to promote charge
carrier separation. Among the sacrificial agents, TEOA was found to
be more promising, with 9.1 times more H2 production due
to its strong bond with amine-based pCN, which was further confirmed
by quantum analysis. In conclusion, the Z-scheme photosystem is promising
for efficient mobility and separation of charges and would also be
beneficial for other solar energy applications
Synergistically improved charge separation in bimetallic Co-La modified 3D g-C3N4 for enhanced photocatalytic H-2 production under UV-visible light
No full textSynergistically improved Lanthanum (La) and Cobalt (Co) co-modified g-C3N4 was synthesized for photocatalytic H2 generation from methanol-water mixture under UV–visible light irradiation. The g-C3N4 was synthesized by thermal polymerization and co-modification was carried out by wet impregnation method. Photocatalytic H2 production by Co2/La1-g-C3N4 was carried out in a slurry photoreactor with the highest H2 production of 250 µmol g-1h-1, which was 2.5, 1.35, and 1.25 times increased as compared to pristine g-C3N4, La1-g-C3N4, and Co2-g-C3N4, respectively. The enhanced activity can be associated with the synergistic effect for proficient charge separation due to electron trapping ability of Co and La, and C–H bond cleavage ability of La for enhanced oxidation. Among the sacrificial agents, highest H2 generation rate was observed with triethanolamine which generated 8.1, 3.6, 1.7, 2.4, and 4.2 times boosted H2 generation than water, ethanol, methanol, ethylene glycol, and glycerol, respectivel, because of the effectual binding of triethanolamine onto amine-containing g-C3N4. Moreover, it also depicted good photostability towards photocatalytic H2 generation. Therefore, Co and La co-modification was proved to be effective for efficient charge separation and reduction of charge carrier's recombination and would be beneficial for other solar energy applications
Constructing LaxCoyO3 Perovskite Anchored 3D gC3N4 Hollow Tube Heterojunction with Proficient Interface Charge Separation for Stimulating Photocatalytic H2 Production
No full textZosteriform idiopathic atrophoderma of Pasini and Pierini
No full textIdiopathic atrophoderma of Pasini and Pierini (IAPP) is a rare disease of unknown etiology characterized by well-defined atrophic plaques with a “cliff-drop” border that show no signs of inflammation, sclerosis, and induration. The trunk is most commonly affected site. It usually affects the body in a bilaterally symmetrical distribution, although asymmetric involvement has also been reported. Very few cases occurring in a zosteriform distribution have been reported. In this article, the author reports a rare case of IAPP in an 18-year-old male where the lesions are distributed in a zosteriform distribution on the trunk
Constructing LaxCoyO3 perovskite anchored 3D g-C3N4 hollow tube heterojunction with proficient interface charge separation for stimulating photocatalytic H2 production
No full textLaxCoyO3 perovskite dispersed porous three-dimensional (3D) g-C3N4 hollow nanotubes to construct a Z-scheme nanocomposite were successfully synthesized via a wet impregnation assisted ultrasonic approach and were used for photocatalytic H2 generation in a liquid phase slurry photoreactor under visible light. A rhombohedral distorted LaCoO3 perovskite with 1.70 eV narrow band gap for improved optical properties was synthesized by the combination of coprecipitation and a hydrothermal method. Additionally, two-dimensional (2D) porous g-C3N4 with advantageous structural features was synthesized by a novel, facile, and cost-effective technique depicting exposed active sites with improved charge mobility and charge separation. A Z-scheme heterojunction by a wet impregnation assisted ultrasonic technique was constructed by LaCoO3 anchored onto hollow tubular porous g-C3N4 formed after the curling of flaked nanosheets into hollow tubes. Highest amount of H2 was generated by 15 wt % of LaCoO3 dispersed over porous g-C3N4 in the nanocomposite. The Z-scheme heterojunction generated H2 (800 µmol g-1) which was 1.41 and 1.77 times higher than pristine porous g-C3N4 and pristine LaCoO3, respectively, contributing to the improved visible light absorption and reduced band gap, mass transfer, charge mobility, and charge separation. The nanocomposite showed stability over three consecutive cycles. Also, the nanocomposite generated CH4 by the simultaneous occurrence of water splitting and photoreforming. The apparent quantum efficiency of the nanocomposite was also calculated and estimated to be 1.52 and 1.26 times improved over LaCoO3 and P-g-C3N4, respectively. Overall, this work gives insight into less costly and simple Z-scheme heterojunctions for solar to hydrogen conversion with high efficiency
Current trends in strategies to improve photocatalytic performance of perovskites materials for solar to hydrogen production
No full textPhotocatalytic hydrogen production via water splitting is one of the favorable technologies for the solar energy conversion to renewable and sustainable energy; however, semiconductor materials under consideration have lower efficiency, selectivity and stability. Recently, perovskites are most demanding semiconductor photocatalysts belonging to very important family of materials and exhibit exceptional visible light response towards photocatalytic application. This review highlights recent developments in perovskite materials and their modification approaches for improved photocatalytic H2 production. Primarily, the classification of perovskites based on structural developments; in particular, thermodynamics engineering to minimize energy barriers are discussed. Different approaches for fabrication of perovskite materials by metal and non-metal doping, while focusing on mechanism of Schottky barrier and Surface Plasmon phenomenon to improve photocatalytic efficiency are explored. This review also presents band engineering approaches in perovskites such as site substitution, solid-solution formation and nitrification of perovskites to maximize H2 evolution. Elaboration of layered perovskite and improvement in their efficiency by various fabrication techniques including Z-scheme formation and composite of perovskite with TiO2 and carbon-based composites including g-C3N4 and rGO in terms of multi-component heterojunction based on transfer of electron-hole pairs are critically deliberated. Finally, future perspectives of perovskite materials and their efficiency enhancement approaches for sustainable solar to hydrogen production has been suggested
Usability of Data Warehousing and Data Mining for Interactive Decision Making in Textile Sector
No full textData warehouse is one of the most rapidly growing areas in management information system. With this approach, data for Executive Information System (EIS) and Decision Support System (DSS) applications are separated from operational data and stored in a separate database. This process is called data warehousing. The major advantages of this approach are: improved in performance, better data quality, and the ability to consolidate and summarize data from heterogeneous systems. A data warehouse is part of a larger infrastructure that includes legacy data sources, external data sources, a repository, data acquisition software, and user interface and related analytical tools. The aim of this research work is to elaborate that how the textile industry can manage and improve their production capacity and resources at optimum level to produce a good quality result using data warehousing and data mining techniques. This research work is conduction in Masood Textile Mills Limited, Faisalabad, Pakistan (MTML). The results may hopefully opened-up an era of research and methodology that could further benefit the Industry to support in decision support system
APGAR Score of Neonates Born to Anemic Mothers versus Non-Anemic Mothers
No full textObjective: To determine the effect of maternal iron deficiency anemia on APGAR score of neonates at one minute.Patients and Methods: This cross-sectional study was conducted at Aziz Bhatti Shaheed Teaching Hospital Gujrat from January 2017 to November 2017. In total 380 patients (50% anemic and 50% non-anemic mothers) were included in study. Grouping into anemic and non-anemic groups was done, based on their hemoglobin level, MCV, MCH and ferritin levels. APGAR score at 1 minute was noted in neonates born to both groups. Data was analyzed using SPSS 20.0. Chi square test was applied to evaluate the difference of APGAR score.Results: Mean age in anemic was 27+4.6 years and in non-anemic 26+5.1 years. The mean hemoglobin among anemic was 8.9+2.1 g/dl and among non-anemic 12.3+1.2 g/dL. Mean MCV in non-anemic 85.7+3.8 fl, while among anemic was 62.4+4.1 fl Mean ferritin levels among anemic were 7.4+1.1 ng/ml. Neonates delivered by anemic mothers had mean APGAR score of 6.5+0.2 and those delivered to non-anemic had 8.7+0.5. The APGAR score of neonates delivered by anemic and non-anemic showed a significant difference (p-value 0.00). The relative risk of having low APGAR score of infant in anemic compared to non-anemic mothers was 29.00 (95% CI, 13.1798-63.8098) with p<0.0001.Conclusion: Maternal anemia is significantly associated with poor APGAR score in neonates
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