Displaying publications 41 - 60 of 2877 in total

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  1. Comparative advantages analysis of oxidative torrefaction for solid biofuel production and property upgrading
    Zhang C, Chen WH, Ho SH, Zhang Y, Lim S
    Bioresour Technol, 2023 Oct;386:129531.
    PMID: 37473787 DOI: 10.1016/j.biortech.2023.129531
    This study performs the comparative advantage analysis of oxidative torrefaction of corn stalks to investigate the advantages of oxidative torrefaction for biochar fuel property upgrading. The obtained results indicate that oxidative torrefaction is more efficient in realizing mass loss and energy density improvement, as well as elemental carbon accumulation and surface functional groups removal, and thus leads to a better fuel property. The maximum values of relative mass loss, higher heating value, enhancement factor, and energy yield are 3.00, 1.10, 1.03, and 0.87, respectively. The relative elemental carbon, hydrogen, and oxygen content ranges are 1.30-3.10, 1.50-3.30, and 2.00-6.80, respectively. In addition, an excellent linear distribution is obtained between the comprehensive pyrolysis index and torrefaction severity index, with elemental carbon and oxygen component variation stemming from pyrolysis performance correlating to the elemental component and valance.
    Matched MeSH terms: Temperature
  2. Fulltext Native diversity buffers against severity of non-native tree invasions
    Delavaux CS, Crowther TW, Zohner CM, Robmann NM, Lauber T, van den Hoogen J, et al.
    Nature, 2023 Sep;621(7980):773-781.
    PMID: 37612513 DOI: 10.1038/s41586-023-06440-7
    Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species1,2. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies3,4. Here, leveraging global tree databases5-7, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions.
    Matched MeSH terms: Temperature
  3. Robust cross-linked cyclodextrin glucanotransferase from Bacillus lehensis G1 aggregates using an improved cross-linker and a new co-aggregant for the production of cyclodextrins
    Jailani N, Jaafar NR, Rahman RA, Illias RM
    Enzyme Microb Technol, 2023 Sep;169:110283.
    PMID: 37433237 DOI: 10.1016/j.enzmictec.2023.110283
    One of the potentials of carrier-free cross-linked enzyme aggregates (CLEA) immobilization is the ability to be separated and reuse. Yet, it might be impeded by the poor mechanical stability resulting low recyclability. CLEA of CGTase from Bacillus lehensis G1 (CGTase G1-CLEA) using chitosan (CS) as a cross-linker demonstrated high activity recovery however, displayed poor reusability. Therefore, the relationship between mechanical strength and reusability is studied by enhancing the CS mechanical properties and applying a new co-aggregation approach. Herein, CS was chemically cross-linked with glutaraldehyde (GA) and GA was introduced as a co-aggregant (coGA). CGTase G1-CLEA developed using an improved synthesized chitosan-glutaraldehyde (CSGA) cross-linker and a new coGA technique showed to increase its mechanical stability which retained 63.4% and 52.2%, respectively compared to using CS that remained 33.1% of their initial activity after stirred at 500 rpm. The addition of GA impacted the morphology and interaction consequently stabilizing the CLEAs durability in production of cyclodextrins. As a result, the reusability of CGTase G1-CLEA with CSGA and coGA increased by 56.6% and 42.8%, respectively compared to previous CLEA after 5 cycles for 2 h of reaction. This verifies that the mechanical strength of immobilized enzyme influences the improvement of its operational stability.
    Matched MeSH terms: Temperature
  4. Thermal design and zeotropic working fluids mixture selection optimization for a solar waste heat driven combined cooling and power system
    Kheimi M, K Salamah S, A Maddah H, Mustafa Al Bakri Abdullah M
    Chemosphere, 2023 Sep;335:139036.
    PMID: 37245592 DOI: 10.1016/j.chemosphere.2023.139036
    Considering the limitation of fossil fuel resources and their environmental effects, the use of renewable energies is increasing. In the current research, a combined cooling and power production (CCPP) system is investigated, the energy source of which is solar energy. Solar energy absorbs by solar flat plate collectors (SFPC). The system produces power with the help of an organic Rankine cycle (ORC). An ejector refrigeration cycle (ERC) system is considered to provide cooling capacity. The motive flow is supplied from the expander extraction in the ERC system. Various working fluids have been applied so far for the ORC-ERC cogeneration system. This research investigates the effect of using two working fluids R-11 and R-2545fa, and the zeotropic mixtures obtained by mixing these two fluids. A multiobjective optimization process is considered to select the appropriate working fluid. In the optimization design process, the goal is to minimize the total cost rate (TCR) and maximize the exergy efficiency of the system. The design variables are the quantity of SFPC, heat recovery vapor generator (HRVG) pressure, ejector motive flow pressure, evaporator pressure, condenser pressure, and entertainment ratio. Finally, it is observed that using zeotropic mixtures obtained from these two refrigerants has a better result than using pure refrigerants. Finally, it is observed that the best performance is achieved when R-11 and R245fa are mixed with a ratio of 80 to 20%, respectively and led to 8.5% improvement in exergy efficiency, while the increase in TCR is only 1.5%.
    Matched MeSH terms: Cold Temperature; Hot Temperature*
  5. Performance assessment and multiobjective optimization of a biomass waste-fired gasification combined cycle for emission reduction
    Hai T, Alshahri AH, Mohammed AS, Sharma A, Almujibah HR, Mohammed Metwally AS, et al.
    Chemosphere, 2023 Sep;334:138980.
    PMID: 37207897 DOI: 10.1016/j.chemosphere.2023.138980
    The use of renewable fuels leads to reduction in the use of fossil fuels and environmental pollutants. In this study, the design and analysis of a CCPP based on the use of syngas produced from biomass is discussed. The studied system includes a gasifier system to produce syngas, an external combustion gas turbine and a steam cycle to recover waste heat from combustion gases. Design variables include syngas temperature, syngas moisture content, CPR, TIT, HRSG operating pressure, and PPTD. The effect of design variables on performance components such as power generation, exergy efficiency and total cost rate of the system is investigated. Also, through multi-objective optimization, the optimal design of the system is done. Finally, it is observed that at the final decisioned optimal point, the produced power is 13.4 MW, the exergy efficiency is 17.2%, and the TCR is 118.8 $/h.
    Matched MeSH terms: Hot Temperature; Temperature
  6. Anthropogenic climate change exacerbates the risk of successive flood-heat extremes: Multi-model global projections based on the Inter-Sectoral Impact Model Intercomparison Project
    Zhou J, Wu C, Yeh PJ, Ju J, Zhong L, Wang S, et al.
    Sci Total Environ, 2023 Sep 01;889:164274.
    PMID: 37209749 DOI: 10.1016/j.scitotenv.2023.164274
    The successive flood-heat extreme (SFHE) event, which threatens the securities of human health, economy, and building environment, has attracted extensive research attention recently. However, the potential changes in SFHE characteristics and the global population exposure to SFHE under anthropogenic warming remain unclear. Here, we present a global-scale evaluation of the projected changes and uncertainties in SFHE characteristics (frequency, intensity, duration, land exposure) and population exposure under the Representative Concentration Pathway (RCP) 2.6 and 6.0 scenarios, based on the multi-model ensembles (five global water models forced by four global climate models) within the Inter-Sectoral Impact Model Intercomparison Project 2b framework. The results reveal that, relative to the 1970-1999 baseline period, the SFHE frequency is projected to increase nearly globally by the end of this century, especially in the Qinghai-Tibet Plateau (>20 events/30-year) and the tropical regions (e.g., northern South America, central Africa, and southeastern Asia, >15 events/30-year). The projected higher SFHE frequency is generally accompanied by a larger model uncertainty. By the end of this century, the SFHE land exposure is expected to increase by 12 % (20 %) under RCP2.6 (RCP6.0), and the intervals between flood and heatwave in SFHE tend to decrease by up to 3 days under both RCPs, implying the more intermittent SFHE occurrence under future warming. The SFHE events will lead to the higher population exposure in the Indian Peninsula and central Africa (<10 million person-days) and eastern Asia (<5 million person-days) due to the higher population density and the longer SFHE duration. Partial correlation analysis indicates that the contribution of flood to the SFHE frequency is greater than that of heatwave for most global regions, but the SFHE frequency is dominated by the heatwave in northern North America and northern Asia.
    Matched MeSH terms: Hot Temperature*
  7. Comparison of two newly suggested power, refrigeration, and hydrogen production, for moving towards sustainability schemes using improved solar-powered evolutionary algorithm optimization
    Hai T, Abd El-Salam NM, Kh TI, Chaturvedi R, El-Shafai W, Farhang B
    Chemosphere, 2023 Sep;336:139160.
    PMID: 37327820 DOI: 10.1016/j.chemosphere.2023.139160
    In the third millennium, developing countries will confront significant environmental problems such as ozone depletion, global warming, the shortage of fossil resources, and greenhouse gas emissions. This research looked at a multigenerational system that can generate clean hydrogen, fresh water, electricity, heat, and cooling. The system's components include Rankine and Brayton cycles, an Organic Rankine Cycle (ORC), flash desalination, an Alkaline electrolyzer, and a solar heliostat. The proposed process has been compared for two different start-up modes with a combustion chamber and solar heliostat to compare renewable and fossil fuel sources. This research evaluated various characteristics, including turbine pressure, system efficiency, solar radiation, and isentropic efficiency. The energy and exergy efficiency of the proposed system were obtained at around 78.93% and 47.56%, respectively. Exergy study revealed that heat exchangers and alkaline electrolyzers had the greatest exergy destruction rates, at 78.93% and 47.56%, respectively. The suggested system produces 0.04663 kg/s of hydrogen. Results indicate that at the best operational conditions, the exergetic efficiency, power, and hydrogen generation of 56%, 6000 kW, and 1.28 kg/s is reached, respectively. Also, With a 15% improvement in the Brayton cycle's isentropic efficacy, the quantity of hydrogen produced increases from 0.040 kg/s to 0.0520 kg/s.
    Matched MeSH terms: Cold Temperature
  8. Diagnostic models to predict nuclear DNA and mitochondrial DNA recovery from incinerated teeth
    Rahmat RA, Humphries MA, Saedon NA, Self PG, Linacre AMT
    Int J Legal Med, 2023 Sep;137(5):1353-1360.
    PMID: 37306739 DOI: 10.1007/s00414-023-03017-x
    Teeth are frequently used for human identification from burnt remains, as the structure of a tooth is resilient against heat exposure. The intricate composition of hydroxyapatite (HA) mineral and collagen in teeth favours DNA preservation compared to soft tissues. Regardless of the durability, the integrity of the DNA structure in teeth can still be disrupted when exposed to heat. Poor DNA quality can negatively affect the success of DNA analysis towards human identification. The process of isolating DNA from biological samples is arduous and costly. Thus, an informative pre-screening method that could aid in selecting samples that can potentially yield amplifiable DNA would be of excellent value. A multiple linear regression model to predict the DNA content in incinerated pig teeth was developed based on the colourimetry, HA crystallite size and quantified nuclear and mitochondrial DNA. The chromaticity a* was found to be a significant predictor of the regression model. This study outlines a method to predict the viability of extracting nuclear and mitochondrial DNA from pig teeth that were exposed to a wide range of temperatures (27 to 1000 °C) with high accuracy (99.5-99.7%).
    Matched MeSH terms: Hot Temperature
  9. Eco-friendly drying techniques: a comparison of solar, biomass, and hybrid dryers
    Prabhu N, Saravanan D, Kumarasamy S
    Environ Sci Pollut Res Int, 2023 Sep;30(42):95086-95105.
    PMID: 37582893 DOI: 10.1007/s11356-023-28807-z
    Solar energy provides desired thermal energy for diverse applications, including industrial heating, domestic cooking, power generation, desalination, and agri-food preservation. Despite extensive research on solar drying from the scientific community, there are limited practical applications for small-scale use. This review attempts to analyze the design features of three specific types of dryers for food drying applications: solar evacuated tube dryers, biomass dryers, and hybrid solar dryers. The thermal performance of the three dryers is evaluated in terms of drying time, moisture removal, and temperature attained during drying. The review also assesses the prospects of solar dryers, highlighting the need for further research into innovative designs and advanced drying capabilities. The study provides valuable information for enhancing dryer performance with various integrated solutions.
    Matched MeSH terms: Temperature
  10. Novel PEX1 mutations in fibroblasts from children with Zellweger spectrum disorders exhibit temperature sensitive characteristics
    Liang JS, Hung KL, Lin LJ, Ong WP, Keng WT, Lu JF
    Epilepsy Behav, 2023 Aug;145:109266.
    PMID: 37385119 DOI: 10.1016/j.yebeh.2023.109266
    Zellweger spectrum disorders (ZSD) are rare autosomal recessive disorders caused by defects in peroxisome biogenesis factor (PEX; peroxin) genes leading to impaired transport of peroxisomal proteins with peroxisomal targeting signals (PTS). Four patients, including a pair of homozygotic twins, diagnosed as ZSD by genetic study with different clinical presentations and outcomes as well as various novel mutations are described here. A total of 3 novel mutations, including a nonsense, a frameshift, and a splicing mutation, in PEX1 from ZSD patients were identified and unequivocally confirmed that the p.Ile989Thr mutant PEX1 exhibited temperature-sensitive characteristics and is associated with milder ZSD. The nature of the p.Ile989Thr mutant exhibited different characteristics from that of the other previously identified temperature-sensitive p.Gly843Asp PEX1 mutant. Transcriptome profiles under nonpermissive vs. permissive conditions were explored to facilitate the understanding of p.Ile989Thr mutant PEX1. Further investigation of molecular mechanisms may help to clarify potential genetic causes that could modify the clinical presentation of ZSD.
    Matched MeSH terms: Temperature
  11. Recovery and utilisation of waste heat from flue/exhaust gases: a bibliometric analysis (2010-2022)
    Nyakuma BB, Mahyon NI, Chiong MS, Rajoo S, Pesiridis A, Wong SL, et al.
    Environ Sci Pollut Res Int, 2023 Aug;30(39):90522-90546.
    PMID: 37479929 DOI: 10.1007/s11356-023-28791-4
    The recovery and utilisation of waste heat from flue/exhaust gases (RU/WHFG) could potentially provide sustainable energy while curbing pollutant emissions. Over time, the RU/WHFG research landscape has gained significant traction and yielded innovative technologies, sustainable strategies, and publications. However, critical studies highlighting current advancements, publication trends, research hotspots, major stakeholders, and future research directions on RU/WHFG research remain lacking. Therefore, this paper presents a comprehensive bibliometric analysis and literature review of the RU/WHFG research landscape based on publications indexed in Scopus. Results showed that 123 publications and 2191 citations were recovered between 2010 and 2022. Publication trends revealed that the growing interest in RU/WHFG is mainly due to environmental concerns (e.g. pollution, global warming, and climate change), research collaborations, and funding availability. Stakeholder analysis revealed that numerous researchers, affiliations, and countries have actively contributed to the growth and development of RU/WHFG. Lin Fu and Tsinghua University (China) are the most prolific researchers and affiliations, whereas the National Natural Science Foundation of China (NSFC) and China are the most prolific funder and country, respectively. Funding availability from influential schemes such as NSFC has accounted for China's dominance. Keyword co-occurrence identified three major research hotspots, namely, thermal energy utilisation and management (cluster 1), integrated energy and resource recovery (cluster 2), and system analysis and optimisation (cluster 3). Literature review revealed that researchers are currently focused on maximising thermodynamic/energy efficiency, fuel minimisation, and emission reduction. Despite progress, research gaps remain in low-temperature/low-grade waste heat recovery, utilisation, storage, life cycle, and environmental impact analysis.
    Matched MeSH terms: Hot Temperature*; Temperature
  12. Design configuration and operational parameters of bi-fluid PVT collectors: an updated review
    Al-Waeli AHA, Sopian K, Kazem HA, Chaichan MT
    Environ Sci Pollut Res Int, 2023 Jul;30(34):81474-81492.
    PMID: 36689112 DOI: 10.1007/s11356-023-25321-0
    The bi-fluid photovoltaic thermal (PVT) collector was introduced to provide more heating options along with improved cooling capabilities for the PV module. Since its introduction, this type of PVT system has been investigated thoroughly in various original works. In this review paper, we intend to put the concept and applications of this technology into question and revise the main achievements and discoveries through research and development with a focus on climatic and operational parameters. The paper encompasses a critical review of the discussed research and future directions for PVT collectors. The main utilized operational modes are discussed in detail, which are (i) water used in both channels, (ii) water in one channel and air in the other, and (iii) air in both channels. The modes were found to lead to different enhancement and performance effects for the utilized photovoltaic modules. The impact of mass flow rate was also taken by keeping one working fluid constant while varying the other to obtain its impact on the energy and exergy efficiency of the collector. In some cases, the fluids were run simultaneously and, in other cases, independently.
    Matched MeSH terms: Cold Temperature*
  13. Combined cross-linked enzyme aggregates of cyclodextrin glucanotransferase and maltogenic amylase from Bacillus lehensis G1 for maltooligosaccharides synthesis
    Yip YS, Manas NHA, Jaafar NR, Rahman RA, Puspaningsih NNT, Illias RM
    Int J Biol Macromol, 2023 Jul 01;242(Pt 1):124675.
    PMID: 37127056 DOI: 10.1016/j.ijbiomac.2023.124675
    Maltooligosaccharides (MOS) are functional oligosaccharides that can be synthesized through enzymatic cascade reaction between cyclodextrin glucanotransferase (CGTase) and maltogenic amylase (Mag1) from Bacillus lehensis G1. To address the problems of low operational stability and non-reusability of free enzymes, both enzymes were co-immobilized as combined cross-linked enzyme aggregates (Combi-CLEAs-CM) with incorporation of bovine serum albumin (BSA) and Tween 80 (Combi-CLEAs-CM-add). Combi-CLEAs-CM and Combi-CLEAs-CM-add showed activity recoveries of 54.12 % and 69.44 %, respectively after optimization. Combi-CLEAs-CM-add showed higher thermal stability at higher temperatures (40 °C) with longer half-life (46.20 min) as compared to those of free enzymes (36.67 min) and Combi-CLEAs-CM (41.51 min). Both combi-CLEAs also exhibited higher pH stability over pH 5 to pH 9, and displayed excellent reusability with >50 % of initial activity retained after four cycles. The reduction in Km value of about 22.80 % and 1.76-fold increase in starch hydrolysis in comparison to Combi-CLEAs-CM attested the improvement of enzyme-substrate interaction by Tween 80 and pores formation by BSA in Combi-CLEAs-CM-add. The improved product specificity of Combi-CLEAs-CM-add also produced the highest yield of MOS (492 mg/g) after 3 h. Therefore, Combi-CLEAs-CM-add with ease of preparation, excellent reusability and high operational stability is believed to be highly efficacious biocatalyst for MOS production.
    Matched MeSH terms: Temperature
  14. Thermal and mechanical characterization of composite materials from industrial plastic wastes and recycled nylon fibers for floor paving tiles application
    Owen MM, Achukwu EO, Romli AZ, Abdullah AHB, Ramlee MH, Shuib SB
    Waste Manag, 2023 Jul 01;166:25-34.
    PMID: 37141784 DOI: 10.1016/j.wasman.2023.04.038
    Industrial plastic waste is growing globally at an alarming rate and environmental pollution from traditional landfill disposal and incineration treatments are of great concern. As a strategy to reduce plastic pollution, value-added composite materials from industrial plastic wastes reinforced with recycled nylon fibers for use in floor paving tile applications were developed. This is to address the disadvantages of existing ceramic tiles which are relatively heavy, brittle, and expensive. The plastic waste composite structures were produced via compression molding technique at an optimized randomly oriented constant fiber volume fraction of 50 wt% after the initial sorting, cleaning, drying, pulverizing, and melt-mixing. The molding temperature, pressure, and time for the composite's structures were 220 ℃, 65 kg.cm-3, and 5 min respectively. The composites' thermal, mechanical, and microstructural properties were characterized in accordance with appropriate ASTM standards. From the results obtained, the differential scanning calorimetry (DSC) of mixed plastic wastes and nylon fiber wastes showed a processing temperature range of 130-180 ℃, and 250 ℃ respectively. Thermal degradation temperature (TGA) of the plastic and nylon fiber waste composites were stable above 400 ℃ with maximum bending strength, however, the reinforced plastic waste sandwiched composite structures had outstanding mechanical properties indicating unique characteristics suitable for floor paving tiles. Hence, the current research has developed tough and lightweight tiles composites that are economically viable, and their application will contribute to the development of the building and construction sectors thereby reducing about 10-15% of annual plastic waste generation and a sustainable environment.
    Matched MeSH terms: Temperature
  15. The effect of calcium hydroxide addition on enhancing ammonia recovery during thermophilic composting in a self-heated pilot-scale reactor
    Tie HO, Che Man H, Koyama M, Syukri F, Md Yusoff F, Toda T, et al.
    Waste Manag, 2023 Jul 01;166:194-202.
    PMID: 37178588 DOI: 10.1016/j.wasman.2023.04.046
    A modified outdoor large-scale nutrient recycling system was developed to compost organic sludge and aimed to recover clean nitrogen for the cultivation of high-value-added microalgae. This study investigated the effect of calcium hydroxide addition on enhancing NH3 recovery in a pilot-scale reactor self-heated by metabolic heat of microorganisms during thermophilic composting of dewatered cow dung. 350 kg-ww of compost was prepared at the ratio of 5: 14: 1 (dewatered cowdung: rice husk: compost-seed) in a 4 m3 cylindrical rotary drum composting reactor for 14 days of aerated composting. High compost temperature up to 67 °C was observed from day 1 of composting, proving that thermophilic composting was achieved through the self-heating process. The temperature of compost increases as microbial activity increases and temperature decreases as organic matter decreases. The high CO2 evolution rate on day 0-2 (0.02-0.08 mol/min) indicated that microorganisms are most active in degrading organic matter. The increasing conversion of carbon demonstrated that organic carbon was degraded by microbial activity and emitted as CO2. The nitrogen mass balance revealed that adding calcium hydroxide to the compost and increasing the aeration rate on day 3 volatilized 9.83 % of the remaining ammonium ions in the compost, thereby improving the ammonia recovery. Moreover, Geobacillus was found to be the most dominant bacteria under elevated temperature that functions in the hydrolysis of non-dissolved nitrogen for better NH3 recovery. The presented results show that by thermophilic composting 1 ton-ds of dewatered cowdung for NH3 recovery, up to 11.54 kg-ds of microalgae can be produced.
    Matched MeSH terms: Hot Temperature*
  16. Is microbial adhesion affected by the build orientation of a 3-dimensionally printed denture base resin?
    Yacob N, Ahmad NA, Safii SH, Yunus N, Abdul Razak F
    J Prosthet Dent, 2023 Jul;130(1):131.e1-131.e7.
    PMID: 37210224 DOI: 10.1016/j.prosdent.2023.04.017
    STATEMENT OF PROBLEM: How the build orientation of a 3-dimensionally (3D) printed denture affects microbial adhesion is unclear.

    PURPOSE: The purpose of this in vitro study was to compare the adherence of Streptococcus spp. and Candida spp. on 3D-printed denture bases prepared at different build orientations with conventional heat-polymerized resin.

    MATERIAL AND METHODS: Resin specimens (n=5) with standardized 28.3 mm2 surface area were 3D printed at 0 and 60 degrees, and heat-polymerized (3DP-0, 3DP-60, and HP, respectively). The specimens were placed in a Nordini artificial mouth (NAM) model and exposed to 2 mL of clarified whole saliva to create a pellicle-coated substratum. Suspensions of Streptococcus mitis and Streptococcus sanguinis, Candida albicans and Candida glabrata, and a mixed species, each at 108 cfu/mL were pumped separately into the model for 24 hours to promote microbial adhesion. The resin specimens were then removed, placed in fresh media, and sonicated to dislodge attached microbes. Each suspension (100 μL) was aliquoted and spread on agar plates for colony counting. The resin specimens were also examined under a scanning electron microscope. The interaction between types of specimen and groups of microbes was examined with 2-way ANOVA and then further analysis with Tukey honest significant test and Kruskal-Wallis post hoc tests (α=.05).

    RESULTS: A significant interaction was observed between the 3DP-0, 3DP-60, and HP specimen types and the groups of microbes adhering to the corresponding denture resin specimens (P

    Matched MeSH terms: Hot Temperature
  17. Fulltext Ultra-effective modified clinoptilolite adsorbent for selective thorium removal from radioactive residue
    Alotaibi AM, Ismail AF, Aziman ES
    Sci Rep, 2023 Jun 08;13(1):9316.
    PMID: 37291241 DOI: 10.1038/s41598-023-36487-5
    This study investigated the efficacy of using phosphate-modified zeolite (PZ) as an adsorbent for removing thorium from aqueous solutions. The effects of various factors such as contact time, adsorbent mass, initial thorium concentration, and pH value of the solution on the removal efficiency were analyzed using the batch technique to obtain optimum adsorption condition. The results revealed that the optimal conditions for thorium adsorption were a contact time of 24 h, 0.03 g of PZ adsorbent, pH 3, and a temperature of 25 °C. Isotherm and kinetics parameters of the thorium adsorption on PZ were also determined, with equilibrium studies showing that the experimental data followed the Langmuir isotherm model. The maximum adsorption capacity (Qo) for thorium was found to be 17.3 mg/g with the Langmuir isotherm coefficient of 0.09 L/mg. Using phosphate anions to modify natural zeolite increased its adsorption capacity. Furthermore, adsorption kinetics studies demonstrated that the adsorption of thorium onto PZ adsorbent fitted well with the pseudo-second-order model. The applicability of the PZ adsorbent in removing thorium from real radioactive waste was also investigated, and nearly complete thorium removal was achieved (> 99%) from the leached solution obtained from cracking and leaching processes of rare earth industrial residue under optimized conditions. This study elucidates the potential of PZ adsorbent for efficient removal of thorium from rare earth residue via adsorption, leading to a reduction in waste volume for ultimate disposition.
    Matched MeSH terms: Temperature
  18. Influence of Co3O4-based catalysts on N2O catalytic decomposition and NO conversion
    Inayat A, Rocha-Meneses L, Ayoub M, Ullah S, Abdullah AZ, Naqvi SR, et al.
    Environ Sci Pollut Res Int, 2023 Jun;30(28):72224-72235.
    PMID: 37170050 DOI: 10.1007/s11356-023-27371-w
    This study investigated the effect of different Co3O4-based catalysts on the catalytic decomposition of nitrous oxide (N2O) and on nitric oxide (NO) conversion. The experiments were carried out using various reaction temperatures, alkaline solutions, pH, mixing conditions, aging times, space velocities, impregnation loads, and compounds. The results showed that Co3O4 catalysts prepared by precipitation methods have the highest catalytic activity and N2O conversion, even at low reaction temperatures, while the commercial nano and powder forms of Co3O4 (CS) have the lowest performance. The catalysts become inactive at temperatures below 400 °C, and their activity is strongly influenced by the mixing temperature. Samples without stirring during the aging process have higher catalytic activity than those with stirring, even at low reaction temperatures (200-300 °C). The catalytic activity of Co3O4 PM1 decreases with low W/F values and low reaction temperatures. Additionally, the catalyst's performance tends to increase with the reduction process. The study suggests that cobalt-oxide-based catalysts are effective in N2O catalytic decomposition and NO conversion. The findings may be useful in the design and optimization of catalytic systems for N2O and NO control. The results obtained provide important insights into the development of highly efficient, low-cost, and sustainable catalysts for environmental protection.
    Matched MeSH terms: Temperature
  19. Fulltext Waste heat recovery research - a systematic bibliometric analysis (1991 to 2020)
    Kuah CT, Koh QY, Rajoo S, Wong KY
    Environ Sci Pollut Res Int, 2023 Jun;30(28):72074-72100.
    PMID: 35716302 DOI: 10.1007/s11356-022-21377-6
    Human usage of non-renewable energy resources has caused many environmental issues, which include air pollution, global warming, and climate irregularities. To counter these issues, researchers have been seeking after alternative renewable energy sources and ways to manage energy more efficiently. This is where energy recovery technologies such as waste heat recovery (WHR) come into play. WHR is a form of waste to energy conversion. Waste heat can be captured and converted into usable energy instead of dumping it into the environment. In the more recent years, the WHR research field has gained great attention in the scientific community as well as in some energy-intensive industries. This article presents a bibliometric overview of the academic research on WHR over the span of 30 years from 1991 to 2020. A total of 5682 documents from Web of Science (WoS) have been retrieved and analyzed using various bibliometric methods, including performance analysis and network analysis. The analyses were performed on different actors in the field, i.e., funding agencies, journals, authors, organizations, and countries. In addition, several network mappings were done based on co-citation, co-authorship, and co-occurrences of keywords analyses. The research identified the most productive and influential actors in the field, established and emergent research topics, as well as the interrelations and collaboration patterns between different actors. The findings can be a robust roadmap for further research in this field.
    Matched MeSH terms: Hot Temperature*
  20. Lactic acid fermentation of food waste as storage method prior to biohydrogen production: Effect of storage temperature on biohydrogen potential and microbial communities
    Roslan E, Magdalena JA, Mohamed H, Akhiar A, Shamsuddin AH, Carrere H, et al.
    Bioresour Technol, 2023 Jun;378:128985.
    PMID: 37001698 DOI: 10.1016/j.biortech.2023.128985
    This study aims to investigate the impact of utilizing lactic acid fermentation (LAF) as storage method of food waste (FW) prior to dark fermentation (DF). LAF of FW was carried out in batches at six temperatures (4 °C, 10 °C, 23 °C, 35 °C, 45 °C, and 55 °C) for 15 days followed by biological hydrogen potential (BHP) tests. Different storage temperatures resulted in different metabolites distribution, with either lactate or ethanol being dominant (159.2 ± 20.6 mM and 234.4 ± 38.2 mM respectively), but no negative impact on BHP (averaging at 94.6 ± 25.1 mL/gVS). Maximum hydrogen production rate for stored FW improved by at least 57%. Microbial analysis showed dominance of lactic acid bacteria (LAB) namely Lactobacillus sp., Lactococcus sp., Weisella sp., Streptococcus sp. and Bacillus sp. after LAF. Clostridium sp. emerged after DF, co-existing with LAB. Coupling LAF as a storage method was demonstrated as a novel strategy of FW management for DF, for a wide range of temperatures.
    Matched MeSH terms: Temperature
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