•Six diverse biomass fuels are evaluated as an alternative renewable energy source for the UK.•Thermal degradation of biomasses by using variable inert to oxidising environments.•Pyrolytic, ...combustion and kinetic analyses with the help of TGA, DTG and DSC.•High rates of thermal decomposition are noted in oxidising atmosphere.•The reaction order 0.5 modelled fitted well for all biomass fuels.
This study investigates the thermal and kinetic analysis of six diverse biomass fuels, in order to provide valuable information for power and energy generation. Pyrolytic, combustion and kinetic analyses of barley straw, miscanthus, waste wood, wheat straw, short rotation coppicing (SRC) willow and wood pellet were examined by non-isothermal thermogravimetry analyser (TGA), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) techniques. Biomass fuels were thermally degraded under N2, air, CO2 and the selected oxy-fuel (30% O2/70% CO2) reaction environments. The thermal degradation under inert N2 and CO2 atmospheres showed an almost identical rate of weight loss (R), reactivity (RM × 103) and activation energy (Ea) profiles. Similar profiles for R, RM and Ea were observed for the environments under air (21% O2/79% N2) and the oxy-fuel combustion. Results indicated that the thermal decomposition rate for biomass fuels in an oxidising condition was faster than in an inert atmosphere, favourable effect on thermal degradation of biomass fuels was observed when oxygen content increased from 21 to 30%. Higher activation energies with lower reactivity were observed for the biomass fuels that have low cellulosic contents as compared to the other fuels. Regression analysis confirmed that the reaction order 0.5 modelled fitted well for all biomass samples. All these findings will provide valuable information and promote the advancement of future researches in this field.
Over the years, scarcity of fresh potable water has increased the demand for clean water. Meanwhile, with the advent of nanotechnology, the use of nanomaterials for photocatalytic degradation of ...pollutants in wastewaters has increased. Herein, a new type of nanohybrids of La- and Mn-codoped bismuth ferrite (BFO) nanoparticles embedded into transition-metal carbide sheets (MXene–Ti3C2) were prepared by a low-cost double-solvent sol–gel method and investigated for their catalytic activity in dark and photoinduced conditions. The photoluminescence results showed that pure BFO has the highest electron hole recombination rate as compared to all the codoped BFO/Ti3C2 nanohybrids. The higher electron–hole pair generation rate of the nanohybrids provides a suitable environment for fast degradation of organic dye molecules. The band gap of the prepared nanohybrid was tuned to 1.73 eV. Moreover, the BLFO/Ti3C2 and BLFMO-5/Ti3C2 degraded 92 and 93% of the organic pollutant, respectively, from water in dark and remaining in the light spectrum. Therefore, these synthesized nanohybrids could be a promising candidate for catalytic and photocatalytic applications in future.
Intellectual disability (ID) is a clinically and genetically heterogeneous disorder, affecting 1-3% of the general population. Although research into the genetic causes of ID has recently gained ...momentum, identification of pathogenic mutations that cause autosomal recessive ID (ARID) has lagged behind, predominantly due to non-availability of sizeable families. Here we present the results of exome sequencing in 121 large consanguineous Pakistani ID families. In 60 families, we identified homozygous or compound heterozygous DNA variants in a single gene, 30 affecting reported ID genes and 30 affecting novel candidate ID genes. Potential pathogenicity of these alleles was supported by co-segregation with the phenotype, low frequency in control populations and the application of stringent bioinformatics analyses. In another eight families segregation of multiple pathogenic variants was observed, affecting 19 genes that were either known or are novel candidates for ID. Transcriptome profiles of normal human brain tissues showed that the novel candidate ID genes formed a network significantly enriched for transcriptional co-expression (P<0.0001) in the frontal cortex during fetal development and in the temporal-parietal and sub-cortex during infancy through adulthood. In addition, proteins encoded by 12 novel ID genes directly interact with previously reported ID proteins in six known pathways essential for cognitive function (P<0.0001). These results suggest that disruptions of temporal parietal and sub-cortical neurogenesis during infancy are critical to the pathophysiology of ID. These findings further expand the existing repertoire of genes involved in ARID, and provide new insights into the molecular mechanisms and the transcriptome map of ID.
The current environmental and potable water crisis requires technological advancement to tackle the issues caused by different organic pollutants. Herein, we report the degradation of organic ...pollutants such as Congo Red and acetophenone from aqueous media using visible light irradiation. To harvest the solar energy for photocatalysis, we fabricated a nanohybrid system composed of bismuth ferrite nanoparticles with two-dimensional (2D) MXene sheets, namely, the BiFeO3 (BFO)/Ti3C2 (MXene) nanohybrid, for enhanced photocatalytic activity. The hybrid BFO/MXene is fabricated using a simple and low-cost double-solvent solvothermal method. The SEM and TEM images showed that the BFO nanoparticles are attached onto the surface of 2D MXene sheets. The photocatalytic degradation achieved by the hybrid is found to be 100% in 42 min for the organic dye (Congo Red) and 100% for the colorless aqueous pollutant (acetophenone) in 150 min. The BFO/MXene hybrid system exhibited a large surface area of 147 m2 g–1 measured via the Brunauer–Emmett–Teller sorption–desorption technique, which is found to be the largest among all BFO nanoparticles and derivatives. The photoluminescence spectra indicate a low electron–hole recombination rate. Fast and efficient degradation of organic molecules is caused by two factors: larger surface area and lower electron–hole recombination rate, which makes the BFO/MXene nanohybrid a highly efficient photocatalyst and a promising candidate for many future applications.
In this article, the flow and heat transfer of Eyring Powell fluid over a continuously moving surface in the presence of a free stream velocity are investigated. Convective boundary conditions have ...been used in the problem formulation. The solution for velocity and temperature are computed by applying the homotopy analysis method (HAM). The effects of emerging fluid parameters (ϵ), (δ) and Prandtl number (Pr) on the velocity and temperature are illustrated through graphs and tables for different values of λ. It is found that the boundary layer thickness is an increasing function of (ϵ) and decreasing function of (δ). However the temperature and thermal boundary layer thickness decrease when the values of (ϵ) and (δ) are increased.
Recently, bismuth ferrites have attracted great interest in the field of photocatalysis due to their magnetic nature and narrow band gap. Herein, nanohybrids of lanthanum (La) and manganese (Mn) ...co-doped BiFeO
3
(BLFMO)/graphene nanoplatelets (GNPs) have been synthesized. The hybrids were prepared by two different but simple and low-cost synthesis routes: (i) co-precipitation (namely the C-series), and (ii) hydrothermal (namely the H-series) methods. This article details a comparison of the C-series and H-series BLFMO/GNP nanohybrids based on their photocatalytic activity and band gap. The H-series nanohybrids showed a more crystalline structure, reduced band gap and less dye removal compared to the C-series nanohybrids. The enhanced dye removal (92%) of the C-series nanohybrids is attributed to their high surface area (55 m
2
g
−1
) due to GNP incorporation inside the BLFMO/GNP nanohybrids. The higher surface area enables more adsorption of dye molecules over the catalyst surface under dark conditions. In addition, the band gap of the BLFMO/GNP nanohybrids was reduced from 2.04 eV (pure BiFeO
3
) to 1.40 eV (BLFMO/GNPs) because of the presence of new donor energy levels with Mn loading. The calculated particle sizes from Scherrer's formula were 19.3-23.5 nm (C-series) and 22.5-26 nm (H-series). The estimated particle size calculated
via
transmission electron microscopy (TEM) is approximately 31 nm for the C-series nanohybrids. The graphene based nanohybrids significantly enhanced dye removal compared to pure BiFeO
3
(44%) under visible light irradiation. The low cost, easy preparation and higher catalytic activity of the BLFMO/GNP nanohybrids reported here make nanohybrids suitable candidates for practical applications.
This article details a comparison of the photocatalytic activity of La, Mn co-doped BiFeO
3
/GNP nanohybrids prepared by co-precipitation and hydrothermal methods.
Background
Preliminary evidence suggests intravenous ketamine has rapid effects on suicidal cognition, making it an attractive candidate for depressed patients at imminent risk of suicide. In the ...first randomized controlled trial of ketamine using an anesthetic control condition, we tested ketamine's acute effects on explicit suicidal cognition and a performance‐based index of implicit suicidal cognition (Implicit Association Test; IAT) previously linked to suicidal behavior.
Method
Symptomatic patients with treatment‐resistant unipolar major depression (inadequate response to ≥3 antidepressants) were assessed using a composite index of explicit suicidal ideation (Beck Scale for Suicidal Ideation, Montgomery‐Asberg Rating Scale suicide item, Quick Inventory of Depressive Symptoms suicide item) and the IAT to assess suicidality implicitly. Measures were taken at baseline and 24 hr following a single subanesthetic dose of ketamine (n = 36) or midazolam (n = 21), a psychoactive placebo agent selected for its similar, rapid anesthetic effects. Twenty four hours postinfusion, explicit suicidal cognition was significantly reduced in the ketamine but not the midazolam group.
Results
Fifty three percent of ketamine‐treated patients scored zero on all three explicit suicide measures at 24 hr, compared with 24% of the midazolam group (χ2 = 4.6; P = .03). Implicit associations between self‐ and escape‐related words were reduced following ketamine (P = .01; d = .58) but not midazolam (P = .68; d = .09). Ketamine‐specific decreases in explicit suicidal cognition were largest in patients with elevated suicidal cognition at baseline, and were mediated by decreases in nonsuicide‐related depressive symptoms.
Conclusions
Intravenous ketamine produces rapid reductions in suicidal cognition over and above active placebo. Further study is warranted to test ketamine's antisuicidal effects in higher‐risk samples.
The role of Se and various selenoproteins in male reproductive performance is reviewed. Development of male reproductive tissue requires an optimal level of Se in testis, and a small deviation, ...either deficiency or excess, leads to abnormal development. Selenium is a constituent of selenoproteins including GPx1, GPx3, mGPx4, cGPx4, and GPx5 that protect against oxidative damage to spermatozoa throughout the process of sperm maturation, whereas selenoproteins, such as mGPx4 and snGPx4, serve as structural components of mature spermatozoa. Thus Se and selenoproteins ensure viability of spermatozoa as well as providing protection against reactive oxygen species. Gene knock-out studies of selenoproteins revealed that their absence during spermatogenesis results in abnormal spermatozoa, which in turn affects semen quality and fertility. Deviation from the optimal quantities of dietary Se, both above or below, may cause multiple abnormalities of spermatozoa and affect motility and fertility. Libido may also be increased by Se. Dietary Se should be in optimal quantity to maintain reproductive function in males and to avoid infertility.
The defect formation mechanism in chemical vapor deposition grown single layer graphene devices has been investigated by increasing electron beam (e-beam) irradiation doses gradually up to 750e−/nm2. ...The evolution of D peaks in Raman spectra provides an evidence of strong lattice disorder due to e-beam irradiation. Particularly, the trajectory of D and G peak intensities ratio (ID/IG) suggests that the transformation of graphene from crystalline to the nanocrystalline and then towards amorphous form with increasing irradiation dose. The defect parameters were calculated by phenomenological model of amorphization trajectory for graphitic materials. The mobility decreasing gradually from ∼1200 to ∼80cm2/V s with gradual increase of irradiation dose, which implies the formation of localized states in e-beam irradiated graphene. The Dirac point is shifted towards negative gate voltage which indicates the n-doping in graphene with increasing e-beam irradiation dose.
Display omitted
A series of composite materials of general molecular formula (1−x) Na2SO4−(x) LDT was prepared by solid state reaction method. The phase structure and functionalization of these ...materials were defined by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) respectively. Differential thermal analysis (DTA) revealed that the hump of phase transition at 250°C has decreased while its thermal stability was enhanced. Scanning electron microscopy signifies the presence of improved rigid surfaces and interphases that are accountable for the high ionic conduction due to dispersion of LDT particles in the composite systems. Arrhenius plots of the conductance show the maximum conductivity, σ=4.56×10−4Scm−1 at 500°C for the x=0.4 composition with the lowest activation energy 0.34eV in the temperature range of 573–773K. The value of dielectric constant was decreased with increasing frequency and follows the usual trend.
PDF
