Lithium‐sulfur cells are attractive energy‐storage systems because of their high energy density and the electrochemical utilization rates of the high‐capacity lithium‐metal anode and the low‐cost ...sulfur cathode. The commercialization of high‐performance lithium–sulfur cells with high discharge capacity and cyclic stability requires the optimization of practical cell‐design parameters. Herein, a carbon structural material composed of a carbon nanotube skeleton entrapping conductive graphene is synthesized as an electrode substrate. The carbon structural material is optimized to develop a high‐loading polysulfide cathode with a high sulfur loading capacity (6–12 mg cm−2), rate performance (C/10–C/2), and cyclic stability for 200 cycles. A thin lithium anode based on the carbon structural material is developed and exhibits long lithium stripping/plating stability for ≈2500 h with a lithium‐ion transference number of 0.68. A lean‐electrolyte lithium–sulfur full cell with a low electrolyte‐to‐sulfur ratio of 6 µL mg−1 is constructed with the designed high‐loading polysulfide cathode and the thin lithium anode. The integration of all the critical cell‐design parameters endows the lithium–sulfur full cell with a low negative‐to‐positive capacity ratio of 2.4, while exhibiting stable cyclability with an initial discharge capacity of 550 mAh g−1 and 60% capacity retention after 200 cycles.
A carbon structural material with an optimal graphene/carbon‐nanotube configuration is designed to serve as a high‐loading polysulfide cathode and a thin lithium anode in a lean‐electrolyte lithium–sulfur battery full cell simultaneously featuring a high sulfur loading (6 mg cm−2), a low electrolyte‐to‐sulfur ratio (6 µL mg−1), a low negative‐to‐positive capacity ratio (2.4), and a long cycle life (200 cycles)..
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Semiconductor materials have been shown to have good photocatalytic behavior and can be utilized for the photodegradation of organic pollutants. In this work, three-dimensional flower-like SnS₂ (tin ...sulfide) was synthesized by a facile hydrothermal method. Core-shell structured SiO₂@α-Fe₂O₃ nanocomposites were then deposited on the top of the SnS₂ flowers. The as-synthesized nanocomposites were characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV⁻Vis Spectroscopy, Brunauer⁻Emmett⁻Teller (BET) surface area analysis, and photoluminescence (PL) spectroscopy. The photocatalytic behavior of the SnS₂-SiO₂@α-Fe₂O₃ nanocomposites was investigated by observing the degradation of methylene blue (MB). The results show an effective enhancement of photocatalytic activity for the degradation of MB especially for the 15 wt % SiO₂@α-Fe₂O₃ nanocomposites on SnS₂ flowers.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The mechanisms involved in premixed magnesium and hydrogen hybrid and synthetic MgH2 dust cloud explosions were investigated. The results revealed that trace amounts of H2 in Mg explosions can ...markedly increase explosion severity. Furthermore, H2 addition can weaken the influence of oxygen deficiency on Mg explosion. Moreover, the explosion intensity of synthetic MgH2 was far stronger than that of premixed Mg/H2 mixture or Mg alone because the vacancy defects in Mg and H atoms can form after dehydrogenation of MgH2, which caused that Mg and H2 are prone to oxidation and nitrification in air atmosphere at a low temperature, thereby promoting the explosion. This demonstrates that the explosion risk of MgH2 (even other H2 storage materials) is related to its H2 storage capacity and dehydrogenation temperature. Therefore, for H2 storage materials, the better H2 storage performances can exhibit higher explosion risks.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Community-scale composting, which can be conducted by the local council or a waste management company, is an effective starting point to divert food waste from landfill, especially for developing ...countries. This paper successfully demonstrates the feasibility of a community-scale food waste composting system, using the University of Nottingham Malaysia as the case study. The method selected is open-air static pile, using food waste as the substrate and leaf-litter as the bulking agent. The composting model presented in this study is also applicable to other organic wastes. The two feedstocks are mixed at a food waste-to-leaves weight ratio of 4: 1 to result in an initial moisture level of 63% and carbon-to-nitrogen ratio of 27. The composting process can be completed in 7 months, yielding about 30 wt % (on dry basis) of compost from the total organic feedstock. The finished compost is shown to meet Malaysia’s organic fertiliser standard, thus demonstrating the feasibility of this low-cost technology. Economic analysis showed that substituting chemical fertilisers with the organic compost produced in-house is a viable option, and that for Malaysia, the composting system would be able to self-sustain financially only when the landfilling cost is increased 2.3 times. The life-cycle assessment showed that using composting to replace landfill for food waste, as well as substituting chemical fertilisers with the organic compost produced, can greatly reduce the environmental impacts, especially on global warming, ecotoxicity, eutrophication and fossil fuel depletion. In order to promote the widespread application of composting for organic wastes, multi-actor partnerships are essential to link governments, organisations and households in working toward a circular economy.
Display omitted
•A community-scale organic waste composting system is presented.•It takes 7 months to produce compost from food waste, with leaves as bulking agent.•The compost yield is 30% and its quality meets the organic fertiliser standards.•Socio-cultural, economic, environmental and technical barriers were evaluated.•This system could be replicated and scaled up easily for widespread applications.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Stress granules (SGs) are nonmembranous organelles that are dynamically assembled and disassembled in response to various stressors. Under stressed conditions, polyadenylated mRNAs and translation ...factors are sequestrated in SGs to promote global repression of protein synthesis. It has been previously demonstrated that SG formation enhances cell survival and stress resistance. However, the physiological role of SGs in organismal aging and longevity regulation remains unclear. In this study, we used TIAR‐1::GFP and GTBP‐1::GFP as markers to monitor the formation of SGs in Caenorhabditis elegans. We found that, in addition to acute heat stress, SG formation could also be triggered by dietary changes, such as starvation and dietary restriction (DR). We found that HSF‐1 is required for the SG formation in response to acute heat shock and starvation but not DR, whereas the AMPK‐eEF2K signaling is required for starvation and DR‐induced SG formation but not heat shock. Moreover, our data suggest that this AMPK‐eEF2K pathway‐mediated SG formation is required for lifespan extension by DR, but dispensable for the longevity by reduced insulin/IGF‐1 signaling. Collectively, our findings unveil a novel role of SG formation in DR‐induced longevity.
In addition to heat stress, starvation and dietary restriction (DR) can activate stress granule (SG) formation in Caenorhabditis elegans. HSF‐1 and AMPK are two key regulators for the SG formations. HSF‐1 is required for the SG formation in response to acute heat shock and starvation but not DR, whereas the AMPK‐eEF2K pathway is required for starvation and DR‐induced SG formation but not heat shock. Furthermore, AMPK‐mediated SG formation contributes to DR‐induced longevity.
Full text
Available for:
DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Cellulose nanocrystals (CNCs) have attracted tremendous attention because of their excellent chemical and physical properties and due to their renewability and sustainability. This material can be ...extracted from agricultural by-products such as rice straw, banana tree, or bagasse. Rice straw was selected as the raw material in this study. Initially, a large amount of lignin must be removed by an alkaline process to obtain a slurry. Thereafter, a green bleaching process can be used to remove the remaining lignin in the slurry. An UV-emitting diode with 365 nm wavelength assisted the oxidation reaction of the H
2
O
2
solution without the use of chlorine-containing chemical bleach. The reaction required only 2.5 h to obtain high-purity cellulose and successfully enhanced the yield. Transmission electron microscopy images showed that the CNCs from rice straw were ~ 100 nm long and 10–15 nm wide. The crystalline index and degradation temperature of CNCs were 83.8% and 257 °C, respectively.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background and Purpose
Heparanase is the only confirmed endoglycosidase that cleaves heparan sulfate (HS), a ubiquitous glycosaminoglycan with various essential roles in multiple pathological ...processes. Thus, the development of heparanase inhibitors has become an attractive strategy for drug discovery, especially in tumour therapy, in which HS mimetics are the most promising compounds. The various biological effects of heparanase also suggest a role for HS mimetics in many non‐cancer indications, such as type 1 diabetes. However, the potential benefits of HS mimetics in obesity‐related type 2 diabetes have not been elucidated.
Experimental Approach
In this study, we investigated muparfostat (PI‐88), a developed HS mimetic currently enrolled in Phase III clinical trials, in obese mouse models and in vitro cultured murine hepatocytes.
Key Results
Daily administration of muparfostat for 4 weeks caused hyperlipidaemia and aggravated hepatic steatosis in obese mice models, but not in lean animals. In cultured hepatocytes, muparfostat did not alter lipid accumulation. Acute tests suggested that muparfostat binds to lipoprotein lipase in competition with HS on vascular endothelial cell surfaces, thereby reducing the degradation of circulating triglycerides by lipoprotein lipase and subsequent uptake of fatty acids into vascular endothelial cells and causing hyperlipidaemia. This hyperlipidaemia aggravates hepatic steatosis and causes liver injury in muparfostat‐treated obese mice.
Conclusions and Implications
The binding activity of HS mimetics to lipoprotein lipase should be investigated as an additional pharmacological effect during heparanase inhibitor drug discovery. This study also provides novel evidence for an increased risk of drug‐induced liver injury in obese individuals.
Full text
Available for:
BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
During the injection molding of molten polymers, the control strategy is switched from speed control to pressure control at the filling‐to‐packing (V/P) switchover point. V/P switchover influences ...part quality and process stability. V/P switchover timing traditionally depends on the degree of volumetric filling of molten polymer in the cavity and is limited to obtain a smooth and repeatable pressure curve for each injection, indicating consistent part quality. Repeatability is affected by the V/P switchover point, injection speed, holding pressure, and holding time. This study clarifies the effect of the injection speed, V/P switchover point, and first‐stage holding pressure setting on cavity pressure curves and injection molding quality. These factors were optimized and verified through the injection molding of integrated circuit trays. The experimental results indicate that adjusting the rear speed of filling stage, V/P switchover point, and first‐stage holding pressure, can yield the ideal pressure curve and improve process stability. Compared with the initial process parameter setting, part warpage was reduced by 40% from 0.042 to 0.025 mm, deviation of part width at the end of the filling pattern was reduced by 54% from 0.024 to 0.011 mm, and width range was reduced by 50% from 0.006 to 0.003 mm.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Neural circuit function requires mechanisms for controlling neurotransmitter release and the activity of neuronal networks, including modulation by synaptic contacts, synaptic plasticity, and ...homeostatic scaling. However, how neurons intrinsically monitor and feedback control presynaptic neurotransmitter release and synaptic vesicle (SV) recycling to restrict neuronal network activity remains poorly understood at the molecular level. Here, we investigated the reciprocal interplay between neuronal endosomes, organelles of central importance for the function of synapses, and synaptic activity. We show that elevated neuronal activity represses the synthesis of endosomal lipid phosphatidylinositol 3‐phosphate PI(3)P by the lipid kinase VPS34. Neuronal activity in turn is regulated by endosomal PI(3)P, the depletion of which reduces neurotransmission as a consequence of perturbed SV endocytosis. We find that this mechanism involves Calpain 2‐mediated hyperactivation of Cdk5 downstream of receptor‐ and activity‐dependent calcium influx. Our results unravel an unexpected function for PI(3)P‐containing neuronal endosomes in the control of presynaptic vesicle cycling and neurotransmission, which may explain the involvement of the PI(3)P‐producing VPS34 kinase in neurological disease and neurodegeneration.
Synopsis
Neural circuit function requires mechanisms for the control of neurotransmitter release. We Here, presynaptic vesicle cycling and neurotransmission are found to be feedback‐regulated by the endosomal lipid phosphatidylinositol 3‐phosphate (PI(3)P).
Neuronal activity inhibits endosomal PI(3)P synthesis in neurons.
Reduced PI(3)P levels repress neurotransmission and impair vesicle recycling.
Loss of PI(3)P triggers calpain and Cdk5 activation, a key negative control switch for neurotransmission.
PI(3)P loss prevents hyperactivity of neuronal networks independent of synaptic inhibition.
Enhanced neuronal activity lowers endosomal PI(3)P levels to perturb synaptic vesicle endocytosis and neuronal activity via Calpain 2‐mediated Cdk5 activation.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Pharmaceutical residues are emerging pollutants in the aquatic environment and their removal by conventional wastewater treatment methods has proven to be ineffective. This research aimed to develop ...a three-dimensional reduced graphene oxide aerogel (rGOA) for the removal of diclofenac in aqueous solution. The preparation of rGOA involved facile self-assembly of graphene oxide under a reductive environment of L-ascorbic acid. Characterisation of rGOA was performed by Fourier transform infrared, scanning electron microscope, transmission electron microscopy, nitrogen adsorption-desorption, Raman spectroscopy and X-ray diffraction. The developed rGOA had a measured density of 20.39 ± 5.28 mg/cm3, specific surface area of 132.19 m2/g, cumulative pore volume of 0.5388 cm3/g and point of zero charge of 6.3. A study on the simultaneous interactions of independent factors by response surface methodology suggested dosage and initial concentration as the dominant parameters influencing the adsorption of diclofenac. The highest diclofenac adsorption capacity (596.71 mg/g) was achieved at the optimum conditions of 0.25 g/L dosage, 325 mg/L initial concentration, 200 rpm shaking speed and 30 °C temperature. The adsorption equilibrium data were best fitted to the Freundlich model with correlation coefficient (R2) varying from 0.9500 to 0.9802. The adsorption kinetic data were best correlated to the pseudo-first-order model with R2 ranging from 0.8467 to 0.9621. Thermodynamic analysis showed that the process was spontaneous (∆G = − 7.19 to − 0.48 kJ/mol) and exothermic (∆H = − 12.82 to − 2.17 kJ/mol). This research concluded that rGOA is a very promising adsorbent for the remediation of water polluted by diclofenac.
•3D graphene aerogel was assembled by chemical reduction and freeze drying.•Optimisation by response surface methodology yielded highest q of 596.71 mg/g.•Optimum states: 0.25 g/L dosage, 325 mg/L concentration, 200 rpm shaking, 30 °C.•Adsorption equilibrium was best described by the Freundlich model.•Adsorption kinetic was best fitted to the pseudofirst-order kinetic model.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
