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In this article, the Ansys Workbench was used to carry out the finite element analysis of 15 kW wind turbine blades with different damaged positions and different damaged degrees. The results show that the change rate of natural frequency, displacement modes, and strain modes of the blades increased with the increase in the damage degree; the change rate of the natural frequency and displacement modes of the blade decreased with the increase in the speed, while the change rate of the strain modes increased; the change allocation ratio of the displacement modes and strain modes after the damage was more obvious at the damage location than other positions, which can be used to locate the damage position of the blade; the change allocation ratio of strain modes is higher than the change allocation ratio of displacement modes when the damage degree is the same, which means that the recognition effect of the strain modes is more significant than that of the displacement modes.

Urban parks can mitigate the urban heat island (UHI) and effectively improve the urban microclimate. In addition, quantifying the park land surface temperature (LST) and its relationship with park characteristics is crucial for guiding park design in practical urban planning. The study’s primary purpose is to investigate the relationship between LST and landscape features in different park categories based on high-resolution data. In this study, we identified the land cover types of 123 parks in Luoyang using WorldView-2 data and selected 26 landscape pattern indicators to quantify the park landscape characteristics. The result shows that the parks can alleviate UHI in most seasons, but some can increase it in winter. While the percentage of bare land, PD, and PAFRAC have a positive impact on LST, AREA_MN has a significant negative impact. However, to deal with the current urban warming trend, a compact, clustered landscape configuration is required. This study provides an understanding of the major factors affecting the mitigation of thermal effects in urban parks (UP) and establishes a practical and feasible urban park renewal method under the idea of climate adaptive design, which provides valuable inspiration for urban park planning and design.

Heavy metals and metalloids, in sludge and sediments, are environmental pollutants of concern with long-term negative effects on human and ecological health. In this study, sludge from biological treatment of municipal waste leachate was pyrolyzed into leachate sludge-derived biochar (LSDB) at 300°C to 900°C, comprising complex organic and inorganic (particularly heavy metals) species formed from heterogeneous chemical reactions. Based on different advanced material analyses, that is, Thermogravimetric Analysis (TGA), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis, this study revealed that mass loss and microstructural changes of LSDBs occurred primarily due to decomposition of volatiles, aromatic rings, carbonates, and hydroxides. The leaching behaviors of heavy metals from LSDBs were evaluated using the Synthetic Precipitation Leaching Procedure (SPLP). The final pH in SPLP increased from 7.5 to 12.5 with pyrolysis temperature. The pH increase favored the retention of heavy metals in the LSDBs due to the formation of low soluble precipitates at alkaline pH. The heavy metals and metalloids in the LSDBs were present as surface precipitates due to precipitation and cation exchange rather than surface complexation. The leaching contents of metals and metalloids, such as Cr, Cd, Ni, Pb, and As, were all below their respective maximum discharge standards for the first priority pollutants in China. PRACTITIONER POINTS: The pH increase favored the retention of heavy metals in the leachate sludge-derived biochar (LSDB). The heavy metals in the LSDB were present as surface precipitates due to precipitation and cation exchange rather than surface complexation. The heavy metals/metalloids concentration of LSDB (>600°C) in leachate was low and was likely safe for use.

The effect of urbanization on the urban thermal environment (UTE) has attracted increasing research attention because its significant effects on local weather and climate, and serious consequences for people. However, systematic study of the relationship between urbanization and UTE has been undertaken only to a limited extent. Using quantitative thermal remote sensing and multi-buffer ring method and multiple spatial scales method, here we analyze Landsat TM/ETM+ images of Zhengzhou in Central China acquired on four different dates in 2017 to investigate the spatiotemporal variations, trends, and driving force in the land surface temperature (LST). Our results showed that LST generally increased with urbanization intensity. This trend was extremely obvious in spring and summer, weak in winter, and slightly downward in autumn. Moreover, PLAND (e.g., percentage of impervious surface in a landscape) has the most significant effect on urban LST, and generally increases as the spatial scale becomes larger. In conclusion, the study recommends that urban planning in Zhengzhou should prioritize PLAND, especially at large spatial scales. These results provide a scientific reference for urban planners who are committed to the sustainable development of Zhengzhou City.

Here, NiMoO4 was successfully synthesized via a mild hydrothermal method combined with annealing treatment. The effects of nickel sources and Tween 80 on the morphology and electrochemical performance of NiMoO4 electrode for hybrid energy storage device were investigated in detail. When nickel sulfate as a nickel source, NiMoO4 exhibited a one-dimensional needle structure and reached the best specific capacity of 498 C g−1 at 1 A g−1. Moreover, the different dosages of Tween 80 all improved the morphology and capacity of one-dimensional needle NiMoO4. When the dosage was 0.005 mol, NiMoO4 nanorods formed a flower-like morphology and a higher specific capacity of 754 C g−1. Furthermore, we used the optimized NiMoO4 assembled a hybrid device which reached 68.36 Wh kg−1 at a power density of 923 W kg−1.

LiFe0.65Mn0.35PO4/C composites with porous structure have been successfully prepared through a facile sol-gel method. After comparison, the non-ionic surfactant polyvinylpyrrolidone (PVP) was selected as the best nitrogen source. The structures, morphologies, and electrochemical performances of the composites were characterized by XRD, XPS, SEM, charge/discharge tests, and electrochemical impedance spectroscopy. The LiFe0.65Mn0.35PO4/C composite which is decorated with suitable amount of PVP has higher discharge capacity and more stable cycling performance. The results show that in the voltage range of 2.5–4.5 V, the discharge capacities of 148, 149.3, 139.3, and 130 mAhg−1 in the amount of 20% PVP could be delivered at 0.1, 0.2, 0.5, and 1 C, respectively. A remarkable rate capability was exhibited with 87.84% capacity retention at 1 C rate. The composites owned an optimum performance with a high rate capacity of 146.8 mAhg−1 when it returns to 0.1 C after 40 cycles of discharge at different rates.

The exploration of high-performance supercapacitors (SCs) has attracted wide attention worldwide. Herein, iron cobalt oxide (FeCo2O4) nanocomposites were prepared by using soft-template and hydrothermal method. The prepared FeCo2O4 electrode material presented good dispersivity and had different flower-like structures and flocculent structures, which exhibited high capacitance and cyclic stability. Specially, the FeCo2O4 electrode with the usage of 0.5 g polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and none template agents showed high capacitance of 1231.1, 956.2, 1027.8, and 677.3 F g−1 at 1 A g−1. Furthermore, we used an optimized FeCo2O4 electrode material as the positive electrode, activated carbon (AC) as the negative electrode, and 6 M KOH solution as the electrolyte to assemble an asymmetric supercapacitor (ASC). The resulting ASC device exhibits a favorable energy density of 51.2 Wh kg−1 and a high power density of 775.4 W kg−1.

Li (Ni0.5Co0.25Mn0.25)1−xNbxO2 (x = 0, 0.005, 0.01, 0.02, 0.03) cathode material was synthesized by co-precipitation. X-ray diffraction spectroscopy (XRD) and scanning electron microscopy (SEM) were used to analyze the crystal structure characteristics and morphology of the powder. The charge and discharge test, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) were used to study the electrochemical properties of the battery in detail. XRD results show that Nb5+ substitution does not destroy the crystal structure, but it can enlarge the interplanar spacing, which is beneficial to the diffusion of lithium ions. The electrochemical properties of the material Li (Ni0.5Co0.25Mn0.25)0.99Nb0.01O2 are the best. The discharge specific capacity is 204.6, 186.0, 163.5, 141.6 mAh/g at 0.1C, 0.2C, 0.5C, and 1.0C, respectively. And the discharge specific capacity is as high as 174.1 mAh/g when returning to 0.1C again. After circulating 45 cycles at 0.1C, the capacity retention rate was 89.08%.

Energy is an important requirement for population growth, technological progress and urbanisation. Worldwide energy demand has been projected to increase 5-fold by 2100. Fulfilment of these energy requirements cannot be solely reliant on fossil fuels, such as oil, coal and natural gas, on account of their adverse environmental impacts and concomitant depletion of natural resources. As a result multiple approaches for generating alternative energy are being explored globally.In this review paper, focused on the viability of waste especially MSW being a source for bioenergy products such as methane gas, bio-enzyme, biofuel and bio-fertiliser production. This review also focuses on the environmental impacts of MSW, the effect of MSW pre-treatments and properties (physical and chemical) on bioenergy products production.

With the development of the electronic industry, the requirements for equipment are becoming higher and higher in recent years. In this paper, a 4-bit absolute value detector is designed to have a low delay and energy consumption. The detector is composed of MUX, an adder, and a comparator. By comparing the 4-bit input with the given threshold value, the result is output. Based on the logic effort theory, this paper calculates the logic effort and parasitic delay of each stage of the detector and uses the transmission gate logic to redesign the XOR gate, which greatly improves its performance. Through certain calculations and optimization, the delay and energy consumption of the detector is reduced. Finally, this paper realizes a relatively simple 4-bit absolute value detection circuit, which has a small number of transistors and greatly improves the performance of the circuit. At the same time, it has a certain reference value for the related circuit design.

Dependency on plastic commodities has led to a recurrent increase in their global production every year. Conventionally, plastic products are derived from fossil fuels, leading to severe environmental concerns. The recent coronavirus disease 2019 pandemic has triggered an increase in medical waste. Conversely, it has disrupted the supply chain of personal protective equipment (PPE). Valorisation of food waste was performed to cultivate C. necator for fermentative production of biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The increase in biomass, PHBV yield and molar 3-hydroxy valerate (3HV) content was estimated after feeding volatile fatty acids. The fed-batch fermentation strategy reported in this study produced 15.65 ± 0.14 g/L of biomass with 5.32 g/L of PHBV with 50% molar 3HV content. This is a crucial finding, as molar concentration of 3HV can be modulated to suit the specification of biopolymer (film or fabric). The strategy applied in this study addresses the issue of global food waste burden and subsequently generates biopolymer PHBV, turning waste to wealth.

Miscanthus is a fast-growing perennial grass that attracts significant attention for its potential application as a feedstock for bioethanol production. This report explores the difference in the lignocellulosic composition of various Miscanthus cultivars, including Miscanthus × giganteus cultivated at the same location (mainly Lincoln, UK). It also assesses the sugar release profiles and mineral composition profiles of five Miscanthus cultivars harvested over a growing period from November 2018 to February 2019. The results showed that Miscanthus × giganteus contains approximately 45.5% cellulose, 29.2% hemicellulose and 23.8% lignin (dry weight, w/w). Other cultivars of Miscanthus also contain high quantities of carbohydrates (cellulose 41.1–46.0%, hemicellulose 24.3–32.6% and lignin 21.4–24.9%). Pre-treatment of Miscanthus using dilute acid followed by enzymatic hydrolysis released 63.7–80.2% of the theoretical glucose content. Fermentation of a hydrolysate of Miscanthus × giganteus using Saccharomyces cerevisiae NCYC2592 produced 13.58 ± 1.11 g/L of ethanol from 35.13 ± 0.46 g/L of glucose, corresponding to a yield of 0.148 g/g dry weight Miscanthus biomass. Scanning electron microscopy was used to study the morphology of raw and hydrolysed Miscanthus samples, which provided visual proof of Miscanthus lignocellulose degradation in these processes. The sugar release profile showed that a consequence of Miscanthus plant growth is an increase in difficulty in releasing monosaccharides from the biomass. The potassium, magnesium, sodium, sulphur and phosphorus contents in various Miscanthus cultivars were analysed. The results revealed that these elements were slowly lost from the plants during the latter part of the growing season, for a specific cultivar, until February 2019.

Zinc cobalt oxide (ZnCo2O4) is successfully achieved by a simple hydrothermal process and adjusting the annealing temperature, utilizing sodium dodecyl sulfate (SDS), polyvinylpyrrolidone (PVP), cetyltrimethyl ammonium bromide (CTAB), and polyvinyl alcohol (PVA) as template agents. The prepared ZnCo2O4 exhibits a different morphological structure by adding a templating agent, which exhibits high capacitance and cycle stability. Specially, the ZnCo2O4 electrode using 1 g of PVP exhibited a superior performance with a high specific capacity of 1527.2 F g−1 at a current density of 1 A g−1 and 1204 F g−1 at 10 A g−1. In addition, P-ZCO was used as the positive electrode, and activated carbon (AC) was used as the negative electrode to assemble an asymmetric supercapacitor device. It has an energy density of 69.2 Wh kg−1 at a power density of 774.6 W kg−1, and a retention rate of 77% at a current density of 10 A g−1, which exhibits excellent performance.

Inhibitor tolerance is one of the key challenges in lignocellulosic bioethanol production. The presence of inhibitors in a lignocellulosic hydrolysate induces stress in microorganisms and thus reduces bioethanol synthesis efficiency. In this study, 166 marine yeasts isolated from different marine environments were compared with 78 terrestrial yeasts for their tolerance to inhibitory compounds such as acetic acid, formic acid, furfural, vanillin and salt, which are commonly found in hydrolysates derived from lignocellulosic materials. Marine yeasts showed higher tolerance to all the inhibitors tested than terrestrial yeasts. The most tolerant marine yeast was Wickerhamomyces anomalus M15 which had IC50 values of 10.7% (w/w) and 83.9 mM for salt and acetic acid, respectively, while those for an industrial terrestrial yeast Saccharomyces cerevisiae NCYC2592 were 6.0% (w/w) and 75.9 mM, respectively.Statistical analysis revealed that marine yeast clustered separately from terrestrial yeast. In fermentation, using simulated wheat straw hydrolysates containing inhibitors and prepared using seawater, three selected marine yeasts Saccharomyces cerevisiae AZ65, W. anomalus M15, and Candidamembranifaciens M2 produced 23–24 g L1 bioethanol from 60 g L1 glucose, while terrestrial yeast Saccharomyces cerevisiae produced only 12.5 g L1 bioethanol. Marine yeasts were significantly more tolerant to the presence of inhibitory compounds and are phenotypically distinct from terrestrial yeasts.Significantly, a higher quantity of bioethanol was obtained in fermentation using selected marine yeasts with media containing inhibitory compounds. The study has highlighted the potential of finding microorganisms with industrially favourable characteristics in marine ecosystems and other adverse and challenging environments

This review introduces a new approach of completely marine based bioethanol production by analyzing and evaluating the recent trends in bioethanol fermentations using algae, marine microorganisms and the replacement of freshwater with seawater. Both macroalgae and microalgae have been successfully used for bioethanol production. Marine yeasts showed excellent tolerance to salt and inhibitors, and fit for seawater fermentation. The combination of marine biomass, marine microorganism and seawater has a potential for a greener bioethanol production.

Infantile hemangioma (IH) is the most common benign vascular tumor resulting from the hyper-proliferation of vascular endothelial cells. In treatment of various tumors including IH, β-elemene, a compound extracted from Rhizoma zedoariae, has been reported to have anti-tumor effect. However, the underlying mechanisms of β-elemene in hemangioma have remained uninvestigated. In this presented study, functional analysis showed that low concentrations of β-elemene promoted the proliferation, migration and tube formation of human hemangioma endothelial cells (HemECs), while high concentrations of β-elemene produced inhibitory effects. Further, we also found that angiotensin-converting enzyme 2 (ACE2) expression was down-regulated at both mRNA and protein levels, while hypoxia-inducible factor-1 alpha (HIF-1-α) was up-regulated in infantile hemangiomas tissues and HemECs at both mRNA and protein levels. This result suggested that ACE2 and HIF-1-α play roles in IH. ACE2 expression was down-regulated with the treatment of β-elemene at different dosage point. Interestingly, the expression of Vascular endothelial growth factor-A (VEGFA) increased with treatment of low concentrations of β-elemene in HemECs, in contrary, the expression of VEGFA expression decreased with treatment of high concentrations of β-elemene. Moreover, if the concentration of β-elemene reached 40 μg/ml or higher, the expression of HIF-1-α decreased. Taken together, our data indicated that the different effects of β-elemene on the proliferation, migration and angiogenesis of hemangioma at different concentrations: The ACE2 signaling pathway dominates with treatment of low concentrations of β-elemene, stimulating the expression of downstream VEGFA to promote the angiogenesis of hemangioma; under the condition of high concentrations of β-elemene, the HIF-1-α signaling pathway inhibits the expression of VEGFA and further inhibits the angiogenesis of hemangioma.

Alginate is an attractive marine resource-based biopolymer, which has been widely used in pharmaceutical, food and textile industries. This paper reviewed the latest development of the conventional and alternative processes for alginate extraction from brown seaweed. To improve extraction yield and product quality, various studies have been carried out to optimize the operation condition. Based on literature survey, the most commonly used protocol is soaking milled seaweed in 2% (w/v) formaldehyde, overnight, solid loading ratio of 1:10–20 (dry weight biomass to solution), then collecting the solid for acid pre-treatment with HCl 0.2–2% (w/v), 40–60 °C, 1:10–30 ratio for 2–4 h. Next, the solid residue from the acid pre-treatment is extracted using Na2CO3 at 2–4% (w/v), 40–60 °C, 2–3 h, 1:10–30 ratio. Then the liquid portion is precipitated by ethanol (95%+) with a ratio of 1:1 (v/v). Finally, the solid output is dried in oven at 50–60 °C. Novel extraction methods using ultrasound, microwave, enzymes and extrusion improved the extraction yield and alginate properties, but the financial benefits have not been fully justified yet. To improve the sustainable production of alginate, it is required to promote seaweed cultivation, reduce water footprint, decrease organic solvent usage and co-produce alginate with other value-added products.

The accumulation of organic waste, such as wasted food, municipal solid waste, food processing waste, agriculture residue, and forest waste, causes worldwide concerns due to limit landfill spaces and tightened rules on incineration. In recent years, various strategies have been explored for the reduction of organic waste materials and to recycle and reuse these materials for the production of value-added products. One of the emerging approaches is the conversion of organic waste into biofertilizer. This chapter reviews recent progress in the area regarding the conversion various organic waste streams into biofertilizers, including wasted food, municipal solid waste, food processing waste, and agriculture residue. Reports on the field tests of these biofertilizers are reviewed as well.

Textile waste is one type of municipal solid waste growing rapidly in recent years. In Hong Kong, 306 t of textile waste were produced daily in 2015 and more than 90% of these ended up in landfill. This is the first paper which utilizes textile wastes as substrate for cellulase production via submerged fungal fermentation, the resultant fungal cellulase was subsequently utilised in textile waste hydrolysis for recovery of glucose and polyester. Trichoderma reesei ATCC 24449 was selected with the highest cellulase activity (18.75 FPU/g) after cultivation using textile blending cotton/polyester 40/60 as substrate. Cellulase production was upscaled in a 5-L bioreactor and the resultant cellulase was used in textile waste hydrolysis. Glucose recovery yield of 41.6% and 44.6% were obtained using fungal cellulase and commercial cellulase, respectively. These results suggest the proposed process has a great potential in treating textile waste and facilitating the recovery of glucose and polyester as value-added products.

Abundant textile waste has raised increasing concerns worldwide in developing novel circular textiles approach. This study investigated the optimum cellulase production from textile waste by Aspergillus niger CKB. Textile wastes consisting of cotton and polyester in various ratios were used as low-cost feedstock. Three types of cultivation media were compared in solid state fermentation and Mandels medium with yeast extract selected due to its superior cellulase production. Conditions including moisture, pH, inoculum size and organic nitrogen were evaluated and optimised via response surface methodology. Supplementary carbon sources and cellulase inducers were also employed to enhance fungal growth and cellulase production. The results indicated that the optimised fermentation method significantly improved cellulase producing efficiency and enzyme activity by 88.7% and 25.8%, respectively. The maximum cellulase activity reached 1.56 FPU g−1 in 6 days. The outcomes led to the efficient recovery of glucose and polyester, which could contribute to a closed-loop recycling strategy for the textile industry, and enable the transition to an advanced circular textiles economy.

Worldwide significant amounts of food waste are generated daily causing serious environmental issues, occupying land and requiring expenditure of resources for its treatment. A smart method for handling this food waste problem is the development of novel processes targeting the conversion of this waste into value added products. Although valorization of food waste to biofuels, biochemicals and bio-polymers have been widely investigated, the utilization of food waste streams into biofertiliser has not been intensively reviewed. Conversion of food waste, especially agriculture residues into biofertiliser would reduce its environmental impact, improve nutrition levels of the soil, decrease requirements for synthetic chemical fertiliser and have a direct benefit on food production. This paper reviews recent progress in the field regarding the production of biofertiliser from food waste, using anaerobic digestion, aerobic composting, chemical hydrolysis, in situ degradation and direct burning methods. This review also highlights the latest field applications of biofertiliser derived from various food waste streams. It confirms that the technology for the conversion of food waste to biofertilisers is viable, but the production efficiency could be improved with better process control strategies, strict quality controls, development of a smart product distribution system and adoption of advanced technologies. Field tests have indicated that biofertilisers which are obtained in proper managed AD plants are safe and could partially replace the use of chemical fertilisers in field application.

Treatment of Municipal Solid Waste (MSW) becomes an increasing problem worldwide; however, MSW contains high lignocellulosic content that can be further processed for the generation of electricity, transportation fuel and other commercially important products. This study aims to explore the possibility of hydrolyzing MSW into a sugar solution, which could then be fermented into liquid biofuels, such as bioethanol. Two commercial cellulase enzymes, Cellic® CTec2, and a fresh prepared fungal filtrate were used to hydrolyse MSW. Results revealed that CTec2 displayed the best hydrolysis efficiency. Use of an alkali pre-treatment on MSW before enzymatic hydrolysis failed to show any improvement in terms of release of sugars, an assessment of the efficacy of addition of surfactants revealed that addition of tween 80 or polyethylglycol had a no significant effect on release of sugars. Results revealed that by increasing the solid liquid ratio the amount of glucose increased, Data generated by this study was analysed using design expert stat program.