The use of seawater desalination technology to solve water shortages in energy- and resource-scarce regions has attracted widespread attention worldwide. In this paper, the performance of a closed-cycle humidification−dehumidification desalination system with a heat pump was experimentally investigated. The system is a closed-cycle system, which includes humidifiers, a heat pump, dehumidifiers, and an air heat exchanger. The heat pump is used by the system to carry energy. The effects of different parameters on the system performance were studied. Scale and economic analyses of the system were conducted to explore the application prospects of the system. The maximum gained output ratio of the system was 4.82. The maximum freshwater production was 960 kg/h, and the cost per kilogram of freshwater was USD 0.03, which are more considerable compared with other systems. This system provides an effective way to save energy in remote areas with energy shortages and freshwater resource shortag... [more]

In this paper, a set of silicon hybrid phenolic resins (SPF) with high Si-content were prepared by mixing phenolic resins with self-synthesized silicon resins. In order to obtain the nanoscale phase structure, condensation degree and the amount of Si-OH groups in silicon resins were controlled by the amount of inhibitor ethanol in the hydrolytic condensation polymerization of siloxane. Increasing the amount of ethanol resulted in more silanol groups and a lower degree of condensation for silicon resins, which then led to more formation of Si-O-Ph bonds in hybrid resin and improved compatibility between silicon resin and phenolic resin. When 400% ethanol by weight of siloxane was used in the sample SPF-4, nanoscale phase separation resulted. The residual weight of the cured SPF-4 at 1000 °C (R1000) significantly increased compared to pure phenolic resins. The result of the oxyacetylene flame ablation and the Cone Calorimeter test confirmed the improved ablative property and flammability... [more]

Among all minerals, iron is one of the elements identified early by human beings to take advantage of and be used. The role of iron in human life is so great that it made an era in the ages of humanity. Pure iron has a shiny grayish-silver color, but after combining with oxygen and water it can make a colorful set of materials with divergent properties. This diversity sometimes appears ambiguous but provides variety of applications. In fact, iron can come in different forms: zero-valent iron (pure iron), iron oxides, iron hydroxides, and iron oxide hydroxides. By taking these divergent materials into the nano realm, new properties are exhibited, providing us with even more applications. This review deals with iron as a magic element in the nano realm and provides comprehensive data about its structure, properties, synthesis techniques, and applications of various forms of iron-based nanostructures in the science, medicine, and technology sectors.

In order to understand the characteristics of the spray field of a dust suppression nozzle and provide a reference for dust nozzle selection according to dust characteristics, a three-dimensional phase Doppler particle analyzer (PDPA) spray measurement system is used to analyze the droplet size and velocity characteristics in a spray field, particularly the joint particle size−velocity distribution. According to the results, after the ejection of the jet from the nozzle, the droplets initially maintained some velocity; however, the distribution of particles with different sizes was not uniform. As the spray distance increased, the droplet velocity decreased significantly, and the particle size distribution changed very little. As the distance increased further, the large droplets separated into smaller droplets, and their velocity decreased rapidly. The distributions of the particle size and velocity of the droplets then became stable. Based on the particle size-velocity distribution c... [more]

Facing significant natural resource consumption, environmental degradation, and climate warming, governments and international organizations have increased their focus on ecological modernization, green growth, and low carbon development, with various sustainable development strategies [...]

Nanotechnology addresses numerous environmental problems such as wastewater treatment. Ground water, surface water and wastewater that is contaminated by toxic organic, inorganic solutes and pathogenic microorganisms can now be treated through the application of nanotechnology. The study reports iron@copper (Fe@Cu) nanoparticles, iron nanoparticles (FeNPs) and copper nanoparticles (CuNPs) synthesized using a bioflocculant in a green approach technique. Characterization of the as-synthesized materials was achieved using analytical techniques such as Fourier transform-Infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), UV-Vis spectroscopy (UV-Vis) and X-ray diffraction (XRD). The presence of hydroxyl (−OH) and amine (−NH2) groups was shown by FT-IR spectroscopy studies and the as-synthesized material was shown to be thermostable. Elements such as oxygen, carbon, iron and copper were found to be abund... [more]

Double-suction centrifugal pumps form an integral part of power plant systems in maintaining operational stability. However, there has been a common problem of achieving a better cavitation performance over a wider operating range because the traditional approach for impeller design often leads to the design effect not meeting the operational needs at off-design conditions. In addressing the problem, an optimization scheme was designed with the hub and shroud inlet angles of the double-suction impeller to minimize the suction performance at non-design flow conditions. A practical approach that speeds up the cavitation simulation process was applied to solve the experimental design, and a multi-layer feed forward artificial neural network (ANN) was combined with the non-dominated sorting genetic algorithm II to solve the multi-objective problem into three-dimensional (3D) Pareto optimal solutions that meet the optimization objective. At the design point, the suction performance was impr... [more]

The main roles of fault detection and diagnosis (FDD) for industrial processes are to make an effective indicator which can identify faulty status of a process and then to take a proper action against a future failure or unfavorable accidents. In order to enhance many process performances (e.g., quality and throughput), FDD has attracted great attention from various industrial sectors. Many traditional FDD techniques have been developed for checking the existence of a trend or pattern in the process or whether a certain process variable behaves normally or not. However, they might fail to produce several hidden characteristics of the process or fail to discover the faults in processes due to underlying process dynamics. In this paper, we present current research and developments of FDD approaches for process monitoring as well as a broad literature review of many useful FDD approaches.

The diesel engine is one of the solutions to slow down fossil fuel depletion due to its high efficiency. However, its high pollutant emission limits its usage in many fields. To improve its efficiency and emissions, a conventional mechanical fuel injection system (MFI) was be replaced with common rail direct injection (CRDI) system for the purpose of this study. In this way, injection parameters such as injection timing, injection pressure and multiple injection schemes can be tuned to enhance the engine performance. The rail pressure and engine speed response of the modified diesel engine was tested. It was found that by advancing the start of injection timing (SOI) timing or increasing the rail pressure, the brake torque generated can be increased. Multiple injection schemes can be implemented to reduce the peak heat release rate (HRR). Post injection was observed to increase the late combustion HRR. The maximum pressure rise rate (PRR) can be reduced by applying pilot injection. Fur... [more]

Graphene nanofluids have attracted the attention of many researchers because of a variety of remarkable properties such as extraordinary electronic transport properties, high thermal conductivity, and large specific surface areas. This paper investigates the shape effects of nanoparticles on the Marangoni boundary layer of graphene−water nanofluid flow and heat transfer over a porous medium under the influences of the suction parameter. The graphene−water nanofluid flow was contained with various shapes of nanoparticles, namely sphere, column, platelet, and lamina. The problem is modeled in form of partial differential equations (PDES) with boundary conditions. The governing transport equations are converted into dimensionless form with the help of some suitable nondimensional variables. The solution of the problem was found numerically using the NDSolve technique of Mathematica 10.3 software. In addition, the numerical solutions were also compared with analytical results. The homotopy... [more]

In this paper, a method based on the partial similarity principle is presented to improve the aerodynamic design with low cost and high accuracy for a 1-1/2 axial compressor. By means of this method, during the process of a similar design, the machine Mach number and flowrate coefficient are maintained. The flow similarity between the prototype and its large-scaled alternative was observed, according to a detailed analysis of flow fields of rotor and stator. As well, the relative discrepancies of isentropic efficiency and pressure ratio between two models are 1.25% and 0.4% at design point, respectively. Besides, their performance curves agreed very well in the whole operating range. Moreover, it was also found that the flow similarity between the two models can be maintained under unsteady working conditions. Thereafter, in order to investigate the impact of stability optimization method on the similarity principle, casing treatment with single circumferential groove was applied to th... [more]

The complex data characteristics collected in Industry 4.0 cannot be efficiently handled by classical Six Sigma statistical toolkit based mainly in least squares techniques. This may refrain people from using Six Sigma in these contexts. The incorporation of latent variables-based multivariate statistical techniques such as principal component analysis and partial least squares into the Six Sigma statistical toolkit can help to overcome this problem yielding the Multivariate Six Sigma: a powerful process improvement methodology for Industry 4.0. A multivariate Six Sigma case study based on the batch production of one of the star products at a chemical plant is presented.

Rapeseed oil of high acidity, an agricultural industry by-product unsuitable for food, was used as an inexpensive raw material for the production of biodiesel fuel. The use of rapeseed oil that is unsuitable for food and lipase as a catalyst makes the biodiesel production process environmentally friendly. Simultaneous oil extraction and in situ transesterification using diesel as an extraction solvent was investigated to obtain a diesel-biodiesel blend. The diesel and rapeseed oil blend ratio was 9:1 (w/w). The enzymatic production of biodiesel from rapeseed oil with high acidity and methanol using eleven different lipases as biocatalysts was studied. The most effective biocatalyst, lipase—Lipozyme TL IM (Thermomyces lanuginosus), which is suitable for in situ transesterification—was selected, and the conversion of rapeseed oil into fatty acid methyl ester was evaluated. The influence of the amount of methanol and lipase, the reaction temperature and the reaction time were investigated... [more]

This study investigated the degradation of the herbicides diquat (DQ) and paraquat (PQ) by a solar photo-Fenton process that is mediated by Fe(III)-oxalate complexes at circumneutral pH = 6.5 in compound parabolic collectors (CPC)-type reactors. The photo-Fenton process operates efficiently at acidic pH; however, circumneutral operation was key to overcome drawbacks, such as acidification and neutralization steps, reagent costs, and the environmental footprint of chemical auxiliaries. This work revealed a remarkable reduction of total organic carbon for PQ (87%) and DQ (80%) after 300 min (at ca. 875 kJ L−1). Phytotoxicity assays confirmed that the treatment led to a considerable increase in the germination index for DQ (i.e., from 4.7% to 55.8%) and PQ (i.e., from 16.5% to 59.7%) using Cucumis sativus seeds. Importantly, treatment costs (DQ = USD$8.05 and PQ = USD$7.72) and the carbon footprint of the process (DQ = 7.37 and PQ = 6.29 kg CO2-Eqv/m3) were within the ranges that were rep... [more]

The copper accumulation ability and its impact on the glucosinolate content of the garden candytuft were studied. Different copper sources (adsorbents or solution) were used. Generally, the seedlings copper uptake from the adsorbents was in the amount needed for its growth and development with the beneficial or no impact on the glucosinolate content. The lowest copper concentration was detected in the total seedlings biomass which grew in the humus with the addition of Cu-exchanged zeolite NaX (27.88 μg g−1 DW) having glucosinolate content of 9757.81 µg g−1 DW (23.86 µmol g−1 DW). The highest copper concentration among all the garden candytuft samples was detected in the seedlings watered with CuSO4∙5H2O solution (514.63 μg g−1 DW) with a sharp decrease of the glucosinolate content 3103.33 µg g−1 DW (7.59 µmol g−1 DW). Based on the results obtained, the garden candytuft can be considered as a copper accumulator plant.

The development of fuel cell electric vehicles in recent years has led to increased interest in the use of fuel cells as sources of renewable energy. To achieve successful commercialization of fuel cell vehicles, it will be necessary to guarantee the safety, reliability, and lifetime of fuel cell systems by predictive fault detection and isolation (FDI). In this study, the parity equation, an observer, and a Kalman filter are employed together to compare the characteristics of FDI, focusing on the sensors of the thermal management system. Residuals corresponding to the difference between temperature outputs of linear models under driving cycles and nonlinear temperature outputs are used to isolate faults. Then, assessment of three model-based sensor FDI schemes is used to isolate sensor faults using the Cumulative Sum Control Chart (CUSUM) method. Generated residuals are evaluated by CUSUM to detect the presence of a sensor fault. As a result, isolated sensor faults are assessed.

In this paper, we consider a class of first-order hyperbolic distributed parameter systems. Our focus is on the design of a new class of model predictive control schemes using a quasi-Shannon wavelet basis. First, the first-order hyperbolic distributed parameter system is transformed into an equivalent system using collocation techniques for the approximation of spatial derivatives and Euler forward difference method for the approximation of the time component. Then, a model reduction method is applied to obtain a reduced-order system on which a nonlinear model predictive controller is designed through solving a nonlinear quadratic programming problem with input constraints. For illustration, the temperature control of a flow-control long-duct heating system is considered to be an example. A comparative simulation study is conducted to demonstrate the effectiveness of the proposed method.

Low-temperature solid oxide fuel cells permit the possibility of metallic interconnects over conventional ceramic interconnects. Among various metallic interconnects, the ferritic interconnects are the most promising. However, chromium poisoning in them adversely affects their performance. To resolve this issue, various coatings and pretreatment methods have been studied. Herein, this article encloses the coating of CuFe2O4 spinel over two prominent ferritic interconnects (Crofer 22 APU and SUS 430). The CuFe2O4 spinel layer coating has been developed by the dip-coating of both samples in CuFe2O4 slurry, followed by heat treatment at 800 °C in a reducing environment (5% hydrogen and 95% nitrogen). Additionally, both samples were annealed to further enhance their spinel coating structure. The morphological and crystallinity analysis confirmed that the spinel coating formed multiple layers of protection while annealing further reduced the thickness and improved the densities. Moreover, t... [more]

This study describes the technological processes and characteristics of biomass direct combustion power generation, biomass gasification power generation, biomass mixed combustion power generation, and biomass biogas power generation in terms of their importance and application in China. Under the perspective of environmental and economic sustainability, the life cycle assessment (LCA) method and dynamic analysis method based on time value are used to simulate and evaluate the environmental loads and economic benefits of different power generation processes. By comparing with coal-fired power generation systems, the environmental and economic benefits of different biomass power generation technologies are illustrated. The results shows that biomass gasification power generation has the best environmental benefits, with a total load of 1.05 × 10−5, followed by biomass biogas power generation (9.21 × 10−5), biomass direct combustion power generation (1.23 × 10−4), and biomass mixed combu... [more]

Coal mining produces large quantities of discard that is stockpiled in large dumps. This stockpiled material, termed coal discard, poses an environmental threat emphasising the need for appropriate bioremediation. Here, metagenomic analysis of the 16S rRNA from ten coal-degrading strains previously isolated from coal slurry from discard dumps and from the rhizosphere of diesel-contaminated sites was used to establish genetic relatedness to known plant growth-promoting (PGP) bacteria in the NCBI database. Measurement of indole and ammonium production and solubilisation of P and K were used to screen bacteria for PGP characteristics. BLAST analysis revealed ≥ 99% homology of six isolates with reference PGP strains of Bacillus, Escherichia, Citrobacter, Serratia, Exiguobacterium and Microbacterium, while two strains showed 94% and 91% homology with Proteus. The most competent PGP strains were Proteus strain ECCN 20b, Proteus strain ECCN 23b and Serratia strain ECCN 24b isolated from diese... [more]

Paclitaxel (PTX) and anastrozole (ANA) have been frequently applied in breast cancer treatment. PTX is well-known for its anti-proliferative effect meanwhile ANA has just been discovered to act as an estrogen receptor α (ERα) ligand. The combination therapy of PTX and ANA is expected to improve treating efficiency, as ANA would act as a ligand binding with the ERα gene expressed in breast cancer cells and thereafter PTX would inhibit the division and cause death to those cancer cells. In this study, liposome-based nanocarriers (LP) were developed for co-encapsulation of PTX and ANA to improve the efficacy of the combined drugs in an Estrogen receptor-responsive breast cancer study. PTX-ANA co-loaded LP was prepared using thin lipid film hydration method and was characterized for morphology, size, zeta potential, drug encapsulation and in vitro drug release. In addition, cell proliferation (WST assay) and IN Cell Analyzer were used for in vitro cytotoxicity studies on a human breast can... [more]

Anaerobic digestion of poultry manure is a potentially-sustainable means of stabilizing this waste while generating biogas. However, technical, and environmental protection challenges remain, including high concentrations of ammonia, low C/N ratios, limited digestibility of bedding, and questions about transformation of nutrients during digestion. This study evaluated the effect of primary biological treatment of poultry manure on the biogas production process and reduction of ammonia emissions. Biogas yield from organic matter content in the aerobic pretreatment groups was 13.96% higher than that of the control group. Biogas production analysis showed that aerobic pretreatment of poultry manure has a positive effect on biogas composition; methane concentration increases by 6.94−7.97% after pretreatment. In comparison with the control group, NH3 emissions after aerobic pretreatment decreased from 3.37% (aerobic pretreatment without biological additives) to 33.89% (aerobic pretreatment... [more]

A shift towards an economically viable biomass biorefinery concept requires the use of all biomass fractions (cellulose, hemicellulose, and lignin) for the production of high added-value products. As lignin is often underutilized, the establishment of lignin valorization routes is highly important. In-house produced organosolv as well as commercial Kraft lignin were used in this study. The aim of the current work was to make a comparative study of thermoplastic biomaterials from two different types of lignins. Native lignins were alkylate with two different alkyl iodides to produce ether-functionalized lignins. Successful etherification was verified by FT-IR spectroscopy, changes in the molecular weight of lignin, as well as 13C and 1H Nuclear Magnetic Resonance (NMR). The thermal stability of etherified lignin samples was considerably improved with the T2% of organosolv to increase from 143 °C to up to 213 °C and of Kraft lignin from 133 °C to up to 168 °C, and glass transition temper... [more]

To mitigate the power shortage problem in the South Pacific island nations and the equatorial area, we studied the development characteristics of ocean thermal energy conversion (OTEC) using abundant clean ocean energy. Through the simulation of open- and closed-cycle OTEC, the generation amount and its economic efficiency were compared, and the application characteristics of the power generation cycle according to the seawater temperature distribution were compared by applying various seawater temperature conditions. According to the characteristics of seawater heat sources in the region, the power generation output was about 883.2 kW in Samoa, and the average power generation by region was about 650.5 kW for the open-cycle OTEC model. Regional revenue up to approximately $8,487,000 was generated in Kiribati, driven by the higher electricity tariff of $0.327/kWh and high water costs of $5.86/ton. With the spread of 50 MW commercial plants, Kiribati had a high net present value of $1,9... [more]

A common denominator in the vast majority of processes in the food industry is refrigeration. Such systems guarantee the quality and the requisites of the final product at the expense of high amounts of energy. In this regard, the new Industry 4.0 framework provides the required data to develop new data-based methodologies to reduce such energy expenditure concern. Focusing in this issue, this paper proposes a data-driven methodology which improves the efficiency of the refrigeration systems acting on the load side. The solution approaches the problem with a novel load management methodology that considers the estimation of the individual load consumption and the necessary robustness to be applicable in highly variable industrial environments. Thus, the refrigeration system efficiency can be enhanced while maintaining the product in the desired conditions. The experimental results of the methodology demonstrate the ability to reduce the electrical consumption of the compressors by 17%... [more]