High-efficiency Strategy Research Articles

RETRACTED: A border surveillance system to sense terrorist outbreaks

Wireless Sensor Networks (WSN) are widely used in military applications such as border surveillance. This research focuses on developing a WSN network for implementing in the India-Pakistan border. The traditional approaches used for border surveillance has challenges such as energy efficiency, low cost, latency, information integrity, computation, and communication limitations and needs manual intervention. The conventional method of employing military personnel, fences, and building bulletproof walls and excavation caves at borders are replaced by WSN based sensors, radars, surveillance cameras and Unmanned Ariel Vehicles (UAV) by creating a virtual fence. A hybrid WSN based Border Surveillance System (BSS) architecture using activation scheduling strategy for high energy efficiency, load balancing capabilities, and network lifetime increment is proposed. The proposed integrated BSS architecture reduces manual intervention to a high extent by deploying sensors radars, cameras, and UAVs in place of humans. The results show that the proposed structure and activation methodology are accurate and precise in surveillance and require less maintenance, involve low-cost deployment and provide improved reliability. The experimental analysis shows that the system outperforms the other alternatives in detecting intrusion in boundary fields and has an increased lifetime via effectively handling the network resources.

Ionic liquid-assisted ultrasonic exfoliation of phosphorene nanocomposite with single walled carbon nanohorn as nanozyme sensor for derivative voltammetric smart analysis of 5-hydroxytryptamine

Ultrasonic-assisted liquid-phase exfoliation is one of high-efficiency strategies for preparing two-dimensional (2D) materials. Herein, we report a facile and green synthesis of the phosphorene (BP) obtained from bulk black phosphorus crystal in the ionic liquid (IL) 1-ethyl-3-methylimidazoliumtetrafluoroborate ([EMIm]BF4) through ultrasonic-assisted liquid-phase exfoliation under the continuous nitrogen atmosphere. To gain more insight, the morphology and composition of the as-prepared BP were characterized. The prepared BP showed satisfactory stability in ambient condition containing oxygen and water. In the following, single walled carbon nanohorn (SWCNH) was selected to enhance electrocatalytic capacity and endow oxidase-like (nanozyme) characteristics, which was further applied for electrochemical sensing of 5-hydroxytryptamine (5-HT). Derivative techniques were employed for treating voltammograms to obtain sharper and narrower voltammetric peak, transform asymmetric peak into much more symmetrical peak, reduce background interference, eliminate personal error and directly read the accurate value. Machine learning (ML) model based on artificial neural network (ANN) algorithm as an artificial intelligence approach is adopted to establish smart sensing system via the relationship between concentrations and currents in comparison with traditional linear regression model. The BP-IL-SWCNH nanozyme sensor displayed excellent electrocatalytic ability for second-order derivative voltammetric smart analysis of 5-HT range from 0.3 to 115 µM under optimal conditions.

Liquid-Phase Catalytic Exchange of Hydrogen Isotopes over Platinum on Dual-Modified Graphene.

Although liquid-phase catalytic exchange is an environmentally friendly treatment of hydrogen isotopes in recycled water of a nuclear power station, the successive development of hydrophobic catalysts is still needed to meet much higher catalytic exchange efficiency and stability. Herein, a dual-modified graphene with Pt loading was designed by amination and silanization to anchor Pt nanoparticles uniformly, as well as obtain higher hydrophobicity. After coating the reactor walls with poly(dimethylsiloxane), the catalytic exchange efficiency of the dual-modified graphene with lower Pt loadings (Pt/200-S-NH2-GR) improved up to 91% at 80 °C, which was higher than 80% of only animated graphene (Pt/NH2-GR) at the same condition. Furthermore, the Pt/200-S-NH2-GR maintained high stability for at least 10 h in the temperature range of 40-80 °C, while the Pt/NH2-GR decreased 17% of catalytic exchange efficiency at 80 °C within 10 h. Using the dual-modified strategy for graphene support, high efficiency and stability was achieved for heavy water dedeuteration.

One-pot high efficiency low temperature ultrasonic-assisted strategy for fully bio-based coloristic, anti-pilling, antistatic, bioactive and reinforced cashmere using grape seed proanthocyanidins

The integration of cleaner production technology and bio-based materials is welcomed to achieve a sustainable textile processing. This study introduces a one-step high efficiency and low temperature ultrasonic-assisted strategy for fully bio-based coloristic and functional cashmere using grape seed proanthocyanidins (GSPs) - a considerably generated winemaking by-product. The ultrasonic efficiency and adsorption mechanism under ultrasound were explored through an in-depth statistical analysis using kinetics and isotherms adsorption models. The coloristic, anti-pilling, antistatic, mechanical and bioactive properties of GSPs treated cashmere fabric were investigated. Results revealed that the adsorption of GSPs on cashmere under ultrasound was an endothermic process obeying the pseudo second-order kinetic model. The adsorption efficiency was significantly enhanced via ultrasonic technology by 56% at 60 °C and 101% at 80 °C, which is beneficial to the reduction of processing time and energy consumption. The adsorption of GSPs to cashmere was driven by ionic bond, hydrogen bond and van der Waals force confirmed by virtue of Sips and Langmuir models. These multiple bindings contributes to a good colour fastness, reflected by a marginal colour depth decrease (<10%) after 20 washing cycles. The pilling grade of cashmere after treatment rose above level 4 due to the inhibition of fibres’ entanglement rising from the increased fibre surface smoothness. The half-life periods reduced from 3.2s to lower than 0.5s at 65% relative humidity owing to the improved hydrophilicity of cashmere after treatment. The dramatically enhanced anti-pilling and antistatic performances were well retained against repeated washings. GSPs treated cashmere also displayed enhanced tensile strength, high bacterial reduction rate (95% against Escherichia coli and 92% against Staphylococcus aureus), and strong free radical scavenging capability. In general, the one-step multi-objectives ultrasonic process for fully bio-based textile developed in this research contributes to the sustainable development of textile industry.

A new strategy to realize high energy storage properties and ultrafast discharge speed in Sr0.7Bi0.2TiO3-based relaxor ferroelectric ceramic

Although tremendous studies have been focused on dielectric ceramics to achieve excellent energy storage and charge-discharge performance, the dielectric ceramics with high comprehensive energy storage properties for pulsed power applications are still in shortage. The large hysteresis came from domain switching process, severely weaken the energy storage and charge-discharge properties. Here, a strategy through ergodic relaxors with high dynamic polar nanoregions (PNRs) featuring with fast discharge rate and high energy storage efficiency was proposed to achieve high energy storage properties and extremely fast discharge speed in ferroelectric ceramic. The ergodic relaxors of Sr0.7Bi0.2TiO3 modified by Na0.73Bi0.09NbO3 (SBT-NBN) ceramics were selected to verify the feasibility of the strategy. Encouragingly, large Wrec of 2.49 J/cm3 together with high η of 89.7% can be achieved simultaneously at 250 kV/cm with the composition of 0.96SBT-0.04NBN. The outstanding stability of energy storage characteristics for temperature (25–125 °C) and frequency (1–100 Hz) was also found in 0.96SBT-0.04NBN ceramics. Besides, 0.96SBT-0.04NBN ceramics also possessed an extremely fast discharge rate (~34 ns), remarkable power density PD (57.3 MW/cm3) as well as high current density CD (955.4 A/cm2) at 120 kV/cm. This work provided an original strategy for high energy storage efficiency and high power density ceramics in pulse power applications.

Co-treatment of PVC and used LCD panels in low-temperature subcritical water: Enhanced dechlorination and mechanism

The dechlorination of polyvinyl chloride (PVC) and the removal of organic materials from used liquid crystal display (LCD) are the primary difficulties and steps in the safe disposal of these two types of waste. In this study, the dechlorination of PVC and the removal of organic materials from waste LCD were simultaneously accomplished by using a low-temperature subcritical water (SubCW) co-treatment due to the low dielectric constant and mass transfer resistance of SubCW. The dechlorination efficiency of PVC could be significantly enhanced by introducing waste LCD in the SubCW co-treatment with lower PVC-to-H2O ratio (1:20 g/mL and 1:30 g/mL). The temperature, time, PVC-to-H2O ratio, and PVC-to-LCD ratio have significant influence on the dechlorination efficiency and chlorine distribution. The optimal parameters of the co-treatment were as follows: 220 °C, 90 min, PVC-to-LCD ratio of 4:1, and PVC-to-H2O ratio of 1:30 g/mL. In the optimal conditions, the PVC dechlorination efficiency could reach as high as 100 %. The removed chlorine was completely transferred to the aqueous phase and could be recovered as inorganic chlorine, eliminating the risk of chlorine. It is a remarkable improvement for the PVC dechlorination at low temperature with lower PVC-to-H2O ratio. The organic materials contained in used LCD could be efficiently removed by the SubCW co-treatment above 200 °C, and part of inorganic substances in used LCD could dissolve during the co-treatment due to the interaction between metallic oxides in LCD and HCl removed from PVC. The stable alkene-carbonyl structure (CCO) could be formed in the PVC residue during the SubCW co-treatment of PVC + LCD, promoting the dechlorination reaction of PVC. It is believed that the SubCW co-treatment is a high-efficiency strategy both for the dechlorination of PVC and the pre-treatment of used LCD.

Sustainable Ventilation Strategies for a Medium-Sized Space with Regional Effect

The analysis of ventilation strategies is fundamentally affected by regional climate conditions and local cost databases, in terms of energy consumption, CO2 emission and cost-effective analysis. A systematic approach is covered in this paper to estimate a local economic and environmental impact on a medium-sized space located in two regions during supply-and-installation and operation phases. Three ventilation strategies, including mixing ventilation (MV), displacement ventilation (DV) and stratum ventilation (SV) were applied to medium-sized air-conditioned space with this approach. The trend of the results for three ventilation systems in the life cycle assessment (LCA) and life cycle cost (LCC) analysis is SV &lt; DV &lt; MV. The result of CO2 emission and regional LCC shows that SV is the lowest one in both regional studies. In comparison with the Hong Kong Special Administrative Region (HKSAR) during 20 Service years, the case analysis demonstrates that the percentage differences in LCC analysis of MV, DV &amp; SV in Guangdong are less than 20.5%, 19.4% and 18.82% respectively. Their CO2 emission of MV, DV and SV in Guangdong are more than HKSAR in 10.69%, 11.22% and 12.05%, respectively. The present study could provide information about regional effects in the LCA and LCC analysis of three ventilation strategies emissions, and thereby help set up models for decision-making on high efficiency and cost-effective ventilation strategy plans.

Lighting up solid states using a rubber

It is crucial and desirable to develop green and high-efficient strategies to regulate solid-state structures and their related material properties. However, relative to solution, it is more difficult to break and generate chemical bonds in solid states. In this work, a rubbing-induced photoluminescence on the solid states of ortho-pyridinil phenol family was achieved. This rubbing response relied on an accurately designed topochemical tautomerism, where a negative charge, exactly provided by the triboelectric effect of a rubber, can induce a proton transfer in a double H-bonded dimeric structure. This process instantaneously led to a bright-form tautomer that can be stabilized in the solid-state settings, leading to an up to over 450-fold increase of the fluorescent quantum yield of the materials. The property can be repeatedly used due to the reversibility of the tautomerism, enabling encrypted applications. Moreover, a further modification to the structure can be accomplished to achieve different properties, opening up more possibilities for the design of new-generation smart materials.

An ATP-free in vitro synthetic enzymatic biosystem facilitating one-pot stoichiometric conversion of starch to mannitol.

D-Mannitol (hereinafter as mannitol) is a six-carbon sugar alcohol with diverse applications in food and pharmaceutical industries. To overcome the drawbacks of the chemical hydrogenation method commonly used for mannitol production at present, there is a need to search for novel prospective mannitol production strategies that are of high yield and low cost. In this study, we present a novel approach for the stoichiometric synthesis of mannitol via an in vitrosynthetic enzymatic biosystem using the low-cost starch as substrate. By dividing the overall reaction pathway into three modules which could be executed sequentially in one pot, our design aimed at the stoichiometric conversion of starch-based materials into mannitol in an ATP-independent and cofactor-balanced manner. At optimized conditions, high product yields of around 95-98% were achieved using both 10 g/L and 50 g/L maltodextrin as substrate, indicating the potential of our designed system for industrial applications. This study not only provides a high-efficient strategy for the synthesis of mannitol but also expands the product scope of sugar alcohols by the in vitrosynthetic enzymatic biosystems using low-cost starch-based materials as the input. KEY POINTS : • We described a design-build-test-learn pipeline to construct in vitrobiosystems. • The designed system comprised six key enzymes and another three enzymes. • The system converted maltodextrin stoichiometrically to mannitol in one pot.

High-efficiency synthesis of enhanced-titanium and anatase-free TS-1 zeolite by using a crystallization modifier

A high-efficiency strategy to rapidly synthesize enhanced-titanium TS-1 zeolite without extra-framework anatase TiO2by using 1,3,5-benzenetricarboxylic acid (H3BTC) as a crystallization modifier.

Review of interface solar-driven steam generation systems: High-efficiency strategies, applications and challenges

The interface solar-driven steam generation technology is a new type of solar energy utilization technology that can simultaneously meet the needs of energy, environment, and freshwater. In recent years, this technology has attracted widespread attention and research. With the increasingly advanced high-efficiency strategy, the interface solar-driven steam generation system's performance is rapidly improving. This review discusses this system’s latest developments in various high-efficiency strategies from three perspectives: light absorption, heat utilization, and water and salt control. By analyzing these high-efficiency strategies’ progress and the deficiencies of the systems, it is recommended that future research should pay more attention to (1) the application of comprehensive high-efficiency strategies, (2) unified testing and efficiency calculation specifications, and (3) system stability and cost. Subsequently, this technology's latest applications in seawater desalination, sterilization, sewage treatment, and water and electricity cogeneration are discussed. After the above discussion, the review further analyzes the current systems’ challenges in different practical applications and puts forward suggestions to deal with them.

Poly(p-phenylene benzobisoxazole) nanofiber/reduced graphene oxide composite aerogels toward high-efficiency solar steam generation

Interfacial solar steam generation is emerging as a promising high-efficiency strategy to produce clean water by harvesting and converting clean solar energy to the localized heat. It is highly desirable to introduce robust materials that are able to bear the extreme conditions for advanced applications of solar steam generation. Here, we demonstrate an all-in-one interfacial solar evaporator made from poly(p-phenylene benzobisoxazole) nanofiber (PBONF)/graphene oxide (GO) and PBONF/reduced graphene oxide (RGO) composite aerogels with high porosity, robust mechanical properties, and excellent thermal insulation performance. The evaporators of PBONF/RGO composite aerogel show fast and durable solar-vapor conversion with a high efficiency of 98.4 % under unconcentrated one sun irradiation. The PBONFs not only reinforce the mechanical properties of composite aerogels, but also affords them great potential applications in wastewater purification in some extreme environment, for instance, aerospace.

Distributed Gas Ignition Using Injection Strategy for High Efficiency and Clean Combustion Under Lean Condition

Jet ignition is an efficient way to achieve lean burn of the engine and a promising strategy to meet the stringent emission regulations in the future. This paper presents a distributed gas ignition (DGI) combustion concept and realizes a DGI combustion mode using a newly designed DGI igniter. The igniter integrates a fuel injector and a spark plug to achieve minimum volume and easy installation. As the mixture preparation within the jet chamber is essential for the performance of the igniter, different jet chamber injection strategies were tested with varying excess air–fuel ratio ranging from 1.4 to 2.0. By addressing the dual injection strategy, the ignition delay and combustion duration were improved evidently. Compared with the single injection strategy, dual injection strategy improves the flexibility when preparing the mixture inside the jet chamber and therefore retains more fuel. The increased energy density of the jet chamber helps to generate more energetic jets under dual injection strategy, resulting in the improvement of ignition and combustion performance with lean burn. A higher thermal efficiency and a leaner limit of the engine are attained with dual injection than that with single injection. Dual injection exhibits its potential in reducing CO and THC emissions to an acceptable level with leaner mixture. Based on dual injection strategy, the maximum indicated thermal efficiency of 45% is achieved.

Power distribution strategy based on fuzzy controller and Savitzky-Golay selective filtering in hybrid energy storage system

Lithiumion batteries, as the power of electric vehicles, are facing challenges due to their intrinsic defects. The hybrid energy storage system with the combination of high power supercapacitor and lithium-ion battery are better promising solution. The peak current output by the lithium battery would be reduced greatly, which would result in great heat reduce and further enhancement of life cycle and safety of the lithium-ion battery. In considering their different charge and discharge behaviors, a high efficient control strategy is necessary for better performances. Here, an intelligent energy control strategy that combines fuzzy controller and Savitzky-Golay selective filtering is studied for HESS controlling. The fuzzy controller has good robustness and is suitable for nonlinear control, while the Savitzky-Golay filter can effectively smooth the waveform, and by selecting the output of both can effectively improve cell performance index. The simulation results show that compared with ESS under the tested cycle conditions, the proposed control strategy reduces the maximum current of the battery by 8.5% and the maximum temperature is reduced by 7.98%; when compared with a single fuzzy controller used by HESS, the proposed strategy can reduce the maximum battery current and maximum temperature by 7.02% and 1.50%, respectively.

High efficient strategy for the production of hydroxyapatite/silk sericin nanocomposites

AbstractBACKGROUNDSericin (SS) induces nucleation of bone‐like hydroxyapatite (HAp) when used as an organic matrix. HAp/SS nanocomposites have been conventionally synthesized through precipitation in stirred tank reactors (STs). Despite its simplicity, this process is time consuming and presents difficulties in scale‐up. In our study, HAp/SS nanocomposites were successfully synthesized in a ST and in a meso‐oscillatory flow reactor (meso‐OFR), to compare the efficiency of both reactors and to study HAp mineralization using SS as a template.RESULTSThe production of stable HAp, indicated by pH stabilization, was achieved after 180 min in the ST and after 30 min in the meso‐OFR. X‐ray diffraction and Fourier transform infrared analyses showed that the particles obtained in both reactors are HAp/SS nanocomposites with low crystallinity. Scanning electron microscopy evidenced the formation of rod‐ and plate‐shaped nanoparticles and revealed that the presence of SS led to the production of larger particles. The latter observation was confirmed by laser diffraction. Additionally, increasing SS concentration resulted in the formation of more plate‐like particles.CONCLUSIONSPrecipitation is more efficient in the meso‐OFR, HAp/SS being obtained four times faster. The presence and concentration of SS led to differences in the size and morphology of the synthesized particles, suggesting a critical role of SS in the mineralization process. This work reports a new approach for the manufacture of high‐added‐value nanocomposites with similar characteristics to biological bone and the results of a study of the influence of SS as an organic component in HAp nucleation. Further, the use of this protein and technology leads to significant waste minimization. © 2020 Society of Chemical Industry (SCI)

Multi-dimensional hybrid heterostructure MoS2@C nanocomposite as a highly reversible anode for high-energy lithium-ion capacitors

Lithium-ion capacitors (LICs) are a new generation of hybrid energy storage devices, and there is room for improvement in power characteristic, energy density and cycling life. This paper proposes a facile and high-efficiency strategy for the preparation of high-performance MoS2 based anodes, here we have successfully synthesized a multi-dimensional hybrid heterogeneous composite material (MoS2@C) in which nanoparticles, nanoflakes and hollow nanospheres coexist. The strong adhesion of the Mo-O-C bond formed between MoS2 and carbon ensures favorable structural integrity, while the architecture made of nanoflakes reduces the diffusion distance of Li+. In addition, the voids of the hollow structure can alleviate the volume change during repeated Li+ intercalation/de-intercalation processes and ensure good contact between the material and the electrolyte solution. Moreover, due to the confinement effect of the hollow structure and carbon and the introduction of oxygen vacancies, excellent rate performance is achieved. Given this, in a wide potential window of 0–4.5 V, the MoS2@C//AC device has the highest energy density (189.68 Wh kg−1), the maximum power density (11.25 kW kg−1), subordinate self-discharge rate and long lifespan. Therefore, this research work provides some important ideas and insights for the rational design of MoS2-based high-performance LICs anode materials.

Enhanced Average Thermoelectric Figure of Merit of p-Type Zintl Phase Mg2ZnSb2 via Zn Vacancy Tuning and Hole Doping.

Isoelectronic Zn substitution at the Mg site has been proved to be effective in regulating the carrier concentration of p-type Mg3Sb2 Zintl phase. However, the reported thermoelectric performance is still unsatisfactory compared with that of n-type Mg3Sb2 due to the poor electrical transport properties. Here, we report an enhanced average ZT through improving low-temperature ZTs by introducing Zn vacancy followed suppressing the bipolar effect by doping. First, the Zn vacancy simultaneously increases the power factor and decreases the thermal conductivity, leading to a peak ZT value of ∼0.52 at 773 K in Mg2Zn0.98Sb2. Additionally, doping Li or Ag at the Mg site is identified as a high-efficiency strategy for further increasing the carrier concentration and hence suppressing the bipolar effect. Finally, a peak ZT of ∼0.73 at 773 K and an average ZT of ∼0.46 between 300 and 773 K were obtained in Mg1.98Li0.02Zn0.98Sb2.

Fabrication of anodized superhydrophobic 5083 aluminum alloy surface for marine anti-corrosion and anti-biofouling

Marine corrosion and biofouling seriously affect the service life of marine structural materials, resulting in performance failure, enormous economic loss, and even catastrophic safety accidents. It is worthwhile and desirable to develop high-efficiency strategy for anti-corrosion and anti-biofouling. In this paper, superhydrophobic 5083 aluminum alloy (AA5083) surface with micro-nano hierarchical morphology was fabricated through anodization followed by 1H,1H,2H,2H-perfluorooctyltriethoxysilane (POTS) modification. The surface morphologies, roughness, and chemical compositions were revealed by scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The self-cleaning ability, corrosion resistance and algae adhesion suppression ability of the fabricated surfaces were investigated, indicating an excellent water-proofing, anti-corrosion and anti-biofouling performance. We believe the superhydrophobic creation of metallic materials is expected to have potential applications in marine corrosion and anti-biofouling fields.

Synthetic and antitumor comparison of 9-O-alkylated and carbohydrate-modified berberine derivatives

Berberine is a naturally occurring isoquinoline alkaloid with moderate antitumor effect. It has been proved that berberine can affect the microenvironment of cancer cells, which is critical for cancer therapy and improving human immunity. Therefore, structural modification of berberine to obtain derivatives with high antitumor effect attracts the great attention of scientists. This paper describes the synthesis and in vitro antitumor investigation of some 9-O-alkylated and carbohydrate-modified berberine derivatives using high efficient strategy. The cytotoxicity investigation was accomplished on different cancer cell lines by the well-optimized MTT assay, and the results indicated that 9-O-hydrophobic modified berberine derivative 9 with long lipid chain showed promising in vitro antitumor activity with the IC50 value as low as 4.87 ± 0.24 μM. Percentage of apoptosis was measured by a Hoechst 33342/PI staining strategy on HeLa cells, which revealed that compound 9 could induce 84% of cell apoptosis at very low concentration (5 μM). Flow cytometry analysis indicated that compound 9 might inhibit HeLa cell proliferation by G2 phase arrest. The expression of various cell apoptosis proteins was measured by western blot analysis, and the results indicated that compound 9 could induce over-expression of Caspase-3, Parp, and Bax and down-regulate the expression of P53 and PCNA. All these data indicated the high potential of compound 9 for developing novel anticancer drugs.

Secondary effluent purification towards reclaimed water production through the hybrid post-coagulation and membrane distillation technology: A preliminary test

Shortage of water resource makes the production of high-grade reclaimed water become an important topic. This study proposed the post-coagulation and membrane distillation hybrid technology for further treatment of the secondary effluent to produce the reclaimed water with high quality. The emerging high-efficient polytitanium coagulant was utilized in post-coagulation unit, with the results suggesting its superior coagulation performance than the conventional polyaluminum chloride in terms of both particulates and organic matter removal. The titanium coagulated effluent then flowed to the subsequent direct contact membrane distillation unit for further purification. Permeated flux of the direct contact membrane distillation reached stable value of around 5.1 L/m2·h, which was accompanied by the production of the filtrate with high quality (turbidity < 0.4 NTU and dissolved organic carbon < 1.0 mg/L). Post-coagulation could not only withdraw the foulants from raw secondary effluent, but also improve the subsequent permeate flux and mitigate membrane fouling during membrane distillation process. The foulants attached on membrane surface was the main cause of membrane fouling during membrane distillation procedure. Both economical and practical prospect are included in this study, with the results demonstrated that post-coagulation of the secondary effluent followed by the subsequent membrane distillation procedure was a feasible and high-efficient strategy towards reclaimed water production.