The leakage reactance of the compensation transformer in Dynamic Voltage Restorer (DVR) has no corresponding national standards. The paper proposes the LCL filter composed of leakage inductance of ...the transformer and the LC filter at the arm side. According to the design requirements of LCL filter, the transformer leakage inductance and impedance voltage drop are determined, and the parameter selection principles of LCL filter are analyzed combined with the characteristics of DVR. Using the method, the simulations and experimental results of 30 kVA capacity of DVR voltage drop compensation demonstrate that the method can meet the performance indicators, and the harmonic distortion rate of gird voltage after the compensation is less than 5%.
This paper presents a numerical and experimental study of the discharge rate of sawdust from an aerated hopper as an important parameter in many industrial processes involving the handling of other ...granular materials. Numerical experiments are conducted by means of an Eulerian-Eulerian approach coupled with the kinetic theory of granular flow （KTGF）. Emphasis is given to the effects of particle size, hopper outlet width, hopper half angle, aeration height and air flow rate. The results show that the discharge rate is significantly affected by hopper outlet width, particle size and air flow rate, but is not sensitive to the hopper half angle and aeration height： increasing hopper outlet width or air flow rate increases discharge rate, while increasing particle size decreases discharge rate. Close agreement between numerical predictions and experimental results is obtained.
The increasing contamination of water from textile dyes is one of the major environmental problems facing humanity, which has stimulated extensive investigation of fabricating adsorbents with high ...removal efficiency and excellent adsorption capacity towards textile dyes. Nature has engineered some intriguing high-performance materials that may be excellent sustainable materials for water purification use. Herein, we report a novel Juncus effusus (JE)-based adsorbent with a three-dimensional network structure and interconnected channels for dye removal from wastewater. To further enhance its adsorption capacity towards textile dyes, the biodegradable chitosan (CS) was employed for the chemical modification of the JE fiber. The results showed that the CS–JE fibers exhibited a high adsorption capacity towards three types of anionic dyes at the temperature of 296 K: 526.3 mg g−1 for C.I. Acid Yellow 11 (AY11), 452.5 mg g−1 for C.I. Reactive Red 195 (RR195), and 255.1 mg g−1 for C.I. Direct Blue 15 (DB15), which outperforms most of the reported CS-modified adsorbents. The Langmuir model satisfactorily fitted the equilibrium adsorption curves of the CS–JE fibers. Throughout the kinetics studies, the adsorption fitted well with the pseudo-second-order model and exhibited a two-stage of intraparticle diffusion, indicating the adsorption of the investigated dyes onto the CS-JE fiber is rather complex that both the external surface adsorption and intraparticle diffusion occurred simultaneously. Finally, taking advantage of the specific 3D network structure and interconnect channels of the CS-JE fiber, a vertically oriented CS–JE cake was fabricated using CS–JE fibers for continuous filtration of dyes from wastewater. The cake exhibited high flow flux and rapid filtration performance under continuous flow without requiring additional pressure. The present work confirmed that the CS-JE composite can be a promising candidate for wastewater treatment.
Display omitted
•Cleaner Juncus effusus-based adsorbent was fabricated for removal of textile dyes.•Three-dimensional network structure and interconnected channels were observed.•Superior adsorption capacity towards textile dyes was obtained.•Vertically oriented column was fabricated for continuous filtration.•High flow flux and efficient filtration performance were achieved.
This paper discusses a novel research and implementation of dynamic voltage restorer (DVR).The phase diagram is shown based on the principle and the steady-state equivalent circuit. The initial phase ...of the source fundamental voltage and angle are given according to instantaneous reactive power (IRP) theory. The voltage function is determined by the optimum voltage injection angle which is based on minimum energy compensation (MEC). A prototype and the design process are given. The experimental results verify the rationality .
The expression vector pYX212 harboring FLO1 gene and kanMX gene was transformed into Saccharomyces. cerevisiae ZWA46. The transformant, ZWA46-F2, showed strong and stable flocculation ability during ...20 serial batch cultivations. The flocculation onset of the strain is in the early stationary growth phase, not coincident with the glucose depletion in the culture medium. The flocculation ability of the transformant showed no difference with the initial pH ranging from 3.5 to 6.0. Furthermore, the ethanol concentration and other properties of the transformant strain ZWA46-F2 were similar to those of the wild-type strain ZWA46.
Display omitted
•A flexible porous graphene/polypyrrole/Juncus effusus (G-PPy-JE) fibrous electronic was fabricated.•The synergistic effects of the ternary components endow the fiber with abundant ...conductive 3D networks.•The fiber exhibits controllable, stable, and durable Joule heating performance as thermal heaters.•The fiber presents high sensitivity, large working range, and great stability as strain sensors.
Fibrous wearable electronics have attracted extensive attention owing to their lightness and flexibility. However, they face challenges to work synergically with conductive components when stable performance and multifunction are required simultaneously. Here, plant-extracted 3D porous Juncus effusus (JE) fiber decorated with conductive graphene/polypyrrole (G-PPy) yields flexible smart fibers (G-PPy-JE) with integration of Joule heating and strain sensing properties. G-PPy-JE fibers were prepared by hierarchically anchoring the graphene sheets and PPy to 3D JE microfibrils via a facile dip coating and in-situ polymerization method. Synergistic effects in the hybrid architecture contribute to a highest conductivity of G-PPy-JE (96.85 S m−1) compared to pristine JE, G-JE, and PPy-JE. On the one hand, G-PPy-JE fibers showed a great electric-thermal property, which achieved a temperature of 147 °C at 10 V within 10 s. The good Joule heating performance maintained when weaving these fibers into fabrics as thermal therapy clothing. On the other hand, G-PPy-JE fibers after encapsulation can serve as a strain sensor with a high sensitivity (GF of 7.36–11.36), great stability (10–100 %), and good durability over 500 cycles. The strain sensor also reflected capabilities to detect a full range of human motions. This work paves a way for manufacturing cost-effective, green, and versatile fibrous electronics for promising wearable application.
Display omitted
•A natural cellulosic Juncus effusus fiber was used for photodegradation towards dyes.•Three-dimensional network structure and interconnected channels were observed.•99.9 % of ...degradation efficiency was obtained towards different types of dyes.•An orientate fabric was fabricated using the prepared TiO2-JE fibers.
The removal of dyes via photocatalytic degradation has been identified as an eco-friendly method for producing clean and purified water. Natural cellulosic fibers are significant renewable resource and important in a wide range of applications. Herein, we report a natural cellulosic Juncus effusus (JE) fiber with 3D network structure as a framework to provide controllable space for the growth of TiO2 particles. The TiO2-JE showed remarkable activity in the removal of C.I. Reactive Red 120 (RR120), C.I. Direct Yellow 12 (DY12), and methylene blue (MB) with a photodegradation efficiency of 99.9 % under simulated sunlight irradiation. Additionally, an orientate fabric was fabricated using the prepared TiO2-JE fibers for the photocatalytic degradation of dye-contaminated water in the sun, further confirming its practical application. The TiO2 decorated natural cellulosic JE fiber can be a promising material for photocatalysis and sustainable chemistry.
Display omitted
•Antibacterial and antiviral Cu2OPU composite films were fabricated by the improved nonsolvent induced phase separation.•The composites exhibited over 99.99 % inactivation ratio ...against Staphylococcus aureus and H1N1 virus.•The antibacterial activity of the composites remains above 99.99% after cyclic friction, bending, twisting, multi-temperature water dipping, and laundering.
Textile composites are ubiquitous in daily life and are one of the main ways in which bacteria and viruses spread. Highly effective antibacterial and antiviral flexible composites are effective for reducing microbe transmission. Herein, we reported an improved nonsolvent-induced phase separation method for the fabrication of flexible textile composites. Cu2O/polyurethane (Cu2OPU) composite films containing antibacterial and antiviral coatings were constructed using a Cu2O-polyvinyl butyral coagulation bath and binary solvent mixtures, yielding a composite that had excellent mechanical properties and stability and the components did not leach out. The as-prepared Cu2OPU composite films exhibited strong antibacterial and antiviral activity against Staphylococcus aureus and the H1N1 virus (above 99.99 % inactivation ratio). What’s more, Cu2OPU has excellent mechanical and environmental stability owing to the strong interfacial adhesion of Cu2O with the polymer matrix. Furthermore, it can withstand multiple washes and be suitable for daily use. Cu2OPU may be sustainably produced with great scalability, which may meet public, home, and textile applications.
•A heterojunction composite of BiOI/ZnO was successfully synthesized on JE.•BiOI/ZnO composite exhibits a flower-like architecture on the cellulosic JE fiber.•The porous and 3D network structure of ...JE endows the synergistic effect.
Semiconductor heterojunction engineering and three-dimensional (3D) architecture construction have been considered highly desirable strategies to enhance photocatalytic performance. Herein, a BiOI/ZnO composite photocatalyst with a 3D flower-like architecture was successfully prepared, which was stably immobilized on three-dimensional porous lignocellulosic biomass Juncus effusus (JE) fiber. The outstanding photocatalytic performance of the BiOI/ZnO-JE fiber was confirmed by the degradation of tetracycline hydrochloride (TC, 90%), ciprofloxacin (CIP, 79%), and norfloxacin (NOR, 81%). The enhanced photocatalytic activities were mainly attributed to the synergistic absorption performance of the lignocellulosic JE and the effective transfer and separation of charges. Moreover, the hydroxyl (·OH) and superoxide radicals (·O2−) are the main reactive species in the photocatalytic process according to the analysis. This work may provide a novel perspective for constructing high-performance lignocellulosic-based photocatalytic materials.
Display omitted
The ever-increasing complexity of social activities has yielded the call for wearable electronics with combined high performance and multifunction. Although the introduction of three-dimensional (3D) ...structures has proved to be a promising approach, the complicated fabrication process, hazardous precursors, and undesirable performance of 3D structures may pose challenges for developing advanced electronics. Herein, a green and cost-effective carbonized loofah (CL) was fabricated into a versatile flexible electronic for both strain sensing and energy harvesting. The maintained 3D architectures of CL have a promotive effect on improving the responding sensitivity. Therefore, the CL-based strain sensor exhibits advanced characteristics, such as ultrahigh sensitivity (GFmax = 14,639.06), short response time (30 ms), ultralow detection limit (0.01% strain), and good durability (2000 cycles). These features endow the CL with efficient discernibility to monitor multiple complicated human activities (e.g., pulse rate, breathing, phonation). Furthermore, the CL can act as a flexible triboelectric nanogenerator (TENG) for energy collection, providing a potential sustainable energy supply for the continuous working of the sensing system. Therefore, the biomass-derived CL with instinct structures may be a promising platform for the fabrication of multifunctional wearable devices for human health monitoring and portable power sources.
Display omitted
•A multifunctional wearable electronic was fabricated firstly using carbonized loofah (CL).•CL strain sensor performs ultrahigh sensitivity, fast response, and ultralow detection limit.•It can precisely detect both tiny and large movements inducted by human activities.•Cracks propagation of 3D architectures of CL contributes to its high sensing ability.•CL also acts as triboelectric nanogenerator (TENG) for energy harvesting and self-powered strain sensing.
