Microporous Cyclodextrin Film with Funnel-type Channel Polymerized on Electrospun Cellulose Acetate Membrane as Separators for Strong Trapping Polysulfides and Boosting Charging in Lithium-Sulfur Batteries

The“shuttle effect”of polysulfides hampers the commercialization of lithium-sulfur(Li-S)batteries.Here,a thin molecular sieve film was decorated on the surface of an electrospun cellulose acetate(CA)membrane derived from recycled cigarette filters,where the truncated cone structureβ-cyclodextrin(β-CD)was selected as the building block to physically block and chemically trap polysulfides while simultaneously dramatically speeding up ion transport.Furthermore,on theβ-CD free side of the separator facing the cathode,graphite carbon(C)was sputtered as an upper current collector,which barely increases the thickness.These benefits result in an initial discharge performance of 1378.24 mAh g^(−1) and long-term cycling stability of 863.78 mAh g^(−1) after 1000 cycles at 0.2 C for the battery with theβ-CD/CA/C separator,which is more than three times that of the PP separator after 500 cycles.Surprisingly,the funnel-type channel ofβ-CD generates a differential ionic fluid pressure on both sides,speeding up ion transport by up to 69%,and a 65.3%faster charging rate of 9484 mA g^(−1) was achieved.The“funnel effect”of a separator is regarded as a novel and high-efficiency solution for fast charging of Li-S and other lithium secondary batteries.

Preparation and Properties of Light-colored Antistatic ATZO@TiO_(2)/PAN Fiber

Light-colored antistatic polyacrylonitrile(PAN)composite fiber was successfully prepared via a facile wet-spinning process using ATZO@TiO_(2)whiskers as conductive fillers.This kind of low-cost fiber meets the requirements of light-colored and antistatic ability,which is quite suitable for mass production of dust-proof and safety workwear.The conductive whiskers are well dispersed in the fiber and form a continuous conductive pathway,which makes the fiber to possess a long conductive ability.The lowest resistance of antistatic ATZO@TiO_(2)/PAN fiber was 2.1×10^(7)Ω·cm.

Decolorization of reactive dyes by laccase immobilized in alginate/gelatin blent with PEG

To achieve effective decolorization of reactive dyes,laccase immobilization was investigated.Laccase 0.2%(m/V)(Denilite IIS) was trapped in beads of alginate/gelatin blent with polyethylene glycol(PEG),and then the supporters were activated by cross-linking with glutaraldehyde.The results of repeated batch decolorization showed that gelatin and appropriate concentration of glutaraldehyde accelerated the decolorization of Reactive Red B-3BF(RRB);PEG had a positive effect on enzyme stability and led to an inc...

Effects of Treating with Laccase on Properties of Dyed Cotton Fabric

A laccase (Denilite ⅡS) was used to treat different cotton fabrics dyed with 0.2 g·L-1 of vat dyes or reactive dyes. The results indicated that the laccase could remove the loosely adhering, unfixed or hydrolyzed dyes from the dyed fabric efficiently, which led to obvious improvements of color fastness. Furthermore, the wavelength of maximum absorbance of the residual solution of dyeing laccase-treated was different from that of the detergent-treated, which implied the laccase could accelerate structural changes of the adhering or hydrolyzed dyes from fabric in treating, resulting in obvious color changes of the residual solution. In addition, excessive laccase also could decolorize a few fixed reactive dyes from the dyed fabric, with a decrease of color strength and less further improvements of color fastness.

3D Simulation of Two-bar Warp-knitted Structures

In this study,3D computer modeling of simple warp-knitted structures is achieved based on 3D model of warp-knitted loops.Firstly, according to the studying on the geometric structure of warp-knitted loops, Gktepe's 3D solid yarn model is developed,and the dimensions of the warp-knitted loops are obtained;then 3D models of stitch defined by eleven given points and in-lay defined by five given points are built with the method of Non-Uniform Rational B-Spline (NURBS) curves and surfaces.Secondly, according to the chain notations of warp-knitted structures,the loop's shape can be decided, and with the 3D models the loops can be connected freely and smoothly in some special warp-knitted structures,such as miss-lapping and two-course in-lay. At last, with the tools of Visual C++ and OpenGL, computer 3D simulation of two-bar warp-knitted fabrics is successfully realized,taking the factor of fabric light and materials into 3D structural model.

Color Measurement of Segmented Printed Fabric Patterns in Lab Color Space from RGB Digital Images

Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the basic elements in successfully utilizing a color mechanism scheme and objectively evaluating fabric color alterations. Precise color measurement, however, is mostly used in sample analysis and quality inspection which help to produce reproducible or similar product. It is important that for quality inspection, the color of the product should be measured as a necessary requirement of quality control whether the product is to be accepted or not. Presented in this study is an unsupervised segmentation of printed fabrics patterns using mean shift algorithm and color measurements over the segmented regions of printed fabric patterns. The results established a consistent and reliable color measurement of multiple color patterns and appearance with the established range without any interactions.

Fashion Color Forecasting by Applying an Improved Back Propagation Neural Network

Fashion color forecasting is one of the most important factors for fashion marketing and manufacturing. Several models have been applied by previous researchers to conduct fashion color forecasting. However, few convincing forecasting systems have been established. A prediction model for fashion color forecasting was established by applying an improved back propagation neural network (BPNN) model in this paper. Successive six-year fashion color palettes, released by INTERCOLOR, were used as learning information for the neural network to develop a reliable prediction model. Colors in the palettes were quantified by PANTONE color system. Additionally, performance of the established model was compared with other GM(1, 1) models. Results show that the improved BPNN model is suitable to predict future fashion color trend.

Electrospun and woven silk fibroin/poly(lactic-coglycolic acid) nerve guidance conduits for repairing peripheral nerve injury

We have designed a novel nerve guidance conduit（NGC） made from silk fibroin and poly（lactic-co-glycolic acid） through electrospinning and weaving（ESP-NGCs）. Several physical and biological properties of the ESP-NGCs were assessed in order to evaluate their biocompatibility. The physical properties, including thickness, tensile stiffness, infrared spectroscopy, porosity, and water absorption were determined in vitro. To assess the biological properties, Schwann cells were cultured in ESP-NGC extracts and were assessed by morphological observation, the MTT assay, and immunohistochemistry. In addition, ESP-NGCs were subcutaneously implanted in the backs of rabbits to evaluate their biocompatibility in vivo. The results showed that ESP-NGCs have high porosity, strong hydrophilicity, and strong tensile stiffness. Schwann cells cultured in the ESP-NGC extract fluids showed no significant differences compared to control cells in their morphology or viability. Histological evaluation of the ESP-NGCs implanted in vivo indicated a mild inflammatory reaction and high biocompatibility. Together, these data suggest that these novel ESP-NGCs are biocompatible, and may thus provide a reliable scaffold for peripheral nerve repair in clinical application.

Radial Yarn Movement in Yarn Duct of Interlacer

In order to find the relations between the production performance of interlacer and its cross-sectional shapes of yarn duct,radial yarn movement in various yarn ducts of interlacer and its effect on performance of interlaced yarn were studied in this paper.Seven interlacers,which were different in the cross-sectional shape of yarn duct,were made.Yarn motion in yarn duct of interlace was observed with optical fibers and photo-sensors.Performance of the interlaced yarn was evaluated by the number and the strength of tangles.Experimental results disclose the relations between the yarn motions and the properties of the interlaced yarn.The interlacer with round yarn duct is capable of producing an interlaced yarn with bigger number of tangles,since it can make yarn transverse frequently the axis of air jet issuing from air jet nozzle.The interlacer with cornered shape of yarn duct makes yarn subjected to the action of compressed air for a longer time,which results in larger strength of tangles.

Green Modification of Cellulose Nanocrystals and Their Reinforcement in Nanocomposites of Polylactic Acid

Cellulose nanocrystals(CNCs) of rod-like shape were prepared from degreased cotton using sulfuric acid hydrolysis. The obtained CNC suspension was neutralized using a sodium hydroxide solution to remove the residual sulfuric acid and improve the thermal stability of the CNC particles. Then, poly(ethylene oxide)(PEO) was employed to modify the nanocrystals through entanglement and physical adsorption. The goal was to further improve the thermal stability and weaken the hydrophilicity of CNCs. Original and modified CNCs were dosed into a polylactic acid(PLA) matrix to prepare nanocomposites using a hot compression process. Results of the thermogravimetric analysis showed that the initial thermal decomposition temperature of the modified CNCs showed a 120℃ improvement compared to the original CNCs. That is, the thermal stability of the modified CNCs improved because of their shielding and wrapping by a PEO layer on their surface. Results from scanning electron microscopy and ultraviolet-visible spectrophotometry showed that the compatibility of the modified CNCs with organic PLA improved, which was attributed to the compatibility of the PEO chains adsorbed on the surface of the CNCs. Finally, the results of tensile tests indicated a significant improvement in terms of breaking strength and elongation at the break point.

Preparation of Polyimide Fiber/Thermoplastic Resin Composites with Improved Mechanical Properties

As a high-performance material for preparing composite materials, polyimide fibers suffer from many potential drawbacks, including poor bonding with other substrates, which results in composite materials with poor mechanical properties. Therefore, this study proposed a simple and rapid technique for obtaining loose, porous polyimide fiber papers by implementing a wet method using equal amounts of polyimide fiber and polyimide fiber paper as reinforcements, respectively. The polyimide resin-based composite materials were prepared by hand lay-up and hot pressing. The results showed that the paper-based reinforcement exhibited high porosity and the fibers were arranged with a uniform pore size distribution. The tensile properties, bending performance, and interlaminar shear performance of the paper-based composite improved by 130%, 108%, and 34.5%, respectively, compared to those of the fiberbased counterpart. The factors affecting the mechanical properties of the composites were analyzed based on the fiber length, fiber beating or lack thereof, and the basis weight of the paper. The increased uniformity of the polyimide fiber paper changed the ordering of the fibers and resolved drawbacks such as difficult dispersion, uneven pore size distribution, and poor mechanical properties related to single fibers in the resin-based composite material.

Morphology and Properties of Miktoarm Star Styrene-Butadiene Rubber

In order to obtain the optimized structure rubber, a novel miktoarm star styrene-butadiene rubber (MS-SBR) was initiated by a multifunctional macromolecular initiator with polydiene arm and Sn-C bond. The properties of MS-SBR were investigated with respect to the morphology, mechanical properties, and dynamic viscoelasticity in comparison with those of the blends, natural rubber (NR)/star styrene-butadiene random rubber(S-SBR) blend rubber and cis-1,4-polybutadiene rubber (cis-BR)/S-SBR blend rubber. The samples were analyzed using transmission electron microscopy (TEM), dynamic mechanical thermal analyzer (DMTA), and mechanical properties test. The analysis results show that MS-SBR possesses the desired combination of low rolling resistance and high antiskid resistance, and is promising for application in high performance tire tread.

Electro-spinning Antimicrobial N-halamine Modified Poly(vinyl alcohol)Nanofibers

Antimicrobial poly( vinyl alcohol)( PVA) nanofibrous composites were prepared by adding 3-( 2,3-dihydroxypropyl)-5,5-dimethylimidazolidine-2,4-dione( N-halamine diol) to the PVA solution using electro-spinning technique upon curing and exposure to diluted sodium hypochlorite. Scanning electron microscopy( SEM) demonstrates that PVA nanofibers formed with diameters of( 255 ±94) nm. Cross-linked PVA nanofibers with N-halamine diol precursor and 1,2,3,4-butanetetracarboxylic( BTCA) showed good water resistance. The chlorinated PVA nanofibrous mats completely inactivated Staphylococcus aureus( Gram-positive) and Escherichia coli O157: H7( Gram-negative) with 7 log reductions( the reduction of the bacterial concentration in logarithm) within 5min and 1 min of contact time,respectively.

Study on the Preparation of Allyl-modified Starch in Isopropyl/Water Medium for Warp Sizing

A new method for the pretreatment of starch by etherification was developed to eliminate the problems of lower grafting efficiency associated with the preparation of starch graft copolymers as warp sizing agents.The etherification of starch with allyl chloride was investigated in order to effectively enhance the reaction efficiency.The technological variables of the reaction considered for evaluating the etherification included sodium hydroxide amount,water content in water-isopropyl alcohol medium,allyl chloride concentration,reaction temperature and reaction time.The experimental result demonstrated that the variables considered showed evident effect on the reaction efficiency.For the etherification,a condition of 20% for the water content,1.5:1 for the molar ratio of sodium hydroxide to allyl chloride,and at 30℃ under 24 h reaction is sufficient to retain the reaction efficiency above 50%.Furthermore,a contrast test demonstrated that the graft efficiency can be increased with the etherification pretreatment.

Metal-free synthesis of amphiphilic functional polycarbonates

Amphiphilic block copolymers of poly（5-benzyloxy trimethylene carbonate） （PBTMC） and poly（ethylene glycol） （PEG） were synthesized through enzymatic polymerization using immobilized porcine pancreas lipase （IPPL）. The obtained copolymers with different compositions were characterized by GPC and IH NMR. The copolymer composition was in agreement with the feed ratio. The molecular weight of the copolymers showed an increasing trend with the decrease of PEG contents. MiceUes of the copolymers were formed by dialysis procedure, and characterized by transmission electron microscopy （TEM）.

Performance of a Pectinase from Bacillus Subtilis WSHB04-02 Used in Bioscouring of Cotton Fabrics

A pectinase produced by Bacillus subtilis WSHB04-02 isolated from soil with lyase activity operating at alkaline pH was studied. The Michaelis-Menten kinetic parameters of this newly isolated pectinase on different substrates, such as citrus pectin and polygalacturonic acid (PGA), were determined, and pectin proved to be the most suitable substrate. The effects of temperature and pH on pectinase activity and stability were also investigated. The optimal temperature for pectinase was 55℃ with a stable range of 45℃-55℃. In general, pectinase was pH insensitive and the stable pH ranged from 8.6 to 10.0. Ultimately the bioscouring effects of cotton fabrics using this pectinase were evaluated and some promising results were obtained.

Antibacterial Cellulose Coated with N-halamine by Pad-Cure Process

In order to improve the antibacterial property of cellulose,a new N-halamine antibacterial material precursor was synthesized.1,2,3,4-Butanetetracarboxylic acid( BTCA) was used to attach the N-halamine precursor onto cotton fabric as the cross-linking agent. The synthesized compound was characterized by1 H nuclear magnetic resonance(1H NMR). The cotton fabric treated with Nhalamine precursor was characterized by Fourier transform infrared spectroscopy( FT-IR) and scanning electron microscopy( SEM).The antimicrobial efficacy, washing durability and UVA light stability were investigated. The cotton fabric treated with the Nhalamine precursor could be rendered biocidal after exposure to dilute household bleach. The chlorinated cotton fabric shows great antimicrobial efficacy,100% of Staphylococcus aureus( S. aureus)with 1.00 ×10~7 CFU and 99. 998% of Escherichia coli (E. coli)O157∶H7 with 2. 20 × 10~7 CFU can be inactivated with 30 min of contact. Washing durability tests indicate that over 55% of the chlorine can be regained upon rechlorination after 50 washing cycles,and UVA light stability tests show that over 62% of the chlorine can be regenerated after irradiation of 12 h.

Halogen-Free Flame Retarded Poly(Lactic Acid)with an Isosorbide-Derived Polyphosphonate

Fabrication of flame retardants from renewable biomass has aroused extensive interest over the past decade.This work reported a synthesis of isosorbide-derived polyphosphonate(PICPP)as an anti-flammable agent for poly(lactic acid)(PLA).The presence of PICPP notably declined the storage modulus of PLA/PICPP owing to the declined molecular weight of PLA catalyzed by the presence of PICPP.PLA and PLA/PICPP thermally degraded in one stage under either air or nitrogen atmosphere.With increasing the amount of PICPP,the onset thermal decomposition temperature of PLA/PICPP was decreased gradually,owing to the earlier decomposition of PICPP.With only 10 wt%of PICPP,PLA/PICPP-10 achieved a high limiting oxygen index of 30.0%and UL-94 V-0 classification,manifesting that PICPP was an efficient anti-flammable agent for PLA.The inclusion of 15 wt%PICPP also caused 33%and 16%decline in PHRR and THR of PLA,respectively.TG-IR results clarified that PLA/PICPP produced the less typical pyrolysis products especially flammable carbonyls than PLA,which may account for the suppressed PHRR and THR values of PLA/PICPP.

Comparative Study of Polypropylene Non-Woven Surgical Mask and Locally Manufactured Woven and Knitted Fabrics Facial Masks

The outbreak of coronavirus has led to an increase in the demand for facemasks globally. Unavailability of appropriate polypropylene non-woven fabrics face masks as a result of inadequate supply to satisfy the growing population has brought about the manufacturing of locally fabrics masks to augment or substitute standard medical class facemasks. The study aims at analyzing airflow of these locally manufactured fabrics to determine possible means of transmitting the virus as well as establish comfort of the user of these masks. Standard polypropylene non-woven, woven and knitted fabrics were considered for the study. Air permeability test was conducted on these fabrics using Frazier Air permeability tester. Depending on the property significant variation in the textile fabrics, polypropylene non-woven is widely accepted for facial masks. Nevertheless, this study illustrates that woven and knitted fabrics have more open structures, which allow a high rate of air penetration and so may require two or three layers to prevent antimicrobial or antiviral potential.

Liquefaction of Rice Straw with Ethylene Carbonate

In this study,rice straw(RS) was liquefied by ethylene carbonate(EC) using H_2SO_4 as a catalyst.The effects of various process conditions on the liquefaction characteristics were investigated by FT-IR and residue content analysis.The results show that cellulose and lignin are degraded during the liquefaction process and large amounts of groups are generated.In addition,it is difficult to effectively liquefy RS by using EC alone as the liquefying agent without other additives.Compared to water addition on liquefaction,the residue content can be significantly reduced up to 30% by adding H_2O_2.It has also been proved that the liquor ratio(RS/EC,w/v) of 1∶5 with H_2O_2 as an additive at 145℃ for liquefaction time of 60 min in the presence of H_2SO_4 can accelerate the liquefaction process and high liquefaction yield can be obtained.