Identification of Bamboo Viscose Fibers and Conventional Viscose Fibers

Bamboo viscose fibers and conventional viscose fibers were measured by optical microscopy, scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FTIR), and thermogravimetric analyzer/FTIR spectrometer (TG-FTIR) respectively. At last, the method based on the testing of the Fourier transform near infrared (NIR) spectra was proposed to identify these two kinds of fibers. The discrimination models between bamboo viscose fibers with conventional viscose fibers were built by means of Ward's algorithm and Hierarchical cluster analysis(HCA) after the first derivative and vector normalization pretreatment, and were verified finally. The results indicate that these two kinds of fibers are similar in their morphology both of cross-section and longitudinal direction. What's more, the FTIR spectra, the thermostability, and decomposition products of TG-FTIR experiment are similar, and the testing results contribute little to the effective identification of the two fibers. However, the accuracy of the NIR spectra model is high, and the two kinds of fibers can be classified into two separated groups to achieve the identification simply and exactly.

Nomex／Lenzing Viscose FR混纺纱工艺探讨

对Nomex 462／Lenzing Viscose FR混纺纱的纺纱工艺进行探讨,并对成纱的质量和性能进行测试．结果表明,选择合理的工艺参数后,不同混纺比的N／V混纺纱都具有较好的可纺性,且成纱条干和强伸性能都比较理想．

A Study on the Surface Structures of Viscose-based Activated Carbon Fiber by FT-IR Spectroscopy and XPS

Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at temperatures between 450℃ and 900℃ in N_2 artmosphere. Then, in a successive activation stage, the product carbonized at 600℃ was activated in steam at 450-900℃ for 30 min, and at 600℃ for 5-30 min. The other carbonization products were activated at 600 and 900℃ for 30 min respectively. The products activated at 900℃ were then activated at 450℃ for 30 min again. The starting materiah carbonized products and all activation products were examined by FT-IR spectroscopy and some products were examined by X-ray photoelectron spectroscope (XPS). And the yields of the carbonized and activated products were calculated. By analysing these spectra, the amount of oxygen-containing functional groups of the activated products attained under various activation time, various activation temperature and various previous carbonization temperature was determined.

Radiation Induced Grafting of Acrylic Acid onto Viscose Rayon Fabrics and Its After-Effects

Radiation induced grafting of various polymers with different monomers proved to be an attractive means to modify the physical or chemical properties of polymeric materials or textile fabrics. In the present work, radiation induced grafting of viscose rayon fabrics, consisting mainly of cellulose fibers, with acrylic acid monomer has been carried out. The grafting yields have been thoroughly studied as a function of different applied experimental parameters. The impact of the graft yield on the physical properties of the fabrics such as tensile strength, elongation, swelling, moisture absorption, crease recovery angle and also the dyeing properties of the fabrics has been studied. The effect of increasing the contact time of the fabric and monomer solution, at room temperature, after stopping irradiation has been studied in detail as well as the effect of temperature on the irradiated samples also after stopping irradiation. The best grafting yield was obtained on irradiating viscose rayon fabric in methanol-water solvent containing acrylic acid monomer, at a dose 20 kGys, then heating for 7 hours at 80℃ and finally keeping the samples at room temperature for about 20 hours. That treatment significantly increased the final graft yield.

Radiation Induced Grafting of Viscose Rayon Fabrics with Some Acrylic Acid Derivatives and Styrene

Radiation induced grafting of viscose rayon fabrics, consisting mainly of cellulose fibers, with some acrylic acid derivatives, namely methyl acrylate, acrylamide and acrylonitrile, and also styrene, has been studied. The resultant graft yields have been determined as a function of the applied different experimental parameters. The impact of the graft yields on the physicochemical properties of viscose rayon fabrics such as swelling, moisture absorption, tensile strength, elongation at break, crease recovery angle and also dyeing ability of the grafted fabrics, has been also studied.

CD POLY/Acrylic/Viscose混纺弹性织物气流机染色

用阳离子染料对CD POLY／Acrylic／Viscose混纺弹性织物进行一浴法染色，在大货生产中容易出现色差、折痕和毛头等问题。实验通过分段式升温，控制40-70℃升温速率为1．0℃／min，70-90℃升温速率为0．3℃／min，90-105℃升温速率为0．5℃／min，105℃保温30min能有效控制色差问题；气流机染色选用合适的行机条件也是控制质量问题的关键。设定行机条件为45％的风机，80％N差，机速350m／min，行一圈时间2．75min。大生产证明织物的布面品质良好。

STUDY OF FLAME RETARDING FINISH OF POLYPROPYLENE / VISCOSE BLEND FABRICS

The combustion mechanisms of PP / Viscose blend fabrics are briefly discussed, and the factors affecting flame retarding(FR) effect are analyzed. Apart from this, the choice of processes of FR finish is also discussed in this paper. Other factors such as coating add-on, curing temperature and time are studied too. The results show that the factors above all have different extent of influence upon FR effect.

STUDY ON POLYPYRROLE-VISCOSE CONDUCTING FIBER

The conductivity of Polypyrrole-viscose conducting fiber prepared with author’s method can be shown up to as high as 2.106x10-2 S/cm. The main factors influencing the conductivity are the concentration of FeCl3 used as dopant and initiator, the treatment time of viscose fiber as base material in FeCl3 solution, temperature and polymerization time. It is found that the orientation and crystallization degree of viscose fiber keep constant before and after conducting treatment and the mechanical properties of conducting fiber is the same as that of base material. In addition, the distribution of polypyrrole in viscose fiber, and its effect on the conductivity were investigated in details by TEM.

Preparation and the Pore Structure of Viscose-based Activated Carbon Fibers Treated with Pretreatment Reagents

The viscose rayon was pretreated with four different pre-treatment reagents respectively, and the preparation ofactivated carbon fibers (ACF) was performed undersame carbonizing and activating conditions. The poresize distribution, the specific surface area, and the porestructure parameter of these viscose - based ACF werestudied by using quartz spring balance BET- weightmethod. The experiment result indicates that the poresize distribution and the pore structure parameter ofACF is varied by using different pretreatment reagents.

Comparison between the Direct Dyeing Kinetics of Bamboo and Conventional Viscose Fibers

Two direct dyes were applied to conventional viscose(CV)and bamboo viscose(BV)fibers,which were prepared from bamboo cellulose pulps,and the dyeing kinetics of two fibers were compared.Three kinetic equations,namely Chrastil,Cegarra-Puente,and Vickerstaff,were used to fit the experimental dyeing rate points,showing that the best result was obtained by the Chrastil equation.BV fibers displayed slightly higher dyeing rates and dye adsorption values at initial stages,but a bit lower dye adsorption values at equilibrium than CV fibers.Furthermore,the dyeing of BV fibers exhibited lower activation energies and higher dyeing rate constants than that of CV fibers,and therefore showed slightly lower dependence on temperature.

Effect of Clammy Inula (<i>Inula viscose</i>) Plant Extract in Combination with a Low Dose of the Fungicide Iprodione on <i>Botrytis cinerea in Vitro</i>and <i>in Vivo</i>

The effect of native medical plant “Clammy Inula” (Inula viscosa L.) in combination with a low dose of the fungicide iprodione (Rovral&reg) against gray mould disease (Botryis cinerea Pers.) was evaluated in vitro and in vivo. The results revealed that the plant extract had antifungal effect on mycelial growth rate and conidial germiation of pathogen isolates. The plant extract at the concentration of 1% - 4% and the fungicide iprodione at the concentration of 0.2 - 9 μg&middotml-1 significantly reduced the mycelium growth and germination. In addition, the plant extract at the concentration of 2% - 4% and iprodione at the concentration of 300 - 600 μg&middotml-1 significantly reduced the disease severity (%) on bean plants compared to the controls. The reduction of mycelium growth, germination, and disease severity was positively correlated with increasing plant extract and fungicide concentrations. The combination of a low dose of plant extract and fungicide at (EC50) was able to reduce disease severity of gray mold by 84%. While, plant extract and fungicide alone reduced disease severity by 46% & 39% and by 70% & 76% for the isolate (Bo5-10 and Bc 99), respectively, compared with controls. The application of water extracts of I. viscose in combination of a low dose of an effective fungicide (iprodione) can be a feasible tool in reducing gray mould disease severity, but farther studies are still needed under field conditions to evaluate efficacy against the disease under field conditions.

Property of Polyimide/Flame-Retardant Viscose Blended Fabrics

Although polyimide fibers are excellent intrinsic flame-retardant fibers, their price is so high that they are rarely used in clothing. To expand their application, the polyimide fibers were blended with flame-retardant viscose fibers at a ratio of 30∶70, and the blended yarns were woven with flame-retardant polyester filaments. Fabrics with different parameters, including fabric weaves, warp yarn densities, and fabric layers, were designed, and the effects of those fabric parameters on mechanical properties and flame-retardant properties were tested and analyzed. The results show that the tearing load of the fabrics is affected by fabric weaves, warp yarn densities, and fabric layers, and the tearing load of the weft mountain weave fabric and the twill weave fabric is higher than that of the plain weave fabric. The bursting load of the fabric increases with the increase of warp yarn densities and layers. Among the tested fabric samples, the triple-layer twill fabric has the best flame-retardant performance, which meets the standard of flame-retardant protective fabric Grade B1 level. The research of this paper would provide guidance for the development and production of polyimide blended fabrics.

Research on Thermal Properties of Nomex Fiber and Nomex/Viscose Blended Fabric

Based on the analysis of the properties of Nomex 450 and Nomex 462,the thermal properties of Nomex 462/Lenzing Viscose Flame retardent(FR)blending materials were analyzed.It was discovered through burning test and Thermal Gravity(TG)analysis that the blended material was superior in thermal behaviors to the material made from either Nomex or Viscose FR filament,when the ratio of Nomex and Lenzing Viscose FR reached 80∶20,and excellent thermal properties were achieved with the value of Limiting Oxygen Index(LOI)up to 36.1%.Blending Nomex and Viscose FR filaments may be recommended for better fire retardant property of related fabric.

Effect of Blending Ratio on Properties of Core Yarn and Fabric of Polysulfonamide(PSA)/Flame Retardant Viscose(FRV)/Conductive Filament

In order to develop a fabric with excellent flame resistance function,antistatic function,moisture absorption and breathability,the polysulfonamide(PSA)fiber and the flame retardant viscose(FRV)fiber were blended.Meanwhile,the conductive filaments were used as the core yarn,and then they were made into the core-spun yarn and the fabric at different blending ratios of PSA/FRV.The effects of the blending ratio of PSA/FRV on the mechanical properties and the evenness of the yarn were studied.The effects of the blending ratio of PSA/FRV on mechanical properties,flame retardant properties,antistatic properties,moisture permeability and drape of the fabric were analyzed.With the increase of the blending ratios of PSA/FRV,the strength and the elongation of the core-spun yarn increased firstly and then decreased.Moreover,the evenness of the core-spun yarn was improved,the fabric strength increased firstly and then decreased,the flame resistance decreased,and the antistatic performance improved.These results provide an important basis for the preparation and wide application of fabrics made of PSA/FRV/conductive filament.

Researches on Mechanism of Treatment Technology of Wastewater from Viscose Fibre Production

This paper centres on the mechanism of wastewater treatment technology for viscose fibre production, in-volving the removal of sulphide (S2-), zinc(Zn2+), and organic substances( CODer), and meanwhile, de-termines the optimal strategy for wastewater treatment of Shanghai No. 1 Chemical Fibre Factory. Hydrosul-phuric acid is a weak acid, and in a certain range of pH value(pH 【 8 .18) the concentration of free S2- is below 1 mg/1. The H2S gas can be removed by intro-ducing compressed air. Actually, when pH 【 3, the concentration of sulphide in wastewater can meet the discharge standard. As to zinc (Zn2+), owing to its amphiprotic nature, it can be precipitated completely while pH value is within 8.24-10.5 . With the com-bined method of oxidation and coagulation, the average removal of CODer reaches 81.37% , and the concentra-tion of CODer In the effluent is about 50mg/1 under the best conditions: both the concentrations of oxidant and coagulant are about 60 ppm and the pH is 7 .

Enhanced proton conductivity of viscose-based membranes via ionic modification and dyeing processes for fuel cell applications

Proton exchange membranes(PEMs),which are crucial fuel cell parts,play an important role in the field of energy science.However,the further development of conventional PEMs based on synthetic polymers is greatly limited by high energy consumption and difficult degradation.In this work,we reported the fabrication of a novel viscose-based PEM via cationic modification and dyeing treatment with the reactive dyes KE-7B1.High-efficiency proton transmission channels can be constructed due to the for-mation of the complex internal three-dimensional network of the as-prepared viscose-based PEM.Hþconductivity(sHþ)and water uptake are intensively investigated by changing the cationic agents and KE-7B1,and the maximum sHþreaches 44.19 mS/cm at 80℃and 98%relative humidity(RH).Furthermore,the prepared membrane shows the lowest calculated activation energy value(12.25 kJ/mol),indicating that both Grotthuss and Vehicle mechanisms play an important role in ionic transport.The membrane chemical structure and micromorphology are analyzed and the proton transmission modes are explored in detail,supplemented with research on the hydrophilic/hydrophobic characteristics and crystallinity of the membranes.The application stability of the membranes is also evaluated analyzing the thermal,mechanical,and oxygen resistance properties,and the results show that all the prepared membranes can maintain good thermal stability within 200℃.The maximum tensile strength reaches 42.12 MPa,and the mass losses of the membranes soaked in 30%(in mass,same below)H_(2)O_(2)solution for 120 h can be restricted to 10%.Therefore,as a novel PEM,the obtained dye viscose-based membranes show great potential for application in fuel cells.

Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dynamics in porous materials.The analytical solutions are obtained for the unidirectional and completely developed flow.Based on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is solved.The eigenvalue problem is then solved by the spectral method.Finally,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing parameters.The results show that increasing the Darcy number,the Lewis number,the Dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the flow.Besides,the flow is the most unstable when the channel is vertically oriented.

GLOBAL SOLUTIONS TO 1D COMPRESSIBLE NAVIER-STOKES/ALLEN-CAHN SYSTEM WITH DENSITY-DEPENDENT VISCOSITY AND FREE-BOUNDARY

This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depends on the density in the form ofη(ρ)=ρ^(α).The existence of unique global H^(2m)-solutions(m∈N)to the free boundary problem is proven for when 0<α<1/4.Furthermore,we obtain the global C^(∞)-solutions if the initial data is smooth.

Extreme massive hydraulic fracturing in deep coalbed methane horizontal wells:A case study of the Linxing Block,eastern Ordos Basin,NW China

Deep coal seams show low permeability,low elastic modulus,high Poisson’s ratio,strong plasticity,high fracture initiation pressure,difficulty in fracture extension,and difficulty in proppants addition.We proposed the concept of large-scale stimulation by fracture network,balanced propagation and effective support of fracture network in fracturing design and developed the extreme massive hydraulic fracturing technique for deep coalbed methane(CBM)horizontal wells.This technique involves massive injection with high pumping rate+high-intensity proppant injection+perforation with equal apertures and limited flow+temporary plugging and diverting fractures+slick water with integrated variable viscosity+graded proppants with multiple sizes.The technique was applied in the pioneering test of a multi-stage fracturing horizontal well in deep CBM of Linxing Block,eastern margin of the Ordos Basin.The injection flow rate is 18 m^(3)/min,proppant intensity is 2.1 m^(3)/m,and fracturing fluid intensity is 16.5 m^(3)/m.After fracturing,a complex fracture network was formed,with an average fracture length of 205 m.The stimulated reservoir volume was 1987×10^(4)m^(3),and the peak gas production rate reached 6.0×10^(4)m^(3)/d,which achieved efficient development of deep CBM.

The flame retardancy of alginate/flame retardant viscose fibers investigated by vertical burning test and cone calorimeter

In this research, the flame retardancy of neat alginate fiber, flame retardant viscose fiber （FRV） and alginate/FRV （50/50） blending fibers were investigated by vertical burning and cone calorimeter tests. The vertical burning test showed that the afterflame time of alginate fiber was 0 s, but alginate presented serious smoldering behavior with the afterglow time of 605 s and damaged length of 85 mm, while the afterglow time of FRV was 0 s. When the FRV was incorporated into alginate with the weight ratio of 50/ 50, the afterglow time and damaged length were significantly reduced to 85 s and 35 mm, indicating the smoldering of alginate can be effectively decreased. The morphology and chemical structure of the alginate residual demonstrated that it was seriously destroyed during smoldering process, which was ascribed to its relative low initial thermal degradation temperature. Based on the thermal properties analysis, alginate and FRV fibers shared the concurrence of rapid degradation in the same temperature region of 250-300 ℃, through which, the compact and stable char formed by FRV can prevent the heat transmission and suppress the smoldering of alginate. Further, the cone calorimeter results demonstrated that the time to ignition （TTI） significantly increased and peak heat release rate （PHRR） decreased for alginate/FRV （50/50） compared with FRV. With this research, a new method to overcome the smoldering of alginate was proposed by blending with FRV