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“Rapid response” features enable supercapacitor energy storage systems (SCESSs), used as auxiliary equipment for primary frequency regulation (PFR), to meet the stability and reliability requirements of power grids. In this application, capacity allocation for SCESSs is studied through theoretical derivation and simulation experiments. Firstly, the application scenarios of SCESSs in PFR are analyzed on the basis of weak grid frequency characteristics. Secondly, in two typical operating modes, namely virtual inertia control and droop control, an integrated operating mode is presented with consideration of the start-stop timing and the output depth of SCESSs, and the relationship between the operating modes and rated powers is derived. Then, to satisfy simulation needs of PFR, an analysis model for SCESSs is built, and a common process of SCESS capacity allocation is summarized. Finally, the optimal rated power, virtual inertia coefficient and droop coefficient of an SCESS is calculated with reference events and frequency control requirements of a weak grid as the benchmark. The results show that aforementioned theory is correct and reasonable, and that the proposed method can achieve optimal frequency regulation effects with a small capacity.

The aramid fabrics have been widely used in aerospace, military and protective clothes for light radiation stability properties. The reflection and transmission properties of two kinds of materials (Kevlar 49 fabric and Kevlar 49/Nomex blended fabric) and three weaves of aramid fabrics with different wavelength spectrum were evaluated by ultraviolet-visible-near infrared (UV–Vis–NIR) spectrophotometer analysis. The effects of fabric layers on the reflection and transmission performances of aramid fabric were also discussed. It indicated that the aramid fabrics have good thermal and light protective properties.

In this study, we fabricated fibers with nanoporous structure via needleless electrospinning with a rotating disc from a ternary system of solvent/nonsolvent/poly (caprolactone) (PCL). PCL was dissolved in a mixture solution of dichloromethane (DCM) and N,N-dimethylformamide (DMF) with a certain ratio. During disc-electrospinning, the volatile DCM would evaporate speedily, cooling down the surface of polymer jets, which condensed the water around. After the evaporation of nonsolvent DMF and water, irregular pores were observed both on the surface and the internal part of the fibers.

To improve the quality of needled nonwoven for filtration, many companies will finish the nonwoven fabric in order to improve its performance. The process of singeing with calendering finishing is very important to improve its performance, after finishing the internal filter to a certain extent been blocked, reducing the pressure when cleaning, thereby extending the life of fabrics. We used different methods to deal with needle non-woven fabrics for filtration, which including singeing and singeing with calendering. Then we tested the strength, air permeability, weight and other properties of untreated samples, only singeing samples and singeing with calendering samples. The paper analyzed how treatments affect the properties of needle non-woven fabrics for filtration.

The large amount of waste lye was generated during hydrothermal synthetic zeolite from coal fly ash by microwave-assisted heating. The environment will be polluted, if the improper handing of waste lye, and discharged into the surface water. The washing process of the synthetic zeolite was studied in this paper. Rational recycling of waste lye and reduce the amount of it emissions in the washing process were found. By comparing the environmental effects and the technical and economic, the method of washing with water-acid-water was determined to be the best solution of the zeolite washed. The waste lye can be recovered in this method, and it will be used for preparation of lye in the next synthetic zeolite. Cost was saved, and emissions of waste lye was reduced, too.

In this paper, regenerated silk fibroin/polybutylene terephthalate blended mats were prepared using electrospinning method with different blending ratios. The influence of regenerated silk fibroin/polybutylene terephthalate ratio on the morphology behaviors, fiber diameter and the surface wettability of the blended mats were studied. The morphology of the electrospun fibers were characterized by SEM. The average fiber diameter and its distribution can be obtained from the SEM pictures using software Image J. The average fiber diameter was 280nm to 486nm and it changed with the blending ratio. The contact angles and penetration times were used to characterize the surface wettability of the nanofiber membranes. It was found that with the increase of regenerated silk fibroin amount, the surface contact angles and penetration times decreased, which meant that the wettability was greatly improved.

This paper described a finishing composition and method for applying the composition to three kinds of nonwoven fabrics made from PPS, NOMEX and P84 respectively, which were used in separating the solid particles from flue gas. From the corrosion test and surface energy test, it can be concluded that the filters showed good water repellency and little strength loss after H2SO4 solution treatment, illustrating improved chemical resistance.

Compared microwave-Fenton with Fenton in catalytic oxidation process of Chinese traditional medicine wastewater. The speed of chemical reactions could be improved for more than 10 times by microwave-assisted catalysis. Under microwave irradiation, most of the CODCr removal is concentrated in less than 30s. Radiation power of the microwave affect the removal rate of CODCr, and the best power is related with the water quality.

Oily wastewater from oil field by microwave induced and catalytic demulsification was studied in this paper. The advantages and prospects of the microwave technology was analyzed. Microwave treatment of oilfield wastewater has advantages such as equipment occupies a small space, easy to operate, portable, easy to transport, easy to installation and commissioning, short reaction time, high efficiency, discharge water which has good quality, temperature and other factors do not affect the treatment oilfield wastewater effect and so on. Microwave also has a bactericidal effect which was applicable to treat oilfield wastewater in both South and North of China. When the processing time is 2.5 min at temperature 57°C, microwave demulsification has the best effect. Based on the research of microwave demulsifucation mechanism, a conclusion is reached that microwave heating effect and microwave catalytic eddect play a leading role on the demulsification.

In this paper, the surface finishing process of anti-alcohol, anti-oil and antistatic was applied on terylene needle-punched nonwoven filter material. We used contact angle, anti-alcohol grade, anti-oil grade, static voltage and half-life period as the main indicators for evaluating the effect of the finishing. The organic fluorine TG-410C and nonionic antistatic agent TF-481 were selected as finishing agents. The single factor experiments and orthogonal experiments were carried out on four effect factors of the finishing, including volume percent of organic fluorine, volume percent of antistatic agent, baking temperature, baking duration. The results show an optimum formula: the volume percent of organic fluorine is 20%, the volume percent of antistatic agent is 15%, baking temperature is 170°C, and baking duration is 7min. After finishing, anti-alcohol grade can reach level eight, anti-oil grade can reach level five; the half-life period is less than 1 second. So it can be employed in filtering the air and reducing dust particle and concentration.

Zeolite from coal fly ash is hydrothermal synthesis by microwave-assisted, and it is used to process wastewater. Through the XRD analysis, we discovered that many kinds of zeolites were synthesized in the experiment. The influence factor of zeolite sythesis is chemical composition, activator, temperature, time,etc. This kind of zeolite is used in processing wastewater, removed some positive ions from wastewater, like NH4+,Cu2+,Fe2+,Mn2+,and so on. Meanwhile some PO43+ and CODCr were removed. The main principle of zeolite processing wastewater is cation exchanging. There are physical-chemistry adsorption and the chemical precipitation in this process.

In this paper, two kinds of hydroentangled nonwovens made from the same raw materials and process but different high pressure manifolds is tested to investigate the effect of manifold geometry on the physical performance of products. The results show that the sample treated by slot type manifold has better properties, which has higher hydroentanglement intensity and better abrasion resistance, but no big difference with the pore size distribution. The results are in good agreement with our previous simulation data.

Three novel Brønsted acidic ionic liquids (ILs), 1-(3-sulfopropyl) hexamethyleneiminium hydrogen sulfate ([HMIPS]HSO4), 1-(3-sulfopropyl) hexamethyleneiminium tosilate ([HMIPS]OTs) and 1-hexamethyleneiminium hydrogen sulfate([HMI]HSO4), were synthesized and characterized by1H NMR, FT-IR and DSC-TG. Their catalytic activities for the esterification of citric acid with n-butanol were examined and compared with the imidazolium-based ILs. The results showed that the hexamethyleneiminium-based ILs exhibits excellent catalytic activity. By using [HMIPS]HSO4as the catalyst, the yield of tributyl citrate reached 97.5%. Furthermore, the catalysts were reused at least 10 times without significant decrease in activity