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HIPS-g-MAH compatibilizer and the other three compatibilizers were prepared and added to the polyamide 66/polyphenylene oxide (PA66/PPO) alloy. The FT-IR spectra showed that the maleic anhydride (MAH) had successfully undergone grafting on the high impact polystyrene (HIPS). The effect of the MAH ratio in the HIPS-g-MAH compatibilizer, the HIPS-g-MAH compatibilizer weight ratio, and the PA66/PPO ratio on the mechanical properties of PA66/PPO alloy was systematically studied. The results showed that the PA66/PPO alloy possessed the optimal mechanical properties when the HIPS-g-MAH compatibilizer weight ratio was 7% and the MAH ratio in HIPS-g-MAH compatibilizer ranged 4% ~ 8%. The fracture morphologies of PA66/PPO alloy with different HIPS-g-MAH compatibilizer weight ratios were characterized by scanning electron microscope (SEM). The PA66/PPO alloy without HIPS-g-MAH compatibilizer showed a typical brittle fracture. The mechanical properties of PA66/PPO alloys with the HIPS-g-MAH compatibilizer were improved. In addition, the crystallization temperature of PA66/PPO alloy decreased with the increase in the HIPS-g-MAH compatibilizer weight ratio. The PA66/PPO ratio also played an essential role in the PA66/PPO alloy properties. The coefficient of friction and wear rate both increased with the increase in the PPO ratio.

In this work, polyamide 66/polyphenylene oxide (PA66/PPO) composites, including the flame retardants 98 wt% aluminum diethylphosphinate + 2 wt% polydimethylsiloxane (P@Si), Al(OH)3-coated red phosphorus (RP*), and glass fiber (GF), were systematically studied, respectively. The limiting oxygen index (LOI), UL-94 vertical burning level, and thermal and mechanical properties of the PA66/PPO composites were characterized. The results showed that the P@Si and RP flame retardants both improved the LOI value and UL-94 vertical burning level of the PA66/PPO composites, and PA66/PPO composites passed to the UL-94 V-0 level when the contents of P@Si and RP* flame retardants were 16 wt% and 8 wt%. On the other hand, the mechanical properties of the PA66/PPO composites were reduced from a ductile to a brittle fracture mode. The addition of GF effectively made up for these defects and improved the mechanical properties of the PA66/PPO composites containing the P@Si and RP*, but it did not change the fracture mode. P@Si and RP* flame retardants improved the thermal decomposition of PA66/PPO/GF composites and reduced the maximum mass loss rates, showing that the PA66/PPO/GF composites containing the P@Si and RP* flame retardants could be used in higher-temperature fields.

Halogen-free flame retardants are ideal plastic additives that meet carbon neutral requirements. In this work, halogen free flame retardant with glass fiber reinforced PA66/PPO composites were prepared by using coated red phosphorus (FRM-150B) and phosphorus-silicon flame retardant (WR6002). The mechanical properties, heat resistance, friction and wear properties and flame retardancy were carried out to evaluate the performances of composites using as structural parts that require heat resistance, dimensional stability and accuracy. It was found that the friction coefficient and wear volume of the composites were improved with the contents of glass fiber increased, as a result, PA66/PPO composites was obtained with excellent comprehensive performance when the content of compatilizer is 7%, the glass fiber was 30%, the content of FRM is 8% and the phosphorous-silicon flame retardant is 16%. The flame retardant effect of FRM-150B and WR6002 in PA66/PPO was presented in the condensed phase, the results showed that the composite material with 16% WR6002 forms a carbon layer with excellent thermal stability. On the other hand, the mechanical properties of composites were hardly affected, has important prospects in automotive components and household appliances

On the k-value sensitive effect of K-means algorithm in data clustering, based on the characteristics of density distribution, the kernel density selection scheme is adopted to improve the algorithm. For massive data, the improved algorithm is parallelized based on Flink platform. In the practical application of mobile e-commerce, experiments are repeated in serial mode and parallel mode respectively, and the improved algorithm and K-means algorithm are used for specific comparison. The results show that the improved algorithm will also have good clustering effect in real life. It can be seen that the improved algorithm not only has accuracy and efficiency, but also has practical significance.

With the potential to avoid cross-contamination, eliminate bio-aerosols, and minimize device footprints, microfluidic fluorescence-activated cell sorting (μ-FACS) devices could become the platform for the next generation cell sorter. Here, we report an on-chip flow switching based μ-FACS mechanism with piezoelectric actuation as a fast and robust sorting solution. A microfluidic chip with bifurcate configuration and displacement amplified piezoelectric microvalves has been developed to build the μ-FACS system. Rare fluorescent microparticles of different sizes have been significantly enriched from a purity of ∼0.5% to more than 90%. An enrichment of 150-fold from ∼0.6% to ∼91% has also been confirmed for fluorescently labeled MCF-7 breast cancer cells from Jurkat cells, while viability after sorting was maintained. Taking advantage of its simple structure, low cost, fast response, and reliable flow regulation, the proposed μ-FACS system delivers a new option that can meet the requirements of sorting performance, target selectivity, device lifetime, and cost-effectiveness of implementation.

In this study, NiO/Co3O4 nanocomposites were synthesized by a facile hydrothermal method and exploited as electrode material for electrochemical supercapacitor. The synergistic interaction between NiO and Co3O4 was explored systematically by varying their mass ratio. Interestingly, the electrochemical performances were dependent on the mass ratio of NiO/Co3O4 nanocomposite. NiO/Co3O4 electrode with mass ratio of 1:1 exhibited the highest specific capacitance of 937 F/g at a current density of 1 A/g, due to their distinct microspherical structure with large surface area, which would lead to the more accessible active sites for Faradaic reactions. This investigation provides a useful strategy to develop a new class of electrode materials with the improved electrochemical performance.

A parallel processing method based on the Flink platform is implemented to meet the requirement of big data processing. Simultaneous improvement of the K-Means algorithm is undergone through adopting kernel density options based on the characteristics of density distribution. This is done to decrease sensitivity of the K-Means algorithm to the K value in data clustering. This improved K-means algorithm based on the Flink platform is then applied in the context of E-commerce data. Results show that the improved algorithm based on the Flink platform of parallel computing has better stability as well as efficiency in dealing with these large data sets.

A memristive phenomenon was observed in bulk silver sulfide (Ag2S) nanoparticles assembly, obtained by a chemical reaction method. Current-voltage characteristics of memristors, pinched hysteretic loops were systematically observed in the Ag/ Ag2S /Ag cell. According to the as-obtained stable bipolar IV plots, resistance ratio between high resistance state and low resistance state was measured to be almost 100. An electrochemical redox reaction of S on the interface between Ag electrode and Ag2S electrolyte was proposed to explain the mechanism of the experimental phenomena.

With a theoretical capacity of 1166 mA·h·g–1, lithium sulfide (Li2S) has received much attention as a promising cathode material for high specific energy lithium/sulfur cells. However, the insulating nature of Li2S prevents the achievement of high utilization (or high capacity) and good rate capability. Various efforts have been made to ameliorate this problem by improving the contact between Li2S and electronic conductors. In the literature, however, a relatively high capacity was only obtained with the Li2S content below 50 wt %; therefore, the estimated cell specific energy values are often below 350 W·h·kg–1, which is insufficient to meet the ever-increasing requirements of newly emerging technologies. Here, we report a cost-effective way of preparing nanostructured Li2S-carbon composite cathodes by high-energy dry ball milling of commercially available micrometer-sized Li2S powder together with carbon additives. A simple but effective electrochemical activation process was used to dramatically improv...

A current-controlled memristive one-port was constructed from cobalt monoxide (CoO) using a traditional solid reaction method at 1150 °C in argon atmosphere. Hysteretic current–voltage (I–V) characteristics and resistance switching were investigated in the as-obtained Ag/CoO/Ag cell. Dependences of the I–V loop on voltage range (0 to 10, 11, and 12 V), voltage scan rate (0.1, 1, and 10 V/s), and temperature (323, 373, and 423 K) were reported. A thermistor model for materials with negative temperature coefficient (NTC) was proposed for explanation of the mechanism. An ideal NTC thermistor-based memristive one-port would broaden the applications of memristors and memristive devices.

A kind of aqueous based suspensions of lead lanthanum zirconnate titanate (PLZT) was developed for direct ink writing (DIW) assembly. Piezoelectric ceramic woodpile structures with diameter of 315-470μm were fabricated from these inks by using DIW. The preparation of aqueous based piezoelectric inks, the principle of DIW and the sintering process were systematically discussed. The ink with solids volume fraction over 70% by 1 day aging reveals shear-thinning behavior and proper viscoelastic properties, which ensures a feasible extrusion in the whole shaping process. The PLZT samples sintered at varying temperatures between 1150 oC and 1250 oC for 2h or 4 h in either air or a lead-rich atmosphere yielded various microstructures observed by scanning electron microscopy (SEM). Choosing the optimum sintering condition, the sintered products were densified with relative density exceed 98%. The test of X-ray diffraction (XRD) analysis reveals that the main phase of sintered samples is rhombohedral Pb0.93La0.07(Zr0.65Ti0.35)0.9825O3. The direct ink writing technique has advantages of good design ability and rapid forming capability, which opens up a potential route for the design and fabrication of piezoelectric devices.

Direct-writing is superior in the construction of arbitrarily designed three-dimensional (3D) structures. In this work, we develop a series of organic inks doped with nanoparticles to fabricate 3D meshes of interpenetrating rods. The effects of nanoparticle addition on the rheological properties of organic inks were analyzed. The results revealed intelligible relationship between the ink’s formability and rheological properties, which could be beneficial to the construction of 3D structures from organic inks by direct writing.

A memristive phenomenon was observed in macroscopic bulk negative temperature coefficient nickel monoxide (NiO) ceramic material. Current-voltage characteristics of memristors, pinched hysteretic loops were systematically observed in the Ag/NiO/Ag cell. A thermistor-based model for materials with negative temperature coefficient was proposed to explain the mechanism of the experimental phenomena. Most importantly, the results demonstrate the potential for a realization of memristive systems based on macroscopic bulk materials.

Electric transport properties of sintered polycrystalline Zn0.6Mn0.4Fe2O4 ferrite prepared by traditional solid reaction method were studied. A hysteretic current-voltage characteristic was found, and it could be tuned by both relatively low electric field and magnetic field at room temperature. A magnetic hysteresis related electron transmission model was proposed to explain the results. The tunable electric transport properties are potentially significant for electronic applications, such as nonvolatile random access memories, memristors, and other circuit elements with memory.