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Silver nanowire (AgNW) has excellent thermal conductivity, which is an ideal material for fabricating flexible electrical heating materials. However, the poor stability of AgNWs is far from meeting the requirements for the practical application of electrical heating materials. Herein, by imitating the layered structure of nacre, the reduced graphene oxide (rGO)/AgNWs paper with a nacre-like structure was successfully prepared using a simple gravity-induced deposition approach. The obtained rGO/AgNWs paper showed excellent electrical conductivity (19.61 Ω/sq) and good pattern adjustability at the rGO to AgNWs ratio of 1:1. More importantly, the rGO/AgNWs paper exhibited high resistance to oxygen and water vapor, thus realizing long-term stability and reliability. Moreover, the design of a nacre-like structure could improve the thermal management performances of rGO/AgNWs paper, making it achieve a high Joule heating temperature (∼215.83°C) at low supplied voltages (3 V), the rapid response time (∼12 s) and long-term heating stability. These results indicate that the prepared rGO/AgNWs paper promises to be an electrical heating component with high chemical stability for thermal management electric materials.

A hybrid pharmacophore approach was adopted to design and synthesize new series of pyridone-thiazole hybrid compounds. The structures of the compounds were established by IR, 1H NMR, 13C NMR, and HRMS. All the newly prepared compounds (3a-3m) were in vitro evaluated for their antiproliferative activity against three human cancer cell lines, namely Colon cancer (HCT-116), gastric carcinoma (MGC803) and hepatocellular cancer (Huh7). Bioassay results demonstrated that most of the tested compounds showed potent anti-tumor activities against various cancer cells in vitro, and some compounds exhibited stronger effects than positive control 5-Fluorouracil (5-FU). Compound 3b showed the best anti-tumor activity with IC50 values of 8.17 μM and 3.15 μM against HCT116 and MGC803 cell lines, respectively, which was 1.4–8.1 times more potent than 5-Fluorouracil (IC50 = 11.29 μM and 25.54 μM against HCT116 and MGC803 respectively). These findings suggest that compound 3b may have potential to be developed as a promising lead for the design of novel anticancer small-molecule drugs.

A simple and novel synthesis of spirocyclic oxindole derivatives by the reaction of ( E)-3-arylideneindole-2-ones and 1,4-dithiane-2,5-diol via a Michael-aldol cascade under solvent-free reaction conditions is reported. This method provides a new practical and facile approach to 4′-hydroxy-2′-aryl-4’,5′-dihydro-2' H-spiro[oxindole-3,3′-thiophen]-2-ones in moderate to good yields. The structures of all the products were characterised by NMR, infrared spectroscopy and HRMS.

Sn-substituted mesoporous SiO2 (Sn-SiO2) was prepared by hydrothermal crystallization and characterized with XRD, N2 adsorption and TEM techniques. The results showed that the prepared materials exhibited an ordered mesostructures and high surface areas. The effect of poplar treated with Sn-SiO2 and APP on the combustion and smoke was studied by CONE calorimeter. The results show that the heat release rate (HRR), the total heat release (THR), the smoke production rate (SPR) and the total smoke production (TSP) decreased remarkably while the char- ring drastically increases, indicating that the compound of Sn-SiO2 and APP have excellent inflame-retarding and smoke inhibition effects for poplar. It is because APP, as catalyst, leads to the formation of carbon and the silica en- hances the thermal stability of carbon at a high-temperature. Meanwhile, the Sn-SiO2 shows high catalytic activity for smoke and toxic gas produced by wood combust, which can reduce the concentration of CO effectively and avoid fur- ther casualties.

Collapse-type shrinkage is one of highly refractory drying defects in low-medium density plantation-grown eucalypt wood used as solid wood products. Basic density (BD), microfibril angle (MFA), double fibre cell wall thickness (DWT), proportion of ray parenchyma (RP), unit cell wall shrinkage, total shrinkage and residual collapse, which are associated with collapse-type shrinkage characteristics, were investigated by using simple regression method for three species of collapse-susceptibleEucalyptus urophyll,, E. grandis andE. urophylla×E.grandis, planted at Dong-Men Forest Farm in Guangxi autonomous region, China. The results indicated that: unit cell wall shrinkage had a extremely strong positive correlation with BD, moderately strong positive correlation with DWT, and a weakly or moderately negative correlation with RP and MFA; total shrinkage was positively correlated with BD, DWT and RP and negatively related to MFA, but not able to be predicted ideally by any examined factors alone owing to lower R2 value (R2≦0.5712); residual collapse was negatively correlated with BD and DWT, linearly positively correlated with MFA, and had strongly positive linear correlation with RP. It is concluded that BD can be used as single factor (R2≥0.9412) to predicate unit cell wall shrinkage and RP is the relatively sound indicator for predicting residual collapse

In order to explore the production process, fire retardant properties and mechanical properties of retardant poplar plywood, this paper, with poplar veneer as testing material, centers on the manufacture of flame-retardant plywood by the use of ammonium polyphosphate flame retardant. The optimized impregnation process of veneer was explored by oxygen index method and photometry. The fire retardant properties of plywood were studied by cone calorimeter method. It was showed that: the optimized of veneer impregnated process was taking soaking temperature of 40 °C, soaking time of 0.5 h and impregnated concentration of 20%. APP flame-retardant could significantly shorten the combustion duration time of poplar plywood and greatly reduce the heat release rate, total smoke release as well as the mass loss rate, and thus obviously enhance the mass of combustion char residue, which reflected the fact that the APP flame retardant had a significant retardant effect. But the total increasing smoke emission also indicated that smoke-suppression property of APP flame retardant still needed to be improved. Through a comprehensive analysis on APP, we could see that it was a better flame retardant.

With bagasses as testing material, UF as adhesive and APP of liquid and powder as flame retardants, amount of flame retardants content, glue consumption and design density as testing factors, orthogonal experiment was conducted. Retardant and mechanical properties were tested by cone calorimeter and universal mechanical testing machine, respectively. The results showed that: with the increasing of APP adding content, curing time of UF reduced, viscosity of UF decreased and bonding strength reduced. The optimal parameters were: process of bagasse board was processed by liquid APP, the adding mount of APP was 12%, the amount of UF was 15%, density designed of board was 0.85g/cm3.

In this paper, a patch antenna with an PBG (photonic band-gap) structure was studied by FEM method, and the theory of PBG structure was introduced. The Ansoft HFSS is used for the simulation. A comparison between the conventional patch antenna and the new PBG antenna is given. It is shown that the surface waves propagating along the substrate surface can be suppressed by the periodic structure due to the influence of its forbidden band. As a result, the patch antenna based on the PBG structure has a higher gain and a wider bandwidth in comparison with the conventional patch antenna.

The chemical components from benzene/ethanol extractives of fresh Chinese-fir wood were separated and identified by GC/MS after enriched. Relative content of each component was determined by area normalization. 18 compounds representing 94.96% of the extractives were identified. The main and abundant constituents were octadecanoic acid, methyl ester(16.95%), nonadecanoic acid, methyl ester (cas) (15.23%), hexadecanoic acid, methyl ester (cas) (7.12%), hexadecanoic acid, ethyl ester (cas) (6.83%), dibutyl phthalate(6.09%), cholest-5-en-3-ol (3a)- ,carbonochloridate(5.45%), isopropyl myristate(4.52%), hexadecane (cas) (4.31%), benzene (cas) (4.09%), 3,7,11,15- tetramethyl- 2-hexadecen-l-ol(4.01%), tetradecanal (cas) (3.62%), 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl) ester (cas) (3.57%), a-cedrene (3.30%), nonadecane(3.14%), 1- tridecanol (2.96%), 1,2-benzenedicarboxylic acid, bis(2- methylpropyl) ester (cas) (2.21%), and so on. The most components of benzene/ethanol extractives of fresh Chinese-fir wood are not only abundant and healthy to human, but also used as bioenergy.

Now water, adhesives and other assistants are severely wasted because the extractive of Eucalyptus wood is enriched. What's worst, water pollution becomes more serious because of the polluting extractives of Eucalyptus wood. Therefore, based on the single-factor method, the fresh E. camaldulensis shavings were treated in the sorbitic extractor and supersonic wave extractor. The extractives were analyzed by ZETA and SIZER to find out the leaching rule of nano particles from E. camaldulensis wood, hence to obtain the way to lower the negative effect of the extractives. The results were following as: (1) the regression curve showed that the extraction mass increases when the extracting time extends in the sorbitic extractor; (2) diameters of leached nano particles distribute from 37.8 to 106 nm by volume evaluating indicator, and 28.2 to 91.3 nm by number evaluating indicator in the sorbitic extractor. The particles with diameters of 4150~5560 nm, 1110~6440 nm and 4150~5560 nm are too few to test, and their volume are only 0.3%, 2.6% and 0.3% respectively, however, they can bring barrier of wood extractives on wood permeability and obstructive action of wood turpentine on pulping; (3) the volume of the particles with diameter of 28.2~78.8 nm was 80.1%, the number of the particles with diameter of 24.4~50.7 nm was 89.0%, and the volume of 190~396 nm particles is 15.2%, but its number was very less. Therefore, not only extraction mass is increased but also the grouping number of leached nano particles from E. camaldulensis is lowered in supersonic wave extractor.

A novel class-AB implementation of a current-mode programmable gain amplifier (CPGA) including a current-mode DC offset cancellation loop is presented. The proposed CPGA is based on a current amplifier and provides a current gain in a range of 40 dB with a 1 dB step. The CPGA is characterized by a wide range of current gain variation, a lower power dissipation, and a small chip size. The proposed circuit is fabricated using a 0.18 μm CMOS technology. The CPGA draws a current of less than 2.52 mA from a 1.8 V supply while occupying an active area of 0.099 μm2. The measured results show an overall gain variation from 10 to 50 dB with a gain error of less than 0.40 dB. The OP1dB varies from 11.80 to 13.71 dBm, and the 3 dB bandwidth varies from 22.2 to 34.7 MHz over the whole gain range.

This paper focuses on a new design of a down-conversion mixer for a low-IF wideband receiver. Based on the folded structure and differential multiple gated transistor (DMGTR) technique, a novel quadrature mixer with a high conversion gain, a moderate linearity, and a moderate NF is proposed. The mixer is designed and implemented in a 0.18-μm CMOS process, and can operate in a frequency range from 150 kHz to 1.5 GHz. The circuit performance is confirmed by both simulation and measurement results. The measurement results exhibit a peak conversion gain of 13.35 dB, a high third order input referred intercept point of 14.85 dBm, and a moderate single side band noise figure of 10.67 dB. Moreover, the whole quadrature mixer core occupies a compact die area of 0.122 mm2. It consumes a current of 3.96 mA (excluding the output buffers) under a single supply voltage of 1.8 V.