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Novel polymer‐based materials with highly thermally conductive and high‐mechanical properties have attracted extensive attention in the field of electronic packaging as thermal interface materials (TIMs), due to the development of electronic equipment to miniaturization and higher power density. However, how to achieve high‐thermal conductivity (exceed 5 W/m·K) with low‐filling content (below 30 vol%) is still the focus of attention. Herein, polymer‐based materials with excellent in‐plane thermal conductivity were prepared by a simple hot‐pressing strategy, and a series of nanocomposites with different orientations were controlled by the hot‐pressing times. As expected, compared with that of randomly dispersed 25 vol% BNNS/P(VDF‐HFP) nanocomposite and pristine P(VDF‐HFP), the in‐plane thermal conductivity of oriented 25 vol% BNNS/P(VDF‐HFP) is promoted by 249% and 3057%, respectively. In contrast to randomly dispersed composites, oriented BNNS/P(VDF‐HFP) at loadings above 10 vol% begin to show an encouraging upward trend. This is because the orientation of BNNS can significantly reduce the percolation threshold and construct an efficient heat conduction network under low‐filling volume. Therefore, this technology can provide new ideas for the development of electronic packaging technology. [ABSTRACT FROM AUTHOR]

New types of carbon nanomaterials, such as multiwalled carbon nanotube (MWCNT) and graphene nanoplatelet (GNP), have attracted much attention in enhancing the thermal conductivity of polymers. However, due to the high electric conductivity of carbon materials, it is difficult for carbon‐based epoxy to achieve the high thermal conductivity while obtaining desired dielectric property. In this article, using GNP and MWCNT modified by titanate coupling agent (PN‐105), a novel method for highly thermally conductive, but electrically insulating epoxy nanocomposites is reported. The experimental results show that the 4% modified MWCNTs/epoxy nanocomposite has presented a simple thermal conductivity network, which can significantly improve the thermal conductivity of epoxy resin (EP), about 6.5 times higher than pure epoxy. Co‐filled with 2% GNPs and 4% MWCNTs, the thermal conductivity of the epoxy nanocomposite is increased to 2.04 W/mK, 957% higher than pure epoxy. In addition, the dielectric constant of the composite is 9.1, which is maintained within an acceptable range. The dynamic mechanical results show that the filling of carbon materials can reduce the storage modulus and the loss factor of EP. Preparation process and principle of high thermal conductivity epoxy resin. [ABSTRACT FROM AUTHOR]

Fragment‐dummy‐template molecularly imprinted polymers‐Mn doped ZnS QDs (FMIP−Mn doped ZnS QDs) were synthesized by surface imprinting technique and specifically recognize microcystin (MC), especially MC‐LR, MC‐RR and MC‐YR. Pentylbenzene and L‐arginine were used as fragment dummy template of MC to form specific recognition site cavity. The introduction of dummy template reduced the toxicity and cost of MC as template in the synthesis process. When MC was added to the FMIP, the room temperature phosphorescence (RTP) intensity is quenched regularly, thereby achieving the effect of detecting MC. The two‐fragment‐dummy‐template molecularly imprinted polymers‐Mn doped ZnS QDs (FMIP‐1) have distinct linearly RTP quenching toward MC in the concentration range of 0.0025‐0.0175 nM. The linear relationship between ΔP/P0 and CMC‐LR, CMC‐YR and CMC‐RR were observed with the regression equation ΔP/P0=0.0150+24.70CMC‐LR, ΔP/P0=0.0995+21.38CMC‐YR, and ΔP/P0=0.101+16.96CMC‐RR (where concentration was in nM), with the detection limit of 0.25 pM, 1 pM and 0.6 pM, respectively. This method was applied to detect MC in water and freshwater products. The method have the potential for effective detection of other harmful substances in the complicated matrix. [ABSTRACT FROM AUTHOR]

In this work, a novel naked eye and fluorescence sensor for acetylcholinesterase (AChE) determination based on copper/silver nanoclusters (Cu/Ag NCs) was developed. L‐Histidine protected Cu/Ag NCs were prepared and exhibited superior properties compared with copper nanoclusters, with the quantum yield increased from 4.3% to 13.2%. The fluorescence of Cu/Ag NCs can be easily quenched by 2‐nitro‐5‐thiobenzoate anion (TNB) owing to the inner filter effect. TNB is the product between 5′‐Dithiobis‐(2‐nitrobenzoic acid) (DTNB) and thiols. However, AChE can specially catalyze acetylthiocholine (ATCh) to hydrolyze and release biothiols (TCh). Based on this, the determination of AChE was achieved by introducing DTNB. A naked eye sensor was also constructed owing to the color change. [ABSTRACT FROM AUTHOR]