Bubble-templated Construction of Three-dimensional Ceramic Network for Enhanced Thermal Conductivity of Silicone Rubber Composites

With the continuous development of the electronics industry,the energy density of modern electronic devices increases constantly,thus releasing a lot of heat during operation.Modern electronic devices take higher and higher request to the thermal interface materials.Achieving high thermal conductivity needs to establish an interconnecting thermal conductivity network in the matrix.For this purpose,the suspension of Al203 and curdlan was first foamed to construct a bubble-templated continuous ceramic framework.Owing to the rapid gelation property of curdlan,we can easily remove moisture by hot air drying.Finally,the high thermally conductive composites are prepared by vacuum impregnation of silicone rubber.The result showed that composites prepared by our method have higher thermal conductivity than the samples obtained by traditional method.The thermal conductivity of the prepared composite material reached 1.253 W·m^(-1)·K·^-(1)when the alumina content was 69.6 wt%.This facile method is expected to be applied to the preparation of high-performance thermal interface materials.

Polyethylene glycol phospholipids encapsulated silicon 2,3-naphthalocyanine dihydroxide nanoparticles(SiNcOH-DSPE-PEG(NH2)NPs) for single NIR laser induced cancer combination therapy

Currently,the combination of photothermal therapy（PTT） and photodynamic therapy（PDT） has emerged as a powerful technique for cancer treatment.However,most examples of combined PTT and PDT reported use multi-component nanocomposites under excitation of separate wavelength,resulting in complex treatment process.In this work,a novel theranostic nanoplatform（SiNcOH-DSPE-PEG（NH2）NPs） has been successfully developed by coating silicon 2,3-naphthalocyanine dihydroxide（SiNcOH）with DSPE-PEG and DSPE-PEG-NH2 for photoacoustic（PA） imaging-guided PTT and PDT tumor ablation for the first time.The as-prepared single-agent SiNcOH-DSPE-PEG（NH2） NPs not only have good water solubility and biocompatibility,but also exhibit high photothermal conversion efficiency and singlet oxygen generation capability upon 808 nm NIR laser irradiation.In addition,owing to their high absorption at NIR region,the SiNcOH-DSPE-PEG（NH2） NPs can also be employed as an effective diagnostic nanoagent for photoacoustic（PA） imaging.In vitro and in vivo experimental results clearly indicated that the simultaneously combined PTT and PDT under the guidance of PA imaging with single NIR laser excitation can effectively kill cancer cells or eradicate tumor tissues.Taking facile synthesis and high efficiency in cancer treatment by SiNcOH-DSPE-PEG（NH2） NPs into consideration,our study provides a promising strategy to realize molecular imaging-guided combination therapy.

Mechanism analysis and evaluation of thermal effects on the operating point drift of servo valves

Operating point drift over large temperature spans can significantly degrade the performance of servo valves.The direction and magnitude of the deviation of the operating point are uncertain.To analyze and evaluate the mechanism of this complex system with a multi-level structure and multi-variables,it is necessary to construct a theoretical model with a clear physical concept to describe it.However,since the physical processes contain complex variations of structural parameters and flow properties,there is a problem of simplifying approximations in deriving analytical mathematical relations.The advantages of multi-physics field numerical analysis can compensate for this shortcoming of analytical formulations.Based on this,we constructed a whole-valve transfer function model to realize the mechanism analysis and evaluate the operating point drift when a thermal effect acts on a servo valve.The results show that the asymmetric fit relationship between the armature-nozzle assemblies is an important reason for the drift of the operating point caused by the thermal effect.Differences in structural parameters and fluid medium characteristics at different temperatures lead to nonlinear changes in the operating point.When the deviation angle reaches±1°,an increase in temperature will cause the absolute value of the tangent slope of the displacement deviation of the spool to decrease from 1.44×10^(−5) m/℃to 1.25×10^(−6) m/℃.The influence of the deviation angle is reflected in the change in the absolute value of the tangent slope of the pressure deviation from 1.14×10^(3) Pa/℃to 110 Pa/℃.

The formation of Ca^(2+) gradients at the cleavage furrows during cytokinesis of Zebrafish embryos

In dividing embryos,a localized elevation in intracellular Ca^(2+)([Ca^(2+)]i)at the cleavage furrow has been shown to be essential for cytokinesis.However,the underlying mechanisms for generating and maintaining these[Ca^(2+)]_(i) gradients throughout cytokinesis are not fully understood.In the present study,we analyzed the role of inositol 1,4,5-trisphosphate receptors(IP3Rs)and endoplasmic reticulum(ER)distribution in determining the intracellular Ca^(2+) gradients in early zebrafish blastomeres.Application of the injected Ca^(2+) indicator,Indo-1,showed that during the first cell division a standing Ca^(2+) gradient was formed~35 min after fertilization,with the[Ca^(2+)]_(i) spatially decaying from 500–600 nmol/L at the cleavage furrow to 100–200 nmol/L around the nucleus.While the IP3R immunohistochemical fluorescence was relatively concentrated in the peri-furrow region,ER labeling was relatively enriched in both peri-furrow and peri-nuclear regions.Numeric simulation suggested that a divergence in the spatial distribution of IP3R and the locations of Ca^(2+) uptake within the ER was essential for the formation of a standing Ca^(2+) gradient,and the Ca^(2+) gradient could only be well-established under an optimal stoichiometry of Ca^(2+) uptake and release.Indeed,while inhibition of IP3R Ca^(2+) release blocked the generation of the Ca^(2+)gradient at a lower[Ca^(2+)]_(i) level,both Ca^(2+) release stimulation by inositol 1,4,5-trisphosphate(IP3)injection and ER Ca^(2+) pump inhibition by cyclopiazonic acid also eliminated the Ca^(2+) gradients at higher[Ca^(2+)]_(i) levels.Our results suggest a dynamic relationship between ER-mediated Ca^(2+) release and uptake that underlies the maintenance of the perifurrow Ca^(2+) gradient and is essential for cytokinesis of zebrafish embryos.