Bimodal Sintered Silver Nanoparticle Paste with Ultrahigh Thermal Conductivity and Shear Strength for High Temperature Thermal Interface Material Applications

A bimodal silver nanoparticle (AgNP) paste has been synthesized via the simple ultrasonic mixing of two types of unimodal AgNPs (10 and 50 nm in diameter). By sintering this paste at 250 °C for 30 min, we obtained an ultrahigh thermal conductivity of 278.5 W m^–1 K^–1, approximately 65% of the theoretical value for bulk Ag. The shear strength before and after thermal cycling at 50–200 °C for 1000 cycles was approximately 41.80 and 28.75 MPa, respectively. The results show that this excellent performance is attributable to the unique sintered structures inside the bimodal AgNP paste, including its low but stable porosity and the high density coherent twins. In addition, we systematically discuss the sintering behavior of this paste, including the decomposition of the organic layers and the formation of the coherent twins. On the basis of these results, we confirm that our bimodal AgNP paste has excellent potential as a thermal interface material for high temperature power device applications

Performance of bioelectrochemical systems inoculated with <i>Desmodesmus</i> sp. A8 under different light sources

<p>Light source can affect the stomata opening, photosynthesis process, and pigment content in microalgae cells. In this study, growth rate, chlorophyll <i>a</i> (chl <i>a</i>) content, and electrogenic capability of <i>Desmodesmus</i> sp. A8 were investigated under incandescent and fluorescent lamps. Growth rate, productivity, and chl <i>a</i> content of strain A8 exposed to incandescent light were recorded as 0.092 ± 0.010 day⁻¹, 0.019 ± 0.008 g L⁻¹ day⁻¹, and 15.10 ± 1.40 mg L⁻¹, which decreased to 0.086 ± 0.006 day⁻¹, 0.012 ± 0.004 g L⁻¹ day⁻¹, and 10.06 ± 1.59 mg L⁻¹, respectively, under fluorescent light. The stable current density of bioelectrochemical systems inculcated with strain A8 under incandescent and fluorescent lamps were 249.76 and 158.41 mA m⁻² at −0.4 V vs. Ag/AgCl, coupling with dissolved oxygen within biofilm decreasing from 15.91 to 10.80 mg L⁻¹. This work demonstrated that illuminating microalgae under an incandescent lamp can improve biomass production and electrogenic capabilities.</p

Photomicrographs of gallbladder samples stained with hematoxylin and eosin in each group.

<p>The magnification of photomicrographs is ×400. (a) Cholecystic pathology of a representative sample from the group that underwent the sham operation, showing normal gallbladder histology. (b) Cholecystic pathology of a representative sample of an animal from the CBDL-1 group, indicating edema, congestion, and a few inflammatory cells infiltrating into the mucosa. (c) Cholecystic pathology of a representative sample of an animal from the CBDL-2 group, indicating pathological changes of gallbladder resembling that of the CBDL-1 group. (d) Cholecystic pathology of a representative sample of an animal from the CBDL-3 group, exhibiting pronounced edema with significant inflammatory cell infiltrates in the lamina propria.</p

The expression of CBS in guinea pig gallbladder.

<p>Representative images of gallbladder sections stained for CBS are shown (×400). (a) Sham group, positive staining detected in the mucosal epithelial cells. (b) CBDL-1 group, positive staining detected in the mucosal epithelial cells. (c) CBDL-2 group, positive staining observed in the mucosal epithelial cells. (d) CBDL-3 group, positive staining detected in gallbladder epithelia, muscular layer, and blood vessels.</p

CBS and CSE protein expression in guinea pig gallbladder.

<p>CBS and CSE expression was assessed by western blot analysis, with GAPDH as the internal loading control. The bands detected by western blotting were subjected to semi-quantitative densitometric analysis and expressed as the relative CBS and CSE expression levels, after normalization to GAPDH levels. Data shown are the mean ± SD (n=12/group). *<i>P</i> <0.05 vs. sham; #P <0.05 vs. CBDL-1 and CBDL-2. </p

The expression of CSE in guinea pig gallbladder.

<p>Representative images of gallbladder sections stained for CSE are shown (×400). (a) Sham group, positive staining detected in the mucosal epithelial cells and serosal layer. (b) CBDL-1 group, positive staining detected in gallbladder epithelia, blood vessels, and serosal layer. (c) CBDL-2 group, positive staining detected in gallbladder epithelia, blood vessels, and serosal layer. (d) CBDL-3 group, positive staining found in gallbladder epithelia, muscular layer, and blood vessels. </p

H₂S synthesis in the gallbladder from guinea pigs.

<p>Data shown are the mean ± SD (n=12/group). * <i>P</i> <0.01 vs. sham; #P <0.01 vs. CBDL-1 and CBDL-2. </p

Effect of Common Bile Duct Ligation (CBDL) on Gallbladder Inflammation Scores.

<p>Data shown are as the mean ± SD (n=12/group). *<i>P</i> <0.05 vs. sham; #P <0.05 vs. CBDL-1 and CBDL-2.</p

Orthologous segments between date palm (<i>Phoenix dactylifera</i>) and seven other plant species.

a<p>MicroRNA located in the contig;</p>b<p>Arabidopsis thaliana (ath), Citrus sinensis (csi), Glycine max (gma), Oryza sativa (osa), Solanum lycopersicum (sly), Populus trichocarpa (ptc), and Malus domestica (mdm).</p>c<p>Numbers in brackets represent numbers of conserved genes in orthologous blocks.</p

Genome-wide identification of WRKY genes and their expression profiles under different abiotic stresses in <i>Elaeis guineensis</i>

<div><p>African oil palm (<i>Elaeis guineensis</i>) is an important oil crop grown in tropical region and sensitive to low temperature along with high tolerance to salt and drought stresses. Since the <i>WRKY</i> transcription factor family plays central roles in the regulation of plant stress tolerance, 95 genes belonging to the <i>WRKY</i> family were identified and characterized in oil palm genome. Gene structure analysis showed that <i>EgWRKY</i> genes have considerable variation in intron number (0 to 12) and gene length (477bp to 89,167 bp). Duplicated genes identification indicated 32 <i>EgWRKY</i> genes originated from segmental duplication and two from tandem duplication. Based on transcriptome data, most <i>EgWRKY</i> genes showed tissue-specific expression patterns and their expression could be induced under cold stress. Furthermore, six <i>EgWRKY</i> genes with more than two-folded increased expression level under cold stress were validated by RT-qPCR, which has higher expression level in cold, drought and high salinity treatment. The identification and characterization of WRKY gene family showed that <i>EgWRKY</i> were associated with a wide range of abiotic stress responses in <i>Elaeis guineensis</i> and some <i>EgWRKY</i> members with high expression levels could be selected for further research in analyzing their functions in the stress response in African oil palm.</p></div