Results 31 to 40 of about 1,713,702 (163)
The Genome of Phoebe zhennan (Lauraceae) and Comparative Genomics of Phoebe 楠木(樟科)基因组与楠属植物比较基因组学研究
Phoebe zhennan is a Chinese endemic and valuable timber species of Phoebe (Lauraceae). We present a chromosome‐level genome assembly of P. zhennan. Our research provides novel insights into the genome evolution of Phoebe, including whole‐genome duplication, phylogenetic relationships of magnoliids, and key MYB regulatory genes involved in lignin ...
Mao Yameng +3 more
wiley +1 more source
分别对高温硫化硅橡胶(HTV)和液体硅橡胶(LSR)未老化样品,盐雾老化1 000 h、2 000 h,紫外老化1 000 h、2 000 h试样进行傅里叶变换红外光谱(FTIR)测试,通过特征峰峰值以及特征峰面积的变化来分析不同老化条件对HTV及LSR主链以及侧链的影响,推测其憎水性、机械以及电气性能的变化。实验表明,盐雾以及紫外老化均会引起HTV主链Si-O-Si和侧链Si-CH3、Si-(CH3)2的减少,且增加老化时间会引起化学键持续断裂,这表明盐雾和紫外老化会使HTV憎水性降低 ...
李兴 +5 more
doaj
Our study identifies southern China, including mountainous regions and islands, as key areas rich in phylogenetic diversity, and phylogenetic endemism of lizards that are currently under‐protected. Current protected areas however do not adequately cover regions that are critical for preserving the evolutionary history of lizards.
Tao Liang (梁涛) +8 more
wiley +1 more source
针对氧化锌压敏电阻直流作用下的老化问题。利用氧化锌压敏电阻肖特基势垒理论,对氧化锌压敏电阻在正极性和正、负极性直流交替作用下,氧化锌压敏电阻老化规律进行研究,得出以下结论:1)氧化锌压敏电阻在单一极性直流作用下,产生明显的极性效应。此外,极性效应和老化程度均随电流的增加而增大,当达到最高点时,出现减慢的现象。2)正、负极性电流交替作用时,ZnO压敏电阻出现极性补偿现象,使得肖特基势垒高度下降变慢,导致压敏电阻老化程度较单一极性电流作用下缓慢。
苑吉河 +4 more
doaj
This study investigates the diversity, conservation status, distribution, and discovery rate of 84 Cyrtodactylus species in Indochina. Despite rising discovery rates, many species are unassessed, with over half unprotected and 90.5% endemic. This study suggests expanding protected areas and implementing an integrated approach to conservation with IUCN ...
Matilda Julia Lasota +6 more
wiley +1 more source
Using genomic data from 285 species across 19 planthopper families, we conducted the first phylogenomic study targeting global planthoppers and inferred their phylogeny with the highest resolution so far. We proposed taxonomic changes including the establishment of a new family Borysthenidae stat. rev. and a new superfamily Meenoploidea superfam.
Junchen Deng +9 more
wiley +1 more source
ZnO电阻片冲击电流耐受特性是衡量其稳定性与可靠性的重要因素之一,其冲击老化状态评估判据尤为重要。因此,本研究通过开展ZnO电阻片冲击老化试验,对比分析了ZnO电阻片在冲击老化过程中交/直流伏安特性的相关性和差异性。试验结果表明,采用峰-峰值绘制的交流u-iR特性曲线和正向直流V-I特性曲线两者在阻性电流峰值(直流电流)1mA附近区域较为接近,两者之间的差异在1%左右;且ZnO电阻片直流参考电压U1mA变化约5%时,交流参考电压u1mA变化率约为3%。因此 ...
韩永霞 +6 more
doaj +2 more sources
Chromolaena odorata and Ageratina adenophora are invasive species in Southern Yunnan, China; they have very differing, yet overlapping, climate niches. Both invaders produce a large number of small pappus‐bearing achenes every year. They grow in, and their seeds are dispersed to, both suitable and marginal habitats.
Bin Wen +5 more
wiley +1 more source
本发明涉及检测不溶性硫磺制备过程中老化是否完全的中间产品检验技术,具体地说是一种利用差热分析技术不溶性硫磺制备过程中老化进度检测方法,利用差热分析方法,以空气为检测气氛,检测温度为20℃~200℃,通过测定老化样品差热分析曲线,观测其在30℃~160℃内有无出现明显的放热峰,判断老化是否完全。其实用性好,能快速、准确确定老化程度;在制备不溶性硫磺过程中,本发明使用差热技术,利用老化产品差热峰型变化,适时监空老化进度,达到控制产品质量的目的 ...
徐杰, 孙志强
core
目的:观察改变老化态度对记忆作业的影响,探索其作用途径。方法:直接思维法(正性和负性)改变被试老化态度,联想记忆和图形记忆测量记忆成绩。结果:正性思维条件下被试老化态度较负性思维条件下的分离(积极),正性思维可以提高老年被试的自我效能和记忆作业成绩,负性思维作用相反,其差异均达到显著性;其作用途径与老化态度改变、自我效能情绪状态有关。结论 ...
李川云, 吴振云
core +1 more source

