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991.
在“十四五”开局起步的春天,全国电影工作会在北京胜利闭幕。打造献礼建党百年电影精品,扎实推动电影高质量发展是本次会议主题,也是晓晖部长讲话的核心思想。全国电影工作会是在建党100周年的岁首和“两个一百年”历史交汇的关键时期召开的重要会议,王晓晖部长发表的重要讲话,具有特殊重要的意义,恰逢其时,意义深远。  相似文献   
992.
赵玮 《今日消防》2021,6(12):121-123
近年来,科技发展持续发展,人们的生活愈加富足.城市化进程不断加快,各种市场主体层出不穷,对消防监测培训工作提出更高的要求.在如今多媒体信息智能时代,如何逐步改进防火监测工作,通过先进信息手段提高防火监测工作的实效和成果,是防火部门始终摸索和研讨的问题.文章主要研究了当前防火监测管理任务中存在的弊端,深入研究了信息时代防火监测工作的改进举措,并为现代防火监测培训工作提出一些建议.  相似文献   
993.
Hydrogen evolution from ammonia borane (AB) hydrolysis is of great importance considering the ever-increasing demand for green and sustainable energy. However, the development of a facile and efficient strategy to construct high-performance catalysts remains a grand challenge. Herein, we report an amino-group and space-confinement assisted strategy to fabricate Rh nanoparticles (NPs) using amino-functionalized metal-organic-frameworks (UiO-66-NH2) as a NP matrix (Rh/UiO-66-NH2). Owing to the coordination effect of amino-group and space-confinement of UiO-66-NH2, small and well-distributed Rh NPs with a diameter of 3.38 nm are successfully achieved, which can be served as efficient catalysts for AB hydrolysis at room temperature. The maximum turnover frequency of 876.7 min?1 is obtained by using the Rh/UiO-66-NH2 with an optimal Rh loading of 4.38 wt% and AB concentration of 0.2 M at 25 °C, outperforming most of the previously developed Rh-based catalysts. The catalyst is also stable in repetitive cycles for five times. The high performance of this catalyst must be ascribed to the structural properties of UiO-66-NH2, which enable the formation of small and well-dispersed Rh NPs with abundant accessible active sites. This study provides a simple and efficient method to significantly enhance the catalytic performance of Rh for AB hydrolysis.  相似文献   
994.
Eight lactic acid bacteria (LAB) strains were screened for their ability to inhibit Fusarium graminearum (F. graminearum) growth and remove deoxynivalenol (DON). Furthermore, the selected LAB strains were applied as starter cultures to evaluate their performance during the breadmaking process. Lactobacillus plantarum (L. plantarum) AR524 exhibited strong inhibitory activity against F. graminearum growth in a pH-dependent manner and removed up to 40.9% of DON, mainly through cell wall binding. Compared with the control, L. plantarum AR524 inhibited 60.19% of F. graminearum growth and removed 50.53% of DON during breadmaking. The texture properties of the bread were also remarkably improved by L. plantarum AR524, and its shelf life was extended from 3 days to 6 days without the application of any chemical preservatives. Therefore, L. plantarum AR524 shows excellent potential for application as a bioprotective starter culture in bakery products.  相似文献   
995.
The present study aims to examine fruit cell wall-associated fruit softening in Lycium barbarum L. by the microstructure of the fruit cells and the changes in the contents of cell wall components, molecular weights of cell wall polysaccharides and the activities of related cell wall degrading enzymes at different development stages of L. barbarum L. fruit. Fruit firmness significantly declined during ripening, with the greatest reduction between the 28 and 35 days stages. The decrease in firmness correlated with an extensively deformed microstructure in the parenchyma tissues and positively correlated with reductions in the contents of fruit cell wall materials and molecular weight in cell wall polysaccharide. Cellulase, α-galactosidase, polygalactosidase and pectin methylesterase showed higher activities during 28 days; whereas, the activities of β-galactosidase were higher during 35 days. These results indicate that cell wall-related processes are a key feature of early softening in L. barbarum L.  相似文献   
996.
中央美院青岛创业中心项目为角部重叠的回字形山地建筑,采用了框架-剪力墙结构体系.主体建筑结构总高度为54m,坐落在三个台地上,每两个相邻台地高差10m左右.掉层处采用"掉层脱开式且有拉梁"的方式进行结构布置.结合山地建筑结构的基本概念和受力特点,介绍了本项目的结构处理方式和设计难点,采用PKPM,MIDAS Building,SAUSAGE软件对结构进行了弹性反应谱法分析、弹性时程分析、动力弹塑性时程分析和抗震性能设计,同时针对各种不利因素采取了相应的加强措施,确保了结构安全.  相似文献   
997.
陈薇 《建筑学报》2021,(10):64-69
建筑师职业需要终身学习是不二法则.彼时,杨廷宝先生坚持和践行循序发展,成为一代宗师,也是我们向这位伟大建筑师致敬的缘由之一;在当代,循序发展或许受到挑战,时代节奏和社会需求及学习资源的获得,使得我们的学习和工作方式及要求发生了改变,我称之为关联学习.但是,无论是杨时代的循序发展,还是当代的关联学习,都指向了对于成为中国建筑师如何解决本土问题以及传承和发扬一切优秀传统的讨论.本文将对此进行研究,分享思考,以期在纪念和致敬杨廷宝先生诞辰120年之际,能够对于当下建筑师培养的路径略有前行和开阔.  相似文献   
998.
Huang  Yu-Ting  Sun  Yuan-Bo  Zeng  Qing-Rui  Feng  Wei 《Journal of Materials Science》2021,56(36):19870-19883

Novel organic–inorganic layer-by-layer (LbL) multilayers for visible-light phototropy, comprised of polyvinylpyrrolidone (PVP) and phosphomolybdic acid (PMoA), were fabricated via layer-by-layer (LbL) assembly with ultrasonic pretreatment. The characterizations revealed that the Keggin spatial geometry of the PMoA was still maintained in the final ultrasonic-assisted LbL thin films, which promoted halogenesis between the PVP and PMoA. Intriguingly, instead of destroying the PVP thin film, the ultrasonic pretreatment process successfully dispersed the PMoA in the PVP thin film with a median size of approximately 3.6 nm. Thanks to the dispersion of the PMoA particles, the photochromic capabilities of the ultrasonic-assisted PVP/PMoA LbL thin films gained remarkable improvement. Moreover, decreasing the size of the PMoA particles to quantum dots (10–3.4 nm) induces an up-conversion and dielectric confinement effect, which increases the intensity of the absorption peak (0.235 increased to 0.45) while narrowing the emission energy (2.51 eV narrowed to 2.23 eV). At the same time, the size reduction also extended the range of the absorption wavelength, increases the characteristic absorption intensity, and accelerates the coloration rate over the same illumination period.

  相似文献   
999.
Du  Wei  Wang  Yibo  Xu  Wei  Ma  Jian 《Scientometrics》2021,126(12):9369-9391
Scientometrics - Patents, as technological innovation with commercial values, play a significant role for increasing enterprise and national competitiveness. Personalized recommendation in online...  相似文献   
1000.
In this study, the mechanical performance of the rice husk ash-reinforced tin-0.7 copper composite solder was investigated. 0.01 wt.%, 0.05 wt.% and 0.1 wt.% of rice husk ash (RHA) were added to the solder matrix to prepare the composite solders. In order, to replace the costly electroless nickel immersion gold surface finish on the copper substrate, the effect of electroless nickel immersion silver (ENIAg) as the surface finish was studied. The differential scanning calorimetry (DSC) analysis showed that the composite solder exhibited lower melting temperature relative to the plain solder owing to the inclusion of rice husk ash. Shear strength analysis was carried out to investigate the influence of rice husk ash and electroless nickel immersion silver surface finish on the shear strength of the developed composite solders. The results proved that the rice husk ash failed to enhance the shear strength of tin-0.7 copper lead-free solder with the plain solder exhibiting the highest shear strength.  相似文献   
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