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991.
992.
在现阶段的公民道德环境中,还存在封建的人治传统、鱼龙混杂的舆论信息、市场经济的唯利倾向等消极因素,这就要求我们必须构建良好的公民道德环境。新时期的公民道德环境各要素,包括行政奖惩环境、法律保障环境、舆论引导环境、风气熏陶环境和教育培养环境在内,要进行系统的优化。具体来说,进行优化要从加强媒体管制、营造和谐气氛以及加强道德教育等方面入手。 相似文献
993.
Lan Yang Xiao He Zhiying Zeng Jiakun Tang Dongmei Qi Huijie Ma Hui Chen Xinghai Ning Xuli Feng 《Chemical science》2021,12(24):8394
Nucleus-targeted therapy holds great promise in cancer treatment; however, a lack of effective nucleus-specific delivery significantly limits its application potential. Here, we report a nucleus-targeted synergistic chemo-photodynamic therapy based on the self-assembly of chlorin e6 (Ce6) and doxorubicin (DOX) tuned by clickable dibenzocyclooctyne (DIBO) functionalized lysine (D-K) and subsequent reaction with crosslinkers. The assembled nanodrugs with high loading efficiency and long-term stability show enhanced cellular uptake and accumulation in the nucleus, resulting in greatly improved in vitro and in vivo chemo-photodynamic efficacy. Notably, D-K can promote the rapid self-assembly of Ce6 and DOX in aqueous solution, avoiding the introduction of organic solvents or tedious preparations. In addition, the introduction of the DIBO group can effectively expand the types of self-assembly material and enhance the self-assembly behaviour through a copper-free click reaction. Therefore, we present an effective nucleus-targeted combination drug delivery strategy, which has great potential in the treatment of many diseases.A highly efficient nucleus-targeted multi-drug delivery nanoplatform based on clickable amino acid tuned self-assembly of chlorin e6 and doxorubicin has been prepared for enhanced photodynamic therapy and chemotherapy. 相似文献
994.
Preparation of ordered array of nanoscopic gold rods by template method and its optical properties 总被引:5,自引:0,他引:5
S.L. Pan D.D. Zeng H.L. Zhang H.L. Li 《Applied Physics A: Materials Science & Processing》2000,70(6):637-640
Porous aluminum oxide membranes with pore diameters smaller than 20 nm were prepared by anodization of aluminum. Using these porous membranes as a template, we fabricated uniform gold cylinder arrays by electrodeposition of gold into the pores. All cylinders in the array were parallel, with their long axes perpendicular to the surface of the template. Electron microscopy, including transmission electron microscopy (TEM) and scanning electron microscopy (SEM), were employed to characterize the morphology of the templates and the fabricated nanometer scale of cylinder arrays. The extinction spectra of the arrays along the longer axes showed that the extinction maximal (5max) shifted to a short wavelength and strengthened when the aspect ratio (l/d) of the cylinders increased. The dependence of the maximal (5max) on the size was explained qualitatively by using the approximate dynamical Maxwell-Garnett model, and the calculated results were compared with the experimental ones. 相似文献
995.
996.
论述了向量丛上联络的性质,得到流形M与欧氏空间局部等距的一个充要条件,并且证明了M作为切丛TM中的子流形时,M的法丛与TM是等距的。 相似文献
997.
In recent years,low-dimensional materials have received extensive attention in the field of electronics and optoelectronics.Among them,photoelectric devices based on photoconductive effect in low-dimensional materials have a broad development space.In contrast to positive photoconductivity,negative photoconductivity(NPC)refers to a phenomenon that the conductivity decreases under illumination.It has novel application prospects in the field of optoelectronics,memory,and gas detection,etc.In this paper,we review reports about the NPC effect in low-dimensional materials and systematically summarize the mechanisms to form the NPC effect in existing low-dimensional materials. 相似文献
998.
Wen-Jin Yin Xiao-Long Zeng Bo Wen Qing-Xia Ge Ying Xu Gilberto Teobaldi Li-Min Liu 《Frontiers of Physics》2021,16(3):33501
Heterostructure is an effective approach in modulating the physical and chemical behavior of materials. Here, the first-principles calculations were carried out to explore the structural, electronic, and carrier mobility properties of Janus MoSSe/GaN heterostructures. This heterostructure exhibits a superior high carrier mobility of 281.28 cm2·V−1·s−1 for electron carrier and 3951.2 cm2·V−1·s−1 for hole carrier. Particularly, the magnitude of the carrier mobility can be further tuned by Janus structure and stacking modes of the heterostructure. It is revealed that the equivalent mass and elastic moduli strongly affect the carrier mobility of the heterostructure, while the deformation potential contributes to the different carrier mobility for electron and hole of the heterostructure. These results suggest that the Janus MoSSe/GaN heterostructures have many potential applications for the unique carrier mobility. 相似文献
999.
Rui Wang Ying Chang Miao Miao Zhiyi Zeng Hongyan Chen Haixia Shi Danning Li Lifang Liu Youjin Su Peng Han 《Entropy (Basel, Switzerland)》2021,23(6)
Many studies have shown that b values tend to decrease prior to large earthquakes. To evaluate the forecast information in b value variations, we conduct a systematic assessment in Yunnan Province, China, where the seismicity is intense and moderate–large earthquakes occur frequently. The catalog in the past two decades is divided into four time periods (January 2000–December 2004, January 2005–December 2009, January 2010–December 2014, and January 2015–December 2019). The spatial b values are calculated for each 5-year span and then are used to forecast moderate-large earthquakes (M ≥ 5.0) in the subsequent period. As the fault systems in Yunnan Province are complex, to avoid possible biases in b value computation caused by different faulting regimes when using the grid search, the hierarchical space–time point-process models (HIST-PPM) proposed by Ogata are utilized to estimate spatial b values in this study. The forecast performance is tested by Molchan error diagram (MED) and the efficiency is quantified by probability gain (PG) and probability difference (PD). It is found that moderate–large earthquakes are more likely to occur in low b regions. The MED analysis shows that there is considerable precursory information in spatial b values and the forecast efficiency increases with magnitude in the Yunnan Province. These results suggest that the b value might be useful in middle- and long-term earthquake forecasts in the study area. 相似文献
1000.