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81.
Glioblastoma is an extremely difficult clinical indication with very few therapeutic choices. In this study, a nanoparticle is constructed featuring high red absorbance and selective penetration of the blood–brain barrier (BBB) at the tumor site. This nanoparticle can provide timely activation of the adenosine receptor on the BBB to allow self‐passage and accumulation in the tumor. The nanoparticle converts pulsed laser energy into a shockwave via photoacoustic (PA) cavitation to achieve localized mechanical damage and thus yields a precision antitumor effect. In addition to its therapeutic function, the nanoparticle‐mediated PA process can also generate images that provide valuable information regarding tumor depth, size, and vascular morphology to inform treatment planning and monitoring. The results show that the nanoparticles can be efficiently delivered into the glioblastoma via intravenous infusion and this PA shockwave therapy can selectively destroy glioblastoma tumors with no observable side effects on normal tissue. 相似文献
82.
World Wide Web - Rule mechanism has been widely used in many areas, such as databases, artificial intelligent and pervasive computing. In a rule mechanism, rule activation decides which rules are... 相似文献
83.
Solid acids as a substitution for hazardous liquid acids (e.g., HF and H2SO4) can promote many important reactions in the industry, such as carbon cracking, to proceed in a more sustainable way. Starting from a zirconium‐based metal‐organic framework (UiO‐66 nanocrystals), herein a transformative method is reported to prepare micro/mesoporous yttria‐stabilized zirconia (YSZ) encapsulated inside a mesoporous silica shell. It is then further demonstrated that the resultant reactor‐like catalysts can be used for a wide range of catalytic reactions. The acidity of the YSZ phase is found with rich accessible Lewis acid and Brønsted acid sites and they display superior performances for esterification (acetic acid and ethanol) and Friedel‐Crafts alkylation (benzylation of toluene). After being loaded with different noble metals, furthermore, hydrogenation of CO2 and a one‐pot cascade reaction (nitrobenzene and benzaldehyde to N‐benzylaniline) are used as model reactions to prove the versatility and stability of catalysts. Based on the findings of this work, it is believed that this class of reactor‐like catalysts can meet future challenges in the development of new catalyst technology for greener heterogeneous catalysis. 相似文献
84.
85.
Ming Liu Qin Le Liu Lin Peng Haoping Liu Xuedong Chao Jianwei 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(6):1085-1090
Protection of Metals and Physical Chemistry of Surfaces - Three-dimensional molecular dynamics (MD) simulation is conducted to understanding the dynamics processes of atomic-scale friction, which... 相似文献
86.
Dr. Jiayao Y. Wang Dr. Jiaqi Q. Li Prof. Dr. Yumei M. Xiao Prof. Dr. Bin Fu Prof. Dr. Zhaohai H. Qin 《ChemMedChem》2020,15(5):404-410
Mitochondrial oxidative damage and dysfunction contribute to a wide range of human diseases. Considering the limitation of conventional antioxidants and that mitochondria are the main source of reactive oxygen species (ROS) which induce oxidative damage, mitochondria-targeted antioxidants which can selectively block mitochondrial oxidative damage and prevent various types of cell death have been widely developed. As a lipophilic cation, triphenylphosphonium (TPP) has been commonly used in designing mitochondria-targeted antioxidants. Conjugated with the TPP moiety, antioxidants can achieve more than 1000-fold higher mitochondrial concentration depending on cell membrane potentials and mitochondrial membrane potentials. Herein we discuss the deficiencies of conventional antioxidants and the advantages of mitochondrial targeting, and review various types of TPP-based mitochondria-targeted antioxidants. These provide theoretical and background support for the design of new anti-oxidant. 相似文献
87.
溶剂萃取法是盐湖提锂的重要工艺方法。采用磷酸三丁酯(TBP)/1-丁基-3-甲基咪唑双三氟甲基磺酰亚胺盐([C4mim][NTf2])离子液体体系对高镁锂比盐湖卤水中的锂进行萃取分离提取实验,对负载有机相的洗涤和反萃过程进行了研究。萃取实验:在TBP与[C4mim][NTf2]体积比为9∶1、相比(有机相与水相的体积比)为2∶1条件下,锂离子与其他离子的分离系数分别为β(锂/钠)=94.70、β(锂/钾)=148.85、β(锂/镁)=131.81。洗涤实验:系统考察了洗涤剂种类及浓度、相比、洗涤次数等因素对杂质离子洗脱率的影响,结果发现氯化锂和盐酸的混合溶液是从负载有机相中洗涤除去杂质离子的有效洗涤剂。洗涤过程适宜条件:洗涤剂中氯化锂浓度为4 mol/L、盐酸浓度为0.5 mol/L,相比为5∶1,洗涤次数为2次。反萃实验:用稀盐酸(1.0 mol/L)对负载有机相进行反萃取,在相比为1∶1条件下,单级反萃率达到97.81%。研究表明,离子液体体系作为一种新型萃取体系,在高镁锂比盐湖卤水中提取锂具有较好的应用前景。 相似文献
88.
采用冷态物理模型结合商用CFD(Computational Fluid Dynamics)软件,对山东某火电厂300 MW机组配套托盘塔的流场和阻力特性进行了研究,取得了孔板阻力损失与液气比之间的二次函数关系。研究结果表明,塔内两相流场分布合理,入口处液滴受烟气的拖拽作用形成明显的干湿界面,负荷和液气比是影响脱硫塔阻力的重要因素。当液气比一定时,托盘上方能够维持相对稳定的持液层及鼓泡过程;满负荷运行时,脱硫塔阻力损失约为1600 Pa,其中孔板占1/4,持液层占3/4。拟合获得了托盘区阻力损失同液气比之间的关系,为托盘塔的应用、运行及优化提供了理论指导。 相似文献
89.
90.
Xiatong Qin Weihao Liu Genqi Liu Chenrui Ren Chenhui Liu Huanhuan Li Yunlei Cao 《应用聚合物科学杂志》2020,137(42):49299
A novel molecularly imprinted two-dimensional (2-D) photonic crystal hydrogels (MIPH) for sensitive and label-free recognition of 2,4-dichlorophenol (2,4-DCP) was prepared. The 2-D photonic crystal template was fabricated by using air-water interface self-assembly method. And then the template was embedded with molecularly imprinted polymer, which was synthesized with 2,4-DCP as imprinted molecules, dimethyl sulfoxide as solvent, acrylic acid and acrylamide as functional monomers, N,N-methylene bis acrylamide as cross-linker, azobisisobutyronitrile as initiator. The imprinted molecules were removed by 0.01 M ammonia solution. The results indicated that the 2,4-DCP molecularly imprinted 2-D photonic crystal hydrogels has good response and recognition ability to 2,4-DCP. When the molar ratio of cross-linking density of MIPH is 2.3% and the molar ratio of imprinting molecule is 5.0%, the change of Debye ring diameter is the largest. The diameter of Debye ring increased by 7.1 mm when the concentration of 2,4-DCP changed from 0 to 1 × 10−6 M, and the particle spacing of MIPH reduced 38 nm. In addition, the diameter of the Debye ring hardly changed in the solution of analogues of 2,4-DCP such as, phenol, 2-chlorophenol, 2,4,6-trichlorophenol and so on, indicating that the MIPH has highly sensitivity and specificity. 相似文献