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61.
Xiao-Lei Qiu Zi-Rui Fan Yang-Yang Liu Ding-Fu Wang Shi-Xin Wang Chun-Xia Li 《International journal of molecular sciences》2021,22(8)
A self-nanoemulsifying drug delivery system (SNEDDS) was developed to enhance the absorption of heparin after oral administration, in which heparin was compounded with phospholipids to achieve better fat solubility in the form of heparin-phospholipid (HEP-Pc) complex. HEP-Pc complex was prepared using the solvent evaporation method, which increased the solubility of heparin in n-octanol. The successful preparation of HEP-Pc complex was confirmed by differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, NMR, and SEM. A heparin lipid microemulsion (HEP-LM) was prepared by high-pressure homogenization and characterized. HEP-LM can enhance the absorption of heparin after oral administration, significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT) in mice, and reduce fibrinogen (FIB) content. All these outcomes indicate that HEP-LM has great potential as an oral heparin formulation. 相似文献
62.
Ningqin Deng He Tian Jian Zhang Jinming Jian Fan Wu Yang Shen Yi Yang Tian-Ling Ren 《半导体学报》2021,42(8):21-33
Black phosphorus(BP),an emerging two-dimensional material,is considered a promising candidate for next-genera-tion electronic and optoelectronic devices due to in-plane anisotropy,high mobility,and direct bandgap.However,BP devices face challenges due to their limited stability,photo-response speed,and detection range.To enhance BP with powerful electric-al and optical performance,the BP heterostructures can be created.In this review,the state-of-the-art heterostructures and their electrical and optoelectronic applications based on black phosphorus are discussed.Five parts introduce the perform-ance of BP-based devices,including black phosphorus sandwich structure by hBN with better stability and higher mobility,black phosphorus homojunction by dual-gate structure for optical applications,black phosphorus heterojunction with other 2D materials for faster photo-detection,black phosphorus heterojunction integration with 3D bulk material,and BP via As-doping tunable bandgap enabling photo-detection up to 8.2 μm.Finally,we discuss the challenges and prospects for BP electric-al and optical devices and applications. 相似文献
63.
64.
Neural Computing and Applications - Natural language summaries of codes are important during software development and maintenance. Recently, deep learning-based models have achieved good... 相似文献
65.
Qiang Wang Lei Shen Tong Xue Gao Cheng Cheng Zhi Huang Hong Jin Fan Yuan Ping Feng 《Advanced functional materials》2021,31(2):2002187
The {100} facet of single-crystalline TiO2(B) is an ideal platform for inserting Li ions, but it is hard to be obtained due to its high surface energy. Here, the single-crystalline TiO2(B) nanobelts from H2Ti3O7 with nearly 70% {100} facets exposed are synthesized, which significantly enhances Li-storage capacity. The first-principle calculations demonstrate an ab in-plane 2D diffusion through the exposed {100} facets. As a consequence, the nanobelts can significantly accommodate Li ions in LiTiO2 formula with specific capacity up to 335 mAh g−1, which is in good agreement with the electrochemical characterizations. Coating with conductive and protective poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), the cut-off discharge voltage is as low as 0.5 V, leading to a capacity of 160.7 mAh g−1 after 1500 cycles with a retention rate of 66% at 1C. This work provides a practical strategy to increase the Li-ion capacity and cycle stability by tailoring the crystal orientation and nanostructures. 相似文献
67.
利用信息可视化软件Cite Space,将2007年至2021年间WOS数据库中与城市公园小气候热舒适性相关的1445篇文献作为研究对象进行分析,制作相关知识图谱,可以实现研究前沿、研究热点、未来的发展趋势的可视化,为以后的研究提供参照. 相似文献
68.
Mine Water and the Environment - Treating mine water as a resource is the only way to alleviate water shortage and the environmental pollution issues generated at mining sites in areas of northern... 相似文献
69.
Baowei Fan Yonghao Zeng Yaoyuan Zhang Jianfeng Pan Wenming Yang Yuanguang Wang 《International Journal of Hydrogen Energy》2021,46(13):9234-9251
The purpose of the present paper is to investigate the hydrogen injection strategy on the combustion performance of a natural gas/hydrogen rotary engine. Considering that apex seal leakage (ASL) is an inevitable problem in the actual working process of a rotary engine, the action of ASL cannot be ignored for an in-depth study of its combustion performance. Therefore, in this paper, a 3D dynamic simulation model that put the effect of ASL into consideration was established. Furthermore, based on the established 3D model, the combustion process of a natural gas/hydrogen rotary engine under various hydrogen injection angle (HIA) and hydrogen injection timing (HIT) was investigated. The results indicated that the hydrogen jet flow first impacted on the rotor wall after entering the cylinder, and then diffused under the action of the vortexes in the cylinder. Therefore, the HIA and HIT could change the hydrogen distribution by changing the hydrogen impact location and the intensities of the vortexes in the cylinder. In addition, the ideal hydrogen distribution at the ignition timing which could improve the combustion efficiency was given. That is, under the premise of ensuring minimized hydrogen leakage, the hydrogen should mainly distribute in the middle and the front of the cylinder, and a high hydrogen concentration is maintained near the spark plug. 相似文献
70.
Hrvoje Mikulčić Jakov Baleta Xuebin Wang Jin Wang Fengsheng Qi Fan Wang 《International Journal of Hydrogen Energy》2021,46(45):23548-23563
Ammonia appears to be a potential alternative fuel that can be used as a hydrogen vector and fuel for gas turbines and internal combustion engines. Chemical mechanisms of ammonia combustion are important for the development of ammonia combustion systems, but also as a mean of investigation of harmful NOx emissions, so they can be minimized. Despite of large body of experimental and modelling work on the topic of ammonia combustion, there is still need for additional investigation of combustion kinetics.The object of this work is further numerical study of ammonia combustion chemistry under conditions resembling industrial ones. After literature review, three mechanisms of ammonia combustion that also include carbon chemistry are used for simulation of experimental premixed swirl burner with the aim of evaluating their performance. San Diego mechanism, that was also the most detailed one, proved to be the best in terms of emissions, but neither one of the models was able to accurately reproduce CO emission after equivalence ratio went beyond 0.81. It was also observed that oxygen is excessively consumed. This study contributes to the current knowledge by providing new insights in ammonia burning conditions closely resembling those in industrial applications, and consequently is expected that insights obtained will help in the design of real industrial burning systems. 相似文献