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971.
Chul Soon Yong Mi-Kyung Lee Young-Joon Park Kyung-Hwan Kong Jing Ji Xuan Ji-Hyun Kim 《Drug development and industrial pharmacy》2013,39(7):615-622
To improve the oral bioavailability of poorly water-soluble ibuprofen with poloxamer and menthol, the effects of menthol and poloxamer 188 on the aqueous solubility of ibuprofen were investigated. The dissolution and pharmacokinetic study of ibuprofen delivered by the ibuprofen-loaded preparations composed of poloxamer 188 and menthol were then performed. In the absence of poloxamer, the solubility of ibuprofen increased until the ratio of menthol to ibuprofen increased from 0:10 to 4:6 followed by an abrupt decrease in solubility above the ratio of 4:6, indicating that four parts menthol formed eutectic mixture with six parts ibuprofen. In the presence of poloxamer, the solutions with the same ratio of menthol to ibuprofen showed an abrupt increase in the solubility of ibuprofen. The poloxamer gel with menthol/ibuprofen ratio of 1:9 and higher than 15% poloxamer 188 showed the maximum solubility of ibuprofen, 1.2 mg/mL. The simultaneous addition of menthol and poloxamer 188 significantly improved the dissolution rates of ibuprofen from aqueous solution due to the ibuprofen solubility-improving effect of menthol in the presence of poloxamer. Furthermore, the ibuprofen-loaded preparation with menthol and poloxamer 188 gave significantly higher initial plasma concentrations, Cmax, and AUC of ibuprofen than did the preparation without menthol and poloxamer 188, indicating that the simultaneous addition of menthol and poloxamer 188 could improve the oral bioavailability of ibuprofen in rats. In modern pain management it is always desirable for the ibuprofen-loaded preparation with poloxamer 188 and menthol to show a rapid onset of action with a minimal phase of lag time to feel the decreased pain. From an industry point of view, it is more desirable for a formulation to be fast acting, easy to use, and cost effective. Thus, the ibuprofen-loaded preparation with poloxamer 188 and menthol was a more effective oral dosage form for poorly water-soluble ibuprofen. 相似文献
972.
以山西某医院机电安装工程中的管线安装为背景,对大型公用工程所采用的管线综合平衡技术及其施工准备、确认、实施、运用及应用效果进行阐述,可为今后的类似工程施工提供参考. 相似文献
973.
Yinzhou YanLingfei Ji Yong BaoYijian Jiang 《Journal of Materials Processing Technology》2012,212(6):1257-1270
A major challenge in laser percussion drilling of thick-section ceramics is to obtain a low taper and low spatter deposition hole leading to high quality post-processing. In order to achieve the fine hole drilling, it is important to understand the mechanism of laser percussion drilling. In this paper, an experimental and numerical study on laser percussion drilling was carried out. A two-dimension (2D) axisymmetric finite element (FE) model for simulation of temperature field and proceeding of hole formation during percussion drilling was developed. The FE model was validated by the corresponding experiment. Furthermore, a theoretical model for evaluation of temperature at melt front and velocity of melt ejection was presented in order to further validate the FE model and study the spatter deposition. The effects of laser peak power, pulse duty cycle and pulse repetition rate on hole diameter and spatter deposition were investigated by the developed models and experiments, in which the simulated results were in good agreement with the experiments. The study indicated that the size and temperature of the melt front significantly affected the hole diameter formation and spatter deposition during laser percussion drilling. The characteristic of melt front was mainly determined by the employed laser peak power, pulse repetition rate and pulse duty cycle. Based on the experimental and numerical study, the process parameters were optimised and a drilled-hole with low taper and low spatter deposition was obtained using a 3.5 kW CO2 laser. A microstructural and element compositional study was also performed in this work, by which the characteristics of microstructure and element composition in HAZ around laser drilled hole were revealed. 相似文献
974.
975.
当复杂形式的建筑设计日益普遍,几何学对于建筑师理解复杂建筑形体的操作实质变得前所未有的重要,并以此催发几何学与建筑学关联性的重新审视。本文从梳理两者关系的演变历程出发,分析了当代数字化建筑实践的4种几何建构策略——几何生形、几何转化、协同模拟和几何重构,并结合具体案例研究,指出面向建筑本体需求的数字化几何思维是建筑学传统的回归,可以为数字化建筑设计提供更为合理的认识和参考。 相似文献
976.
977.
Qianjie Li Shuaishuai Ji Dongdong Wang Jiangyuan Zhu Leiyu Li Wei Wang Min Zeng Zhipeng Hou Xingsen Gao Xubing Lu Qiliang Li Jun-Ming Liu 《Journal of the European Ceramic Society》2021,41(1):387-393
In this work, a series of novel lead-free (1-x)Bi0.83Sm0.17Fe0.95Sc0.05O3-x(0.85BaTiO3-0.15Bi(Mg0.5Zr0.5)O3) [(1-x)BSFS-x(BT-BMZ), x = 0.45?0.85] relaxor ceramics were prepared by solid phase sintering, and their dielectric properties and energy storage performances were explored. It was revealed that all the samples have a dense structure with pure pseudo-cubic phase. With the increase of x, the ferroelectric hysteresis loop is gradually slimmed accompanied by a decreasing polarization, indicating an enhanced relaxor behavior. Moreover, the electric breakdown strength increases linearly with x due to the fine grain size and enhanced relative density. Interestingly, a large recoverable energy density (~3.2 J/cm3) with an outstanding efficiency (~92 %) is achieved under an electric field ~206 kV/cm for the optimized component x = 0.75, which is superior to other reported lead-free ceramic systems. Moreover, the optimized ceramics of 0.25BSFS-0.75(BT-BMZ) show good thermal stability (25?100 °C) and excellent fatigue endurance (cycle number: > 105) in energy storage performances. This work opens up a new route to tailor lead-free dielectric ceramics with high energy storage properties. 相似文献
978.
Fabrication of ZnS/C microsphere composites with enhanced electromagnetic wave absorption properties
Xing Honglong Wang Yin Bai Linghan Ji Xiaoli Yang Ping 《Journal of Materials Science: Materials in Electronics》2022,33(25):20021-20034
Journal of Materials Science: Materials in Electronics - For electromagnetic wave-absorbing materials, organic-derived carbon materials and metal sulfides are highly preferred. In this paper, ZnS/C... 相似文献
979.
In hot climate, phase change material (PCM) can be incorporated into building envelopes to reduce heat gain through the building envelopes and therefore reduce its cooling demand. In this study, the energy performance of building envelopes integrated with PCM has been explored using a popular dynamic building performance simulation package, EnergyPlus, and the energy saving mechanism of PCM was investigated. The simulation results reflected that PCM could effectively help to reduce the building's annual energy consumption by 20.9% for Guangzhou, China. In addition, for the Guangzhou city, 27°C transition temperature, smaller thermal conductivity of roof, and higher amount of PCM can all help to improve the building's energy performance. Additionally, it is suggested that in real building development/retrofit projects, the selection of PCM needs to be based on both their thermal properties and the local climatic conditions of the building. 相似文献
980.
Qingxin Lai Yuli Xiong Xing Ji Jiangna Guo Peng Xiao Yunhuai Zhang 《International Journal of Hydrogen Energy》2021,46(44):22789-22798
Construction of heterostructured electrocatalyst with interface effect is an effective strategy for enhancing the alkaline hydrogen evolution efficiency, whereas this process often requires complex treatments. Herein, we proposed a one-step electrodeposition method to obtain heterostructured CoNi-LDH@NiCo alloy on Ni foam (NF) through a competition reduction between NO3? group and metal cations in the electrolyte. The HER performance for the CoNi-LDH@NiCo alloy achieved the current density of 10 mA cm?2 at overpotential of 69 mV in 1 M KOH solution, improved 60% for η10 by comparing with the pristine NiCo alloy. Utilizing the specialized adsorption of CoNi-LDH for H2O and the featured attractiveness of NiCo alloy for H atom, the interface effect of the heterostructure electrocatalyst accelerated the dissociation of water molecules and elevated the catalytic kinetics dramatically. This work points out a potential approach towards the easy construction of inexpensive heterostructured electrocatalysts for HER activity in alkaline medium. 相似文献