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41.
Yongsong Luo Benhai Yu Youchao Tu Ying Liang Yonggang Zhang Jinping Liu Jialin Li Zhijie Jia 《Materials Research Bulletin》2008,43(8-9):2166-2171
Cu2O nanocactuses were synthesized via a simple, low-temperature, and no time-consuming wet chemical route. The synthesized products were systematically studied by X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the formation of Cu2O nanocactuses was strongly depended on the addition of CTAB and NaOH. The structural evolution of the cactuslike Cu2O was found to follow dissolution and recrystallization processes. It is noteworthy that the stepwise synthetic procedure was crucial to the growth of the final nanoarchitectures. UV–vis spectrum was also used to estimate the absorption and photodegradation ability of the nanocactuses. 相似文献
42.
通过对国产纸膜和日本滤纸膜材料的分析研究,研制出NIMTE异相膜,并在空气能量回收装置使用过程中对风压、空气流量、热流方向与热交换效率、回收能量、能效及安全性的关系进行分析,设计出能够更好发挥异相膜使用效果的传热膜机芯,有效提高空气能量回收装置的综合性能。 相似文献
43.
Fei Li Heqiu Zhang Lizhong Hu Yingmin Luo Yu Zhao Yu Qiu Jiuyu Ji Lunlun Yue 《Journal of Materials Science: Materials in Electronics》2013,24(12):4812-4816
One-dimensional (1D) ZnO microwires were successfully synthesized by chemical vapor deposition and their structural and morphological properties were analyzed by X-ray diffraction and scanning electron microscopy, demonstrating that the microwires were single crystalline with perfect hexagonal structure and smooth surface. Using these 1D microstructures, we fabricated a novel ZnO-based ethanol gas sensor. Operating at room temperature, the sensor was found to have good sensing characteristics. The reliability and stability of the sensor could be improved by connecting multiple 1-wire devices (1-WD) in parallel into a multi-wires device. In interior natural lighting environment and under 3 V bias, the response and recovery time of the 1-WD to 200 ppm ethanol gas were <10 s and about 300 s, respectively, and the minimum and maximum detection limit were about 2 and 200 ppm, respectively. A sensing model was proposed for discussing the performance of the sensor. The simplicity in fabrication, low power consumption and low cost make the sensor suitable for practical application in many fields, especially in identifying driving under the influence and chemical industry monitoring. 相似文献
44.
Chen J Luo Y Hong L Ling Y Pang J Fang Y Wei K Gao X 《Journal of materials science. Materials in medicine》2011,22(3):547-555
A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited
bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)–hydroxyapatite
(PCL–HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine
that belongs to the bisphosphonates family. The PCL/HA–AL microspheres were prepared with solid/oil/water emulsion technique,
which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA–AL complex was built in the
PCL matrix. The spherical PCL/HA–AL microspheres were characterized with its significantly improved encapsulation efficiency
of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of
these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA–AL
microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion,
by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA–AL microspheres have the potential to be used as
an injectable vehicle for local therapy of bone defect. 相似文献
45.
系统以工控机为中心,配以高性能的模块化外设组成一体化的计算机控制系统。采用温度控制外环和电流平衡控制内环的双环路结构来具体实现交流电弧炉温度和三相电流平衡的智能集成控制。外环采用模糊、神经网络和优化决策共同控制,内环则采用模糊专家解耦控制。系统能实时自适应炉况状态的变化,提高生产效率,降低电能及电极消耗。实际运行证明该系统具有良好的鲁棒性和实时性。 相似文献
46.
本文在现有网络分析的基础上,进行了EDGE数据网的规划,并通过仿真对规划结果进行了验证,最后对语音和数据网络的资源配置方法进行了研究,提出了相应的资源配置方法。 相似文献
47.
Jia-Shun Liu Yi-Kun Zhang Hui Tang Li-Bo Zhang Ben-Qiang Yang Ying Yan Li-Min Luo Yang Chen 《核技术(英文版)》2021,32(8):23-33
Tomographic perfusion imaging is a significant imaging modality for stroke diagnosis.However,the low rotational speed of the C-arm(6-8 s per circle)is a chal-le... 相似文献
48.
49.
Shuai Wang Wei-jian Chen Zheng-zhi Zhao Xiao-long Zhao Xiao-yang Luo Qiang Wang 《钢铁研究学报(英文版)》2021,28(6):762-772
The influence of microstructural characteristics on Lüders strain and mechanical properties was explored by means of altering thermo-mechanical circumstances in... 相似文献
50.
多功能油层保护剂JQD的研制与应用 总被引:2,自引:0,他引:2
针对新疆小拐油田裂缝-孔隙型储层特点,开发研制了一种新型的兼具防漏堵漏及油层保护功能的JQD处理剂。该处理剂具有较好的油溶率、酸溶率,与现有钻井完井液体系配伍性良好,加工粒径可调,对1—4mm的裂缝堵漏效果良好。动态损害实验表明,JQD体系的岩心渗透率恢复值不小于80%。现场试验三口表明,JQD与钻井液配伍性良好,防漏堵漏效果显著,性能调整及维护方便,起下钻及电测顺利。三口井投产后,两口井产量分别为30和28t/d,一口井产气量为1.1×10~4m~3/d,说明储层得到了有效的保护,实现了“堵得住、解得开”的目标。 相似文献