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991.
992.
氧化物、盐类在氧化物载体表面的自发分散是一种广泛存在的现象,文献中已报导过大量氧化物和盐类在高比表面载体上分散的研究结果['-3]TIO。作为一种较新型的载体,与Y-AI。O。、硅胶等传统载体相比,有许多不同特性.活性组分在TIO。表面的分散状态及所得催化剂的性能已有不少报导['-'],但所用的TIOZ主要是较高比表面的锐钛矿型TIOZ(刘金红石型TIO。(r)和锐钛矿型TIOZ(a)的结构不同,它是高温生成相,比表面较小['].氧化物在金红石上的分散行为仍未见报导.我们制备了三种具有不同比表面的TIO水),系统地研… 相似文献
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996.
本文比较了在标准石墨管,热解涂层和全热解石墨管中钒的吸收信号形状。用全热解石墨管和EDTA铵盐作基体改进剂,直接测定水系沉积物中痕量钒。方法的特征量为61pg/0.0044A。 相似文献
997.
Lin Jiacheng Li Qianqian Zeng Xiaodong Chen Ziyang Ding Qihang Li Yang Zhou Hui Meng Xianli Chen Deliang Deng Zixin Hong Xuechuan Xiao Yuling 《中国科学:化学(英文版)》2020,63(6):766-770
Osteosarcoma is the most common primary malignant tumor of bone, particularly among children and adolescents. Advances in imaging, surgical techniques, and implants have dramatically reduced the need for amputation in the past three decades.Recently, in vivo fluorescence imaging in the second near-infrared window(NIR-II, 1,000–1,700 nm) shows impressive advantages of deeper tissue penetration and higher spatial resolution, which makes it a promising tool for the early diagnosis and post-operative observation of Osteosarcoma. To the best of our knowledge, this paper is the first time to develop a novel NIR-II fluorescence probe conjugated with an osteosarcoma targeted oligopeptide for molecular tumor imaging in a xenograft orthotopic osteosarcoma mouse model. 相似文献
998.
Conjugated linoleic acids (CLA) have been a subject of extensive investigation for their anticarcinogenic, hypolipidemic, antiatherosclerotic and immune-enhancing activities. Stability of CLA in foods has not received much attention by both academics and industry. Although CLA has shown many beneficial effects, its decomposition must be prevented when CLA in foods is processed, stored and transported. However, no study to date has addressed the stability of CLA in foods. The present study was carried out further to examine the stability of CLA in egg yolk during the storage and frying, using gas liquid chromatography (GLC) and silver ion high-performance liquid chromatography (Agt-HPLC). The eggs, containing 4.0% CLA per gramme of egg yolk, were 40s. Either storage for 6 months or frying for 40 s did not significantly change the composition of CLA in egg yolk. However, the degradation of CLA was statistically significant when the CLA components of egg yolk protected CLA from degradation. It is concluded that CLA is well preserved in egg before it is consumed. 相似文献
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1000.
JinguangXu ZhijianTian JunweiWang YunpengXu ZhushengXu LiwuLin 《天然气化学杂志》2003,12(2):105-112
Conventional oven drying (COD) and supercritical drying (SCD) methods were applied to the preparation of Mn-substituted hexaaluminate (BaMnA111O19-α) catalysts. The effect of drying methods on phase composition, specific surface area, pore structure, reduction behavior of Mn^3 ions, and combus-tion activity of the samples was investigated. The homogenous mixing of the components in the sol-gel process could be maintained by SCD, and the hexaaluminate phase was almost the only phase of the resulting materials after calcination. H2-TPR revealed that the Mn^3 ions in the sample obtained by SCD were easier to be reduced than that by COD. Moreover, the samples obtained by SCD have higher surface area, narrower pore size distribution, and higher combustion activity than those obtained by COD. 相似文献