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101.
本文报道以青蒿酸(2)为原料合成了一些含羟基的青蒿倍半萜内酯差向异构体9与10、11与12、13与14。其中9已从青蒿中分离到。 相似文献
102.
THz spectroscopic investigation of 2,4-dinitrotoluene 总被引:5,自引:0,他引:5
Yunqing Chen Haibo Liu Yanqing Deng Dunja Schauki Michael J. Fitch Robert Osiander Caroline Dodson James B. Spicer Michael Shur X.-C. Zhang 《Chemical physics letters》2004,400(4-6):357-361
We have investigated the terahertz (THz) spectrum of 2,4-DNT by using Fourier transform infrared spectroscopy in the 0.2–19.5 THz region. We also examined low-frequency intermolecular or phonon modes between 0.2 and 1.8 THz via THz time-domain spectroscopy. The extracted absorption coefficient and refractive index of an intermolecular band at 1.08 THz are 110 cm−1 and 1.67, respectively. Density functional theory (DFT) was applied to obtain structure and vibrational frequencies of 2,4-DNT. The calculated results are in agreement with the experimental data. Observed vibrational frequencies have been interpreted using DFT. Two intermolecular or phonon modes were identified at 1.08 and 2.52 THz. 相似文献
103.
A capillary electrophoresis--inductively coupled plasma atomic-emission spectrometry (CE-ICP-AES) system using a polytetrafluoroethylene (PTFE) capillary has been developed. The CE-ICP interface was a modified concentric nebulizer. The PTFE capillary (50 microm internal diameter) was used as the central capillary of the nebulizer. Using the PTFE capillaries, the solution flow rate induced by the carrier gas flow was smaller than that of glass capillary. Solution flow was mainly induced by the CE electric field. Baseline separation of Ba2+/Mg2+ ion pair using simple buffer solution of 0.014 M sodium acetate was reported. Separation and correlation of metal species in metallothioneins (MT-1 and MT-2 in MT) of rabbit liver using the CE-ICP system were also discussed. 相似文献
104.
105.
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
106.
107.
Yi Ming Liu Sui Ping Deng Hui Zheng Jian Ming Ouyang 《中国化学快报》2007,18(3):345-348
The ring patterns of calcium oxalate crystals were induced by domains in Langmuir-Blodgett (LB) films of dipalmitoylpho- sphatidylcboline (DPPC). The result was explained by the defects at the ring boundaries of liquid condensed (LC) and liquid expanded (LE) phases of LB film. These boundaries could provide less free energy and much more nucleating sites for COM crystals. 相似文献
108.
2-(Chloromethyl)furan as an electrophile reacted with lithium trialkylalkyllylbo-rates,followcl by the oxidation with H_2O_2 under basic condition to afford 2-furfurylketonesin good yields.This provides a new method for the preparation of 2-furfurylkctoncs. 相似文献
109.
110.
锂辉石—石灰石烧结中煤粉代替重油作燃料的研究和实践 总被引:1,自引:0,他引:1
目前世界锂工业原料以锂辉石为主。我国锂辉石储量居世界首位,主要分布于新疆、四川、湖南等地,其中又以四川的储量占全国第一。锂的主要基础化合物LiOHH2O系用锂辉石-石灰石烧结法而得,烧结燃料是影响LiOHH2O产品价格的重要因素之一。过去国内外均采用... 相似文献