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961.
Shi-Yu Wang Wen-Min Wang Ying-Ping Quan Hong-Ling Gao 《Journal of Coordination Chemistry》2016,69(4):594-603
Four lanthanide-nitronyl nitroxide radical complexes, [Ln(hfac)3(NIT-3Methien)2] (Ln = Pr (1), Tb (2), Dy (3), Ho (4); hfac = hexafluoroacetylacetonate; NIT-3Methien = 2-(3-methylthiophene)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), have been synthesized, and structurally and magnetically characterized. Single-crystal X-ray diffraction shows that 1–4 have similar mononuclear tri-spin structures in which central Ln(III) ions are eight coordinate by two NIT-3Methien radicals and three hfac coligands. The magnetic studies indicate that there are antiferromagnetic interactions between Ln(III) ions and radicals in 1, 2, and 4, while ferromagnetic interactions are present in 3. The luminescence properties of 2 and 3 were studied. 相似文献
962.
Human immunodeficiency virus (HIV) diagnostics are urgently needed in resource-scarce settings. Monitoring of HIV-infected patients requires accurate counting of CD4+ T lymphocytes. However, the current methods for enumeration of CD4+ T lymphocytes are of high cost, technically complex and time-consuming. In this paper, we developed a simple, rapid and inexpensive one-step immunomagnetic method for separating and counting CD4+ T lymphocytes on microfluidic devices with enlarged reaction chambers. CD4+ T lymphocytes were successfully separated and captured from the cell suspension obtained from mouse thymus. CD4 counts were determined under an optical microscope in a rapid and simple format. In order to acquire the maximum efficiency of cell capture, relative parameters were investigated, including section area of the reaction chamber and injection flow rate of the cell suspension. The enlarged reaction chamber with two symmetrical cone-shaped ends was helpful for cell capture, and the maximum capability of captured CD4+ T lymphocytes was about 700 cells μL−1. Our investigations avoided the complex sample pre-treatment, and the entire analysis time was significantly reduced to 15 min. This CD4 counting microdevice had the potential to reduce the cost for HIV diagnosis in resource-limited settings. 相似文献
963.
964.
965.
Liu H Zhang X Gao H Wang N Jin S Cai B Yao X Cai G 《Chemical & pharmaceutical bulletin》2005,53(10):1310-1313
Phytochemical study of the ethanol extract of the seeds of Aesculus assamica led to the isolation of two new triterpenoid saponins. The structure of the new compounds were elucidated on the basis of spectral data to be 28-O-acetyl-21-O-(4-O-angeloyl)-6-deoxy-beta-glucopyranosyl-3-O-[beta-glucopyranosyl(1-2)-O-[beta-glucopyranosyl(1-4)]-beta-glucuronopyranosyl]protoaescigenin (1), and 21-O-(4-O-angeloyl)-6-deoxy-beta-glucopyranosyl-3-O-[beta-glucopyranosyl(1-2)-O-[beta-glucopyranosyl(1-4)]-beta-glucuronopyranosyl]protoaescigenin (2). Their in vitro bioactivity against plant pathogenic fungus Pyricularia oryzae and cytotoxicity against K562 and HCT-15 cell lines were evaluated. 相似文献
966.
In this article, we study the kth upper and lower bases of primitive nonpowerful minimally strong signed digraphs. A bound on the kth upper bases for primitive nonpowerful minimally strong signed digraphs is obtained, and the equality case of the bound is characterized. For the kth lower bases, we obtain some bounds. For some cases, the bounds are best possible and the extremal signed digraphs are characterized. We also show that there exist ‘gaps’ in both the kth upper base set and the kth lower base set of primitive nonpowerful minimally strong signed digraphs. 相似文献
967.
Gao LH Wang KZ Cai L Zhang HX Jin LP Huang CH Gao HJ 《The journal of physical chemistry. B》2006,110(14):7402-7408
A surfactant ion-pair complex, [Ru(bpy)(2)L][Eu(NTA)(4)](2) (in which L = 1-docosyl-2-(2- pyridyl)benzimidazole, bpy = 2,2'-bipyridine, and NTA = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedionato) has been synthesized. The surface pressure-area isotherm measurements show that the complex forms a stable Langmuir film at the air-water interface without adding any electrolytes into the subphase. The monolayers formed at the surface pressures of 5 mN m(-1) and 20 mN m(-1), have been successfully transferred onto glass and quartz substrates with the transfer ratios close to unity. The Langmuir-Blodgett films were studied by UV-visible, infrared, and emission spectroscopies, atomic force microscopy, and cyclic voltammetry. The optical, redox, and morphology properties of the LB films were found to be significantly affected by the target surface pressures used for the film depositions. 相似文献
968.
具有Dawson结构的钼钒磷杂多酸氧化还原性质的研究 总被引:5,自引:1,他引:5
通过SnCl2电位滴定、极谱和循环伏安方法,详细研究了2:18系列钼钒磷杂多酸H(6+n)[P2Mo13-nVnO62]·xH2O(n=1~3)和H4+n[P2Mo18-nVnO62H2]·xH2O(n=4,5)在溶液中的氧化还原性质,证实它们的还原为三步分别加合n,2,2个电子,同时加合n,2,2个质子的过程,总结了循环伏安峰电位与pH的关系,提出了还原机理。 相似文献
969.
C. Gao J. Yang X. J. Meng T. Lin J. H. Ma J. L. Sun J. H. Chu 《Applied Physics A: Materials Science & Processing》2011,104(1):123-128
The dielectric properties of fresh and aged Ba(Zr0.25Ti0.75)O3 thin films have been investigated. It is found that the aged sample shows a significant decrease in the dielectric constant
compared to the fresh one. Furthermore, the aged sample also exhibits abnormal double-peaks-shape butterfly C–V characteristics, which indicates the defect-dipole stabilized domain and/or domain-wall motions. Meanwhile, we found that
double-peaks-shape butterfly C–V characteristics become weak and even disappear with increasing of applied electric field and temperature. The present results
are discussed in light of the symmetry-conforming principle of point defects. 相似文献
970.
GAO Lei ZHANG Jing HE Chang SHEN SuLing ZHANG Yi LIU HongTao SUN QingJiang LI YongFang 《中国科学:化学(英文版)》2013,56(7):997-1003
A new star-shaped donor-acceptor molecule has been synthesized for application as the donor material in solution-processed bulk-heterojunction organic solar cells (OSCs). The molecule consists of a triphenylamine (TPA) unit as the core and a donor unit with three arms containing benzo[1,2,5]thiadiazole (BT) acceptor units and 5,5’’-dihexyl-2,2′:3′,2″-terthiophene (tTh) end groups. The molecule, denoted S(TPA-BT-tTh), exhibits a broad absorption band in the wavelength range 300-650 nm and high hole mobility of 1.1×10 -4 cm2 V -1 s 1 . An OSC device based on S(TPA-BT-tTh) as donor and [6,6]-phenyl C71 -butyric acid methyl ester (PC 70 BM) as the acceptor (1:3, w/w) exhibited a power conversion efficiency of 2.28% with a short circuit current density of 6.39 mA/cm2 under illumination of AM.1.5, 100 mW/cm2 . 相似文献