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A rapid method had been used for comparative study on Artemisia halodendron Turcz. and its two related plants by gas phase-mass spectrometry (GC-MS). The comparison of the volatile oils obtained in three plants by GC-MS were similar in 20 compositions. However, n-Hexadecanoic acid (10.40%), Biphenyl (7.867%) and 9,12-Octadecadienoic acid (7.25%) were the predominant in the volatile oils of A. halodendron Turcz., whereas these constituents did not exist in the other two plants. And the study investigated the effect of three plants against CCl4-induced hepatotoxicity in mice. 70% ethanol extracts of A. halodendron Turcz. showed weaker protective effect than the other two plants. It suggested that they provide a basis for the identification of the A. halodendron Turcz. from the other two plants and the ethanol extract from three plants exerted a protecting effect against hepatotoxicity. 相似文献
155.
Hyper-parallel quantum information processing is a promising and beneficial research field. Herein, a method to implement a hyper-parallel controlled-phase-flip (hyper-CPF) gate for frequency-, spatial-, and time-bin-encoded qubits by coupling flying photons to trapped nitrogen vacancy (NV) defect centers is presented. The scheme, which differs from their conventional parallel counterparts, is specifically advantageous in decreasing against the dissipate noise, increasing the quantum channel capacity, and reducing the quantum resource overhead. The gate qubits with frequency, spatial, and time-bin degrees of freedom (DOF) are immune to quantum decoherence in optical fibers, whereas the polarization photons are easily disturbed by the ambient noise. 相似文献
156.
Dong Liangwei Qi Wei Peng Ping Wang Linxue Zhou Hui Huang Changming 《Nonlinear dynamics》2020,102(1):303-310
Nonlinear Dynamics - We address the nonlinear dynamics of binary Bose-Einstein condensates with mutually symmetric spinor components trapped in an optical lattice. The interaction between the... 相似文献
157.
Alkynes cycloaddition reactions are powerful tools for constructing cyclic molecules with optimal atom efficiency, but these reactions cannot proceed at ambient temperature without transition-metal catalysts. In this work, a heterobimetallic complex featuring an Nb–Fe triple bond, Nb(iPrNPMe2)3Fe–PMe3, has been evaluated as the potential catalyst for acetylene cycloaddition, using density functional theory. The calculated results show that the singlet-state (i.e. ground-state) Nb(iPrNPMe2)3Fe–PMe3 can be applied to benzene synthesis, but is not suitable for cyclobutadiene. Benzene can be obtained easily at room temperature and is the unique product on the singlet potential surface. The irradiation of infrared-red light can drive the excitation of singlet Nb(iPrNPMe2)3Fe–PMe3 to its triplet state. Both benzene and cyclobutadiene can be formed on the triplet reaction potential surface due to their low energy barriers. Therefore, Nb(iPrNPMe2)3Fe–PMe3 is a potential high reactivity heterobimetallic catalyst for the cyclotrimerization of alkynes. In the reaction process, the catalytic active site of Nb(iPrNPMe2)3Fe–PMe3 moves from niobium to iron. 相似文献
158.
Ziritaxestat is a first-in-class autotoxin inhibitor. The purpose of this study was to develop a liquid chromatography/electrospray ionization tandem mass spectrometric (LC–MS/MS) method for the determination of ziritaxestat in rat plasma. The plasma sample was deproteinated using acetonitrile and then separated on an Acquity BEH C18 column with water containing 0.1% formic acid and acetonitrile as mobile phase, which was delivered at 0.4 ml/min. Ziritaxestat and the internal standard (crizotinib) were quantitatively monitored with precursor-to-product transitions of m/z 589.3 > 262.2 and m/z 450.1 > 260.2, respectively. The total running time was 2.5 min. The method showed excellent linearity over the concentration range 0.5–2000 ng/ml, with correlation coefficient >0.9987. The extraction recovery was >82.09% and the matrix effect was not significant. Inter- and intra-day precisions (RSD) were <11.20% and accuracies were in the range of −8.50–7.45%. Ziritaxestat was demonstrated to be stable in rat plasma under the tested conditions. The validated LC–MS/MS method was successfully applied to study the pharmacokinetic profiles of ziritaxestat in rat plasma after intravenous and oral administration. Pharmacokinetic results demonstrated that ziritaxestat displayed a short half-life (~3 h) and low bioavailability (20.52%). 相似文献
159.
Several phenoxy-imine ligands bearing o-trityl group in phenoxy moiety RN=CHArOH (Ar = C6H2(CPh3)tBu, R = 2,6-Me2C6H3 ( L 1 H ); 2,6-iPr2C6H3 ( L 2 H ); 3,5-(CF3)2C6H3 ( L 3 H ); 3,5-(OMe)2C6H3 ( L 4 H ); CHPh2 ( L 5 H ); CPh3 ( L 6 H )) were synthesized and characterized by1H NMR and 13C NMR spectroscopy. The vanadium complexes based on these ligands LVCl2(THF)2 ( 1–6 ) were synthesized via conventional transmetalation reaction in moderate to high yields. Complexes 1–6 were fully characterized by FT-IR, elemental analyses and the molecular structures of 1 , 2 ·H2O, (2 ·H2O ) 2 (μ-Cl) 2 , 4 , and 5 were confirmed by X-ray crystallographic analysis in which the six-coordinated vanadium centers are in a typical octahedral geometry. Upon activation with Et2AlCl in toluene, complexes 1–6 showed high activities in ethylene polymerization affording polymers with moderate molecular weight (5.9–11.8 × 104 Da). Moreover, in hexane or CH2Cl2, 1–6 /Et2AlCl exhibited enhanced activities. When activated with MAO or MMAO in toluene, these complexes showed relatively low activities but afforded polymers with ultra-high molecular weight (up to 3.30 × 106 Da). 1–6 /Et2AlCl also showed high activities in ethylene/1-hexene copolymerization at room temperature giving moderate molecular-weight polymers (6.5–11.4 × 104 Da) with co-monomer incorporation being of 6.0 ~ 7.8%. 相似文献
160.
Hejia Hu Linlin Wu Mei Li Cun Xue Guangcheng Wang Siying Chen Yong Huang Lin Zheng Aimin Wang Yueting Li Zipeng Gong 《Biomedical chromatography : BMC》2020,34(1):e4714
Eucommia ulmoides Oliv. (E. ulmoides) is a valuable and nourishing medicinal herb in China that has been used in the treatment of hypertension. Given the fact that most traditional Chinese medicine is mainly used to treat disease, investigating the pharmacokinetics of traditional Chinese medicines in the pathological state is more useful than that in the normal state. However, the differences in the absorption kinetics of active ingredients of E. ulmoides extract between pathological and physiological conditions have not been reported. Therefore, in this study, the rat intestinal in situ circulatory perfusion model was used to investigate the differences in absorption kinetics of seven active ingredients of E. ulmoides extract in normal and spontaneously hypertensive rats, namely, genipinic acid, protocatechuic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, (+)-pinoresinol di-O-β-D -glucopyranoside and (+)-pinoresinol 4′-O-β-D -glucopyranoside. Our results indicate that the pathological state of spontaneous hypertension may change the absorption of active components of E. ulmoides extracts, and these findings may provide a reference for improving the rational use of E. ulmoides in the clinic. 相似文献