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51.
The title compound 4-chloro-2-(morpholine-4-carbonyl)phenyl-4'-methoxybenzoate(C19H18ClNO5, Mr = 375.79), a 5-chlorosalicylic acid derivative incorporating morpholine moiety, was conveniently synthesized through two steps and crystallized in the monoclinic space group P21/c with a = 7.8501(10), b = 9.3149(12), c = 25.133(3), V = 1836.2(4)3, Z = 4, Dc = 1.359 Mg/m3, λ = 0.71073, μ(MoKα) = 0.237 mm-1, F(000) = 784, R = 0.0447 and wR = 0.1227 for 3982 independent reflections with I 2σ(I). The dihedral angles formed between 4-methoxybenzene and 5-chlorobenzene rings, the 5-chlorobenzene and morpholine, and 4-methoxybenzene and morpholine rings are 82.55(3), 72.56(5) and 47.68(0)° by X-ray analysis, respectively. Bioassay shows that the title compound has a good molluscidal effect. 相似文献
52.
《Tetrahedron: Asymmetry》2014,25(13-14):1026-1030
The synthesis of sitagliptin phosphate 1, a novel DPP-IV inhibitor for the treatment of type 2 diabetes mellitus has been accomplished starting from the chiral synthon (1,4-bis[(R)-1-phenylethyl]piperazine-2,5-dione) 2, involving highly stereocontrolled (>98%) alkylation as a key step, in a good overall yield of 50% over six steps. 相似文献
53.
54.
By introducing an auxiliary ordinary differential equation and solving it by means of the method of separation of variables, many new explicit exact solutions to the Born–Infeld equation are found in a concise manner.
PACS: 02.30.Jr; 03.40.Kf 相似文献
55.
利用光化学还原法制备载铂Sr(Zr1-xYx)O3-δ-TiO2 (Pt-SZYT)异质结光催化剂, 采用XRD, SEM, UV-Vis, PL对催化剂的形貌及性能进行表征. 以工业有机污染物草酸为电子给体, 模拟太阳光下光催化产氢为探针, 评价了催化剂的活性. 研究了载铂量、草酸浓度对催化剂产氢活性的影响, 并探讨了Pt-SZYT催化剂产氢活性与光致发光(PL)性能的关系, 以及催化剂的连续使用效果. 结果表明: 模拟太阳光条件下, Pt-SZYT催化剂具有良好稳定的光催化产氢活性, 催化剂的最佳载铂量为0.90 wt%. PL分析表明Pt-SZYT的光催化产氢活性越高, 其荧光强度越弱. 草酸50 mmol•L-1, 催化剂用量1.0 g•L-1时, 催化剂(w=0.90%) Pt-SZYT-70的平均产氢速率为1.68 mmol•h-1. 相似文献
56.
对2015-2020年SOLO分类理论在中学化学教育中应用研究的62篇文献进行分析,总结出SOLO分类理论应用研究的5个方面:(1)指导习题编制与评分标准确立;(2)分析中、高考试题;(3)指导教学实践;(4)指导学习心理实证研究;(5)指导教学评价。并通过对其在初高中化学教育中应用研究的情况对比,总结出高中教师的成功经验可为初中教师的相关研究提供参考,并对中学教师运用SOLO分类理论解决教学中的问题提出建议。 相似文献
57.
In this paper, a kind of Liénard equation with multiple deviating arguments of the form $$x''(t)+f(x(t))x'(t)+\sum_{k=1}^{n}g_{k}(t,x(t-\tau_{k}(t)))=p(t)$$ is considered. By using coincidence degree theory, some criteria are obtained to guarantee the existence and uniqueness of periodic solutions of this equation. The obtained results are also valid and new for the problem discussed in the previous literature. 相似文献
58.
Qin-Qin Wu Lan Xu Qing-Shou Tan Lin-Ling Yan 《International Journal of Theoretical Physics》2012,51(5):1482-1490
We study the multi-qubit entanglement transfer in a hybrid circuit quantum electrodynamics system, where the memory and operation
registers are, respectively, implemented using nitrogen-vacancy centers in diamond and superconducting charge qubits, because
of their respective good coherence and controllability. We show that, with some local operations, both the Bell states and
multi-qubit W states can be transferred perfectly in the non-dissipative case. In addition, we also consider the influence
of the decoherence on the state transfer. It is found that a high-fidelity state transfer can be achieved only when the decoherence
rates are much smaller than the coupling strength between the qubits. 相似文献
59.
Controllable cross-Kerr interaction between microwave photons in circuit quantum electrodynamics 下载免费PDF全文
We propose a scheme to enable a controllable cross-Kerr interaction between microwave photons in a circuit quantum electrodynamics(QED) system.In this scheme we use two transmission-line resonators(TLRs) and one superconducting quantum interference device(SQUID) type charge qubit,which acts as an artificial atom.It is shown that in the dispersive regime of the circuit-QED system,a controllable cross-Kerr interaction can be obtained by properly preparing the initial state of the qubit,and a large cross-phase shift between two microwave fields in the two TLRs can then be reached.Based on this cross-Kerr interaction,we show how to create a macroscopic entangled state between the two TLRs. 相似文献
60.
Jianhui Yan Qiang Liu Luxiong Guan Feng Liang Haojie Gu 《Frontiers of Chemistry in China》2009,4(2):121-126
The Pt-Sr(Zr1 − x
Y
x
)O3 − δ
-TiO2(Pt-SZYT) heterojunction photocatalysts were prepared by a photodeposition method. The composite particles were characterized
by XRD, SEM, UV-Vis DRS, and PL techniques. Photocatalytic hydrogen generation in H2C2O4 aqueous solution under the irradiation of simulated sunlight was used as a probe reaction to evaluate the photocatalytic
activity of the photocatalysts. The effects of the content of Pt loading and the concentration of oxalic acid on the photocatalytic
activity of the catalyst were discussed. The continuous photocatalytic activity of the Pt-SZYT and the relationship between
PL intensity and hydrogen generation were also discussed. The results show that Pt-SZYT catalysts had high photocatalytic
activity of hydrogen generation. The content of Pt loading and the concentration of oxalic acid have important influence on
the photocatalytic hydrogen generation. The optimal loading content of platinum was 0.90 mass%. Under this condition, the
average rate of photocatalytic hydrogen generation was 1.68 mmol·h−1 when the concentration of oxalic acid was 50 mmol·L−1. The higher the photocatalytic activity, the weaker the PL intensity, which was demonstrated by the analysis of PL spectra.
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Translated from Acta Chimica Sinica, 2008, 61 (in Chinese) 相似文献