Efficient stereocontrolled synthesis of sitagliptin phosphate

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.     

传统大学物理实验的探究式教学

从探究式教学的基本特征出发,通过典型的传统大学物理实验活动的教学设计,在大学物理实验教学中培养学生进行科学探究的能力和对科学探究的理解力,以进一步推动大学物理实验教学改革.     

New Explicit Exact Solutions of the Born–Infeld Equation

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     

Some Features of Hyperspherical Functins

ＳｏｍｅＦｅａｔｕｒｅｓｏｆＨｙｐｅｒｓｐｈｅｒｉｃａｌＦｕｎｃｔｉｎｓ￥ＷａｎｇＡｎｂｉｎ（王安斌）（ＹｕｅｙａｎｇＴｅａｃｈｅｒ＇ｓＣｏｌｌｅｇｅ４１４０００）Ａｂｓｔｒａｃｔ：ＬｅｔＰ（ａ，ａ）ｎ（ｚ）ｂｅｎ－ｄｅｇｒｅｅｈｙｐｅｒｓｐｈｅｒｉ...     

载铂Sr(Zr1－xYx)O3－δ-TiO2异质结光催化剂模拟太阳光催化产氢

利用光化学还原法制备载铂Sr(Zr_1－xY_x)O_3－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.     

SOLO分类理论在初高中化学教育中的应用研究对比*

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。     

2-氨基-4,5-二取代烃嘧啶类衍生物的新合成方法

研究了2-氨基-4,5-二烃基取代嘧啶类衍生物的一个新的简易合成方法,该方法以简单且廉价的4个芳香醛和3个脂肪醛为原料,经过四步反应得到12个2-氨基-4,5-二烃基取代嘧啶类化合物,总收率在40%～70%,经氢核磁共振(1H NMR)、碳核磁共振(13C NMR)和高效液质联用(LC-MS)对其目标产物进行表征.     

Existence and uniqueness of periodic solutions for?a?kind of?Liénard equation with multiple deviating arguments

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.     

Multipartite entanglement transfer in a hybrid circuit-QED system

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.     

Controllable cross-Kerr interaction between microwave photons in circuit quantum electrodynamics

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.