D-Proline capped gold nanoclusters for turn-on detection of serum Raltitrexed

Using D-proline (D-Pro) as the reducing agent and capper, D-Pro@AuNCs was rapidly constructed. Its fluorescence could be quenched by AuNPs. Due to the electrostatic interaction between anticancer drug Raltitrexed (RTX) and AuNPs induced fluorescence "turn-on" principle, the resultant fluorescent probe exhibited good selectivity and sensitivity for detecting RTX in rat serums.     

Entanglement of a photon and a collective atomic excitation

We describe a new experimental approach to probabilistic atom-photon (signal) entanglement. Two qubit states are encoded as orthogonal collective spin excitations of an unpolarized atomic ensemble. After a programmable delay, the atomic excitation is converted into a photon (idler). Polarization states of both the signal and the idler are recorded and are found to be in violation of the Bell inequality. Atomic coherence times exceeding several microseconds are achieved by switching off all the trapping fields--including the quadrupole magnetic field of the magneto-optical trap--and zeroing out the residual ambient magnetic field.     

Study of nanocrystalline diamond film growth in rf hybrid laser deposition systems in O2, H2 and H2+Ar ambients

Pulsed laser deposition (PLD) and hybrid pulsed laser deposition (HPLD) systems were used for nanocrystalline diamond (NCD) film growth on Si(100) and sapphire(0001) substrates. The PLD system was based on a KrF excimer laser (=248 nm,20 ns), which ablated a graphite target in pure oxygen or hydrogen ambient. The HPLD system was based on a combination of PLD and additional capacitively coupled radio-frequency discharges (13.56 MHz) in argon–hydrogen ambient. Radio-frequency power was applied to two plane parallel electrodes or directly to the substrate holder. The working atmosphere pressure was varied from 1 Pa to 220 Pa and the substrate temperature was varied from 20 °C to 660 °C. X-ray diffraction analysis, Raman spectroscopy and a profilometer were used to study the deposited film properties. A band around 1180 cm^-1, which can be attributed to NCD, occurred in the Raman spectra. A characteristic diamond peak at 1332 cm^-1 was not observed. Films prepared by HPLD showed better compositional homogeneity (from Raman analysis) than films created by PLD. PACS 52.80.Pi; 81.07.Bc; 81.15.Fg     

Spontaneous transverse patterns in a microchip laser with a frequency-degenerate resonator

We experimentally observe the formation of high-order transverse patterns in a microchip laser with a high degree of frequency degeneracy. With a doughnut pump profile the spontaneous transverse patterns are well localized in the Lissajous trajectories. The observed transverse patterns are reconstructed with a high degree of accuracy by use of the coherent state of quantum theory. The accurate reconstruction suggests that laser resonators can be designed to obtain a more thorough understanding of the quantum-classical connection.     

Novel chiral imidazole cyclophane receptors: synthesis and enantioselective recognition for amino acid derivatives

Novel chiral imidazole cyclophane receptors were synthesized by highly selective N-alkylation of the imadazolyl 1N-position of the bridged histidine diester 2 with the dibromide in the presence of NaH; these receptors exhibit good chiral recognition toward the enantiomers of L- and D-amino acid derivatives (up to KD/KL = 3.52, delta delta G0 = -3.11 kJ mol-1) in CHCl3 at 25.0 degrees C.     

Connecting Lemmas

Like the closing lemma, the connecting lemma is of fundamental importance in dynamical systems. Hayashi recently proved the connecting lemma for stable and unstable manifolds of a hyperbolic invariant set. In this paper, we prove several very general connecting lemmas. We simplify Hayashi's proof and extend the results to more general cases.

     

Efficient high-power diode-end-pumped TEM(00) Nd:YVO(4) laser with a planar cavity

We demonstrate a compact and efficient diode-end-pumped TEM>(00) laser with output power of 30 W for 48 W of incident pump power by use of two coated Nd:YVO> (4) crystals to form a thermally stabilized flat-flat cavity. In Q -switched operation 25 W of average power at a pulse-repetition rate of 100 kHz and ~0.9-mJ pulse energy at a pulse-repetition rate of 10 kHz were produced.     

干涉理论对bottle beam的描述

对轴棱锥产生的贝塞尔光聚焦特性的描述，我们提出一种有别于惠更斯-菲涅耳衍射积分理论的解析表达.这种解析表达基于干涉理论的基础，它能够模拟计算出聚焦透镜置于最大准直距离之外以及在聚焦透镜焦平面以后的光束行为，能够更好地描述bottle beam的形成过程，这些结果用衍射积分理论是得不到的.我们还得到了与Wei用几何光学分析所得出的当z_0max将产生hollow beam的不同结论.所有理论计算结果都得到实验的有力验证. 关键词： bottle beam 贝塞尔光 轴棱锥 光镊     

向列相液晶中强非局域空间光孤子传输的理论研究

对向列相液晶中非局域空间孤子的传输进行了理论研究.基于非线性液晶孤子传输方程，采用Gauss形式的试探解，不仅得到了空间孤子的解析解,而且还在临界功率附近得到了呼吸子的解析解.通过数值模拟证明我们的结果比Conti和Assanto等人的结果更合理.同时，对液晶中的非局域孤子模型和Snyder等提出的强非局域孤子模型进行了全面的比较. 关键词： 向列相液晶 空间孤子 非局域非线性 呼吸子