Generation of Hermite-Gaussian modes and vortex arrays based on two-dimensional gain distribution controlled microchip laser

We have demonstrated high-order Hermite-Gaussian (HG) mode generation based on 2D gain distribution control edge-pumped, composite all-ceramic Yb:YAG/YAG microchip lasers using a V-type cavity. Several hundred milliwatts to several watts HG(mn) modes are achieved. We also generated different kinds of vortex arrays directly from the oscillator with the same power level. In addition, a more than 7 W doughnut-shape mode can be generated in the same cavity.     

Preparation of nano-sized Al2O3–2SiO2 powder by sol–gel plus azeotropic distillation method

Nano-sized amorphous Al₂O₃–2SiO₂ powder was prepared by a sol–gel method coupled with azeotropic distillation. The structure of the powder was investigated by DTS, BET, TEM, FT-IR, TG-DTA and XRD, showing that n-butanol azeotropic distillation could effectively remove water from the aluminosilicate gels and prevent the formation of hard agglomerates in the drying process. The average particle diameter of the powder was about 70 nm. The largest BET specific surface area of the powder was 669 m²/g. To examine the alkali-activation reactivity of the powder, alkali-activation tests were performed with the powder reacting with sodium silicate solution. The synthetic powder was found to be highly reactive.     

Hendecanuclear [Cu_6Gd_5] magnetic cooler with high molecular symmetry of D_(3h)

A new family of isostructural 3 d-4 f polymetallic complexes,formulated as [Cu_6Ln_5(μ_3OH)_9(C_4H_8O_2N)_6(C_5H_4ON)_6(H_2O)_9]·(ClO_4)_6·(H_2O)_(22)(Ln=Pr,1;Nd,2;Sm,3;Eu,4;Gd,5),was successfully isolated through the simple hydrolysis reaction of 2-aminoisobutyric acid,2-hydroxypyridine,Cu(CH_3COO)_2·H_2O,and Ln(ClO_4)_3·6 H_2O.Notably,the [Cu_6Ln_5] clusters with high molecular symmetry ofD_(3 h) are rare examples of2-aminoisobutyric acid-based 3 d-4 f clusters.The successful theoretical modeling of 5 yielded that the Gd-Gd exchange is of order 0.2 K,whereas the Gd-Cu exchange is an order of magnitude larger.Magnetization data collected for comp lex 5 yield a magnetic entropy change(-ΔSm) of 19.6 J kg ~1 K~11 at 3 K and 7 T,which may be attributed to the weak magnetic interactions between the component metal ions.     

一类3维反转系统中的异维环分支

研究了一类3维反转系统中包含2个鞍点的对称异维环分支问题, 且仅限于研究系统的线性对合R的不变集维数为1的情形. 给出了R-对称异宿环与R-对称周期轨线存在和共存的条件, 同时也得到了R-对称的重周期轨线存在性. 其 次, 给出了异宿环、 同宿轨线、 重同宿轨线和单参数族周期轨线的存在性、 唯一性和共存性等结论, 并且发现不可数无穷条周期轨线聚集在某一同宿轨线的小邻域内. 最后给出了相应的分支图.     

Effects of global orbital cutoff value and numerical basis set size on accuracies of theoretical atomization energies

Numerical basis sets are known for their rapid convergence in density functional theory calculations. The selections of global orbital cutoff values and numerical basis set sizes are important to the computational accuracies and efficiencies. In this study, the effects of global orbital cutoff values and numerical basis set sizes on the theoretical atomization energies (D ₀) were investigated using density functional theory with the generalized gradient approximation. Our results on the total energies of seven atoms and D ₀ of a set of 44 molecules demonstrate that the numerical orbital cutoff value should be larger than 6.5 Å to get the converged energetic properties. Through comparing the D ₀ of these 44 molecules obtained by using four kinds of different numerical basis sets, DN, DND, DNP, and TNP, it demonstrates that the DNP basis set is good enough to predict accurate D ₀ with affordable computational cost.     

Refractive index sensors based on Ag-metalized nanolayer in microstructured optical fibers

We propose refractive index sensors based on Ag-metalized nanolayer in microstructured optical fibers. The surface plasmon resonance modes and the sensing properties are theoretically analyzed using finite element method (FEM). In the calculation, Drude–Lorentz model is used to describe the Metal Dielectric constant. The calculation results show that the sensitivity of Ag-metalized SPR sensor can reach 1500 nm/RIU corresponding to a resolution of 6.67 × 10^?5 RIU. Comparing with conventional detecting material-Au under the same structure, the sensitivity and 3 dB bandwidth of our device are better.     

Smart supramolecular vesicles based on glutathione-reactive pillar[6]arene and acid-labile prodrug: Dual drug loading and sequential release

Glutathione thiol-reactive pillar[6]arene (TWP6) is designed and synthesized as the first example of reducing agent-reactive host molecule. TWP6 shows high affinity binding towards suitable anti-tumor drugs and guests. Doxorubicin-based acid-labile prodrugs and TWP6 are used to construct supramolecular vesicles, which are also loaded with camptothecin. The supramolecular vesicles loaded with two drugs demonstrate glutathione- and acid-responsive drug release as well as sequential release to both stimuli types. Supramolecular vesicles show combination therapeutic effect towards tumor cells in vitro.