다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

The primary goal of this review is to present a clear chemical perspective of borates in order to stimulate and facilitate the discovery of new borate-based optical materials. These materials, whic...

Borates: A Rich Source for Optical Materials.

Discovery of new efficient nonlinear optical (NLO) materials with large second-order nonlinearity for short-wave UV spectral region (λ PM ≤ 266 nm, PM = phase-matching) is still very challenging. Herein, by applying tetrahedra substitution strategy based on Sr 2 Be 2 B 2 O 7 (SBBO), a new beryllium-free borate CaZn 2 (BO 3 ) 2 with double-layered configuration was rationally designed, which not only preserves the structural merits but also eliminates the limitations of SBBO crystal. CaZn 2 (BO 3 ) 2 shows a large PM second harmonic generation (SHG) reponse of 3.8×KDP, which is 38 times higher than its barium analogue. This enhancement originates from the 1 [Zn 2 O 6 ] ∞ polar chains with large net dipole moment and [BO 3 ] units with high NLO active density. Our findings show the great significance of [ZnO 4 ] tetrahedra introduced strategy to design beryllium-free SBBO-type NLO crystals and also verify the feasibility of using simple non-isomorphic substitution to induce giant second-order nonlinearity enhancement.

Strong Nonlinearity Induced by Coaxial Alignment of Polar Chain and Dense [BO3] Units in CaZn2(BO3)2.

Potential optical functional crystals with large birefringence: Recent advances and future prospects

A novel Z-scheme photocatalyst Bi-Bi2O3/KTa0.5Nb0.5O3 (KTN) composite was prepared by a simple solvothermal method. Compared with KTN, Bi/KTN, and Bi2O3/KTN, Bi-Bi2O3/KTN ternary composite catalyst presented much better photocatalytic ammonia-synthesis efficiency....

A novel Z-scheme Bi-Bi2O3/KTa0.5Nb0.5O3 heterojunction for efficient photocatalytic conversion of N2 to NH3

A colorless crystal of Ba2Mg(BO3)2 about 37 × 25 × 17 mm3 has been grown successfully by the Kyropoulos method. Thermal analyses results show that Ba2Mg(BO3)2 melts congruently. The phase purity of the raw materials and the grown crystals were confirmed by powder X-ray diffraction. Ba2Mg(BO3)2 exhibits a low UV cutoff of 187 nm and high transmittance below 3000 nm. The refractive indices of the crystal have been measured and the the least-squares fitting method was used to obtain the Sellmeier dispersion equations. The results indicate that Ba2Mg(BO3)2 is a potential birefringence crystal with large birefringence of 0.10422 at 546 nm.

Growth and optical properties of a promising Deep-ultraviolet birefringent crystal Ba2Mg(BO3)2

We present the continuous-wave (CW) and passively Q-switched laser operation of disordered Nd:ABC3O7 crystals including Nd:SrLaGa3O7, Nd:SrGdGa3O7, and Nd:BaLaGa3O7. Among the Nd:ABC3O7 group members, Nd:SrLaGa3O7 exhibits superior laser properties. A maximum output power reaches 3.88 W under an absorbed pump power of 29.01 W, which is the highest CW output power using LD as the pump source for Nd:SrLaGa3O7 gain medium. Using a Cr4+:YAG crystal as a saturable absorber, the LD pumped passively Q-switched laser is also realized. With Nd:SrLaGa3O7, the shortest pulse width, the largest pulse energy, and the highest peak power are observed to be 10.6 ns, 60.3 μJ, and 5.3 kW, respectively. In the CW laser operation, wavelength tunings are also reported. The center wavelength of this Nd: SrGdGa3O7 laser shifts from 1062.48 to 1063.91 nm by changing the temperature from 60 °C to 135 °C.

Temperature tunable lasers with disordered Nd:ABC3O7 crystals

Luminescent properties of Y3Al5O12:Ce3+ phosphor-in-glass for WLEDs

Ce3+- or/and Dy3+-doped Mg2Al4Si5O18 phosphors have been fabricated via a sintering process at 1400°C for 5 h and their crystallinity and luminescence characteristics investigated. x-Ray powder diffraction analysis demonstrated that Ce3+/Dy3+ ions entered the Mg2Al4Si5O18 host and formed a solid solution. When excited at 345 nm, Ce3+-doped Mg2Al4Si5O18 phosphor emitted light in the blue region while Dy3+-doped Mg2Al4Si5O18 phosphor emitted light in the yellow region. When excited at 345 nm, emission bands located in both the blue and yellow regions were observed for the Ce3+/Dy3+-codoped Mg2Al4Si5O18 phosphor. Because of Ce3+ → Dy3+ energy transfers, the Ce3+/Dy3+-codoped Mg2Al4Si5O18 phosphor showed tunable luminescence, changing from the blue to yellow–green region through the white region with increasing Dy3+ concentration in the Ce3+/Dy3+-codoped Mg2Al4Si5O18 phosphor. The decay characteristics of the Ce3+ emission in the Ce3+/Dy3+-codoped Mg2Al4Si5O18 phosphors were also investigated. With increasing Dy3+ concentration, the lifetime of the Ce3+ emission decreased continuously, further confirming the occurrence of Ce3+ → Dy3+ energy transfer.

https://link.springer.com/content/pdf/10.1007/s11664-021-08806-x.pdf

Energy-Transfer-Induced Tunable Luminescence in Mg 2 Al 4 Si 5 O 12 :Ce 3+ /Dy 3+ Phosphors

CuFeS2, CuFeS1.8Se0.2, CuFeS1.6Se0.4 and CuFeS1.4Se0.6 nanoparticles were synthesized by a solvothermal method at 190 °C for 30 h. The obtained samples were tested by XRD, FTIR, BET, SEM and DRUVS, which explore the influence of Se-doping on grain size, structure, morphology and energy gap. Results show that the synthetic particles are nano-scale of chalcopyrite and with the increase of Se-doping content in CuFeS2, the grain size increases and the lattice parameters make a difference accordingly. Pore structure exists in CuFeS2 and CuFeS2−xSex, but their pore diameter and volume are tiny. Chalcopyrite nanoparticles with tetragonal phase are well-crystallized and the particle dispersion is improved after Se-doping. The band gap of CuFeS2 can be adjusted by Se-doping.

Chengcheng Qiu

Papers

Growth and optical properties of a promising Deep-ultraviolet birefringent crystal Ba2Mg(BO3)2

Temperature tunable lasers with disordered Nd:ABC3O7 crystals

Luminescent properties of Y3Al5O12:Ce3+ phosphor-in-glass for WLEDs

Energy-Transfer-Induced Tunable Luminescence in Mg 2 Al 4 Si 5 O 12 :Ce 3+ /Dy 3+ Phosphors

Synthesis and characterization of CuFeS 2 and Se doped CuFeS 2−x Se x nanoparticles