[en] Planar waveguides were formed in LiTaO₃ crystals by using 6.0-MeV C³⁺-ion implantation at room temperature. The prism-coupling method was used to take dark mode measurements at both 633 nm and 1539 nm. The reflectivity calculation method was used to reconstruct the refractive index profile in the waveguide. TRIM'98 (Transport of Ions in Matter) was also used to simulate the damage distribution in the LiTaO₃. Barrier-confined waveguides were found to be formed in LiTaO₃. Possible reasons for the different refractive-index profiles in the LiTaO₃ and the LiNbO₃ waveguides are discussed.

[en] Rare-earth garnet single-crystals are promising candidates for optical applications. Previous reports showed that they have controllability and good reservation of Nd ions fluorescent properties in the ion implanted waveguide. Thus, we studied the optical and fluorescent properties of the Nd:YGG waveguide structure formed by multi-energy He ion implantation. The fabrication and characterization of the optical planar waveguide in Nd:YGG crystal by using multi-energy He ion implantation was presented. The thermal stability of our ion-implanted Nd:YGG crystal was investigated. The guided-mode and annealing properties at the wavelength of 633 nm were investigated through prism-coupling and end-face coupling measurements, and the fluorescent properties were investigated by a confocal micro-luminescence experiment. This work could supply an operation reference for integrated optical devices

[en] This paper introduces the monitoring results of environmental gamma radiation air absorbed dose rate by Zhejiang Province Radiation Environmental Monitoring Center during Japan nuclear leakage accident. Monitoring includes continuous and instantaneous surveillance measurements in Hangzhou and Zhoushan areas and around Qinshan nuclear power base. The results indicated that Japan nuclear leakage accident caused by the earthquake did not significantly influence the environmental gamma radiation air absorbed dose rate level in Zhejiang Province. (authors)

[en] Optically polished LiNbO₃ was implanted by 3.0 MeV B³⁺ ions at room temperature, forming planar optical waveguides at a dose of 4 x 10¹⁴ ions/cm². The prism-coupling method was used to take dark mode measurements. Four waveguide modes were observed for both ordinary and extraordinary light. Contrary to high-dose ion-implanted waveguides, the extraordinary refractive index was found to increase in the guide region for low-dose implantations. The reflectivity calculation method was used to reconstruct the refractive index profile in the waveguide. TRIM'98 was also used to simulate the damage distribution in the LiNbO₃

[en] Planar optical waveguides were formed in Ce:SBN and Cu:KNSBN crystals, respectively, by means of 6.0 MeV B³⁺ ion implantation at a dose of 2x10¹⁴ ions/cm² at room temperatures. The prism coupling method was performed to characterize the dark-mode property of the waveguides. The reconstructed refractive index profiles in the waveguides were found to be typical barrier-type distributions. Transport and range of ions in matter (TRIM 98) code was used to simulate the process of the implantations. The shapes of nuclear energy loss distribution of the B³⁺ implantation were similar to those of the waveguide refractive index profiles, which means an inherent relationship between the waveguide formation and the energetic energy deposition

[en] Structures and electronic properties of 2Meq_2AlOC_6H_4R (R=CN, Cl, H, OMe, NMe_2) have been studied in the scheme of density function theory with the B3LYP and the 6-31G (d) basis set. The substitutions of the electron-withdrawing groups (CN, Cl) increase the band gap while the substitutions of the electron-donating groups (OMe, NMe_2) decrease the gap. The substitutions of electron-withdrawing groups enhance the electron injection ability. In addition, the vertical ionization energies (IE_V), the vertical electronic affinities (EA_V) and reorganization energies of 2Meq_2AlOPh and its derivatives are calculated in the work. All complexes are better electron transport materials. (paper)

[en] A planar optical waveguide was formed in RbTiOPO₄ (RTP) crystal by 3.0-MeV He-ion implantation with a dose of 1.0 × 10¹⁶ ions/cm² at room temperature. The prism-coupling method was used to take dark mode measurements at 633 nm. The refractive-index profile of the He-implanted RTP waveguide was analyzed with the reflectivity calculation method. The sample was annealed at 200 °C for 60 min in air. After annealing the intensity profile of the guide mode was obtained by end-fire coupling. The annealing process effectively removed the color centers and reduced the loss of waveguide.

[en] In order to improve the joint's properties, local heat treatment of TC4 titanium alloy with electron beam was conducted. After electron beam local heat treatment, residual stresses of weld were tested by the X-ray method. Compared with EBW, the martensite grains of weld become finer after electron beam local heat treatment, and residual stress distribution of TC4 titanium alloy joints is improved. (authors)

[en] Synchronizability of complex oscillators networks has attracted much research interest in recent years. In contrast, in this paper we investigate numerically the synchronization speed, rather than the synchronizability or synchronization stability, of identical oscillators on complex networks with communities. A new weighted community network model is employed here, in which the community strength could be tunable by one parameter δ. The results showed that the synchronization speed of identical oscillators on community networks could reach a maximal value when δ is around 0.1. We argue that this is induced by the competition between the community partition and the scale-free property of the networks. Moreover, we have given the corresponding analysis through the second least eigenvalue λ₂ of the Laplacian matrix of the network which supports the previous result that the synchronization speed is determined by the value of λ₂

[en] Highlights: • The first study to compare the offspring of invasive and native plants following sublethal exposure of parent to herbicides. • Sublethal atrazine and tribenuron-methyl had effects on the germination and seedling growth of the F1 generation of plants. • The response of the F1 generation of invasive plants and native plants to herbicides was different. • The herbicide inhibition effect on the F1 velvetleaf and redroot pigweed did not increase as the sublethal dose increased. The effects of sublethal doses of herbicides on plants cannot be ignored, yet little is known about the effects of sublethal doses of herbicides on the F1 generation of plants. Seed germination and seedling growth of native and invasive plants following the sublethal exposure of parent plants to herbicides were comparatively analyzed in this study. Sublethal atrazine and tribenuron-methyl had carry-over effects on the germination and seedling growth of the F1 generation of invasive redroot pigweed (Amaranthus retroflexus L.) and native velvetleaf (Abutilon theophrasti Medicus), both of which had different responses to the carry-over effects of sublethal herbicide. The germination percentage of the F1 redroot pigweed (decreased) was greater than that of the F1 velvetleaf (increased or not significantly changed) following parental exposure to atrazine or tribenuron-methyl. Atrazine reduced the radical growth of 7-day-old velvetleaf seedlings and decreased the difference in seedling length between velvetleaf and redroot pigweed, while tribenuron-methyl had no significant effects on the growth of 7-day-old velvetleaf seedlings. The herbicide inhibition effect on the germination and growth of F1 velvetleaf and redroot pigweed did not increase as the sublethal dose increased. This study suggests that carry-over effects of sublethal herbicides weaken the growth advantage of the F1 velvetleaf at the seedling stage and may have a more negative influence on progeny population development of native velvetleaf compared with invasive redroot pigweed.