本文提出一种宽频左手材料结构,其通过多开口谐振结构在不同频带实现谐振。通过理论分析,软件仿真与介质参数提取对设计结构左手特性进行验证。结果表明该结构在谐振频带具有宽频左手特性(等效磁导率μ与等效介电常数ε均小于零),左手...本文提出一种宽频左手材料结构,其通过多开口谐振结构在不同频带实现谐振。通过理论分析,软件仿真与介质参数提取对设计结构左手特性进行验证。结果表明该结构在谐振频带具有宽频左手特性(等效磁导率μ与等效介电常数ε均小于零),左手频带为:10.3~18.35 GHz,相对带宽57.71%,单元损耗小于0.9 d B,相较于传统左手材料结构,左手频带更宽,并且结构简单易于分析和应用。展开更多
针对45#钢进行切削,以YT15车刀为对比,研究了CrAlN纳米梯度涂层的切削性能,利用Fluke Ti X640型热成像仪测试了切削过程中切削区的切削温度,采用超景深三维显微镜观察了刀具的磨痕形貌。结果表明:CrAlN纳米梯度涂层刀具具有更低的切削温...针对45#钢进行切削,以YT15车刀为对比,研究了CrAlN纳米梯度涂层的切削性能,利用Fluke Ti X640型热成像仪测试了切削过程中切削区的切削温度,采用超景深三维显微镜观察了刀具的磨痕形貌。结果表明:CrAlN纳米梯度涂层刀具具有更低的切削温度,使用寿命比YT15车刀使用寿命约延长了1.5倍。刀具磨损失效以磨料磨损为主。展开更多
In the fabrication of surface relief gratings （SRGs） on azobenzene polymer films with a zeroth-order suppressed diffraction phase mask, it is found that the SRGs＇ relief figure and period change with the irradiatio...In the fabrication of surface relief gratings （SRGs） on azobenzene polymer films with a zeroth-order suppressed diffraction phase mask, it is found that the SRGs＇ relief figure and period change with the irradiation time, and the period is doubled after a critical time. The time dependence of the changes in the SRG forming process is investigated by theoretical analysis and experiments. An optimum time range for inscription of the sub-micron SInGs is determined to be 5-8 rain in terms of both the theoretical and experimental results.展开更多
A single-mode polymer optical fiber （POF） with highly photosensitive core doped with benzil dimethyl ketal （BDK） is fabricated and used for writing Bragg grating through the two-beam interference method. The Bragg...A single-mode polymer optical fiber （POF） with highly photosensitive core doped with benzil dimethyl ketal （BDK） is fabricated and used for writing Bragg grating through the two-beam interference method. The Bragg wavelength of the grating is about 1570 nm, while the full-width at half-maximum （FWHM） of the reflection peak is 0.3 nm. The temperature response of POF Bragg grating is theoretically analyzed and experimentally measured in contrast to silica optical fiber Bragg grating （FBG）. The result shows that the temperature character of POF Bragg grating is negative, which is opposite to the silica optical FBG. The absolute value of the temperature response of POF Bragg grating is one order of magnitude higher than that of the silica optical FBG, making POF Bragg grating appear to be very attractive for constructing temperature sensors with high resolution.展开更多
文摘本文提出一种宽频左手材料结构,其通过多开口谐振结构在不同频带实现谐振。通过理论分析,软件仿真与介质参数提取对设计结构左手特性进行验证。结果表明该结构在谐振频带具有宽频左手特性(等效磁导率μ与等效介电常数ε均小于零),左手频带为:10.3~18.35 GHz,相对带宽57.71%,单元损耗小于0.9 d B,相较于传统左手材料结构,左手频带更宽,并且结构简单易于分析和应用。
文摘针对45#钢进行切削,以YT15车刀为对比,研究了CrAlN纳米梯度涂层的切削性能,利用Fluke Ti X640型热成像仪测试了切削过程中切削区的切削温度,采用超景深三维显微镜观察了刀具的磨痕形貌。结果表明:CrAlN纳米梯度涂层刀具具有更低的切削温度,使用寿命比YT15车刀使用寿命约延长了1.5倍。刀具磨损失效以磨料磨损为主。
基金Supported by the National Natural Science Foundation of China under Grant Nos 50703038, 50773075 and 50533040, the Knowledge Innovation Project of Chinese Academy of Sciences （KJCX3.SYW.H02 and KJCX2-YW-M11）, China Postdoctoral Science Foundation （No 20100470038）, and the National Basic Research Program of China under Grant No 2006cb302900.
文摘In the fabrication of surface relief gratings （SRGs） on azobenzene polymer films with a zeroth-order suppressed diffraction phase mask, it is found that the SRGs＇ relief figure and period change with the irradiation time, and the period is doubled after a critical time. The time dependence of the changes in the SRG forming process is investigated by theoretical analysis and experiments. An optimum time range for inscription of the sub-micron SInGs is determined to be 5-8 rain in terms of both the theoretical and experimental results.
基金supported by the National Natural Science Foundation of China (Nos. 50703038, 50773075,21074123, and 50973101)the Chinese Academy of Sciences (Nos. kjcx3.syw.H02 and kjcx2-yw-m11)+1 种基金China Postdoctoral Science Foundation (No. 20100470038)the "Hundred Talents Program" of the Chinese Academy of Sciences
文摘A single-mode polymer optical fiber （POF） with highly photosensitive core doped with benzil dimethyl ketal （BDK） is fabricated and used for writing Bragg grating through the two-beam interference method. The Bragg wavelength of the grating is about 1570 nm, while the full-width at half-maximum （FWHM） of the reflection peak is 0.3 nm. The temperature response of POF Bragg grating is theoretically analyzed and experimentally measured in contrast to silica optical fiber Bragg grating （FBG）. The result shows that the temperature character of POF Bragg grating is negative, which is opposite to the silica optical FBG. The absolute value of the temperature response of POF Bragg grating is one order of magnitude higher than that of the silica optical FBG, making POF Bragg grating appear to be very attractive for constructing temperature sensors with high resolution.
