机构

• 地理科学与资源研究所 [4]
• 长春光学精密机械与物... [1]

采集方式

• OAI收割 [5]

内容类型

• 期刊论文 [4]
• 会议论文 [1]

发表日期

• 2020 [1]
• 2018 [3]
• 2005 [1]

学科主题

筛选

浏览/检索结果: 共5条，第1-5条 帮助 条数/页： 5101520253035404550556065707580859095100 排序方式： 请选择题名升序题名降序提交时间升序提交时间降序作者升序作者降序发表日期升序发表日期降序 新安江流域行政区经济非均衡性的行政边界效应 期刊论文  OAI收割 经济地理, 2020, 卷号: 40, 期号: 9, 页码: 46 作者:  任以胜;  陆林;  虞虎   |  收藏  |  浏览/下载：19/0  |  提交时间：2021/03/16 administrative region  non-equilibrium  administrative border effect  the Xin'an River basin  regional economic integration  economic development level  行政区  非均衡  行政边界效应  新安江流域  区域经济一体化  经济发展水平   The border effect on urban land expansion in China: The case of Beijing-Tianjin-Hebei region 期刊论文  OAI收割 LAND USE POLICY, 2018, 卷号: 78, 页码: 287-294 作者:  Wang, Chenglong;  Liu, Hui;  Zhang, Mengtian;  Wei, Zongcai   |  收藏  |  浏览/下载：31/0  |  提交时间：2019/05/23 Urban land expansion  Border effect  The stage model  Beijing-Tianjin-Hebei   The border effect on urban land expansion in China: The case of Beijing-Tianjin-Hebei region 期刊论文  OAI收割 LAND USE POLICY, 2018, 卷号: 78, 页码: 287-294 作者:  Wang, Chenglong;  Liu, Hui;  Zhang, Mengtian;  Wei, Zongcai   |  收藏  |  浏览/下载：37/0  |  提交时间：2019/05/23 Urban land expansion  Border effect  The stage model  Beijing-Tianjin-Hebei   The border effect on urban land expansion in China: The case of Beijing-Tianjin-Hebei region 期刊论文  OAI收割 LAND USE POLICY, 2018, 卷号: 78, 页码: 287-294 作者:  Wang, Chenglong;  Liu, Hui;  Zhang, Mengtian;  Wei, Zongcai   |  收藏  |  浏览/下载：18/0  |  提交时间：2019/05/23 Urban land expansion  Border effect  The stage model  Beijing-Tianjin-Hebei   Research on LD-Pumped dual wavelength Nd:YAG Laser with high beam quality for machining (EI CONFERENCE) 会议论文  OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者:  Zhang G.;  Zhang G.;  Zhang G.;  Zhang J.;  Zhang J. 收藏  |  浏览/下载：34/0  |  提交时间：2013/03/25 Considering laser medium thermal lens effect and thermal focal length changes with pumping power  conventionally  lasers are designed to operate in the middle of thermal stable zones  where the fundamental mode size is insensitive to thermal perturbation  while this method seems impossible when large fundamental mode size is required. Through self-select mode cavity  lasers are designed to work at the border of stable zone instead  where large fundamental mode size in gain media can be reached. With increase of pumping power and self-aperture mode-selective effect  mode size would grow up automatically to a certain value suitable for monomode resonance. With double 180 W pump modules  acoustic Q-switch and LBO external frequency-doubled  over 28 W which M2 equals 4.5 quasi-CW output green laser and 52W 1.064 um IR output is obtained simultaneity. With the insertion or not of the harmonic separator by footswitch  high beam quality green  IR  and green IR lasers are obtained conveniently.