A kilowatt diode-pumped solid-state heat-capacity double-slab laser

A kilowatt diode-pumped solid state heat capacity laser is fabricated with a double-slab Nd:YAG. Using the theoretical model of heat capacity laser output laser characteristics, the relationships between the output power, temperature and time are obtained. The slab is 59 x 40 4.5mm(3) in size. The average pump power is 11.2kW, the repetition rate is 1kHz, and the duty cycle 20%. During the running time of 1s, the output energy of the laser has a fluctuation with the maximal output energy at 2.06J, and the maximal output average power is 2.06kW. At the end of the second, the output energy declines to about 50% compared to the beginning. The thermal effects can be improved with one slab cooled by water. The experimental results are consistent with calculation data.

水下目标光学隐蔽深度遥感获取方法

针对用透明度盘深度(SD)估计水下目标的光学隐蔽深度(OCD)的方法缺乏科学性与准确性,提出了利用水色卫星遥感数据获取水下目标光学隐蔽深度的方法。在给出水下目标光学隐蔽深度概念的基础上,分析了水下目标对水中光传输的影响,并根据目标背景对比度传输方程建立了水下目标隐蔽深度与透明度盘深度的转换关系。建立了水下目标光学隐蔽深度的遥感获取模式,并对模式进行了实验验证。结果表明,黑色模型的理论计算和实测数据的相对误差小于30%,而白色模型的理论计算和实测数据的相对误差小于20%。

A new species of Amolops (Anura : Ranidae) from Southwest China

A new species of Amolops is described from a mountainous area of southern Yunnan Province, China. The species is unique in having a dark purple dorsum with small light yellow spots. The spots are smaller than the smallest finger disk. Other characters tha

Effect of desert soil algae on the stabilization of fine sands

Four filamentous cyanobacteria, Microcoleus vaginatus, Phormidium tenue, Scytonema javanicum (Kutz.) and Nostoc sp., and a single-celled green alga, Desmococcus olivaceus, all isolated from Shapotou (Ningxia Hui Autonomous Region of China), were batch cultured and inoculated onto unconsolidated sand in greenhouse and field experiments. Their ability to reduce wind erosion in sands was quantified by using a wind tunnel laboratory. The major factors related to cohesion of algal crusts, such as biomass, species, species combinations, bioactivity, niche, growth phase of algae, moisture, thickness of the crusts, dust accretion (including dust content and manner of dust added) and other cryptogams (lichens, fungi and mosses) were studied. The best of the five species were M. vaginatus and P. tenue, while the best mix was a blend of 80% M. vaginatus and 5% each of P. tenue, S. javanicum, Nostoc sp. and D. olivaceus. The threshold friction velocity was significantly increased by the presence of all of the cyanobacterial species, while the threshold impact velocity was notably increased only by the filamentous species. Thick crusts were less easily eroded than thin crusts, while biomass was more effective than thickness. Dust was incorporated best into Microcoleus crust when added in small amounts over time, and appeared to increase growth of the cyanobacterium as well as strengthen the cohesion of the crust. Microbial crust cohesion was mainly attributed to algal aggregation, while lichens, fungi and mosses affected more the soil structure and physico-chemical properties.

光探测自旋共振对激子和带负电激子光学性质的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

高速激光器芯片的测试与封装技术的研究及2.5Gb/s DBF激光器与EA调制器单片集成器件的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

自组织InAs/GaAs量子点的光电性质和生长机理

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

立方氮化物及其蓝-绿光发光二极管的外延生长和性质研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

GaN基材料的生长、结构性能及光电性质研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

硅基二氧化硅AWG波分复用/解复用器的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

掺铒硅基材料光学性质和微结构研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

模糊逻辑处理两步式高速精度A/D转换器的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

立方相GaN的MOCVD外延生长和发光二极管的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

GaAs基应变自组装InxGa1-xAs量子点的生长、结构和光学性质的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

SiGe/Si MQW共振腔光电探测器

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z