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我 国 休 闲 农 业 中 植 物 休 闲 活 动 研 究  [PDF]
张东梅1,张 彦2,吕 良2
北方园艺 , 2010, DOI: 10.11937/bfyy.201017092
Comparison Between Computer Simulation of Transport and Diffusion of Cloud Seeding Material Within Stratiform Cloud and the NOAA-14 Satellite Cloud Track
YU Xing,DAI Jin,LEI Hengchi,FAN Peng,
YU Xing
,DAI Jin,LEI Hengchi,FAN Peng

大气科学进展 , 2005,
Abstract: A precipitation enhancement operation using an aircraft was conducted from 1415 to 1549 LST 14 March 2000 in Shaanxi Province. The NOAA-14 satellite data received at 1535 LST soon after the cloud seeding shows that a vivid cloud track appears on the satellite image. The length, average width and maximum width of the cloud track are 301 km, 8.3 and 11 km, respectively. Using a three-dimensional numerical model of transport and diffusion of seeding material within stratiform clouds, the spatial concentration distribution characteristics of seeding material at different times, especially at the satellite receiving time,are simulated. The model results at the satellite receiving time are compared with the features of the cloud track. The transported position of the cloud seeding material coincides with the position of the track. The width, shape and extent of diffusion of the cloud seeding material are similar to that of the cloud track.The spatial variation of width is consistent with that of the track. The simulated length of each segment of the seeding line accords with the length of every segment of the track. Each segment of the cloud track corresponds to the transport and diffusion of each segment of the seeding line. These results suggest that the cloud track is the direct physical reflection of cloud seeding at the cloud top. The comparison demonstrates that the numerical model of transport and diffusion can simulate the main characteristics of transport and diffusion of seeding material, and the simulated results are sound and trustworthy. The area, volume, width, depth, and lateral diffusive rate corresponding to concentrations 1, 4, and 10 L-1are simulated in order to understand the variations of influencing range.
Numerical Simulation of Distribution and Evolution of Supercooled Liquid Water in Seeding Stratiform Cloud

LIU Xiao-Li,NIU Sheng-Jie,CHEN Yue,

大气科学 , 2006,
Abstract: Two materials are usually used for cold cloud seeding agents.One is coolant agent such as solid,liquid CO_(2)or N_(2),and they can generate ice crystals by strong cooling,the other agent,such as AgI,can be ice-forming nuclei.The important advantage of the coolant agent is that a number of generated ice crystals is nearly independent of the temperature. Since dry ice pellets have high fall velocity and have to be dropped from high altitudes,Fukuta(1996a,b) suggested a method to seed the liquid CO_(2) horizontally at the lower level of the supercooled portion of cloud.The objectives of this study are to compare the effect of the newly proposed cloud(seeding agent-liquid CO_(2) with current widely used seeding agent-AgI on cloud dynamics,cloud microphysics and precipitation evolution,especially the distribution and evolution of supercooled liquid water in seeded stratiform cloud.A one-dimensional rain category model developed by Guo Xueliang et al.(1999) is employed in this study with ice multiplication available.The contact and deposition nucleation processes of the seeding agents are considered as only inertial impact and Brownian collection are considered as a possible mechanism for contact nucleation.As a cooling agent,the cooling process due to vaporization and heat conduction between the seeded air and the liquid CO_(2) droplets are also included into this model to explore the cooling effect of liquid CO_(2) on the seeded cloud.Seeding rate is set to 0.06 g/s for both AgI and liquid CO_(2) in all seeded cases and seeding was starting at 170 min.Both AgI and liquid CO_(2) were released continuously for 10 min,20 min and 30 min in 52005600 m and 26003000 m levels,respectively.The simulations indicate that the liquid CO_(2) and AgI seeding in 52005600 m levels have nearly the same seeding effect which can reach to 11.1%,while that of liquid CO_(2)seeding at 26003000 m levels can reach 14.2%;and the cooling effect of liquid CO_(2) is found to be very faintness at the same time;when it comes to the seeding effect on cloud microphysics,growth of super cooled water begin at 200 min after depleted by seeding process;and the vapour content reduces 0.5 g/m~(3)2 g/m~(3) after seeding and contribute to the growth process of super cooled water;the concentration of rain droplet reduces 73% at 210 min and increases 309% at 230 min as compared to the condition without seeding.The conclusions can be made that:(1) Growth process of supercooled cloud water appears at 200 min after depleted with the vapour content contributed to the growth process;(2) better seeding effect can be achieved by seeding liquid CO_(2) in the region with more supercooled liquid water.
Observation Research on Cloud Microphysics and Precipitation Affection of Stratiform Cloud Seeding by Liquid Carbon Dioxide

JIN De-Zhen,LEI Heng-Chi,ZHENG Jiao-Heng,XIAO Hui,CUI Lian,WU Yu-Xia,LIU Jian,

大气科学 , 2007,
Abstract: The detail information is deduced on the microphysical affection of stratiform cloud seeding,including in situ aircraft measurements,radiosondes,radar data,and surface observations in the experiment of precipitation enhancement in Jilin Province during 11-12 July 2002.The results indicate that the maximum of cloud super cooled liquid water content reaches 0.1-0.2 g/m~3,but the concentration of ice crystal is very low for nature cloud.It means that the cloud is eligible for precipitation enhancement seeding according to principle of weather modification.The changes of cloud microphysical structure,such as the increasing of ice crystal concentration and diameter of rain droplets,the decreasing of super cooled liquid water content,are caused by seeding liquid CO_2.The increase in radar echo intensity in the incidence area comparing with the target area is also caused by cloud seeding,which is similar to the increase in concentration of rain droplets observed by in situ aircraft.For the precipitation intensity in the incidence area of cloud seeding increases but it only slightly changes in the comparison area.The redistribution of rainfall is caused by cloud seeding in the precipitation area.
无 氧 条 件 下TiO2 薄 膜 界 面 光 催 化 反 应 的XPS 研 究  [PDF]
杨喜昆,胡显智,何 兵,楚国栋
分子催化 , 2009,
Abstract: 设 计 利 用 X 射 线 光 电 子 能 谱 仪 的 高 真 空 系 统 作 为 无 氧 条 件 下 光 催 化 反 应 和 分 析 的 场 所 , 研 究 真 空 无 氧 环 境 和 大 气 有 氧 环 境 中 紫 外 光 激 发 TiO2 薄 膜 表 面 的 光 催 化 反 应 , 并 对 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 进 行 初 步 探 索 . 结 果 表 明 , 在 大 气 有 氧 和 真 空 无 氧 条 件 下 TiO2 薄 膜 经 紫 外 光 照 后 , 表 面 的 化 学 组 成 和 化 学 状 态 均 发 生 了 变 化 ; 在 有 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 增 加 , 而 在 无 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 减 少 . TiO2 薄 膜 表 面 的 吸 附 氧 是 维 持 无 氧 条 件 下 光 催 化 反 应 的 重 要 原 因 , 增 加 薄 膜 表 面 吸 附 氧 的 含 量 能 提 高 TiO2 薄 膜 在 无 氧 环 境 中 的 催 化 活 性 . 此 外 , 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 光 催 化 反 应 过 程 中 , 亚 甲 基 蓝 分 子 只 是 脱 去 了 某 个 含 氮 的 基 团 , 生 成 了 中 间 产 物 , 而 并 没 有 完 全 降 解 .
珙 桐 繁 育 的 研 究 进 展  [PDF]
陈蕤坤,徐 莺
北方园艺 , 2010, DOI: 10.11937/bfyy.201023075
百 合 鳞 片 快 繁 试 验 研 究  [PDF]
王海新,赵 艳,崔雪艳
北方园艺 , 2010, DOI: 10.11937/bfyy.201017056
金 钱 松 研 究 进 展 与 展 望  [PDF]
北方园艺 , 2010, DOI: 10.11937/bfyy.201020076
土 壤 氮 素 矿 化 研 究 进 展  [PDF]
张笑千,陈 卓,常 鹏,曲英华
北方园艺 , 2010, DOI: 10.11937/bfyy.2010015008
茄 子 杂 种 优 势 利 用 研 究  [PDF]
樊绍翥,张凤生,李 烨,姚建刚
北方园艺 , 2010, DOI: 10.11937/bfyy.201023007
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