蓬莱海市出现的气象水文条件分析

本文对1980～2007年间18次蓬莱海市出现的特征和气象水文条件进行了研究和分析,结果显示:蓬莱海市主要出现在5月下旬至8月上旬的100天之内,绝大多数出现在下午;春夏季节海市主要出现在降水停止后的36～48小时之内的晴好天气,冬季海市出现于山东半岛北部特有的冷流降雪的间隙;海市出现时的主要气象条件:日温差4.0～10.1℃;能见度主要在20～30km之间;风速在2～6.7m/s之间;春夏季节均以偏东风为主,冬季以西北风为主;蓬莱海市主要出现在望、朔日前后五日内,半数以上出现在望、朔日前后的三日内.     

Formation and early development of tetraspores of Polysiphonia urceolata （Rhodomelaceae, Rhodophyta）

Polysiphonia urceolata is one type of potential commercial red seaweeds used for breeding and cultivation, because of its significant biochemical and biomedical application. However, the information of breeding and seedling incubation for cultivation is limited, especially the early development. In this study, tetrasporohyte and gametophyte of P. urceolata were taken as the study materials in Huiquan Bay, Qingdao, China. The cleaned and sterilized tetrasporophytes and gametophytes were pre-cultured in sterilized seawater, then nurtured at 18°C, 25 μmol photons m⁻² s⁻¹ in 12:12 h (light:dark) photoperiod. Continuous observation under microscope showed that the early development consists of bipolar division stage and seedling stage. In the division stage, tetraspores germinate into bipolar sporelings that further differentiate into a colorless rhizoidal portion and a lightly pigmented upright shoot. The lightly pigmented rhizoidal cell develops to a rhizoid and the larger pigmented cell transforms to an erect axis. In the seedling stage, several quasi-protuberances appear on the erect axis and form juvenile seedlings. The results demonstrate the culture of P. urceolata from tetraspores under laboratory conditions. Supported by National Key Technology Support Program, Development Program of China (No.2006AA09Z21), National Natural Science Foundation of China (No. 40618001 and N_CUHK438/06) and Shandong Agricultural Seed Stock Breeding Project     

Application of matter-element model in soil nutrient evaluation of ecological fragile region

On the basis of the soil environment investigation in Da'an City, Jilin Province, China, 40 soil samples from main land use types were obtained and tested by standard method. Soil organic matter (SOM), total N (TN), total P (TP), total K (TK), available N (AN), available P (AP) and available K (AK) were chosen as the evaluation factors. A regional soil nutrient evaluation model was developed based on the matter-element model. The results show that the soil samples with nutrient grade Ⅱ-Ⅴ respectively account for 10%, 30%, 32.5% and 27.5%, and those with grade Ⅳ and Ⅴ account for 60% in all samples. The relationship between soil nutrients and land types indicates that the nutrients of farmland are relatively good, with 41.7% of soil samples with the nutrient grade Ⅳ and Ⅴ. The nutrients of saline-alkali land and sandy land are the worst, with 100% of soil samples with the nutrient grade Ⅳ and Ⅴ. And the ratios of soil samples grade Ⅳ and Ⅴ in grassland and wasteland are respectively 62.5 % and 54.55%. Generally speaking, the soil nutrients status in Da'an City is poor, 60% of soil samples are in poor and extremely poor conditions, indicating that the soil has been severely eroded. Being a relatively superior evaluation method with more accurate resuits and spatial distribution consistency, matter-element analysis is more suitable for regional soil nutrient evaluation than previous models.     

浅谈"数字国土工程"技术与应用

“数字国土工程“是国家信息化建设的重要组成部分,是为各级国土部门的土地利用数据更新、综合统计、耕地保护、建设项目用地管理等日常国土资源管理业务提供数据支持和技术服务的重要手段。     

一种改进的Apriori挖掘算法

针对制约Apriori算法效率的瓶颈问题,提出了一种基于Apriori的改进算法,算法只需要遍历一次事务数据库,避免了Aprori算法多次扫描事务数据库和产生大量的候选项集,同时利用项集的有序性改进了判断连接的方式,优化了连接步骤,减少了判断时间.实验结果表明,改进的Apriori算法在运行效率上有一定的提高.     

矿产资源潜力评价

“在全国矿产资源潜力评价中,采用物探方法估算出辽宁、河北、四川、新疆、青海、安徽六省示范区还有相当可观的铁矿资源量。”这是日前在厦门召开的“全国矿产资源潜力评价典型示范中重、磁及遥感资料应用成果汇报及经验交流会”上获得的振奋人心的好消息。这次典型示范工作结束后,建立在示范工作经验和模式基础上的全国矿产资源潜力评价工作即将全面展开。     

浅谈八项质量管理原则在工勘施工企业中的应用

随着改革及施工市场的需要,工勘施工企业都需要进行质量体系认证工作.2000版质量管理体系国家标准在总结1994版质量管理体系国家标准实践的基础上明确提出了八项质量管理原则:以顾客为关注焦点、领导作用、全员参与、过程方法、管理的系统方法、持续改进、基于事实的决策方法以及与供方的互利关系.八项质量管理原则科学总结了世界各国多年来理论研究的成果和实践的经验,体现了质量管理的基本规律,是2000版GB/T19000族质量管理体系国家标准的基础.八项质量管理原则可以作为工勘施工企业制定质量方针的基础,工勘施工企业的最高管理者可以运用这些原则领导本单位进行业绩改进.实际上,这些原则不仅体现质量管理的基本规律,也适用于工勘施工企业的全部管理.质量管理原则的提出和应用,为进一步提高工勘施工企业质量管理的科学性,乃至为提高工勘施工企业管理科学性创造了条件.     

白银市农业气候资源特征及开发应用

白银市农业气候资源具有日照充足，降水少而变率大，气象灾害种类多、危害重的特点。提出了气候资源开发与应用的途径。     

武汉区域气象中心数值预报业务并行计算机系统

对武汉区域气象中心并行计算机系统进行了详细地介绍，分析了并行计算机体系结构、网络和存储系统特点；给出了在并行计算机SP上实现数值预报业务并行化的部分结果；对数值预报模式在串、并行编程环境下的结果进行了分析比较。     

转基因水生动物的应用研究

<正>1966年Lin首次报道了将外源基因注入小鼠卵中的显微注射方法[1]。1982年诞生了首例转基因动物——转基因小鼠[2]。1984和1985年转基因虹鳟[3]和鲫鱼[4]研究获得成功。经过二十多年来的努力,转基因水生动物尤其是转基因鱼的研究有了长