中国滑雪场可达性及市场潜力测度

利用可达性分析方法与潜力模型对中国滑雪场空间分布格局与市场潜力进行了系统分析,全面认识了滑雪场在交通可达性方面的优劣势,并针对不同区域提出了相应的发展或改进方向.研究表明:中国滑雪场距离城市中心的平均最短旅行时间为1.24 h,南方可达性普遍较差,北方同一城市内部差异较大.全国各城市到达某一滑雪场的最短时间呈圈层式分布...     

赵九章先生对推进我国地震科学事业的贡献

赵九章先生是一位开拓性的科学家,眼光看得远,只要国家需要就干。他的领导艺术和组织才能也是众所周知的。1950年4月6日,中国科学院建立地球物理研究所,任命赵九章为所长,下属气象、地磁、地震和物探4个组。在赵九章所长领导下,4个组都得到了重大发展,以致分别发展为大气物理、     

基于小波神经网络耦合模型对云南星云湖富营养化气象驱动因子的分析

气象因子是影响湖泊富营养化的重要因素,而湖泊富营养化对人群健康、生态系统和社会经济等均有负面影响.本文基于统计资料及遥感数据,结合Morlet小波分析和BP多层前馈神经网络(BP神经网络)构建了不同时间尺度下的小波神经网络耦合模型,分析了19862011年云南星云湖水华强度变化与月降雨量、月平均气温、月平均风速、月日照...     

地面塌陷及地裂缝的成因及防治——葫芦岛市南票区及连山区矿产开采引起的地质灾害

由于大规模地开发矿产资源及频繁的经济活动,使葫芦岛市南票、连山两区成为地质灾害的多发区。引起的地质灾害分布范围广,危害程度大,已造成巨大的经济损失和大量人员伤亡,严重地制约着地方经济和社会的可持续发展,危害着人民群众生命财产安全。通过对相关矿山采空区地面塌陷、地裂缝进行调查研究。对该市地质灾害的分布特征、地质灾害的成因机理有了比较系统的认识。由此进一步提出了该市两区地质灾害的防治对策,力求有效地预防和减少地质灾害的发生.     

Paleoenvironmental implications of the guano phosphatic cementation on Dongdao Island in the South China Sea

The phosphatic cement in the bioclastic sediment sequence on the northeastern shore of Dongdao Island in the South China Sea was studied and its paleoenvironmental implications discussed. Petrological characteristics and major, trace, REE element data unequivocally supported the notion that phosphatization was closely associated with avian guano decomposition and leaching, whereas carbon and oxygen isotope results further revealed that meteoric water were involved in these processes. AMS ¹⁴C dates on the brown phosphate cements indicate that they were formed around 5700, 5000–5100 and 2900 yr BP, respectively. The multi-episodes of phosphatization very likely correspond to intermittent seabird occupation on this island — possibly reflecting Holocene sea-level oscillation and/or long term climate changes in the South China Sea that have controlled seabird habitat. The phosphate cementation, which occurs widely in tropical islands, may be another useful monitor for sea-level and/or paleoclimate changes.     

双水相萃取法富集分离螺旋藻藻蓝蛋白的研究

以PEG／硫酸钠双水相体系,经一次萃取从钝顶螺旋藻（Spirulina platensis）细胞破碎液中富集分离藻蓝蛋白。结果表明,萃取最适宜的条件为12％PEG4000,15％Na2SO4,1％KCl,藻蓝蛋白收率为91．2％,分配系数达到8．01,分离因数达到6．33。对于螺旋藻藻蓝蛋白的富集分离,双水相萃取法与传统的盐析沉淀法相比,具有节省操作时间、简化操作过程、降低能耗和成本以及易于工艺放大等优点。     

Optimum temperature for the growth performance of juvenile orange-spotted grouper （Epinephelus coioides H.）

Effects of water temperature （17, 21, 25, 30 and 35℃） and body size （14.75-281.41 g initial body weight） on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satiation were investigated. The combined effect of temperature （T, ℃） and body weight （W, g） on maximum food consumption （Cmax, g/day） was described as： InCmax=-7.411＋0.828 InW＋0.317T4）.004 7T2, and the optimum feeding temperature was 33.9℃. The combined effect of temperature and body weight on growth （G） was described as： lnG=-4.461-0.2081nW＋0.394T-0.006 3T^2. The optimum growth temperature was 31.4℃, whereas overall growth rates were high at 25, 30 and 35 ℃. Feed conversion efficiencies （FCE, %）, increasing first and then decreasing with increasing temperature, averaged from 1.8 to 2.1 in terms of dry weight of food fish. The optimum temperature for FCE tended to be lower than that for growth or feeding. Dry matter content increased with both increasing water temperature （17, 25, 30 and 35℃） and body weight, and the combined effect of temperature and body weight on dry matter content （DM, %） was described as： lnDM =3.232＋0.01 4 lnW-0.004 4T＋0.001 2TInW.     

��ά�ռ����ά�ռ��߲���ת����������·���

????????????δ?????????????????????????????????·?????????????????????????????????????????????????????????÷?Χ???ó?????:????γ??????Χ??С??8???,??x??y???????????????1 cm??????????侫???????γ??(?????γ??)??Χ????С??????????     

《昆明市城市排水系统分布专题地图》的编制研究

本文就利用ARCMAP软件编制<昆明城市排水系统分布专题地图>的实践过程,尝试将地图编制与排水管线地理信息系统建设实现很好的结合,实现图-库一体化联接,并最终实现以地下管线探测数据的地图可视化过程,从而完成专业管线专题地图的编制,为城市排水规划、建设与决策提供直观依据.