生命周期视角下建成环境对居民休闲体力活动的影响

近年来,建成环境对居民休闲体力活动的影响受到广泛的关注,但这种影响对于生命周期不同阶段居民来说是否存在差异需深入研究。因此,本文基于生命周期理论,将广州市居民划分为无子阶段、满巢阶段Ⅰ、满巢阶段Ⅱ、空巢期四个阶段,利用多元线性回归方程,研究建成环境对生命周期不同阶段居民休闲体力活动影响的差异。研究发现：（1）各阶段居民散步、中等强度、高强度休闲体力活动的频率和时间差异显著,但休闲体力活动水平无明显差异。（2）由于各阶段居民生活方式和休闲行为不同,建成环境对其休闲体力活动水平的影响存在差异。各阶段居民都受到康体设施密度的正向影响。此外,无子阶段居民偏好多样化且中高强度休闲体力活动,因此受POI密度和交叉口密度正向影响较大。满巢阶段Ⅰ与满巢阶段Ⅱ的居民受到家庭束缚较大,受建成环境影响较小。空巢期居民偏好于散步,受土地利用多样性的正向影响较大,土地利用多样性高的地区,空巢期居民出门活动的几率更高。考虑到各阶段人群特征及需求差异,应采取差异化的建成环境改善措施,提供个性化的服务供给。     

碱性红13分光光度法测定氰化物浸出液中金(Ⅰ)的研究及应用

本文研究和确定了碱性红13显色、乙酸异戊酯萃取光度法,直接测定氰化物浸出液中金(I)的条件和方法。Au(CN)_2离子与显色剂形成1:1的离子缔合型配合物被乙酸异戊酯萃取,在有机相中至少稳定22h,配合物在540nm波长处有最大吸收,表观摩尔吸光系数ε_((?)40)=4.4×10~4L·mol~(-1)·cm~(-1)。金含量在0～20ug/5ml乙酸异戊酯范围内符合比尔定律。方法具有简便、快速、重现性好、毒性较小、成本低、实用性较强等优点,用于金矿浸出液的分析,结果令人满意。     

SSM/I Measured Microwave Brightness Temperature (TB's), Anomalies of TB's,and Their Relationship to Typhoon Intensification

The SSM/I microwave Brightness Temperatures (TB's) in the frequency domains of 85 and 19 GHz gathered from the Defense Meteorological Satellite Program (DMSP)-F8 satellite form the basis of this research. These data are related to 27 map times of 13 typhoons of the 1987 season, one typhoon of the 1988 season and one cyclone in the Indian Ocean in 1987. The TB's disclosed certain characteristics of typhoons unavailable through conventional infrared (IR) imagery means.Brightness Temperatures were chosen to delineate the typhoon characteristics rather than the derived geophysical parameters such as rainfall or surface winds because the TB's have better resolution. The footprint size of the 85 GHz TB is 15 × 13 km while a derived (through algorithms based on regression) quantity such as rainfall has a much higher footprint size. The relatively large footprint size of rainfall results, because of using the 19 GHz channel which has a larger footprint size of 69 × 43 km.The mean 85 GHz (vertically polarized, V) TB's of a moving typhoon, particularly those on the left side within 55 km of the center, appear to exhibit a practically usable correlation with the 24 hour intensity. This finding is consistent with some observational studies, which show higher rain rates to occur within the asymmetric eyewalls of developing tropical cyclones. Further stratification of the sample in terms of direction of movement improved the correlation.The TB anomalies were defined in terms of the TB differences between two sections of a typhoon (e.g., between right and left sides or between inner and outer areas). The development of this sort of anomalies represents a relative growth of deep convection close to the center. If there is a good growth, the cyclone is likely to intensify within a short period of time. The anomalies also showed good correlation with the 24-h intensity. The intensity change (24-h intensity – Current Intensity) was also correlated with the 85 GHz V mean TB values, as well as, with 85 GHz V TB anomalies as defined above. Significant correlations ensued. Since these preliminary results are promising, further experimentation with a larger sample is suggested. Nevertheless, the scientist interested in natural hazards would find the current results valuable in the problem of typhoon intensification.     

遥感-测站相结合的动态雪深反演方法初探

该文结合2000年专用传感器微波成像仪(SSM/I)的亮温数据和我国观测站雪深资料,提出了一种遥感-测站相结合的动态雪深反演方法,试图用统计关系的时空动态化方案克服理论上亮温与不同类型积雪之间物理关系的复杂性,从而提高测站稀疏区和雪盖边缘区的雪深反演精度。其最大特点在于反演系数并不固定,而随时间和空间变化,较好地改善了单一系数反演方法中积雪物理性质的区域性差异和时间(季节)性差异带来的反演误差。初步分析表明:这种遥感-测站相结合的反演方法所得的积雪空间分布连续性好,在雪盖边缘区和站点稀疏区也能得到较合理的雪深数据;与静态遥感反演法和可见光雪盖面积相比,这种方法克服了它们在华北和华中低估雪盖面积的缺点,积雪面积分布更接近真实场,对西部积雪分布的反演也有一定改善。     

闽三角城市群地质灾害敏感性评价

生态安全是地区社会经济可持续的根本保障,然而地质灾害会对地区的生态安全造成严重威胁,对闽三角城市群进行地质灾害敏感性分析具有重要意义。本文分别选取坡度、高程、土壤类型、NDVI、岩性、多年平均降水量、距主要公路距离和5 km格网内的地质灾害点数目这8个指标,基于SPCA、全局Moran's I和局部Moran's I,对闽三角城市群的地质灾害敏感性进行综合评价。结果表明：闽三角城市群整体处于中度敏感,不同敏感性的面积大小顺序为：中度敏感>高度敏感>轻度敏感>极敏感>不敏感,占比分别为26.96%、25.67%、23.89%、11.75%和11.72%;地质灾害敏感性由东南沿海向西北内陆呈现出由不敏感向极敏感逐渐过渡的整体趋势,并存在着明显的地带性特征;不同县（市、区）间及其内部的地质灾害敏感性均存在较大的空间异质性;地质灾害敏感性存在显著的空间自相关性,且为显著正相关,并呈现出显著的空间集聚性特征,在德化县、永春县、安溪县和南靖县为高高聚集,在惠安县、丰泽区、鲤城区、晋江市和石狮市为低低聚集;不同土地利用类型下的地质灾害敏感性综合指数大小顺序为：林地>草地>未利用地>耕地>水域>建设用地,林地和草地整体处于中度敏感,水域、耕地、建设用地和未利用地整体处于轻度敏感;多年平均降水量、坡度、距主要公路距离、地质灾害点数目、岩性和土壤类型是研究区地质灾害的主要驱动因子。     

利用卫星资料反演月平均近海面气温和湿度

为弥补广阔海面上气象参数的观测数据的不足,利用专用成像传感器SSM／I和红外辐射计AVHRR资料进行近海面气温和湿度的反演,首先分析与近海面气温和湿度关系比较密切的几个气象因子及其相关性,并采用神经网络建立近海面气温和湿度与它们之间的关系,利用训练好的网络模型反演月平均近海面气温和湿度,并与TAO和NDBC提供的浮标及观测站的实测数据进行比较,近海面气温和相对湿度的均方根差分别为0．87℃和3．73％。低纬度反演的结果精度较高,达到0．53℃（气温）和2．03％（相对湿度）;较大的误差（气温1．06℃、相对湿度3．85％）主要发生在近岸和高纬度区,因为近岸的地形比较复杂,并且很容易受陆地气候的影响;高纬度地区的气候变化比较剧烈,同时目前能得到的高纬度地区的实测资料比较少,这些因素都会影响反演结果的准确度。     

两种盐藻光合作用特性的比较

于1989年9－11月分别在中国科学院水生生物研究所和天津轻工部制盐研究所取得盐藻Dunaliellasp.HB558和Dunaliellasalina1009。这两个藻种的光合放氧-光强曲线，光系统Ⅰ、光系统Ⅱ活性-温度曲线及甘油产量的结果表明，其光合作用的光饱和点皆为220μmol／（m2·s），并可忍受40℃的温度；当温度为45℃时，D．sp．HB558的光合放氧明显受到抑制，光系统II活性下降，但对从D.salina1009则无影响;D.sp.HB558在10-40℃下的光合放氧速率及甘油产量都高于D.salina1009.培养这两种蕉的最适温度为30—35℃。     

High population connectivity and Pleistocene range expansion in the direct-developing plough shell Bullia rhodostoma along the South African coast

Pleistocene climatic and oceanographic changes have influenced the distribution of marine biodiversity in southern Africa. Most evidence, however, has been derived from rocky shore or demersal taxa; data on sandy shore species are limited, despite severe threats to many sandy beach ecosystems. To test the effects of past climatic changes on sandy shore species, we sampled 140 smooth plough shell Bullia rhodostoma individuals from eight localities and generated phylogeographic data derived from the mtDNA cytochrome c oxidase subunit 1 (COI) marker. Nuclear markers (ATPSα, ATPSβ, ANT, SRPS4, TBP, LTRS and ZMP) showed no sequence variation. Bullia rhodostoma exhibited shallow genetic differentiation (Φ_ST = 0.07, p < 0.05) across its range. Isolation-by-distance suggests a stepping-stone model of migration, which is expected given the species’ direct-development life-history strategy. Demographic reconstruction suggests a post-LGM (Last Glacial Maximum) range expansion, concordant with the signal of shallow genetic differentiation. Phylogeographic patterns obtained suggest that, during lower sea levels than current, B. rhodostoma could have been restricted to the South-West Coast, the central Agulhas Bioregion and probably also the East Coast. When climatic conditions changed and temperatures began to rise after the LGM, the species began a rapid westward range expansion from these refugial regions.     

星载微波ERS-1和多通道SSM/I观测海洋的相关性和随机粗糙面复合模型的数值模拟

欧洲遥感卫星（ERS）和美国防卫气象卫星计划（DMSP）空对地微波遥感是当今研究全球大气地表微波散射辐射和反演地球物理与水文参数的主要数据来源．本文研究了ERS－1散射计和SSM／I多通道辐射计在中国海域观测到的后向散射和热辐射数据,论证了同一地区同一时间段内ERS主动散射计和SSM／I被动辐射计观测数据的相关性．用海域主、被动遥感数据的比较,阐述了主、被动联合多通道分析方法有利于监视和分析复杂地表和海面在时间和空间尺度上的变化．用带泡沫散射层的双尺度随机粗糙面的复合模型计算后向散射和热发射,用以数值模拟ERS和SSM／I数据．并讨论了后向散射与热辐射数值模拟结果的相关性,以及与星载微波遥感器实际观测结果的比较．     

叠前偏移计算中多文件并行I/O技术

这里针对波动方程叠前深度偏移计算所涉及的数据,设计相应的数据文件格式,快速有效地从多文件海量数据中获取所需信息;根据不同的输入/输出数据,采用不同读写方式(串行/并行);解决了并行计算时的负载平衡以及计算中断后的数据恢复,充分提高了波动方程叠前深度偏移计算效率。