北京城市居民日常活动空间的社区分异

居民日常活动空间直接反映其对城市空间的利用状况及生活质量,从而得到地理学、规划学、社会学等领域的关注。中国城市在市场化转型、快速城市化等背景下,社会阶层分化与居住空间分异日益明显,城市社区无论在社会构成还是在建成环境上都呈现出显著的空间分异。基于对北京城市居民活动日志问卷调查数据,借助GIS可视化与空间分析方法,通过对北京城市不同类型社区居民日常活动的时空分布、活动空间形态及面积等特征的比较,揭示不同社区居民的日常活动空间的社区分异,试图将基于人口属性、设施供给的社区分异研究拓展到基于日常行为的居民对城市空间利用的社区分异。     

利用水位同震阶变资料反演汶川8级地震应力场变化

分析汶川地震的水位同震响应阶变发现,地震时应力场的调整与中国大陆板块的背景应力场受力状态基本一致,只是对华北和西南地区有所加强,对西北和东南有所减弱.可见,汶川地震释放积累的应力后,对于震后大陆的应力场变化有一定调整作用.     

Amalgamation of North China Craton with Alxa Block in the Late of Early Paleozoic: Evidengce from Sedmentary Sequences in the Niushou Mountain, Ningxia Hui Autonomous Region, NW China

华北与阿拉善两个古陆块是何时拼合在一起的,一直是地质界激烈争论的问题.本文报道了宁夏牛首山西南麓出露的泥盆纪与石炭纪地层波痕及斜层理等沉积构造和构造变形方面的新资料,结合前人近年来获得的区域上奥陶纪砂岩碎屑锆石年龄资料,推测华北与阿拉善两个古陆拼合发生在晚奥陶世至泥盆纪早期之间的某一地质时期.     

Prevalence and risk assessment of antibiotics in riverine estuarine waters of Larut and Sangga Besar River,Perak

Antibiotics released into the environment through anthropogenic activities exert selective pressure,driving bacteria towards increasing antimicrobial resistance.The prevalence of antibiotics and the ecological risks posed in the riverine estuarine of Larut River and Sangga Besar River,which included wastewater effluents from hospital,zoo,and poultry slaughterhouse sources were investigated.Solid phase extraction(SPE) followed by high-performance liquid chromatography tandem mass chromatography(HPLC-MS/MS) were used to extract and quantify the antibiotic residues from 22 antibiotics belonging to six major antibiotic classes(sulfonamide,macrolide,fluoroquinolone,phenicol,trimethoprim,and tetracycline).Sixteen antibiotic residues were detected with concentrations ranging from limit of detection(LOD) to 1 262.3 ng/L.Fluoroquinolones and macrolides were the most frequently detected compounds.Erythromycin,clarithromycin and ofloxacin detected in hospital and zoo effluents posed a high risk to algae while tetracycline had low to medium ecological risks toward all the relevant organisms from aquatic environments(algae,invertebrate Daphnia magna,and fish).     

Rising trend of relative sea level along the coast of East Asia

The rise or fall trend of the sea level along the coast of East Asia is estimated with different computational methods based on sea‐level data of longer time series collected from 45 tide gauge stations there. The results show that the relative sea level, on average, has been rising along the coast of the whole of East Asia from the early 1950s to the early 1990s. The regional change of sea‐level rise or fall is greater. The sea level along the coast of China, except along the Shandong Peninsula, is rising; the sea level along the coast of the southern islands of Japan and the southern Korean peninsula, as estimated by several methods, is mostly rising, but the rate of rise is very small. The difference between the results estimated in this study and the corresponding results of Barnett along the coast of East Asia is significant. This is mainly because the number of the stations selected by Barnett is relatively small, and the selected stations are concentrated at the southern and northern ends of the region, without data in the middle of the region. The effect of the estimating methods is smaller.     

麦秸秆加筋石灰固化盐渍土的破坏形态分析

土的破坏形态是其受力大小与状态的综合反映,也是其内部结构变化的宏观体现。对比分析了不同养护时间、布筋方式和围压下的盐渍土、麦秸秆加筋盐渍土、石灰固化土、麦秸秆加筋石灰固化土试样的三轴剪切破坏形态。结果显示:①盐渍土和麦秸秆加筋盐渍土均呈塑性破坏。其中,盐渍土呈典型的"鼓胀"破坏;受到加筋的约束,加筋土的横向变形小于盐渍土的。②养护前期,石灰同化土和麦秸秆加筋石灰固化土均呈塑性破坏;养护后期,均呈脆性破坏。麦秸秆加筋石灰同化土的破裂面较石灰固化土的不规则,没有类似石灰同化土的对称性破裂块。③低围压下,加筋土的约束力主要来自筋土间的摩阻力,土的破裂纹形态较高围压下的复杂。高围压下,约束力来自筋土摩阻力和围压的共同作用。④麦秸秆的加筋作用可有效地约束和阻止裂纹的发生和扩展。分区布筋时,土样的破坏主要发生于未加筋部位。麦秸秆和石灰共同加筋固化能有效地提高土的抗变形能力,是改善滨海盐渍土的一种可行的处理方法。     

中心式喷发火山岩三维地震刻画方法

基于火山岩溢流相的高连续强振幅和火山通道相的低连续弱振幅2种截然相反的地震反射特征,提出了振幅-方差体地震属性分级-拾取-融合技术刻画火山岩时空展布的解释新方法。具体流程是通过振幅分级显示,拾取强振幅刻画溢流相的空间展布;通过方差体分级,拾取高值部分刻画火山通道相的空间展布;最后将二者融合显示。通过渤海湾盆地莱州湾凹陷垦利6-A区块实例分析,表明该方法可以直观、有效地刻画火山岩的三维时空展布特征。研究成果有助于火山岩的三维刻画,可以广泛运用于与火山岩相关的含油气盆地。     

准噶尔盆地玛湖凹陷夏子街扇区三叠系百口泉组绿帘石分布特征及成因*

准噶尔盆地玛湖凹陷夏子街扇区三叠系百口泉组重矿物中绿帘石占绝对优势,且含量变化大。为了解研究区绿帘石的分布特征及其成因,利用重矿物、能谱及扫描电镜等资料,借助聚类分析和相关性分析等多元统计方法,对绿帘石的分布特征及成因进行了系统的研究。结果表明: (1)根据绿帘石含量可将研究区划分为绿帘石高值区、中值区和低值区;(2)绿帘石高值区位于扇三角洲前缘亚相,中值区和低值区主要位于扇三角洲平原亚相,且低值区比中值区更靠近物源;(3)绿帘石高值区不仅有岩浆绿帘石,自生绿帘石也普遍发育,因此绿帘石含量高;中值区绿帘石主要为岩浆绿帘石;低值区地层遭受了抬升剥蚀,溶蚀淋滤作用对搬运沉积的绿帘石破坏强烈,故显示低值。     

牡丹江－鸡西花岗岩类同位素地质年代学研究

牡丹江－鸡西一带有许多花岗岩类出露，其中具代表性的为柴河、石场、光复屯、岗子沟岩体等。过去人们一直将其认作元古代花岗岩体。作者采用单颗粒锆石逐层蒸发－沉积测年法，对区内包括上述岩体在内的花岗岩、花岗斑岩、混合岩及花岗质脉体，分别选其中锆石，进行年龄测定。结果表明：区内花岗岩类的侵位及混合岩化作用主要发生于２９０－２５０Ｍａ的华力西造山阶段，部分花岗岩可能形成于４８８－４０９Ｍａ的加里东期，而不形成于元古代；同时根据花岗岩和混合岩中获得的２８７１±８Ｍａ和１１３４±１４Ｍａ继承锆石的年龄数据，认为八面通杂岩两侧均存在前寒武纪变质基底。     

江汉平原长湖浮游植物初级生产力的季节性变化及其驱动因子

为探究长江中下游富营养化浅水湖泊的浮游植物初级生产力季节性演替特征及其驱动因子,本研究于2020年4月(春)、8月(夏)、10月(秋)及2021年1月(冬)对湖北长湖浮游植物进行采样调查,同时运用黑白瓶测氧法及VGPM模型估算法分别估算了其浮游植物生产力水平,并探究驱动初级生产力季节性变化的主要环境因子。结果显示,4个季节共鉴定出浮游植物194种,其中绿藻门(95种,49%)和硅藻门(40种,21%)居绝对优势地位;黑白瓶法测得浮游植物水柱总生产力(P_t)季节变化为:夏季((1841.24±345.93) mg C/(m²·d))>秋季((1324.14±208.34) mg C/(m²·d))>春季((847.50±247.72) mg C/(m²·d))>冬季((711.43±133.52) mg C/(m²·d)),其中M2站位在夏季采样时(2424.66 mg C/(m²·d))水柱总生产力最高;在垂直空间上,浮游植物总生产力(G...