地铁施工对济南白泉泉群流量的影响

为研究地铁建设对济南白泉泉群的影响，在综合分析白泉泉域地质、水文地质条件的基础上，假定研究区岩溶强径流带位置及水力性质，利用FEFLOW软件建立地下水流数值模型。以规划地铁M1号线为研究对象，分析了济南东站、梁王站、梁王东站分别施工及3个站同时施工4种情景下，采用施工降水或施工降水+人工回灌两种施工方式对白泉泉群流量的影响。结果表明：单独采用施工降水的施工方式使得白泉泉群流量衰减，其中3个站同时施工对泉流量的影响最大，泉流量最大衰减达5.48%；各站分别施工时，济南东站对泉流量影响最大，泉流量较未施工时减少了0.043×10⁴ m³/d。采用施工降水+人工回灌的施工方式，能够有效缓解泉流量的衰减，各车站施工时的泉流量衰减由仅施工降水时的2.26%~5.48%降低至0.08%~1.21%。岩溶强径流带有利于地下水形成优势径流，促进白泉泉群补给，一定程度上缓解因地铁施工引起的泉流量衰减。     

30 m global impervious surface area dynamics and urban expansion pattern observed by Landsat satellites: From 1972 to 2019

Using more than three million Landsat satellite images, this research developed the first global impervious surface area (GISA) dataset from 1972 to 2019. Based on 120,777 independent and random reference sites from 270 cities all over the world, the omission error, commission error, and F-score of GISA are 5.16%, 0.82%, and 0.954, respectively. Compared to the existing global datasets, the merits of GISA include: (1) It provided the global ISA maps before the year of 1985, and showed the longest time span (1972–2019) and the highest accuracy (in terms of a large number of randomly selected and third-party validation sample sets); (2) it presented a new global ISA mapping method including a semi-automatic global sample collection, a locally adaptive classification strategy, and a spatio-temporal post-processing procedure; and (3) it extracted ISA from the whole global land area (not from an urban mask) and hence reduced the underestimation. Moreover, on the basis of GISA, the long time series global urban expansion pattern (GUEP) has been calculated for the first time, and the pattern of continents and representative countries were analyzed. The two new datasets (GISA and GUEP) produced in this study can contribute to further understanding on the human’s utilization and reformation to nature during the past half century, and can be freely download from http://irsip.whu.edu.cn/resources/dataweb.php.

     

板块绝对运动及地幔热对流

本文以板块绝对运动AM1-2模型为边界条件探讨了不同的瑞利数下地幔热对流模型.结果表明,瑞利数小于10000（529.41）时,地幔对流呈现以板块驱动图式,运动的极型场和环型场由板块运动激发,两种场占有差不多相同的功率.当瑞利数增加到接近或略超过最低临界值时（约1.5倍）,对流呈现出复杂状态:1.板块运动速率小于下伏地幔对流速率;2.区域性的双层对流环出现;3.对流谱成分发生变化;4.环型场仅在地幔很浅的区域中起作用,而在地幔深部对流图式中影响很小.     

冀西北长城纪宣龙式铁矿层中微体植物化石的发现及其意义

本文研究的是笔者等在冀西北长城系串岭沟组宣龙式铁矿层中发现的微体植物化石,这些化石都保存在铁质叠层石(肾状赤铁矿)和铁质核形石(鲕状赤铁矿)的基本层中。微化石以丝状体为主,部分为球状体。归属于原核生物蓝藻门颤藻科的两个属和色球藻科的一个属。化石层同位素年龄约在1800—1757Ma。这些化石与北美冈弗林特组微化石比较,既有些相似,又有些区别。该化石的发现为研究铁矿的成因,指示沉积环境及层位对比都很有意义。     

论四川盆地三叠系地下水水文地质条件

四川盆地三叠系地下水可划分出碎屑岩孔隙裂隙和碳酸盐岩岩溶裂隙两大储集类型。按此处构造开启程度和埋深条件等的不同,下中三叠统地下水有沉积变质水和渗入淋滤水两种基本成因类型,水动力特征各异。沉积变质水处于深埋封闭条件,受地静压力驱动控制;渗入淋滤水分布于背斜露头区和浅部地区,受静水压力驱动控制。并由此控制了盆地三叠系盐类的保存条件。     

Effects of dynamic shear strength and time-histories stress analysis on newmark sliding block analyses

A simplified procedure for evaluating aseismic stability of slope subjected to earthquake shaking, in which the effect of dynamic shear strength and time-history stress on the yielding angular acceleration of sliding block is taken into account, is presented. The fundamental feature of this procedure is the dynamic shear strength. The numerical computations are performed by using the proposed method. It is shown that the computed sliding displacement for a given core dam, with either method of dynamic shear strength properly considered, is more rational compared with the conventional computational results based on static shear strength.     

汽车底盘技术在HGY-1500型钻机中的应用

在HGY-1500型钻机的设计中应用汽车底盘技术，选用汽车变速器、离合器等零部件；钻机分动箱采用斜齿圆柱齿轮传动，使用接合套式换挡装置进行换挡，提高了钻机工作的可靠性，降低了生产成本，减轻了钻机质量，操作轻松、方便。     

四川盆地地下卤水资源优势及综合开发前景

四川盆地地下卤水自震旦系至白垩系各层系皆有分布。卤水具有分布广泛、资源丰富、品质优异、高承压及气卤同产等优势特点,是四川得天独厚的液态矿产资源。卤水中含有K+、Br-I、-、B3+、Li+、Sr2+、Rb+等多种有用组分,皆为国家紧缺和紧俏物质,其含量多数可达工业开采品位,为优质化工原料水,经济价值极高,综合开发利用前景广阔。     

加固含水平软弱层高陡边坡预应力锚索倾角的取值范围

用直线和曲线滑面两种模型，模拟预应力锚索加固含有水平软弱层的高陡边坡的潜在滑动面，通过对锚索加固的力学机理分析来阐述预应力在滑动面主滑方向上产生分力的原因。从锚索受力角度上对锚索倾角的取值范围进行探讨，结合实际造孔过程有不同程度的孔斜或弯曲以及获取较好的锚固灌浆效果，就仰角锚固和俯角锚固两种锚固条件分别得出锚索倾角的取值范围，并以此来判定锚索的预应力是否会在滑动面走向方向上产生不利于坡体稳定的下滑力。     

松溪县域城镇体系发展研究

城镇体系建设是当今加快城市化进程的重要组成部分。本文通过对松溪县域城镇现状的调查,从城镇体系的等级规模结构、空间布局结构、职能结构3个方面剖析其发展中存在的一些问题。从建设社会主义新农村、改善人居环境的角度出发,提出相应的发展思路和建议,为松溪县“十一五”期间制定城镇发展战略提供一定的参考。