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We have observed the energetic binary Cygnus X-3 in both quiescent and flaring states between 4 and 16 μm using the ISO satellite. We find that the quiescent source shows the thermal free–free spectrum typical of a hot, fast stellar wind, such as from a massive helium star. The quiescent mass-loss rate arising from a spherically symmetric, non-accelerating wind is found to be in the range (0.4–2.9)×10−4 M yr−1, consistent with other infrared and radio observations, but considerably larger than the 10−5 M yr−1 deduced from both the orbital change and the X-ray column density. There is rapid, large-amplitude flaring at 4.5 and 11.5 μm at the same time as enhanced radio and X-ray activity, with the infrared spectrum apparently becoming flatter in the flaring state. We believe that non-thermal processes are operating, perhaps along with enhanced thermal emission.  相似文献   
3.
《山西地震综合数据处理系统》是遵循《国家地震局数据库技术规范》,以PDP-11/23~+小型机与IBM/PC联机为硬件支撑,以网状型数据库为核心,含前期处理、库管理、数据检索、科学计算、分析会商5个子系统的较大型应用软件系统。具有对数据进行收集、录入、预处理、存储、管理、加工及应用等功能。整个系统通过总控菜单程序实现了异种机间上百个模块的调度,使查询-处理一体化。该系统把地震数据库、日常监测数据处理、专家地震预报系统有机地衔接于一体,可直接服务于地震科研和震情会商。该系统的建设是山西省重大科技攻关项目,也是国家地震局的合同制项目。  相似文献   
4.
运城盆地11 kaBP以来气候环境变迁与湖面波动   总被引:7,自引:0,他引:7  
通过黄土区湖泊沉积研究来恢复古气候、古环境,是对黄土区古气候、古环境研究的补充和检验。通过山西运城盆地硝地湖泊沉积物的多环境代用指标分析,结合史料记载,探讨了该地区11kaBP以来古气候演化和湖面波动的历史。结果表明,该地区存在YD(Younger Dryas)事件,进入全新世后气候有显著的趋势,最高湿润度发生在7.88-5.15和5kaBP后,气候逐渐变干,湖面波动与气候波动相关,全新世早期湖面开始上升,湖泊扩张,5kaBP后湖泊萎缩,盐类结晶析出。  相似文献   
5.
A. Coradini  G. Magni 《Icarus》1984,59(3):376-391
A detailed computation on the equilibrium structure of an accretion disk around Saturn from which the regular satellites presumably originated is reported. Such a disk is the predecessor of the self-dissipating disk that is formed when the mass infall stops (Cassen and Moosman, 1981, Icarus48, 353–376). When determining the disk structure local energy balance was assumed. Convention was taken into account by introducing local energy dissipation and, in an approximate manner, sonic convection. Changes in the disk structure were investigated by varying the free parameters, i.e., the external flux from both the protosun and the protoplanet, the abundance of dust and the strength of turbulence. It has been verified that the external energy flux does not play an important role in the evolution of the disk structure. Models characterized by either longer times (?3 103 year) or a noticeable depletion of condensable elements (10?2 times less than the solar value) have a total mass of the order of 0.34?0.1 times the mass of the regular satellites increased by the mass of the light elements. Low turbulence models (Reynolds critical number Re1 = 150) are characterized approximately by a total mass twice as large the mass of the regular satellites. All the studied models present a temperature distribution that allows the condensation of iron, silicate, and, in the outer regions, ice grains. All models but the one with 10?2 of the solar value of condensable elements are characterized by a wide convective region that contains the formation zone of the regular satellites.  相似文献   
6.
Integrated hydrological models are usually calibrated against observations of river discharge and piezometric head in groundwater aquifers. Calibration of such models against spatially distributed observations of river water level can potentially improve their reliability and predictive skill. However, traditional river gauging stations are normally spaced too far apart to capture spatial patterns in the water surface, whereas spaceborne observations have limited spatial and temporal resolution. Unmanned aerial vehicles can retrieve river water level measurements, providing (a) high spatial resolution; (b) spatially continuous profiles along or across the water body, and (c) flexible timing of sampling. A semisynthetic study was conducted to analyse the value of the new unmanned aerial vehicle‐borne datatype for improving hydrological models, in particular estimates of groundwater–surface water (GW–SW) interaction. Mølleåen River (Denmark) and its catchment were simulated using an integrated hydrological model (MIKE 11–MIKE SHE). Calibration against distributed surface water levels using the Differential Evolution Adaptive Metropolis algorithm demonstrated a significant improvement in estimating spatial patterns and time series of GW–SW interaction. After water level calibration, the sharpness of the estimates of GW–SW time series improves by ~50% and root mean square error decreases by ~75% compared with those of a model calibrated against discharge only.  相似文献   
7.
This paper introduces a unique industrial configuration that has emerged in Beijing, where three economic clusters in the biomedical industry, originally established as industrial/research parks, have developed parallel to each other. This configuration of multiple co-located clusters of the same industry, which has not been discussed before, raises the question of whether the industrial/research parks are competing for the same resources, or whether they are complementary to each other and can collectively be viewed as a new type of industrial configuration. The paper conceptualizes a framework of multiple clusters in mega-city regions that distinguishes between collaborating and competing clusters and presents initial empirical evidence for the Beijing case. As such, this research aims to unravel the phenomenon of multiple clusters in mega-city regions and to understand the complex spatial interrelationships that exist within and beyond multiple co-located clusters in the same industry.  相似文献   
8.
New UBV-photoelectric observations of the well-known massive X-ray binary system Cyg X-1/V 1357 Cyg are obtained near the primary minimum. The detailed analysis of these observations confirms the existence of additional blue radiation which appears as a narrow peak with an amplitude of 0.01–0.02 mag near phase 0.00 on the light curve (the superior conjunction of the relativistic component), firstly detected by Lyuty (1985). This emission does not appear at every orbital cycle. The appearance of this narrow peak of additional blue radiation on the light curve of Cyg X-1 can be explained as the radiation of relativistic electrons in the disturbed magnetic field of the optical star in frames of the model proposed by Ikhsanov and Fabrika (1990).  相似文献   
9.
快速城市化进程改变了城市地区原有下垫面,不透水层面积增加,暴雨期间汇流时间缩短,洪峰流量加大,进而导致城市内涝加剧,严重影响城市的防洪安全.本研究以广州市南沙区万顷沙网河区为研究对象,基于水量平衡的调蓄演算方法,对研究区域蓄排设施的规模进行分析;构建MIKE11一维网河模型,对涝区水情进行模拟,校核排涝工程规模,并对工...  相似文献   
10.
本文研究了以磷酸三丁酯为固定相,大孔聚乙烯苯(X-5型)为担体的浸渍树脂、垂直型反相色谱柱,对铀分离富集的基本性能,以及铀(Ⅳ)-间硝基苯基萤光酮(m-NPF)一氨三乙酸(NTA)-吐温-80显色体系的反应条件,提出了TBP(X-5)分离,m-NPF-NTA-吐温-80光度法测定铀,经标准样品验证,结果满意。  相似文献   
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