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11.
This study investigated the adsorption and precipitation of phosphate by blast furnace slag (BFS) separately.

In order to evaluate the adsorption capacity of BFS, BFS was treated before its use by acid. The authors aim to develop a new porous carrier to adsorb simultaneously ammonium and phosphate from seawater under eutrophic conditions. The current paper deals with a promising new approach to improve the utilization of some industrial solid wastes such as BFS and zeolite synthesized from fly ash [ZFA(Fe)] by their solidification to cylindrical porous carriers using a hydrothermal hot-pressing (HHP) method.

Attempts to produce porous carriers using an arranged HHP method with different porosities (24%, 40% and 52% (v/v)) were carried out. Physical properties of carriers such as porosity, compressive strength and height have been investigated. Laboratory studies showed strong evidence that the porous carrier was very selective towards phosphate and ammonium. The results demonstrated the role of porosity in enhancing phosphate and ammonium adsorption by the increase of the surface area per weight. The estimates of the parameters and the correlation coefficients according to the Freundlich equations revealed that adsorption was related to the porosity of carriers and phosphate and ammonium were adsorbed well on the carriers having large porosity.

The results suggested that developing carrier with high porosity was a promising way to enhance nutrients adsorption.  相似文献   

12.
We present a 2-10 keV ASCA observation of the field around the soft gamma repeater SGR 1627-41. A quiescent X-ray source, whose position is consistent both with that of a recently discovered BeppoSAX X-ray source and with the Interplanetary Network localization for this soft gamma repeater, was detected in this observation. In 2-10 keV X-rays, the spectrum of the X-ray source may be fit equally well by a power-law, blackbody, or bremsstrahlung function, with unabsorbed flux approximately 5x10-12 ergs cm-2 s-1. We do not confirm a continuation of a fading trend in the flux, and we find no evidence for periodicity, both of which were noted in the earlier BeppoSAX observations.  相似文献   
13.
The Monsoon Experiment is the core of the GARP Monsoon Subprogramme, which is a major international effort to achieve a better understanding of the Planetary monsoon circulation, the major seasonal perturbation of the general circulation of the atmosphere and the influence of the annual cycle of precipitation associated with the monsoon on the agriculture of the many populous nations of the region.This is a summary report of the International MONEX Planning Meetings, which were held in Yerevan, USSR, March 1973; Singapore, November 1974; New Delhi, March 1977; and Kuala Lumpur, February 1978.MONEX represents a group of observational studies during the First GARP Global Experiment (FGGE) over the South China Sea (December 1978), Arabian Sea (May–June 1979), and Bay of Bengal (July–August 1979). These periods will permit study of most of the significant aspects of the winter and summer monsoons. This is elaborated on in Sections 2 and 3.  相似文献   
14.
Seasonal variability regarding the nature of precipitation and the activity of cumulus convection during the 1991 Meiyu season of Changjiang-Huaihe River Basin(Jianghuai)has been investigated by calculating apparent heat source/apparent moisture sink and analyzing TBB(cloud-top blackody radiation temperature)data.It is found that three periods of strong ascending motion during the Meiyu season lead to three episodes of heavy rain,and the latent heat due to the precipitation is of the sole heat source of the atmosphere.The nature of precipitation shows distinct seasonal variability,from frontal precipitation of the first episode to the extremely strong convective precipitation of the third episode.TBB field of East Asia may well reflect not only the intensity of convection and rainfall,but also the movement of rain belt and convection belt.In the whole Meiyu season.convection belt mainly stays in Jianghuai.but may shift within the domain of East Asia.Its locating in Jianghuai or not determines the maintenance or break of Meiyu.In the third episode,the narrow convection belt over Jianghuai is mainly caused by southwest monsoon which takes moist and convective atmosphere from tropical ocean.  相似文献   
15.
This paper presents a case study that assessed spatial variations in the tectonic uplift rates of beach deposits in the relict Kujukuri strand plain, situated on the northeastern coast of the Boso Peninsula, eastern Japan. The southern Boso Peninsula is tilted downward to the northeast due to plate subduction along the Sagami Trough. However, the cause of the northeastern coast uplift creating the relict strand plain is unclear, due to the absence of a Holocene raised marine terrace sequence. Elevations and ages of beach deposits were collected from drilled cores and ground-penetrating radar profiles along three shore-normal sections in the southern Kujukuri strand plain. From this, alongshore variations in the relative sea level since the mid-Holocene could be seen. These corresponded to north-to-northeast downward tilting at a rate of 0.4 m/ka for an interval 10 km and are concordant with the longer term tilting of the last interglacial marine terrace surrounding the plain. Although it is difficult to assess shore-normal variations of uplift based on the present dataset, the recognized tilting apparently continues to the tilting of the southern Boso Peninsula, implying the Sagami Trough probably affects the uplift of the Kujukuri coast.  相似文献   
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18.
ASCA has observed two Soft Gamma-ray burst Repeaters (SGRs) among three known. This is a short report of the two SGRs, 1806–20 and 0526–66(N49). The observed X-ray characteristics favor a spin-powered system for SGR1806-20 and no ASCA detection of the hard X-ray component from SGR0526–66 suggests a very soft spectrum of the ROSAT HRI X-ray point source.  相似文献   
19.
Based on calculations of data from FGGE Level III b, a discussion is made of the energy balance in the 40-50 day periodic oscillation over the Asian monsoon region during the 1979 summer. It is found that the main source of 40-50 day periodic perturbation is the monsoon region extending from central South Asia to Southeast Asia. In the upper layer over the North Pacific subtropical area (10-20oN, 150oE-150oW) pres-sure work turns into kinetic energy that maintains 40-50 day periodic perturbation associated with the variation in position and intensity of the mid-Pacific trough. The mean energy budget in the three-dimensional space (0-30oE, 30oE-150oW, 100-1000 hPa) indicates that the 40-50 day periodic perturbation transports kinetic energy to a seasonal mean and a transient perturbation wind field.  相似文献   
20.
Fission-track (FT) thermochronologic analysis was performed on zircon separates from rocks in and around the Nojima fault, which was activated during the 1995 Kobe earthquake. Samples were collected from the University Group 500 m (UG-500) borehole and nearby outcrops. FT lengths in zircons from localities > 25 m away from the fault plane as well as one 0.1 m away from the fault in the footwall are characterized by concordant mean values of  10–11 μm and unimodal distributions with negative skewness, which showed no signs of appreciable reduction in FT length. In contrast, those adjacent (< 3 m) to the fault at depths on the hanging wall side showed significantly reduced mean track lengths of  6–8 μm and distributions having a peak around 6–7 μm with rather positive skewness. The former pattern is interpreted to reflect cooling through the zircon partial annealing zone (ZPAZ), without later, partial thermal overprints. The latter indicates substantial track shortening due probably to secondary heating by a thermal event(s) that locally perturbed the geothermal structure. Modeled zircon FT length and age data of partially annealed samples from the UG-500 borehole revealed a cooling episode in the ZPAZ that started at  4 Ma within  3 m from the fault plane, whereas those from the Geological Survey of Japan 750 m borehole record cooling started at  31–38 Ma within  25 m from the fault. On the basis of one-dimensional heat conduction modeling as well as the consistency between the degree of FT annealing and the degree of deformation/alteration of borehole rocks, these cooling ages in both boreholes are interpreted as consequences of ancient thermal overprints by heat transfer or dispersion via fluids in the fault zone. Together with the zircon FT data of a pseudotachylyte layer recently analyzed, it is suggested that the present Nojima fault system was reactivated in the Middle Quaternary from an ancient fault initiated at  56 Ma at mid-crustal depths. Also shown is a temporal/spatial variation in terms of the thermal anomalies recorded in the fault rocks, implying heterogeneity of hot fluid flows in the fault zone.  相似文献   
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