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861.
This paper reports on recycling of industrial wastes (three pharmaceutical industrial sludges) into environmental friendly value-added materials. Stabilization/Solidification (S/S or bricks) process was applied to make a safer way for the utilization of pharmaceutical waste. The additives in this study include binders (cement, lime and bentonite) and strengthening material (pulverized fuel ash (PFA), silica fume and quarry dust) was used at different compositions. Bricks were cured for 28 days, and the following analysis-like compressive strength, leachability of heavy metals, mineralogical phase identity by X-ray diffraction (XRD) spectroscopy, Fourier transform infrared spectroscopy (FTIR) and thermal behaviour by thermogravimetric-differential thermal analysis (TG-DTA) had done. All the bricks were observed to achieve the standard compressive strength as required for construction according to BIS standards. Metal concentration in the leachate has reached the dischargeable limits according to Brazilian standards. Results of this study demonstrate that production of bricks is a promising and achievable productive use of pharmaceutical sludge.  相似文献   
862.
The European Economic Community Council Directive 80/779/EEC describes air quality limit values and guide values for sulfur dioxide and suspended particulates. However, article 10, paragraph 1 does not define well enough the reference method required, amongst others, for the gravimetric measurement of suspended particulates. It is explicity stated in article 10, paragraph 5 of the directive, that "the commission shall, in selected locations in the member states and in cooperation with the latter, carry out studies on the sampling...of suspended particulates. These studies shall be designed in particular to promote the harmonization of methods of sampling and analysis of these pollutants." Therefore, in a joint research program the Umweltbundesamt (grant #104 02263), the commission of European Communities (grant #84-B-6642-11-017-11-N) and the U.S. EPA (grant #2-432U-3580) funded the development of a reference dust sampler by the Fraunhofer-Institute of Toxicology and Aerosol Research (FhlTA, in Hannover, Federal Republic of Germany) in order: to study the particle size distribution of ambient air aerosol at a number of selected sites; to compare the results obtained with the reference dust sampler with those of particle samplers operated in Europe and the United States; to verify the applicability of wind tunnel results to sampling behaviour in the free atmosphere.  相似文献   
863.
864.
Photoadaptations of zooxanthellae living within the deep water coral Leptoseris fragilis taken from the Gulf of Aqaba (Red Sea) were studied. Specimens-collected in summer 1988 between 110 and 120 m depth —were transplanted to 70 and 160 m. At each depth individuals were exposed in their natural growth position (oral side facing the surface) or in a reverse growth position (oral side facing the bottom). After 1 yr of exposure the corals were collected and the zooxanthellae were isolated. As a function of the availability of light with depth and growth position several algal parameters showed changes which are related to photoadaptations. The relatively low density of zooxanthellae of 0.15x106 cellsxcm-2 at a natural growth depth of 116 m decreased to 0.0034x106 cellsxcm-2 (2%) at 160 m in specimens growing with a natural orientation. In corals with a downward-facing oral surface at the same depth (160 m) only degenerated algae could be observed. With respect to depth dependence the volume of the algae decreased from 728 m3 at 116 m to 406 m3 at a depth of 160 m and the content of pigments increased. The augmentation of peridinin per cell was low (two times at 160 m compared to 116 m). Chlorophyll a and in particular chlorophyll c 2 concentrations per cell were enhanced. Compared to natural amounts at 116 m, chl a was five times and chl c 2 eight times higher at 160 m. At all depths the chl c 2 content per cell was higher than for chl a. The formation of chl a/chl c 2 complexes as light harvestor is discussed. Light harvesting, with chl c 2 prevailing may be explained as a special type of chromatic adaptation of L. fragilis in a double sense: (1) in the habitat light short wavelengths predominate. This light can be directly absorbed with pigments such as chl a and chl c 2. (2) Host pigments absorb visible violet light and transform these wavelengths, less suitable for photosynthesis, into longer ones by means of autofluorescence. The emitted longer wavelengths fit the absorption maxima of the algal pigments. Thus the host supports photosynthesis of his symbionts. Corals exposed at 160 m depth with a downward facing oral surface were alive after 1 yr and the host wavelength transforming pigment system was still present, but zooxanthellae were absent or degenerated. The light field at 160 m seems therefore to be critical: the combined photoadaptations of host and symbionts, allowing photosynthesis under barren light conditions, seem to be exhausted. In L. fragilis the photoadaptive strategies of host and symbionts cooperate harmoniously. In addition, the adaptations are interlocked with the particular light situation of the habitat with respect to light quantity and quality. The cooperation of physical and organismic parameters examplifies how evolution and, in particular, coevolution has led to optimal fitness.  相似文献   
865.
D. Liang  S. Uye 《Marine Biology》1997,128(3):415-421
Population dynamics and production of the egg-carrying calanoid copepod Pseudodiaptomus marinus were studied for a year in Fukuyama Harbor, a eutrophic inlet of the Inland Sea of Japan. This species was perennial, with a large numerical peak in June and small peaks in September/October and November/December. During the study period, at least 11 generations could be detected. For each generation, the stage-specific survival from egg to Copepodite Stage (C) V was determined; it was very high during early life stages (egg to NIII), and gradually decreased beyond. On average, 94% of eggs recruited into NIII, which is strongly contrasted with very high (>ca. 90%) mortality during the corresponding stages for free-spawning copepods, i.e. Acartia omorii, Centropages abdominalis and Paracalans sp. This demonstrates that the egg-carrying strategy has a great advantage to reduce mortality in egg stage. The biomass of this species showed marked seasonal variations largely in parallel with numerical abundance. The instantaneous somatic growth rate increased linearly with temperature. The population production rate was estimated as the sum of somatic growth of larval stages and egg production of adult females; the annual integration was 51.0 mg C m−3 yr−1 or 0.38 g C m−2 yr−1. Received: 11 November 1996 / Accepted: 7 December 1996  相似文献   
866.
We show the potentiality of coupling together different compound-specific isotopic analyses in a laboratory experiment, where 13C-depleted leaf litter was incubated on a 13C-enriched soil. The aim of our study was to identify the soil compounds where the C derived from three different litter species is retained. Three 13C-depleted leaf litter (Liquidambar styraciflua L., Cercis canadensis L. and Pinus taeda L., δ13CvsPDB ≈ ?43‰), differing in their degradability, were incubated on a C4 soil (δ13CvsPDB ≈ ?18‰) under laboratory-controlled conditions for 8 months. At harvest, compound-specific isotope analyses were performed on different classes of soil compounds [i.e. phospholipids fatty acids (PLFAs), n-alkanes and soil pyrolysis products]. Linoleic acid (PLFA 18:2ω6,9) was found to be very depleted in 13C (δ13CvsPDB ≈ from ?38 to ?42‰) compared to all other PLFAs (δ13CvsPDB ≈ from ?14 to ?35‰). Because of this, fungi were identified as the first among microbes to use the litter as source of C. Among n-alkanes, long-chain (C27–C31) n-alkanes were the only to have a depleted δ13C. This is an indication that not all of the C derived from litter in the soil was transformed by microbes. The depletion in 13C was also found in different classes of pyrolysis products, suggesting that the litter-derived C is incorporated in less or more chemically stable compounds, even only after 8 months decomposition.  相似文献   
867.
ABSTRACT: Land application of organic soil amendments can increase runoff concentrations of metals such as Fe and Zn, metalbids such as B and As, and non-metals such as P and S that have the potential for causing adverse environmental impacts. Aluminum sulfate, or alum (Al2(SO4)3*(14H2O), can reduce concentrations of some materials in runoff from sites treated with organic amendments. The objectives of this study were to (a) quantify concentrations of selected constituents (Al, As, B, Ca, Cd, Co, Fe, K, Mg, Mn, Mo, Na, P, Pb, 5, Se, Ti, and Zn) in runoff from plots treated with horse manure (mixed with stall bedding) and municipal sludge, (b) assess runoff quality effects of alum addition to those treatments, and (c) determine time variations in concentrations of the constituents. Horse manure and municipal sludge were applied to twelve 2.4 by 6.1 m fescue plots (six each for the manure and sludge). Alum was added to three of the manure-treated and three of the sludge-treated plots. Simulated rainfall (64 mm/h) was applied to the 12 treated plots and to three control (no treatment) plots. The first 0.5 h runoff was sampled and analyzed for the constituents described above. Addition of manure or sludge had no effect on runoff concentrations of the majority of constituents. In some cases (e.g., Al, As, Fe, Zn), however, concentrations were near or in excess of threshold values recommended for marine wildlife protection. Alum addition increased runoff of Al, Ca, K, and 5, due likely to its composition and by the addition of lime to counteract the acidity of alum. Concentration decreases of more than 50 percent were noted for P for the horse manure treatment. No alum effect was detected for P in runoff from the sludge-treated plots, possibly due to relatively stable P forms in the sludge. Runoff concentrations of Al, As, Fe, K, Mn, and P followed an approximately first-order decline with respect to time. Runoff concentrations of Ca and 5, however, peaked during the second runoff sample (four minutes following initiation of runoff), suggesting that differences in mobility and/or transport mechanisms exist among the materials investigated.  相似文献   
868.
869.
870.
Turton D  Turton P 《Disasters》1984,8(3):178-189
Based upon two recent periods of fieldwork among a spontaneously resettled population of cattle herders in southwestern Ethiopia, this paper is an attempt to illustrate, by a particular case, the general proposition that external aid, if it is not to be counter-productive, must meet people's needs as they themselves define them. The people in question, the Mursi, have experienced, since 1970, their worst period of drought and hunger in living memory. They have responded to this experience with resilience and inventiveness and largely without external assistance. The paper concentrates on a recent, drought induced, migration of Mursi to higher land, outside their traditional territory, and shows how the migrants are adapting to a new way of life which brings them into direct conflict with some of their most cherished cultural traditions.  相似文献   
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