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21.
Aerosol particles were collected in the situation of the widespread dust suspension on 21 February 1991 at Qira in the southern edge of the Taklamakan Desert, western China. The collected particles were examined by a transmission electron microscope equipped with an energy-dispersive X-ray (EDX) analyzer in order to obtain the size and elemental composition of individual mineral particles.On the basis of EDX analyses for 386 particles, mineral particles were present in high number fractions (>99%) of particles in the radius range of 0.1–4 μm. Particles mainly composed of silicates comprised 76% of mineral particles. “Ca-rich” particles were detected in 7% of all the particles. Ca in the particles would be present not only as CaCO3 but also as an internal mixture of CaCO3 and CaSO4. Particles containing halite (NaCl) were detected in number proportions of about 10% and were mainly present in the radius range of 0.5 μm. Some halite particles would be modified by chemical reactions with sulfuric acid.  相似文献   
22.
The performance of a garbage disposal system to solubilize and mineralize food wastes through biological solubilization was evaluated through the examination of the effects of operational conditions like water supply volume, water supply frequency and aeration on the amount of waste solubilized, mineralized and accumulated in the reactor. The biological solubilization process consisted of a solubilization reactor and a circulation tank. Food waste and fresh water were supplied into the solubilization reactor with support media. Wastewater from the solubilization reactor was discharged to the circulation tank and water in the circulation tank was periodically pumped back to the solubilization reactor. In case of the total food waste loading of 16 kg m(3-1) d(-1), little carbon (0-5.7%) accumulated in the reactor as long as the system was kept under aerobic condition through large volume of water supply (higher than 3.5 lh(-1)) or applying aeration in the circulation tank. However, 42% of the loaded carbon accumulated under anaerobic condition in low water supply (less than 1.8 lh(-1)). The rest of the waste was either solubilized or mineralized. The aeration in the circulation tank, therefore, was effective to provide similar solubilization and mineralization as the large volume of water supply. However, frequency of feeding at the large volume of water supply had no significant effect on the amount of waste solubilization and mineralization.  相似文献   
23.
The state of mixture of light-absorbing carbonaceous particles was investigated in relation to light absorption properties using electron microscopic examinations, black carbon (BC) analyses of quartz filter by thermal/optical reflectance (TOR) method, measurements with two continuous light-absorbing photometers at a suburban site of Tsukuba, about 60 km northeast of Tokyo. The volume fraction of water-soluble material (?) in individual particles is important for assessing particulate light-absorbing and/or scattering of atmospheric aerosols. The values of ? in BC particles were evaluated by electron micrographs before and after dialysis (extraction) of water-soluble material. The mass absorption coefficient (MAC in units of m2 g?1) tended to increase with increasing the average ? in BC particles with the radius range of 0.05–0.5 μm. Thus, our results indicate that coatings of water-soluble material around BC particles can enhance the absorption of solar radiation. Moreover, the single scattering albedo (SSA) will increase because a large amount of coating material will scatter more light.  相似文献   
24.
Lead can be recovered from funnel glass of waste cathode ray tubes via reduction melting. While low-temperature melting is necessary for reduced energy consumption, previously proposed methods required high melting temperatures (1400 °C) for the reduction melting. In this study, the reduction melting of the funnel glass was performed at 900–1000 °C using a lab-scale reactor with varying concentrations of Na2CO3 at different melting temperatures and melting times. The optimum Na2CO3 dosage and melting temperature for efficient lead recovery was 0.5 g per 1 g of the funnel glass and 1000 °C respectively. By the reduction melting with the mentioned conditions, 92% of the lead in the funnel glass was recovered in 60 min. However, further lead recovery was difficult because the rate of the lead recovery decreased as with the recovery of increasing quantity of the lead from the glass. Thus, the lead remaining in the glass after the reduction melting was extracted with 1 M HCl, and the lead recovery improved to 98%.  相似文献   
25.
26.
Social insects provide an intriguing model system in chronobiology. Typically, an egg-laying queen exhibits arrhythmicity in activity while foraging worker has clear rhythmicity. In the queenless ant, Diacamma sp., from Japan, colony members lack morphological caste, and reproductive differentiation occurs as a consequence of dominance hierarchy formation. Their specialized dominance interaction “gemmae mutilation”, provide us a fascinating model system to investigate the effect of social dominance on rhythmic ontogeny. Measurement of individual rhythms revealed that they have clear circadian rhythm at eclosion but it is diminished by social mutilation of gemmae. Moreover, unlike highly eusocial species, mated egg-layer (i.e., gamergate) possessed a circadian rhythm even after mating in Diacamma. Measurement of colony-level rhythms revealed that gemmae mutilations are performed in the limited time of the day, but foraging occurs around-the-clock. The above finding is a novel form of temporal organization in social insects, providing a new insight in morphologically casteless species. We discuss the causes and consequences of rhythmic variability in social organization.  相似文献   
27.
Uptake properties of Ni2+ were examined for unmilled and milled paper sludge calcined at various temperatures to develop a new usage of waste paper sludge. Since paper sludge mainly consists of cellulose ([C6H(10)O5]n) fibers, calcite (CaCO3), kaolinite (Al2Si2O5(OH)4) and talc (Mg3Si(4)O(10)(OH)2), amorphous and crystalline CaO(MgO)-Al(2)O(3)-SiO(2) compounds are formed by calcining paper sludge. Wet and dry milling treatments were performed to accelerate solid-state reaction to form the above mentioned target compounds. The crystalline phases originally present decompose at increasing calcining temperature (up to 800 degrees C) in the order cellulose 相似文献   
28.
基于营养系统的灾害避难所规划的概念模型   总被引:2,自引:0,他引:2  
通过对比中、日、美3国的灾害避难所及其规划设计指导手册,总结了灾害避难所的基本类型和避难所规划的空间尺度(范围).从营养系统的角度给出了避难所规划的3个大类及8个实施标准,并以此为基础,提出了灾害避难所规划或评价的3个基本模式.  相似文献   
29.
The goal of integrated disaster risk management is to promote an overall improvement in the quality of safety and security in a region, city or community at disaster risk. This paper presents the case for a thorough overhaul of the institutional component of integrated disaster risk management. A review of disaster management institutions in the United States indicates significant weaknesses in their ability to contribute effectively to the implementation of integrated disaster risk management. Our analysis and findings identify eight key elements for the design of dynamic new disaster management institutions. Six specific approaches are suggested for incorporating the identified key elements in building new institutions that would have significant potential for enhancing the effective implementation of integrated disaster risk management. We have developed a possible blueprint for effective design and construction of efficient, sustainable and functional disaster management institutions.  相似文献   
30.
Experience-dependent tactics of males trying to gain access to females were examined in the beetle Gnatocerus cornutus, which engages in male–male fighting for mates. In male fights, subsequent behavior is modified by winning and losing experiences. Males, therefore, may choose between several behavioral tactics to obtain a mate, based on his previous fighting experience. In G. cornutus, we examined for how long aggressive behaviors were modified by experiences of winning or losing, i.e., the duration of the prior experience effect. Losing decreased a male's frequency of fighting for 4 days, and few defeated males fought any male regardless of the opponent's size. By the fifth day, this effect disappeared. No modulation of male behavior due to winning was observed. Furthermore, the experience of losing not only decreased a male's aggressiveness but also switched the male behavior from fighting to dispersal from the fight site to another site. In future, it is necessary to clarify why the optimal term of the losing experience is 4 days in this beetle.  相似文献   
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