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21.
The phylogenetic relationships among all living families of sea spiders (Arthropoda: Pycnogonida) are investigated using nearly complete 18S rRNA sequences from 57 ingroup species and five chelicerates under the Bayesian and maximum likelihood methods. Monophyly of Colossendeidae, Pycnogonidae, Phoxichilidiidae, Endeidae and Pallenopsidae is consistently supported. However, the genera formerly classified in the family Ammotheidae are split up into two distantly related groups. The genera Ascorhynchus and Eurycyde (here recognized as Ascorhynchidae) are possibly an early offshoot of sea spiders, whereas other ammotheids constitute a robust terminal clade with Pallenopsidae, Phoxichilidiidae and Endeidae. This topology also opposes the prevalent assumption of successive losses and simplification of three kinds of cephalic appendages like in a previous cladistic analysis. At least three independent losses are suggested for palps by the inferred topology, and both chelifores and female ovigers may have been lost twice. Our knowledge of early ontogeny and internal anatomy is more congruent with the present 18S rRNA data. The families Callipallenidae and Nymphonidae with unique “attaching larvae” are grouped together in present molecular trees, suggesting that extended paternal care of offspring evolved only once in Pycnogonida. Confident clustering of Pycnogonidae and Rhynchothoracidae indicates that the number of female genital pores is an evolutionary conservative character.  相似文献   
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A limited amount of information exists regarding the relationship between the chemical form of copper and the formation of chlorinated aromatics in fly ash. To understand the effects of the various forms of copper on the formation of chlorinated aromatics in real fly ash, we determined the chemical forms of copper present in various types of real fly ash using X-ray absorption near edge structure (XANES) and evaluated the relationship between the chemical forms of copper and the formation of chlorinated aromatics. Copper chloride hydroxide (CuCl2 x 3Cu(OH)2) and cuprous chloride (CuCl) were the predominant copper species found in real fly ash. Although pure cupric chloride (CuCl2) is known to be the most active catalyst for the formation of chlorinated aromatics under experimental conditions with synthetic fly ash, CuCl2 was not found in every real fly ash sample. The amount of copper chloride hydroxide was positively correlated with the formation of chlorinated aromatics in real fly ash and is, consequently, considered to be one of the key species involved in the formation of chlorinated aromatics.  相似文献   
24.
Nobuo Shuto 《Disasters》1983,7(4):255-258
The Japan Sea coast of Hokkaido and northern parts of the mainland were attacked by tsunamis (seismic sea-waves) and one hundred lives were lost, following the earthquake of May 1983. No tsunamis had previously been captured on so many photographs and video-cameras as this one. This note briefly describes the main features of this event.  相似文献   
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Over two decades of vulnerability assessments have shown the Pacific Islands region to be one of the regions most at risk to the adverse consequences of climate change. Pacific Island countries have shown strong leadership in characterising the challenges of climate change, both nationally and for the region as a whole, and in identifying the most appropriate responses. This paper reviews the various Vulnerability, Risk and Adaptation (VRiA) Assessment Methods and Tools that have been used across the Pacific Islands region, with an emphasis on the past two decades. The aim is to identify the approaches that are best suited to the region, and to develop a common understanding and principles that may be relevant and useful to harmonising the assessment of vulnerability and risk, and of adaptation options across the region. Even though assessments undertaken in the Pacific Islands region tend to share the common objective of reducing vulnerabilities and risks, practitioners in the Pacific are using numerous approaches, methods and tools to assess vulnerabilities and identify possible adaptation interventions. No one approach will address all needs and accommodate all capacities. Rather, several successful approaches, methods and tools are identified. The paper also identifies and assesses the approaches, methods and tools that have merit for further use, without or with further improvements. Lessons learned as well as success stories and success factors are documented. These findings are reflected in principles designed to assist harmonisation of approaches to VRiA assessment. These principles, in turn, influence the development of a proposed higher-level framework and approach for VRiA assessments. It accommodates the various approaches, methods and tools commonly used with success in the Pacific.  相似文献   
26.
Sewage sludge contains trace amounts of mercury, and sewage sludge incineration is a major source of mercury emissions. However, relatively few studies have reported on mercury emissions from sewage sludge incineration. Consequently, data on emissions from sewage sludge incinerators must be updated to estimate current emissions of mercury. In this study, we examined mercury emissions and speciation using continuous mercury analyzers in two incinerators. The mercury concentrations in stack gas from facilities A and B were 36.6 and 21.1???g/Nm3, respectively. As a result, the emission rate was calculated to be 0.282?C0.750?g/ton-dry sludge. Considering the total amount of sewage sludge incinerated in Japan, the mercury emissions from sewage sludge incinerators were estimated to be 0.49?C1.31?tons/year.  相似文献   
27.
Delignification from the cell walls with a combination of ozone oxidation and dioxane–water extraction using thin sections of a softwood, Japanese cypress (Chamaecyparis obtusa Endl.), was studied to determine its suitability for the production of recyclable cellulose-based materials from wood waste. The visible-light absorption spectra of treated wood sections revealed that delignification from the cell walls with ozone increased with increasing ozonization time. Ozone delignification proceeded from the lumen side toward the middle lamella within the secondary wall of a cell, and it proceeded faster in early wood than in late wood within an annual ring. Mild ozonization for 10–30 min was sufficient for the removal of lignin from the cell walls when sections were extracted with dioxane after ozonization. The results obtained here demonstrate that microspectrometry coupled with the Wiesner reaction is useful for the quantitative analysis of lignin in cell walls.  相似文献   
28.
煤粉炉内喷射吸收剂脱硫技术研究   总被引:1,自引:0,他引:1  
在一小型热态煤粉炉煤燃烧试验装置上,进行了炉内直接喷射吸收剂脱硫和二段燃烧降低NOx研究。试验显示脱硫效率与脱硫剂种类、喷入量和喷入位置有关,二段燃烧可降低NOx排放。以石灰石、白云石和消石灰比较,消石灰脱硫效果最佳;以CaCO3为脱硫剂,当Ca/S为4时,脱硫效率为80%;当喷入温度为1050℃,脱硫效果最好。合理的二段燃烧有利于降低NOx排放,但对SO2排放有一定的影响。   相似文献   
29.
The fate of the giant jellyfish Nemopilema nomurai after death was examined in the southwest Sea of Japan. The density of dead jellyfish was greater than that of live animals. The dead animals are heavier than the Japan Sea Proper Water which occurs deeper than 200 m, suggesting that dead jellyfish sink to the sea floor. The sea floor survey, conducted with a towed video tape recorder (VTR) monitoring system between mid September and mid October, observed a total of 138 jellyfish during 28 of 29 operations. The density of carrion ranged between 0.2 and 5.1 individuals/1,000 m2 (mean ± SE = 1.1 ± 0.2). Ophiuroids occurred abundantly at 23 jellyfish carcasses and a sea anemone was observed attached to five carcasses. The VTR surveys confirmed that carrion sinks to the sea floor not only during the winter, the normal end of life for medusae, but also during the fall. A trap survey baited with medusae was also employed, and four different species were sampled with the traps: the snow crab (Chionoecetes opilio), a shrimp (Pandalopsis japonica), the ivory shell (Buccinum striatissimum) and an ophiuroid (Ophiura sarsii). Much of the trap bait remained (49–68% weight-mean = 60.3%) during the 23 h soak-time, and the reduction in weight was greater than that observed by bacterial decomposition, suggesting benthic animals consume dead organisms. The present study indicates that dead N. nomurai sink to the sea floor continuously and were subsequently consumed by benthic scavengers.  相似文献   
30.
The purpose of this study was to examine the pattern of urinary protein excretion induced by 3 consecutive days of wildland firefighting. Eighteen male active-duty military personnel served as the participants. All testing on the 3 consecutive days was conducted at a Northwestern USA fire camp. All participants consumed military-based foods containing 2620–2864?kcal/day. The work activity was evaluated with an accelerometer in association with body weight and hydration markers over the experimental period. Urinary samples were collected pre and post workshift on days 1 and 3 to assess glomerular and tubular protein excretion (total protein, albumin, β2-microglobulin, N-acetyl-β-d-glucosaminidase and creatinine). The urinary levels of glomerular and tubular protein were not significantly different. The main findings of the present study indicate that similar alterations of urinary protein composition can be observed over consecutive days of wildland firefighting, which appears to be dependent on intensity rather than total work output.  相似文献   
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