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排序方式: 共有143条查询结果,搜索用时 15 毫秒
71.
The 26 December 2004 tsunamis around the Indian Ocean exposed the vulnerability of many coastal communities, including those serving tourists. To draw conclusions regarding disaster risk reduction for tourism in coastal areas, this study surveyed international tourists who survived the tsunami regarding their perceptions and experiences of the disaster. Semi-structured interviews were completed between January and June 2005 of 55 primary interviewees who were international tourists in locations affected by the tsunami. The qualitative data from the interviews yielded commonalities across four main themes with relevance to disaster risk reduction: information and awareness, warning systems, personal preparation, and livelihoods. Three areas are suggested as topics to highlight for further investigation: the connections between sustainable tourism and disaster vulnerability, the role of tourists in disasters, and disaster risk reduction education.  相似文献   
72.
K. Yamaguchi 《Marine Biology》1998,132(4):651-661
The mobility of Anomia chinensis Philippi was studied in relation to its byssal development stage. This species shows high mobility even after it begins cementation in its post-larval stage. Juveniles develop a calcified byssus in the post-larval stage and cement to substrata. However, juveniles up to about 10 mm in shell length can relocate by repeating a sequence of formation of the calcified byssus, abandonment of it, locomotion by crawling, reattachment, and recementation. Juvenile anomiids up to 25 mm in shell length also can move, without breaking their byssal attachments, by shifting the center of byssal calcification dorsally. Even an adult can change its orientation by forming a twisted byssus. These possible methods of movement are closely related to five stages of byssal development. Anomiids can use this mobility to seek a preferable position for attachment after initial cementation, or to adjust their orientation, and thus promote higher survivorship. Received: 18 August 1997 / Accepted: 19 July 1998  相似文献   
73.
Disaster recovery is a dynamic process of creating, maintaining, and changing the meaningful context of survivors. It is completed when they redevelop their self‐reliance and resume managing their social relations with a sense of community. This study employed action research to examine how researchers and survivors collaborated to change disaster recovery through the generative power of metaphor in a small village in Japan that experienced the Niigata–Chuetsu earthquake on 23 October 2004. It outlines long‐term collaborative practices as survivors undertook new activities owing to the power of the metaphor of ‘school’. Once ‘school’ was adopted as the metaphor for where survivors learnt new skills and passed on traditional knowledge, they created new metaphors and performed new activities independently, which is critical for recovery as it demonstrates self‐reliance. The paper assesses the reasons why generative metaphors worked effectively in this case and highlights some academic and practical implications for disaster recovery.  相似文献   
74.
The salting-out effect by seawater constituents on the water solubilities of 11 aromatic compounds, anthracene, pyrene, phenanthrene, biphenyl, naphthalene, p-nitrotoluene, p-toluidine, o-nitrophenol, m-nitrophenol, p-nitrophenol and phenol was investigated. A best fit equation (r = 0.965) for the salting-out parameters, K, and distilled water solubilities, So, at 20°C was found to be K = ?0.0298 log So + 0.114. Seawater solubilities, S, predicted for solutions of ionic strength, I, using the equation log S = (0.0298 I + 1) log So ? 0.114 I were in agreement with observed values within 13 % (average 4.8 %) and there were no significant differences between values from the Pacific Ocean seawater and those from 35 o/oo NaCl solutions. It was concluded that dissolved organic matter in seawater had an insignificant effect for the test chemicals.  相似文献   
75.
Experimental cultivations of post-metamorphosis juveniles were repeated in different seasons for Ciona intestinalis (L.) and Styela plicata (Lesueur) (simple ascidians) as well as for Leptolinum mitsukurii (Oka) and Botrylloides violaceus Oka (compound ascidians) at Aburatsubo-Moroiso Inlet near Misaki Biological Station (Japan). Growth in body length of simple ascidians was exponential during juvenile development up to near sexual maturity. C. intestinalis grew to sexual maturity in 1 month in summer and in 2 months in winter; S. plicata, in 2 months in summer and in nearly 5 months in winter. The doubling time decreased approximately twofold in the two simple ascidians with a 10C° increase in environmental temperature. Growth of colonies in compound ascidians was exponential after maturation of the first functional zooids. Sexual reproduction of L. mitsukurii and B. violaceus was continuous throughout the year, forming many generations in a year. Doubling time of colony growth in the two compound ascidians decreased approximately threefold with a 10C° increase in temperature.  相似文献   
76.
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78.
To obtain basic information for evaluating critical levels of O3 under different nitrogen loads for protecting Japanese beech forests, two-year-old seedlings of Fagus crenata Blume were grown in potted andisol supplied with N as NH4NO3 solution at 0, 20 or 50 kg ha−1 year−1 and exposed to charcoal-filtered air or O3 at 1.0, 1.5 and 2.0 times the ambient concentration from 16 April to 22 September 2004. The O3 induced significant reductions in the whole-plant dry mass, net photosynthetic rate at 380 μmol mol−1 CO2 (A 380), carboxylation efficiency (CE) and concentrations of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and total soluble protein (TSP) in the leaves. The concentrations of Rubisco and TSP were negatively correlated with the concentration of leaf acidic amino acid, suggesting that O3 enhanced the degradation of protein such as Rubisco. The N supply to the soil did not significantly change the whole-plant dry mass and A 380, whereas it significantly increased the CE and concentrations of Rubisco and total amino acid. No significant interactive effects of O3 and N supply to the soil were detected on the growth, photosynthetic parameters and concentrations of protein and amino acid in the leaves. In conclusion, N supply to the soil at ≤50 kg ha−1 year−1 does not significantly change the sensitivity to O3 of growth and net photosynthesis of Fagus crenata seedlings.  相似文献   
79.
A method of estimating the length of the exponential growth phase is developed by solving a difference equation derived from the regression of growth increments on the initial sizes. This method facilitates quick assessments of the juvenile lifespan of animals, e.g. the coral-reef asteroid Culcita novaeguineae, which grow exponentially with very low growth rates. The juvenile life span of C. novaeguineae was estimated to be about 2 years from metamorphosis to transformation into the pin-cushion form.Supported by NSF Grant GA-39948. Contribution No. 87, University of Guam Marine Laboratory.  相似文献   
80.
Ishii N  Tagami K  Uchida S 《Chemosphere》2004,57(8):953-959
The behavior of an element in the environment depends on its physicochemical form. Basic data for the behavior of technetium in an agricultural environment were obtained by determining the physicochemical forms of Tc in 28 surface water samples from paddy and upland fields. Most of the (95m)Tc was present as TcO(4)(-) in the samples. The relative amount of this chemical form was 72% on average. A significant amount of insoluble Tc (particles more than 0.2 microm in size), however, was found in some samples. The maximum amount of the insoluble Tc was 91%. Other forms were found in insignificant amounts. The amount of insoluble Tc was relatively high in paddy soil samples. Paddy soils, gley soils and gray lowland soils were particularly effective in the insolubilization of Tc. Among the soil characteristics studied, cation exchange capacity, anion exchange capacity, and active aluminum showed significant correlations with the relative amount of insoluble Tc. When microorganisms were eliminated from the surface water samples before the addition of (95m)TcO(4)(-), little insoluble Tc was found, suggesting that microorganisms cause the physicochemical transformation. These results showed that the physicochemical form of Tc changes from TcO(4)(-) to insoluble forms in surface water covering paddy fields. The insoluble forms would restrict the mobility of Tc in paddy fields.  相似文献   
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