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The application of fluorescence spectroscopy to organic matter characterisation in drinking water treatment 总被引:7,自引:0,他引:7
John Bridgeman Magdalena Bieroza Andy Baker 《Reviews in Environmental Science and Biotechnology》2011,10(3):277-290
Key to effective disinfection byproduct (DBP) management is source water control and management, and more specifically, organic
matter (OM) control and management. However, the content and character of OM in source waters is spatially and temporally
variable, and the prediction of its composition is challenging. Water treatment companies require adequate analytical techniques
for OM characterisation to maintain the operation of the water supply and treatment systems adjusted to constantly changing
environmental conditions. There is a requirement, therefore, for an improved understanding of OM composition and character
in source water, how that composition and character varies with flow conditions, and how this impacts on drinking water treatment.
This paper demonstrates that fluorescence spectroscopy offers a potential alternative to other analytical methods of OM characterisation.
The advantages of fluorescence include rapid, sensitive and selective characterisation of OM, no sample pre-treatment, small
sample volume, and the potential for on-line monitoring incorporation. Fluorescence can provide useful information on OM reactivity
and treatability together with an indication of the OM sources (allochthonous or autochthonous). The paper discusses a body
of literature which has identified relationships between fluorescence spectra and OM physico-chemical properties (i.e. degree
of hydrophobicity, microbial content), has applied fluorescence spectroscopy to characterise the changes in OM upon disinfection,
and has related the fluorescence properties to DBP formation. Further work is required in the robust management of data arising
from fluorescence spectroscopy analysis and, in particular, Excitation Emission Matrices. Consideration must be given as to
how the data might best be employed to greatest effect on a routine basis at WTW. 相似文献
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The number of AIDS cases in individuals 50 years of age or older in the United States is reported to exceed 9000. Contaminated blood and blood transfusions are major contributors to HIV-1 infection in this age group. Sexual transmission and infection through intravenous drug abuse are also potential avenues of HIV-1 transmission in the older population. AIDS presents with a variety of clinical manifestations, including dementia, frequently seen in non-HIV-1-infected older people. Neurological deficiencies associated with AIDS are very common and may lead to misdiagnosis in the elderly. The observed incubation period of HIV-1 infection is longer than previously estimated, increasing the risk of older individuals exposed to HIV-1 in the past to develop AIDS. Oral manifestations may present as one of the early clinical signs of AIDS. Little is known concerning AIDS in the geriatric population. It demands consideration by dental professionals treating older individuals belonging to one of the exposure categories of the disease. 相似文献
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Nicola Bryson-Morrison Andy Beer Aly Gaspard Soumah Tetsuro Matsuzawa Tatyana Humle 《American journal of primatology》2020,82(3):e23102
Agricultural expansion encroaches on tropical forests and primates in such landscapes frequently incorporate crops into their diet. Understanding the nutritional drivers behind crop-foraging can help inform conservation efforts to improve human-primate coexistence. This study builds on existing knowledge of primate diets in anthropogenic landscapes by estimating the macronutrient content of 24 wild and 11 cultivated foods (90.5% of food intake) consumed by chimpanzees (Pan troglodytes verus) at Bossou, Guinea, West Africa. We also compared the macronutrient composition of Bossou crops to published macronutrient measures of crops from Bulindi, Uganda, East Africa. The composition of wild fruits, leaves, and pith were consistent with previous reports for primate diets. Cultivated fruits were higher in carbohydrates and lower in insoluble fiber than wild fruits, while wild fruits were higher in protein. Macronutrient content of cultivated pith fell within the ranges of consumed wild pith. Oil palm food parts were relatively rich in carbohydrates, protein, lipids, and/or fermentable fiber, adding support for the nutritional importance of the oil palm for West African chimpanzees. We found no differences in the composition of cultivated fruits between Bossou and Bulindi, suggesting that macronutrient content alone does not explain differences in crop selection. Our results build on the current understanding of chimpanzee feeding ecology within forest-agricultural mosaics and provide additional support for the assumption that crops offer primates energetic benefits over wild foods. 相似文献