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Difficulties in the localization of bodies of homicidal or drowning victims in natural water result in their submergence for weeks if not months. Water insects and microbes drastically change the body's appearance, which significantly changes the determination of a victim's identity. DNA analysis is commonly used for identifying the decedent; however, this PCR-based approach is time-consuming and destructive of the evidence. Considering that nearly half of the people in the world dye their hair with a variety of permanent and semi-permanent dyes, one can expect that confirmatory identification of dyes on the body's hair can be used to shed light on the victim's identity. A growing body of evidence suggests that surface-enhanced Raman spectroscopy (SERS) can be used to detect and identify hair dyes. In this study, we investigated the extent to which SERS could be used to detect black and blue, permanent and semi-permanent dyes on hair submerged in hypolimnion water for up to twelve weeks. We found that SERS enabled 100% accurate identification of analyzed dyes on hair submerged in hypolimnion water for up to 8 weeks, whereas, on average, 87% accurate identification of the hair dyes could be achieved on hair exposed for 10 weeks and 50% for hair exposed 12 weeks in hypolimnion water. We also found that the aqueous environment caused progressive fading of some dyes, whereas other dyes showed substantial spectral transformations after prolonged submergence. Finally, we found that changes in the intensity of vibrational bands of dyes could be used to predict the duration of submergence of colored hair in hypolimnion water.  相似文献   
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Studies assessing the use of ground-penetrating radar (GPR) for locating unmarked human graves commonly use pigs as proxies, with recent concerns about the adequacy of pigs as substitutes for humans. Also, there is little agreement on how to identify and describe GPR signals associated with graves. Hence, this project's aim is to compare GPR signals acquired over simulated clandestine graves with pig and human remains. We established human, pig, and control graves at the REST[ES] human decomposition facility in May 2022 and monitored the graves over 17 months using a 250 MHz antenna GPR system. Our results showed the presence of perturbed and V-shaped reflectors, diffraction hyperbolas, and reflectors with amplitude loss at depth between 0.6 and 0.75 m in the radargram for graves with human and pig remains. We corroborate recent studies which concluded that the use of proxies is a viable alternative to human cadavers. The observed radar signatures were classified into five key patterns, which are characteristic of similar data collected with 250 MHz above graves reported in the literature. These classes are: V-shaped dipping reflections from grave walls (class A), small hyperbolic reflections superimposed onto a near-linear reflector (class B), hyperbolic reflections from remains within the grave (class C), new high-amplitude reflection patterns (class D) and significant loss or interruption of reflections (class E). Our proposed classification can help streamline future investigations where the goal is to interpret burials within large GPR datasets and provide language to communicate these results to the broader scientific community.  相似文献   
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The current study responds to the lack of understanding about the temperatures experienced by individual blow fly larvae within “maggot masses.” The temperature selection of both aggregating (in a mass) and nonaggregating larvae was compared and their pattern of movement assessed. Infrared imaging determined the temperatures within a mass and in the vicinity of the constituent individual larvae, whose movements were tracked by dyeing their tissues red. Individual Chrysomya rufifacies larvae selected temperatures above 27°C, significantly higher than the temperature selected by Calliphora vicina larvae (24.5°C). However, this same difference was not seen within a mass, with both species selecting temperatures around 28°C. Larval movement in a mass was nonrandom, indicating that larvae actively select their position in a mass. Furthermore, larvae have a strong tendency to select the hottest part of a mass; therefore, maximum mass temperatures might provide a reliable proxy for the actual temperatures experienced by larvae.  相似文献   
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Book review     
Aspects of Development and Underdevelopment. By Joan Robinson. Cambridge‐Cambridge University Press (Modern Cambridge Economics), 1979. Pp. x + 146. Hardback £7.95, paperback £2.50.

From Modernization to Modes of Production: a critique of the sociologies of development and underdevelopment. By John G. Taylor. London: Macmillan, 1979. Pp. xii + 335. Hardback £12, paperback £4.95.

Theories of Underdevelopment. By Ian Roxborough. London: Macmillan, 1979. Pp. xii + 175. Hardback £10, paperback £3.95.

Development Administration: Concepts, Goals, Methods. By George F. Gant. Madison: University of Wisconsin Press, 1979. Pp. xii + 343. $21.50.

Developing Country Debt. Edited by Lawrence G. Franco and Marilyn J. Seiber. New York: Pergamon Press, 1979. Pp. xi + 309. £20.

The Lending Policy of the World Bank in the 1970s: Analysis and Evaluation. By Bettina S. Hürni. Boulder, Colorado: Westview Press, 1980. Pp. xvi + 173. $20.

The World Bank and the Poor. By Aart van de Laar. Boston, The Hague: Martinus Nijhoff, 1980. Pp. xii + 260. $15.

The New Authoritarianism in Latin America. Edited by David Collier. Princeton: Princeton University Press, 1979. Pp. v + 456. Hardback £15.10, paperback £3.65.

The Political Economy of Peru 1956–78: Economic development and the restructuring of capital. By E. V. K. FitzGerald. Cambridge: Cambridge University Press, 1979. Pp. xi + 360. £17.50.

Scarcity and Survival in Central America. By William H. Durham. Stanford: Stanford University Press, 1979. Pp. xvii + 209. £14.50.

Peasants and Poverty: A Study of Haiti. By Mats Lundahl. London: Croom Helm, 1979. Pp. 699. £19.95.

The Rational Peasant: The Political Economy of Rural Society in Vietnam. By Samuel L. Popkin. Berkeley: University of California Press, 1979. Pp. xxi + 306. £9.

The Economy of Kenya: the Kenyatta Era. By Arthur Hazlewood. Oxford: Oxford University Press, 1979. Pp. x + 231. Hardback £9, paperback £4.95.

Chinese Education in Transition: Prelude to the Cultural Revolution. By Julia Kwong. Montreal: McGill‐Queen's University Press, 1979. Pp. xi + 207 $13.95.

Hydropolitics of the Nile Valley. By John Waterbury. Syracuse, N.Y.: Syracuse University Press, 1979. Pp. xii + 301. $20.

The Volta River Project: A Case Study in Politics and Technology. By David Hart. Edinburgh: Edinburgh University Press, 1980. Pp. 142. £7.50.

Economic Development, Cities and Planning: The Case of Bombay. By Nigel Harris. Bombay: Oxford University Press, 1979. Pp. vi + 93. £5.15.

Sociological Analysis of the Working of Small Farmers Development Agency. By Mumtaz Ali Khan. Simla: Indian Institute of Advanced Study, 1978. Pp. x + 175. Rs. 32.

Planning for Basic Needs in Kenya: Performance, Policies and Prospects. By Dharam Ghai, Martin Godfrey and Franklyn Lisk. Geneva: International Labour Office, 1979. Pp. x + 167. £5.

Women in Rural Development: the People's Republic of China. By Elisabeth Croll. Geneva: International Labour Office, 1979. Pp. 61. Paperback, £3.75.  相似文献   
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Ownership versus competition: Efficiency in public enterprise   总被引:2,自引:0,他引:2  
Certainly the introduction of product market competition into potentially competitive or, at least contestable, markets can improve performance. To take just one example, Morrison and Whinston (1986, 1986) estimate that even in the imperfectly contestable U.S. airline industry, the annual U.S. welfare gains from deregulation have been around $6 billion.But this paper argues, and further buttresses empirically, that ownership also matters and matters a lot. This does not necessarily imply that private ownership is always preferable to public ownership. PCs also engage in rent-seeking where possible, but they will try to maximize realizable rents by (relatively) keeping down production costs. Of course, where there are massive economies of scale and scope, high entry barriers, or externalities, public ownership may be preferred. (see Vickers and Yarrow, 1988).  相似文献   
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This article characterizes the perceptions of government bureaucrats about cost-benefit analysis (CBA). The observations arise after working with government officials on various projects and leading many executive seminars for government employees over the last decade on the principles and practice of CBA. Government employees tend to adopt one of three conceptual lenses: Guardians, Spenders, and Analysts. These perspectives differ sharply from one another, resulting in completely different meanings to the words benefits and costs. The orientation of Guardians is to “revenue-expenditure” analysis, while Spenders are oriented to “constituency-support” analysis. Analysts are oriented to standard CBA. The differences in perspectives are illustrated using an ex ante CBA of a proposed toll highway project.  相似文献   
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