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排序方式: 共有10000条查询结果,搜索用时 370 毫秒
991.
Anastassios Pouris 《Scientometrics》2007,70(3):541-553
This article reports the findings of a scientometric analysis of nanoscale research in South Africa during the period 2000–2005.
The ISI databases were identified as the most appropriate information platform for the objectives of the investigation and
have been interrogated for the identification of South African authors publishing in the field.
The article identifies trends over time, major institutional contributors, journals in which South African authors publish
their research, international collaborators and performance in comparison to four comparator countries (India, Brazil, South
Korea and Australia). The major findings of the investigation are as follows: nanoscale research in South Africa is driven
by individual researchers interests up to date and it is in its early stages of development; the country’s nanoscale research
is below what would one expect in light of its overall publication output; the country’s nano-research is distributed to a
number of Universities with subcritical concentration of researchers. 相似文献
992.
This paper describe an approach for improving the data quality of corporate sources when databases are used for bibliometric
purposes. Research management relies on bibliographic databases and citation index systems as analytical tools, yet the raw
resources for bibliometric studies are plagued by a lack of consistency in fied formatting for institution data. The present
contribution puts forth a Natural Language Processing (NLP)-oriented method for the identification of the structures guiding
corporate data and their mapping into a standardized format. The proposed unification process is based on the definition of
address patterns and the ensuing application of Enhanced Finite-State Transducers (E-FST). Our procedure was tested on address
formats downloaded from the INSPEC, MEDLINE and CAB Abstracts. The results demonstrate the helpfulness of the method as long
as close control of errors is exercised as far as the formats to be unified. The computational efficacy of the model is noteworthy,
due to the fact that it is firmly guided by the definition of data in the application domain. 相似文献
993.
Bibliometric analysis of tsunami research 总被引:3,自引:0,他引:3
The use of the bibilometric analytical technique for examining tsunami research does not exist in the literature. The objective
of the study was to perform a bibliometric analysis of all tsunami-related publications in the Science Citation Index (SCI).
Analyzed parameters included document type, language of publication, publication output, authorship, publication patterns,
distribution of subject category, distribution of author keywords, country of publication, most-frequently cited article,
and document distribution after the Indonesia tsunami. The US and Japan produced 53% of the total output where the seven major
industrial countries accounted for the majority of the total production. English was the dominant language, comprising 95%
of articles. A simulation model was applied to describe the relationship between the number of authors and the number of articles,
the number of journals and the number of articles, and the percentage of total articles and the number of times a certain
keyword was used. Moreover the tsunami publication patterns in the first 8 months after the Indonesia tsunami occurred on
26 December 2004 indicated a high percentage of non-article publications and more documents being published in journals with
higher impact factors. 相似文献
994.
995.
介绍了摩擦改进剂的类型及作用机理,比较了不同类型的摩擦改进剂。阐述了应用摩擦改进剂减少边界润滑和混合润滑状态下的摩擦损失,从而提高燃料经济性。 相似文献
996.
Remigiusz Sapa 《Scientometrics》2007,71(3):473-493
This article reports findings from the study of the international contribution to the system of library and information science
communication in Poland in the years 2003–2005. The sample consists of articles published both in selected journals and collective
works. Two important dimensions determining the internationalization of local scholarly communication are considered: direct
contribution (foreign authors’ articles and papers and their translations published in Poland) and indirect contribution (citedness
of foreign authors’ documents in articles and papers published in Poland). Bibliographic data about the geographical distribution
and affiliation of foreign authors are gathered and analyzed. Furthermore, the findings of citation analysis are presented
to determine the percentage share of citations received by foreign documents as well as to find out what is the structure
of such citations regarding the language and form, which thematic areas are most replete with such citations and which foreign
journals are most cited in Poland. 相似文献
997.
Claude Robert Concepción S. Wilson Jean-François Gaudy Charles-Daniel Arreto 《Scientometrics》2007,73(2):231-256
During the 1974–2004 period, the sleep literature had quadrupled (2384 publications in 1974, and 9721 in 2004) while overall
scientific productivity had only doubled. The set of the seven most productive countries (USA, Japan, United Kingdom, Germany,
France, Canada and Italy) in sleep research, and the geographical region distribution remained stable over the three decades.
On the other hand several indicators appeared in the sleep research literature during the 1990s: the increasing productivity
of sleep researchers; the growing number of countries publishing on sleep; the continuous creation of sleep-focused journals;
the scattering of sleep publication among increasingly more scientific journals; the turnover among the leading journals;
and the emergence of new entities such as China, Turkey, and the European Union. 相似文献
998.
Joachim Schummer 《Scientometrics》2007,70(3):669-692
Based on bibliometric methods, this paper describes the global institutionalization of nanotechnology research from the mid-1980s
to 2006. Owing to an extremely strong dynamics, the institutionalization of nanotechnology is likely to surpass those of major
disciplines in only a few years. A breakdown of the relative institutionalizations strengths by the main geographical regions,
countries, research sectors, disciplines, and institutional types provides a very diverse picture over the time period because
of different national science policies. The results allow a critical assessment of the different science policies based on
the relative institutionalizations strengths as well as the conclusion that the institutionalization process has run out of
control of individual governments who once induced the development. 相似文献
999.
Wei-Jun Liu Wei-Dong He Xue-Wu Ge Hua-Rong Liu Mo-Zheng Wang Zheng-Qi Chang 《Materials Letters》2007,61(13):2818-2821
Interfacial-initiated polymerization of styrene (St) was carried out in inversed emulsion with cumene hydroperoxide (CHPO) and ferrous sulfate (FeSO4)/disodium ethylenediaminetetraacetate (NaEDTA)/sodium formaldehyde sulfoxylate (SFS) as the redox initiation system. The water-soluble Fe2+-NaEDTA-SFS acted as the reducing component and the oil-soluble CHPO as the oxidant component of the redox initiation system. Therefore, the primary radicals were produced mainly at the oil/water interface to initiate the polymerization of St. Thus, sub-micrometer hollow polystyrene (PSt) spheres were obtained by one-stage polymerization, which was supported by the techniques of transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). 相似文献
1000.
The frequencies of multinational papers in various sciences 总被引:2,自引:1,他引:1
Helmut A. Abt 《Scientometrics》2007,72(1):105-115
Multinational papers are defined here as ones written by authors who reside in different countries during the course of research.
For each of 16 fields of science, I scanned the first 200 papers in 2005 in four major journals publishing original research
papers. Those journals produced 40% of all the citations among those journals with Impact Factors greater than 1.0. The frequencies
of multinational papers ranged from 13% in surgery to 55% in astronomy. Although one can list a dozen factors which might
contribute toward multinational papers, I lack the data to test most of those. There are only minor correlations with team
sizes and Impact Factors, inadequate to explain the range. There is a larger, but not convincing, dependence upon the fractions
of single-author papers and its cause, if real, is unclear. However, the most prominent factor seems to be the nature of the
objects studied; if they are usually local (e.g. in one hospital or in one laboratory), the papers tend to be domestic but
if most of the objects are available simultaneously to scientists in many countries (e.g. the sky in astronomy or the oceans
and the Earth’s atmosphere in geosciences or widespread diseases in the area of infectious diseases or plants and animals
widely distributed in biology), the papers are often international. Auxiliary results for 2005 are an average of 5.5 ± 0.3
authors per paper and 6.6 ± 1.0% one-author papers. 相似文献