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81.
Ab initio calculations have been performed to determine the energetics of oxygen atoms adsorbed onto graphene planes and the possible reaction path extracting carbon atoms in the form of carbon monoxide. From the energetics it is confirmed that this reaction path will not significantly contribute to the gasification of well ordered carbonaceous chars. Modelling results which explore this limit are presented. 相似文献
82.
We discuss the design and implementation of network and transport layer protocols for mobile networking. The network architecture used is unique in that it separates the mobile network(s) from fixed networks and provides connectivity between the two via special gateways. These gateways split all transport connections and provide QoS guarantees to mobile users for all their open connections. We provide summaries of our protocols and discuss possible improvements. 相似文献
83.
Recently scientists have investigated what statistical distributions can be used to describe the distribution of the number
of authors per article.Ajiferuke has undertaken the most comprehensive study of this problem. He has found that by and large the Inverse Gaussian-Poisson
distribution could describe most properly the observed authorship distributions. However, it is well known that this distribution
is rather intricate, soRousseau tried to fit some simple one-parameter distributions to the number of authors of LIS articles. He has found that the geometric
and the truncated Poisson distribution adequately describe these authorship data sets. The main purpose of the present paper
is to continue these investigations and to analyse and test the viability of simple statistical distributions. As to (sub)fields
where the single author dominates the results ofRousseau were corroborated: the truncated Poisson and the geometric distribution give often adequate fits to describe the number of
authors. The Lotka distribution should be rejected. The truncated binomial distribution and the truncated negative binomial
were investigated as well. However, it is not clear whether they are acceptable candidates. 相似文献
84.
This paper presents two simple algorithms for computing the point-to-point congestion probability in a switched communication network. Methods are straightforward and can easily be computerized. Examples illustrate the methods. 相似文献
85.
Bajpai-Dikshit J Suresh AK Venkatesh KV 《Journal of Bioscience and Bioengineering》2003,96(5):481-486
A comprehensive model was developed to simulate Lactobacillus rhamnosus growth on a medium containing multiple limiting carbon sources. The strategy of optimizing specific growth rate to predict growth on multiple substrates was demonstrated. The model predictions were based on parameters obtained from L. rhamnosus growth on individual substrates. The model was able to simulate the growth, substrate consumption, product formation and specific growth rate profiles of L. rhamnosus accurately. The model prediction that co-metabolism of glucose and pyruvate enhances growth rate of and flavor production by the bacterium was experimentally verified. 相似文献
86.
87.
This paper is a modified version of a lecture which describes the synthesis, structure and reactivity of some neutral molecules of stellar significance. The neutrals are formed in the collision cell of a mass spectrometer following vertical Franck-Condon one electron oxidation of anions of known bond connectivity. Neutrals are characterised by conversion to positive ions and by extensive theoretical studies at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31G(d) level of theory. Four systems are considered in detail, viz (i) the formation of linear C(4) and its conversion to the rhombus C(4), (ii) linear C(5) and the atom scrambling of this system when energised, (iii) the stable cumulene oxide CCCCCO, and (iv) the elusive species O(2)C-CO. This paper is not intended to be a review of interstellar chemistry: examples are selected from our own work in this area. 相似文献
88.
A. Srirama Rao B. R. Phanikumar R. Dayakar Babu K. Suresh 《Canadian Metallurgical Quarterly》2007,133(5):531-538
Granular pile anchors (GPA) are one of the recent innovative foundation techniques devised for mitigating the problems posed by swelling clay beds. In a granular pile anchor, the footing is anchored to an anchor plate at the bottom of the granular pile. This makes the granular pile tension resistant and enables it to absorb the tensile force caused on the foundation by the swelling clay. An understanding of the amount of uplift resistance offered by the GPA is important in the design of granular pile-anchor foundations in field situations causing tensile forces on foundations, such as in expansive clay beds. This paper presents the results of a field-scale test program conducted to study the pullout response of GPAs embedded in expansive clay beds. Pullout load tests were conducted on GPAs of varying lengths and diameters. It was found from the field pullout load tests that granular pile anchors of larger surface area resulted in higher pullout capacity. Of the various single granular pile anchors with l/d values between 2.5 and 10, the GPA of length 1000?mm and diameter 200?mm (l/d = 5) showed the best pullout load response when tested alone, resulting in a failure uplift capacity of 14.71?kN. Increase in diameter and length of granular pile anchor increased the uplift capacity. When the length of the GPA was increased from 500 to 750 and 1000?mm, the percentage increase in the uplift load required for an upward movement of 25?mm was 33.3 and 55.5% respectively. The pullout load of the GPA when tested under group was 18?kN as against a 12?kN for the GPA when tested single. 相似文献
89.
Biomarkers are measurable indicators of a biological state. As our understanding of diseases meliorates, it is generally accepted that early diagnosis renders the best chance to cure a disease. In the context of proteomics, the discovery phase of identifying bonafide biomarkers and the ensuing validation phase involving large cohort of patient samples are impeded by the complexity of bodily fluid samples. High abundant proteins found in blood plasma make it difficult for the detection of low abundant proteins that may be potential biomarkers. Extracellular vesicles (EVs) have reignited interest in the field of biomarker discovery. EVs contain a tissue-type signature wherein a rich cargo of proteins and RNA are selectively packaged. In addition, as EVs are membranous structures, the luminal contents are protected from degradation by extracellular proteases and are highly stable in storage conditions. Interestingly, an appealing feature of EV-based biomarker analysis is the significant reduction in the sample complexity compared to whole bodily fluids. With these prescribed attributes, which are the rate-limiting factors of traditional biomarker analysis, there is immense potential for the use of EVs for biomarker detection in clinical settings. This review will discuss the current issues with biomarker analysis and the potential use of EVs as reservoirs of disease biomarkers. 相似文献
90.
Aravind Suresh Joysurya Basu C. Barry Carter Nigel Sammes B. A. Wilhite 《Journal of Materials Science》2010,45(12):3215-3227
Cobalt-doped barium cerate-zirconate was synthesized using an oxalate co-precipitation route. The material was characterized
using X-ray diffraction, transmission and scanning transmission electron microscopy coupled with X-ray energy dispersive spectroscopy.
Results indicated that homogeneous cubic phase material was obtained at very high heat-treatment temperatures. Catalytic activity
of the material toward CH3OH partial-oxidation was tested at different temperatures and O2:CH3OH ratios. High hydrogen yields were obtained indicating that the material was a suitable catalyst for hydrogen generation.
Impedance spectroscopy tests were conducted at different conditions to understand conduction processes occurring in the material.
Results suggested mixed protonic–electronic conductivity in the presence of hydrogen. Thus, material is a potential candidate
for the bi-functional role of electro-ceramic catalyst for simultaneous hydrogen generation and purification. 相似文献