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131.
Pradeep K. Sahoo Sandeep Kumar Ramesh P. Singh 《International journal of remote sensing》2013,34(3):499-518
The Ganga and Yamuna rivers emerge from the Himalayas along two major faults known as the Ganga and Yamuna Tear Faults respectively. The two major strike-slip faults transverse to the Siwalik range are clearly seen in satellite imagery of the Dehradun area. Earthquake records, landslide and recent changes in geomorphological features indicate that the area between the Main Boundary Thrust and the Main Frontal Thrust is tectonically active. An effort has been made to study the tectonic evolution and neotectonism of the Ganga and Yamuna tear faults. Spectral and spatial enhancement techniques have been employed to the digital data of IRS-1B LISS-I to delineate the lineaments and major faults of the area. Based on Mohr's theory, failure criteria and statistical analysis of remotely sensed lineament data, horizontal compressive stress values (SHmax) have been estimated at various sites of the study area. These data are found to be consistent with the published SHmax orientation determined from earthquake focal mechanism solutions. Active faults and lineaments have been extracted from the remotely sensed lineament data. Past earthquake data and depth to basement contour data have been used in an integrated approach with available Geographic Information System (GIS) techniques to reconstruct a present-day regional geodynamic model. Attempts have been made to investigate the genesis of Ganga and Yamuna Tear Faults and possible causes of recent tectonic activities of the area with the help of the proposed geodynamic model. 相似文献
132.
Tropical cyclones form over the seas: a typical data‐sparse region for conventional observations. Therefore, satellites, especially with microwave sensors, are ideal for cyclone studies. The advanced microwave sounding unit (AMSU) , in addition to providing very valuable data over non‐precipitating cloudy regions, can provide very high horizontal resolution of the temperature and humidity soundings. Such high‐resolution microwave data can improve the poorly analysed cyclone. The objective of this study is to investigate the impact of ingesting and assimilating the AMSU data together with conventional upper air and surface meteorological observations over India on the prediction of a tropical cyclone which formed over the Arabian Sea during November 2003 using analysis nudging. The impact of assimilating the AMSU‐derived temperature and humidity vertical profiles in a mesoscale model has not been tested yet over the Indian region. Such studies are important as most weather systems over India form over the seas. The present study is unique in the sense that it addresses the impact of ingesting and assimilating microwave sounding data (together with conventional India Meteorological Department data) on the prediction of a tropical cyclone, which formed over the Arabian Sea during November 2003 using analysis nudging. Two sets of numerical experiments are designed in this study. While the first set utilizes the National Center for Environmental Prediction (NCEP) reanalysis (for the initial and lateral boundary conditions) only in the fifth‐generation mesoscale model simulation, the second set utilized the AMSU satellite and conventional meteorological upper air and surface data to provide an improved analysis through analysis nudging. The results of the two sets of model simulations are compared with one another as well as with the NCEP reanalysis and the observations. The results of the study indicated that the impact of ingesting and assimilating microwave sounding data and the conventional meteorological data through nudging resulted in an improvement in the simulation of wind asymmetries and the warm temperature anomalies. The with‐assimilation run simulated stronger wind speeds and stronger vertical velocity motion as compared with the without‐assimilation run. The time series of the minimum sea level pressure (SLP) and maximum wind speed for the simulations with the microwave sounding data and conventional meteorological data show better agreement with the observations than the simulations without the assimilation. The central minimum pressure of the simulations with the modified analysis are lower by 7 hPa as compared with the simulations without the assimilations. Even though there is not much of a difference in the maximum wind speed between the two simulations at the initial forecast time, the results indicate that the simulations with microwave sounding data and conventional meteorological data reveal a marked (9 m/s) increase in the maximum wind speed over the simulations without the assimilation. While the lowest central pressure estimated from the satellite image is 988 hPa, the simulations with microwave sounding data and conventional meteorological data show a value of 999.5 hPa for the lowest central minimum pressure. One reason for the inability of the simulation with improved analysis to achieve the observed lowest SLP is that the NCEP reanalysis had manifested an extremely weak system in the first place and, despite assimilation with microwave sounding data and conventional meteorological data, only a moderate improvement in the lowest SLP could be achieved. A proper appreciation of the impact of the microwave sounding data can be obtained by comparing with the lowest SLP obtained from the simulation without assimilation which showed a value of 1007 hPa. The initial mis‐representation in the location of the centre of the cyclone in the NCEP reanalysis with respect to the observed location has led to marked errors in the track prediction of both the model simulations. The assimilation of microwave satellite data is yet to be implemented in the current operational regional model over India and hence the results of this study may be relevant to the operational tropical cyclone forecasting community. 相似文献
133.
134.
DC Reynolds CE Leak KK Bajaj CE Stutz RL Jones KR Evans PW Yu WM Theis 《Canadian Metallurgical Quarterly》1989,40(9):6210-6217
135.
Sandeep Yalagala Rambabu T. Kunja Laxminarayana Borang Oimang Aravind G. Dode Aparna Nathanial V. 《Journal of Materials Science: Materials in Electronics》2022,33(2):635-651
Journal of Materials Science: Materials in Electronics - The nano-crystalline particles of erbium-substituted Ni–Zn ferrites with compositional formula Ni0.7Zn0.3ErxFe2?xO4... 相似文献
136.
KR Beutner SK Tyring KF Trofatter JM Douglas S Spruance ML Owens TL Fox AJ Hougham KA Schmitt 《Canadian Metallurgical Quarterly》1998,42(4):789-794
Genital human papillomavirus infection is one of the most common sexually transmitted diseases. Imiquimod is a new agent, an immune-response modifier, that has been demonstrated to have potent in vivo antiviral and antitumor effects in animal models. The present prospective, multicenter, double-blind, randomized, vehicle-controlled trial evaluated the efficacy and safety of daily patient-applied imiquimod for up to 16 weeks for the treatment of external genital warts. Wart recurrence was investigated during a 12-week treatment-free follow-up period. In the intent-to-treat analysis, baseline warts cleared from 49 of 94 (52%) patients treated with 5% imiquimod cream, 13 of 90 (14%) patients treated with 1% imiquimod cream, and 3 of 95 (4%) vehicle-treated patients; the differences between the groups treated with vehicle and imiquimod were significant (P < 0.0001). For subjects who completed the follow-up period, recurrence rates after a complete response were 19% (9 of 48 patients) in the 5% imiquimod cream group, 17% (2 of 12) in the 1% imiquimod cream group, and 0% (0 of 3) in the vehicle-treated group. There were no systemic reactions, although local skin reactions (generally of mild or moderate severity) were common, particularly in the 5% imiquimod cream group. Local reactions caused two patients to discontinue treatment. The most frequently reported local skin reactions were erythema, excoriation or flaking, and erosion. Patient-applied 5% imiquimod cream is effective for the treatment of external genital warts and has a favorable safety profile. 相似文献
137.
The authors report a series of studies designed to determine whether effects similar to those observed in the innate categorical perception of color and phonemes are induced during the learning of simple unidimensional categories and more complex multidimensional ones. In Experiment 1 no evidence was found for such effects when stimuli varied on 1 dimension. Experiments 2 and 3 demonstrated a within-category compression effect but no between category expansion effect for stimuli varying in 2 dimensions. Compression only was also shown in Experiment 4, which used pictures of actual objects. Multidimensional scaling analyses illustrate how within-category compression without expansion was sufficient to produce categorical clustering of items in the similarity space. These analyses also show that learning changed the dimensional structure of similarity space. Results are compared with those from other studies exploring similar phenomena and with neural network simulations. 相似文献
138.
HS Keirstead JK Dyer GN Sholomenko J McGraw KR Delaney JD Steeves 《Canadian Metallurgical Quarterly》1995,15(10):6963-6974
Transections of the chicken spinal cord after the developmental onset of myelination at embryonic day (E) 13 results in little or no functional regeneration. However, intraspinal injection of serum complement proteins with complement-binding GalC or 04 antibodies between E9-E12 results in a delay of the onset of myelination until E17. A subsequent transection of the spinal cord as late as E15 (i.e., during the normal restrictive period for repair) results in neuroanatomical regeneration and functional recovery. Utilizing a similar immunological protocol, we evoked a transient alteration of myelin structure in the posthatching (P) chicken spinal cord, characterized by widespread "unravelling" of myelin sheaths and a loss of MBP immunoreactivity (myelin disruption). Myelin repair began within 7 d of cessation of the myelin disruption protocol. Long term disruption of thoracic spinal cord myelin was initiated after a P2-P10 thoracic transection and maintained for > 14 d by intra-spinal infusion of serum complement proteins plus complement-binding GalC or 04 antibodies. Fourteen to 28 d later, retrograde tract tracing experiments, including double-labeling protocols, indicated that approximately 6-19% of the brainstem-spinal projections had regenerated across the transection site to lumbar levels. Even though voluntary locomotion was not observed after recovery, focal electrical stimulation of identified brainstem locomotor regions evoked peripheral nerve activity in paralyzed preparations, as well as leg muscle activity patterns typical of stepping in unparalyzed animals. This indicated that a transient alteration of myelin structure in the injured adult avian spinal cord facilitated brainstem-spinal axonal regrowth resulting in functional synaptogenesis with target neurons. 相似文献
139.
KR Solomon EA Kurt-Jones RA Saladino AM Stack IF Dunn M Ferretti D Golenbock GR Fleisher RW Finberg 《Canadian Metallurgical Quarterly》1998,102(11):2019-2027
Septic shock induced by lipopolysaccharide (LPS) triggering of cytokine production from monocytes/macrophages is a major cause of morbidity and mortality. The major monocyte/macrophage LPS receptor is the glycosylphosphatidylinositol (GPI)-anchored glycoprotein CD14. Here we demonstrate that CD14 coimmunoprecipitates with Gi/Go heterotrimeric G proteins. Furthermore, we demonstrate that heterotrimeric G proteins specifically regulate CD14-mediated, LPS-induced mitogen-activated protein kinase (MAPK) activation and cytokine production in normal human monocytes and cultured cells. We report here that a G protein binding peptide protects rats from LPS-induced mortality, suggesting a functional linkage between a GPI-anchored receptor and the intracellular signaling molecules with which it is physically associated. 相似文献
140.
There is a growing body of research on the successes and failures of information and communications technology (ICT) projects in the public sector. However, this literature has rarely addressed the question of why some projects persist and continue despite functioning poorly in several areas. In this paper, we suggest that the notions of institutional logics and status differences provide useful insights into the structure and trajectory of this type of continuity. We build our arguments through an in-depth qualitative case study of a public information and communications technology (PICT) project in India. From our findings, we develop a process model of PICT project continuity. We explain how the employment of bureaucratic posturing – a manifestation of bureaucratic logic – as a tactic by high status groups could lead to poor performance on several fronts. The paper elaborates on two levels of continuity: policy-level continuity, which in our case was enabled by the logics of decentralization and technocracy, and operational-level continuity, which was achieved when groups with contrasting status-related motivations supported the project. 相似文献