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981.
Stefan Roth Stefan Hirschberg Christian Bauer Peter Burgherr Roberto Dones Thomas Heck Warren Schenler 《Annals of Nuclear Energy》2009
This paper outlines the approach to the evaluation of sustainability of current and future electricity supply options of interest for a major Swiss utility Axpo Holding AG. The motivation behind this effort has been to provide a solid basis for a state-of-the-art interdisciplinary assessment and use this framework within a dialog with a wide spectrum of stakeholders. The development and implementation of the methodology was coordinated by Axpo in co-operation with the Paul Scherrer Institut (PSI) and other scientific institutions. 相似文献
982.
Roberto Marrero-Ortiz Jing Han Aaron M. Lynne Donna E. David Mary E. Stemper Doris Farmer William Burkhardt Rajesh Nayak Steven L. Foley 《Food research international (Ottawa, Ont.)》2012,45(2):962-967
Salmonella enterica is a pathogen of humans and animals, and is one of the most frequent causes of bacterial foodborne illness worldwide. People consuming contaminated foods or working with infected livestock have the potential to become infected with Salmonella and may require antimicrobial therapy. Antimicrobial resistance in Salmonella has become a problem worldwide due in part to the inappropriate use of antimicrobial agents in human and veterinary medicine. In this study, forty-five Salmonella isolates from diagnostic fecal samples of Wisconsin dairy cattle were serotyped and characterized by antimicrobial susceptibility testing using agar disk diffusion, antimicrobial resistance gene detection by PCR, plasmid analysis and conjugation studies. The predominant serovars detected were Kentucky, Newport, Typhimurium, Cerro, Dublin and Montevideo. Over half (51%) of all isolates were resistant to at least one antimicrobial agent, and 29% were resistant to 8–10 drugs. The most commonly observed resistance phenotypes were to streptomycin (44%), tetracycline (42%), sulfisoxazole (40%), chloramphenicol (35%), ampicillin (33%), and cefoxitin (33%). When resistance was detected phenotypically, a corresponding resistance gene was detected 86.2% of the time. Plasmids ranging in size from < 8 to 165 kb were detected in 45% of the isolates. A greater understanding of the factors associated with antimicrobial resistance in Salmonella should provide insights into the factors that contribute to the development of resistant pathogens during dairy production, which in turn can lead to strategies to minimize the spread of antimicrobial resistant Salmonella in the food supply. 相似文献
983.
984.
Nadia BarberoClaudia Barolo Domenica Marabello Roberto BuscainoGiuliana Gervasio Guido Viscardi 《Dyes and Pigments》2012,92(3):1177-1183
The synthesis, spectroscopic characterization, and X-ray crystal structure of [4-(2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-ylazo)-phenyl]-methanol azodye are reported. A 37-47 nm bathochromic shift has been observed by comparison with analogous azodyes where diethylamino or dimethylamino groups act as donor moiety in agreement with the larger electronic donating properties of julolidine. The azobenzene skeleton adopts a planar trans-configuration and intra- and inter-molecular hydrogen bonds have been detected. A correlation between the spectroscopic and the molecular features has been attempted. 相似文献
985.
Gabriella Bretti Roberto Natalini Benedetto Piccoli 《Archives of Computational Methods in Engineering》2007,14(2):139-172
We consider a mathematical model for fluid-dynamic flows on networks which is based on conservation laws. Road networks are
studied as graphs composed by arcs that meet at some nodes, corresponding to junctions, which play a key-role. Indeed interactions
occur at junctions and there the problem is underdetermined. The approximation of scalar conservation laws along arcs is carried
out by using conservative methods, such as the classical Godunov scheme and the more recent discrete velocities kinetic schemes
with the use of suitable boundary conditions at junctions. Riemann problems are solved by means of a simulation algorithm
which processes each junction. We present the algorithm and its application to some simple test cases and to portions of urban
network. 相似文献
986.
Ida Cariati Laura Masuelli Roberto Bei Virginia Tancredi Claudio Frank Giovanna DArcangelo 《International journal of molecular sciences》2021,22(12)
Niemann–Pick type C (NPC) disease is an autosomal recessive storage disorder, characterized by abnormal sequestration of unesterified cholesterol in the late endo-lysosomal system of cells. Progressive neurological deterioration and the onset of symptoms, such as ataxia, seizures, cognitive decline, and severe dementia, are pathognomonic features of the disease. In addition, different pathological similarities, including degeneration of hippocampal and cortical neurons, hyperphosphorylated tau, and neurofibrillary tangle formation, have been identified between NPC disease and other neurodegenerative pathologies. However, the underlying pathophysiological mechanisms are not yet well understood, and even a real cure to counteract neurodegeneration has not been identified. Therefore, the combination of current pharmacological therapies, represented by miglustat and cyclodextrin, and non-pharmacological approaches, such as physical exercise and appropriate diet, could represent a strategy to improve the quality of life of NPC patients. Based on this evidence, in our review we focused on the neurodegenerative aspects of NPC disease, summarizing the current knowledge on the molecular and biochemical mechanisms responsible for cognitive impairment, and suggesting physical exercise and nutritional treatments as additional non-pharmacologic approaches to reduce the progression and neurodegenerative course of NPC disease. 相似文献
987.
Paulo Roberto Saraiva Cavalcante Maria do Socorro Rodrigues Marcel Felipe Sousa Barroso Ricardo Barbieri Carmen Lúcia Martins Serra Rosana Carla Alves Oliveira 《Lakes & Reservoirs: Research and Management》2007,12(1):35-42
The diel variation of limnological parameters, measured in Boa Esperança Reservoir, Brazil during the rainy period, exhibited small temperature gradients characterized by an increase in temperature by midday, followed by a partial homogenization of the water column in the night and the early morning. The result was an increase in the epilimnion to a depth of 17 m. The pH and dissolved oxygen concentrations showed higher values at the surface, with the occurrence of anomalies (concentrations higher than at the surface) of the latter variable in the epilimnion, probably as a result of the activity of primary producers and/or losses of oxygen to the atmosphere. The chemical forms of iron in the reservoir exhibited increasing concentrations with depth, as a result of an increase in the concentration of seston and/or accentuated reduction of the levels of oxygen in the bottom layers. The reduction of Fe3+ to Fe2+ in the bottom water layers in the reservoir, in addition to the primary production process in the epilimnion, could explain the increased phosphorus in the bottom water layer. The concentrations of nitrogen compounds did not exhibit relevant changes or a defined evolution profile, except for nitrate, which showed an outstanding increase in the bottom water layers, suggesting it could be an important nitrogen source for primary producers. Although not unequivocal, these data suggest that ecosystem instability in Boa Esperança Reservoir is the product of short diel thermal variations, and the reduced input of allochthonous materials and nutrients from local catchment. These conditions guarantee the oligotrophic status of Boa Esperança Reservoir for the present time. 相似文献
988.
The effect of recycling the unconverted bottom on catalyst deactivation as a way to improve the hydrocracking conversion of heavy oil was analyzed using the experimental information obtained in a steady-state ebullated bed reactor. The recycle contained different amounts of partially converted (aged) material. Four sets of experiments were performed to demonstrate that after five passes through the reactor, the reactivity of the unconverted material decreased by 15% and its impact on catalyst deactivation increased by 30%. The results indicated that the higher the conversion, the lower is the reactivity and the higher is the catalyst deactivation. The production of an insoluble and refractory to convert material imposes a limit on the recycling benefit. 相似文献
989.
Amino acid profiles of carotenoproteins extracted from fermented and non-fermented shrimp waste were analysed. Fermented carotenoproteins were hydrolysed with a protease and a combination of a protease and a lipase. Essential amino acids in fermented and non-fermented carotenoproteins were 49% and 47%, respectively, with respect to total amino acids. The highest carotenoprotein hydrolysis (900 and 66 mg/g soluble protein and total carotenoids, respectively) was obtained by a combination of 15 proteolytic units together with 10 lipolytic units. The most efficient treatment using only protease was obtained with 15 proteolytic units (852 and 48 mg/g of soluble protein and total carotenoids, respectively). A relatively protein-free form of astaxanthin derived from shrimp waste carotenoproteins may be of interest for applications in salmon culture, and in natural health products and cosmetics. Furthermore, fermented carotenoproteins could be used in human and animal diets due to their high essential amino acids concentration. 相似文献
990.
Pablo A. Fiorito Fernanda F.C. Bazito Gerard Froyer Roberto M. Torresi 《Electrochimica acta》2008,53(25):7396-7402
The electroformation of silicon oxide was performed in two room temperature ionic liquids (RTIL), 1-butyl-3-methyl-imidazolium bis(trifluoromethane sulfonyl) imide (BMITFSI) and N-n-butyl-N-methylpiperidinium bis(trifluoromethane sulfonyl) imide (BMPTFSI). This phenomenon was studied by electrochemical techniques and it was observed that the oxide growth follows a high-field mechanism. X-ray Photoelectron Spectroscopy experiments have shown that a non-stoichiometric oxide film was formed, related to the low water content present in both RTILs (<30 ppm). The roughness values obtained by using AFM technique of the silicon surface after etching with HF was 1.5 nm (RMS). The electrochemical impedance spectroscopy at low frequencies range was interpreted as a resistance in parallel with a CPE element, the capacitance obtained was associated with the dielectric nature of the oxide formed and the resistance was interpreted considering the chemical dissolution of the oxide by the presence of the TFSI anion. The CPE element was associated with the surface roughness and the very thin oxide film obtained. 相似文献