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951.
Diffusion induced grain boundary migration (DIGM) was observed to occur in a Ni-48.5 wt pct Cu alloy during oxidation at 450
°C, 500 °C, 600 °C, and 707 °C in air. The DIGM zones are Cu enriched. A Ni depleted zone, consisting of small recrystallized
grains, formed in the matrix beneath the metal-oxide interface during oxidation at 600 °C and 707 °C. This process is referred
to as oxidation-induced recrystallization (OIR). Growth of the small OIR grains was observed to be associated with Cu-rich
DIGM. No Cu-rich DIGM was found in the same alloy when annealed in Ar at 707 °C. Oxidation of this alloy in air resulted in
the formation of a duplex oxide: an inner NiO layer and an outer CuO layer. The NiO layer was observed to grow at a faster
rate than the CuO layer. The occurrence of Cu-rich DIGM is interpreted in terms of this preferential oxidation of Ni. 相似文献
952.
953.
Benson Janette B.; Cherny S. S.; Haith Marshall M.; Fulker David W. 《Canadian Metallurgical Quarterly》1993,29(3):434
Assessed infant predictors of adult IQ with same-sex infant twins (114 pairs) and their parents. The midtwin–midparent design permits the rapid assessment of infant measures to predict later behavior, because the midparent score serves as a proxy for the infant's potential score at maturity. At 5, 7, and 9 mo, Ss were observed on the Fagan Test of Infant Intelligence, hand preference, vocalizations, selected Bayley Scales of Infant Development items, and a modified Bayley Infant Behavior Record. At 8 mo, Ss received the Visual Expectation Paradigm and an auditory discrimination task. Their parents received the Wechsler Adult Intelligence Scale—Revised (WAIS—R). Some infant measures, indicative of information processing, language ability, and temperament, predicted midparent IQ. This study extended and partially replicated findings from a previous midtwin–midparent cohort (L. F. DiLalla et al; see record 1991-04066-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
954.
The authors discuss the Macintosh Programmer's Workshop (MPW), a Macintosh development environment that includes a comprehensive set of programming tools and handles several languages. It also combines the graphical interface common to all Macintosh applications, a command language similar to the Unix shell languages, and Smalltalk's immediate execution of commands in any window. They focus on the program-development environment rather than on the tools in that environment. They give the history of MPW, and describe its design goals. The bulk of the article is a discussion of MPW's design 相似文献
955.
Y-Ba-Cu-O films with different surface treatments have been studied by photoelectrochemical and XPS measurements. The influence of etching by bromine in ethanol of these films has been followed by means of the electrochemical oxidation of ferrocene in an aprotic electrolyte. From the dependence of dark and photocurrent on etching time it is concluded that Y-Ba-Cu-O thin films on LaAlO3 are covered by a 1, 1nm thick nonstoichiometric surface layer. The cathodic polarization of Y-Ba-Cu-O at -0,9 V vs. Ag/AgCl in acetonitrile/0,1 M lithium perchlorate leads to the formation of a lithium-containing, oxygen-enriched surface layer. The photoelectrochemical response of the reduced films is similar to that of cuprous oxide and passive layers on copper. 相似文献
956.
J.W.C. de Vries 《Thin solid films》1987,150(2-3):209-215
The resistivity of thin nickel films is studied as a function of temperature from 4 to 320 K. Both as-deposited and heat-treated samples with thicknesses ranging from 10 to 80 nm are studied. The resistivity can be analysed taking only grain boundary scattering into account, using the theory of Mayadas and Shatzkes. The bulk residual resistivity of the as-deposited films appears to be dominated by grain boundary scattering. No clear evidence for surface scattering could be found. 相似文献
957.
W. SCHöNWELSKI F. HABEREY R. LECKEBUSCH M. ROSENBERG K. SAHL 《Journal of the American Ceramic Society》1986,69(1):7-9
Solid Solutions with the magnetoplumbite structure in the System LaMgAl11 O19 -LaMgGa11 O19 -LaMgFe11 O19 were studied by X-ray diffractometry of sintered samples. Complete miscibility exists in the subsystem LaMgAl11 O19 -LaMgGa11 O19 and in a narrow adjacent ternary area with low iron content. In the other subsystems and in the major part of the ternary field, a magnetoplumbite phase occurs together with other compounds. 相似文献
958.
By integrating lithography and self‐assembly via electrohydrodynamic instabilities, Russel and co‐workers are able to guide initially flat polymer films to evolve into periodic arrays of pillars over regions much greater in extent than their natural domain sizes, as detailed on p. 1992. Novel structures that involve a combination of linear ridges and pillars are also produced, mainly as as result of the dynamic merging among preformed pillars. To pattern thin polymer films via electrohydrodynamic instabilities, we design and utilize two different kinds of mask patterns to guide pillars into alignment over regions much greater in extent than their natural domain sizes. First, narrow protruding ridges that intersect to form regular patterns on the mask trigger the growth of pillars beneath. Later, square and triangular packings of pillars develop in the regions enclosed by those ridges, preserving the registry from one domain to the next over a much larger area than within individual domains in unpatterned portions of the mask. Second, small square protrusions that are prealigned into a large regular array on the mask guide the formation of square packings of pillars in domains that conform to the mask, forming a large array of pillars. Novel structures involving a combination of linear ridges and pillars are also produced mainly due to the dynamic merging among preformed pillars. Finally, we find vertex symmetry of the mask pattern is necessary for generating and preserving ordered patterns on the polymer film. 相似文献
959.
Text planning is traditionally done as a separate process, independent of linguistic realization. However, I show in this paper that it is essential for a text planner to know the linguistic consequences of its actions. The choice of how to realize an element affects how much information is conveyed (e.g., “Floyd arrived safely in Boston” vs. “Floyd landed safely at Logan”) and what other information can be added (e.g., “Peter was deciding for an hour” vs. *“Peter made a decision for an hour”). The choice of realization also affects how the relative salience of the elements being expressed will be perceived (e.g., “The green car is in the garage” vs. “The car in the garage is green”). I have defined an intermediate level of representation for text planning, called the Text Structure. It is an abstract linguistic level that reflects germane linguistic constraints while abstracting away from syntactic detail. This representation allows the text planner to have greater control over the decisions, so that it can take advantage of the expressiveness of language to convey subtleties of meaning. More importantly, the Text Structure allows the generation process overall to be incremental, since it ensures that the text plan being composed will always be expressible in the language. La planification de textes est habituellement réalisée séparément, sans tenir compte de la réalisation linguistique. Cependant, ľauteur demontre dans cet article qu'il est essentiel à un planificateur de textes de connai̊tre les conséquences linguistiques de ses actions. Le choix de la méhode de réalisation ?un élément influe sur la quantité?informations qui est transmise (par ex.: 〈〈 Floyd est arrivé sain et sauf à Boston 〉〉 et 〈〈 Floyd a atterri sain et sauf àľaéroport Logan 〉〉) et sur quelle autre information peut ětre ajoutée. Le choix de la méthode de réalisation influe également sur la façon dont les caractères saillants des ééments qui sont exprimés seront perçus (par ex.: 〈〈 la voiture verte est dans le garage 〉〉 et 〈〈 la voiture dans le garage est verte 〉〉). L'auteur a défini un niveau intérmediaire de représentation pour la planification de textes qu'il a appelé structure de texte. Il; s'agit ?'un niveau linguistique abstrait qui refléte les contraintes linguistiques appropriées tout en s'éloignant du détail syntaxique. Cette représentation permet au planificateur de textes ?avoir un meilleur contrǒle des décisions, et done de tirer profit de la force ?expression du langage afin de tenir compte des subtiliés de sens. Plus important encore, la structure de texte permet au processus de génération ?ětre incrémentiel, car elle s'assure que le plan de texte en voie de composition soit toujours exprimable dans le langage. 相似文献
960.