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151.
Robots have been envisaged as both workers and partners of humans from the earliest period in their history. Therefore, robots
should become artificial entities that can socially interact with human beings in social communities. Recent advances in technology
have added various functions to robots. The development of actuators and grippers show us infinite possibilities for factory
automation, and robots can now walk and perform very smoothly. All of these functions have been developed as solutions for
improving robot movement and performance. However, there are many remaining problems in the communication between robots and
humans. Communication robots provide one approach to the realization of embodied interfaces. Furthermore, the unsolved problems
of human–robot communication can be clarified by adopting the concept of subtractive methods. In this article, we consider
the minimal design of robots from the viewpoint of designing communication. By minimal design, we mean eliminating the nonessential
portions and keeping only the most fundamental functions. We expect that the simple and clean nature of minimally designed
objects will allow humans to interact with these robots without becoming uninterested too quickly. By exploiting the fact
that humans have “a natural dislike for the absence of reasoning,” artificial entities built according to minimal design principles
can extract the human drive to relate with others. We propose a method of designing a robot that has “character” and is situated
in a social context from the viewpoint of minimal design.
This work was presented in part at the 10th International Symposium on Artificial Life and Robotics, Oita, Japan, February
4–6, 2005 相似文献
152.
Okada T 《Analytical chemistry》2000,72(6):1307-1314
The interactions between ion-exchange resins and counterions consist of several mechanisms, such as ion-pair formation between active sites and counterions, specific adsorption, solvation changes, and double-layer accumulation. The double-layer accumulation of ions, which is a typical nonstoichiometric mechanism, is an important factor governing overall ion-exchange chromatographic retention when a major part of the stationary-phase surface is in contact with eluent flows. Nonporous stationary phases, where solutes are accessible to the surfaces by convection as well as by diffusion, possibly highlight this nonstoichiometric contribution through the coupling of a flow profile with an electrostatic potential function. The retention of ions on nonporous stationary phases has been interpreted by a model derived on the basis of the Poisson-Boltzmann equation including solvation change terms. Unusual retention behaviors have been confirmed only for anions, and can be explained by the model including the assumption that anions undergo solvation changes in a thin layer (approximately 5 nm thickness) at the vicinity of the stationary phase; the thickness should be a function of eluent flow rates. This strongly suggests that there is a difference in solvation nature between cations and anions. It can be inferred that water molecules interacting with polymer domains of the stationary phase behave like single molecules and cannot form a stable hydration shell around an anion as usually seen in bulk solution. 相似文献
153.
Using a 150-mum-thick CsLiB(6)O(10) crystal, we produced 100-fs, >200-nJ light pulses tunable between 175 and 180 nm by sum-frequency generation at a 1-kHz repetition rate with an all-solid-state laser system mixing the fourth harmonic of a femtosecond Ti:sapphire regenerative amplifier and the idler pulse from a traveling-wave optical parametric amplifier. 相似文献
154.
In X-ray crystallographic analysis, correct trial structures are refined by least-squares method. The detailed differential coefficients for the parameters of the calculated structure factor Fc(h) can not be found in any papers, textbooks, nor user's manual of several crystallographic computer systems. We describe, firstly, the basic expression of the structure factors, Fo(h) and Fc(h), anomalous dispersion terms of the structure factor, and then least-squares refining of magnitude of Fo(h) and Fo(h)2 for use in teaching, education and computer programming. Secondly we derive the differential terms of the structure factors, solve the normal equation by diagonal, block and full-matrix approximations, and apply these to the revised computer program LSBF in DS*SYSTEM. Several practical tests are performed for these differentiations. 相似文献
155.
Okada H Wakamatsu M Takano Y Nogawa M Morikawa Y 《Journal of Bioscience and Bioengineering》1999,88(5):563-566
Two xylanase genes (xyn1 and xyn2) were amplified by the polymerase chain reaction (PCR) technique from first-strand cDNA prepared from mRNA of Trichoderma reesei QM9414. The genes were located under the human cytomegalovirus gene promoter (CMVp) on copy-number-controlled plasmids (pTLxyn1 and pTLxyn2). When both plasmids were introduced into Schizosaccharomyces pombe, functional xylanases (XYN I and XYN II) were secreted by the recombinant yeasts. The secreted XYN I protein had a molecular mass of 21 kDa whereas XYN II was produced as two molecular forms with sizes of 21 and 28 kDa, the former being not glycosylated and the latter N-glycosylated. XYN I was secreted in the culture medium at a level of about 25 microg/ml and XYN II at about 170 microg/ml. The recombinant xylanases had the same characteristics with respect to the effects of temperature and pH on the enzyme activity as the native ones. 相似文献
156.
Spontaneous hydrolytic degradability of copolyesters having tetrahydropyran rings in their backbones
Homo- and copolyesters, containing 2,5-linked tetrahydropyran rings in their backbones, were prepared by cationic ring-opening polymerization of bicyclic lactones, 2,6-dioxabicyclo [2.2.2] octan-3-one ( 1 ), and its 4-methoxy-carbonyl and 4-methoxy-carbonyl and 4-benzyloxycarbonyl derivatives ( 3 and 4 ). Copolyesters, having pendant carboxyl groups, were derived from the copolymers containing 4 as one of the comonomers by the catalytic hydrogenolysis of the pendant benzyloxy–carbonyl groups. Copolyesters, containing both 2,5-linked and 2,6-linked tetrahydropyran rings in the main chains, were obtained by the copolymerization of 1 with 6,8-dioxabicyclo [3.2.1] octan-7-one ( 13 ), which is a structural isomer of 1 . Spontaneous hydrolytic degradability of these polyesters was investigated in a phosphate buffer solution (pH 7.5) at 27°C. The degradability of the polyesters markedly depended on the molecular structure: hydrophobic pendant groups retarded the hydrolytic degradation, whereas hydrophilic pendant groups accelerated it. In particular, a small amount of pendant carboxyl groups significantly enhanced the hydrolytic degradability of the copolyesters from 1 . Polyesters, containing 2,6-linked tetrahydropyran rings in their backbones, underwent hydrolytic degradation more readily than those entirely consisting of 2,5-linked tetrahydropyran rings. © 1994 John Wiley & Sons, Inc. 相似文献
157.
Properties of graphite prepared from boron-doped pitch as an anode for a rechargeable Li ion battery
Boron-doped graphites were derived from a naphthalene-based pitch mixed with para-xylene glycol (PXG) or dimethyl para-xylene glycol (DMPXG) as a cross-linking agent and three types of boron-containing compounds as a graphitization catalyst, and their anode performances were investigated. The structural analysis of the obtained graphites revealed that PXG functioned mainly as a two-dimensional cross-linking agent during the heat treatment process and DMPXG functioned partially as a three-dimensional. The average interlayer spacing decreased and lattice constant, a0, and graphitizability increased with increasing the amount of boron atoms added. The result indicated that the carbon atoms were replaced by boron atoms. The anode performance was improved by the enhancement of graphitizability. The structural parameters and anode performance of boron-doped graphites did not depend on the kind of boron-containing compounds but the amount of boron atoms added in pitch and the kind of cross-linking agent. 相似文献
158.
A story generation system based on dynamics of the mind is presented. Semantic theories until now avoided discussing a linkage of language with encyclopedic human knowledge. This paper attacks the problem of how to make clear the complicated, wide-ranging dynamics of the mind and how to connect it to language.
First, the background of this study is shown, in which our model of the mind, with both five levels along the concept formation process and eight domains according to the contents of mental activities, is surveyed.
Based on this model, then, the dynamics of mind are discussed, along an Aesop fable. A unit of data processing in the mind is called a "module," and the mental dynamics are considered as a chain activation of those modules, represented by a dynamic network. Next, a method for story generation is discussed. Propositional information of a sentence is embedded in a slot of activated, frame-structured modules, and the discourse structure of a generated story basically depends on the dynamic network. Both the chain activation and the generation processes are verified by experiments.
Lastly, residual problems of our research, a comparison with related research, and its applications are discussed.
This case study would be expected to give a basis to integrated systems for problem solving, natural language and image understandings, their generations, and intelligent robots. 相似文献
First, the background of this study is shown, in which our model of the mind, with both five levels along the concept formation process and eight domains according to the contents of mental activities, is surveyed.
Based on this model, then, the dynamics of mind are discussed, along an Aesop fable. A unit of data processing in the mind is called a "module," and the mental dynamics are considered as a chain activation of those modules, represented by a dynamic network. Next, a method for story generation is discussed. Propositional information of a sentence is embedded in a slot of activated, frame-structured modules, and the discourse structure of a generated story basically depends on the dynamic network. Both the chain activation and the generation processes are verified by experiments.
Lastly, residual problems of our research, a comparison with related research, and its applications are discussed.
This case study would be expected to give a basis to integrated systems for problem solving, natural language and image understandings, their generations, and intelligent robots. 相似文献
159.
R Pokharel K Hisano M Yasufuku K Ataka M Okada S Yoshimoto H Nakamura 《Canadian Metallurgical Quarterly》1998,28(12):1290-1294
Medically refracted patent ductus arteriosus (PDA) in an extremely low birth weight (ELBW) preterm (gestation 24 weeks 2 days) infant was successfully ligated under general anesthesia in the neonatal intensive care unit (NICU). Pharmacological agents are more effective to close PDA in preterm infants than in full-term infants, although within 48 h three doses of indomethacin were not sufficient to close PDA in this case. At the age of 69 h the infant developed severe symptoms including bradycardia, systemic hypotension, pulmonary hypertension, diastolic steal (reverse distal aorta flow velocity), and anuria. A PDA ligation was thus performed surgically at 72 h of age. General anesthesia and surgical stress were tolerated by this 531 g infant. Postoperatively all symptoms improved dramatically and the general conditions were stable. On the 38th day the endotracheal tube was extubated and on the 50th day nasogastric milk feeding was started. The oxygen supply was weaned on the 78th day. Growth and development until 6 months were within the normal range of very low birth weight infants. A surgical ligation as early as possible in medically refracted PDA in an ELBW infant is thus considered to be a safe and effective treatment. It prevents the development of further complications of cardiopulmonary vascular problems. Color Doppler echocardiography can reliably measure the PDA size, flow velocity, and hemodynamic changes of persistent PDA, even in tiny infants. 相似文献
160.
There is an ever-increasing demand for statistical information in health-care societies, and voluminous statistics are collected every year. When one needs information on survey results, it is generally not allowed to access the original data, and the summary tables are the most important source of information which can be shared. In order to store summary tables as a well-organized database and to perform flexible retrieval, a formal study has been made on the structure of summary tables. We introduce the notion of summary table scheme and define the operations called table transformation. A statistical database management system has been implemented based on the study. In our study, a statistical database is a collection of summary tables obtained from a survey. If a survey is conducted periodically, a database consists of all the tables obtained in the past. System utilities have been implemented for handling time-oriented information. 相似文献