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121.
Joint Accent Structure (JAS) is a construct that uses temporal relationships between different accents in a melodic pattern as indices of its complexity. The present study examines the role of different JASs in real time, attending to simple musical events. 39 adults with or without musical training were told to selectively attend to and synchronize finger taps with accents in 2 experiments that examined attentional tracking to musical patterns having a concordant or discordant JAS. Results indicate that tapping was more variable with discordant than with concordant JAS patterns, both with respect to produced inter-accent time periods and with respect to the phase of taps relative to accent onsets. These findings are interpreted in terms of real time attending and its control by event time structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
The surface of polyethylene was derivatized with ester, carboxylate, amino, hydroxyl, and phosphate functional groups. α, ω bifunctional alkanes, containing on one end a primary amine, were coupled to oxidized polyethylene through an amide linkage. Polyethylene was first oxidized with chromic acid, the carboxylate groups were converted to the acyl chloride with phosphorus pentachloride, and then reacted with a primary amine to give the covalently bound amide. The copposing ends of the bifunctional alkanes were the methyl, tertiary amine, ester, and hydroxyl groups. The ester was converted to the carboxylate by acid cleavage and the hydroxyl group converted to the phosphate by treatment first with phosphorus oxychloride and then aqueous base. Attenuated total reflection FTIR, XPS, and pH-dependent contact angle wetting were used to characterize the surfaces. The FTIR data were used to confirm the formation of the amide and to detect an undesired carboxylate/ammonium ion complex formed in the presence of trace amounts of water. XPS data were used to confirm expected changes in elemental composition and to provide quantitative estimates of the yields. Oxidation of the polyethylene introduced 5 × 1014 carboxylate groups/cm2 in the 25 Å XPS sampling depth. Of these, up to 98% could be converted to the amide. The advancing contact angle data confirmed the acid/base behavior of the functional groups. 相似文献
123.
Kinicki Angelo J.; Hom Peter W.; Trost Melanie R.; Wade Kim J. 《Canadian Metallurgical Quarterly》1995,80(3):354
Two studies examined whether the accessibility of performance prototypes influences performance appraisals. Pilot studies revealed students used performance prototypes when rating instructor performance. Study 1 manipulated the accessibility of these prototypes and the time delay of performance ratings. Results showed no effect of the prime on rating error and accuracy; however, discrimination accuracy decreased over time and recognition bias became more conservative. Study 2 manipulated prototype accessibility and type of rating stimuli (videotape vs. vignette). Rating accuracy and recall were higher for vignette than videotape stimuli, and only those participants exposed to the vignette exhibited priming effects. Results supported transfer-appropriate processing and implied that cognitive primes may have a stronger effect on performance ratings based on "paper-people" than videotaped stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
124.
Dusts,scale, slags,sludges... Not wastes,but sources of profits 总被引:3,自引:0,他引:3
Peter J. Koros 《Metallurgical and Materials Transactions B》2003,34(6):769-779
Historically, the steel industry has focused on the need for and the many benefits of recycling steel that is discarded either
in its own or in its customers’ manufacturing processes, as well as in recovery and reuse of steel scrap that arises after
the product has served its intended purpose. In fact, modern steelmaking relies on the use of recycled iron units for at least
half of its production.
The other side of the story is the fate of the non-steel by-products (e.g., oxide dusts, sludges, scales, slags, spent refractories and the contained “low grade” energy units that are generated as
natural adjuncts to iron and steelmaking processes). These valuable by-products often are classified as “wastes” and are discarded
to landfills, at significant cost, although in reality they offer significant potential for cost savings or profit if reintroduced
into the industrial arena via well planned programs. Examples of such instances will be presented, including energy credit issues, in the hope of pointing
the way for future expansion of benefits from these opportunities.
Preparing for a challenge and honor such as the Howe Memorial Lecture, one has to stand in awe of the accomplishments of the
predecessor we honor in this forum. He worked in the early days of our industry without the benefits of the many technological
improvements he and his successors brought to play as the years went by. John Stubbles, in his Howe Memorial Lecture in 1997,[1] presented a masterful and entertaining biography of Howe and his very active and prolific life. Perhaps the most telling
quotation he attributed to Howe is very pertinent to the topic we will address presently: “Metallurgy lives by profit, not
logic,” to which I would like to add a comment that bears on the topic of this lecture from the 1991 Howe lecturer, my friend
and mentor Bill Dennis, “Where there is muck, there is money.”
There are numerous examples of “one hand washes the other” in this business; that is, of the synergism between needs and capabilities.
We will address some of these situations, such as in a new process under development for dezincing of post consumer scrap,
and in the use of iron units in by-product oxides and recycling of ladle slags and of spent refractories.
Peter J. Koros, the Iron and Steel Society’s 77th Howe Memorial Lecturer (2001), is Principal of Koros Associates, Inc. (Pittsburgh,
PA), a consultancy he founded following retirement from the former LTV Steel Company where he worked for nearly 41 years,
retiring as Senior Research Consultant. He earned the Bachelor of Science degree in Metallurgical Engineering from Drexel
University, and his master’s and doctoral degrees in Metallurgy from the Massachusetts Institute of Technology (MIT). In 1958,
he joined Jones and Laughlin Steel (which became LTV Steel Company), where he held positions in research (Director, Process
Metallurgy), Technical Services and Quality Control, with most activities focused on steelmaking and related areas.
He was responsible for J&L’s development work in injection technology for desulfurization of hot metal and steel, was the
inventor of the patented co-injection concept now in use worldwide, and had the lead role in LTV Steel’s programs for degalvanizing
scrap and for recovery and utilization of by-product oxides. He led the AISI Opt-In program for degalvanizing scrap and the
LTV-USS pilot program for processing “by-product” oxides. Koros has authored more than 75 publications and presentations,
and holds eight U.S. patents, the latest issued in 2000.
Dr. Koros was elected a Distinguished Member and Fellow of the ISS in 1984 and a Fellow of ASM International in 1988. Other
honors include the ISS Distinguished Service Award (1998), ISS Electric Furnace Honorable Mention Citation (1987), International
Magnesium Association Design and Applications Award (1978), AISI Gold (1977) and Silver (1969) Medals, ISS Herty (1963), McKune
(1963), and Toy (1962) Awards.
Koros served on the Technical Advisory Committee of the AISI-DOE Direct Steelmaking Program and its follow-on Waste Oxide
Recycling Program. He was chairman of the AISI Task Force on Degalvanizing Steel Scrap and of the Industrial Advisory Panel
to the Argonne Lab-MRI Program on Dezincing Steel Scrap. The 2001 Howe Memorial Lecture, titled “Dusts, Scale, Slags, Sludges
... Not Wastes But Sources of Profits,” as well as an invited Keynote Lecture for an International Recycling Conference in
Sweden (June 2002, “Iron Units in Search of a Home: New Steel”) were based on the experience from these programs.
Koros has been an active member of the ISS Advanced Technology Committee for which he participated in and chaired several
symposia, including New Melting Technologies II (October 2002) and the first New Melting Technologies Symposium (1997). He
was Director of the ISS 2000 Short Course on Injection Technology, a lecturer in the 2000 ISS/AISI Course on BOF Steelmaking,
lead Co-chairman for the Elliott Symposium (1990), and Chairman of the Program Committee for the Fifth International Iron
and Steel Congress (1986). Dr. Koros served on the Industrial Advisory Board of MIT’s Materials Processing Center (1995–98)
and the AISI’s Iron and Steel Research Subcommittee (1976–86.) He was chairman of the ISS National Science Foundation Advisory
Committee, the Advisory Council of the U.S. Bureau of Mines Generic Minerals Technology Center for Pyrometallurgy Research
(1983–85), and of the Advisory Board for Carnegie Mellon University’s Center for Iron and Steel Research, for which he served
as chairman (1991–1992). Service included participation in the NRC-NAS Alternative Energy and Development Strategy Study (1989–90.)
Koros was very active in the creation of the ISS, having served as Chairman of the predecessor TMS Iron and Steel Division
in 1972–73 and on the AIME Board of Directors (1974).
Professional Society memberships: ISS (elected Distinguished Member and Fellow, Life Member), TMS (Senior or Life Member),
ASM International (elected Fellow, Life Member), and AISE. 相似文献
125.
Peter Stephenson 《Computer Fraud & Security》2003,2003(1):17-19
In last month’s column we started the correlation process. This early work simply looked at individual pieces of evidence as they might relate to other pieces of evidence. However, there are some potential pitfalls if we stop here. First, digital evidence can be ambiguous. In other words, we can see the same event reported by various sources in various ways. Are we really looking at the same event, or are we looking at different ones? The second issue is that events may be reported in unusual ways leading the analyst to believe that the event occurred multiple times when, in fact, it did not. We need processes to analyze all the events that are reported and to help us to understand the actual data that we are seeing. Fortunately, we actually have two: normalization and deconfliction. Those two processes will be the topics of this month’s offering. 相似文献
126.
Peter Speier 《Journal of Electronic Materials》1991,20(12):993-999
The technological limits for ultra high speed devices are now rapidly expanding due to the use of quantum well (QW) materials.
This new class of materials gives the opportunity of tailoring materials parameters by controlling geometries on an atomic
scale. They look very promising as materials for lasers, detectors and transistors suitable even above 10 Gb/s. It will be
demonstrated that state of the art MQW structures can be realized in both material systems, InGaAsP/InP and InGaAlAs/InP.
Parallel lateral laser structures (e.g. SIBH, BRS and TBH) have been designed to take full benefit of QW technology. Ultimate reduction of parasitics, whilst using
potential low cost fabrication technologies is the basis for achieving high bitrate (10 Gb/s) MQW lasers, even with the stronger
damping in QW material. Using the DFB-SIBH laser structure 10 Gb/s large signal experiments are successfully performed with
bulk, MQW and SLMQW lasers. Extremely low fall times of 44 ps are achieved. Additional MQW based improvements are observed
such as: −3 times higher differential gain, increased output power (>110 mW), 2.5 times lower chirp (Δλ−20dB = 0.40 nm at 10 Gb/s modulation), and 2 dB gain in power budget at 10 Gb/s digital transmission. 相似文献
127.
Totterdell Peter; Spelten Evelien; Smith Lawrence; Barton Jane; Folkard Simon 《Canadian Metallurgical Quarterly》1995,80(1):43
Although regulations on work hours usually include a minimum weekly rest period, there is little empirical evidence concerning recovery from work. Shift-working nurses (N?=?61) used a handheld computer for 28 days to complete self-ratings, cognitive-performance tasks, and a sleep diary. Many measures were worse on rest days that followed a night shift rather than a day shift and tended to be worse on 1st rest days compared with subsequent rest days. Alertness was lowest on the 1st rest day following a night shift. Social satisfaction was better on workdays that were preceded by 2 rather than 1 rest day. Reaction time (RT) decreased over consecutive night shifts and tended to increase over rest days following night shifts. The results are interpreted as being consistent with the combined adaptive costs of fatigue and adjustment to and from a nocturnal routine. The practical implications for scheduling rest days are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
128.
Peter Rez 《Journal of research of the National Institute of Standards and Technology》2002,107(6):487-495
To calculate the intensity of x-ray emission in electron beam microanalysis requires a knowledge of the energy distribution of the electrons in the solid, the energy variation of the ionization cross section of the relevant subshell, the fraction of ionizations events producing x rays of interest and the absorption coefficient of the x rays on the path to the detector. The theoretical predictions and experimental data available for ionization cross sections are limited mainly to K shells of a few elements. Results of systematic plane wave Born approximation calculations with exchange for K, L, and M shell ionization cross sections over the range of electron energies used in microanalysis are presented. Comparisons are made with experimental measurement for selected K shells and it is shown that the plane wave theory is not appropriate for overvoltages less than 2.5 V. 相似文献
129.
This article describes the development and validation of scales to measure clients' outcome optimism, perceived progress, and self-agency related to change in problems presented in therapy. In Study 1, initial confirmatory and subsequent exploratory factor analyses (N?=?257) identified effort and persistence as an additional unique factor and guided selection of items to measure the 4 constructs. In Study 2, confirmatory factor analysis of the revised scales with a new sample (N?=?93) confirmed the measurement model. Results of convergent and discriminant validity analyses generally were in the predicted directions. The Perceived Progress scale demonstrated criterion validity with changes in dyadic adjustment and family functioning. The Outcome Optimism and Self-Agency scales showed variability in their relationship to the Perceived Progress scale over the first 3 sessions of therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.