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41.
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
42.
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
43.
44.
We consider a system defined as the product of a finite set of periodic systems on cyclic groups. It is of interest to determine if certain subgroups and unions of subgroups of the state set are reachable from a specified initial state, and in particular to determine the computational complexity of verifying such reachability. These questions are motivated by certain problems that arise in the modelling and control of discrete event systems and certain forms of periodic scheduling. Our main result is that deciding whether or not the union of a certain set of subgroups is reachable or not is NP-complete. 相似文献
45.
Nickel molybdate catalysts used in several different upgrading reactions of coal-derived materials from low-rank Australian coals have been regenerated and their activity assessed using a number of physical and chemical techniques. Regeneration of spent coked catalysts for 20 hours in air at 450°C was sufficient to restore chemical hydrogenation activity to catalyst used for pre-asphaltene, asphaltene and oil upgrading, provided poisoning of the catalyst surface by other impurities, principally chlorine-containing molecules, had not occurred. 相似文献
46.
Experimental studies on phase equilibria in the multicomponent system PbO-ZnO-CaO-SiO2-FeO-Fe2O3 in air have been conducted to characterize the phase relations of a complex slag system used in commercial lead oxidation
smelting. The liquidus in the pseudo-ternary section ZnO-“Fe2O3”-(PbO + CaO + SiO2) with the CaO/SiO2 weight ratio of 0.35 and the PbO/(CaO + SiO2) weight ratio of 5.0 has been constructed using results of over 100 high-temperature equilibration and quenching experiments
followed by electron probe X-ray microanalysis. The liquidus in this pseudoternary section contains primary phase fields of
spinel (zinc ferrite) Zn
x
Fe3−x
O4+y
, zincite Zn
u
Fe1−u
O, melilite Pb
v
Ca2−v
Zn
w
Fe1−w
Si2O7, hematite Fe2O3, magneto-plumbite PbFe10O16, and dicalcium silicate Ca2−t
Pb
t
SiO4. The laboratory results are compared with the slags obtained from an industrial reactor. 相似文献
47.
48.
Peter P. Mykytyn Jr. 《AI & Society》1989,3(2):133-141
Expert systems have been concerned with applications dealing with medical diagnosis, mineral exploration, and computer configuration, with some efforts relatively successful in achieving results at least as good as human experts. Today, much is being written about these systems and managerial decision-making activities in organizations and the positive impact that they can have in these situations. However, it appears that expert systems could become somewhat of a panacea for some organizational ailments as research, development, and marketing of them continues at a fast pace. What may be forgotten in this technological thrust is the individual decision maker and his/her unique style of decision making which could affect acceptance and use of these systems. Another important consideration is the attitude people have toward computers and computer systems, which along with decision-making styles could certainly affect expert system effectiveness and ultimate success in organizations. This paper provides a discussion of potential problems that could occur regarding individual decision making and attitudes and their relationships to these systems. 相似文献
49.
Thomas Stieglitz Martin Schuettler Klaus Peter Koch 《IEEE engineering in medicine and biology magazine》2005,24(5):58-65
In the following article, the technologies to fabricate polyimide-based thin and flexible substrates with monolithically integrated electrode arrays and printed circuit boards (PCB) for hybrid electronic assemblies as well as an assembling technique that connects bare electronic dice with flexible PCBs are presented. The concept of modular, flexible biomedical microsystems as neural prostheses is introduced in general and described in detail in three examples. A cuff electrode with integrated multiplexer circuitry and standard implantable cables represents the combination of microtechnology with precision mechanics; a sieve electrode used as an implant in peripheral nerve regeneration studies demonstrates the next level of integration density but still uses a cable connection; and last, joint effort to fabricate the demonstrator of a vision prosthesis that is completely implantable in the eye with a wireless link for energy supply and data transmission is presented. System design, hybrid assembling technology, and flexible multilayer encapsulation using parylene and silicone rubber are the key components for creating a new generation of neural prostheses for complex and challenging new applications. 相似文献
50.
The dependence of the cetane number of hydrotreated light cycle oil on chemical composition has been investigated. Cetane number was related to hydrogen content and aromaticity. The latter was determined by high performance liquid chromatography and also by carbon-13 n.m.r. spectroscopy. Specific correlations were developed in each case and a regression coefficient of 0.99 and a standard error of 1.25 were obtained for the best case. The usefulness of predicting cetane number from fuel composition is discussed. 相似文献