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101.
"Six Macacus cynomolgus monkeys were trained in a shock-avoidance situation while under the influence of reserpine. Three sessions of 60 trials were given a week apart. Subsequent acquisition of the habit was retarded." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Isaac C. Sanchez 《Polymer Engineering and Science》1984,24(2):79-86
An abbreviated review of the current state of knowledge of polymer interfacial phenomena is given. Classical thermodynamics treats the interfacial zone (the interphase) as a “black box” and yields rigorous relationships among interfacial quantities. A recent reformulation of interphase thermodynamics, which eliminates the use of a Gibbs dividing surface, is shown to be an invaluable tool for investigating interfacial properties. Microscopic theories, such as the gradient theory, yield more details about what is in the black box, but the information is only approximate. The gradient theory has been used to: (1) relate the surface tension of a polymer liquid to its isothermal compressibility, (2) develop a quantitative theory of polymer liquid surface tension, and (3) determine the interfacial tension between two immiscible polymer liquids. The gradient theory will be shown to be in harmony with the microscopic theory of Helfand and co-workers although the latter treats polymer interfaces from a completely different point of view. 相似文献
103.
We have analyzed a large set of data in the literature as well as new data of our own to provide an improved equation of state of solid para-hydrogen and ortho-deuterium, with pressures ranging from 0 to 25 kbar (at the melting line). Results, including pressure, bulk modulus, and thermal expansion, are tabulated for a dense set of molar volumes as a function of temperature.Partial financial support provided by the Stichting FOM. 相似文献
104.
A study of the transient liquid phase bonding process applied to a Ag/Cu/Ag sandwich joint 总被引:6,自引:0,他引:6
Isaac Tuah-Poku M. Dollar T.B. Massalski 《Metallurgical and Materials Transactions A》1988,19(3):675-686
Transient liquid phase (TLP) bonding is a process currently used for joining heat resistant alloys, for example nickel- and
cobalt-based superalloys. It involves the formation of a liquid layer between two adjoining pieces and the formation of a
solid bond as the liquid disappears during annealing at a suitable constant temperature. In the present study, a model Ag/Cu/Ag
sandwich joint associated with a simple eutectic phase diagram was used to study the different stages of this process. The
results confirm that the TLP bonding is a diffusional process occurring in clearly distinctive stages. The two most important
stages are the widening and homogenization of the previously dissolved liquid interlayer, and the subsequent solidification
and shrinking of the interlayer. Whereas the former stage involves diffusional processes both in the liquid phase and in the
adjoining solids, the latter is controlled mainly by the diffusion in the solid phase. A modeling approach has been explored
which shows that in most eutectic systems there exists an optimal bonding temperature corresponding to the shortest time needed
for complete solidification. The results of a study on a Ag/Ag-20 wt pct Cu/Ag sandwich joint provide evidence that the use
of an alloy close to the eutectic composition as an interlayer material shortens the TLP process substantially. 相似文献
105.
Andrew M. Bailey Laura Pajak Isaac R. Fruchey Cristopher A. Cowan Peter A. Emanuel 《Journal of The Association for Laboratory Automation》2003,8(6):113-120
The events that occurred following the mailing of Bacillus anthracis-laced envelopes through the postal system has highlighted the need to perform biological screening on large numbers of environmental samples. High-throughput screening that relies on integrated robotic systems to speed analysis has been undertaken to handle the surge in samples requiring testing in events involving weapons of mass destruction. These automated screening systems require DNA extraction methods capable of handling environmental samples that contain inhibitors and have target organisms at low concentrations. This study describes the development of a method for the detection of the biological warfare agent simulants Erwinia herbicola and Bacillus subtilis var. niger spores using paramagnetic bead-based resin with an automated liquid handler and environmental samples. 相似文献
106.
T Klausen L Breum HA S?rensen S Schifter B Sonne 《Canadian Metallurgical Quarterly》1993,52(3):205-208
Nine male marathon runners were investigated during habitual training (week 0), after 3 weeks of training break (week 3), and after 2 weeks (week 5) and 4 weeks (week 7) of retraining. Maximal oxygen uptake, body fat (BF), and plasma levels of 25(OH)D3, 1,25(OH)2D3, parathyroid hormone (PTH), calcitonin (CT), albumin, and albumin-corrected calcium were determined throughout weeks 0-7. The maximal oxygen uptake decreased after training break and increased during retraining (P = 0.002). BF did not change significantly. Plasma 1,25(OH)2D3 was elevated after training break and decreased after 2 and 4 weeks of retraining [week 0: 44.0 +/- 3.7 (SEM) pg x 1(-1); week 3: 52.4 +/- 6.0 pg x 1(-1); week 5: 42.0 +/- 2.8 pg x 1(-1); week 7: 36.9 +/- 2.3 pg x 1(-1); P = 0.03]. Plasma 25(OH)D3 did not change significantly. Plasma PTH increased throughout the training break and retraining (week 0: 1.36 +/- 0.25 pmol x 1(-1); week 3: 2.02 +/- 0.43 pmol x 1(-1); week 5: 2.23 +/- 0.60 pmol x 1(-1); week 7: 2.63 +/- 0.34 pmol x 1(-1); P = 0.03). Albumin-corrected calcium values were transiently decreased during retraining (week 3: 2.77 +/- 0.08 mM; week 5: 2.47 +/- 0.05 mM; week 7: 2.66 +/- 0.07 mM; P = 0.01). Plasma CT did not change during training break, but was transiently decreased during retraining (week 0: 9.97 +/- 0.39 pmol x 1(-1); week 3: 9.91 +/- 0.37 pmol x 1(-1); week 5: 8.19 +/- 0.50 pmol x 1(-1); week 7: 9.02 +/- 0.45 pmol x 1(-1); P = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
This obituary describes the professional career of Robert J. Wherry, which spanned 48 years, from 1927 to 1975. Wherry was an exceptional example of a quantitative-industrial psychologist who was able to make independent, original academic contributions, and yet have an exceptional understanding of problems of application. Throughout his career, two of Wherry's overriding interests were in the development and application of statistical models for prediction and factor analysis. In addition to his contributions to the quantitative literature, Wherry made substantial contributions to industrial psychology, publishing extensively in the industrial literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
109.
In a cascaded plant with n sensing points, n independent feedback loops are available to achieve quantitative sensitivity specifications. The optimum design is defined as that which achieves this with minimum net effect, of the n sensor noise sources, at the plant input. A design procedure is presented wherein one works backwards step by step from the system output, designing each loop function Li almost as if the remaining loops (Li+j, j>0) are perfect. Even in large plant ignorance problems, only the outer loop Li may be large over some frequency range. In general |Li|max < 1, i ≠ 1 and |Li+1|max < |Li|max. Each Li has only one distinct frequency range say at ωc, i requiring trade-off between Li and Li+1. Only in this range is significant design effort required. However, ωc, i+1 >ωc, i so the primary price paid is in the steadily increasing “bandwidth” of each loop. The design procedure is highly transparent with strong universalistic features, permitting the use of universal design curves. 相似文献
110.
Compared the rate of learning-set formation by 4 rhesus monkeys that had previously been pretrained on the win-stay component of the learning-set strategy (Group WS) to the rate evidenced by 4 others that had pretraining on the lose-shift component (Group LS). Differences between groups were small, and asymptotic levels were below those previously obtained by monkeys without pretraining. The negative transfer resulted from generalized tendencies to perseverate or shift (Groups WS and LS, respectively), regardless of response outcome. The former tendency dissipated relatively rapidly, while the latter persisted very markedly throughout the 400-problem learning-set series. It is noted that learning-set formation requires a balance between the win-stay and lose-shift components; however, the optimal ratio is unknown. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献