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61.
Theo van Kempen Bill Park Mike Hannon Paul Matzat 《Journal of the science of food and agriculture》2001,81(8):726-730
The ability to mix a quality feed is often equated to the quality of the mixer; the ability to weigh ingredients correctly has received little attention. To assess how accurately feed mills weigh their ingredients, 14 feed mills specialising in swine diets were surveyed, which yielded 8432 data points (for 229 ingredients and 11–44 batch records per ingredient within mills). Amounts actually weighed (according to scale readings) were compared to calls, and differences were analysed statistically. Feed mills overdosed ingredients by 1.5 ± 16.3%: between mills, overdosing ranged from ?0.7 to 13.0%. Within ingredients, weighing variation ranged from 0.6 to 11.1% between mills and averaged 5.2%. Some of the weighing problems observed were attributed to discrepancies between the call size and the scale resolution. For example, weighing 11.3 units (pounds) on a scale with a 2 unit resolution leads to a minimum error of 6%. Such problems occurred for 8.7% of the calls and resulted in a minimum error ranging from 0.01 to 20%, averaging 1.95%. Poor choice of scales was the major source of errors in weighing, and the relationship weighing variation = 10∧ [1.56 ? 0.50 log (call/scale resolution)] explained 40% of the variation observed (p < 0.05). Weighing ingredients in the right scale would thus not only benefit feed quality but also reduce diet cost, as it would reduce the overdosing of ingredients. © 2001 Society of Chemical Industry 相似文献
62.
Meckelein Barbara; Nikiforov Theo; Clemen Annette; Appelhans Heribert 《Protein engineering, design & selection : PEDS》1990,3(3):215-220
Human mucus proteinase inhibitor (MPI) consists of 107 aminoacids arranged in two domains showing high homology to eachother. This protein is an inhibitor of different serine proteinasesincluding trypsin, chymotrypsin, leukocyte elastase and cathepsinG. On the basis of sequence comparisons it has been suggestedthat the first domain inhibits trypsin, whereas the second onewas thought to be active against chymotrypsin and elastase.To prove the location of the different inhibitory activitiesgene fragments for both domains have been cloned separatelyand expressed in Escherichia coli. Inhibition assays with theisolated recombinant domains showed that the second domain isactive against chymotrypsin, neutrophil elastase and trypsin,whereas for the first domain only a weak activity against trypsincould be detected. These results suggest that the inhibitoryactivities of the native molecule towards these three proteinasesare all located in the second domain. 相似文献
63.
Potvin Alfred R. Crosier William G. Fromm Eli Lin James C. Neuman Michael R. Pilkington Theo C. Robinson Charles J. Schneider Lawrence W. Strohbehn John W. Szolovits Peter Tompkins Willis J. 《IEEE transactions on bio-medical engineering》1986,(1):48-59
MORE than 200 years ago, our forefathers made note of man's inalienable rights to life, liberty, and the pursuit of happiness. To the engineering community (applied science in the service of man), these may be coincident with applications to medicine and biology (biomedical engineering), defense, and entertainment. Biomedical engineering research has the distinction, among these three missions, of not only contributing to the quality of human life through the industrial economy but also to life itself?the most fundamental concern of all people. It is through biomedical engineering research that we have been able to learn much concerning the functioning of living systems, and it is through such knowledge that we have been able to develop improved clinical diagnosis, monitoring, and treatment, including life-sustaining devices and aids to the handicapped. Each step represents an improvement in the quality of life, and each step forms the foundation upon which to gain new knowledge to improve upon earlier developments. 相似文献
64.
65.
Gerard E. O’Connor Jeffrey Evans Scott Black Neil Fettell Beverley Orchard Ron Theo 《Nutrient Cycling in Agroecosystems》2010,86(2):269-286
Nitrate is known to accumulate under legume crops. The effects of legume crop, inoculation, row width, sowing rate, sowing
date, and intra-cropping with wheat, on the amount and soil distribution of mineral N, residual soil water, crop biomass and
crop N were studied at Wagga Wagga in south-east Australia. After removal of most of the above-ground plant material, the
treatment effects on the biomass, N content, grain yield and grain N of wheat, established in the following season, were also
measured. In a later experiment at Wagga, the recovery of 15N applied to the mid-row of lupin crops established at three row
widths was estimated at crop maturity. At Condobolin, row width effects on the soil distribution of mineral N, biomass, N
accumulation and N fixation of crop legumes and cereals, were determined. At physiological maturity, at Wagga Wagga, very
little nitrate was left beneath cereals. Significantly more was left under legume crops, mostly below 30 cm of soil depth,
and it was distributed differently depending on crop, inoculation, and sampling location. More nitrate was left under pea
and faba than under lupin, and in response to inoculation. Mixing wheat with narrow-leaf lupin did not prevent nitrate accumulation
in soil. For most of the legumes more nitrate was left in the mid-row than in the in-row; and more nitrate was left at the
mid-row of lupin crops sown with wider rows. The additional nitrate left with wider rows increased the growth, N content,
grain yield and protein of wheat established in the following season. 15N labelled nitrate applied mid-row was used less effectively
by lupin as row width increased, in a dry season. At Condobolin, lupin established with wide rows used less soil nitrate than
with narrower rows but maintained crop N by increased N fixation. In contrast, field pea maintained N demand by increasing
nitrate uptake at intermediate row spacing. The study shows that the amount of nitrate accumulated in soil during legume cropping
is susceptible to agronomic management, particularly crop selection, row width and inoculation; and that variation in the
amount of this nitrate may carry forward to impact wheat production in the follow-on season. 相似文献
66.
The T-stress term of DCDC specimens is computed using the Boundary Collocation procedure and limit case consideratons. This parameter allows to understand path stability as found in literature for subcritical crack growth in galss. 相似文献
67.
68.
This study evaluated the design of step-gradient, single-pulse, multi-pulse, and continuous injection of biodegradable EDDS ([S,S]-ethylene-diamine-disuccinic acid, under the same total dosage) and the significance of pore-water velocities during in situ soil flushing. In view of the metal breakthrough and extraction efficiency of each injection mode, single-pulse injection was found to be the least effective for all metals. Multi-pulse injection was consistently more effective than single-pulse injection, although the efficiency of second and third pulse injections significantly diminished. Continuous injection offered a simple operation and the greatest Ni and Cu extraction, whereas step-gradient injection was the best option for Zn and Pb extraction because it mitigated the influence of metal exchange. Moreover, a rinsing step with a background solution following the initial injection of the multi-pulse injection removed newly formed metal-EDDS complexes from soil pores effectively before further EDDS-flushing. A decrease in pore-water velocity provided a longer residence time for greater Ni and Cu extraction, but also enhanced the rate-limited metal exchange of Zn-EDDS and Pb-EDDS complexes and thus hindered Zn and Pb extraction. These results suggest a slower and continuous injection for the best Ni or Cu removal, but a faster and step-gradient injection for Zn or Pb removal. 相似文献
69.
Pavan TZ Almeida TW Carneiro AA 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(5):909-915
The dynamic behavior of a rigid magnetic sphere induced by an acoustic radiation force was investigated. The sphere was suspended in water in a simple pendulum configuration. The drag force acting on the pendulum during its motion was considered to follow a modified Stokes law for a low Reynolds number, accounting for phenomena related to its oscillatory movement. Steady forces of long (a few seconds) and short (a few milliseconds) durations were used. The movement of the magnetic sphere was tracked using a magnetoresistive sensor. From the new equilibrium position of the sphere in response to the long-duration static radiation force, the amplitude of this force was estimated. To assess the water viscosity, the relaxation movement after the acoustic force had stopped was fitted to a harmonic-motion model. Based on the results for the acoustic force and water viscosity, a theoretical profile of the sphere's micro-order displacement as a function of time caused by short-duration acoustic radiation force agreed well with experimental results. 相似文献
70.
Theo Pilhofer 《化学,工程师,技术》1984,56(4):299-305
Scope of glass as material of construction in plant engineering. In conjunction with PTFE as sealing material, borosilicate glass is nowadays recognized as a material for plant construction. A complete modular system of individual components with suitable connecting pieces is available. Moreover, a variety of equipment has been developed for accomplishing various processes while paying due attention to the special material properties of the material glass. In combination with other materials, primarily in the field of heat exchangers and evaporators, numerous processes are now conducted without any difficulty in glass plant. In this range of processes, a special place is assumed by those which urgently require glass for corrosion reasons, such as chlorination or bromination reactions or concentration of acids, because specialized know-how is sometimes required. 相似文献