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481.
482.
Demerdash N.A.O. Gallagher R.H. Schilling R.J. Svoboda J.A. 《Education, IEEE Transactions on》1993,36(1):94-102
The impact of academic computing on undergraduate electrical engineering courses at Clarkson University is described. The many changes made possible or made necessary by the ready availability of the computer are organized in two broad categories: changes to content and changes in presentation. Changes to content are appropriate since techniques that would require prohibitive effort if done by hand have now become manageable with the computer as a tool. Changes in presentation are also appropriate because computing power can be used to present material in ways that foster insight 相似文献
483.
484.
This paper presents a study on the stability of dispersions of multiwalled carbon nanotubes that are covered with α-pyrene functionalized polymers prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization and dispersed in different solvents. We find that a rather small amount of these polymers (Mpolymer/MCNT less than 0.1) is capable of stabilizing a high concentration of CNTs (up to 2500 mg/l) in solution. Another strong evidence for well-stabilized CNTs is the comparably low gel points of around 1 vol% of CNTs in solution. We find that adding the α-pyrene functionalized polymer to CNTs has two counter playing effects: on the one hand, increased surface coverage of the carbon nanotubes increases their solubility; on the other hand increased concentration of free polymer in the solution enhances the depletion forces between the nanotubes. 相似文献
485.
Corinna Schilling Thomas Mack Selene Lickfett Stefanie Sieste Francesco S. Ruggeri Tomas Sneideris Arghya Dutta Tristan Bereau Ramin Naraghi Daniela Sinske Tuomas P. J. Knowles Christopher V. Synatschke Tanja Weil Bernd Knll 《Advanced functional materials》2019,29(24)
There is an urgent need for biomaterials that support tissue healing, particularly neuronal regeneration. In a medium throughput screen novel self‐assembling peptide (SAP) sequences that form fibrils and stimulated nerve fiber growth of peripheral nervous system (PNS)‐derived neurons are identified. Based on the peptide sequences and fibril morphologies and by applying rational data‐mining, important structural parameters stimulating neuronal activity are elucidated. Three SAPs (SAP1e, SAP2e, and SAP5c) enhance adhesion and growth of PNS neurons. These SAPs form 2D and 3D matrices that serve as bioactive scaffolds stimulating cell adhesion and growth. The newly discovered SAPs also support the growth of CNS neurons and glia cells. Subsequently, the potential of SAPs to enhance PNS regeneration in vivo is analyzed. For this, the facial nerve driving whisker movement in mice is injured. Notably, SAPs persist for up to 3 weeks in the injury site indicating highly adhesive properties and stability. After SAP administration, more motor neurons incorporating markers for successive regeneration are observed. Recovery of whisker movement is elevated in SAP‐injected mice. In summary, short peptides that form fibrils are identified and the adhesion, growth, and regeneration of neurons have been efficiently enhanced without the necessity to attach hormones or growth factors. 相似文献
486.
Floodplains exert important controls on water and nutrient processing, yet spatial heterogeneities in floodplain characteristics result in variable effectiveness. In this study, we evaluated the spatial relations among topographic, lithologic and water quality features within the Cedar River floodplain located in southeastern Iowa. Floodplain topography and lithology were dominated by a series of sandy ridges and fine‐textured swales typical of a natural meandering river floodplain complex. Groundwater sampling results from 10 monitoring wells placed in representative ridge and swale environments indicated that water quality varied systematically. Beneath sand‐dominated ridges, water was aerobic and had low specific conductance, and higher concentration of NO3–N and lower concentrations of PO4–P and dissolved organic carbon (DOC). Groundwater beneath swales was anaerobic and typified by high specific conductance, and higher concentrations of NH4–N, PO4–P and DOC. We extrapolated the results from point measurements to the entire floodplain area using surface geophysics and light detection and ranging using co‐kriging to map the distribution of groundwater geochemical environments at the study site. Results are seen to provide an approach to better predict shallow groundwater quality in large river floodplains and improve our ability to manage ecosystem services in these strategic locations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
487.
In this paper we consider the problem of reconstructing triangular surfaces from given contours. An algorithm solving this problem must decide which contours of two successive slices should be connected by the surface (branching problem) and, given that, which vertices of the assigned contours should be connected for the triangular mesh (correspondence problem). We present a new approach that solves both tasks in an elegant way. The main idea is to employ discrete distance fields enhanced with correspondence information. This allows us not only to connect vertices from successive slices in a reasonable way but also to solve the branching problem by creating intermediate contours where adjacent contours differ too much. Last but not least we show how the 2D distance fields used in the reconstruction step can be converted to a 3D distance field that can be advantageously exploited for distance calculations during a subsequent simplification step. 相似文献
488.
S. Kin M.W. Schilling B.S. Smith J.L. Silva V. Jackson T.J. Kim 《Journal of food science》2010,75(1):S74-S80
ABSTRACT: Catfish fillets were injected to 115% over green weight prior to tray-packing and storage at 4 °C for 1, 4, 8, and 11 d. Fillets were evaluated for yields, surface color, pH, cooking loss, tenderness, purge loss, and shelf-life. All phosphate treatments increased ( P < 0.05) fillet tenderness, but the agglomerated blend of sodium phosphates (AGSP) increased ( P < 0.05) pH and yields, and decreased ( P < 0.05) CIE L * and CIE b * values. Psychrotrophic plate counts (PPC) of fillets treated with the agglomerated blend of polyphosphates (AGPP) were lower ( P < 0.05) than the control at each storage time, but PPC of all samples reached 7 log CFU/g by day 8 of storage. All agglomerated phosphates and STP (sodium tripolyphosphate) improved yields and quality when compared to the nonmarinated control. However, AGSP was the most effective phosphate at increasing pick-up and yields and decreasing cooking loss due to the pH effect that causes more water to be trapped within the food system. Major quality differences may not have occurred between STP and agglomerated phosphates (other than AGSP) since injection relies solely on pH and ionic strength for marinade pickup, whereas tumbling also relies on mechanical action, which relies more on the presence of various phosphate chain lengths and solubility to impact yields. All phosphate treatments improved the quality of tray-packed, refrigerated catfish fillets that were enhanced through multineedle injection. However, AGSP also increased fillet pH, optimized yields, and improved color.
Practical Application: Use of an agglomerated phosphate blend with a high pH (AGSP) maximized the yield of catfish fillets that were marinated through multineedle injection. In addition, STP and agglomerated phosphate blends increased the yield and tenderness of catfish fillets when compared to the nonmarinated control. 相似文献
Practical Application: Use of an agglomerated phosphate blend with a high pH (AGSP) maximized the yield of catfish fillets that were marinated through multineedle injection. In addition, STP and agglomerated phosphate blends increased the yield and tenderness of catfish fillets when compared to the nonmarinated control. 相似文献
489.
R.K. Sekhon M.W. Schilling T.W. Phillips R.M.J. Aikins M.M. Hasan R. Nannapaneni W.B. Mikel 《Journal of food science》2010,75(5):C452-C458
Abstract: Randomized complete block designs with 3 replications were utilized to evaluate the effects of carbon dioxide (CO2) (0% at 96 h, 60% at 48 h, and 60% at 96 h) and ozone (O3) (0 and 175 ppm for 48 h) on the volatile flavor compound concentrations in dry-cured ham. Minimal differences existed in the presence and concentration of aroma active compounds in both CO2 and O3 fumigated hams but phenols were slightly more prevalent (P < 0.05) in the CO2 treatments and oxidation compounds were slightly elevated (P < 0.05) in the ozone treated samples when compared to the control. Triangle tests (n = 54 and 56) indicated that consumers could not discern (P > 0.75) between the control hams and the hams that were fumigated with CO2 and O3, respectively. This study revealed that there were minimal aroma/flavor differences among the ham treatments between 0 and 60% CO2 for 96 h; and also between 0 and 175 ppm O3. 相似文献
490.
The antimicrobial activity of various essential oils and carvacrol was determined on fresh raw catfish fillets against a 4-strain Listeria monocytogenes mixture representing serotypes 1/2b, 3b, 4b, and 4c that were predominantly isolated from catfish processing environments. Thyme oil, oregano oil and carvacrol exhibited concentration and time dependent responses in broth against L. monocytogenes; for example 0.5% concentrations resulted in 4 log CFU/mL reduction within 30 min whereas 0.1% concentrations required more than 24 h for the same level of reduction. Lemon, orange, and tangerine oils, at 0.5% showed listeriostatic effect in which 4 log CFU/mL of the initial L. monocytogenes load was unchanged at 4 °C in 10 d whereas 1% concentrations were listericidal in a time dependent manner. Apart from carvacrol, efficacy of tested essential oils in reducing L. monocytogenes and total microbial load from catfish fillet was very limited. Dipping treatment of catfish fillets in 2% carvacrol solution for 30 min at 4 °C reduced L. monocytogenes to an undetectable level from their initial load of 5 log CFU/g and reduced total microbial load from catfish fillets by approximately 5 log CFU/g. In sensory analysis trained panelist preferred control samples over 2% carvacrol treated samples implying potential limitation in applicability of carvacrol for fillet treatments. 相似文献