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31.
Forty beef carcasses were classified for conformation and fatness. Besides, carcass weight, fat thickness (FT), carcass dimension, marbling by computer image analysis and ultrasound readings was recorded to complement grading. For predicting intramuscular fat (IMF) content, FT, number of intramuscular flecks and conformation increased R2-value from 0.19 to 0.64 compared to conformation alone. For visual marbling, ultrasound readings and thoracic depth (TD) increased the R2-value from 0.24 to 0.57 compared to fatness score (FS). The best variables for predicting weight of fabricated subprimals were carcass weight or compactness which is a function of carcass weight (R2 between 0.94 and 0.63). Fatness score was poorer than FT for predicting yield of subprimals cuts from round (R2 = 0.16 vs. 0.50) and ultrasound readings for less valuable subprimals (R2 = 0.31 vs. 0.39). These results showed that other variables could be used in combination with carcass fatness or conformation to achieve a more accurate estimation of fat and carcass yield. 相似文献
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Local instantaneous heat-transfer coefficients were measured for free convection from an isothermal cylinder vibrating sinusoidally in a horizontal plane. The results show that the heat-transfer coefficient is strongly dependent upon the ratio of amplitude of vibration to cylinder diameter, . For values of less than approximately 0·25, a critical vibration intensity was observed below which vibration caused only small increases in the heat-transfer rate; however, at greater than 0·25, the critical vibrational intensity did not appear to exist because the heat transfer from the cylinder increased as soon as the vibrational speed increased from zero. A correlation of the data is presented which predicts the increase in average heat transfer from the cylinder to air above the free convective rate.The correlation also applies to data for much larger vibrational intensities. 相似文献
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WN Roberts JP Brodeur J DeWitt SZ Carr CM Wise ME Carr 《Canadian Metallurgical Quarterly》1996,47(11):1081-1087
Electroimmunodiffusion (Laurell rocket) determinations of factor VIII-related antigen in plasma were ordered to determine the cost/benefit ratio for factor VIII-related antigen as a putative test for endothelial damage in suspected vasculitis. Twenty-seven consecutive patients referred for vasculitis or suspected vasculitis were identified and followed up for an average of 9.1 +/- months (range: one to thirty-three months) in a prospective, unblinded study performed in a clinic, associated with a 1054-bed inner-city university hospital. There was no difference in Westergren erythrocyte sedimentation rate (WESR) in patients with final diagnosis of systemic vasculitis (SV) (38 +/- 12 mm/hour) compared to those without vasculitis (NV) (27 +/- 7) as the final diagnosis. The mean plasma concentration of factor VIII-related antigen was significantly elevated in SV (344 +/- 100%) when compared with NV (147 +/- 39%) (P < 0.016). The factor VIII-related antigen test in this study was 2.56 times more likely (crude odds ratio) than the WESR to contribute to a change in diagnosis or therapy (P = 0.016). Positive and negative predictive values (PPV and NPV) for factor VIII-related antigen (abnormal at greater than 220% of the normal value) were both 70%. PPV and NPV for WESR were 56% and 86%, respectively. The factor VIII-related test was less cost-effective than the WESR in the follow-up period unless it was important to define complete remission or differentiate vasculitis flare from infection. The authors conclude that factor VIII-related antigen is a useful test in the initial diagnosis of vasculitis. 相似文献
36.
J Marszalek W Zhang TR Hupp C Margulies KM Carr S Cherry JM Kaguni 《Canadian Metallurgical Quarterly》1996,271(31):18535-18542
DnaA protein of Escherichia coli is a sequence-specific DNA-binding protein required for the initiation of DNA replication from the chromosomal origin, oriC. It is also required for replication of several plasmids including pSC101, F, P-1, and R6K. A collection of monoclonal antibodies to DnaA protein has been produced and the primary epitopes recognized by them have been determined. These antibodies have also been examined for the ability to inhibit activities of DNA binding, ATP binding, unwinding of oriC, and replication of both an oriC plasmid, and an M13 single-stranded DNA with a proposed hairpin structure containing a DnaA protein-binding site. Replication of the latter DNA is dependent on DnaA protein by a mechanism termed ABC priming. These studies suggest regions of DnaA protein involved in interaction with DnaB protein, and in unwinding of oriC, or low-affinity binding of ATP. 相似文献
37.
A. Chagnes H. Allouchi B. Carré G. Odou P. Willmann D. Lemordant 《Journal of Applied Electrochemistry》2003,33(7):589-595
-Butyrolactone-ethylene carbonate (BL-EC) mixtures have been investigated as electrolytes for Li-ion batteries using LiPF6 and LiBF4 as lithium salt. The thermal stability of the electrolytes in a large range of temperatures (–90 °C to 40 °C) have been studied by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). From the results of these experiments, the phase diagram of the BL-EC system has been determined. It is characterised by a eutectic point at –56.3 °C and a molar fraction in EC: x
EC = 0.1. A metastable compound has been demonstrated below –90 °C at x
EC = 0.4. Conductivity measurements of BL-EC solutions, in the presence of LiPF6 and LiBF4, indicate that LiPF6 in the eutectic mixture is the most conducting electrolyte in the range of temperatures investigated (–30 °C to room temperature). Nevertheless, at low temperature, LiBF4 based electrolytes compete well with LiPF6, especially when the amount of EC in the mixture is as high as x
EC = 0.5. Moreover, recrystallisation of the salt below –20 °C is avoided when LiBF4 is used as salt. A large increase in viscosity of the solvent mixture is observed when a salt is added, but the increase is lower for LiBF4 than LiPF6. When EC is added to BL at constant salt concentration (1 M), the conductivity of LiPF6 solutions decreases more rapidly than LiBF4 solutions. This has been attributed, at least partially, to the dissociating power of EC. The electrochemical windows of BL-EC (equimolar) mixtures in the presence of LiPF6 and LiBF4 are comparable but it is shown that the solvents oxidation rate at high potentials is lower when LiBF4 is used. 相似文献
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The chemical and conformational structures of Bombyx mori silk were studied with the complementary techniques of Fourier transform Raman spectroscopy and Fourier transform infrared spectroscopy. The Fourier transform Raman spectrum of silk showed strong bands for the photosensitive aromatic amino acids tyrosine, tryptophan, and phenylalanine. Intensive UV/ozone irradiation reduced the Raman intensities of the amide III band and the tyrosine signals due to peptide chain scission of the silk polymer and the photochemical changes in the tyrosine residues on the silk molecules. However, the Raman spectroscopy changes for tryptophan were less clearly defined because of peak overlapping with other amino acid signals and the low concentration of tryptophan. The Fourier transform infrared (attenuated total reflectance) technique, coupled with second‐derivative spectroscopy analysis, demonstrated a decrease in the crystallinity degree and tyrosine content of UV/ozone‐irradiated silk, as indicated by changes in the Fourier transform infrared bands of amide III doublet and tyrosine signals. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1999–2004, 2005 相似文献
40.
Chemical Composition and Physical Properties of High Oleic Safflower Oils (Carthamus tinctorius,Var. CW88-OL and CW99-OL) 下载免费PDF全文
Florencia Salaberría Diana Constenla Amalia A. Carelli María E. Carrín 《Journal of the American Oil Chemists' Society》2016,93(10):1383-1391
Chemical composition and physical properties of CW88‐OL and CW99‐OL cultivars of high oleic safflower seeds and their hexane‐extracted oils were determined. Dry‐based seed composition of CW88‐OL and CW99‐OL was: moisture = 4.29 and 4.23 %, oil = 42.29 and 46.44 %, Crude protein = 20.94 and 16.41 %, neutral detergent fiber = 28.11 and 28.49 %, ash = 1.55 and 2.01 %, phosphorus content = 2033 and 3995 mg/kg, respectively. Major fatty acids in oils were ~78 % oleic (O), ~13 % linoleic (L), ~5 % palmitic (P) and ~2 % stearic (St) acids, for both cultivars. The main triacylglycerols were OOO (~50 %), OOL (~20 %), SOL + OPO (~10 %), and LLP (~5 %). The oil composition of CW88‐OL and CW99‐OL in main minor components was: α‐tocopherol = 582 and 551 mg/kg, total sterols = 3996 and 3362 mg/kg, phospholipids = 22 and 21 mg/kg and wax content = 70 and 74 mg/kg. For both cultivars, density and viscosity of the oils between 25 and 55 °C varied from 903.4 to 912.6 kg/m3 and 63 to 23 mPa.s showing linear and exponential behaviors, respectively. The refractive index was 1.4694. The CIELab color parameters were: 89.69 and 89.53 (L*), ?3.72 and ?3.07 (a*), and 47.28 and 47.78 (b*) (CW88‐OL and CW99‐OL, respectively). Thus, the high oil content of the seeds and nutritional quality of the oil accompanied by low levels of waxes and phospholipids makes the cultivars studied promising for producers and consumers. 相似文献