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51.
Three concentrations of oat flour (OF), 0, 2 and 4% (w/w), were added to beef patties which had either 5, 10 or 20% fat levels. Raw and cooked patties were analysed for protein, fat, moisture, ash and pH. Patties were further evaluated for cooking characteristics, colour parameters (L*, a*, b*) and sensory properties. Moisture content decreased in raw patties as a result of the addition of OF but OF increased the moisture content of cooked patties. OF addition did not change the protein, fat and ash contents of either raw or cooked patties. Increasing fat concentration decreased cooking yield. OF improved the cooking characteristics of patties. Reducing the fat significantly decreased the lightness values of patties. Patties with OF had slightly higher b* values than control treatments. Increasing fat level increased juiciness, flavour and texture scores and 4% OF increased the juiciness scores, OF had no effect on other sensory properties.  相似文献   
52.
The purpose of the this article is to describe an emerging neuroimaging technology, functional near-infrared spectroscopy (fNIRs), which has several attributes that make it possible to conduct neuroimaging studies of the cortex in clinical offices and under more realistic, ecologically valid parameters. fNIRs use near-infrared light to measure changes in the concentration of oxygenated and deoxygenated hemoglobin in the cortex. Although fNIR imaging is limited to the outer cortex, it provides neuroimaging that is safe, portable, and very affordable relative to other neuroimaging technologies. It is also relatively robust to movement artifacts and can readily be integrated with other technologies such as EEG.  相似文献   
53.
The biosorption of lead(II), cadmium(II) and nickel(II) ions from aqueous solution by Spirulina platensis was studied as a function of time, concentration, temperature, repetitive reactivity, and ionic competition. The kinetic results obeyed well the pseudo second-order model. Freundlich, Dubinin Radushkevich and Temkin isotherm models were applied in describing the equilibrium partition of the ions. Freundlich isotherm was applied to describe the design of a single-stage batch sorption system. According to the thermodynamic parameters such as DeltaG degrees, DeltaH degrees and DeltaS degrees calculated, the sorption process was endothermic and largely driven towards the products. Sorption activities in a three metal ion system were studied which indicated that there is a relative selectivity of the biosorbent towards Pb2+ ions. The measurements of the repetitive reusability of S. platensis indicated a large capacity towards the three metal ions.  相似文献   
54.
Degradation of Congo Red (CR) dye in aqueous solutions was investigated by means of photocatalysis of TiO2 which was hydrothermally synthesized at 200 degrees C in 2 h, in anatase phase with 8 nm crystallite size. Efficiency of TiO2 in photocatalytic degradation under visible irradiation was studied by investigating the effects of amount of TiO2, irradiation time, initial CR concentration and pH. It was found that complete decolorization is achieved within 30 min of irradiation. Effects of nitrate and sulphate ions and humic acid on the degradation were also tested. The results were compared with Degussa P-25 TiO2 at the same degradation conditions. Degradation products were detected using LC-MS technique. The probable pathways for the formation of degradation products were proposed.  相似文献   
55.
The preparation of poly(5-nitroindole) (P5NI) coating was achieved on 316L-stainless steel (SS). Poly(5-nitroindole) was deposited via anodic oxidation of the corresponding monomer in acetonitrile (ACN) solution containing LiClO4. The influence of P5NI coating against SS corrosion was studied in 3.5% NaCl solution by electrochemical impedance spectroscopy (EIS), anodic polarization curves and the open circuit potential–time (Eocpt) diagrams. The results obtained suggest that P5NI coating forms a sacrificial layer but the efficiency against corrosion is limited with increasing time.  相似文献   
56.
Biofilm formation by 30 Staphylococcus aureus dairy isolates and their control by phytochemicals were investigated. The majority of strains were biofilm positive by phenotypic analysis. The nuc and icaA genes were present in 30 and 27 strains, respectively. In addition, 13 strains were positive for all nuc, clfA, fnbA and icaA genes. The antimicrobial and antibiofilm activities of citral, cinnamaldehyde, eugenol, farnesol, limonene and terpinen‐4‐ol were also evaluated for seven strains. It was shown that the use of farnesol, cinnamaldehyde or terpinen‐4‐ol at a concentration of 2 mg/mL could be at least 80% effective on S. aureus strains and their biofilms.  相似文献   
57.
The drying mechanism of fermented sausages (sucuks) that were cylindrical rod shaped, 40 cm long and 4 cm diameter, during ripening under natural convection conditions at different temperatures (15 to 30°C) was examined. To simulate the experimental drying curves, three empirical models and a diffusional model assuming negligible external mass transfer resistance were evaluated. The drying rate curves of sucuk samples were also simulated taking into account the influence of the external mass transfer resistance. The equation was solved using the trial-and-error solution algorithm developed in this study and the mass transfer coefficient, k c , and effective moisture diffusivity, D eff , were simultaneously determined (1.44 × 10?8 to 1.93 × 10?8 m/s and 4.30 × 10?10 to 6.85 × 10?10 m2/s, respectively). The proposed model considering the effect of external resistance allowed the accurate simulation of the experimental drying data of sucuks at different temperatures.  相似文献   
58.
We present a simple strategy to prepare doxorubicin (DOX) containing hydrogen‐bonded films of poly(2‐isopropyl‐2‐oxazoline) (PIPOX) and tannic acid (TA) which release DOX in acidic conditions while releasing a minimal amount of DOX at physiological pH. Water soluble complexes of TA and DOX (TA ? DOX) were prepared prior to film construction. PIPOX and TA ? DOX were deposited at the surface at pH 6.5 using the layer‐by‐layer (LbL) technique. We found that multilayers released a minimal amount of DOX at physiological pH due to further ionization of TA with increasing pH and enhanced electrostatic interactions between TA and DOX. In contrast, pH‐induced release of DOX was observed in moderately acidic conditions due to protonation of TA as the acidity increased and electrostatic interactions between TA and DOX decreased. Moreover, we found that raising the temperature from 25 °C to 37.5 °C increased the amount of DOX released from the surface. This can be rationalized with the conformational changes within the multilayers correlated with the lower critical solution temperature behaviour of PIPOX and increased kinetic energy of DOX molecules. Considering the acidic nature of tumour tissues and important biological properties of PIPOX and TA, these multilayers are promising for pH‐ and temperature‐triggered release of DOX from surfaces. © 2017 Society of Chemical Industry  相似文献   
59.

Conductive polymers with good conductivity and large surface area are used as N-precursor materials for N-doped carbon-based catalysts and increase the catalytic activity of the electrode. Therefore, synthesis of the novel highly conductive polymer is an essential issue. This study reports that the synthesis of a novel copolymer is called poly(indole-4-aminoquinaldine) successfully achieved both chemically and electrochemically. The effect of scan rate, scan number, monomer concentration, and solvent on the polymerization process was investigated, and hereby the optimum synthesis conditions for the copolymer were determined. Under optimum conditions, the polyindole was also synthesized electrochemically and properties of polyindole compared to poly(indole-4-aminoquinaldine). The electrochemical characterization was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrical conductivity of the poly(indole-4-aminoquinaldine) and polyindole was measured using a four-point probe technique as 6 S/cm and 1?×?10–2 S/cm, respectively. Additionally, bandgap of copolymer and polyindole was found to be 3.10 and 3.18 eV, respectively. The structural, thermal, and morphological analysis of poly(indole-4-aminoquinaldine) and polyindole were carried out with UV–Vis Spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), elemental mapping, scan electron microscopy (SEM), and energy-dispersive X-ray analyzer (EDX) techniques. The novel copolymer synthesized in this study has high thermal stability and high electrochemical activity as well as high conductivity.

  相似文献   
60.
Catalytic operations, achieving considerable energy savings, continue getting wider application especially in clean energy systems. Perovskite materials, owing to their chemical and thermal stability, can be conveniently used as catalysts and electrode materials at wide temperature ranges. Hydrogen sulfide (H2S) offers a new and abundant source of hydrogen, the ultimate energy carrier. In the present work, change in electrical conductivity of catalysts obtained by adding molybdenum (Mo) and vanadium (V) as B to the perovskite structure with lanthanum (La) and strontium (Sr) as A and A′, respectively, has been studied within a temperature range of up to 1100 K. Samples La0.75Sr0.25MoO3 and LaSr0.5V0.5O3 demonstrated the highest values of conductivity at 1100 K. At lower temperatures, Cr-added Mo and V catalysts La0.9Sr0.1Cr0.5Mo0.5O3 and La0.9Sr0.1Cr0.5V0.5O3 had higher conductivity, closely followed by LaSr0.5V0.5O3.  相似文献   
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