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41.
Giuseppina Adiletta Loredana Liguori Donatella Albanese Paola Russo Marisa Di Matteo Alessio Crescitelli 《Food and Bioprocess Technology》2017,10(9):1631-1641
A preliminary characterization of two new soft-seeded pomegranate varieties (MR-100® and KINGDOM®) based on their main physico-chemical and nutritional parameters was reported. The two varieties showed significant differences (p ≤ 0.05) in polyphenols, anthocyanins and antioxidant activity. Kingdom pomegranate had higher polyphenols (2524.73 mg GAE/L), anthocyanins (752.49 mg C3gE/L) and antioxidant activity (EC50 13.58 μL/mL) than MR-100 (1792.74 mg GAE/L, 141.29 mg C3gE/L and EC50 47.53 μL/mL, respectively). Moreover, minimally processed arils of the two varieties were packaged in semipermeable and micro-perforated film at 5 °C, and the quality changes that occurred during storage condition (15 days) were investigated. During storage, Kingdom arils exhibited a better performance in terms of antioxidant activity, polyphenols and anthocyanin content with respect to MR-100. Furthermore, the packaging systems did not affect the estimated quality parameters for both varieties. Based on the sensory evaluation and microbial counts, both aril varieties reached, at 15-day storage, suitable values for commercial purpose. 相似文献
42.
Seyedeh Homa Fasihnia Seyed Hadi Peighambardoust Seyed Jamaleddin Peighambardoust Abdulrasoul Oromiehie Maral Soltanzadeh Donatella Peressini 《Journal of food science》2020,85(8):2317-2328
Polypropylene (PP) based active composite films were prepared by adding butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), and tertiary butylated hydroquinone (TBHQ) antioxidants using the extrusion molding process. All concentrations of BHT, 2% to 3% BHA, and 3% TBHQ significantly increased the tensile strength (TS) of the composite films compared with control films. Increasing antioxidant concentration decreased TS values for BHT films, whereas an opposite trend was observed for BHA and TBHQ films. BHA at < 2%, BHT at > 2%, and TBHQ at all added concentrations significantly reduced elongation at break (Eb) of the composite films compared to control films. Water vapor permeability (WVP) of 1% BHT film was not significantly different from control. However, other antioxidants especially at increased concentrations significantly increased WVP values. TBHQ films with 300% to 662% increase had the highest WVP and BHT films with 5% to 81% increase had the lowest WVP among composite films. All three antioxidants had a negative effect on the transparency of the films; however the effect of BHA at higher concentrations was greater. The antioxidants did not change the color attributes of the films. Films containing all antioxidants showed 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, which increased with increase in their concentration, especially for those containing 3 wt.% BHT and TBHQ. Overall, incorporating BHA and BHT into a PP matrix improved mechanical, barrier, antioxidant properties, and film appearance and consequently were proposed for the development of antioxidant active PP films. TBHQ film is not recommended for food packaging because of its weak mechanical properties (lower Eb and TS values, higher WVP, and greater migration). 相似文献
43.
Bruzda Grzegorz Polkowski Wojciech Polkowska Adelajda Nowak Rafał Kudyba Artur Książek Marzanna Lech Sebastian Karczewski Krzysztof Giuranno Donatella 《Journal of Materials Science》2022,57(28):13724-13735
Journal of Materials Science - Boron-doped molybdenum silicides have been already recognized as attractive candidates for space and ground ultra-high-temperature applications far beyond limits of... 相似文献
44.
Niccolò Renoldi Seyed Hadi Peighambardoust Donatella Peressini 《International Journal of Food Science & Technology》2021,56(7):3235-3244
In this work, corn extruded snack products were enriched with rice bran (RB) at 10% and 15%. A co-rotating twin-screw extruder was used with a feed moisture content of 16 g 100 g−1, a screw speed of 240 r.p.m. and four heating sections of the barrel (100, 140, 150 and 150 °C). The impact of RB inclusion on nutritional profile, starch digestion, physicochemical and textural properties of snack products was evaluated. RB-enriched extrudates showed a lower specific volume and hardness and higher crispness than control. RB at 15% gave a water-holding capacity lower than control. Rheology of extrudate dispersions indicated an increase in elastic interactions and solid-like behaviour with RB supplementation. Differences in rheological properties resulted in attenuation of predictive glycaemic response for RB-enriched snacks. 相似文献
45.
G Rocchitta O Secchi MD Alvau R Migheli G Calia G Bazzu D Farina MS Desole RD O'Neill PA Serra 《Analytical chemistry》2012,84(16):7072-7079
Ethanol is one of the most widespread psychotropic agents in western society. While its psychoactive effects are mainly associated with GABAergic and glutamatergic systems, the positive reinforcing properties of ethanol are related to activation of mesolimbic dopaminergic pathways resulting in a release of dopamine in the nucleus accumbens. Given these neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF) is of great importance. In this study, we describe the development and characterization of an implantable biosensor for the amperometric detection of brain ethanol in real time. Ten different designs were characterized in vitro in terms of Michaelis-Menten kinetics (V(MAX) and K(M)), sensitivity (linear region slope, limit of detection (LOD), and limit of quantification (LOQ)), and electroactive interference blocking. The same parameters were monitored in selected designs up to 28 days after fabrication in order to quantify their stability. Finally, the best performing biosensor design was selected for implantation in the nucleus accumbens and coupled with a previously developed telemetric device for the real-time monitoring of ethanol in freely moving, untethered rats. Ethanol was then administered systemically to animals, either alone or in combination with ranitidine (an alcohol dehydrogenase inhibitor) while the biosensor signal was continuously recorded. The implanted biosensor, integrated in the low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF and represents a new generation of analytical tools for studying ethanol toxicokinetics and the effect of drugs on brain ethanol levels. 相似文献
46.
A new approach to evaluating the toxicity and genotoxicity of disinfected drinking water 总被引:1,自引:0,他引:1
Monarca S Zani C Richardson SD Thruston AD Moretti M Feretti D Villarini M 《Water research》2004,38(17):3809-3819
The aim of this study was to evaluate the formation of toxic and genotoxic compounds in surface drinking waters treated with two widely used disinfectants, sodium hypochlorite (NaClO) and chlorine dioxide (ClO(2)), and a new disinfectant, peracetic acid (PAA). For this purpose a pilot plant was set up to add these biocides continuously to pre-filtered lake water flowing into three different basins. During three seasonal experiments, short-term in vivo tests (with plant, fish and molluscs) and in vitro tests (with bacteria, yeast and human cells) were carried out to evaluate the formation of genotoxic disinfection by-products (DBPs). Gas chromatography/mass spectrometry (GC/MS) was used to identify DBPs produced during the different treatments, microbiological analyses were performed to test the biocidal activity of the disinfectants, and chemical analyses were carried out to evaluate the quality of the water. The pilot drinking water plant under study was useful in studying the toxicity and genotoxicity of disinfected drinking water with this combined chemical/biotoxicological approach. This paper describes the setting up of the pilot plant and sets out/reports the results of the microbiological and chemical analyses. 相似文献
47.
48.
Lido Calorini Anna Fallani Donatella Tombaccini Emanuela Barletta Gabriele Mugnai Maria F. Di Renzo Paolo M. Comoglio Salvatore Ruggieri 《Lipids》1989,24(8):685-690
To determine whether a metastatic phenotype may be corelated with a characteristic lipid pattern, we compared the lipid composition
of low metastasizing Balb/c 3T3 cells transformed by the B77 strain of Rous sarcoma virus (B77-3T3 cells) with that of a subclone
isolated by growth in 0.6% agar, the B77-AA6 cells, which exhibit a high capacity for spontaneous metastasis. B77-3T3 cells
revealed characteristics in their lipid composition common to other systems of transformed cells, i.e., an accumulation of
ether-linked lipids, a reduction of the more complex gangliosides, an increase of oleic acid (18∶1) and a decrease of arachidonic
(20∶4) and C22 polyunsaturated fatty acids in phospholipids. High metastatic B77-AA6 cells showed: a) an even more marked
decrease of complex gangliosides; b) a more pronounced increase of 18∶1 and decrease of 20∶4 and 22 polyunsaturated fatty
acids in certain phospholipid classes; and c) a higher percentage of alkyl-acyl subfractions in both phosphatidylcholine and
phosphatidylethanolamine than B77-3T3 cells.
Comparing the data for other systems of metastatic cells with those of lipid studies of spontaneously metastasizing B77-AA6
cell system leads us to conclude that the metastatic phenotype is characterized by a change in ether-linked lipids, rather
than in fatty acids. 相似文献
49.
K. Bhanu Sankara Rao M. G. Castelli G. P. Allen John R. Ellis 《Metallurgical and Materials Transactions A》1997,28(2):347-361
The low-cycle fatigue (LCF) behavior of a wrought cobalt-base superalloy, Haynes 188, has been investigated over a range of
temperatures between 25 °C and 1000 °C employing a triangular waveform and a constant strain amplitude of ±0.4 pct. Correlations
between macroscopic cyclic deformation and fatigue life with the various microstructural phenomena were enabled through scanning
electron microscopy (SEM) and transmission electron microscopy (TEM), detailing the crack initiation and propagation modes,
deformation substructure, and carbide precipitation. Cyclic stress response varied as a complex function of temperature. Dynamic
strain aging (DSA) was found to occur over a wide temperature range between 300 °C and 750 °C. In the DSA domain, the alloy
exhibited marked cyclic hardening with a pronounced maximum at 650 °C. Dynamic strain aging has been documented through the
occurrence of serrated yielding, inverse temperature dependence of maximum cyclic stress, and cyclic inelastic strain developed
at half of the fatigue life. Additionally, the alloy also displayed a negative strain rate sensitivity of cyclic stress in
the DSA regime. These macroscopic features in the DSA domain were accompanied by the substructure comprised of coplanar distribution
of dislocations associated with the formation of pileups, stacking faults, and very high dislocation density. Toward the end
of the DSA domain, dislocation pinning by M23C6 precipitates occurred predominantly. The deformation behavior below and above the DSA domain has also been investigated in
detail. The temperature dependence of LCF life showed a maximum at ≈300 °C. The drastic reduction in life between 300 °C and
850 °C has been ascribed primarily to the deleterious effects of DSA on crack initiation and propagation, while the lower
life at temperatures less than 200 °C has been attributed to the combined influence of low ductility and larger cyclic response
stress. 相似文献
50.
Target Hopping as a Useful Tool for the Identification of Novel EphA2 Protein–Protein Antagonists 下载免费PDF全文
Dr. Daniele Pala Dr. Simonetta Russo Dr. Riccardo Castelli Dr. Iftiin Hassan‐Mohamed Dr. Carmine Giorgio Dr. Alessio Lodola 《ChemMedChem》2014,9(1):67-72
Lithocholic acid (LCA), a physiological ligand for the nuclear receptor FXR and the G‐protein‐coupled receptor TGR5, has been recently described as an antagonist of the EphA2 receptor, a key member of the ephrin signalling system involved in tumour growth. Given the ability of LCA to recognize FXR, TGR5, and EphA2 receptors, we hypothesized that the structural requirements for a small molecule to bind each of these receptors might be similar. We therefore selected a set of commercially available FXR or TGR5 ligands and tested them for their ability to inhibit EphA2 by targeting the EphA2‐ephrin‐A1 interface. Among the selected compounds, the stilbene carboxylic acid GW4064 was identified as an effective antagonist of EphA2, being able to block EphA2 activation in prostate carcinoma cells, in the micromolar range. This finding proposes the “target hopping” approach as a new effective strategy to discover new protein–protein interaction inhibitors. 相似文献