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101.
Highly active perovskite‐based electrodes were obtained through partial substitution of lanthanides (La, Pr and Sm) by barium in the Ln0.58Sr0.4Fe0.8Co0.2O3 system. These compositions were obtained as single phase crystalline compounds through a sol–gel synthetic route and tested by electrochemical impedance spectroscopy (EIS) as symmetrical cells on GDC‐electrolyte samples in the temperature range 450–650 °C. Cooperative effects arose through the incorporation of a large divalent active cation (Ba+2) in the perovskite lattice of lanthanide‐based strontium ferrites‐cobaltites. Reduction in the electrode polarisation resistance with respect to non‐substituted compositions is obtained irrespective of the amount of barium substitution and lanthanide nature. Barium addition also reduces the activation energy of these compositions, indicating changes in the oxygen activation processes. The specific effect of the barium incorporation on the electrode performance was dependent on the nature of the partially substituted lanthanide. Lanthanum–barium‐based compositions exhibited the lowest electrode polarisation resistance when the amount of the replaced barium was increased up to 50% molar. On the other hand, for praseodymium‐ or samarium–barium‐based compositions, the minimum in electrode polarisation resistance was achieved at barium substitutions close to 25% molar. The study of the effect of oxygen partial pressure on EIS data allowed in improving the understanding of the processes governing the electrode operation. 相似文献
102.
Texture changes in dry-cured ham pieces by mild thermal treatments at the end of the drying process 总被引:2,自引:1,他引:1
The present study evaluated the effects of mild thermal treatments at the end of the drying process on physicochemical characteristics and instrumental and sensory texture in dry-cured ham. Experiment 1: effect of thermal treatments (4–46 °C) for 4 h and 24 h. Experiment 2: time effect (4–168 h) of thermal treatments at 30 °C and 36 °C. Both experiments were done on small dry-cured ham dices. Experiment 3: time effect (4–168 h) of thermal treatment at 30 °C on both instrumental and sensory texture of 4-cm-thick sections of dry-cured ham. The thermal treatment at 30 °C for 168 h on both dry-cured ham muscle dices (20 mm × 20 mm × 15 mm) and dry-cured ham sections (4 cm thick) decreased softness, adhesiveness and pastiness in BF muscle, without increasing hardness in SM muscle or affecting moisture, aw and proteolysis index. 相似文献
103.
Dr. Roser Borràs-Tudurí Dr. Anna Alcaide Dr. Sandrine Aspeslag Dr. Lorena Usero Dr. Carmen Serra Dr. Carme Roura-Mir Dr. Dirk Elewaut Dr. Amadeu Llebaria 《ChemMedChem》2021,16(16):2491-2496
Natural Killer T (NKT) cells play an important role in the immune response and can be activated by glycolipids presented by CD1d protein. We present MCS-0208, an unprecedented arylthioether-phytoceramide able to induce potent invariant NKT (iNKT) cell activation, notably when tested in human iNKT cells. This arylsphingolipid analog has a simple phenyl group containing a single hydroxyl substituent as a surrogate of the sugar ring. The phenylthioether structure contrasts with α-galactosylceramide ( 1 ), the prototypical glycolipid used to induce iNKT cell stimulation, where the galactose 2’-OH and 3’-OH substituents are accepted as the minimal footprint and considered critical for NKT T cell receptor (TCR) recognition. A computational study supports the recognition of aromatic compound by the CD1d and TCR proteins as radically new structures for NKT cell stimulation. 相似文献
104.
Marc Serra Colomer Birgitte Funch Natalia Solodovnikova Timothy John Hobley Jochen Förster 《Journal of the Institute of Brewing》2020,126(3):280-288
Several hop derived compounds in wort are known to be converted by yeast during fermentation, influencing the overall perception of the beer. A deeper understanding of such metabolic processes during fermentation is needed to achieve better control of the outcome. Here, the interaction between hop derived compounds and the yeast genera Brettanomyces was studied. Several Brettanomyces strains with different genomic backgrounds were selected, focusing on two traits: beta-glucosidase activity and nitrate assimilation. The role of three beta-glucosidases present in Brettanomyces bruxellensis and Brettanomyces anomalus and their impact on the final monoterpene alcohol profile was analysed. The beta-glucosidase activity was highly strain dependent, with B. anomalus CRL-49 exhibiting the highest conversion. Such activity could not be related to the release of aglycones from hops during fermentation, as a substantial part of such activity was intracellular. Nevertheless, the reduction of geraniol to β-citronellol was remarkably efficient for all Brettanomyces strains during fermentation, and it is suggested that two oxidoreductases BbHye2 and BbHye3 may have an influence. Moreover, the transfer of nitrate from hops to wort and its further assimilation by Brettanomyces species was analysed. The amount of nitrate in wort proved to be linearly proportional to the contact time of the hops with the wort. The level of nitrate assimilation by yeast was shown to be dependent on the nitrate assimilation cluster (YNR, YNI, YNT). Hence, the desired yeast strains may be selected according to the genetic make-up. © 2020 The Authors. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling 相似文献
105.
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107.
Francesco Traccis Valeria Serra Claudia Sagheddu Mauro Congiu Pierluigi Saba Gabriele Giua Paola Devoto Roberto Frau Joseph Francois Cheer Miriam Melis 《International journal of molecular sciences》2021,22(4)
Cannabis use among pregnant women is increasing worldwide along with permissive sociocultural attitudes toward it. Prenatal cannabis exposure (PCE), however, is associated with adverse outcome among offspring, ranging from reduced birth weight to child psychopathology. We have previously shown that male rat offspring prenatally exposed to Δ9-tetrahydrocannabinol (THC), a rat model of PCE, exhibit extensive molecular, cellular, and synaptic changes in dopamine neurons of the ventral tegmental area (VTA), resulting in a susceptible mesolimbic dopamine system associated with a psychotic-like endophenotype. This phenotype only reveals itself upon a single exposure to THC in males but not females. Here, we characterized the impact of PCE on female behaviors and mesolimbic dopamine system function by combining in vivo single-unit extracellular recordings in anesthetized animals and ex vivo patch clamp recordings, along with neurochemical and behavioral analyses. We find that PCE female offspring do not show any spontaneous or THC-induced behavioral disease-relevant phenotypes. The THC-induced increase in dopamine levels in nucleus accumbens was reduced in PCE female offspring, even when VTA dopamine activity in vivo and ex vivo did not differ compared to control. These findings indicate that PCE impacts mesolimbic dopamine function and its related behavioral domains in a sex-dependent manner and warrant further investigations to decipher the mechanisms determining this sex-related protective effect from intrauterine THC exposure. 相似文献
108.
V. Vasta M. Daghio A. Cappucci A. Buccioni A. Serra C. Viti M. Mele 《Journal of dairy science》2019,102(5):3781-3804
The interest of the scientific community in the effects of plant polyphenols on animal nutrition is increasing. These compounds, in fact, are ubiquitous in the plant kingdom, especially in some spontaneous plants exploited as feeding resources alternative to cultivated crops and in several agro-industry by-products. Polyphenols interact with rumen microbiota, affecting carbohydrate fermentation, protein degradation, and lipid metabolism. Some of these aspects have been largely reviewed, especially for tannins; however, less information is available about the direct effect of polyphenols on the composition of rumen microbiota. In the present paper, we review the most recent literature about the effect of plant polyphenols on rumen microbiota responsible for unsaturated fatty acid biohydrogenation, fiber digestion, and methane production, taking into consideration the advances in microbiota analysis achieved in the last 10 yr. Key aspects, such as sample collection, sample storage, DNA extraction, and the main phylogenetic markers used in the reconstruction of microbial community structure, are examined. Furthermore, a summary of the new high-throughput methods based on next generation sequencing is reviewed. Several effects can be associated with dietary polyphenols. Polyphenols are able to depress or modulate the biohydrogenation of unsaturated fatty acids by a perturbation of ruminal microbiota composition. In particular, condensed tannins have an inhibitory effect on biohydrogenation, whereas hydrolyzable tannins seem to have a modulatory effect on biohydrogenation. With regard to fiber digestion, data from literature are quite consistent about a general depressive effect of polyphenols on gram-positive fibrolytic bacteria and ciliate protozoa, resulting in a reduction of volatile fatty acid production (mostly acetate molar production). Methane production is also usually reduced when tannins are included in the diet of ruminants, probably as a consequence of the inhibition of fiber digestion. However, some evidence suggests that hydrolyzable tannins may reduce methane emission by directly interacting with rumen microbiota without affecting fiber digestion. 相似文献
109.
Pablo Hernndez‐Alonso Christopher Papandreou Mnica Bull Miguel Ruiz‐Canela Courtney Dennis Amy Deik Dong D. Wang Marta Guasch‐Ferr Edward Yu Estefanía Toledo Cristina Razquin Dolores Corella Ramon Estruch Emilio Ros Montserrat Fit Fernando Ars Miquel Fiol Lluís Serra‐Majem Liming Liang Clary B. Clish Miguel A Martínez‐Gonzlez Frank B Hu Jordi Salas‐Salvad 《Molecular nutrition & food research》2019,63(17)
110.
lvaro Hernez Albert Sanllorente Olga Castaer Miguel . Martínez‐Gonzlez Emilio Ros Xavier Pint Ramn Estruch Jordi Salas‐Salvad Dolores Corella ngel M. Alonso‐Gmez Lluis Serra‐Majem Miquel Fiol Jos Lapetra Enrique Gmez‐Gracia Rafael de la Torre Rosa‐María Lamuela‐Ravents Montserrat Fit 《Molecular nutrition & food research》2019,63(6)