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61.
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Pfannkuchen M Godrijan J Pfannkuchen DM Iveša L Kružić P Ciminiello P Dell'Aversano C Dello Iacovo E Fattorusso E Forino M Tartaglione L Godrijan M 《Environmental science & technology》2012,46(10):5574-5582
Mass appearances of the toxic dinoflagellate genus Ostreopsis are known to cause dangerous respiratory symptoms in humans exposed to aerosols. The outbreaks can appear in shallow marine waters of temperate regions around the globe. We followed a massive bloom event on a public beach on the northern Adriatic coast near Rovinj, Croatia. We identified the responsible species and the produced toxins as well as the dynamics of the event with respect to environmental conditions. Ostreopsis cf. ovata appeared in masses from September through October 2010 on a public beach near Rovinj, Croatia but stayed undetected by public health organizations. Respiratory symptoms were observed whenever humans were exposed to substrate samples containing large numbers of Ostreopsis cells. During the mass abundance of O. cf. ovata also exposure to the aerosols on the beach evoked respiratory symptoms in humans. Our measurements showed high cell abundances and high toxin contents with a stable relative contribution of putative Palytoxin and Ovatoxins a-e. Artificial beach structures proved to dramatically reduce settling of the observed Ostreopsis biofilm. Blooms like those reported herein have a high potential to happen undetected with a high potential of affecting the health of coastal human populations. Increased monitoring efforts are therefore required to understand the ecology and toxicology of those bloom events and reduce their negative impact on coastal populations. 相似文献
63.
Petruzzi L Bevilacqua A Ciccarone C Gambacorta G Irlante G Lamacchia C Sinigaglia M 《Journal of the science of food and agriculture》2012,92(2):343-350
BACKGROUND: Two red wines (Primitivo and Uva di Troia) treated with oak chips inoculated with Penicillium purpurogenum were analysed in order to assess their contents of furfural, cis‐β‐methyl‐γ‐octalactone, syringol, eugenol, vanillin and 4‐vinylguaiacol. Two different sizes of oak chips (small and big, of length 2 and 8 mm respectively) and two different degrees of toasting (low and high) were used in the study. Aroma compounds were analysed by gas chromatography/mass spectrometry to determine differences among samples after 15 days of chip contact time. RESULTS: Big oak chips inoculated with P. purpurogenum increased the level of 4‐vinylguaiacol, while small oak chips inoculated with P. purpurogenum, in some conditions, increased the level of eugenol. Chip size and degree of toasting also played an important role in the content of eugenol. CONCLUSION: The use of oak chips inoculated with mould might be a promising alternative to barrel aging. Moreover, different fungal inocula could contribute to the enrichment of wine with specific compounds (e.g. 4‐vinylguaiacol and eugenol). Copyright © 2011 Society of Chemical Industry 相似文献
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Four experiments examined whether scene processing is facilitated by layout representation, including layout that was not perceived but could be predicted based on a previous partial view (boundary extension). In a priming paradigm (after Sanocki, 2003), participants judged objects' distances in photographs. In Experiment 1, full scenes (target), partial scenes, and two control primes were used. Partial scenes excluded the target objects' locations, but these areas could be predicted. Full and partial scenes produced equal performance facilitation. In Experiment 2, task-irrelevant partial scene primes were also tested. These primes did not facilitate performance (i.e. simple scene previews did not help). Experiment 3 showed that a partial prime's utility depended on the area of the scene that would be tested; the task-irrelevant primes used in Experiment 2 were useful for other distance judgments. Experiment 4 showed that partial scene facilitation is not limited to the area immediately surrounding the prime. The study demonstrated that perceived and mentally extrapolated layouts are equally effective. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
66.
De Santo NG De Santo RM Perna AF Bisaccia C Pišot R Cirillo M 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(2):178-182
Nowadays, there is a renewed interest in bone changes in experimental and clinical nephrology. However, the need for understanding the peculiarity of bone can be traced back to the 5th century BC, when Empedocles of Acragas put forward a theory of a world made of air, water, fire, and earth governed by love and hate. By observing the various body tissues, he strove to demonstrate that they consisted of 4 elements assembled with different mathematical ratios (logos). Blood is considered the most perfect tissue, because the ratio between elements is one. Bone is a very unusual tissue because it is made of 2 parts of earth, 2 parts of water, and 4 parts of fire. This kind of reasoning could be considered the first cry in the birth of quantitative chemistry. 相似文献
67.
E. PiperopoulosS. Santangelo M. LanzaG. Faggio G. MessinaS. Galvagno A. PistoneC. Milone 《Diamond and Related Materials》2011,20(4):532-537
Nanotubes-based nanocomposites to be used as polymer reinforcing/flame-retardant additives are synthesized by decomposition of isobutane at 600 °C. Catalytic chemical vapor deposition (CCVD) is carried out over 17 wt%Fe-catalysts supported on various oxides (Al2O3, MgO, CaO, SrO or BaO) reduced at 600 °C. Catalysts utilized and carbonaceous deposits obtained are systematically characterized by the use of several analysis techniques, in order to investigate the influence of catalyst specifics on reaction yield, selectivity and characteristics (crystallinity and purity) of the grown nanotubes. The results show that the support greatly influences the catalyst performance. The lack of metallic iron renders Fe/SrO- and Fe/BaO-catalysts inactive. Fe/Al2O3 catalysts exhibit the highest catalytic activity, but give rise to scarce selectivity and large metallic impurity contents. Contrarily, using Fe/MgO and Fe/CaO catalysts leads to lower yields, but allows reducing impurities and remarkably improving selectivity and nanotube crystallinity. 相似文献
68.
Oriana Simonetti Oscar Cirioni Federico Mocchegiani Ivana Cacciatore Carmela Silvestri Leonardo Baldassarre Fiorenza Orlando Pamela Castelli Mauro Provinciali Marco Vivarelli Erika Fornasari Andrea Giacometti Annamaria Offidani 《International journal of molecular sciences》2013,14(8):16321-16332
We investigated the efficacy of tigecycline and FS8, alone or combined, in preventing prosthesis biofilm in a rat model of staphylococcal vascular graft infection. Graft infections were established in the back subcutaneous tissue of adult male Wistar rats by implantation of Dacron prostheses followed by topical inoculation with 2 × 107 colony-forming units of Staphylococcus aureus, strain Smith diffuse. The study included a control group, a contaminated group that did not receive any antibiotic prophylaxis, and three contaminated groups that received: (i) intraperitoneal tigecycline, (ii) FS8-soaked graft, and (iii) tigecycline plus FS8-soaked graft, respectively. Each group included 15 animals. The infection burden was evaluated by using sonication and quantitative agar culture. Moreover, an in vitro binding-study was performed to quantify the how much FS8 was coated to the surface of the prosthesis. Tigecycline, combined with FS8, against the adherent bacteria showed MICs (2.00 mg/L) and MBCs (4.00 mg/L) four-fold lower with respect to tigecycline alone in in vitro studies. The rat groups treated with tigecycline showed the lowest bacterial numbers (4.4 × 104 ± 1.2 × 104 CFU/mL). The FS8-treated group showed a good activity and significant differences compared to control group with bacterial numbers of 6.8 × 104 ± 2.0 × 104 CFU/mL. A stronger inhibition of bacterial growth was observed in rats treated with a combined FS8 and tigecycline therapy than in those that were singly treated with bacterial numbers of 101 CFU/mL graft. In conclusion, the ability to affect biofilm formation as well, its property to be an antibiotic enhancer suggests FS8 as alternative or additional agent to use in conjunction with conventional antimicrobial for prevention of staphylococcal biofilm related infection. 相似文献
69.
Review of book: Manuel Furer, Edward Nersessian, and Carmela Perri (Eds.) Controversies in contemporary psychoanalysis: Lectures from the faculty of the New York Psychoanalytic Association. Madison, CT: International Universities Press, 1998, xiv + 197 pp.. Reviewed by Antonio R. Virsida (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Kotoni D Ciogli A Molinaro C D'Acquarica I Kocergin J Szczerba T Ritchie H Villani C Gasparrini F 《Analytical chemistry》2012,84(15):6805-6813
A new chiral stationary phase for ultrahigh-pressure liquid chromatography (UHPLC) applications was prepared by covalent attachment of the Whelk-O1 selector to spherical, high-surface-area 1.7-μm porous silica particles. Columns of varying dimensions (lengths of 50, 75, 100, and 150 mm and internal diameters of 3.0 or 4.6 mm) were packed and characterized in terms of permeability, efficiency, retention, and enantioselectivity, using both organic and water-rich mobile phases. A conventional HPLC Whelk-O1 column based on 5.0-μm porous silica particles and packed in a 250 mm × 4.6 mm column was used as a reference. Van Deemter curves, generated with low-molecular-weight solutes on a 100 mm × 4.6 mm column packed with the 1.7-μm particles, showed H(min) (μm) and μ(opt) (mm/s) values of 4.10 and 5.22 under normal-phase and 3.74 and 4.34 under reversed-phase elution conditions. The flat C term of the van Deemter curves observed with the 1.7-μm particles allowed the use of higher-than-optimal flow rates without significant efficiency loss. Kinetic plots constructed from van Deemter data confirmed the ability of the column packed with the 1.7-μm particles to afford subminute separations with good efficiency and its superior performances in the high-speed regime, compared to the column packed with 5.0-μm particles. Resolutions in the time scale of seconds were obtained using a 50-mm-long column in the normal phase or polar organic mode. The intrinsic kinetic performances of 1.7-μm silica particles are retained in the Whelk-O1 chiral stationary phase, clearly demonstrating the potentials of enantioselective UHPLC in terms of high speed, throughput, and resolution. 相似文献