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Scaglione S Guarino V Sandri M Tampieri A Ambrosio L Quarto R 《Journal of materials science. Materials in medicine》2012,23(1):117-128
Bio-inspired materials with controlled topography have gained increasing interest in regenerative medicine, because of their ability to reproduce the physical features of natural extracellular matrix, thus amplifying certain biological responses both in vitro and in vivo, such as contact guidance and differentiation. However, information on the ability to adapt this high cell potential to 3D scaffolds, effective to be implanted in clinical bone defect, is still missing. Here, we examine the pattern of bone tissue generated within the implant in an ectopic model, seeding bone marrow progenitor cells onto PCL-MgCHA scaffolds. This composite material presented a porous structure with micro/nanostructured surfaces obtained by combining phase inversion/salt leaching and electrospinning techniques. Histological analysis of grafts harvested after 1-2-6 months from implantation highlights an extent of lamellar bone tissue within interconnected pores of fibre coated PCL-MgCHA composites, whereas uncoated scaffolds displayed sparse deposition of bone. Pure PCL scaffolds did not reveal any trace of bone for the overall 6 months of observation. In conclusion, we show that a structural modification in scaffold design is able to enhance bone regeneration possibly mimicking some physiological cues of the natural tissue. 相似文献
993.
This paper presents a new algorithm for electrocardiogram (ECG) signal compression based on local extreme extraction, adaptive hysteretic filtering and Lempel-Ziv-Welch (LZW) coding. The algorithm has been verified using eight of the most frequent normal and pathological types of cardiac beats and an multi-layer perceptron (MLP) neural network trained with original cardiac patterns and tested with reconstructed ones. Aspects regarding the possibility of using the principal component analysis (PCA) to cardiac pattern classification have been investigated as well. A new compression measure called "quality score," which takes into account both the reconstruction errors and the compression ratio, is proposed. 相似文献
994.
Monica Monici Francesca Cialdai Giovanni Romano Paola Antonia Corsetto Angela Maria Rizzo Anna Caselli Francesco Ranaldi 《Microgravity science and technology》2013,25(1):35-42
Microgravity-induced muscle atrophy is a problem of utmost importance for the impact it may have on the health and performance of astronauts. Therefore, appropriate countermeasures are needed to prevent disuse atrophy and favour muscle recovery. Muscle atrophy is characterized by loss of muscle mass and strength, and a shift in substrate utilization from fat to glucose, that leads to a reduced metabolic efficiency and enhanced fatigability. Laser therapy is already used in physical medicine and rehabilitation to accelerate muscle recovery and in sports medicine to prevent damages produced by metabolic disturbances and inflammatory reactions after heavy exercise. The aim of the research we present was to get insights on possible benefits deriving from the application of an advanced infrared laser system to counteract deficits of muscle energy metabolism and stimulate the recovery of the hypotrophic tissue. The source used was a Multiwave Locked System (MLS) laser, which combines continuous and pulsed emissions at 808 nm and 905 nm, respectively. We studied the effect of MLS treatment on morphology and energy metabolism of C2C12 cells, a widely accepted myoblast model, previously exposed to microgravity conditions modelled by a Random Positioning Machine. The MLS laser treatment was able to restore basal levels of serine/threonine protein phosphatase activity and to counteract cytoskeletal alterations and increase in glycolytic enzymes activity that occurred following the exposure to modelled microgravity. In conclusion, the results provide interesting insights for the application of infrared laser in the treatment of muscle atrophy. 相似文献
995.
Maria Concetta Tenuta Jianbo Xiao Monica Rosa Loizzo Annabelle Dugay 《Critical reviews in food science and nutrition》2019,59(6):864-881
AbstractIn addition to nutrients, plant foods contain compounds that may provide additional health benefits improving the quality of life. Species from Arbutus genus (Ericaceae) represent a promising source of healthy phytochemicals. Bioactive compounds including such as anthocyanins, iridoids, phenols, triterpenes, sterols, and fatty acids are reported from Arbutus species. Some Arbutus species revealed promising biological activities including antioxidant, anti-inflammatory, anti-proliferative, anti-diabetic, and antimicrobial activities, and deserve for that reason further consideration for new drug discovery. However, only few species are investigated scientifically for their chemical profile and biological activities. The aim of this article is to summarize the current knowledge of the components and biological properties of Arbutus species common in Mediterranean area, as well as the future prospects on their applications as potentially valuable products. 相似文献
996.
Luminescent calcium phosphate bioceramics doped with europium derived from fish industry byproducts
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Clara Piccirillo Alessio Adamiano David M. Tobaldi Marco Montalti Jeannette Manzi Paula M. Lima Castro Silvia Panseri Monica Montesi Simone Sprio Anna Tampieri Michele Iafisco 《Journal of the American Ceramic Society》2017,100(8):3402-3414
The recovery of valuable compounds from byproducts is at present a priority topic for social, environmental, and economic reasons. In this work we report for the first time the preparation of luminescent calcium phosphate (CaP) bioceramics from waste codfish bones. Codfish bones were treated in aqueous Eu(NO3)3 solutions of different concentrations, followed by thermal treatment at either 700°C or 1100°C. The resulting materials consisted of hydroxyapatite (HAp), β‐tricalcium phosphate (β‐TCP) and a small amount of Eu2O3. Chemical and structural characterization showed that the Eu ions were successfully introduced into the bones and, hence, in the thermally treated CaP phases obtained from them, although mainly in the β‐TCP lattice. Photoluminescence investigation revealed that all the materials are luminescent, with samples treated at 1100°C having more intense luminescence than those prepared at 700°C. In vitro evaluation of cell‐materials interaction indicated that all the samples displayed good cytocompatibility toward osteoblast cells. This work demonstrates that a simple and effective process, employing Eu as a dopant, can convert fish industry byproducts into highly valuable luminescent CaP bioceramics, having potential applications in biology and medicine for bio‐imaging. 相似文献
997.
Andro Mondala Rafael Hernandez Todd French Linda McFarland Darrell Sparks William Holmes Monica Haque 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(1):33-41
BACKGROUND: The effect of acetic acid, a lignocellulose hydrolysis by‐product, on lipid accumulation by activated sludge cultures grown on glucose was investigated. This was done to assess the possible application of lignocellulose as low‐cost and renewable fermentation substrates for biofuel feedstock production. RESULTS: Biomass yield was reduced by around 54% at a 2 g L?1 acetic acid dosage but was increased by around 18% at 10 g L?1 acetic acid dosage relative to the control run. The final gravimetric lipid contents at 2 and 10 g L?1 acetic acid levels were 12.5 ± 0.7% and 8.8 ± 3.2% w/w, respectively, which were lower than the control (17.8 ± 2.8% w/w). However, biodiesel yields from activated sludge grown with acetic acid (5.6 ± 0.6% w/w for 2 g L?1 acetic acid and 4.2 ± 3.0% w/w for 10 g L?1 acetic acid) were higher than in raw activated sludge (1–2% w/w). The fatty acid profiles of the accumulated lipids were similar with conventional plant oil biodiesel feedstocks. CONCLUSIONS: Acetic acid enhanced biomass production by activated sludge at high levels but reduced lipid production. Further studies are needed to enhance acetic acid utilization by activated sludge microorganisms for lipid biosynthesis. Copyright © 2011 Society of Chemical Industry 相似文献
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