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861.
Architect Marta Pozo Gil , who leads the Sustainability Department at MVRDV, draws on a correlation between people's retreat indoors, with urban populations becoming increasingly divorced from nature, and the growing ambitions for ‘green’ cities and the ensuing benefits they bring to our quality of life. How might it, though, be possible to realise such a vision? Pozo Gil describes some of MVRDV's lesser-known projects that weave nature into the city.  相似文献   
862.
In order to successfully cure patients with prostate cancer (PCa), it is important to detect the disease at an early stage. The existing clinical biomarkers for PCa are not ideal, since they cannot specifically differentiate between those patients who should be treated immediately and those who should avoid over-treatment. Current screening techniques lack specificity, and a decisive diagnosis of PCa is based on prostate biopsy. Although PCa screening is widely utilized nowadays, two thirds of the biopsies performed are still unnecessary. Thus the discovery of non-invasive PCa biomarkers remains urgent. In recent years, the utilization of urine has emerged as an attractive option for the non-invasive detection of PCa. Moreover, a great improvement in high-throughput “omic” techniques has presented considerable opportunities for the identification of new biomarkers. Herein, we will review the most significant urine biomarkers described in recent years, as well as some future prospects in that field.  相似文献   
863.
Platinum nanoparticles (NP-Pt) are noble metal nanoparticles with unique physiochemical properties that have recently elicited much interest in medical research. However, we still know little about their toxicity and influence on general health. We investigated effects of NP-Pt on the growth and development of the chicken embryo model with emphasis on brain tissue micro- and ultrastructure. The embryos were administered solutions of NP-Pt injected in ovo at concentrations from 1 to 20 μg/ml. The results demonstrate that NP-Pt did not affect the growth and development of the embryos; however, they induced apoptosis and decreased the number of proliferating cells in the brain tissue. These preliminary results indicate that properties of NP-Pt might be utilized in brain cancer therapy, but potential toxic side effects must be elucidated in extensive follow-up research.  相似文献   
864.
Rainwater was collected at the Portuguese west coast between September 2008 and September 2009, and analysed for pH, conductivity, and Cl, NO3, SO42−, and NH4+ concentrations. Results of rainwater chemical composition were compared with those obtained at the same site between 1986 and 1989. In both collection periods rainwater was predominantly (≈ 80%) associated to oceanic air masses. The rainwater concentration of H+ was in the same range as twenty years ago. A clear decrease of non sea salt sulphate (NSS-SO42−) was observed in 2008-2009 relatively to 1986-1989, not only in samples with origin in central and northern Europe, but also in samples from Atlantic Ocean and Mediterranean. This decrease indicates that SO2 emissions were reduced, which may be due to a lower content of sulphur in oil by-products. A decrease was also observed in NH4+ concentration in 2008-2009. On the contrary an increase of NO3 concentration was observed for samples of all origins in 2008-2009 relatively to 1986-1989, which was particularly high (more than 3 fold) for samples with origin in Atlantic Ocean, suggesting the incorporation of this ion by rainout at the sampling site. The contribution of local sources is indeed suggested by the moderate negative correlation of NH4+, NO3 and NSS-SO42− with rainwater volume. The high increase of NO3 concentration can be attributed to the increase of local vehicular and industrial emissions in the sampling area.  相似文献   
865.
An investigation was conducted to determine the role of Ni particles in the WC-Co coating produced with the supersonic method on microstructure, mechanical, and wear properties in a system of type: WC-Co coating/ductile cast iron. The microstructure of the thermal-sprayed WC-Co + Ni coating was characterized by scanning electron and transmission electron microscopes as well as the analysis of chemical and phase composition in microareas (EDS, XRD). The microstructure of the WC-Co + Ni coating consisted of large, partially molten Ni particles and very fine grains of WC embedded in cobalt matrix, coming to the size of nanocrystalline. Moreover, the results were discussed in reference to examination of bending strength considering cracking and delamination in the system of (WC-Co + Ni)/ductile cast iron as well as hardness and wear resistance of the coating. It was found that the addition of Ni particles was significantly increase resistance to cracking and wear behavior in the studied system.  相似文献   
866.
Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract.  相似文献   
867.
The aim of this study was to select effective and safe microbiocides for the disinfection and protection of historical wooden surfaces at the former Auschwitz II-Birkenau concentration and extermination camp. We tested seven active compounds against bacteria and moulds, of which didecyldimethylammonium chloride and N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine were effective even at 0.02%–2%. Subsequently, eight microbiocides containing the selected active ingredients were chosen and applied three times on the surface of wood samples colonized by bacteria and moulds. ABM-1 and ABM-2—6% solution; Rocima 101—8%; Preventol R 80—12%; Acticide 706 LV—15% and Boramon—30% were the most effective disinfectants. Under laboratory conditions, ABM-1, Boramon and Rocima 101 ensured antimicrobial protection of new wood samples for six months. In situ, 30% Boramon and 8% Rocima 101 applied by spraying effectively protected the historical wood from bacterial and mould growth for 12 and 3 months, respectively. Colour and luminance of the new wood were not altered after exposure to the biocides. Boramon and Rocima 101, applied by the spraying method, caused no significant change in the colour of the historical wood. Results from this study were used to develop a procedure for the protection of wood in historical buildings against biodeterioration.  相似文献   
868.
A bifunctional metal organic framework catalyst containing palladium and copper(II) benzene‐1,3,5‐tricarboxylate – MOF‐Cu(BTC)‐[Pd] – has been prepared. This catalyst enables the performance of the tandem Sonogashira/click reaction starting from 2‐iodobenzylbromide, sodium azide and alkynes to produce 8H‐[1,2,3]triazolo[5,1‐a]isoindoles with good yields under mild reaction conditions.  相似文献   
869.
ABSTRACT: Porous silicon microcavity (PSiMc) structures were used to immobilize the photosynthetic reaction center (RC) purified from the purple bacterium Rhodobacter sphaeroides R-26. Two different binding methods were compared by specular reflectance measurements. Structural characterization of PSiMc was performed by scanning electron microscopy and atomic force microscopy. The activity of the immobilized RC was checked by measuring the visible absorption spectra of the externally added electron donor, mammalian cytochrome c. PSi/RC complex was found to oxidize the cytochrome c after every saturating Xe flash, indicating the accessibility of specific surface binding sites on the immobilized RC, for the external electron donor. This new type of bio-nanomaterial is considered as an excellent model for new generation applications of silicon-based electronics and biological redox systems.  相似文献   
870.
Food Science and Biotechnology - This study aims at the synthesis of hexyl butyrate by Candida rugosa lipase (CRL) immobilized on Diaion HP 20. The lipase load used was...  相似文献   
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