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741.
Cancer is a leading cause of death worldwide. The search for innovative therapeutic approaches is a principal focus of medical research. Vaccine strategies targeting a number of tumor-associated antigens are currently being evaluated. To date, none have garnered significant success. Purportedly, an immunosuppressive tumor microenvironment and the accumulation of regulatory T cells contribute to a lack of tumor vaccine efficacy. Aspartyl/asparaginyl β-hydroxylase (ASPH), a promising therapeutic target, is overexpressed in a variety of malignant tumors but is expressed negligibly in normal tissues. Computer analysis predicted that ASPH expresses four peptide sequences (epitopes) capable of stimulating regulatory T cell activity. The abolition of these putative regulatory T cell epitopes increased the CD4+ and CD8+ effector T cell responses to monocyte-derived dendritic cells pulsed with a modified, epitope-depleted version of ASPH in an ex vivo human lymphoid tissue-equivalent coculture system while simultaneously decreasing the overall number of FoxP3+ regulatory T cells. These findings suggest that the efficacy of all new vaccine candidates would profit from screening and eliminating potential tolerogenic regulatory T cell epitopes.  相似文献   
742.
This study investigated the diversity of yeast species associated with rotting wood in Brazilian Amazonian rainforests. A total of 569 yeast strains were isolated from rotting wood samples collected in three Amazonian areas (Universidade Federal do Amazonas-Universidade Federal do Amazonas [UFAM], Piquiá, and Carú) in the municipality of Itacoatiara, Amazon state. The samples were cultured in yeast nitrogen base (YNB)-d -xylose, YNB-xylan, and sugarcane bagasse and corncob hemicellulosic hydrolysates (undiluted and diluted 1:2 and 1:5). Sugiyamaella was the most prevalent genus identified in this work, followed by Kazachstania. The most frequently isolated yeast species were Schwanniomyces polymorphus, Scheffersomyces amazonensis, and Wickerhamomyces sp., respectively. The alpha diversity analyses showed that the dryland forest of UFAM was the most diverse area, while the floodplain forest of Carú was the least. Additionally, the difference in diversity between UFAM and Carú was the highest among the comparisons. Thirty candidates for new yeast species were obtained, representing 36% of the species identified and totaling 101 isolates. Among them were species belonging to the clades Spathaspora, Scheffersomyces, and Sugiyamaella, which are recognized as genera with natural xylose-fermenting yeasts that are often studied for biotechnological and ecological purposes. The results of this work showed that rotting wood collected from the Amazonian rainforest is a tremendous source of diverse yeasts, including candidates for new species.  相似文献   
743.
Digital light processing (DLP) enables the fabrication of complex 3D structures based on a photopolymerizable resin usually containing a photo initiator and an UV or photo absorber. The resin and thus the final properties of the printed structures can be adjusted by adding fillers like bioceramic powders relevant for bone-regeneration applications. Herein, a water-based and biocompatible poly(ethylene glycol diacrylate) (PEGDA) resin containing the photo initiator lithium-phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) enables the production of 3D structures via DLP. The addition of calcium magnesium phosphate cement (CMPC) powder, acting as photo absorber, leads to higher accuracy of the final structures. After curing the printed construct in a diammonium–hydrogen phosphate (DAHP) bath for hardening, the resulting mechanical properties can be adjusted without post-process sintering. Solid loading of up to 40 wt% CMPC powder is possible, and the resins are investigated regarding their rheological behavior and printability. The resulting constructs are analyzed in respect to their surface morphology using scanning electron microscope (SEM), porosity, phase composition using X-ray diffraction (XRD) methods, as well as mechanical properties influenced by the hardening process using DAHP for different durations.  相似文献   
744.
Polymersome-based biomimetic nanoreactors (PBNs) have generated great interest in nanomedicine and cell mimicry due to their robustness, tuneable chemistry, and broad applicability in biologically relevant fields. In this concept review, we mainly discuss the state of the art in functional polymersomes as biomimetic nanoreactors with membrane-controlled transport. PBNs that use environmental changes or external stimuli to adjust membrane permeability while maintaining structural integrity are highlighted. By encapsulating catalytic species, PBNs are able to convert inactive substrates into functional products in a controlled manner. In addition, special attention is paid to the use of PBNs as tailored artificial organelles with biomedical applications in vitro and in vivo, facilitating the fabrication of next-generation artificial organelles as therapeutic nanocompartments.  相似文献   
745.
The phosphorous-based flame retardant additives poly(m-phenylene methylphosphonate) (PMP) and resorcinol bis(diphenyl phosphate) (RDP) are reacted with bisphenol F and aniline–based benzoxazine (BF-a). DSC, rheological analysis, FT-IR, and soxhlet extraction reveal the covalent incorporation of both FR additives—initiating phenols in PMP structure as well as free phenols generated via transesterification reaction in the case of RDP. In contrast to PMP, RDP elongates the processing window but decreases the thermo–mechanical properties. Both additives increase the resistance in reactions against small flames with solely a phosphorous loading of 0.3 wt%, resulting in a V-0 rating and an improvement in the OI value by up to 2% for RDP and 4% for PMP. Both FRs reduce the heat release rate but increase the smoke production and the smoke toxicity in the case of RDP.  相似文献   
746.
In recent years, dual-cure chemistry has been exploited to realize interpenetrating networks (IPNs) that provide enhanced thermo-mechanical properties. In this contribution, photoinduced curing of (meth)acrylates is used to build the desired 3D structure, whereas the thermally triggered polymerization reaction of 2H-chromene functionalized building blocks is utilized to create the IPN. This strategy combines the advantages of traditional UV-curable monomers with high-performance thermosets. After the successful synthesis of the bispropargyl ether derivative, i.e., 4,4′-(propane-2,2-diyl)bis((ethynyloxy)benzene), its thermally induced conversion to the corresponding 2H chromene functionalized prepolymer is studied by Fourier-transform infrared spectroscopy and gel permeation chromatography. The network formation as well as the printability of various formulations containing different amounts of the thermo-curable building block is investigated. The obtained IPNs provide enhanced thermo-mechanical properties making these resins suitable for the additive manufacturing of functional 3D parts for high-performance applications.  相似文献   
747.
748.
The tribological performance of contacts within hydraulic pumps over a wide range of conditions is essential for the sustainability of mobile hydraulic systems. To reduce the energy consumption of hydraulic systems, mechanical losses and wear rates need to be reduced. Additionally, materials containing lead must also be replaced due to their environmental impact. In this study, the performance of different lead-free combinations of hydrogenated diamond-like carbon (hydr. DLC) coatings were investigated. For this purpose, the tribological behavior of hydr. DLC (Balinit DLC), ceramic-doped hydr. DLC (Balinit C), and ceramic bond-coated hydr. DLC (Balinit DLC Star) coatings on a nitride steel substrate were compared in tribometer tests.  相似文献   
749.
750.
Forschung im Ingenieurwesen - Nicht nur der Verbrennungsmotor eines Fahrzeuges emittiert Feinstaub, auch durch das Bremsen und Abrollen des Reifens entstehen solche gesundheitsschädlichen...  相似文献   
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