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921.
Teofil Jesionowski Agnieszka Andrzejewska Andrzej Krysztafkiewicz 《Coloration Technology》2008,124(3):165-172
Removal of CI Basic Blue 9 or CI Basic Red 5 from model aqueous solutions has been studied with spherical silica precipitated in an emulsion system used as an adsorbent. The process of removal of the dye impurities has been studied for the dyes in a wide range of concentrations (50–2000 mg dm−3 ) in model systems. The degree of dye adsorption, chemical stability of the pigments obtained and their detailed physicochemical and morphological characterisation have been ascertained. In particular, the dye removal method proposed has been found to be highly effective in removing CI Basic Blue 9 (99.9%). The degree of dye extraction from the silica (SiO2 ) surface at the dye concentration in the model solutions in the range 1000–2000 mg dm−3 did not exceed 1.0%. The pigment composites produced are characterised by high uniformity of the particles (polydispersity index = 0.005) with the diameters ranging from 360 to 510 nm. The pigment particles are spherical in shape and of intense blue or red colour. 相似文献
922.
Bingbing Liu Yuanyuan Hou Lin Wang Dedi Liu Shidan Yu Bo Zou Tian Cui Guangtian Zou Agnieszka Iwasiewicz-Wabnig Bertil Sundqvist 《Diamond and Related Materials》2008,17(4-5):620-623
In this paper, C60 nanosheets with polymeric phases have been obtained under various high pressures and high temperatures, including orthorhombic and tetragonal polymeric phases. The structures have been identified and compared with those of nanorods by photoluminescence and Raman spectroscopies. The main fluorescence band shifted from 1.70 eV in the monomeric phase to near infrared in the polymeric phase when pressure and temperature were increased. The difference of photoluminescence and Raman spectra between nanosheets and nanorods samples treated under the same conditions is probably caused by different polymerization degree in these samples because of different shapes. 相似文献
923.
Vincent Barlier Véronique Bounor-Legaré Gisèle Boiteux Joel Davenas Agnieszka Slazak Andrzej Rybak Jaroslaw Jung 《Synthetic Metals》2009,159(5-6):508-512
TiO2:poly(N-vinylcarbazole) (PVK) bulk-heterojunctions (BHJ) have been elaborated from a blend of a TiO2 precursor with the polymer in solution. The TiO2 precursor is hydrolyzed with the surrounding air humidity in thin film. Titanium isopropoxide [Ti(iOPr)4] and Tetrakis (9H-carbazole-9-yl-ethyl-oxy) titanium [Ti(OeCarb)4] were used as TiO2 precursor. Photogeneration quantum yield in BHJ of TiO2:PVK were determined by the surface potential decay (SPD) technique. Photovoltaic effect was studied in ITO/PEDOT:PSS/TiO2:PVK/Al structures. It was found that the photovoltaic performance is strongly dependent on the homogeneity of the blends. The improved dispersion of the TiO2 phase obtained with the precursor bearing a carbazole group allows efficient electron transport and fill factor enhancement of the photovoltaic devices. 相似文献
924.
Katarzyna Szewczyk Wioleta Pietrzak Katarzyna Klimek Magorzata Miazga-Karska Agnieszka Firlej Marek Flisiski Anna Grzywa-Celiska 《International journal of molecular sciences》2021,22(12)
Skin aging is a natural, unavoidable, and complex process caused by oxidative stress. As a consequence, it leads to an increase in the activation of extracellular matrix disruption enzymes and DNA damage. The search for natural sources that inhibit these mechanisms can be a good approach to prevent skin aging. The purpose of our study was to evaluate the composition of flavonoids and phenolic acids in the extracts obtained from the flowers, roots, and leaves of Eutrema japonicum cultivated in Poland. Then, the resultant extracts were subjected to an assessment of antioxidant, anti-collagenase, anti-elastase, anti-hyaluronidase, antibacterial, and cytotoxic properties. It was demonstrated that the extract from the flowers had the highest content of flavonoid glycosides (17.15 mg/g DE). This extract showed the greatest antioxidant, anti-collagenase, anti-elastase, and anti-hyaluronidase activities compared to the other samples. Importantly, the collagenase inhibitory activity of this extract (93.34% ± 0.77%) was better than that of positive control epigallocatechin gallate (88.49% ± 0.45%). An undeniable advantage of this extract was also to possess moderate antibacterial properties and no cytotoxicity towards normal human skin fibroblasts. Our results suggest that extracts from E. japonicum flowers may be considered as a promising antiaging compound for applications in cosmetic formulations. 相似文献
925.
Magdalena Hasik Wincenty Turek Anna Nyczyk Edyta Stochmal Andrzej Bernasik Agnieszka Sniechota Agnieszka Sołtysek 《Catalysis Letters》2009,127(3-4):304-311
Composites of polyaniline (PANI) or polypyrrole (PPy) doped with chloride ions and Pt or Rh particles were prepared by chemical reduction of metal ions conducted in the presence of the polymers. Based on X-ray diffraction studies it was established that the composites contained metal nanoparticles (5–9 in size). However, according to SEM investigations metal particles were agglomerated (40 nm–1.1 μm in size). Redox activity of the composites in the catalytic isopropyl alcohol conversion was ca. ten times higher than the acid–base one. Pt dispersed in polymer matrices showed higher catalytic activity than Rh. PPy doped with chloride ions had a promoting effect on the activity of Pt catalysts. 相似文献
926.
Anita A.
liwiska Agnieszka Biaek Renata Orowska Dariusz Makowski Katarzyna Sykowska-Baranek Agnieszka Pietrosiuk 《International journal of molecular sciences》2021,22(11)
Polyscias filicifolia (Araliaceae) is broadly used in traditional medicine in Southeast Asia due to its antimicrobial, immunomodulating and cytotoxic activities. The main groups of compounds responsible for pharmacological effects are believed to be oleanolic triterpene saponins. However, Polyscias plants demonstrate relatively slow growth in natural conditions, which led to applying a developing sustainable source of plant material via primary (PSE), secondary (DSE) and direct somatic embryogenesis from DSE (TSE). The AFLP and metAFLP genotyping resulted in 1277 markers, amplified by a total of 24 pairs of selective primers. Only 3.13% of the markers were polymorphic. The analysis of variance showed that the PSE and TSE regenerants differed only in terms of root number, while the DSE plantlets differed for all studied morphological characteristics. Further, the chemical analysis revealed that oleanolic acid (439.72 µg/g DW), ursolic acid (111.85 µg/g DW) and hederagenin (19.07 µg/g DW) were determined in TSE regenerants. Our results indicate that direct somatic embryogenesis ensures the production of homogeneous plant material, which can serve as a potential source of triterpene compounds. Plants obtained via somatic embryogenesis could also be reintroduced into the natural environment to protect and preserve its biodiversity. 相似文献
927.
Niobium-containing siliceous-MSU-X mesoporous molecular sieves have been prepared according to an original pathway by the reaction between low-cost niobium species (ammonium trisoxalate complex of niobium (V)), silica precursor (tetraethyl orthosilicate), and biodegradable surfactant in strong acidic, acidic or almost neutral medium. The selective oxidation of several terpenes and terpenoids (geraniol, limonene, α-terpineol) using hydrogen peroxide as an oxidant agent over novel Nb-catalysts is studied in this work. A variety of (Nb)MSU-X and (Ru,Nb)MSU-X materials prepared under different conditions has been employed (supermicroporous/mesoporous molecular sieves) for this purpose. The structure–function relationships in these catalysts are reported. 相似文献
928.
929.
930.
The effects of high magnetic field armealihng on the morphology and texture of pulsed-electrodeposited Co-Ni-P films were investigated by field emission scanning electronic microscopy(FE-SEM),atomic force microscopy(AFM)and X-ray diffraction(XRD).The as-deposited film with cluster structural on a rough surface changed into non-uniform and bigger nanocrystalline during the no-field annealing due to a recrystallization process.Post-deposition annealing under a magnetic field favored to form a more homogeneous surface with smaller grain size and lower roughness.The magneto-induced a mixed phase structure including fcc-Ni,hcp-Co and fcc-CoNiP appeared in the case of the films annealed at a 9T magnetic field.The possible overlapping effects such as diffusion and recrystallization obtained by the magnetic field annealing on the morphology evolution and on the phase transformation in the films were interpreted. 相似文献