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101.
102.
Yeon-Ah Lee Hye-In Ji Sang-Hoon Lee Seung-Jae Hong Hyung-In Yang Myung Chul Yoo Kyoung Soo Kim 《Experimental & molecular medicine》2014,46(1):e72
This study was performed to evaluate the contribution of adiponectin to the production of interleukin (IL)-6, IL-8, vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-1 and MMP-13 in human endothelial cells and osteoblasts in arthritic joints. Cultured human umbilical vascular endothelial cells (HUVECs) and osteoblasts were stimulated with adiponectin (1 or 10 μg ml−1) or IL-1β (0.1 ng ml−1) in the presence or absence of hypoxia for 24 h. The protein expression patterns were examined by analyzing culture supernatants using the enzyme-linked immunosorbent assay (ELISA). Adiponectin significantly stimulated the production of VEGF, MMP-1 and MMP-13 in osteoblasts but not in endothelial cells, whereas it significantly stimulated the production of IL-6 and IL-8 in both endothelial cells and osteoblasts. The increase in VEGF production induced by adiponectin was significantly greater than that induced by IL-1β. The production of IL-6 and IL-8 in adiponectin-stimulated endothelial cells was approximately 10-fold higher than that in IL-1β-stimulated endothelial cells; in osteoblasts, adiponectin-induced IL-6 and IL-8 secretion was approximately twofold higher than that induced by IL-1β. In addition, IL-8 production in endothelial cells was approximately sevenfold higher than in osteoblasts. However, IL-6 levels were similar between the two cell types, suggesting that adiponectin may be involved in the production of IL-8 in endothelial cells, which may have an important role in neutrophil recruitment to arthritic joints. Furthermore, the increases in protein expression induced by adiponectin were differentially regulated by hypoxia. In conclusion, adiponectin has a more important role than does IL-1β in the production of mediators that drive synovitis and joint destruction in endothelial cells and osteoblasts at physiological concentrations. 相似文献
103.
Helical Carbon and Graphite Films Prepared from Helical Poly(3,4‐ethylenedioxythiophene) Films Synthesized by Electrochemical Polymerization in Chiral Nematic Liquid Crystals 下载免费PDF全文
Dr. Satoshi Matsushita Bairu Yan Shinsuke Yamamoto Dr. Yong Soo Jeong Prof. Kazuo Akagi 《Angewandte Chemie (International ed. in English)》2014,53(6):1659-1663
Helical carbon and graphite films from helical poly(3,4‐ethylenedioxythiophene) (H‐PEDOT) films synthesized through electrochemical polymerization in a chiral nematic liquid‐crystal (N*‐LC) field are prepared. The microscope investigations showed that the H‐PEDOT film synthesized in the N*‐LC has large domains of one‐handed spiral morphology consisting of fibril bundles. The H‐PEDOT films exhibited distinct Cotton effects in circular dichroism spectra. The highly twisted N*‐LC with a helical pitch of smaller than 1 μm produced the H‐PEDOT film with a highly ordered morphology. The spiral morphologies with left‐ and right‐handed screws were observed for the carbon films prepared from the H‐PEDOT films at 800 °C and were well correlated with the textures and helical pitches of the N*‐LCs. The spiral morphologies of the precursors were also retained even in the graphite films prepared from the helical carbon films at 2600 °C. 相似文献
104.
Soo Chool Lee Min Sun Cho Suk Yong Jung Chong Kul Ryu Jae Chang Kim 《Adsorption》2014,20(2-3):331-339
A range of potassium-based alumina sorbents were fabricated by impregnation of alumina with K2CO3 to examine the effects of the structural and textural properties of alumina on the CO2 sorption and regeneration properties. Alumina materials, which were used as supports, were prepared by calcining alumina at various temperatures (300, 600, 950, and 1,200 °C). The CO2 sorption and regeneration properties of these sorbents were examined during multiple tests in a fixed-bed reactor in the presence of 1 vol% CO2 and 9 vol% H2O. The regeneration capacities of the potassium-based alumina sorbents increased with increasing calcination temperature of alumina. The formation of KHCO3 increased with increasing calcination temperature during CO2 sorption, whereas the formation of KAl(CO3)(OH)2, which is an inactive material, decreased. These results is due to the fact that the structure of alumina by the calcination temperature is related directly to the formation of the by-product [KAl(CO3)(OH)2]. The structure of alumina plays an important role in enhancing the regeneration capacity of the potassium-based alumina sorbent. Based on these results, a new potassium-based sorbent using δ-Al2O3 as a support was developed for post-combustion CO2 capture. This sorbent maintained a high CO2 capture capacity of 88 mg CO2/g sorbent after two cycles. In particular, it showed a faster sorption rate than the other potassium-based alumina sorbents examined. 相似文献
105.
Water disinfection activity of cellulose filters treated with polycarboxylic acid and aromatic amine
A cellulose filter for water disinfection was developed using a polycarboxylic acid and an aromatic amine via a simple process with water as a solvent. 1,2,3,4-Butanetetracarboxylic acid/m-phenylenediamine solution was applied to cellulose filters using a pad–dry–curing process. The surfaces of treated cellulose filters were examined by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The liquid permeabilities of treated cellulose filters were determined by capillary flow porometry, and their water disinfection efficacies were measured by non-pressure-driven filtration. Chlorinated cellulose filters disinfected Escherichia coli- and Staphylococcus aureus-containing solutions to a much higher degree than observed for nonchlorinated cellulose filters. 相似文献
106.
Stereocomplexation is one of the approaches to improve polylactide's properties. Along with improving its properties, it also limits stereocomplex formation through solution and stereocomplex memory. The graft structure and presence of nanoparticles have a synergetic effect, improving the stereocomplex formation and its memory. The bio-stereocomplex-nanocomposite materials are generated by stereocomplexation of polylactide-graft-acetylated cellulosic nanowhiskers in the solution. The graft structure containing well-distributed acetylated cellulose nanowhiskers results in unusual stereocomplexation in the solution and influences the stereocomplex memory of the bio-stereocomplex-nanocomposite materials. Perfect stereocomplexes are easily obtained in a relatively short mixing time (5 min) from various solution concentrations up to 20 % (w/v). The bio-stereocomplex-nanocomposites have excellent stereocomplex memory to re-form the stereocomplex after melting, which is the main limitation of stereocomplex materials in industrial processes. This fully bio-based material is a potential ecofriendly candidate for the future. 相似文献
107.
Dr. Jae‐Il Jung Dr. Hu Young Jeong Jang‐Soo Lee Dr. Min Gyu Kim Prof. Dr. Jaephil Cho 《Angewandte Chemie (International ed. in English)》2014,53(18):4582-4586
La0.3(Ba0.5Sr0.5)0.7Co0.8Fe0.2O3?δ is a promising bifunctional perovskite catalyst for the oxygen reduction reaction and the oxygen evolution reaction. This catalyst has circa 10 nm‐scale rhombohedral LaCoO3 cobaltite particles distributed on the surface. The dynamic microstructure phenomena are attributed to the charge imbalance from the replacement of A‐site cations with La3+ and local stress on Co‐site sub‐lattice with the cubic perovskite structure. 相似文献
108.
Dr. Hoon Hyun Dr. Hideyuki Wada Dr. Kai Bao Dr. Julien Gravier Dr. Yogesh Yadav Dr. Matt Laramie Dr. Maged Henary Dr. John V. Frangioni Dr. Hak Soo Choi 《Angewandte Chemie (International ed. in English)》2014,53(40):10668-10672
The conventional method for creating targeted contrast agents is to conjugate separate targeting and fluorophore domains. A new strategy is based on the incorporation of targeting moieties into the non‐delocalized structure of pentamethine and heptamethine indocyanines. Using the known affinity of phosphonates for bone minerals in a model system, two families of bifunctional molecules that target bone without requiring a traditional bisphosphonate are synthesized. With peak fluorescence emissions at approximately 700 or 800 nm, these molecules can be used for fluorescence‐assisted resection and exploration (FLARE) dual‐channel imaging. Longitudinal FLARE studies in mice demonstrate that phosphonated near‐infrared fluorophores remain stable in bone for over five weeks, and histological analysis confirms their incorporation into the bone matrix. Taken together, a new strategy for creating ultra‐compact, targeted near‐infrared fluorophores for various bioimaging applications is described. 相似文献
109.
Jun Myung Kim So Hyeong Sohn Noh Soo Han Prof. Seung Min Park Prof. Joohoon Kim Prof. Jae Kyu Song 《Chemphyschem》2014,15(14):2917-2921
Direct evidence for the blue luminescence of gold nanoclusters encapsulated inside hydroxyl‐terminated polyamidoamine (PAMAM) dendrimers was provided by spectroscopic studies as well as by theoretical calculations. Steady‐state and time‐resolved spectroscopic studies showed that the luminescence of the gold nanoclusters consisted largely of two electronic transitions. Theoretical calculations indicate that the two transitions are attributed to the different sizes of the gold nanoclusters (Au8 and Au13). The luminescence of the gold nanoclusters was clearly distinguished from that of the dendrimers. 相似文献
110.
Dae Woo Ihm Soo Young Park Cheol Gyu Chang Yoon Sung Kim Hwan Kwang Lee 《Journal of polymer science. Part A, Polymer chemistry》1996,34(14):2841-2850
The effects of transesterification on the miscibility of poly(ethylene terephthalate)/poly(ethylene 2,6-naphthalate) were studied. Blends were obtained by solution precipitation at room temperature to avoid transesterification during blend preparation. The physical blends and transesterified products were analyzed by wide-angle x-ray scattering, differential scanning calorimetry, and nuclear magnetic resonance spectroscopy. It was found that the physical blends are immiscible and when the extent of transesterification reaches 50% of the completely randomized state, independent of blend composition, the blends are not crystallizable and show a single glass transition temperature between those of starting polymers. The interchange reactions were significantly influenced by annealing temperature and time but negligibly by blend composition. © 1996 John Wiley & Sons, Inc. 相似文献