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931.
Lee SW Kim IJ Jeong BY Choi MH Kim JY Kwon KH Lee JW Yu A Shin MG 《Electrophoresis》2012,33(12):1863-1872
The response criteria for complete remission (CR) in acute myeloid leukemia (AML) are currently based on morphology and blood cell counts. However, these criteria are insufficient to establish a diagnosis in cases with poor quality bone marrow (BM) samples demonstrating a loss of cellular morphology. We investigated whether the sera of patients contained biomarkers that indicate disease response status. First, we performed multidimensional liquid chromatography-differential gel electrophoresis (MDLC-DIGE) to generate protein profiles of two pooled, paired serum samples from patients who had achieved CR; one collected at diagnosis (PreCR) and the other collected after chemotherapy (CR). Then, with the biomarker candidates found, ELISA was carried out for individual PreCR and CR samples, and for other verification sets including nonremission (NR) patients and normal samples. We selected two proteins, complement factor H (CFH) and apolipoprotein H (ApoH), with dye (Cy) ratios showing greater than 2.0-fold differences between the pooled samples. ELISA showed that CFH and ApoH are useful for distinguishing between the recovered (CR and normal) and nonrecovered (PreCR, PreNR, and NR) states in AML (p <0.001). We successfully applied a protein profiling technology of MDLC-DIGE and LC-MS/MS to discover two biomarkers for CR which needs further validation for a clinical setting. 相似文献
932.
Hong YH Jung EY Shin KS Kim TY Yu KW Chang UJ Suh HJ 《Applied biochemistry and biotechnology》2012,166(1):165-175
Ultraviolet B (UVB) irradiation may induce the acceleration of skin aging. The purpose of this study was to develop an effective
formulation containing tannase-converted green tea extract (FTGE) to inhibit UVB-induced oxidative damage. Significant (p < 0.05) prevention of the reduced form of glutathione (GSH) depletion was observed in mice treated with FTGE. The hydrogen
peroxide levels of mice treated with FTGE were similar to those of UVB non-irradiated mice. No significant difference was
observed between No UVB control and FTGE mice. Also, mice treated with FTGE had significant (p < 0.05) decreases in thiobarbituric acid-reactive substance levels by lipid peroxidation compared with No UVB control mice.
Our data suggest that this formulation may be effective in protecting skin from UVB photodamage. 相似文献
933.
Farzana Ahmad Muhammad Jamil Lee Jin Woo Young Jae Jeon 《Colloid and polymer science》2012,290(7):599-606
Acrylic polyethylene glycol(PEG)-based polymer-dispersed liquid crystal (PDLC) films have been fabricated to investigate the
effect of intermolecular interactions on PDLC performance. For this purpose, the amphiphilic liquid crystal and polymers are
selected as PDLC composite materials. The acrylic PEG contents are varied from 0 to 66.66 mol wt.% in order to understand
the effects of different levels of additions on the microstructure and electro-optical properties of the PDLC films. For this
intention, polarized optical microscopy and UV–vis spectroscopy are used. The extent of phase separation and anchoring energy
are also examined using Fourier transform infrared (FTIR) spectroscopy and contact angle measurements in consequence of acrylic
PEG addition. The contrast ratio, threshold voltage, as well as saturation voltage, tended to increase with the addition of
acrylic PEG. The molecular affinity involved in the polymer matrix and LC molecules affected the phase separation which is
responsible for the formation of domain size; this accordingly changed the electro-optical properties of PDLC film. 相似文献
934.
Lee DJ Cho KY Jang S Song YS Youn JR 《Langmuir : the ACS journal of surfaces and colloids》2012,28(28):10488-10494
We explored a liquid slip, referred to as the Navier slip, at liquid-solid interface. Such a slip is provoked by the physicochemical features of the liquid-solid system. The goal of this study was to investigate the effect of a nanoengineered surface structure on liquid slip by fabricating the self-assembly structure of nano Zinc oxide (n-ZnO). We have also examined how the liquid-solid surface interaction controlled by hydrophobic chemical treatment affects the liquid slip. The findings showed that liquid slip increases with decreasing the characteristic length scales (e.g., channel height and depth), resulting in drag reduction. It was also found that dewetted (Cassie) state due to the generation of air gap developed by n-ZnO was more critical for the liquid slip than the minimization of interface interaction. The linear and nonlinear Navier slip models showed that liquid slip behavior is more obvious when increasing the nonlinearity. This study will contribute to understanding of the underlying physics behind fluid slip phenomena, such as the Navier slip for Newtonian liquids and Maxwell's slip for Newtonian gases. 相似文献
935.
Lee SJ An HH Han WB Kim HS Yoon CS 《Langmuir : the ACS journal of surfaces and colloids》2012,28(30):10980-10987
Coarsening behavior of the Au nanoparticles produced by thermal evaporation of Au onto a liquid crystalline lipid (1,2-dioleoyl-3-trimethylammonium-propane, DOTAP) membrane was investigated by subjecting the nanoparticle-embedded DOTAP membrane to two different annealing conditions (at 100 °C under no humidity and at 20 °C and 80% relative humidity). Although the coarsening rate was relatively slow because of the low temperature (from 5.6 nm in the as-deposited state to ~7 nm after 30 h), it was identified that at 100 °C without humidity the Au nanoparticles resulted in shape refinement whereas the high humidity at 20 °C induced self-organization of the nanoparticles into a monolayer. It was also found that annealing in both cases tended to segregate the lipid molecules from the nanoparticle array and forced the nanoparticles into a tighter area. In the case of the high-humidity sample, the lipid segregation eventually led to extensive coalescence of the Au nanoparticles. 相似文献
936.
Seung-Chan Baek Ki-Won Jun Yun-Jo Lee Jae Dong Kim Dal Young Park Kwan-Young Lee 《Research on Chemical Intermediates》2012,38(6):1225-1236
The effects of Ru on the self-reducibility of Ru-doped Ni/MgAl2O4 catalysts, which do not need pre-reduction treatment with H2, were investigated in the steam reforming of methane (SRM). The Ru-promoted Ni/MgAl2O4 catalysts with various amounts of Ru (0–0.5 wt%) were prepared by stepwise impregnation and co-impregnation methods using
hydrotalcite-like MgAl2O4 support. For comparison, Ru/MgAl2O4 catalysts with the same amount of Ru were also prepared by the impregnation method. The catalysts were characterized by the
N2-sorption, XRD, H2-TPR, H2-chemisorption, and XPS methods. Ni/MgAl2O4 catalyst in the presence of even the trace amount of Ru (Ru content ≥0.05 wt%) showed higher conversion without pre-reduction
as compared to Ru/MgAl2O4 catalysts in SRM under the same conditions. The self-activation of Ru–Ni/MgAl2O4 catalysts is mainly attributed to the spillover of hydrogen, which is produced on Ru at first and then reduces NiO species
under reaction conditions. Besides, Ru doping makes the reduction of NiO easier. The stepwise impregnated Ru/Ni/MgAl2O4 catalyst produced superior performance as compared to co-impregnated Ru–Ni/MgAl2O4 catalyst for SRM. 相似文献
937.
Jong-il Choi Yong Jae Chung Dai Ill Kang Kyu Shik Lee Ju-Woon Lee 《Radiation Physics and Chemistry》2012,81(8):1051-1054
Fumigants, including methyl bromide and ethylene oxide, are generally used for the preservation of the Korean cultural heritage, especially paper products like letters and books. However, the use of fumigants is banned because of their harmful effects on humans and the environment. Gamma irradiation is being considered as an alternative for the sterilization of insects and fungi in organic products. Therefore, the purpose of this study was to investigate the sterilization effects of radiation and its effect on the mechanical properties of the Korean traditional paper—Hanji. Treatment doses of 9 kGy and 8 kGy of gamma irradiation inactivated 5 log units of Aspergillus niger and Bacillus cereus spores inoculated on Hanji, respectively. The gamma irradiations up to an absorbed dose of 50 kGy resulted in no significant changes in the tensile strength, bursting strength, and appearance of Hanji. These results confirmed that radiation treatment disinfects the Korean traditional paper efficiently without changing its properties and that this treatment could be used to prevent the damage of Korean ancient archives by molds and fungi. 相似文献
938.
The effects of antimony (Sb) doping on solution‐processed indium oxide (InOx) thin film transistors (TFTs) were examined. The Sb‐doped InSbO TFT exhibited a high mobility, low gate swing, threshold voltage, and high ION/OFF ratio of 4.6 cm2/V s, 0.29 V/decade, 1.9 V, and 3 × 107, respectively. The gate bias and photobias stability of the InSbO TFTs were also improved by Sb doping compared to those of InOx TFTs. This improvement was attributed to the reduction of oxygen‐related defects and/or the existence of the lone‐pair s‐electron of Sb3+ in amorphous InSbO films. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
939.
Previously, plasma‐enhanced dry etching has been used to generate three‐dimensional GaAs semiconductor structures, however, dry etching induces surface damages that degrade optical properties. Here, we demonstrate the fabrication method forming various types of GaAs microstructures through the combination etching process using the wet‐chemical solution. In this method, a gold (Au)‐pattern is employed as an etching mask to facilitate not only the typical wet etching but also the metal‐assisted chemical etching (MacEtch). High‐aspect‐ratio, tapered GaAs micropillars are produced by using [HF]:[H2O2]:[EtOH] as an etching solution, and their taper angle can be tuned by changing the molar ratio of the etching solution. In addition, GaAs microholes are formed when UV light is illuminated during the etching process. Since the wet etching process is free of the surface damage compared to the dry etching process, the GaAs microstructures demonstrated to be well formed here are promising for the applications of III–V optoelectronic devices such as solar cells, laser diodes, and photonic crystal devices. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
940.
Jae Hoon Lim Sung-Yu Hong Soo Jung Kang Hyun-Ju Doh Jaewoo Song Jong Rak Choi Kwang-Hoe Chung Jinsub Choi 《Electrochemistry communications》2009,11(11):2141-2144
Simple and cost-effective process for the fabrication of a nanodot strip which can electrochemically determine blood coagulation time was described in detail. We observed that the beginning of blood coagulation on the nanodot surface gives rise to increase in resistance against current flow, leading to suddenly increase in potential when constant current is applied between the nanodot electrodes. Interestingly, such dramatic increase in potential was not observed in the plain surface and non-controlled rough surface. 相似文献