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991.
设计合成了一种新型的基于5-芳基-2-巯基噁二唑辅助配体的双核环金属铂配合物(dfppy)2Pt2(C8OXT)2,其中dfppy为2-(4,6-二氟苯基)吡啶,C8OXT为5-苯基-2-巯基-1,3,4-噁二唑桥连配体.系统研究了该双核铂配合物(dfppy)2Pt2(C8OXT)2的热稳定性、光物理、电化学及电致发光性能.以(dfppy)2Pt2(C8OXT)2作为客体掺杂到聚合物主体材料中制备了单发光层聚合物电致发光器件.器件展现了饱和的红光发射,其最大发射峰为620nm.当配合物掺杂浓度为8wt%时,器件性能达到最好.其最高外量子效率为8.4%,最高电流效率为4.2cd/A,最大亮度为3228cd/m2.本研究表明,以5-苯基-2-巯基-1,3,4-噁二唑作为桥连配体的双核铂配合物在聚合物器件中能够实现高效红光发射. 相似文献
992.
研究了茜素红与阿魏酸哌嗪的显色反应,建立了阿魏酸哌嗪含量测定的分光光度法.在水溶剂中阿魏酸哌嗪与茜素红发生荷移反应生成紫红色的复合物,其最大吸收波长为524nm,表观摩尔吸光系数为1.86×103 L·mol-1·cm-1.阿魏酸哌嗪的浓度在1.6048.0mg·L-1范围内与体系的吸光度呈良好的线性关系,其线性回归方程为A=0.021 07+0.003 93c(mg·L-1,R=0.999 2),方法的检出限为1.19mg·L-1.将此新方法应用于阿魏酸哌嗪片中阿魏酸哌嗪含量的测定,回收率在97.5%48.0mg·L-1范围内与体系的吸光度呈良好的线性关系,其线性回归方程为A=0.021 07+0.003 93c(mg·L-1,R=0.999 2),方法的检出限为1.19mg·L-1.将此新方法应用于阿魏酸哌嗪片中阿魏酸哌嗪含量的测定,回收率在97.5%100.9%之间. 相似文献
993.
Ying San Liou 《Journal of Raman spectroscopy : JRS》2015,46(1):133-140
Archaeological finds of Neolithic to Iron Age pottery show clay potsherds characterized by red cord‐markings. The items date back from 5500 to 1500 B.P. To better understand temporal changes in the provenance of raw‐material sources, and the nature of materials used in the red colorant and ceramic bodies, micro‐Raman spectroscopy, X‐ray diffraction analysis (XRD), and micro X‐ray florescence spectroscopy (μXRF) were applied to 29 red‐coated potsherd samples found at twelve archaeological sites across Taiwan. The techniques identified the chemical and mineralogical composition of the red coatings and ceramic bodies as well as the production methods of ancient potters. Eighteen mineral phases were identified from the Raman spectra, including hematite, α‐quartz, and anatase. Feldspar, rutile, pyroxenes, calcite, gypsum, amorphous carbon, and graphite were also detected. XRD measurements, and μXRF analyses were used as complementary techniques to obtain mineral and chemical compositions. Hematite, anatase, calcite, plagioclase feldspar, and illite were present in potsherds, suggesting pottery produced from illitic clays fired at less than 850 °C under oxidizing conditions. Results further suggest that raw materials were sourced from or near local volcanic rock areas, and more broadly from metamorphic or sedimentary rocks and clays. Chemically, raw materials used for red coatings are different to those of the ceramic bodies. Objects from most sites used the same raw material sources; however, some sites contain objects made from changing sources over time. Pot coatings exhibit polygonal cracks, and loosened cementation strongly suggesting that finely processed moist clays were fired to a biscuit form with no second stage firing process. The non‐destructive Raman experiments identified and characterized mineral phases, which helped understand manufacturing techniques. Overall the multi‐technique approach gave extensive information on the finds, helping to differentiate raw material sources and production technologies. This approach is an important and effective method for investigating archaeological finds. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
994.
Measurements of optical limiting response in disperse red 1 dye doped into ethylene propylene diene polymethylene polymer (EPDM) are reported using 532 nm wavelength, 10 ns pulses from a frequency-doubled Nd-YAG laser. The optical limiting behavior of the dye doped polymer was studied by transmission measurement technique at various concentrations. The results reveal that the optical limiting efficiency is dependent on concentration. 相似文献
995.
996.
997.
Time-resolved area normalized emission spectroscopy (TRANES) is a new method for the analysis of fluorescence of dyes in complex
chemical and biological systems (A S R Koti, M M G Krishna and N Periasamy, 2001,J. Phys. Chem.
105, 1767). The model-free method extends the power of time-resolved emission spectroscopy (TRES) analysis and removes the ambiguity
in the interpretation when the emission spectrum is time-dependent. Observation of an isoemissive point in TRANES analysis
of fluorescence is an unambiguous indication for the presence of two emissive species in the sample. The isoemissive point
occurs at a wavelength where the ratio of the radiative rates of the two species is equal to the ratio of their total radiative
rates. The polarity-sensitive nile red dye shows time-dependent emission spectra in the organized bilayer assemblies of TX
micelle and bilayer egg-phosphotidylcholine (egg-PC) membrane. Time-dependent spectra in complex systems support many important
models (solvation model and heterogeneity in the ground and/or excited state). TRANES analysis shows that the fluorescence
emission of nile red in TX micelle and egg-PC membrane is due to two emissive species solubilized in different sites. 相似文献
998.
在强光一号脉冲加速器上进行了国内首次的实验室软X光辐射三种材料的喷射冲量研究。结果表明,在能量为(0.2~0.33)keV、平均脉宽为39ns左右的X光辐射下,对灰漆、白漆和硬铝,在能注量分别为(92~152)J/cm2、(115~136)J/cm2和(163~192)J/cm2时,它们的冲量耦合系数分别为(0.61~0.80)Pa·s/(J·cm-2)、(0.58~0.97)Pa·s/(J·cm-2)和(0.61~0.84)Pa·s/(J·cm-2)。 相似文献
999.
Cotton fabric was treated with dichlorodimethylsilane (DCDMS) solution by two methods. In the first method, the fabrics were
directly dipped into DCDMS solution for different time intervals and in the second method, the fabric was first subjected
to radiofrequency (RF) plasma treatment for different durations and optimized exposure power condition and then immersed in
DCDMS solution. The physical properties of cotton fabrics, treated with DCDMS in the presence/absence of air plasma have been
compared with those of the control fabrics. Changes in the surface morphology structure and composition were observed through
scanning electron microscopy and attenuated total reflectance-IR. The change in colour parameters of the fabric due to the
treatment was assessed by Dataflash 100 colour measurement spectrophotometer with colourtools QC 1.3 colour quality software.
The water repellent property of untreated and modified fabrics was studied using AATCC test method 39 (1971). The effectiveness
of the water repellent property was checked by washing the treated fabrics up to ten cycles.
Article presented at the International Conference on the Frontiers of Plasma Physics and Technology, 9–14 December 2002, Bangalore,
India. 相似文献
1000.