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991.
With the aid of a synthesis design system, we searched for common intermediates in routes to sets of target molecules. Finding such common intermediates will be a great help in constructing cost-effective synthetic routes. We tried to look for new common intermediates with 24 investigational or commercially produced antidepressants as target molecules. Most of the common intermediates were usually found to lead to more than two targets. 相似文献
992.
Net absorptive CIDEP generation has been demonstrated on singlet molecular oxygen and 4-oxo-2,2,6,6-tetramethyl-1-piperidinyloxyl (OTEMPO) radical system in benzene. CIDEP generation was reasonably explained in terms of the radical-triplet pair mechanism of triplet molecular oxygen-OTEMPO pair with doublet precursor. Several excited molecule-OTEMPO systems have been investigated if this CIDEP generation contributes to their CIDEP spectra. Surprisingly strong CIDEP was produced even in the presence of trace amount of dissolved oxygen, which suggests the importance of complete degassing for CIDEP studies in general systems. 相似文献
993.
We compare Brouwer's bar theorem and Spector's bar recursion for the lowest type in the context of constructive reverse mathematics. To this end, we reformulate bar recursion as a logical principle stating the existence of a bar recursor for every function which serves as the stopping condition of bar recursion. We then show that the decidable bar induction is equivalent to the existence of a bar recursor for every continuous function from to with a continuous modulus. We also introduce fan recursion, the bar recursion for binary trees, and show that the decidable fan theorem is equivalent to the existence of a fan recursor for every continuous function from to with a continuous modulus. The equivalence for bar induction holds over the extensional version of intuitionistic arithmetic in all finite types augmented with the characteristic principles of Gödel's Dialectica interpretation. On the other hand, we show the equivalence for fan theorem without using such extra principles. 相似文献
994.
Junko Kimura Hiroshi Yamada Takehiko Yajima Takeshi Fukushima 《Journal of luminescence》2009,129(11):1362-1365
The chelating ligand, 2,4-[bis-(2,4-dihydroxybenzylidene)]-dihydrazinoquinazoline (DBHQ) can form a fluorescence complex with Ga3+ ions. The fluorescence intensity of the obtained DBHQ–Ga3+ complex increases in the presence of some phosphorylated compounds. The addition of phosphorylated serine and tyrosine, pyridoxal-5′-phosphate (PLP), and glucose-6-phosphate (G6P) leads to an increase in the fluorescence quantum yield (φ) of the complex by 1.38–1.59 times, while the addition of serine, tyrosine, pyridoxal, and glucose leads to a small increase in φ (1.02–1.04). This is the first report on the fluorescence enhancement effect of phosphorylated compounds on a Ga3+ ion complex. 相似文献
995.
So Hatakeyama Shinsuke Kunimura Nobuharu Sasaki Takashi Yamamoto Jun Kawai 《Analytical sciences》2008,24(7):847-850
A portable instrument for two-dimensional X-ray fluorescence imaging was assembled with an X-ray source using a pyroelectric crystal, which was driven by a 9-V dry battery, a Si-PIN detector, a slit, and pulse motors. Line scanning for a mug and a knife-edge-scan of an iron sheet were carried out using this spectrometer. The sensitivity of the spectrometer was sufficient for elemental analysis of a mug using a 1 mm(2) slit, and several elements, such as Co, Ni, Zn, Pb and Zr, were detected. The estimated spatial resolution using a 0.8-mm pinhole was 3.5 mm. 相似文献
996.
997.
Tomoaki Ohmura Erisa Harada Toshimichi Fujiwara Gota Kawai Kimitsuna Watanabe Hideo Akutsu 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,131(2):367-372
In the spectrum of uniformly15N-labeled cytochromec3, the relative linewidths of the doublet peaks of the15N-coupled imido proton of the coordinated imidazole group were reversed on oxidation. This inversion was explained by the interference relaxation process between the electron–proton dipolar and15N–1H dipolar interactions. The inversion can be used to assign the imido protons of the coordinated imidazole groups in heme proteins. 相似文献
998.
Syusuke Oosaki Yoshikazu Kawai Setsuko Yajima Keiichi Kimura 《Analytical sciences》2004,20(8):1165-1169
Polymer-supported liquid-crystal membranes have been designed for neutral-carrier-type potassium ion-selective electrodes, aiming for practical applications of high-performance liquid-crystalline membrane ion sensors. Two types of polymer-supported liquid-crystal membranes were tested for their usefulness; one is microporous poly(tetra fluoroethylene) (PTFE) membranes impregnated by thermotropic liquid-crystalline compounds, and another is poly(methyl methacrylate) (PMMA) membrane dispersing the same liquid-crystalline compounds. Both of the polymer-supported liquid-crystal membranes containing a liquid-crystalline benzo-15-crown-5 neutral carrier as well as a lipophilic anion excluder work well as ion-sensing membranes for potassium ion-selective electrodes, the ion selectivities of which can be switched by the measurement temperatures. Specifically, PTFE-impregnated liquid-crystal membranes are better than the PMMA-dispersed ones in the sensitivity and selectivity of the resulting ion electrodes. A potassium ion assay in blood sera has proved that neutral-carrier-type ion-selective electrodes based on the polymer-supported liquid-crystal membranes are reliable for practical uses. 相似文献
999.
Terasawa reported strong X-ray emission from charged-up insulators, and proposed an X-ray production device only using the electrification. We constructed a similar device and studied the conditions of X-ray emission. It was shown that X-rays could be produced without supplying electrons from a filament. 相似文献
1000.
Stereospecific synthesis of a family of novel (E)‐2‐aryl‐1‐silylalka‐1,4‐dienes or (E)‐4‐aryl‐5‐silylpenta‐1,2,4‐trienes via a cross‐coupling of (Z)‐silyl(stannyl)ethenes with allyl halides or propargyl bromide is described. In the reaction with allyl bromide, either a Pd(dba)2? CuI combination (dba, dibenzylideneacetone) in DMF or copper(I) iodide in DMSO–THF readily catalyzes or mediates the coupling reaction of (Z)‐silyl(stannyl)ethenes at room temperature, producing novel vinylsilanes bearing an allyl group β to silicon with cis ‐disposition in good yields. Allyl chlorides as halides can be used in the CuI‐mediated reaction. CuI alone much more effectively mediates the cross‐coupling reaction with propargyl bromide in DMSO–THF at room temperature compared with a Pd(dba)2? CuI combination catalysis in DMF, providing novel stereodefined vinylsilanes bearing an allenyl group β to silicon with cis ‐disposition in good yields. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献