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101.
Hiroaki Itoi Taehee Jang Shinji Kanehashi Takeshi Shimomura Kenji Ogino 《Tetrahedron letters》2017,58(36):3579-3582
A new macrocyclic AIE emitter composed of triarylamine backbone was successfully synthesized through convenient homocoupling procedure and easily purified by silica gel column chromatography, and recrystallization. The optical and electrochemical properties of the compound have been investigated. Intriguingly, the compound shows dual emission both 423 nm and 505 nm. This result implied that the violet emission was originated from an isolated component of the emitter, whereas the yellowish-green emission simultaneously exhibited AIE nature. The compound exhibits enough thermal stability and high glass transition temperature to be applied for organic devices. 相似文献
102.
Tomohiro Oikawa Tatsuya Urabe Shin-ichi Kawano Miho Tanaka 《Journal of solution chemistry》2011,40(6):1094-1107
Lanthanide nitrate (Ln(NO3)3) solutions were analyzed by electrospray ionization mass spectrometry (ESI-MS) to characterize the solution states of the
lanthanides. The following monomer species were observed: [Ln(OH)(H2O)
j
]2+, [Ln(OH)2(H2O)
k
]+, [Ln(NO3)(OH)(H2O)
l
]+ and [Ln(NO3)2(H2O)
m
]+ (j,k,l,m: numbers of adducted H2O). The peak intensity ratio of each Ln species was calculated from the peak intensity of the Ln species divided by the total
peak intensity of all the Ln species. The change in the relative peak intensities of [Ln(OH)(H2O)
j
]2+ and [Ln(OH)2(H2O)
k
]+ was consistent with changes in the hydration number of Ln (La to Tb: 9, Tb to Lu: 8). The behavior of the relative peak intensity
of [Ln(NO3)(OH)(H2O)
l
]+ against the atomic number of Ln was similar to those of the stability constants of the lanthanides and the nitrate group.
ESI-MS is expected to be a useful technique for examining lanthanide reactions in solution. 相似文献
103.
Prof. Satoshi Nakata Tatsuya Miyaji Taisuke Sato Miho Hoshikawa Dr. Yumihiko S. Ikura Prof. Shunsuke Izumi 《Chemphyschem》2012,13(18):4129-4133
The mode change of a simple autonomous motor depending on the nature of a monolayer on water is investigated. A camphor disk is floated on a molecular layer of N‐stearoyl‐p‐nitroaniline (C18ANA), which gives a surface‐pressure (π)–area per molecule (A) isotherm with a local maximum and a local minimum. The nature of the camphor motion changes depending on A, and in particular, reciprocating motion is observed at a lower A while cutting out its own trajectory of motion. The characteristic motion of a camphor disk depending on A is discussed in relation to the π–A isotherm of C18ANA and the influence of the molecular interaction between molecules on the driving force of motion. 相似文献
104.
Toyoshima M Hosoda K Hanamura M Okamoto K Kobayashi H Negishi T 《Journal of photochemistry and photobiology. B, Biology》2004,73(1-2):59-66
Numerous epidemiological investigations show that sunlight is carcinogenic to humans and that the use of sunscreen may be effective in decreasing the risk of skin cancer. The biological activity of a sunscreen is evaluated by its ability to protect human skin from erythema as represented by a Sun Protection Factor (SPF). We propose that the sunscreen's protective effect against sunlight-induced genotoxicity, including mutation, should also be taken into account. In this study we examined the protective ability of sunscreens against natural sunlight and UV-induced genotoxicity in Drosophila somatic cells. We prepared three kinds of sunscreen samples, each with an SPF value of 20, 40 or 60 and compared their protective activities with commercial sunscreens. When a sunscreen of SPF 20, 40 or 60 was pasted on the plastic cover of a petri dish in which Drosophila larvae were exposed to the sun or UV lamps, genotoxicity decreased as the SPF of the sunscreen increased, relative to levels of genotoxicity observed in samples without sunscreen. However, the protective abilities of sunscreens were unexpectedly not so different from each other. To reveal the relationship between the protective activity of sunscreen and the wavelength of light with which larvae were irradiated through the sunscreen, we measured the transmittance of light through the petri dish cover on which the sunscreen was pasted. Effective protection was demonstrated by removing components of light whose wavelengths were below 315 nm. We suggest, that the measurement of anti-genotoxic activity and the determination of the wavelengths of light transmitted through the sunscreen should be an alternative method for evaluating the effectiveness of a sunscreen. 相似文献
105.
Tomohito Kameda Toshiaki Yoshioka Miho Uchida Akitsugu Okuwaki 《Molecular Crystals and Liquid Crystals》2013,570(2):407-412
Abstract Three methods of synthesizing hydrotalcite(HT) have been developed using magnesium from seawater and dolomite(MgCa(CO3)2). In the first process, 1.0M Na2CO3solution was added to calcium ion free artificial seawater containing AlCl3 with an initial Mg/Al molar ratio of 2.0~3.7 until a pH of 10 was obtained. The solution was then continuously stirred for Ih at 60°C. CO3 2--HT was precipitated as a single phase, and the initial Mg/Al molar ratio, which each recovery of Mg2+and Al3+ from the solution was above 98%, was 2.0–2.3. In the second process, a Ca(OH)2 slurry was added to artificial seawater containing AlCl3 with an initial Mg/Al molar ratio of 1.0~5.0 until a pH of 10.5 was obtained, and then was stirred for Ih at 60°C. HT was also precipitated as a single phase with initial Mg/Al molar ratio 2.0~4.0. The initial Mg/Al molar ratio, which each recovery of Mg2+ and Al3+ from the solution was above 98%, was 2.2~3.3, but SO4 2- and Cl? were contained in the precipitated HT. When HT was produced using initial Mg/Al molar ratio of 3.0 at 25°C, SO4 2- and Cl?in the HT were ion-exchanged with CO3 2- in a 0.05M Na2CO3solution for 24h at 25°C, and SO4 2- and Cl? content of the HT were decreased to 0.5 and 0.05wt%, respectively. In the third process, dolomite calcined at 1000°C was added to an AlCl3 solution with an initial Mg/Al molar ratio of 1.0~2.0, and the solution was stirred for 1~4h at 25~90°C. HT was precipitated with the smallest amount of MgO and Mg(OH)2 when the initial Mg/Al molar ratio was 1.5 and the solution was stirred for 4h at 90°C. 相似文献
106.
Miho Yamauchi Shin'ichi Ishimaru Ryuichi Ikeda 《Molecular Crystals and Liquid Crystals》2013,570(2):315-320
Abstract Dynamic behavior of n-octylammonium ions intercalated into saponite was investigated by 2H and 1H solid NMR method. Obtained data indicate distributions in the rate of cationic axial reorientations characterized by the heterogeneity of charge distribution in the saponite layer plane. Above ca. 400 K, in-plane random reorientations of cations were observed as a new kind of motion in the 2-D ionic system. 相似文献
107.
Ohyama K Takemura M 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2008,84(1):17-23
We here describe in detail the characterization and molecular evolution of group II introns in the mitochondrial genome of the liverwort Marchantia polymorpha. We find that 18 introns of the 25 group II introns can be assigned by their similarities to six clusters, indicating an intra-genomic propagation of one ancestral intron each into the respective clusters in the liverwort mitochondrial genome. Interestingly, the intra-genomic propagation of some of these introns occurred only after the evolutionary separation of the bryophytes from the other clades of plants. Finally we report that the maturase-like sequences in the liverwort group II introns have further evolved by horizontal and independent transposition and substitution by analogous sequences from other fungal introns. 相似文献
108.
Miho C. Emoto Shingo Sato Hirotada G. Fujii 《Magnetic resonance in chemistry : MRC》2016,54(9):705-711
Theranostic probes provide both therapeutic and diagnostic imaging capabilities in one molecule and show significant promise for use in magnetic resonance imaging (MRI) examinations. The present study describes for the first time the synthesis and utility of nitroxide‐based contrast agents exhibiting a nonsteroidal anti‐inflammatory drug effect. The target theranostic probes were prepared by connecting the carboxyl group of ibuprofen or ketoprofen to the hydroxyl group of 3‐hydroxymethyl‐2,2,5,5‐tetramethylprrolidine‐1‐oxyl by a condensation reaction in the presence of dicyclohexylcarbodiimide and 4‐dimethylaminopyridine in dichloromethane. MRI of mouse heads after administration of either synthesized theranostic probe indicated that the probes enter the brain by passing through the blood–brain barrier (BBB), resulting in T1 contrast enhancement in mouse brain. This enhancement persisted for the duration of the half‐life of about 40 min, which is longer than that obtained by most of pyrrolidine nitroxide molecules. The therapeutic capacities of these theranostic probes were examined using a lipopolysaccharide (LPS)‐induced brain inflammation model. The production of nitric oxide, an inflammation marker in septic mouse brain induced by LPS, was remarkably inhibited by the addition of either synthesized probe, indicating that they also act as anti‐inflammatory drugs. The present results indicate that nitroxide‐based theranostic probes act as both BBB‐permeable redox‐sensitive contrast agents and as an anti‐inflammatory drug in septic mouse brain. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
109.
Minako Kitahara Miho Marui Noriyuki Oshimo Tomomi Saito Akio Sugamoto 《The European Physical Journal C - Particles and Fields》1998,4(4):661-667
The supersymmetric standard model contains a new -violating phase in the mass matrices for charginos and neutralinos, which could induce -odd anomalous couplings for the and vertices at the one-loop level. We study these couplings, paying attention to the model-parameter and dependencies. It is shown that the -odd form factors could have values of order , which are much larger than those predicted by the standard model. We also discuss the possibility of examining these form
factors in experiments.
Received: 6 October 1997 / Published online: 26 February 1998 相似文献
110.