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11.
Eriko Ohshima Keiji KusabaSinji Onodera Masae Kikuchi 《Journal of Physics and Chemistry of Solids》2002,63(3):419-423
High-pressure phase transition of Ta2NiO6 with the trirutile-type structure was investigated from the viewpoint of crystal chemistry. A new quenchable high-pressure phase was found in the pressure range higher than 7 GPa and 900°C. The high-pressure phase has an orthorhombic cell (a=4.797(1) Å, b=5.153(2) Å and c=14.85(1) Å and space group; Abm2), and it is more dense by 9.6% than the trirutile-structured phase. Infrared spectra of the trirutile-type phase and the high-pressure phase show that Ni2+ ions in the high-pressure phase are still in octahedral sites. The crystal structure of the high-pressure phase is considered as a cation-ordering trifluorite-type structure, which can be stabilized by a crystal field effect of Ni2+ ions. 相似文献
12.
We designed and fabricated a fully automatic fast face recognition optical parallel correlator [E. Watanabe and K. Kodate:
Appl. Opt. 44 (2005) 5666] based on the VanderLugt principle. The implementation of an as-yet unattained ultra high-speed system was aided
by reconfiguring the system to make it suitable for easier parallel processing, as well as by composing a higher accuracy
correlation filter and high-speed ferroelectric liquid crystal-spatial light modulator (FLC-SLM). In running trial experiments
using this system (dubbed FARCO), we succeeded in acquiring remarkably low error rates of 1.3% for false match rate (FMR)
and 2.6% for false non-match rate (FNMR). Given the results of our experiments, the aim of this paper is to examine methods
of designing correlation filters and arranging database image arrays for even faster parallel correlation, underlining the
issues of calculation technique, quantization bit rate, pixel size and shift from optical axis. The correlation filter has
proved its excellent performance and higher precision than classical correlation and joint transform correlator (JTC). Moreover,
arrangement of multi-object reference images leads to 10-channel correlation signals, as sharply marked as those of a single
channel. This experiment result demonstrates great potential for achieving the process speed of 10000 face/s. 相似文献
13.
Midori Nishide Yutaka Yoshikawa Eriko U Yoshikawa Kinuyo Matsumoto Hiromu Sakurai Naemi M Kajiwara 《Chemical & pharmaceutical bulletin》2008,56(8):1181-1183
We prepared 4 new Zn(II) complexes with Zn(O4), Zn(N(2)O(2)), and Zn(S2O2) coordination modes and evaluated their insulinomimetic activities in an in vitro study. The insulinomimetic activities of bis(pyrrole-2-carboxylato)zinc (Zn(pc)2), bis(alpha-furonic acidato)zinc (Zn(fa)2), bis(thiophene-2-carboxylato)zinc (Zn(tc)2), and bis(thiophene-2-acetato)zinc (Zn(ta)2) complexes were found to be higher than that of zinc sulfate (ZnSO4). Zn(ta)2 showed the highest insulinomimetic activity among the Zn(II) complexes because of its high lipophilicity. 相似文献
14.
15.
Mitsushiro Nomura Shigemi Kondo Eriko Suzuki Glenn V. Alea Chikako Fujita-Takayama Masatsugu Kajitani 《Journal of organometallic chemistry》2010,695(21):2366-2895
Eight new sulfur-rich [CpCo(dithiolene)] complexes were synthesized from [Zn(dmit)2]2− as a starting material. The structures, electrochemical behavior and electronic absorption spectra of the sulfur-rich [CpCo(S2C2S2Y)] complexes could be compared with the early data of analogous Ni complexes. [CpCo(pddt)] (Y = -(CH2)3-), [CpCo(dpdt)] (Y = -CH2C(CH2)CH2-), [CpCo(bddt)] (Y = -(CH2)4-), [CpCo(dtdt)] (Y = -CH2SCH2-) and [CpCo(poddt)] (Y = -CH2C(O)CH2-) crystallized in all isostructural with the corresponding paramagnetic [CpNi(dithiolene)] complexes, but [CpCo(dmid)] (Y = CO), [CpCo(dddt)] (Y = -(CH2)2-) and [CpCo(F2pddt)] (Y = -CH2CF2CH2-) crystallized in non-isostructural with them. These molecules are associated with intermolecular short S?S contacts in the crystals. [CpCo(F2pddt)] did not show any remarkable S?S contacts but indicated interesting fluorine segregation and Cp?Cp face-to-face interactions. Redox potentials of [CpCo(dithiolene)] complexes were obtained with the cyclic voltammetry measurements and dimerized by electrochemical oxidations. Electronic absorption spectra of [CpCo(dithiolene)] complexes showed visible absorption in the range of 585-701 nm as lowest energy wavelengths (? = 9800-11,800 M−1 cm−1) in solutions, and they were higher energy than those of [CpNi(dithiolene)] complexes (near-IR). 相似文献
16.
17.
Seiji Yamaguchi Eriko Hamade Hajime Yokoyama Yoshiro Hirai Shunsaku Shiotani 《Journal of heterocyclic chemistry》2002,39(2):335-339
Birch reduction of four furopyridines 1a‐d effected the characteristic cleavage of the furan ring, giving ethnylpyridinols 2a‐d , vinylpyridinols 3b,d , and ethylpyridinols 4a‐d , and the reduction of the furan ring, giving dihydrofuropyridine 5c,d. 相似文献
18.
Watanabe M Yamamoto T Yamamoto A Obana E Niiyama K Hada T Ooie T Kataoka M Hori T Houchi H Shinohara Y 《Applied biochemistry and biotechnology》2011,165(2):538-547
The thermogenic function of brown adipose tissue (BAT) is known to be markedly elevated when animals are exposed to the cold, and intensive studies have been carried out to understand the molecular basis enabling effective thermogenesis in cold-exposed animals. In this study, we used microarray analysis to examine the effects of cold exposure of animals on their gene expression profiles in white adipose tissue (WAT), which seems to function as a counterpart tissue of BAT. The results indicate that the effects of cold exposure on the gene expression profiles of WAT were much more moderate than the effects on those of BAT. Possible reasons for the different responses of BAT and WAT to cold exposure are discussed. 相似文献
19.
Kodama K Sekine E Hirose T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(41):11527-11534
Ternary organic crystals consisting of an L-tartaric acid-derived dicarboxylic acid, a commercially available achiral diamine, and a chiral secondary alcohol have been developed and characterized by X-ray crystallography. 1D, 2D, and 3D hydrogen-bonded supramolecular networks were constructed, depending on the structure of the diamine used. Benzylic and aliphatic secondary alcohols were enantioselectively incorporated into the crystal and were successfully enantioseparated with up to 86 and 79% enantiomeric excess (ee), respectively. Selective incorporation of one enantiomer of 2-butanol, which is a small chiral aliphatic alcohol, was achieved by the cooperative effects of hydrogen bonds, CH···π interactions, and van der Waals interactions between the guest and host molecules, with the aid of two water molecules. The high host potential of the binary supramolecular system is mainly attributed to the skewed conformation of two rigid aromatic groups of tartaric acid derivatives, which prevents dense packing of the molecules and enhances the formation of multicomponent inclusion crystals. 相似文献
20.
Kamisaki H Nanjo T Tsukano C Takemoto Y 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(2):626-633
The formal synthesis of hemiterpene spirooxindole alkaloids elacomine (1) and isoelacomine (2) is described. Heck reaction of protected iodoanilines with 5,6-dihydro-2H-pyran-2-one or six-membered unsaturated lactams was investigated. The coupling product was readily converted to a carbamoyl chloride with an incorporated diene unit. The spiro(pyrrolidine-3,3'-oxindole) skeleton, which corresponds to the carbon skeleton of 1 and 2, was efficiently constructed from this intermediate by using a domino palladium-catalyzed Heck reaction and bismuth-catalyzed hydroamination. An isolated byproduct of the reaction could also be converted to the spirooxindole skeleton. 相似文献