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51.
The adsorption of oxygen on a polycrystalline zirconium surface at room temperature has been studied by metastable de-excitation spectroscopy (MDS) in conjunction with UPS and AES. From the analysis of the measured spectra, we have shown the following. (1) At the initial stage of oxygen adsorption (exposure <1.2 L), the surface density of states (SDOS) of zirconium changes little at around the Fermi level (EF), while it decreases appreciably at 1–2 eV below EF (EB=1–2 eV) by oxygen adsorption. (2) The SDOS at EB=0–2 eV decreases with increasing oxygen exposure at >1.2 L and disappears at >8 L. (3) The oxygen 2p states (EB=5–8 eV) are localized at the subsurface region at oxygen exposure 0–2 L. (4) The ZrO2 phase appears at the outermost zirconium surface at around 2 L, then grows with increasing exposure, and finally dominates at >8 L. It is suggested that two different phases (ZrO2 phase and that in which oxygen occupies subsurface sites) coexist at the outermost surface at 2–8 L. 相似文献
52.
DENG Ju-Zhi CHEN Rong SEKIGUCHI Tetsuhiro BABA Yuji HIRAO Norie HONDA Mitsunori 《中国物理C(英文版)》2008,32(9)
Thin silicon Phthalocyanine dichloride films on HOPG were prepared and the sample was heated in the vacuum with laser.The thickness of the thin sample on HOPG was checked by X-ray photoemission spectroscopy.The orientation of the molecules in respect to the substrate plane Was investigated by measuring the silicon K-edge near edge X-ray absorption fine structure(NEXAFS).In the NEXAFS spectra of the thin sample,two clear peaks which were assigned to 1s→σ*Si-N and 1s→σ*Si-C1 appeared around 1847.2 eV and 1843.1 eV respectively.The intensities of the resonance peaks showed strong polarization dependence.A quantitative analysis of the polarization dependence revealed that the Si-N bond tended to lie down while the Si-C1 bond was out of the molecular plane. 相似文献
53.
Mitsunori Asada Takao Fujimori Kenta Fujii Ryo Kanzaki Yasuhiro Umebayashi Shin‐ichi Ishiguro 《Journal of Raman spectroscopy : JRS》2007,38(4):417-426
The solvation structure of magnesium, zinc(II), and alkaline earth metal ions in N,N‐dimethylformamide (DMF) and N,N‐dimethylacetamide (DMA), and their mixtures has been studied by means of Raman spectroscopy and DFT calculations. The solvation number is revealed to be 6, 7, 8, and 8 for Mg2+, Ca2+, Sr2+, and Ba2+, respectively, in both DMF and DMA. The δ (O C N) vibration of DMF shifts to a higher wavenumber upon binding to the metal ions and the shift Δν(= νbound − νfree) becomes larger, when the ionic radius of the metal ion becomes smaller. The ν (N CH3) vibration of DMA also shifts to a higher wavenumber upon binding to the metal ions. However, the shift Δν saturates for small ions, as well as the transition‐metal (II) ions, implying that steric congestion among solvent molecules takes place in the coordination sphere. It is also indicated that, despite the magnesium ion having practically the same ionic radius as the zinc(II) ion of six‐coordination, their solvation numbers in DMA are significantly different. DFT calculations for these metalsolvate clusters of varying solvation numbers revealed that not only solvent–solvent interaction through space but also the bonding nature of the metal ion plays an essential role in the steric congestion. The individual solvation number and the Raman shift Δν in DMF–DMA mixtures indicate that steric congestion is significant for the magnesium ion, but not appreciable for calcium, strontium, and barium ions, despite the solvation number of these metal ions being large. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
54.
Masahito Segi Aojia Zhou Mitsunori Honda 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):1045-1049
Abstract The [4, 2] cycloadducts of selenoaldehydes and anthracene regenerate selenoaldehydes in situ quantitatively under neutral conditions via thermal retro Diels–Alder reaction. The reactions of selenoaldehydes generated by this method with 2-silyloxy-1,3-butadiene, 2-methoxyfuran, and 5-ethoxyoxazoles are described. 相似文献
55.
Shinji Tanimori Ushio Inaba Yoshihiro Kato Haruna Ura Hiroaki Kashiwagi Takeshi Nishimura Mitsunori Kirihata 《Research on Chemical Intermediates》2014,40(6):2157-2164
This paper reports our recent results from synthesis of some useful heterocycles, for example oxazolidinones, indoles, and quinoxalinones, by transition metal-catalyzed cascade processes. The scope and limitations of these procedures and the reaction mechanism for formation of the heterocycles are also discussed. 相似文献
56.
Kiyoshi Toda Mitsunori Miyake Hisao Ohtake 《Applied biochemistry and biotechnology》1990,26(2):139-149
A new process of biological waste treatment was developed by use of microbial films grown on the liquid surface in a shallow flow reactor. The performance of this process was tested using a synthetic waste that contained acetic acid as a model organic pollutant. About 90% of acetic acid (10,000 mg/L-1) in the synthetic waste was removed by setting alpha tau: (alpha specific liquid surface area, cm-1, and tau: hydraulic liquid detention time, h) higher than 15 cm-1/h. It was necessary to maintain alpha large enough (more than 10 cm-1 in most cases) to satisfy oxygen demand for the biooxidation. The oxygen balance and TOC determinations showed that the acetic acid removed was completely oxidized with oxygen transferred through the liquid surface. This process would contribute to energy savings, since it requires no forced aeration for oxygen supply. 相似文献
57.
Daisuke BAI Mitsunori TOKUDA Taiki IKEMOTO Shingo SUGIMORI Shoki OKAMURA Yuka YAMADA Yuna TOMITA Yuki MORIKAWA Yasuhito TANAKA 《Physical Therapy Research》2021,24(1):24
Objectives: This study aimed to assess physical function such as lower limb function and Activities of Daily Living after surgery for proximal femoral fractures ( unstable medial femoral neck fracture and trochanteric fracture). Methods: This study enrolled 68 patients with proximal femoral fractures. Isometric knee extension strength (IKES), the Japanese Orthopedic Association (JOA) hip score, and the number of days required to develop straight leg raising, transfer, and T-caneassisted gait abilities to become independent were assessed. Patients were classified based on the types of proximal femoral fractures, namely unstable medial femoral neck fracture (bipolar hip arthroplasty [BHA] group), stable trochanteric fracture (S group), and unstable trochanteric fracture (US group). Results: IKES and the JOA hip score were significantly better in the BHA group than in the S and US groups. IKES and the JOA hip score were significantly worse in the US group than in the BHA and S groups. Both transfer and T-cane-assisted gait abilities of patients in the BHA and S groups were indifferent. However, all physical functions were significantly worse in the US group. Conclusions: Our study results suggested that physical therapists plan the different rehabilitation program for the patients with proximal femoral fractures who were classified into three types, namely unstable medial femoral neck fracture, stable trochanteric fracture, and unstable trochanteric fracture, instead of two types. 相似文献
58.
Mitsunori Honda Yusuke Taniguchi Tomohiro Hayashi Ko-Ki Kunimoto Masahito Segi Takahiro Yamaguchi 《Tetrahedron letters》2017,58(48):4554-4558
The synthesis of a novel class of 3-silyl substituted thiophenes possessing perfluoroalkyl groups on the silicon atom was investigated. The treatment of 3-bromothiophene with n-butyllithium followed by the reaction with halosilanes proceeded to afford the corresponding 3-silyl substituted thiophenes 1 in good yields. The chemical polymerization of the resulting 1 did not work well. However, the electropolymerization of 3-silylthiophenes 1a and 1b provided the corresponding polymers 5a and 5b with head-to-tail regioregularity. The cyclic voltammogram of the resulting polymers 5a and 5b indicated both n- and p-doping properties. 相似文献
59.
60.
Tomonori Mori Dr. Shuhei Higashibayashi Dr. Taiji Goto Mitsunori Kohno Yukiko Satouchi Kazuyuki Shinko Kengo Suzuki Shunya Suzuki Hiraku Tohmiya Kimiko Hashimoto Prof. Dr. Masaya Nakata Prof. Dr. 《化学:亚洲杂志》2008,3(6):984-1012
The five practical segments for the total synthesis of siomycin A, that is, the dehydropiperidine segment A ( 5 ), the pentapeptide segment B ( 3 ), the dihydroquinoline segment C ( 6 ), and the β‐phenylselenoalanine dipeptide segments D ( 7 ) and E ( 4 ), were synthesized. Segment A ( 5 ) was constructed by the coupling of the azomethine ylide and the chiral sulfinimine, followed by the stereoselective reduction of the six‐membered imine function. Segment B ( 3 ) was synthesized by the phenylselenylation of the β‐lactone, stereoselective vinylzinc addition to the chiral sulfinimine, and oxazoline–thioamide conversion. Segment C ( 6 ) was prepared by the one‐pot olefination of the tetrahydroquinoline N‐oxide using triflic anhydride and triethylamine, stereoselective reduction of the methyl ketone function, and regioselective Yb(OTf)3‐catalyzed epoxide opening by the amino group. Segments D ( 7 ) and E ( 4 ) were synthesized by coupling of the properly protected β‐phenylselenoalanines. 相似文献