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51.
A glass capillary ultramicroelectrode (tip diameter approximately 1.2 microm) having an electrokinetic sampling ability is described. It is composed of a pulled glass capillary filled with an inner solution and three internal electrodes (Pt working and counter electrodes and an Ag/AgCl reference electrode). The voltammetric response of the capillary electrode is based on electrokinetic transport of analyte ions from the sample solution into the inner solution across the conical tip. It was found that the electrophoretic migration of analytes at the conical tip is faster than electroosmotic flow, enabling electrokinetic transport of analyte ions into the inner solution of the electrode. By using [Fe(CN)6]4- and (ferrocenylmethyl)trimethylammonium (FcTMA+) ions as model analytes, differential pulse voltammetric responses of the capillary electrode were investigated in terms of tip diameter of the capillary, sampling voltage, sampling time, detection limit and selectivity. The magnitude of the response depends on the size and charge of analyte ions. With a capillary electrode having a approximately 1.2-microm tip diameter, which minimizes non-selective diffusional entry of analytes, the response after 1 h sampling at +1.7 V is linearly related to [Fe(CN)6]4- concentration in the range of 0.50-5.0 mM with the detection limit of 30 microM. Application of a potential of the same sign as that of the analyte ion forces the analyte to move out from the electrode to the solution, enabling reuse of the same capillary electrode. The charge-selective detection of analytes with the capillary electrode is demonstrated for [Fe(CN)6]4- in the presence of FcTMA+. 相似文献
52.
Nara TY Togashi H Sekikawa C Kawakami M Yaginuma N Sakaguchi K Mizukami F Tsunoda T 《Colloids and surfaces. B, Biointerfaces》2009,68(1):68-73
Zeolites are microporous crystalline aluminosilicates with a highly ordered structure. Using zeolite beta as an adsorbent, denatured/reduced hen egg lysozyme was refolded to the active form at high concentrations. The denatured/reduced lysozyme was adsorbed onto the zeolite and the protein was refolded by desorbing it into refolding buffer, consisting of redox reagents, guanidine hydrochloride, polyethylene glycol, and L-arginine. This zeolite refolding method could be highly effective for various kinds of proteins, refolding them with high efficiency even when they contain disulfide bonds. 相似文献
53.
Woochul Lee Nara Cho Jongchul Kwon Prof. Dr. Jaejung Ko Prof. Dr. Jong‐In Hong 《化学:亚洲杂志》2012,7(2):343-350
We have synthesized and characterized four organic dyes ( 9 , 10 , H1 , H2 ) based on a 3,6‐disubstituted carbazole donor as sensitizers in dye‐sensitized solar cells. These dyes have high molar extinction coefficients and energy levels suitable for electron transfer from an electrolyte to nanocrystalline TiO2 particles. Under standard air mass 1.5 global (AM 1.5 G) solar irradiation, a device using dye H4 exhibits a short‐circuit current density (Jsc) of 13.7 mA cm?2, an open‐circuit voltage (Voc) of 0.68 V, a fill factor (FF) of 0.70, and a calculated efficiency of 6.52 %. This performance is comparable to that of a reference cell based on N719 (7.30 %) under the same conditions. After 1000 hours of visible‐light soaking at 60 °C, the overall efficiency remained at 95 % of the initial value. 相似文献
54.
The automation of SDS-PAGE required substantial investment. To lower this barrier, we devised a cost-effective, simple, and general method where samples are loaded on SDS-PAGE gels held by a newly devised "Gel Adaptor" on a general automated liquid handler. In this method, the liquid handler loads samples on the SDS-PAGE gels held at an angle of 80 degrees on the Gel Adaptor so that the samples can be vertically loaded on the narrow paths of the wells of the slanted gels. This method allows the automated liquid handler to load 144 samples on SDS-PAGE gels in approximately 10 min, greatly reducing the time and cost for high-throughput SDS-PAGE analyses. 相似文献
55.
Mitsuhiro Kawazu Masatoshi Nara Toshifumi Tsujino 《Journal of Sol-Gel Science and Technology》2004,31(1-3)
TiO2 nano particles with photo catalytic property were mixed with silica alkoxides solution with HAuCl4/4H2O. STS02 (purchased from Ishihara Sangyo Kaisha, Ltd.) was used as TiO2 nano particles. The average size of TiO2 nano particles was 7 nm in diameter. The gel film coated on glass substrate was heated and then HAuCl4/4H2O was thermally reduced at 390 degree. The coated silica gel film doped with HAuCl4/4H2O and TiO2 nano particles was turned into light blue from colorless gel film after heat treatment. The optical absorption spectrum showed the absorption peak of the film heated at 390 degree shifted to at about 650 nm compare to SiO2 film doped with Au nano particles without TiO2 nano particles that had absorption peak at 542 nm. On the other hand, the film formed from coating solution incorporated TiAA (titanium tetraisopropoxide chelated by acetyl acetone) as TiO2 source instead of TiO2 nano particles had absorption peak at 550 nm. That means there was no effect on formation of Au nano particles when TiAA was incorporated. The average size of the particles was found to be about 23 nm in diameter by TEM observation. Furthermore EDX (Energy Dispersive X-ray Fluorescence Spectrometer) analysis of nano particles in the film indicated that Au-TiO2 nano hybrid particles were formed. Simulation results also supported that the size in diameter of Au nano particles had little influence on the absorption coefficient of the silica film doped with Au nano particles. 相似文献
56.
Proton collective flows in heavy-ion collisions from AGS ((2–11) A GeV) to SPS ((40,158) A GeV) energies are investigated
in a nonequilibrium transport model with nuclear mean-field (MF). Sideward (p
x), directedv
1, and ellipticv
2 flows are systematically studied with different assumptions on the nuclear equation of state (EoS). We find that momentum
dependence in the nuclear MF is important for understanding the proton collective flows at AGS and SPS energies. Calculated
results with momentum-dependent MF qualitatively reproduce the experimental data of proton sideward, directed, and elliptic
flows in an incident energy range of (2–158) A GeV
This talk is based on ref. [1] 相似文献
57.
Electrochemical impedance spectroscopy has been widely used to understand the chemistry and physics of battery systems. This review covers electrochemical impedance spectroscopy used for the interpretation of impedance data of lithium-ion batteries (LIBs) from advanced equivalent circuit models to the mathematical model, which is developed by John Newman. In addition, as a method to realize an energy-sustainable society using diagnostics based on the combination of LIBs and electrochemical impedance spectroscopy, on-board diagnostics of battery packs are achieved based on an input signal generated by a power controller in a battery management system instead of the conventionally used frequency response analyzer. The diagnostic system is applicable to energy management systems which are installed in homes, buildings, and communities, accumulating the impedance data on state of health of LIBs. Finally, a future possibility regarding the diagnostics of battery packs coupled with the machine learning of impedance data is introduced. 相似文献
58.
Nishihara Y Nara K Nishide Y Osakada K 《Dalton transactions (Cambridge, England : 2003)》2004,(9):1366-1375
Ar-B(OH)2 (1a: Ar = C6H4OMe-4, 1b: Ar = C6H3Me2-2,6) react immediately with Rh(OC6H4Me-4)(PMe3)3 (2) in 5 : 1 molar ratio at room temperature to generate [Rh(PMe3)4]+[B5O6Ar4]- (3a: Ar = C6H4OMe-4, 3b: Ar = C6H3Me2-2,6). p-Cresol (92%/Rh), anisole (80%/Rh) and H2O (364%/Rh) are formed from 1a and 2. The reaction of 1a with 2 for 24 h produces [Rh(PMe3)4]+[B5O6(OH)4]- (4) as a yellow solid. This is attributed to hydrolytic dearylation of once formed 3a because the direct reaction of 3a with excess H2O forms 4. An equimolar reaction of 2 with phenylboroxine (PhBO)3 causes transfer of the 4-methylphenoxo ligand from rhodium to boron to produce [Rh(PMe3)4]+[B3O3Ph3(OC6H4Me-4)]- (5). Arylboronic acids 1a and 1b react with Rh(OC6H4Me-4)(PR3)3 (6: R = Et, 8: R = Ph) and with Rh(OC6H4Me-4)(cod)(PR3) (11: R = iPr, 12: R = Ph) to form [Rh(PR3)4]+[B5O6Ar4]- (7a: R = Et, Ar = C6H4OMe-4, 7b: R = Et, Ar = C6H3Me2-2,6, 9a: R = Ph, Ar = C6H3Me2-2,6) and [Rh(cod)(PR3)(L)]+[B5O6Ar4]- (13b: R = iPr, L = acetone, Ar = C6H3Me2-2,6, 14a: R = Ph, L = PPh3, Ar = C6H4OMe-4, 14b: R = Ph, L = PPh3, Ar = C6H3Me2-2,6), respectively. Hydrolysis of 14a yields [Rh(cod)(PPh3)2]+[B5O6(OH)4]- (15) quantitatively. 相似文献
59.
Carlos L. P. Carone Geraldo L. Crossetti Nara R. S. Basso Álvaro G. O. Moraes João H. Z. dos Santos Rubens Bisatto Griselda B. Galland 《Journal of polymer science. Part A, Polymer chemistry》2007,45(22):5199-5208
The catalyst DADNi(NCS)2 (DAD = (ArN?C(Me)? C(Me)?ArN); Ar = 2,6‐C6H3), activated by methylaluminoxane, was tested in ethylene polymerization at temperatures above 25 °C and variable Al/Ni ratio. The system was shown to be active even at 80 °C and when supported on silica. However, catalyst activity decreased. The catalyst system was also tested in ethylene and 10‐undecen‐1‐ol copolymerization at different ethylene pressures. The best activities were obtained at low polar monomer concentration (0.017 mol/L), using triisopropylaluminum (Al‐i‐Pr3) to protect the polar monomer. The incorporation of the comonomer increased with the increase of polar monomer concentration. According to 13C NMR analyses, all the resulting polyethylenes were highly branched and the polar monomer incorporation decreased as ethylene pressure increased. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5199–5208, 2007 相似文献
60.
We have theoretically studied the adsorption of a thiophenethiolate (C4H3S-S) molecule on the Au(1 1 1) surface by first-principles calculations. It is found that the bridge site is the most stable adsorption site with the adsorption energy of 1.02 eV. In the optimized adsorption geometry, the bond between the head S atom and the connected C atom in the tail thiophene molecule is tilted by 57.2° from the surface normal. In addition, the adsorption of thiophenethiolate induces large relaxations of the surface Au atoms around it. Furthermore, weak interactions between the S atom in the tail thiophene ring and the Au atoms also contribute to the adsorption on the Au surface. 相似文献