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161.
D. Eilidh Sood Sue Champion Daniel M. Dawson Sonia Chabbra Bela E. Bode Andrew Sutherland Allan J. B. Watson 《Angewandte Chemie (International ed. in English)》2020,59(22):8460-8463
Deoxyfluorination is a primary method for the formation of C?F bonds. Bespoke reagents are commonly used because of issues associated with the low reactivity of metal fluorides. Reported here is the development of a simple strategy for deoxyfluorination, using first‐row transition‐metal fluorides, and it overcomes these limitations. Using CuF2 as an exemplar, activation of an O‐alkylisourea adduct, formed in situ, allows effective nucleophilic fluoride transfer to a range of primary and secondary alcohols. Spectroscopic investigations have been used to probe the origin of the enhanced reactivity of CuF2. The utility of the process in enabling 18F‐radiolabeling is also presented. 相似文献
162.
Evin AHN SADIK Hamdi Melih SARAOLU lke GÜROL Mehmet Ali EBEOLU Fatma Emel KOAK 《Turkish Journal of Chemistry》2020,44(5):1293
Determining the blood glucose level is important for the prevention and treatment of diabetes mellitus. We developed a sensor system using Quartz Crystal Microbalance (QCM) to determine the blood glucose level from human blood serum. This study consists of two experimental stages: artificial glucose/pure water solution tests and human blood serum tests. In the first stage of the study, the QCM sensor with the highest performance was identified using artificial glucose solution concentrations. In the second stage of the study, human blood serum measurements were performed using QCM to determine blood glucose levels. QCM sensors were coated with phthalocyanines (Pcs) by jet spray method. The blood glucose values of 96 volunteers, which ranged from 71 mg/dL to 329 mg/dL, were recorded. As a result of the study, human glucose values were determined with an average error of 3.25%. 相似文献
163.
In an effort to resolve the existing discrepancy between experiment and theory, the cross-sections for the production ofL
l,L
α
,L
β
andL
γ
groups ofL-shell X-rays of Ho by photons of nine energies in the range 10–40 keV have been measured using an improved version of annular
source double reflection geometrical set-up. Contrary to the earlier findings of Garget al that the measured values of the cross-sections are consistently higher than those calculated theoretically, the present results
do not confirm this. The plausible deficiencies in the experiments of Garget al are pointed out and possible remedies to overcome them are suggested. It is concluded that the higher values obtained by
Garget al are probably due to systematic errors in their method of measurement. 相似文献
164.
The level structure of178Hf is interpreted on the basis of the population of the states following178Hf (d, d′),177Hf (d, p) and179Hf (d, t) reactions. Evidence for quadrupole and octupole vibrational bands and unmixed and intermixed two-quasiparticle configurations
is presented. 相似文献
165.
Md.Motin Seikh Chandrabhas NarayanaSachin Parashar A.K. Sood 《Solid State Communications》2003,127(3):209-214
Brillouin scattering experiments are carried out to study the surface acoustic waves in Nd0.5Sr0.5MnO3 as a function of temperature in the range of 40-300 K covering the metal-insulator and charge-ordering phase transitions. The surface modes include surface Rayleigh wave, pseudo-surface acoustic wave (PSAW) and high velocity PSAW. The observed softening of the sound velocities for the surface modes below paramagnetic to ferromagnetic transition, Tc is related to the softening of the C44 elastic constant. The subsequent hardening of the sound velocity below the charge ordering transition temperature Tco is attributed to the coupling of the acoustic phonon to the charge ordered state via long range ordering of the strong Jahn-Teller (JT) distortion. 相似文献
166.
Chauhan N Gupta S Singh N Singh S Islam SS Sood KN Pasricha R 《Journal of colloid and interface science》2011,363(1):42-50
We depict a novel strategy exploiting the chemistry of metal ion adsorption for detection and sequestration of toxic heavy metal from processed water using gold nanoparticles capped with 4-aminothiophenol. The interaction between 4-aminothiophenol capped gold nanoparticles and heavy metal ions was studied as a function of time and concentration using TEM, HRTEM, SEM, EDS, and I-V characterization. Experiments confirmed that pH is one of the crucial controlling parameters. Adsorption capacity was monitored using AAS, UV-vis spectroscopy and I-V measurement. In the absence of any alloy formation between Au and heavy metal ions, the desorption of the heavy metal ions from 4-aminothiophenol capped gold nanoparticles surface by pH modulation serves as a mean of collection of heavy metal ions. Experiments revealed that the concentration of heavy metal ions in processed water after adsorption is below the maximum permissible limit set by the WHO. 相似文献
167.
A geometrically polar granular rod confined in 2D geometry, subjected to a sinusoidal vertical oscillation, undergoes noisy self-propulsion in a direction determined by its polarity. When surrounded by a medium of crystalline spherical beads, it displays substantial negative fluctuations in its velocity. We find that the large-deviation function (LDF) for the normalized velocity is strongly non-Gaussian with a kink at zero velocity, and that the antisymmetric part of the LDF is linear, resembling the fluctuation relation known for entropy production, even when the velocity distribution is clearly non-Gaussian. We extract an analogue of the phase-space contraction rate and find that it compares well with an independent estimate based on the persistence of forward and reverse velocities. 相似文献
168.
We report unipolar resistive switching in ultrathin films of chemically produced graphene (reduced graphene oxide) and multiwalled carbon nanotubes. The two-terminal devices with yield >99% are made at room temperature by forming continuous films of graphene of thickness ∼20 nm on indium tin oxide coated glass electrode, followed by metal (Au or Al) deposition on the film. These memory devices are nonvolatile, rewritable with ON/OFF ratios up to ∼ 105 and switching times up to 10 μs. The devices made of MWNT films are rewritable with ON/OFF ratios up to ∼400. The resistive switching mechanism is proposed to be nanogap formation and filamentary conduction paths. 相似文献
169.
170.
D. Eilidh Sood Dr. Sue Champion Daniel M. Dawson Sonia Chabbra Dr. Bela E. Bode Dr. Andrew Sutherland Dr. Allan J. B. Watson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8538-8541
Deoxyfluorination is a primary method for the formation of C−F bonds. Bespoke reagents are commonly used because of issues associated with the low reactivity of metal fluorides. Reported here is the development of a simple strategy for deoxyfluorination, using first-row transition-metal fluorides, and it overcomes these limitations. Using CuF2 as an exemplar, activation of an O-alkylisourea adduct, formed in situ, allows effective nucleophilic fluoride transfer to a range of primary and secondary alcohols. Spectroscopic investigations have been used to probe the origin of the enhanced reactivity of CuF2. The utility of the process in enabling 18F-radiolabeling is also presented. 相似文献