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91.
92.
Du Jinzhou Dong Wenming Wang Xiangke Liu Heng Tao Zuyi 《Journal of Radioanalytical and Nuclear Chemistry》1998,238(1-2):183-185
The purpose of this work was to label polyclonal antibodies with99mTc such as photoactivated IgG and to check the radiochemical and biological behavior of the labeled product. Experiments were
carried out to found the formulation of optimal binding of99mTc to polyclonal IgG. In addition animal studies in normal mice and in mice bearing a promoted inflammation foci were performed.
The labeled product was analyzed by size-exclusion HPLC and ITLC. Higher amount than 23μg of tin per 500μg of protein gave
between 87% and 93% labeling. Protein concentrations between 1.5 and 5 mg/ml gave 90% labeling yields. 相似文献
93.
We consider two classes of the second-order Hamiltonian systems with symmetry. If the systems are asymptotically linear with resonance, we obtain infinitely many small-energy solutions by minimax technique. If the systems possess sign-changing potential, we also establish an existence theorem of infinitely many solutions by Morse theory. 相似文献
94.
浸渍金属盐二次活化制备中孔沥青基球形活性炭的研究 总被引:3,自引:1,他引:2
以煤焦油沥青为原料,水蒸气活化法制备具有一定孔隙结构的预活化沥青基球形活性炭:通过在预活化球形活性炭中浸渍Fe(NO3)3、Co(NO3)2、Ni(NO3)2水蒸气二次活化,制备得到具有不同中孔孔径分布和较高强度的球形活性炭;研究了金属Fe、CO、Ni在二次活化过程中对预活化球形活性炭的孔结构参数和VB12吸附性能的影响,实验结果表明,预活化球形活性炭通过浸渍硝酸盐二次活化能够有效提高中孔孔容和中孔含量,其中浸渍CO(NO3)2二次活化对中孔孔容的增加最为明显,其中孔孔容达0.50cm3/g,占总孔孔容的65%.随着浸溃Co(NO3)2二次活化时间的延长,预活化球形活性炭中孔孔容增加,孔径分布变宽. 相似文献
95.
An efficient copper-catalyzed multicomponent reaction of phenols, amides, and 4-bromphenyl iodide was developed that uses commercially available N,N-dimethylglycine as the ligand. This multicomponent reaction proceeds in moderate to good yields for a range of phenols and amides. The simple experimental procedure and high levels of functional group compatibility make this method attractive for applications on pesticides. 相似文献
96.
In this article, a novel “off–on” fluorescent probe 2-(pyren-1-ylmethylene)-1H-indene-1,3(2H)-dione ( PID ) for Hg2+ was designed and synthesized. The selectivity, concentration titration, pH titration, time dependence, limit of detection, and recognition mechanism of PID for Hg2+ in CH3CH2OH/H2O solution were also investigated. The results indicated that PID exhibited high selectivity, sensitivity, and fast response to Hg2+, and the limit of detection was as low as 20.7 nmol/L. In addition, PID could work in a wide pH range, and the determination of Hg2+ in water samples showed that it could be used as a potential detection tool in practical application. 相似文献
97.
Wenming Jiang Jiang Bian Song Gao Mingcan Chen Shilin Du 《Journal of Dispersion Science and Technology》2017,38(5):671-676
Surface tension is an important thermodynamic parameter. In researching the removal mechanism of CO2 in natural gas in supersonic expansion process, the most basic and important task is to calculate the surface tension of CO2 under low-temperature and high-pressure condition. In this paper, a comparative study on the relevant calculation methods is carried out and the computational method applied to simulate the phase transition of CO2 supersonic condensation is selected. On this basis, the CO2 surface tension calculation model is modified and the calculation method, by using the piecewise function, is proposed. The results show that the average deviation of the piecewise function is only 0.95%, which is lower than the deviation of any single correlation. It can achieve an accurate prediction of the surface tension of the liquid CO2. 相似文献
98.
Multi-step temperature control in a polymerase chain reaction (PCR) is a limiting factor in device miniaturization and portability.
In this study, we propose the fabrication of a three-dimensional (3D) microdevice employing a single heater to minimize temperature
control required for an on-chip continuous-flow PCR as well as the overall footprint by stacking the device in multi-layers.
Two poly(dimethylsiloxane) (PDMS) layers with differing thicknesses are vertically stacked with their microchannel-engraved
sides facing down. Through-holes are made in the thicker PDMS layer, which is sandwiched between a glass substrate at the
bottom and the thinner PDMS layer at the top. In this way, a fluidic conduit is realized in a 3D configuration. The assembled
3D microdevice is then placed onto a heater glass-side down. The interface of the two PDMS layers displays a relatively lower
temperature than that of the PDMS and glass layers due to the low thermal conductivity of the PDMS and its physical distance
from the heater. The denaturation temperature can be controlled by adjusting the temperature of the heater, while the annealing/extension
temperature can be controlled automatically by molding the thicker bottom PDMS layer into the appropriate thickness calculated
using a numerical derivation proposed in this study. In this way, a cumbersome temperature measurement step is eliminated.
DNA amplification was successfully carried out using the proposed 3D fluidic microdevice, and the intensity of the resulting
amplicon was comparable to that obtained using a thermal cycler. This novel concept of adopting a single heating source greatly
simplifies the temperature control issue present in an on-chip continuous-flow PCR. It also allows the use of a commercialized
hot plate as a potential heat source, paving the way for device miniaturization and portability in a highly cost-effective
manner. In this study, a simple and facile technique to make arrays of through-holes for the fluidic interconnection inside
a 3D channel configuration is also addressed. 相似文献
99.
Internucleotide 2hJNN spin‐spin couplings and chemical shifts (δ(1H) and Δδ(15N)) of N? H···N H‐bond units in the natural and radiation‐damaged G‐C base pairs were predicted using the appropriate density functional theory calculations with a large basis set. Four possible series of the damaged G‐C pairs (viz., dehydrogenated and deprotonated G‐C pairs, GC?? and GC?+ radicals) were discussed carefully in this work. Computational NMR results show that radicalization and anionization of the base pairs can yield strong effect on their 2hJNN spin scalar coupling constants and the corresponding chemical shifts. Thus, variations of the NMR parameters associated with the N? H···N H‐bonds may be taken as an important criterion for prejudging whether the natural G‐C pair is radiation‐damaged or not. Analysis shows that 2hJNN couplings are strongly interrelated with the energy gaps (ΔELP→σ*) and the second‐order interaction energies (E(2)) between the donor N lone‐pair (LPN) and the acceptor σ*N? H localized NBO orbitals, and also are sensitive to the electron density distributions over the σ*(N? H) orbital, indicating that 2hJNN couplings across the N? H···N H‐bonds are charge‐transfer‐controlled. This is well supported by variation of the electrostatic potential surfaces and corresponding charge transfer amount between G and C moieties. It should be noted that although the NMR spectra for the damaged G‐C pair radicals are unavailable now and the states of the radicals are usually detected by the electron spin resonance, this study provides a correlation of the properties of the damaged DNA species with some of the electronic parameters associated with the NMR spectra for the understanding of the different state character of the damaged DNA bases. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011. 相似文献
100.
Tetraphenylethylene (TPE) based molecules with easy synthesis, good thermal stability, and especially their aggregation‐induced emissions enhancement (AIEE) effect recently become attractive organic emitting materials due to their potentially practical application in OLEDs. Herein, the AIEE behaviors of tetraphenylethylene dyes (TMTPE and TBTPE) were investigated. Fabricated luminesent device using TMTPE dye as emitting layer displays two strong emitting bands: the blue emission coming from the first‐step aggregation and the yellow emission attributed to the second‐step aggregation. Thus, it can be utilized to fabricate the white‐light OLEDs (WOLEDs) of the single‐emitting‐component. A three‐layer device with the brightness of 1200 cd·m?2 and current ef?ciency of 0.78 cd·A?1 emits the close to white light with the CIE coordinates of x=0.333 andy=0.358, when applied voltage from 8–13 V, verifying that the TPE‐based dyes of AIEE effect can be effectively applied in single‐emitting‐component WOLEDs fabrication. 相似文献