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951.
A series of novel TiO2/poly(aryl ether sulfone) ultrafiltration membranes with anti-fouling and self-cleaning properties was designed and prepared. First, anti-photocatalytic degraded fluorine contained polv(aryl ether sulfone) matrix(PAES-F) was synthesized. Then the composite membranes were prepared via TiO2 nanopartides and PAES-F polymer matrix by solution blending and non-solvent induced phase inversion methods. Further, separation efficiency, fouling behavior and self-cleaning property of the composite ultrafiltration(UF) membranes were investigated by dead-end filtration experiments using a polyacn lamide solution. The composite UF membranes exhibited outstanding self-cleaning efficiency and anti-photocatalytic degraded property after exposure to simulated sunliglit irradiation.The water flux recovery ratios(FRR)of the optimal composite UF membranes could reach 74.24%, which was attributable to photocatalytic degradation of the organic contaminant by TiO2. And the retention rates of the composite UF membranes could maintain over 97%, which indicated the excellent photocatalytic degradation resistance of the fluorine contained PAES-F matrix. The novel high perfomiance composite UF membranes have a broad application prospect in water treatment. 相似文献
952.
Hua‐Ming Xiao Xian Wang Xing Yang Feng Zheng Yu‐Qi Feng 《Journal of mass spectrometry : JMS》2019,54(3):239-249
Hydralazine has been widely employed in the development of drugs, derivatization reagents, and ligands. In the present work, we reported a new type of dehydrogenated ion [M ? H]+ that was produced from the hydralazine derivative of hexanal in electrospray ionization mass spectrometry (ESI‐MS). The formation of [M ? H]+ ions in the ESI‐MS was found to be independent on the mobile phase composition of the liquid chromatography and ESI source parameters. A series of hydralazine derivatives of aldehyde were investigated to confirm this phenomenon. The results showed that hydralazine derivatives of aldehydes that contained an sp3 hybridization carbon with a hydrogen at the α‐position of aldehydes could form the unexpected [M ? H]+ ions, whereas hydralazine derivative of acetone could only generate [M + H]+ ion in the ESI‐MS. We proposed the possible formation mechanism of [M ? H]+ ion for the hydralazine derivatives of aldehydes: the [M ? H]+ ion was possibly formed by the loss a hydrogen molecule (H2) from the protonated ion [M + H]+. The results obtained from density functional theory (DFT) calculations supported this proposed formation mechanism of [M ? H]+ ion. 相似文献
953.
Geng Tianfeng Du Chunyu Cheng Xinqun Xu Xing Jian Jiyuan He Xiaoshu Zuo Pengjian Yin Geping 《Journal of Solid State Electrochemistry》2019,23(1):101-108
Journal of Solid State Electrochemistry - Li-rich layered oxide (LrLO) cathode has attracted much attention for Li-ion batteries in recent years due to its superior capacity of exceeding... 相似文献
954.
955.
956.
Well Dispersed SnO2 Nanoclusters Preparation and Modulation of Metal-Insulator Transition Induced by Ionic Liquid 下载免费PDF全文
Zhong-hu Liu Xing Chen Yi-yu Zhu Si-han Zhao Zhi-qiang Wang Feng Wang Qiang-qiang Meng Lei Zhu Qin-fang Zhang Bao-lin Wang Le-le Fan 《化学物理学报(中文版)》2019,32(2):248-252
Tin dioxide (SnO2) has attracted broad interest due to its particular gas-sensor property. Nano- or atom-scale SnO2 material has always been the aim in order to ultimately improve the sensitivity. However, until now, it remains difficult to synthesize SnO2 nanoclusters by using traditional methods. In the present work, we have achieved the preparation of SnO2 nanoclusters by using the cluster beam deposition technique. The obtained nanoclusters were well characterized by high resolution transmission electron microscope HR-TEM. Results indicated the formation of the well-dispersed SnO2 nanoclusters with uniform size distribution (5-7 nm). Furthermore, an obvious metal insulator transition was observed by gating with ionic liquid. Combined with theory calculation, the corresponding mechanism was systematically analyzed from oxygen vacancy induced electron doping. 相似文献
957.
A mathematical model is developed to control aircraft vibrations caused by runway excitation using an active landing gear system. Equations are derived to describe the integrated aircraft-active system. The nonlinear characteristics of the system are modelled and it is actively controlled using a Proportional Integral Derivative (PID) strategy. The performance of this system and its corresponding passive system are compared using numerical simulations. It is demonstrated that the impact loads and the vertical displacement of the aircraft's centre of gravity caused by landing and runway excitations are greatly reduced using the active system, which result in improvements to the performance of the landing gear system, benefits the aircraft's fatigue life, taxiing performance, crew/passenger comfort and reduces requirements on the unevenness of runways. 相似文献
958.
Xing Wang Shao-Feng Wu Shu Zhu Jin-Hua Yue Guo-Hong Yang 《International Journal of Theoretical Physics》2008,47(5):1230-1239
Using the relationship between the entropy and the Euler characteristic, an entropy density is introduced to describe the
inner topological structure of the entropy of 4-dimensional axisymmetric black holes. It is pointed out that the density of
entropy is determined by the singularities of the timelike Killing vector field of spacetime, and these singularities carry
the topological numbers, Hopf indices and Brouwer degrees, which are topological invariants. At last, Kerr–Newman black hole
as an example of axisymmetric black holes is given. What’s more, the entropy and the latent heat of the topological phase
transition of the black hole mentioned above are calculated and the latent heat just lies in the range of the energy of gamma
ray bursts.
This work is supported in part by the NSFs of China under Grant No. 10575068 and of Shanghai Municipal Committee of Science
and Technology under Grant No. 04ZR14059 and Shanghai Leading Academic Discipline Project under Project Number: T0104. 相似文献
959.
Ling-Ling Xing 《Journal of Physics and Chemistry of Solids》2008,69(9):2341-2343
Using the assumption δT=δT0(V/V0)k and the Grüneisen parameter γ macroscopic definition expression, we obtained a relationship for the volume dependence of the Grüneisen parameter γ. We have calculated the Grüneisen parameter γ with this relationship for NaCl and ε-Fe at high pressure under study. The calculated values of γ are found to show fairly in good agreement with available experimental data. 相似文献
960.
Yejin Zhang Wanhua Zheng Mingxin Xing Gang Ren Hailing Wang LiangHui Chen 《Optics Communications》2008,281(10):2774-2778
The exact calculation of mode quality factor Q is a key problem in the design of high-Q photonic crystal nanocavity. On the basis of further investigation on conventional Pade approximation, FDM and DFT, Pade approximation with Baker’s algorithm is enhanced through introducing multiple frequency search and parabola interpolation. Though Pade approximation is a nonlinear signal processing method and only short time sequence is needed, we find the different length of sequence requirements for 2D and 3D FDTD, which is very important to obtain convergent and accurate results. By using the modified Pade approximation method and 3D FDTD, the 2D slab photonic crystal nanocavity is analyzed and high-Q multimode can be solved quickly instead of large range high-resolution scanning. Monitor position has also been investigated. These results are very helpful to the design of photonic crystal nanocavity devices. 相似文献