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排序方式: 共有289条查询结果,搜索用时 15 毫秒
101.
A PCR amplification method without DNA extraction   总被引:1,自引:0,他引:1  
Li H  Xu H  Zhao C  Sulaiman Y  Wu C 《Electrophoresis》2011,32(3-4):394-397
To develop a simple and inexpensive method for direct PCR amplification of animal DNA from tissues, we optimized different components and their concentration in lysis buffer systems. Finally, we acquired the optimized buffer system composed of 10?mmol tris(hydroxymethyl)aminomethane (Tris)-Cl (pH 8.0), 2?mmol ethylene diamine tetraacetic (EDTA) (pH 8.0), 0.2?mol NaCl and 200?μg/mL Proteinase K. Interestingly, the optimized buffer is also very effective when working with common human sample types, including blood, buccal cells and hair. The direct PCR method requires fewer reagents (Tris-Cl, EDTA, Protease K and NaCl) and less incubation time (only 35?min). The cost of treating every sample is less than $0.02, and all steps can be completed on a thermal cycler in a 96-well format. So, the proposed method will significantly improve high-throughput PCR-based molecular assays in animal systems and in common human sample types.  相似文献   
102.
We present new kinds of Hardy integral inequalities involving some generalization and improvement.  相似文献   
103.
Swingle Nunes  S.  Sulaiman  S.B.  Sahoo  N.  Das  T.P.  Bharuth-Ram  K.  Frank  M.  Kreische  W.  Bonde Nielsen  K. 《Hyperfine Interactions》1999,120(1-8):151-155
The Hartree-Fock cluster procedure was used to obtain the associated electronic distributions for 19F* (I = 5/2, E x = 197 KeV excited nuclear state of the 19F atom) at possible sites in crystalline Si, Ge and diamond and to calculate nuclear quadrupole coupling constants v Q and the asymmetry parameter η of the electric field gradient at the modelled sites. Lattice relaxation effects have been incorporated by employing a geometry optimization method to obtain minimum energy configurations for the clusters modelling each site. The intrabond (IB), antibonding (AB) and substitutional (S) sites in the bulk and the atop site on the surface were studied. From a comparison with v Q and η values observed in time differential perturbed angular distribution (TDPAD) measurements we were able to identify the high frequency component in Si and Ge with 19F* at the intrabond site. In diamond two high frequency components are observed. These are identified with 19F* at intrabond and substitutional sites. For the low frequency site in Si and Ge the assignment is made to 19F* implants at dangling bonds in the bulk resulting from implantation damage. In diamond none of the sites studied could provide lower frequency nuclear quadrupole parameters close to the observed ones. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
104.
Microfiber Mach Zehnder Interferometer (MMZI) is demonstrated by micromanipulating an optical microfiber drawn from a single mode fiber (SMF) using a flame brushing technique. The MMZI shows good interference fringes with an extinction ratio of 13 dB and a free spectral range (FSR) of 0.52 nm at 1530 nm. The MMZI is then embedded in a polymer with the refractive index of 1.36 to increase the stability and robustnes of the device. It is found that the transmission spectrum of the packaged MMZI is changed by the polymer, which increases the FSR to 0.83 nm. The degradation in transmission loss and extinction ratio are attributed to the disturbance at the coupling area during the packaging. Compared with waveguide based mach zehnder interferometer, the proposed MMZI is favoured due to easy fabrication, compact size, and easy integration with the fiber system.  相似文献   
105.
The location of the positive muon used as a probe in highT c systems is investigated using the unrestricted Hartree-Fock cluster procedure. Our calculations indicate that + is located in thea–c plane at a distance of 1.08 Å from the apical oxygen at a +-O(a)-Cu angle of 25°. The hyperfine field at this site is also calculated. Our results show the importance of including the local contact and dipolar contributions to the hyperfine field which arise from the unpaired electron spin distribution in the vicinity of the muon.  相似文献   
106.
In this paper, ZnSTe quantum dots-based hybrid solar cells (HSC) with two different device architectures have been investigated. The improved performance of the poly(3-hexylthiophene) (P3HT) and [6,6]phenyl C71 butyric acid methyl ester (PC71BM)-based bulk heterojunction (BHJ) solar cells by the incorporation of ZnSTe quantum dots (QDs) with an average size of 2.96 nm in PEDOT:PSS layer and active layer that have been demonstrated. Although the efficiency of both types of devices is almost the same, a close comparison reveals different reasons behind their improved performance. The device prepared with QDs in the HTL has shown reduced series resistance, increased shunt resistance, and improved mobility. On the other hand, QDs in the photoactive layer demonstrates increased photo-generation leading to improved efficiency.  相似文献   
107.
This study successfully reveals the dark, singular solitons, periodic wave and singular periodic wave solutions of the (1+1)-dimensional coupled nonlinear Schrödinger equation by using the extended rational sine-cosine and rational sinh-cosh methods. The modulation instability analysis of the governing model is presented. By using the suitable values of the parameters involved, the 2-, 3-dimensional and the contour graphs of some of the reported solutions are plotted.  相似文献   
108.
This paper studies the new families of exact traveling wave solutions with the modified nonlinear Schrödinger equation, which models the propagation of rogue waves in ocean engineering. The extended Fan sub-equation method with five parameters is used to find exact traveling wave solutions. It has been observed that the equation exhibits a collection of traveling wave solutions for limiting values of parameters. This method is beneficial for solving nonlinear partial differential equations, because it is not only useful for finding the new exact traveling wave solutions, but also gives us the solutions obtained previously by the usage of other techniques (Riccati equation, or first-kind elliptic equation, or the generalized Riccati equation as mapping equation, or auxiliary ordinary differential equation method) in a combined approach. Moreover, by means of the concept of linear stability, we prove that the governing model is stable. 3D figures are plotted for showing the physical behavior of the obtained solutions for the different values of unknown parameters with constraint conditions.  相似文献   
109.
This study investigates the (3+1)-dimensional soliton equation via the Hirota bilinear approach and symbolic computations. We successfully construct some new lump, lump-kink, breather wave, lump periodic, and some other new interaction solutions. All the reported solutions are verified by inserting them into the original equation with the help of the Wolfram Mathematica package. The solution's visual characteristics are graphically represented in order to shed more light on the results obtained. The findings obtained are useful in understanding the basic nonlinear fluid dynamic scenarios as well as the dynamics of computational physics and engineering sciences in the related nonlinear higher dimensional wave fields.  相似文献   
110.
We report newly designed pressure and displacement capacitive sensors based on a flexible paper–CNT structure.The carbon nanotube(CNT)powder was deposited on a thin paper substrate and was pressed at an elevated temperature.The sheet resistance of the paper–CNT films was in the range of 2–4 kΩ/cm2.The paper–CNT films were used to fabricate pressure and displacement sensors.The sensitivities of the pressure and the displacement sensors were found to be17.3 p F·m2/k N and 0.93 10-3p F/μm,respectively.The experimental results were compared with the simulated data and they found good agreement with each other.  相似文献   
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