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排序方式: 共有355条查询结果,搜索用时 140 毫秒
341.
Arkabandhu Chowdhury Hamim Zafar B. K. Panigrahi K. R. Krishnanand Ankita Mohapatra Zhihua Cui 《Memetic Computing》2014,6(2):85-95
Dynamic economic dispatch (DED) is one of the major planning problem in a power system. It is a non-linear optimization problem with various operational constraints, which includes the constraints of the generators operating characteristics and the system constraints. Its principal aim is to minimize the cost of power production of all the participating generators over a time horizon of 24 h, while satisfying the system constraints. This problem deals with non-convex characteristics if generation unit valve-point effects are taken into account. The paper intends to solve the DED problem with valve-point effects, using our modified form of Local-best variant of Particle Swarm Optimization (Lbest PSO) algorithm. We have tested our algorithm on 5-unit, 10-unit and 110-unit test system with non-smooth fuel cost functions to prove the effectiveness of the suggested method over different state of the art methods. 相似文献
342.
S. Balaji B. K. Panigrahi K. Saravanan C. David S. Amirthapandian S. Kalavathi K. G. M. Nair René Hübner 《Applied Physics A: Materials Science & Processing》2014,116(4):1595-1603
Fine Co and Pt nanoparticles are nucleated when a silica sample is implanted with 400 keV Co+ and 1370 keV Pt+ ions. At the implanted range, Co and Pt react to form small Co x Pt(1?x) nanoparticles during Si+ ion irradiation at 300 °C. Thermal annealing of the pre-implanted silica substrate at 1000 °C results in the formation of spherical nanoparticles of various sizes. When irradiated with Si+ ions at 300 °C, particles in the size range of 5–17 nm undergo rod-like shape transformation with an elongation in the direction of the incident ion beam, while those particles in the size range of 17–26 nm turn into elliptical shape. Moreover, it is suspected that very big nanoparticles (size >26 nm) decrease in size, while small nanoparticles (size <5 nm) do not undergo any transformation. During Si+ ion irradiation, the crystalline nature of the nanoparticles is preserved. The results are discussed in the light of the thermal spike model. 相似文献
343.
Single crystals of pure and Na+ doped Bisthiourea Sodium Nitrate (BTSN), semi organic crystal were grown by slow evaporation technique. The grown crystals were subjected to various studies such as single crystal X-ray diffraction (XRD), UV–vis studies, Fourier transform infrared (FTIR), TG–DTA, and Vickers's microhardness were also measured. Single crystal X-ray diffraction studies reveal the crystals belong to orthorhombic crystallographic system. The mechanical property of the grown crystal was determined by microhardness studies. 相似文献
344.
A system of two-dimensional photon gas has recently been realized experimentally. We show that this setup can be used to observe a universal breathing mode of photon gas and a modification in the experimental setup would open up a possibility of observing the Berezinskii–Kosterlitz–Thouless (BKT) phase transition in such a system. Furthermore, the universal jump in the superfluid density of light in the output channel can be used as an unambiguous signature for the experimental verification of the BKT transition. 相似文献
345.
We provide a number of schemes for the splitting up of quantum information among k parties using a N-qubit linear cluster state as a quantum channel, such that the original information can be reconstructed only if all the parties cooperate. Explicit circuits are provided for these schemes, which are based on the concept of measurement based locking and unlocking of quantum information. These are experimentally feasible as they require measurements to be performed only on product basis. 相似文献
346.
Roy A 《Combinatorial chemistry & high throughput screening》2011,14(4):303
The section on patent review will be focused in the areas of interest to the readers of CCHTS. The search was conducted using the following key words: combinatorial chemistry, high throughput screening, drug repurposing, chemical library, high content screening, drug discovery and natural products. All patents highlighted here are identified by the patent number issued either by the World Intellectual Property Organization or by a regional patent office. 相似文献
347.
348.
In this paper, we generalize the concept of asymptotic Hankel operators on H2(D) to the Hardy space H2(Dn) (over polydisk) in terms of asymptotic Hankel and partial asymptotic Hankel operators and investigate some properties in case of its weak and strong convergence. Meanwhile, we introduce ith-partial Hankel operators on H2(Dn) and obtain a characterization of its compactness for n > 1. Our main results include the containment of Toeplitz algebra in the collection of all strong partial asymptotic Hankel operators on H2(Dn). It is also shown that a Toeplitz operator with symbol φ is asymptotic Hankel if and only if φ is holomorphic function in L∞(Tn). 相似文献
349.
Babajan Banaganapalli Chaitanya Mulakayala Gowsia D Naveen Mulakayala Madhusudana Pulaganti Noor Ahmad Shaik Anuradha CM Raja Mohan Rao Jumana Yousuf Al-Aama Suresh Kumar Chitta 《Applied biochemistry and biotechnology》2013,171(7):1639-1657
Resveratrol (RVS) is a naturally occurring antioxidant, able to display an array of biological activities. In the present investigation, a new derivative of RVS, RVS(a), was synthesized, and its biological activity was determined on U937 cells. It was observed that RVS(a) showed pronounced activity on U937 cells than RVS. RVS(a) is able to induce apoptosis in tumor cell lines through subsequent DNA fragmentation. From the EMSA results, it was evident that RVS(a) was able to suppress the activity of NFkB by interfering its DNA binding ability. Furthermore, the molecular interaction analysis (docking and dynamics) stated that RVS(a) has strong association with the IkB-alpha site of NFkB compared with RVS; this binding nature of RVS(a) might be prevent the NFkB binding ability with DNA. The present findings represent the potential activity of propynyl RVS on U937 cells and signifying it as a one of putative chemotherapeutic drugs against cancer. 相似文献
350.
Prabhakar PK Raj S Anuradha PR Sawant SN Doble M 《Colloids and surfaces. B, Biointerfaces》2011,86(1):146-153
Biocompatibility of medical grade polyurethane coated with polyaniline (PANi) and polyaniline-silver nanoparticle composite (PANi-AgNp) is reported here. These modified films showed 23 and 18% of 3T3 L1 cell death when compared to 41% with virgin polyurethane (PU) after 48h of incubation, respectively. All the surfaces elucidated inflammatory response in the form of enhanced expressions of the proinflammatory cytokines genes, TNF-α and IL-6. But these values were less (by 20%) on modified films than on the bare PU. Attachment of Pseudomonas and Bacillus were markedly less on PANi-AgNp coated surface (by 90.6 and 50.5%, respectively) when compared to the uncoated PU. As the CFU counts decreases on the nanoparticle coated PU, the adsorbed carbohydrate as well as protein content on to the surface of polymer decreases accordingly, indicating less attachment. A 20% reduction in the thickness of biofilm was observed in PANi-AgNp coated PU surface. A very strong positive correlation is observed between the contact angles of the polymers and the various biological parameters (namely colony forming units, protein, carbohydrate, cell death and inflammatory response), indicating hydrophilic surfaces prevent bacterial biofilm as well as are compatible to cells when compared to hydrophobic surfaces. Coating PU with PANi and PANi+AgNp renders the surface conductive, suggesting potential application in electrochemical biosensors. In addition, these modifications make the surface more biocompatible than the original PU. 相似文献