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81.
In this paper, normal and tangential coefficients of restitution for gaseous molecules colliding with layerwise (single and few layers) graphene nanosheets were calculated using non-equilibrium molecular dynamics method. The normal and tangential coefficients of restitution depend on impact angle, velocity and landing position of projectiles. These parameters were evaluated computationally by implementation of several operations. Some differences were observed between proposed problem and macro-scale nature. The most notable difference was proportionality between the restitution coefficients and impact velocity, while in the case of macro-scale systems, they have inverse relation. Number of layers of graphene substrate does not contribute significantly to the normal and tangential coefficients of restitution. On the other hand, except for hydrogen, where its normal coefficient of restitution is approximately unity, the normal coefficient of restitution for other gasses increases as impact angle increases. Furthermore, tangential coefficients of restitution reduce with impact angle. These results can offer additional insights for further understanding the impact mechanisms and bombardment-related phenomena in low-dimensional materials. Presented results could be utilised to optimise some applied operations such as porosity generation via bombardment of layered nanostructures, gas detection process, thermal management and pressure sensor applications.  相似文献   
82.
Seed germination is greatly influenced by both temperature (T) and water potential (ψ) and these factors largely determine germination rate (GR) in the field. Quantitative information about T and ψ effects on seed germination in lemon balm (Melisa officinalis L.) is scarce. The main objective of this study was to quantify seed germination responses of lemon balm to T and ψ, and to determine cardinal temperatures in a laboratory experiment. A segmented model was used to describe the effects of ψ (i.e., T) on GR and other germination parameters. The segmented model estimates were 7.2 °C for base (T b), 28.9 °C for optimum (T o), 40.1 °C for ceiling temperature (T c) and 1.64 physiological days (f o) (equivalent to a GRmax of 0.610 d?1 and a thermal time of 35.6 °C days) to reach 50 % maximum germination in the control (0 MPa) treatment (R 2 = 0.99, RMSE = 0.005 day?1). The inherent maximum rate of germination (days) was calculated by the [GRmax = 1/f o] model. ψ affected cardinal temperatures. From 0 to ?0.76 MPa, when ψ increased, T b was a constant 7.2 °C to ?0.38 MPa and increased linearly to 20.1 °C as ψ decreased. T o and f o increased linearly from 28.9 to 30 °C, and from 1.64 to 5.4 day?1, respectively as ψ decreased. However, there was no signification difference in T o as ψ decreased nor did T c decrease from 40.1 to 35 °C as ψ decreased. T b, T c and GRmax were the sole parameters affected by ψ and could be used to characterize differences between ψ treatments with respect to GR at various Ts. Therefore, the segmented model and its parameters can be used in lemon balm germination simulation models.  相似文献   
83.
84.

Background  

Hypoxia-inducible factors (HIFs) are involved in adaptive and survival responses to hypoxic stress in mammals. In fish, very little is known about the functions of HIFs.  相似文献   
85.

Background  

Quantification of in-vivo biomolecule mass transport and reaction rate parameters from experimental data obtained by Fluorescence Recovery after Photobleaching (FRAP) is becoming more important.  相似文献   
86.
Ichthyological Research - A new species of ponyfish, Deveximentum mekranensis, is described based on specimens collected from the Gulf of Oman. The new species is distinguishable from its congeners...  相似文献   
87.
A novel mathematical model in the framework of a nonlinear integro-partial differential equation governing biofluids flow in fractured biomaterials is proposed, solved, verified, and evaluated. A semi-analytical solution is derived for the equation, verified by a mass-lumped Galerkin finite element method (FEM), and calibrated with two in vitro experimental datasets. The solution process uses separation of variables and results in explicit expression involving complete and incomplete beta functions. The proposed semi-analytical model shows reasonable agreements with the finite element simulator as well as with two in vitro experimental time series and can be successfully used to simulate biofluids (e.g. water, blood, oil, etc.) flow in natural and synthetic porous biomaterials.  相似文献   
88.
Lyme disease is an infectious disease caused by a spirochete Borrelia burgdorferi ZS7. This spirochete is most often spread by ticks. Single antibiotic therapy is sufficient for containment of the early stage progression of the disease but combinational therapy is more preferred in later stages. Research is in progress for the development of drugs against the pathogen, but till date no vaccines have been developed to effect the late stage infections. There is a rapid rise in the cases of antibiotic-resistant population which is more than 10% of the total infected individuals. In such condition vaccine becomes the sole alternative for prevention. Therefore effective treatment includes antibiotic combination and combination of antigenic surfaces (for vaccine preparation). Thus, a comprehensive list of drug targets unique to the microorganisms is often necessary. Availability of Borrelia burgdorferi ZS7 proteome has enabled insilico analysis of protein sequences for the identification of drug targets and vaccine targets. In this study, 272 essential proteins were identified out of which 42 proteins were unique to the microorganism. The study identified 15 membrane localized drug targets. Amongst these 15, molecular modeling and structure validation of the five membrane localized drug target proteins could only be achieved because of the low sequence identity of the remaining proteins with RCSB structures. These 3D structures can be further characterized by invitro and invivo studies for the development of novel vaccine epitopes and novel antibiotic therapy against Borrelia burgdorferi.  相似文献   
89.
Molecular Biology Reports - Muscle contraction stimulates a transient change of myogenic factors, partly related to the mode of contractions. Here, we assessed the response of IGF-1Ea, IGF-1Eb,...  相似文献   
90.
Mycopathologia - Otomycosis is a common finding in otorhinolaryngology clinics and is usually caused by species of Candida and Aspergillus, particularly black aspergilli. Meanwhile, other fungi can...  相似文献   
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