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101.
可持续发展通道及预警研究   总被引:21,自引:0,他引:21  
阐述了可持续发展的组合 S型发展机制 ;探讨了可持续发展条件 ;提出了可持续发展通道的概念 ;构建了多阶段可持续发展趋势模型、可持续发展通道、可持续发展预警系统 ;给出了一个应用实例  相似文献   
102.
目的研究早期进入ICU监护治疗的方式对救治重型颅脑损伤患者的影响。方法选择2013年1月—2015年7月收治的200例重型颅脑损伤患者作为研究对象,随机分为治疗组和对照组,每组100例。对照组采用常规普通病房治疗,治疗组采用早期进入ICU监护治疗。观察比较两组患者实施各项治疗措施所需时间、治疗4周内病死率、治疗4周后生存患者平均神经功能缺损(NIHSS)评分、治疗4周后生存患者平均Barthel指数评分。结果治疗组在人工辅助通气道建立、高热缓解、术前准备等各项治疗措施平均耗时显著少于对照组(P0.05)。治疗组治疗4周内病死率2.0%,显著低于对照组病死率10.0%(P0.05)。治疗4周后,治疗组生存患者平均神经功能缺损评分显著低于对照组(P0.05),治疗组生存患者平均Barthel指数评分显著高于对照组(P0.05)。结论早期进入ICU监护治疗的方式对救治重型颅脑损伤患者治疗效果显著,能够更快的完成治疗措施、改善预后、改善神经功能恢复情况、降低死率。  相似文献   
103.
The two forms of transthyretin differing slightly in the tertiary structure, despite the presence of five mutations, show radically different properties in terms of susceptibility to the amyloid transformation process. These two forms of transthyretin are the object of analysis. The search for the sources of these differences was carried out by means of a comparative analysis of the structure of these molecules in their native and early intermediate stage forms in the folding process. The criterion for assessing the degree of similarity and differences is the status of the hydrophobic core. The comparison of the level of arrangement of the hydrophobic core and its initial stages is possible thanks to the application of divergence entropy for the early intermediate stage and for the final forms. It was shown that the minimal differences observed in the structure of the hydrophobic core of the forms available in PDB, turned out to be significantly different in the early stage (ES) structure in folding process. The determined values of divergence entropy for both ES forms indicate the presence of the seed of hydrophobic core only in the form resistant to amyloid transformation. In the form of aggressively undergoing amyloid transformation, the structure lacking such a seed is revealed, being a stretched one with a high content of β-type structure. In the discussed case, the active presence of water in the structural transformation of proteins expressed in the fuzzy oil drop model (FOD) is of decisive importance for the generation of the final protein structure. It has been shown that the resistant form tends to generate a centric hydrophobic core with the possibility of creating a globular structure, i.e., a spherical micelle-like form. The aggressively transforming form reveals in the structure of its early intermediate, a tendency to form the ribbon-like micelle as observed in amyloid.  相似文献   
104.
An electrochemical atomic force microscope was used to characterize the early stage of corrosion of an X100 pipeline steel in bicarbonate solutions with varied concentrations by synchronous measurements of electrochemical potential of the steel and its topographic evolution with time. Upon immersion of the steel in 0.01 M NaHCO3 solution, both electrochemical potential and topographic profile are associated with the dissolution of air‐formed oxides present on the steel surface. The potential drops and the surface roughness increases rapidly. When corrosion of the steel occurs, the potential further drops and the surface roughness of the steel increases gradually. As the steel corrosion achieves a steady state, the generation of corrosion products reaches a dynamic equilibrium state. The surface roughness maintain an approximately stable value. In solutions containing increased bicarbonate concentrations, such as 0.1 M and 0.5 M NaHCO3, the steel can be passivated. The formed passive film can eliminate some surface features and improves the surface roughness. The topographic profile of the steel surface in 0.5 M NaHCO3 solution is smoother than that in 0.1 M solution. The surface features within 20 nm become eliminated after 4500 s of immersion in 0.1 M NaHCO3 solution, while larger features within 50 nm in size are eliminated in 0.5 M NaHCO3 solution in the same time period. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
105.
Biofunctionalizing a simple and disposable graphene oxide-modified screen-printed carbon electrode with anti-interleukin-15 antibodies has been successfully demonstrated for the first time for the label-free electrochemical detection of interleukin-15, a biomarker of early HIV infection. To improve the electrochemical reactivity and introduce carboxylic groups on the surface of screen-printed carbon electrode, high-quality graphene oxide was used for the modification of screen-printed carbon electrode. With simple modification of the screen-printed carbon electrode, the device exhibited satisfactory sensitivity, selectivity, stability, reproducibility, and regenerability. The immunosensor provided a detection limit of 3.51?ng?mL?1 and a sensitivity of 0.5655?µA cm?2?mL?ng?1. The simply constructed immunosensor thus rendered promising device for immunoreactions on the surface of the electrode.  相似文献   
106.
一种基于重置的变结构前馈神经网络   总被引:1,自引:0,他引:1  
基于GaussNewton法的前馈神经网络虽然可以达到局部二阶收敛速度.但网络结构中如果结点个数过多,会造成过模拟;网络结点过少。又会导致不收敛。为了优化神经网络结构,尝试引入重置算法(Early Restart Algofithm),并将其应用于Gauss Newton前馈神经网络.提出基于重置的Gauss Newton变结构前馈神经网络。对比实验表明,重置算法的引入有效地解决神经网络的结构优化问题,优化后的神经网络具有良好的收敛性与稳定性。  相似文献   
107.
The generalized ray method (GRM) has been successfully used to study the transient elastic wave transmitting in the beams, planar trusses, space frames and infinite layered media. In this letter, the GRM is extended to investigate the early short time transient responses of laminated composite cylindrical shells under impact load. By using the Laplace transformation and referring to the boundary conditions, the ray groups transmitting in the finite laminated cylindrical shells under the shock load are obtained and the transient response related to each ray group can be derived via FFT algorithm. From the numerical results, it is shown that the early short time transient accelerations of the laminated composite cylindrical shell under impact loads are very large. But the short time transient shear strain and displacement are very small.  相似文献   
108.
We consider the problem of scheduling a set of dependent jobs on a single machine with the maximum completion time criterion. The processing time of each job is variable and decreases linearly with respect to the starting time of the job. Applying a uniform approach based on the calculation of ratios of expressions that describe total processing times of chains of jobs, we show basic properties of the problem. On the basis of these properties, we prove that if precedence constraints among jobs are in the form of a set of chains, a tree, a forest or a series–parallel digraph, the problem can be solved in O(n log n) time, where n denotes the number of the jobs.  相似文献   
109.
In many realistic scheduling settings a job processed later consumes more time than the same job processed earlier – this is known as scheduling with deteriorating jobs. Most research on scheduling with deteriorating jobs assumes that the actual processing time of a job is an increasing function of its starting time. Thus a job processed late may incur an excessively long processing time. On the other hand, setup times occur in manufacturing situations where jobs are processed in batches whereby each batch incurs a setup time. This paper considers scheduling with deteriorating jobs in which the actual processing time of a job is a function of the logarithm of the total processing time of the jobs processed before it (to avoid the unrealistic situation where the jobs scheduled late will incur excessively long processing times) and the setup times are proportional to the actual processing times of the already scheduled jobs. Under the proposed model, we provide optimal solutions for some single-machine problems.  相似文献   
110.
This paper considers some scheduling problems with deteriorating jobs. The objectives are to minimize the makespan, the total completion time, the total absolute deviation of completion time, the earliness, tardiness, and due date penalty, the sum of earliness penalties subject to no tardy jobs, respectively. We also explore two resource constrained scheduling problems: how to minimize the resource consumption with makespan constraints and how to minimize the makespan with the total resource consumption constraints. Several polynomial time algorithms are proposed to optimally solve the problems with the above objective functions.  相似文献   
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