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排序方式: 共有1292条查询结果,搜索用时 15 毫秒
1.
Alfredo M. Gravagnuolo Eden Morales‐Narváez Charlene Regina Santos Matos Sara Longobardi Paola Giardina Arben Merkoçi 《Advanced functional materials》2015,25(38):6084-6092
Class I hydrophobin Vmh2, a peculiar surface active and versatile fungal protein, is known to self‐assemble into chemically stable amphiphilic films, to be able to change wettability of surfaces, and to strongly adsorb other proteins. Herein, a fast, highly homogeneous and efficient glass functionalization by spontaneous self‐assembling of Vmh2 at liquid–solid interfaces is achieved (in 2 min). The Vmh2‐coated glass slides are proven to immobilize not only proteins but also nanomaterials such as graphene oxide (GO) and quantum dots (QDs). As models, bovine serum albumin labeled with Alexa 555 fluorophore, anti‐immunoglobulin G antibodies, and cadmium telluride QDs are patterned in a microarray fashion in order to demonstrate functionality, reproducibility, and versatility of the proposed substrate. Additionally, a GO layer is effectively and homogeneously self‐assembled onto the studied functionalized surface. This approach offers a quick and simple alternative to immobilize nanomaterials and proteins, which is appealing for new bioanalytical and nanobioenabled applications. 相似文献
2.
Amnon H. Eden 《Minds and Machines》2007,17(1):121-123
3.
能源成本上涨速度高于纱线价格上涨速度,Autocoro纺纱厂每年的能耗成本约占每年营业额的5%,主要能耗是电能. 相似文献
4.
Unser M. Aldroubi A. Eden M. 《IEEE transactions on pattern analysis and machine intelligence》1991,13(3):272-277
Least squares approximation problems that are regularized with specified highpass stabilizing kernels are discussed. For each problem, there is a family of discrete regularization filters (R-filters) which allow an efficient determination of the solutions. These operators are stable symmetric lowpass filters with an adjustable scale factor. Two decomposition theorems for the z -transform of such systems are presented. One facilitates the determination of their impulse response, while the other allows an efficient implementation through successive causal and anticausal recursive filtering. A case of special interest is the design of R-filters for the first- and second-order difference operators. These results are extended for two-dimensional signals and, for illustration purposes, are applied to the problem of edge detection. This leads to a very efficient implementation (8 multiplies+10 adds per pixel) of the optimal Canny edge detector based on the use of a separable second-order R-filter 相似文献
5.
Fadwa T. Eljack Ahmed F. Abdelhady Mario R. Eden Frederico B. Gabriel Xiaoyun Qin Mahmoud M. El-Halwagi 《Computers & Chemical Engineering》2005,29(11-12):2304
Decoupling the constitutive equations from the balance and constraint equations allows for reformulating a conventional forward problem into two reverse problems. The first reverse problem is the reverse of a simulation problem, where the process model is solved in terms of the constitutive (synthesis/design) variables instead of the process variables, thus providing the synthesis/design targets. The second reverse problem (reverse property prediction) solves the constitutive equations to identify unit operations, operating conditions and/or products by matching the synthesis/design targets. Visualization of the problem is achieved by employing recently developed property clustering techniques, which allows a high-dimensional problem to be visualized in two or three dimensions. The clusters by definition satisfy intra-stream and inter-stream conservation through linear “mixing” rules, which allows for the development of consistent additive rules along with their ternary representation. 相似文献
6.
Mr.KoichiChujo 《国外电子测量技术》2003,22(6):2-3,6
本文着重论述了波形测量技术的最新发展趋势。 相似文献
7.
Summary Melan's classical shakedown theorem for continuous media considered as a problem of methematical programming with constraints is reformulated and reduced to a solution of a certain min-max problem. A similar approach is presented for the structural theory described in terms of generalized variables. A distinction is made between alternating plasticity and incremental collapse modes in the analysis of structures with nonsandwich cross-sections. 相似文献
8.
In examining the history of IBM in Chile, this article asks how IBM came to dominate Chile's computer market and, to address this question, emphasizes the importance of studying both IBM corporate strategy and Chilean national history. The article also examines how IBM reproduced its corporate culture in Latin America and used it to accommodate the region's political and economic changes. 相似文献
9.
The semi-analytical, analytical and direct methods for numerical structural shape sensitivity analysis are discussed for a beam model and the general three-dimensional case. While the two first methods are applied directly to the finite element model of a structure, the direct approach follows from a continuous formulation and only the final results can be discretized. 相似文献
10.
The mechanical properties of one of the new high strength polymer modified hydraulic cements have been investigated. An important parameter for the material is the amount of polymer present, and the properties are found to be dependent upon the degree of drying. For example, in the wet state, polymer content has little effect upon ultimate flexural strength, but does cause nonlinearity in the stress-strain behaviour. Although increasing polymer content causes a reduction in the initial tangent modulus, it is shown that retardation of hydration may account for this. In the dry state, increasing polymer content leads to increasing flexural strength, fracture toughness and failure strain, but leaves initial elastic modulus relatively unchanged. It is concluded that removal of pores is not the principal strengthening mechanism since strength increases are consequent upon water removal from the microstructure in the presence of the polymer. A fibrillar pull-out model is proposed to explain the observed behaviour of both wet and dry material and ordinary Portland cement paste, which shows good correlation with experimental results. The principal effect of the polymer is to act as an adhesive at the interface between interacting CSH fibrils. 相似文献