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41.
Unit Weight of Municipal Solid Waste   总被引:3,自引:0,他引:3  
The unit weight of municipal solid waste (MSW) is an important parameter in engineering analyses of landfill performance, but significant uncertainty currently exists regarding its value. A careful review of reliable field data shows that individual landfills have a characteristic MSW unit weight profile. Based on in situ unit weight data and trends observed in large-scale laboratory tests, a hyperbolic relationship was developed to represent this characteristic MSW unit weight profile. Within the context of this characteristic profile, landfill-specific values of MSW unit weight depend primarily on waste composition, operational practices (i.e., compaction, cover soil placement, and liquids management), and confining stress. Guidance is provided for developing landfill-specific MSW unit weight profiles, including procedures for performing large-scale tests for in situ measurement of MSW unit weight at a landfill.  相似文献   
42.
Arterial media calcification (AMC) is predominantly regulated by vascular smooth muscle cells (VSMCs), which transdifferentiate into pro-calcifying cells. In contrast, there is little evidence for endothelial cells playing a role in the disease. The current study investigates cellular functioning and molecular pathways underlying AMC, respectively by, an ex vivo isometric organ bath set-up to explore the interaction between VSMCs and ECs and quantitative proteomics followed by functional pathway interpretation. AMC development, which was induced in mice by dietary warfarin administration, was proved by positive Von Kossa staining and a significantly increased calcium content in the aorta compared to that of control mice. The ex vivo organ bath set-up showed calcified aortic segments to be significantly more sensitive to phenylephrine induced contraction, compared to control segments. This, together with the fact that calcified segments as compared to control segments, showed a significantly smaller contraction in the absence of extracellular calcium, argues for a reduced basal NO production in the calcified segments. Moreover, proteomic data revealed a reduced eNOS activation to be part of the vascular calcification process. In summary, this study identifies a poor endothelial function, next to classic pro-calcifying stimuli, as a possible initiator of arterial calcification.  相似文献   
43.
Wildcarded Identity-Based Encryption   总被引:1,自引:0,他引:1  
In this paper, we introduce a new primitive called identity-based encryption with wildcards, or WIBE for short. It allows a sender to encrypt messages to a whole range of receivers whose identities match a certain pattern. This pattern is defined through a sequence of fixed strings and wildcards, where any string can take the place of a wildcard in a matching identity. Our primitive can be applied to provide an intuitive way to send encrypted email to groups of users in a corporate hierarchy. We propose a full security notion and give efficient implementations meeting this notion under different pairing-related assumptions, both in the random oracle model and in the standard model.  相似文献   
44.
Security Proofs for Identity-Based Identification and Signature Schemes   总被引:2,自引:0,他引:2  
This paper provides either security proofs or attacks for a large number of identity-based identification and signature schemes defined either explicitly or implicitly in existing literature. Underlying these is a framework that on the one hand helps explain how these schemes are derived and on the other hand enables modular security analyses, thereby helping to understand, simplify, and unify previous work. We also analyze a generic folklore construction that in particular yields identity-based identification and signature schemes without random oracles. A preliminary version of this paper appears in Advances in Cryptology—EUROCRYPT 2004, volume 3027 of Lecture Notes in Computer Science, C. Cachin and J. Camenisch, eds., Springer-Verlag, 2004. This is the full version. Mihir Bellare: Supported in part by NSF grants CCR-0098123, ANR-0129617, CCR-0208842, CNS-0524765, and a gift from Intel Corporation. Chanathip Namprempre: Supported in part by the above-mentioned grants of first author and the Thailand Research Fund. Part of this work was done while the author was at University of California, San Diego. Gregory Neven: Work done while at Katholieke Universiteit Leuven, Belgium, supported by a Research Assistantship and a Postdoctoral Fellowship from the Fund for Scientific Research—Flanders.  相似文献   
45.
Renewable energies are gaining importance in urban management and in the planning of new residential and mixed‐use areas. Attention is also paid to self‐sufficiency, as the public electrical grid is strained through the integration of renewables. Here, an energy supply concept for an urban residential area in the planning phase is discussed to meet both economic and ecologic criteria. Based on the demand, different technical options are analyzed. The integration of renewables is coupled with energy storage to increase the self‐sufficiency of the residential area. The economic feasibility of the energy supply concept depends on the requirements to be met as well as the regulatory framework. With the currently available technology and the regulatory framework in place, self‐sufficiency and economic feasibility are opposing targets.  相似文献   
46.
47.
Skutterudite‐type pnictides based on CoSb3 are promising semiconductor materials for thermoelectric applications. An exhaustive structural characterization by synchrotron X‐ray powder diffraction of different M‐filled CoSb3 (M = Y, K, Sr, La, Ce, Yb) skutterudites, with a panoply of M atoms with very different chemical nature, allows to better understand the effects of filling from a crystallo‐chemical point of view. These analyses focus on the correlation of chemical and structural features with the enhanced thermoelectric properties displayed by certain families of filled‐CoSb3 skutterudites. These are mainly determined by Sb positional parameters, yielding Oftedal plots that depend on the filling fraction, ionic state, and atomic radius of the filler. Together with the distortion of [Sb4] rings and [CoSb6] octahedra present in the skutterudite structure, these results are linked to the band‐convergence concept and its influence on the thermoelectric transport properties. Here, the structural changes observed in the different chemical compositions are relevant to understand the improved thermoelectric performance of single partially filled n‐type skutterudites.  相似文献   
48.
The European Union's environmental legislation related to environmental protection, already implemented in the national legislation of the Republic of Croatia, aims to introduce a system of integrated and sustainable waste management. Within such a system, it is of utmost importance to have a better estimate of the amount of municipal waste generated, which directly influences future planning in the waste management sector. The aim of this research was to develop and optimize models for the estimation of generated municipal waste by application of methodology using neural network models, and taking into account the socio‐economic impact as well as the inputs regarding the actual waste management trends. In this paper, an artificial neural network models were used to predict the municipal waste generation in Zagreb, Croatia. The standardized socio‐economic and waste management variables were chosen to encompass 2013 to 2016 period. Moreover, the test prediction of the observed data was performed for 2017. Developed models sufficiently predicted the quantities of different municipal waste fractions and in that sense can contribute to better planning of upcoming waste management systems that will be sustainable and in order to meet the European Union commitments.  相似文献   
49.
Colorectal cancer (CRC) is the third most common cancer worldwide. The high mortality from CRC is mainly related to metastasis affecting distant organs and their function. Dissemination of tumor cells from the primary tumor and hematogeneous spread are considered crucial in the formation of tumor metastases. The analysis of circulating tumor cells (CTCs) and CTC clusters in the blood can be used for the early detection of invasive cancer. Moreover, CTCs have a prognostic significance in the monitoring of a malignant disease or the response to chemotherapy. This work presents an overview of the research conducted on CTCs with the aim of finding suitable detection systems and assessing the possibility of clinical applications in patients with CRC.  相似文献   
50.
The process of sintering of magnesium oxide obtained from sea-water is studied. The sample thickening stage in the isothermal sintering is determined to establish the manner of pore elimination in the process. The process of isothermal sintering of magnesium oxide is described mathematically to obtain a better insight into the process, in terms of a function giving the best possible correspondence between theoretical and experimental data.  相似文献   
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