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排序方式: 共有249条查询结果,搜索用时 15 毫秒
1.
Journal of Porous Materials - Compared with traditional battery and super capacitor materials, nanomaterials can significantly improve ion transport and electron conductivity. There are many...  相似文献   
2.
Wireless Personal Communications - Matched filtering has found its way in many diverse applications such as communication, signal processing and more. The emphasis of this paper is on the design...  相似文献   
3.
Soomro  Fozia K.  Memon  Saima Q.  Memon  Najma  Khuhawar  M. Y. 《Polymer Bulletin》2020,77(5):2367-2383
Polymer Bulletin - In the present study, a Schiff’s base polymer (SBP) has been synthesized by the condensation of trifluoroacetylacetone and amino-polystyrene copolymer resin. After the...  相似文献   
4.
Microencapsulated phase-change materials (MPCM) can be used to develop a structural–functional integrated cement paste having high heat storage efficiency and suitable mechanical strength. However, the incorporation of MPCM has been found to degrade the mechanical properties of cement based composites. Therefore, in this research, the effect of carbon nanotubes (CNTs) on the properties of MPCM cement paste was evaluated. Test results showed that the incorporation of CNTs in MPCM cement paste accelerated the cement hydration reaction. SEM micrograph showed that CNTs were tightly attached to the cement hydration products. At the age of 28 days, the percentage increase in flexural and compressive strength with different dosage of CNTs was found to be up to 41% and 5% respectively. The optimum dosage of CNTs incorporated in MPCM cement paste was found to be 0.5 wt %. From the thermal performance test, it was found that the cement paste panels incorporated with different percentages of MPCM reduced the temperature measured at the center of the room by up to 4.6 °C. Inverse relationship was found between maximum temperature measured at the center of the room and the dosage of MPCM.  相似文献   
5.
Graphene sheets have been demonstrated to be the building blocks for various assembly structures, which eventually determine the macroscopic properties of graphene materials. As a new assembly structure, transparent macroporous graphene thin films (MGTFs) are not readily prepared due to the restacking tendency of graphene sheets during processing. Here, an ice crystal‐induced phase separation process is proposed for preparation of transparent MGTFs. The ice crystal‐induced phase separation process exhibits several unique features, including efficient prevention of graphene oxide restacking, easy control on the transparency of the MGTFs, and wide applicability to substrates. It is shown that the MGTFs can be used as porous scaffold with high conductivity for electrochemical deposition of various semiconductors and rare metal nanoparticles such as CdSe, ZnO, and Pt, as well as successive deposition of different materials. Notably, the macroporous structures bestow the MGTFs and the nanoparticle‐decorated MGTFs (i.e., Pt@MGTF and CdSe@MGTF) enhanced performance as electrode for oxygen reduction reaction and photoelectrochemical H2 generation.  相似文献   
6.
Sorption-enhanced-steam-reforming (SESR) is a thermochemical conversion technology that produces a high-purity hydrogen stream by utilizing in-situ removal of CO2 with a sorbent. In this paper, the advantages and disadvantages of CaO based sorbents, alkali-metal based sorbents (Na2ZrO3, Li2ZrO3 and Li4SiO4), hydrotalcite based sorbents, bifunctional materials and sorbents prepared from wastes are briefly discussed, and the techniques to improve the sorption properties of these CO2 sorbents are summarized. In the process of hydrogen production by sorption-enhanced-steam-reforming, the selection of suitable high-temperature CO2 sorbent is the key to produce high purity hydrogen. Furthermore, the hydrogen-production performance of the above-mentioned sorbents in the SESR process is investigated and summarized. Finally, a future perspective and some suggestions regarding these five types of sorbents are put forward.  相似文献   
7.
We present a hybrid model for content extraction from HTML documents. The model operates on Document Object Model (DOM) tree of the corresponding HTML document. It evaluates each tree node and associated statistical features like link density and text distribution across the node to predict significance of the node towards overall content provided by the document. Once significance of the nodes is determined, the formatting characteristics like fonts, styles and the position of the nodes are evaluated to identify the nodes with similar formatting as compared to the significant nodes. The proposed hybrid model is derived from two different models, i.e., one is based on statistical features and other on formatting characteristics and achieved the best accuracy. We describe the validity of model with the help of experiments conducted on the standard data sets. The results revealed that the proposed model outperformed other existing content extraction models. We present a browser based implementation of the proposed model as proof of concept and compare the implementation strategy with various state of art implementations. We also discuss various applications of the proposed model with special emphasis on open source intelligence.  相似文献   
8.
Carbon nanofiber based buckypaper used as a thermal interface material   总被引:1,自引:0,他引:1  
Carbon nanofiber (CNF) based buckypaper was explored as a potential thermal interface material (TIM) for electronics. CNFs were subjected to heat treatment temperatures of 1100 °C, 1500 °C and 3000 °C. TIMs were prepared and characterized using thermal impedance test stand. Results show that the thermal impedance at the interface decreased in conjunction with the increasing heat-treatment temperature of CNFs. TIMs with graphitized CNF exhibit a significant decrease of 54% in thermal impedance in comparison with the dry contact. This improvement is likely due to the high degree of CNF graphitizibility and the resulting outstanding electrical and thermal conductivities.  相似文献   
9.
This paper focused on a review of international experiences on fuel economy standard based on technologies available. It also attempts to identify savings possibilities and greenhouse gas (GHG) emissions reductions. It is known that road transport, particularly private cars are responsible for large, and increasing share of transport fuel use and emissions. With the implementation of fuel economy standard and label for motor vehicles, it will reduce the risks of increasing dependency on petroleum-based fuel and will increase the profit to consumers. The GHG emissions, which causing global warming, air pollution, diseases, etc. can be reduced as well. In this regard, advanced technologies such as, engine, transmission, and vehicle technologies may brought significant consumers and social benefits. Studies in developed countries have shown that fuel economy standard is beneficial for the society, government as well as the environment.  相似文献   
10.
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