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《International Journal of Engineering Science》2006,44(1-2):67-92
This article introduces an interdisciplinary subject of bioelectrodynamics in living organisms and its related research challenges and opportunities. Bioelectrodynamics in living organisms is aimed to reveal critical roles of electromagnetism and mechanics in biology, to correlate biophysical functions of living organisms with biochemical processes at the cellular level, and to introduce theoretical basis and methodology, such as modeling and simulations, for stimulating technical innovations and promoting technology development in biomedicine as well as for the study of human healthcare issues related to environments among others in our modern society. The article reviews some important issues in bioelectrodynamic modeling. This includes the modeling of living cells, blood, bones and soft tissues that may have unique properties, such as active control, regulation and remodeling capabilities that are completely different from those of conventionally man-made materials. Possible biological effects and potential biomedical usages of endogenous and exogenous electromagnetic fields and mechanical stresses in living organisms are also reviewed, which indicate promising future of biomedical imaging and therapeutic methods based on bioelectrodynamic techniques. The fact that living organisms may have well-organized structures, actively controlled actions and responses, extremely sensitivity in electromagnetic fields and mechanical actions, and amazing signal amplification functions may not only cause complexity and variety of the biological world, but also create opportunities for technical innovations in biomedicine to improve future quality of human life. 相似文献
44.
Rencheng Jin Guihua Li Yanbin Xu Junshen Liu Gang Chen 《International Journal of Hydrogen Energy》2014
Hierarchical Bi2S3 hollow spheres have been synthesized by a facile solvothermal process in the presence of sodium tartrate. The hollow spheres are composed of numerous ultrathin nanorods with the average diameter of 15 nm. Based on the time dependent electron microscope observations, the formation mechanism of such hierarchical structures has been proposed as a sodium tartrate directed self-assembled process and oriented attachement mechanism. The morphology and size of the subunits can be controlled by adjusting the amount of sodium tartrate. The Nitrogen adsorption-desorption measurements suggest that mesopores exist in these hollow spheres. The as-derived Bi2S3 hollow spheres exhibit excellent electrochemical hydrogen storage properties. 相似文献
45.
In a recent paper (ISA Transactions (2015)58: 58–66), an integral inequality has been proposed to reduce the conservativeness of stability conditions for Lur׳e uncertain systems. We point out that there exist some errors in Theorems 1–8, and the correct theorems are presented. Finally, the allowable maximum admissible upper bound (MAUB) listed in Table 1, Table 2, Table 3, Table 4, Table 5 have been recalculated by using the correct results. 相似文献
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《International Journal of Hydrogen Energy》2019,44(44):24162-24173
The human life faces serious energy shortage and environmental pollution problems, therefore developing a facile and environmental friendly strategy for synthesizing nanoparticles (NPs) with improved photocatalytic activity could pave the way for different applications. In the present study, one-pot/in-situ fluorine-free synthesis process has been examined toward the solvothermal production of anatase TiO2 nanoparticles with exposed facet orientation. This is an aim to achieve the excellent photocatalytic/photoelectrocatalytic performance. Most importantly addressing the global energy shortage, the synthesized TiO2 NPs represent superior performance in photoelectrocatalytic water splitting toward hydrogen production. The overpotential required to drive the hydrogen evolution reaction was −391, −346 and −283 mV vs. Ag/AgCl for P25, cubic and truncated octahedral NPs, respectively. Additionally, TiO2 NPs with exposed facets represent excellent photocatalytic performance toward environmental purification. As synthesized nanoparticles was examined via photocatalytic degradation of Acid Blue 5 and photocatalytic removal of NO gas. The enhanced photocatalytic and photoelectrocatalytic performance are associated to the effect of exposed facet orientation of final nanoparticles. 相似文献
48.
《International Journal of Hydrogen Energy》2019,44(57):30185-30195
Nowadays, energy shortage is one of the major problems in the world. Photocatalytic hydrogen production is a new type of energy technology with good application prospect. As a new type of photocatalytic semiconductor material, g-C3N4 has attracted much attention as a photocatalyst. By ultrasonic treatment of a mixed solution of g-C3N4 and bovine serum albumin, followed by adding a certain amount of silver nitrate solution and then directly hydrothermal treatment, a special dandelion-like g-C3N4/Ag (D-g-C3N4/Ag) was prepared. The scanning electronic microscopy, transmission electronic microscopy, X-ray diffraction, Fourier transform infrared, fluorescence and physicochemical adsorption methods were used to characterize the morphology and structure of D-g-C3N4/Ag. In addition, the photocatalytic H2 production of D-g-C3N4/Ag with different Ag loadings or in different sacrificial agents and different pH conditions were investigated. The results indicated that when triethanolamine was used as sacrificial agent, photocatalytic hydrogen efficiency was the best, and the rate of photocatalytic hydrogen production reached 862 μmol g−1 h− 1 as the Ag loading was 4%. 相似文献
49.
Deception is a complex cognition process which involves activities in different brain regions. However, most of the ERP based lie detection systems focus on the features of ERPs from few channels. In this study, we designed a multi-channel ERP based brain computer interface (BCI) system for lie detection. Based on this, two new EEG feature selection approaches, bootstrapped geometric difference (BGD) and network analysis were proposed and applied to feature recognition and classification system. Unlike other methods, our approaches focus on the changes of EEGs from different brain regions and the correlation between them. For the test, we focus on visual and auditory stimuli, two groups of subjects went through the test and their EEGs were recorded. For all subjects, BGD of the P300 for all the scalp electrodes combined with SVM classifier showed the average rate of recognition accuracy was 84.4% and 82.2% for visual and auditory modality respectively. Statistical analysis of network features indicated the difference in the two groups were significant and the average accuracy rate reached 88.7% and 83.5% respectively, and the guilty group showed more obvious small-world property than innocent group. The results suggest the BGD and network analysis based approaches combined with SVM are efficient for ERP based expert and intelligent system for detection and evaluation of deception. The combination of these methods and other feature selection approaches can promote the development and application of ERP based lie detection system. 相似文献
50.
《电子学报:英文版》2017,(5):933-941
Cut-and-choose paradigm makes Yao's protocol for two-party computation secure in malicious model with an error probability.In CRYPTO 2013,based on multi-phase cut-and-choose,Lindell reduced this probability to the optimal value.However,this work can only compute single-output functions with optimal error probability.We transform multi-phase cut-and-choose for singleoutput case into one that can deal with two-output functions,meanwhile maintaining the optimal error probability.Based on this new paradigm,we propose an efficient two-output secure computation protocol.Besides,by utilizing the specific property of the output garbled keys,we solve the authenticity issue of the generator's output with only symmetric cryptographic operations linear in the output length of the generator,which is the most efficient method so far in standard model without Random oracle (Ro). 相似文献