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121.
Ayelet Vilan Omer Yaffe Ariel Biller Adi Salomon Antoine Kahn David Cahen 《Advanced materials (Deerfield Beach, Fla.)》2010,22(2):140-159
Basic scientific interest in using a semiconducting electrode in molecule‐based electronics arises from the rich electrostatic landscape presented by semiconductor interfaces. Technological interest rests on the promise that combining existing semiconductor (primarily Si) electronics with (mostly organic) molecules will result in a whole that is larger than the sum of its parts. Such a hybrid approach appears presently particularly relevant for sensors and photovoltaics. Semiconductors, especially Si, present an important experimental test‐bed for assessing electronic transport behavior of molecules, because they allow varying the critical interface energetics without, to a first approximation, altering the interfacial chemistry. To investigate semiconductor‐molecule electronics we need reproducible, high‐yield preparations of samples that allow reliable and reproducible data collection. Only in that way can we explore how the molecule/electrode interfaces affect or even dictate charge transport, which may then provide a basis for models with predictive power. To consider these issues and questions we will, in this Progress Report,
- review junctions based on direct bonding of molecules to oxide‐free Si.
- describe the possible charge transport mechanisms across such interfaces and evaluate in how far they can be quantified.
- investigate to what extent imperfections in the monolayer are important for transport across the monolayer.
- revisit the concept of energy levels in such hybrid systems.
122.
Adi Arieli 《Journal of Materials Science》1981,16(10):2760-2766
This paper considers to what extent the second-phase volume fraction in superplastic binary alloys affect the matrix grain
size stability during deformation and, through it, the flow stress at constant temperature and strain rate. It is shown for
five different superplastic binary alloy systems, that at constant temperature and strain rate the flow stress will increase
with the deviation of the second-phase volume fraction in the alloys from that required for maximum matrix grain size stability.
A new parameter (Z) which quantifies these deviations has been introduced in this paper. The possible errors in determining
the pertinent parameters in the rate equation for superplastic flow by testing alloys withZ is discussed. 相似文献
123.
Approximating MIN 2-SAT and MIN 3-SAT 总被引:1,自引:0,他引:1
We obtain substantially improved approximation algorithms for the MIN k-SAT problem, for k = 2,3. More specifically, we obtain a 1.1037-approximation algorithm for the MIN 2-SAT problem, improving a previous 1.5-approximation algorithm, and a 1.2136-approximation algorithm for the MIN 3-SAT problem, improving a previous 1.75-approximation algorithm for the problem. These results are obtained by adapting techniques that were previously used to obtain approximation algorithms for the MAX k-SAT problem. We also obtain some hardness of approximation
results. 相似文献
124.
A cryptographic protocol is a distributed program that can be executed by several actors. Since several runs of the protocol within the same execution are allowed, models of cryptoprotocols are often infinite. Sometimes, for verification purposes, only a finite and approximated model is needed. For this, we consider the problem of computing such an approximation and we propose to simulate the required partial execution in an abstract level. More precisely, we define an abstract finite category G a as an abstract game semantics for the SPC calculus, a dedicated calculus for security protocols. The abstract semantics is then used to build a decision procedure for secrecy correctness in security protocols. 相似文献
125.
Hossein Hamidi Erfan Mohammadian Amin Sharifi Hadd Roozbeh Rafati Amin Azdarpour Panteha Ghahri Adi Putra Pradan Bastian Andoni Chingis Akhmetov 《石油科学(英文版)》2017,14(3):597-604
The adverse impacts of CO2 emission on the global warming highlight the importance of carbon capture and storage technology and geological storage of CO2 under solubility trapping mechanisms. Enhancing the solubility of CO2 in formation water has always been the focus of research in the area of CO2 sequestration. Ultrasound techniques are one of the environmentally friendly methods that use high-intensity acoustic waves to improve gas solubility in liquids. Ultrasonic waves can alter the properties of different phases that lead to chemical reactions and provide a means to increase the solubility of CO2 in connate water. In this study, we investigated the effects of ultrasound on the solubility of CO2 in connate water under different conditions of pressure, temperature, and salinity. The results showed that the solubility of CO2 was improved with increasing pressure under ultrasonic effects. However, the solubility of CO2 was inversely proportional to the increase in brine salinity and temperature. Therefore, it was concluded that the solubility of CO2 might be enhanced in the presence of ultrasound. 相似文献
126.
Damon J. A. Toth Molly Leecaster Warren B. P. Pettey Adi V. Gundlapalli Hongjiang Gao Jeanette J. Rainey Amra Uzicanin Matthew H. Samore 《Journal of the Royal Society Interface》2015,12(108)
Influenza poses a significant health threat to children, and schools may play a critical role in community outbreaks. Mathematical outbreak models require assumptions about contact rates and patterns among students, but the level of temporal granularity required to produce reliable results is unclear. We collected objective contact data from students aged 5–14 at an elementary school and middle school in the state of Utah, USA, and paired those data with a novel, data-based model of influenza transmission in schools. Our simulations produced within-school transmission averages consistent with published estimates. We compared simulated outbreaks over the full resolution dynamic network with simulations on networks with averaged representations of contact timing and duration. For both schools, averaging the timing of contacts over one or two school days caused average outbreak sizes to increase by 1–8%. Averaging both contact timing and pairwise contact durations caused average outbreak sizes to increase by 10% at the middle school and 72% at the elementary school. Averaging contact durations separately across within-class and between-class contacts reduced the increase for the elementary school to 5%. Thus, the effect of ignoring details about contact timing and duration in school contact networks on outbreak size modelling can vary across different schools. 相似文献
127.
Shir Confino Talya Dor Adi Tovin Yair Wexler Zohar Ben-Moshe Livne Michaela Kolker Odelia Pisanty Sohyun Kathy Park Nathalie Geyer Joel Reiter Shimon Edvardson Hagar Mor-Shaked Orly Elpeleg Daniela Vallone Lior Appelbaum Nicholas S. Foulkes Yoav Gothilf 《International journal of molecular sciences》2022,23(4)
The circadian clock, which drives a wide range of bodily rhythms in synchrony with the day–night cycle, is based on a molecular oscillator that ticks with a period of approximately 24 h. Timed proteasomal degradation of clock components is central to the fine-tuning of the oscillator’s period. FBXL3 is a protein that functions as a substrate-recognition factor in the E3 ubiquitin ligase complex, and was originally shown in mice to mediate degradation of CRY proteins and thus contribute to the mammalian circadian clock mechanism. By exome sequencing, we have identified a FBXL3 mutation in patients with syndromic developmental delay accompanied by morphological abnormalities and intellectual disability, albeit with a normal sleep pattern. We have investigated the function of FBXL3 in the zebrafish, an excellent model to study both vertebrate development and circadian clock function and, like humans, a diurnal species. Loss of fbxl3a function in zebrafish led to disruption of circadian rhythms of promoter activity and mRNA expression as well as locomotor activity and sleep–wake cycles. However, unlike humans, no morphological effects were evident. These findings point to an evolutionary conserved role for FBXL3 in the circadian clock system across vertebrates and to the acquisition of developmental roles in humans. 相似文献
128.
Benjaram M. Reddy Pankaj Bharali Yeong-Hui Seo Eko Adi Prasetyanto Sang-Eon Park 《Catalysis Letters》2008,126(1-2):125-133
Uniform nanosized, mesoporous and high specific surface area ceria–zirconia (1:1 mole ratio) solid solutions were synthesized employing a poly-block copolymer surfactant combined with microwave or thermal treatment. For comparison purpose an identical composition Ce x Zr1?x O2 mixed oxide was also prepared by a conventional coprecipitation method. The surface and bulk structure of the synthesized samples were investigated using X-ray diffraction (XRD), small angle X-ray scattering (SAXS), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET surface area and BJH pore size distribution (PSD) methods. The catalytic activity was evaluated for CO oxidation at normal atmospheric pressure. The Ce x Zr1?x O2 solid solutions obtained through surfactant use exhibited high specific surface area and mesoporosity. The XRD measurements revealed the presence of cubic Ce0.75Zr0.25O2 and Ce0.6Zr0.4O2 phases in the case of conventional coprecipitation and surfactant controlled synthesized samples, respectively. The Raman measurements revealed existence of more oxygen defects in the surfactant-controlled and microwave treated sample. The SEM images suggested that all samples consist of typical spherical agglomerates with almost uniform size within the nanometer size range. The TEM measurements revealed nanosized crystallites in a narrow range between 4 and 8 nm, and densely packed in the case of conventional precipitation and microwave treated samples. Interestingly, the Ce x Zr1?x O2 solid solution obtained by surfactant-controlled method and treated with microwave radiation exhibited better CO oxidation activity than other samples. Enhanced activity of surfactant-controlled and microwave treated sample is correlated with its unique physicochemical characteristics. 相似文献
129.
130.
In this paper, we propose a novel intrusion detection technique with a fully automatic attack signatures generation capability. The proposed approach exploits a honeypot traffic data analysis to build an attack scenarios database, used to detect potential intrusions. Furthermore, for an effective and efficient intrusion detection mechanism, we introduce several new or adapted algorithms for signature generation, signature comparison, etc. Finally, we use DARPA’99 and UNSW-NB15 traffic to evaluate the proposed approach. The results indicate that the generated attack signatures are of high quality with low rates of false negatives and false positives. 相似文献