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141.
The electrochromic response of W03 thin films under electrochemical insertion from nonaqueous electrolytes of one of the three different ions: protons, lithium and sodium cations is reported. In spite of the common belief that the nature of the ion does not change the electrochromic effect, we show that the sample colouring and bleaching are dependent on the intercalant ion and on the insertion rate. The facile insertion of protons is responsible for the highest optical contrast and the quickest response time of this intercalation electrode. Lithium and sodium-intercalated electrodes do not show large optical difference from the proton-intercalated tungsten trioxide unless large charging currents are used. Subtle changes in electrochromic efficiency and in the optical contrast in the red part of the spectrum can be detected; these are larger for the sodium than for the lithium intercalant. According to our analysis, the slow insertion kinetics of Na+ and the formation of a new M
x
WO3 (M=Li, Na) compound is responsible for most of the observed differences. 相似文献
142.
Approach for Grid Connected PV Management: Advance Solar Prediction and Enhancement of Voltage Stability Margin Using FACTS Device 下载免费PDF全文
Md. Masum Howlader Aziz Un Nur Ibn Saif MD Shahrukh Adnan Khan Mahfuj Howlader Mohammad Rokonuzzaman Md Tanbhir Hoq 《电子科技学刊:英文版》2020,18(4):367-377
The uncertainty in solar energy is different from conventional, dispatchable generation fuels and difficult to incorporate into the standard system operating procedures. In the first part of this work, the machine learning algorithm is used to train models based on solar irradiance data and different meteorological weather information to predict the solar irradiance for different cities to validate the forecasting model. Again, the intermittent and inertialess nature of photovoltaic (PV) systems can produce significant power oscillations that can cause significant problems with dynamic stability of the power system and also limit the penetration capacity of PV into the grid. In the second part, it is shown that the residue-based power oscillation damping (POD) controller obviously improves the inter-area oscillation damping. The validity and effectiveness of the proposed controller are demonstrated on the three-machine two-area test system that combines the conventional synchronous generator and flexible alternating current transmission systems (FACTS) device using simulations. This report overall puts an in-depth analysis with regard to the challenges of solar resources with integrating, planning, operating, and particularly the stability of the rest of the power grid, including existing generation resources, customer requirements, and the transmission system itself that will lead to an improved decision making in resource allocations and grid stability. 相似文献
143.
Sabuj Saifur Rahman Nur Tabassum E Hamamura Masanori 《Wireless Personal Communications》2020,114(3):1963-1981
Wireless Personal Communications - Motivated by the current demand for improvements in transmission rate and energy efficiency of random wireless cellular networks, we investigate the theoretical... 相似文献
144.
Cinzia Bernardeschi Marco Di Natale Gianluca Dini Maurizio Palmieri 《Journal in Computer Virology》2018,14(4):269-289
This paper presents an approach for enhancing the design phase of AUTOSAR models when security annotations are required. The approach is based on information flow analysis and abstract interpretation. The analysis evaluates the correctness of the model by assessing if the flow of data is secure with respect to causal data dependencies within the model. To find these dependencies an exhaustive search through the model would be required. Abstract interpretation is used as a trade-off between the precision and complexity of the analysis. The approach also provides annotated models without oversizing the set of annotations. 相似文献
145.
Gü zide alik Nur Pehl
van Nerm
Kalender Tun er H.
zdamar Pinar alik 《Chemical Engineering Communications》2003,190(5):630-644
Recombinant Bacillus amyloliquefaciens, Bacillus cereus, Bacillus subtilis , and Bacillus licheniformis were used for the production of serine alkaline protease (SAP) utilizing chemically and/or physically pretreated molasses. The highest enzyme activity was obtained with r- Bacillus subtilis , with the complex medium involving physically treated molasses having 20 kg m -3 initial sucrose concentration in small-scale, agitation- and heating rate-controlled bioreactors at t=63 h. Effects of oxygen transfer were investigated in 3.5 dm 3 laboratory bioreactors under two different agitation rates with r- B. subtilis . Increase in the oxygen transfer rate increased the observed activity and caused the cultivation time of maximum activity shift to the earlier stages of the fermentation. At Q/V=0.5 vvm and N=750 min -1 , SAP activity reached 2250U cm -3 at t=36 h. 相似文献
146.
开阳堡根据周易八卦之形而建,运用八卦、风水学,选址在一个形如龟背的沿河高地上.街区规划有别于传统的以南北中轴线为南北大街的格局,而采用南北两条较对称的大街,与东西二条街形成"井"字型结构,把整个堡划分为九部分,称"九宫街". 相似文献
147.
Perfluorinated Ionomer‐Modified Hole‐Injection Layers: Ultrahigh‐Workfunction but Nonohmic Contacts 下载免费PDF全文
Dagmawi Belaineh Jun‐Kai Tan Rui‐Qi Png Pei‐Fang Dee Yi‐Min Lee Bao‐Nguyen Nguyen Thi Nur‐Sabrina Ridzuan Peter K. H. Ho 《Advanced functional materials》2015,25(34):5504-5511
Recently it has been reported that Nafion oligomers, i.e., 2‐(2‐sulfonatotetrafluoroethoxy)‐2‐trifluoromethyltrifluoroethoxyfunctionalized oligotetrafluoroethylenes, also called perfluorinated ionomers (PFIs), can be blended into poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDT:PSSH) films to increase their workfunctions beyond 5.2 eV. These PFI‐modified films are useful for energy‐level alignment studies, and have been proposed as hole‐injection layers (HILs). It is shown here however that these HILs do not provide sufficiently fast hole transfer into adjacent polymer semiconductor layers with ionization potentials deeper than ≈5.2 eV. X‐ray and ultraviolet photoemission spectroscopies reveal that these HILs exhibit a molecularly‐thin PFI overlayer that sets up a surface dipole that provides the ultrahigh workfunction. This dipolar layer persists even when the subsequent organic semiconductor layer is deposited, as evidenced by measurements of the diode built‐in potentials. As a consequence, the PFI‐modified HILs produce a higher contact resistance, and a lower equilibrium density of holes at the semiconductor contact than might have been expected from simple thermodynamic considerations of the reduction in hole‐injection barrier. Thus the use of insulating dipolar surface layers at the charge‐injection contact to tune its workfunction to match the relevant transport level of the semiconductor is of limited utility to achieve ohmic contact in these devices. 相似文献
148.
Vishal Jhanji Mithun Santra Andri K. Riau Moira L. Geary Tianbing Yang Elizabeth Rubin Nur Zahirah Binte M. Yusoff Deepinder K. Dhaliwal Jodhbir S. Mehta Gary Hin-Fai Yam 《International journal of molecular sciences》2022,23(13)
Corneal blindness due to scarring is conventionally treated by corneal transplantation, but the shortage of donor materials has been a major issue affecting the global success of treatment. Pre-clinical and clinical studies have shown that cell-based therapies using either corneal stromal stem cells (CSSC) or corneal stromal keratocytes (CSK) suppress corneal scarring at lower levels. Further treatments or strategies are required to improve the treatment efficacy. This study examined a combined cell-based treatment using CSSC and CSK in a mouse model of anterior stromal injury. We hypothesize that the immuno-regulatory nature of CSSC is effective to control tissue inflammation and delay the onset of fibrosis, and a subsequent intrastromal CSK treatment deposited collagens and stromal specific proteoglycans to recover a native stromal matrix. Using optimized cell doses, our results showed that the effect of CSSC treatment for suppressing corneal opacities was augmented by an additional intrastromal CSK injection, resulting in better corneal clarity. These in vivo effects were substantiated by a further downregulated expression of stromal fibrosis genes and the restoration of stromal fibrillar organization and regularity. Hence, a combined treatment of CSSC and CSK could achieve a higher clinical efficacy and restore corneal transparency, when compared to a single CSSC treatment. 相似文献
149.
结合陕西地区实例,古代瓦当在现代文明中的再现,来说明瓦当文化在今日的辉煌.瓦当在现代文明中更显其艺术价值,展示出特有的生命力.它体现了传统精神与现代文明的共生性. 相似文献
150.