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1.
The increasing use of nanoparticles and their occurrence in the environment has made it imperative to elucidate their impact on the environment. Although several studies have advanced the authors’ understanding of nanoparticle–plant interactions, their knowledge of the exposure of plants to nanoparticles and their effects on edible crop plants remain meager and is often paradoxical. The aim of this study was to increase their knowledge on the effect of zinc oxide (ZnO) nanoparticles on eggplant seed germination and seedling growth. ZnO nanoparticles had a negative effect on the growth of eggplant in plant tissue‐culture conditions, as the growth of seedlings decreased with the increase in the concentration of ZnO nanoparticles. In contrast, ZnO nanoparticles enhanced eggplant growth under greenhouse conditions. The accumulation of ZnO nanoparticles in various parts of eggplant was observed through scanning electron microscopy of both plant tissue‐culture and greenhouse‐raised eggplant seedlings. To the best of their knowledge, this is the first study to report on ZnO nanoparticle accumulation in eggplant and its effect on seed germination and seedling growth.Inspec keywords: crops, zinc compounds, scanning electron microscopy, II‐VI semiconductors, nanoparticles, agriculture, cellular biophysics, nanofabricationOther keywords: plant tissue‐culture, greenhouse‐raised eggplant seedlings, ZnO nanoparticle accumulation, seedling growth, ZnO nanoparticles, nanoparticle–plant interactions, zinc oxide nanoparticles, eggplant seed germination, eggplant growth, ZnO  相似文献   
2.
Planar electrolyte supported solid oxide fuel cells were operated at 900 °C with humidified H2 for 200 h using silver mesh and paste for cathode current collection. Continuous potentiostatic tests at 0.7 V appeared to induce migration of Ag towards electrode-electrolyte interphase, while continuous OCV tests caused no mass transport. Similar SOFCs fueled by coal syngas at 850 °C using Ag for both anode and cathode current collection indicated little, if any, Ag migration; providing the possibility of employing Ag for 100 h laboratory scale tests using coal-derived syngas. Use of high temperature steam, carbon dioxide and carbon monoxide did not result in the formation of silver carbonates.  相似文献   
3.
Cost-effective catalysts for hydrogen evolution reaction (HER) are attractive for sustainable production of H2 fuel. Herein, a series of tunable Ni/Fe-Mo carbide catalysts have been synthesized via a sol-gel method coupling with a subsequent high temperature carbonization process. The amount of nickel and iron was tuned in the Mo7/C precursors, accomplishing a favourable performance of noble-metal-free electrocatalysts for HER. As expected, the designed Ni10Fe4Mo7/C catalyst displays an enhanced catalytic activity toward hydrogen production with an ultralow overpotential (η10 = 110 mV) and striking kinetics (ηonset = 58 mV, k = 54 mV · dec−1) in the alkaline electrolyte (1 M KOH), which are comparable to those of the commercial 20% Pt/C catalyst. Such excellent performance of Ni10Fe4Mo7/C could be attributed to the high intrinsic activities of Ni-based alloys (NiMo4) and Mo2C, as well as to the lattice contraction in the Mo2C unit cell, in accordance with its high electrochemical surface area (~133 m2 · g−1) and low charge-transfer resistance (~31.5 Ω) for the associated electrode.  相似文献   
4.
OBJECTIVE: To investigate the associations of individual and area-based socioeconomic indicators with cardiovascular disease risk factors and mortality. DESIGN: Prospective study. SETTING: The towns of Renfrew and Paisley in the west of Scotland. PARTICIPANTS: 6961 men and 7991 women included in a population-based cardiovascular disease screening study between 1972 and 1976. MAIN OUTCOME MEASURES: Cardiovascular disease risk factors and cardiorespiratory morbidity at the time of screening: 15 year mortality from all causes and cardiovascular disease. RESULTS: Both the area-based deprivation indicator and individual social class were associated with generally less favourable profiles of cardiovascular disease risk factors at the time of the baseline screening examinations. The exception was plasma cholesterol concentration, which was lower for men and women in manual social class groups. Independent contributions of area-based deprivation and individual social class were generally seen with respect to risk factors and morbidity. All cause and cardiovascular disease mortality rates were both inversely associated with socioeconomic position whether indexed by area-based deprivation or social class. The area-based and individual socioeconomic indicators made independent contributions to mortality risk. CONCLUSIONS: Individually assigned and area-based socioeconomic indicators make independent contributions to several important health outcomes. The degree of inequalities in health that exist will not be demonstrated in studies using only one category of indicator. Similarly, adjustment for confounding by socioeconomic position in aetiological epidemiological studies will be inadequate if only one level of indicator is used. Policies aimed at reducing socioeconomic differentials in health should pay attention to the characteristics of the areas in which people live as well as the characteristics of the people who live in these areas.  相似文献   
5.
以高温氧化性炉渣为电解质,工业MgO-C砖为阴极,钼丝为阳极,研究外电场作用下耐火材料在CaO-SiO^2-FeO三元氧化性渣中的侵蚀行为。结果表明:在CaO-SiO2-FeO渣中,Si的还原电位约为-5.85V,Fe的还原电位约为-1.25V;当外加电压小于炉渣中离子还原电位时,电压趋使炉渣中离子(Fe^2+,Ca^2+)向阴极作定向移动,而SiO4^2-由于离子半径大,移动速度较慢,大部分滞留在阴极区域,使得阴极附近熔渣粘度不断增加,有效降低了炉渣渗透深度;当阴极电位低于炉渣中离子还原电位时,炉渣中Fe^2+和SiO4^2-将发生电化学还原,Fe和Si的析出促使熔渣组成发生变化,诱导高熔点相硅酸二钙沉积层的形成。高熔点沉积层有效阻断炉渣与耐火材料直接接触,使得熔渣在耐火材料中的渗透深度显著降低,提高了耐火材料抗渣侵能力。  相似文献   
6.
The recent increase in the use of speed control of ac induction motor for variable speed drive using pulse width modulation (PWM) inverter is due to the advent of modern power electronic devices and introduction of microprocessors. There are many advantages of using ac induction motor for speed control applications in process and aerospace industries, but due to fast switching of the modern power electronic devices, the parasitic coupling produces undesirable effects. The undesirable effects include radiated and conducted electromagnetic interference (EMI) which adversely affect nearby computers, electronic/electrical instruments and give rise to the flow of bearing current in the induction motor. Due to the flow of bearing current in the induction motor, electrical discharge machining takes place in the inner race of the bearing which reduces the life of the bearing. In high power converters and inverters, the conducted and radiated emissions become a major concern. In this paper, identification of bearing current due to conducted emission, the measurement of bearing current in a modified induction motor and to minimize the bearing current are discussed. The standard current probe, the standard line impedance stabilization network (LISN)), the electronics interface circuits are used to measure high frequency common mode current, bearing current and to minimize the conducted noise from the system. The LISN will prevent the EMI noise entering the system from the supply source by conductive methods, at the same time prevents the EMI generated if any due to PWM, fast switching in the system, will not be allowed to enter the supply line. For comparing the results with Federal Communications Commission (FCC) and Special Committee on Radio Interference (CISPR) standards, the graphs are plotted with frequency Vs, line voltage in dBμ V, common mode voltage in dBμ V and the bearing current in dBμ A with out and with minimizing circuits.  相似文献   
7.
Nowadays, underwater wireless sensor network (UWSN) is an important field for researchers due to its well know applications like seismic monitoring, disaster prevention, offshore exploration, pollution monitoring, oceanography data collection, equipment monitoring, assisted navigation, and tactical surveillance. Many research challenges are available for UWSN; the design of routing protocol is one of them. The majority of the researchers have designed the routing algorithms but still, the data forwarding mechanism needs improvement. The reliable communication between the source and sink nodes is really a complicated task due to the limitation of the acoustic channel, water pressure, and limited bandwidth. This review paper focuses on the problems of those routing protocols which are based on data forwarding. In this review paper, we further present the route development, data forwarding, and route maintenance of the proposed routing protocols. The key aspects of this review article present the limitations and advantages of data forwarding routing protocols. We also present analysis of data forwarding routing protocols with analytical and numerical simulation methods with their critical analysis. This review article helps the researchers to create further research in the field of routing protocols based on data forwarding.  相似文献   
8.
Lined pipe girth weld regions are challenging to inspect using ultrasonic techniques due to their anisotropic and inhomogeneous characteristics, which lead to noise and acoustic beam distortion. This paper is focused on the application of coherence weighting methods to decrease the background noise level and false indications on total focusing method (TFM) images, encompassing the triple boundary of mechanically lined pipes. Three coherence weighting approaches were used here; the coherence factor (CF), the sign CF (SCF) and the phase CF (PCF). All three were found capable to improve the TFM images, however, the CF and the SCF performed better due to their exponential sensitivity factors, unlike the PCF which has a linear sensitivity factor.  相似文献   
9.
Wei  Peipei  Geng  Qin  Channa  Ali Imran  Tong  Xin  Luo  Yongsong  Lu  Siyu  Chen  Guang  Gao  Shuyan  Wang  Zhiming  Sun  Xuping 《Nano Research》2020,13(11):2967-2972

To develop highly efficient electrochemical catalysts for N2 fixation is important to sustainable ambient NH3 production through the N2 reduction reaction (NRR). Herein, we demonstrate the development of vanadium phosphide nanoparticle on V foil as a high-efficiency and stable catalyst for ambient NH3 production with excellent selectivity. The high Faradaic efficiency of 22% with a large NH3 yield of 8.35 × 10−11 mol·s−1·cm−2 was obtained at 0 V vs. the reversible hydrogen electrode in acid solution, superior to all previously studied V-based NRR catalysts. Density functional theory calculations are also utilized to have an insight into the catalytic mechanism.

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10.
PSP data processing, which primarily involves image alignment and image analysis, is a crucial element in obtaining accurate PSP results. There are two broad approaches to image alignment: the algebraic transformation technique, often called image-warping technique, and resection methodology, which uses principles of optical photogrammetry. Resection is found to have higher resolution, especially when large gradients in pressure or significantly three-dimensional regions have to be resolved, and even with flat models when the camera angles are large. A processing software based on these methodologies has been successfully developed and validated and is currently in use at the Experimental Aerodynamics Division of the National Aerospace laboratories, Bangalore. In this paper, we show the merits of resection methodology through two examples: (a) a wing-body model in transonic flow (M = 0.8) and (b) a simple delta wing in low supersonic flow (M = 1.8). The PSP system utilized for both the cases involve Optrod-B1 paint, a specially designed UV lamp for excitation and two scientific grade CCD cameras for imaging. Typical results are shown using both the algebraic transformation approach and resection methodology.  相似文献   
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