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排序方式： 共有690条查询结果，搜索用时 15 毫秒
681.
Abstract The Shewhart control chart was first to monitor an ongoing process and raise an alarm when it appears that the level has changed. We show that the Shewhart chart is optimal for the criterion of maximizing the probability of detecting a change upon its occurrence subject to an average run length to false alarm. It is remarkable, particularly when the change is of moderate size, that Shewhart's procedure is better than cumulative sum (CUSUM). In the multivariate setting, applying the Shewhart procedure to each process separately is suboptimal. We create a generalized Shewhart procedure that is optimal for the aforementioned criterion. The results are illustrated in common settings. 相似文献
682.
Krishna K. Yadav Dror Shamir Haya Kornweitz Yael Peled Moshe Zohar Ariela Burg 《Small Methods》2024,8(3):2301118
Dip-pen nanolithography (DPN) is a powerful and unique technique for precisely depositing tiny nano-spherical cap shapes (nanoclusters) onto a desired surface. In this study, a meta-chemical surface (MCS; a pattern with advanced features) is developed by DPN and applied to electrochemical lead sensing, yielding a calibration curve in the ppb range. An ink mixture of PMMA and NTPH (which binds to Pb (II), as supported by DFT calculations) is patterned over a Pt surface. The average height of the nanoclusters is ≈13 nm with a high surface area-to-volume ratio, which depends on the ink composition and the MCS surface. This ratio affected the sensitivity of the MCS as a detecting tool. The results indicate that the sensor's features can be controlled by the ability to control the size of the nanoclusters, attributed to the unique properties of the DPN production method. These results are significant for the water-source purification industry. 相似文献
683.
Javier A. Dávila Moshe Rosenberg Carlos A. Cardona 《American Institute of Chemical Engineers》2019,65(8):e16609
This research describes an enhance-fluidity liquid extraction process for extracting total phenolic compounds (TPC) from spent blackberry pulp (SBP) using a modified solvent (CO2–ethanol mixture). Effects of particle size (from 1,400 to 180 μm), pressure (150–300 bar), and cosolvent (ethanol)-to-solid ratio (64, 128, and 192 mL ethanol/32 g solid) on the extraction of TPC at 40°C were investigated. Experimental data was processed using the Sovova's model to obtain the solubility of TPC in the modified solvent. The Peng–Robinson equation of state was used to correlate the solubility of phenolic compounds at high pressures. Results indicated that particle sizes ranging from 600 to 850 μm and pressure of 300 bar allowed obtaining extracts with higher antioxidant activity (94.71% of inhibition) and TPC content (11.59 mg GA/g SBP). High pressure and the modified solvent increased the solubility up to 3.4 × 10−4 (mol fraction). 相似文献
684.
We classify the dynamic patterns that emerge in charging or discharging of Li-ion batteries, under galvanostatic conditions, using simulations of the two-phase one-dimensional (1D) porous electrode model. This work examines the effect of the exchange current function, R0(X), which expresses the nature of kinetics. This extends our previous study with R0 = 1 where the same pattern emerges in charging or discharging, whether as a homogeneous or a step-wise process made of multiple symmetry breaking events. With commonly-used asymmetric R0(X), the emerging patterns may be one of the two above or as fronts that follow single SB event and the lithiation/delithiation behaviors are different. These effects are clear when parameters are uniform; nonuniformity leads to noise that mask the behavior. The full four-variable model exhibits SB, even in absence of noise, since the liquid potential gradient () works like a perturbation. This similarity allows us to derive approximations to the full model behavior. 相似文献
685.
Aoibheann M. McMorrow Ruth M. Connaughton Tiago R. Magalhães Fiona C. McGillicuddy Maria F. Hughes David Cheishvili Melissa J. Morine Sean Ennis Marie‐Louise Healy Edna F. Roche Richard E. Tremblay Moshe Szyf Fiona E. Lithander Helen M. Roche 《Molecular nutrition & food research》2018,62(10)
1 Scope
Chronic inflammation and hypoadiponectinemia are characteristics of obesity‐induced insulin resistance (IR). The effect of an anti‐inflammatory nutrition supplement (AINS) on IR and adiponectin biology in overweight adolescents was investigated. The secondary objective was to examine the extent to which individuals’ biomarker profiles, derived from baseline phenotypes, predicted response or not to the AINS. Additionally, the impact of DNA methylation on intervention efficacy was assessed.2 Methods and results
Seventy overweight adolescents (13–18 years) were recruited to this randomized controlled crossover trial. Participants received an AINS (long chain n‐3 PUFA, vitamin C, α‐tocopherol, green tea extract, and lycopene) and placebo for 8 weeks each. Homeostatic model assessment (HOMA)‐IR, adiponectin, inflammatory profiles, and DNA methylation were assessed. HOMA‐IR was unchanged in the total cohort. High‐molecular‐weight (HMW) adiponectin was maintained following the AINS while it decreased over time following the placebo intervention. HOMA‐IR decreased in 40% of subjects (responders) following the AINS. Responders’ pretreatment phenotype was characterized by higher HOMA‐IR, total and LDL cholesterol, but similar BMI in comparison to nonresponders. HMW adiponectin response to the AINS was associated with bidirectional modulation of adipogenic gene methylation.3 Conclusion
The AINS modulated adiponectin biology, an early predictor of type 2 diabetes risk, was associated with bidirectional modulation of adipogenic gene methylation in weight‐stable overweight adolescents. HOMA‐IR decreased in a sub‐cohort of adolescents with an adverse metabolic phenotype. Thus, suggesting that more stratified or personalized nutrition approaches may enhance efficacy of dietary interventions. 相似文献686.
David Rand Marie Jakešová Gur Lubin Ieva Vėbraitė Moshe David‐Pur Vedran Đerek Tobias Cramer Niyazi Serdar Sariciftci Yael Hanein Eric Daniel Głowacki 《Advanced materials (Deerfield Beach, Fla.)》2018,30(25)
An efficient nanoscale semiconducting optoelectronic system is reported, which is optimized for neuronal stimulation: the organic electrolytic photocapacitor. The devices comprise a thin (80 nm) trilayer of metal and p–n semiconducting organic nanocrystals. When illuminated in physiological solution, these metal–semiconductor devices charge up, transducing light pulses into localized displacement currents that are strong enough to electrically stimulate neurons with safe light intensities. The devices are freestanding, requiring no wiring or external bias, and are stable in physiological conditions. The semiconductor layers are made using ubiquitous and nontoxic commercial pigments via simple and scalable deposition techniques. It is described how, in physiological media, photovoltage and charging behavior depend on device geometry. To test cell viability and capability of neural stimulation, photostimulation of primary neurons cultured for three weeks on photocapacitor films is shown. Finally, the efficacy of the device is demonstrated by achieving direct optoelectronic stimulation of light‐insensitive retinas, proving the potential of this device platform for retinal implant technologies and for stimulation of electrogenic tissues in general. These results substantiate the conclusion that these devices are the first non‐Si optoelectronic platform capable of sufficiently large photovoltages and displacement currents to enable true capacitive stimulation of excitable cells. 相似文献
687.
688.
689.
Moshe Averbukh Simon Lineykin Alon Kuperman 《Progress in Photovoltaics: Research and Applications》2013,21(5):1016-1024
The paper presents a simple approach to deriving I–V curves of photovoltaic panels and small arrays for arbitrary environmental conditions on the basis of three points of a single operating curve data and short current temperature coefficient only. The proposed method does not employ fitting of any type and is solely based on a numerical solution of a system of transcendental equations. The equations are expressed in a dimensionless form, simplifying both the solution and photovoltaic panel parameters' representation. The solution is used to find the values of normalized equivalent circuit elements for the available data and then perform an appropriate adjustment to obtain the operating curves for arbitrary conditions. The proposed method was applied to monocrystalline and polycrystalline commercial solar panels and was compared with both manufacturer‐provided and experimentally measured operating curves to analyze the approach applicability and accuracy. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
690.
The present research focuses on a model system of a blend of two immiscible polymers containing an inorganic nanofiller, exploring the effect of various melt processing procedures on structuring and on the resulting properties. Binary polypropylene/alumina and ternary polypropylene/nylon/alumina composites were produced by batch compounding under various processing conditions and compositions. Several types of polypropylene and alumina grades were examined. The alumina nanoparticles vary primarily in their mean particle size (13, 50, 500 nm). The morphology of the nanocomposites produced and their thermal, and rheological properties were studied. It was found that under certain processing conditions the nanoparticles significantly affect the morphology of the polypropylene/nylon polymer blend causing compatibilization. Also, the alumina nanoparticles affect the melt viscosity of the polypropylene/nylon blends, whereas their effect on either polypropylene or nylon melts was found insignificant. POLYM. COMPOS., 27:425–430, 2006. © 2006 Society of Plastics Engineers 相似文献