Experimental and Sensitivity Analysis of DMASP Cantilever Vibration Behavior Based on MCS Theory in the Moist Environment

A Micro-cantilever (MC) and a probe are two main components of the atomic force microscope (AFM). The dimensions of these components are in micro scales while their oscillation amplitude is on a nanometer scale. The present study intended to not only increase the accuracy of the simulation with regard to geometric discontinuities based on the Timoshenko Beam Model using the modified couple stress (MCS) theory but also increase the accuracy of the prediction of a system behavior by considering the effect hysteresis effect into the system vibration equations based on Bouc-Wen Model. Due to the lack of the experimental results for this kind of MCs, this paper is focused on the both experiment and simulation results by utilizing the DMASP micro cantilever. The vibration equations have been discretized based on the differential quadrature (DQ) model and solved using the Newmark algorithm and Laplace transforms in the free and forced vibration modes of AFM piezoelectric MC. The roughness of the surfaces affects the MC vibration behavior in the air medium. Therefore, surface roughness affecting van der Waals force has been considered in the air medium. Furthermore, the simulation results were compared with experimental results by performing experimental tests in the air medium with different moisture content. The experimental tests performed in the free vibration mode included frequency and time response and the forced mode sample surface topography and its effect on the MC vibration amplitude during the sample surface topography in different vibration modes. Moreover, the speed of equation solving was accelerated by performing sensitivity analysis based on the EFAST method as well as investigating the coupling effect of geometric and enforcement parameters on the amplitude and frequency of the MC and eliminating less effective parameters. The comparison of experimental results with theoretical results is indicative of the accuracy of MCS theory in the simulation

Sensitivity Analysis of Coulomb and HK Friction Models in 2D AFM-Based Nano-Manipulation: Sobol Method

Abstract: Nanotechnolog

Management of Chronic Myeloid Leukemia with Sever COVID 19: A Case Report

Coronavirus disease-19 (COVID-19) is a pandemic viral disease that can cause devastating complications such as acute respiratory disease, especially in patients with comorbidities. We do not know yet full pictures of this disease, especially in hematological malignancies. Here, we present management of a 57-year-old male with chronic phase chronic myeloid leukemia, tested positive for COVID-19, then complicated with acute respiratory distress syndrome

Efficacy of Zinc Foliar Application from Different Sources on Productivity and Fruit Quality of Wonderful Pomegranate trees

Nanoparticles (NPs), especially from micronutrients, are recently motivated for replacing their common mineral counterparts. To evaluate their comparative efficacy, this investigation was conducted to estimate the impact of foliar application of zinc through different sources on productivity, fruit quality and improve marketable fruit of “Wonderful” pomegranate trees. The field experiment was performed during two seasons (2017 and 2018) on seven - year old pomegranate trees “Wonderful” cv., cultivated in a private “Hegazi” farm located at 57 km. from Cairo on the road to Alex., Egypt. Four sources of zinc named “Zinc Sulphate, Zinc mannitol complex, Bio-Nano zinc (Bio Zn NPs) and Zinc Oxide nanoparticle (ZnO NPs) with four rates from each other were sprayed twice (the first before one week from full bloom and the second after a month from the first). So the experiment included seventeen treatments in a sample study spread in a randomized complete block design by five replicates. Results explicated that the greatest significant values of fruit set% were recorded by Bio Nano Zinc (Bio Zn NPs) treatments especially (400 ppm Bio-Nano Zinc (Bio Zn NPs)). Spraying with (3000, 4000 ppm Zn mannitol complex) and (300, 400 ppm Bio-Nano Zinc (Bio Zn NPs)) showed significantly the greatest values of productivity, improves marketable fruits and fruit quality of “Wonderful” pomegranate trees. So it could be recommended by spraying “Wonderful” pomegranate trees by 3000 ppm Zinc mannitol complex or 300 ppm Bio-Nano zinc (Bio Zn NPs). Another important point is that the application of Bio Zn NPs fertilizer at around 10% from the commercial dose of zinc sulphate resulted in the same results without any change in the productivity, further researches are needed to study a further low level of Zinc Oxide nanoparticle (ZnO NPs) below (100 ppm Zinc Oxide nanoparticle (ZnO NPs)) which may be improving yield and fruit qualit

Experimental investigation of sandy soil stabilization using chitosan biopolymer

The performance of an environmentally friendly biopolymer synthesised from secondary resources to overcome the wind erosion of sandy soil was investigated in this study. The study employed a multi-scale approach to investigate the mechanical, erosional, and hydraulic properties of sandy soil. At the macroscale, experimental techniques such as unconfined and triaxial compression tests, permeability measurements, contact angle assessments, and wind tunnel experiments were utilized to characterize the bulk behavior of the soil. Concurrently, molecular dynamics (MD) simulations were conducted at the nanoscale to predict surface mechanical characteristics and elucidate chemical interactions at the molecular level. Results show that when the outer surface of the sandy particles is coated with a sparse concentration of biopolymer, the sandy aerosol inhibitory performance is significant even under extreme storm conditions reaching speeds of 140 km/h of storms. The study on the impact of biopolymer content, curing time, and curing conditions revealed that the addition of chitosan biopolymer has the ability to enhance the bonding between particles and significantly enhance the mechanical properties of sandy soil. The atomic insight from molecular dynamics reveals huge entanglement between sandy particles and biopolymer by Van der Waals interaction. The results of the Unconfined Compressive Strength test indicate that chitosan enhances the compressive strength of sand by up to 320 kPa. Additionally, the triaxial test demonstrated that the application of chitosan led to a 34.2 kPa improvement in the cohesion of sand. Furthermore, analysis of the permeability test results revealed a decrease in the hydraulic conductivity coefficient from 1.6 × 10^-6 m/s to 5.7 × 10^-7 m/s, representing a reduction of approximately 35 %

Incorporation of Natural Lithium-Ion Trappers into Graphene Oxide Nanosheets

© 2020 Wiley-VCH GmbH Lithium consumption is estimated to face a considerable rise in the next decade; thus, finding new reproducible lithium resources such as brine deposits and seawater has become a fast-growing research topic. However, Li+ extraction from these resources is challenging due to its low concentration and presence of other monovalent cations exhibiting identical chemical properties. Here, it is discovered that tannic acid (TA) inside graphene oxide (GO) nanochannel acts as natural ion trapper, which possesses lithiophilic elements. The lithium-rich feed is achieved by using the potential-driven TA-GO membrane by excluding lithium ions from other monovalent cations. The results showed that the ion trapping capability of inexpensive TA-GO membrane is Li+ > Na+ > K+ with Li trapping energy of −593 KJ mol−1, respectively, where its trapping efficiency goes into a top rank among their expensive synthetic counterparts. Evaluating the combined effect of three key parameters, including barrier energy, hydration energy, and binding energy illustrates that required energy to transport Li-ion through the membrane is higher than that for other monovalent. This proof-of-concept work opens up an avenue of research for designing a new class of ion-selective membranes, based on the incorporation of naturally low cost available lithiophilic guest molecules into 2D membranes

Reformism, Economic Liberalisation and Popular Mobilisation in Iran

Whereas in other MENA countries the impact of neo-liberal policies has been the subject of intense debate, there are at present few voices that directly analyse or critique its social and political consequences in Iran. This article seeks to address this lacuna by analysing the dynamics of reformism, economic liberalisation and popular mobilisation in Iran. It charts the country’s move from a post-revolutionary populism to a liberalised yet increasingly exclusivist model of politics and compares this to trajectories of economic liberalisation in Egypt. Two distinct outcomes of economic reform are analysed in the first part of the article: Socio-economic exclusion; and the contraction of political rights. In the second half, I investigate the ways successive post-war governments in Iran have packaged neo-liberal reforms, and how their re-imagining of the role of the state has led to differing levels of popular resistance. Finally I argue that under the present administration, political elites increasingly are oriented toward strengthening the state and seeking to limit opposition to their policies. However, the absence of neo-liberal hegemony in Iran means that growing mobilization on socio-economic issues is challenging these policies. The Right in Iranian politics is utilizing this mobilisation to present a populist challenge to the reformists in power

A Potential Role for Drosophila Mucins in Development and Physiology

Vital vertebrate organs are protected from the external environment by a barrier that to a large extent consists of mucins. These proteins are characterized by poorly conserved repeated sequences that are rich in prolines and potentially glycosylated threonines and serines (PTS). We have now used the characteristics of the PTS repeat domain to identify Drosophila mucins in a simple bioinformatics approach. Searching the predicted protein database for proteins with at least 4 repeats and a high ST content, more than 30 mucin-like proteins were identified, ranging from 300–23000 amino acids in length. We find that Drosophila mucins are present at all stages of the fly life cycle, and that their transcripts localize to selective organs analogous to sites of vertebrate mucin expression. The results could allow for addressing basic questions about human mucin-related diseases in this model system. Additionally, many of the mucins are expressed in selective tissues during embryogenesis, thus revealing new potential functions for mucins as apical matrix components during organ morphogenesis