Sharif Digital Repository

We have developed an enhanced technique for characterizing quantum optical processes based on probing unknown quantum processes only with coherent states. Our method substantially improves the original proposal (Lobino et al 2008 Science 322 563), which uses a filtered Glauber-Sudarshan decomposition to determine the effect of the process on an arbitrary state. We introduce a new relation between the action of a general quantum process on coherent state inputs and its action on an arbitrary quantum state. This relation eliminates the need to invoke the Glauber-Sudarshan representation for states; hence, it dramatically simplifies the task of process identification and removes a potential... 

Schrödinger's famous thought experiment involves a (macroscopic) cat whose quantum state becomes entangled with that of a (microscopic) decaying nucleus. The creation of such micro-macro entanglement is being pursued in several fields, including atomic ensembles, superconducting circuits, electro-mechanical and opto-mechanical systems. Here we experimentally demonstrate the micro-macro entanglement of light. The macro system involves over a hundred million photons, whereas the micro system is at the single-photon level. We show that microscopic quantum fluctuations (in field quadrature measurements) on one side are correlated with macroscopic fluctuations (in the photon number statistics) on... 

Proton exchange membrane fuel cell (PEM-FC) aggregation pressure causes extensive strains in cell segments. The compression of each segment takes place through the cell modeling method. In addition, a very heterogeneous compressive load is produced because of the recurrent channel rib design of the dipole plates, so that while high strains are provided below the rib, the domain continues in its initial uncompressed case under the ducts approximate to it. This leads to significant spatial variations in thermal and electrical connections and contact resistances (both in rib–GDL and membrane–GDL interfaces). Variations in heat, charge, and mass transfer rates within the GDL can affect the... 

Proton exchange membrane fuel cell (PEM-FC) aggregation pressure causes extensive strains in cell segments. The compression of each segment takes place through the cell modeling method. In addition, a very heterogeneous compressive load is produced because of the recurrent channel rib design of the dipole plates, so that while high strains are provided below the rib, the domain continues in its initial uncompressed case under the ducts approximate to it. This leads to significant spatial variations in thermal and electrical connections and contact resistances (both in rib–GDL and membrane–GDL interfaces). Variations in heat, charge, and mass transfer rates within the GDL can affect the... 

Establishing high-quality communication in construction projects is essential to securing successful collaboration and maintaining understanding among project stakeholders. Indeed, poor communication results in low productivity, poor efficiency, and substandard deliverables. While high-quality communication is recognized as contingent on the interpersonal skills of workers, the impacts of communication quality on job performance remain unknown. This study addresses this deficiency by developing a method to evaluate construction workers' communication quality. A literature review is undertaken to capture salient interpersonal skills. Leadership style, listening, team building, and clarifying... 

Novel type of two-impinging-jets loop reactor (TIJLR) has been proposed and tested successfully for the solid-liquid catalytic reactions. The TIJLR was tested using the catalytic reaction of isomerization of D-glucose to D-fructose by immobilized glucose isomerase catalyst as a typical model system of solid-liquid catalytic reactions. The TIJLR is characterized by a high intensity reaction chamber, which is separated by a perforated plate from other parts of the reactor. The perforated plate was used as a filter to keep the catalyst particles within the reaction chamber. A compartment model with two adjustable parameters was considered to describe the pattern of flow within the reaction... 

Laser Powder Bed Fusion (LPBF) technology is a new trend in manufacturing complex geometric structures from metals. This technology allows producing topologically optimized parts for aerospace, medical and industrial sectors where a high performance-to-weight ratio is required. Commonly the feature size for such applications is higher than 300–400 microns. However, for several possible applications of LPBF technology, for example, microfluidic devices, stents for coronary vessels, porous filters, dentistry, etc., a significant increase in the resolution is required. This work is aimed to study the resolution factors of LPBF technology for the manufacturing of superelastic instruments for... 

A thermodynamic model considering flame propagation is presented to predict SI engine characteristics for hydrogen-methane blends. The partially charge stratification approach which involves micro direct injection of pure fuel or a fuel-air mixture, to create a rich zone near the spark plug, is proposed as a method to improve engine performance. Presented approach was validated with experimental data for the natural gas at lean condition. The model was generalized to predict the performance of engine for a variety of hydrogen contents in hydrogen-methane blends. Hydrogen molar concentrations of 0%, 15%, 30%, and 45% were used in the simulations. Results showed that partially charge... 

The paper addresses the problem of directly estimating the parameters of a reduced order digital controller using a closed loop type identification algorithm. The algorithm minimizes the closed loop plant input error between the nominal closed loop system and the closed loop system using the reduced order controller. It is assumed that a plant model (if necessary validated in closed loop with the nominal controller) is available. One of the original features of this approach is that it can use either simulated or real data. The frequency bias distribution of the parameter estimates shows that the reduced order controller maintains the critical performance of the nominal closed loop system. A... 

This study aims at analyzing the performance of three units known as low salt rejection reverse osmosis (LSRRO), split-feed counterflow reverse osmosis (SF-CFRO), and split-brine counterflow reverse osmosis (SB-CFRO) and implementing them in a modified multi-stage multi-feed counter-current membrane with cascade recycle for dewatering hypersaline streams to the salinity appropriate for crystallizers' feed. Exergy and primitive pinch analysis showed that dewatering is limited in SF-CFRO as the permeate inlet dictates the maximum salinity difference at the pinch point as well as high frictional pressure loss in the permeate channel. SB-CFRO and LSRRO units can reach high salinities by... 

Rather vertically aligned ZnO rods with flower-like structures were grown on quartz substrates through vapor phase transport method. X-ray diffraction (XRD) analysis and photoluminescence (PL) measurement were performed to determine crystalline structure and defects, respectively. H2S gas sensing properties of the grown structure were investigated at both room temperature and 250 °C for comparison. A remarkable increase in response and selectivity at room temperature compared to 250 °C was observed. High response and selectivity to low concentrations of H2S at room temperature as well as good stability make the sensor a promising candidate for practical applications  

Disposal of contaminated wastewater causes many serious problems especially when it gets mixed with the ground and seawater. It is, therefore, important to apply any remedial action to eradicate dangerous pollutants from the aqueous effluents and to avoid exposure of this wastewater to aquatic life. The research results discussed herein deal with the removal of Rhodamine B (RhB) and Congo Red (CR) dye from wastewater by using multi-walled carbon nanotubes (MWCNTs) as an adsorbent. Different factors like solid dosage, initial pH and concentration, time, and temperature were studied to understand the behavior and mechanism of adsorption. The maximum adsorption capacity in case of a single... 

Abdominal aortic aneurysm (AAA) is a serious medical condition that poses life-Threatening complications. Due to the associated risks and potential ruptures from open surgery, targeted drug delivery (TDD) has been considered an alternative treatment method. Researchers have conducted numerous studies to understand the diseases' nature, including mechanical properties and blood flow patterns, revealing that cardiovascular diseases exhibit turbulent factors such as swirling flows and fluctuations. This research focuses on analyzing how the size, shape, and capacities of drug carriers affect the transport of drugs to the AAA (Abdominal Aortic Aneurysm). AAA geometry of a patient was... 

Many existing buildings are irregular in plan or elevation because of asymmetric placement of masonry infills. The stiffness of masonry infill is a considerable value relating to that of the structure. Produced torsion from eccentricity because of infill stiffness leads to extra forces and deformations in structural members and diaphragms. An appropriate alternative to solve this problem especially in existing buildings is using dampers. Dampers can enhance structural performance by reducing seismically induced lateral displacements and by reducing inelastic behavior of beams and columns. In this paper some simple models are used to show structural modeling and a conceptual discussion is... 

We present N-body simulations of unstable spiral modes in a dynamically cool collisionless disc. We show that spiral modes grow in a thin collisionless disk in accordance with the analytical perturbation theory. We use the particle-mesh code SUPERBOX with nested grids to follow the evolution of unstable spirals that emerge from an unstable equilibrium state. We use a large number of particles (up to N = 40 & 106) and high-resolution spatial grids in our simulations (1283 cells). These allow us to trace the dynamics of the unstable spiral modes until their wave amplitudes are saturated due to nonlinear effects. In general, the results of our simulations are in agreement with the analytical... 

In this study, the effect of nanoclay on the rheological and morphological properties of polyamide 6 (PA6)/acrylonitrile-butadiene-styrene (ABS) blends was investigated. The scanning electron microscopy micrographs showed that with increment in the nanoclay content, the dispersed phase droplets size and their polydispersity index decreased, and the finer and more uniform dispersed phase was obtained. The transmission electron microscopy micrographs of nanocomposites indicated well-dispersed nanoclay tactoids in the polymer matrix produced by exfoliation of the nanoclay in the polymeric blends. Dynamic strain sweep experiments showed that the extent of the linear viscoelastic region is... 

Dye-sensitized solar cells (DSCs) with nanotubular TiO2 electrodes of varying thicknesses are compared to DSCs based on conventional nanoparticulate electrodes. Despite the higher degree of order in one-dimensional nanotubular electrodes, electron transport times and diffusion coefficients, determined under short-circuit conditions, are comparable to those of nanoparticulate electrodes. The quasi-Fermi level, however, is much lower in the nanotubes, suggesting a lower concentration of conduction band electrons. This provides evidence for a much higher diffusion coefficient for conduction band electrons in nanotubes than in nanoparticulate films. The electron lifetime and the diffusion length... 

Linear and nonlinear (in both steady and transient shear flows) rheological properties of polyamide 6/acrylonitrile-butadiene-styrene (PA6/ABS) nanocomposite blends have been investigated. Characterization of nanocomposite samples morphology by scanning electron microscopy revealed that with increasing nanoclay loading, size of dispersing phase droplets decreases significantly and their uniformity improved considerably. Transmission electron microscopy observations clearly display a coexistence of intercalate and exfoliate structure for nanoclay in the polymer-blend nanocomposite. On the other hand, we see that the tactoids are collected of a few silicate layers and possibly also of a single... 

Backgrounds In order to move towards the elimination and eradication of malaria in the world, the development of vaccines is inevitable. Many modern vaccines are based on recombinant technology; however, they may not provide a fully protective, long-lasting immune response. One of the strategies to improve recombinant vaccines is designing the nanovaccines such as self-assembling protein nanoparticles (SAPNs). Hence, the presentation of epitopes in a repeat array and correct conformation should be considered. P. falciparum generative cell-specific 1 (PfGCS1) is a main transmission-blocking vaccine candidate with two highly conserved fragments, HAP2-GCS1 and cd loop, inducing partial malaria... 

The gelatin/gum arabic microcapsules encapsulating peppermint oil were prepared by complex coacervationusing tannic acid as hardening agent. The effects of various parameters, including concentration of wall material, core material, tannic acid and Tween 80 were investigated on particle size and encapsulation efficiency. For statistical evaluation of the parameters, Taguchi method was concerned. The size of prepared spherical microcapsules was 19-66 micrometers. The results showed that, particle size increased with increasing the core and the wall concentration and decreased with increasing tannic acid and Tween 80 concentraIfd efficiency increased by increasing the core and wall...