Science topic

# DES - Science topic

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Questions related to DES

In compressible flows, would improvements based on the SST K-Epsilon turbulence model , such as the use of AI，be a more promising direction in engineering. ten or thirty years from now, will the most commonly used model be the Reynolds stress model or its deformation, or will DES be the most commonly used simulation method.

I am making a DES in order to produce levulinic acid

Generally, while performing antioxidant activities, we evaporate the solvent in which extraction is performed to obtain the dry weight of sample. The dried powder is then used to make dilutions, and we carry out TPC and TFC on them. However, while using a non-volatile solvent like DES or glycerol, we cannot evaporate the solvent used for extraction. Hence we are unable to obtain the dry mass of the plant extract. How should the procedure be performed and what sort of calculation should we then use to get our final answer in mg GAE/g DW or mg RE/g DW.

The equation formally used is:

C = (c x V)/ m

I want to predict whether a certain molecular pair will form DES or not, is there one or more parameters that can be calculated from MD simulations from which I can know if this molecular pair will form DES or not?

While implementing DES and AES using python I wane to measure memory consumption,CPU utilization.

Hello everyone,

My goal is to know how accurate is my simulation using the Wall Modeled Large Eddy Simulation (WMLES) S-omega and to calculate the total turbulent kinetic energy.

Therefore I would like to know if I'm resolving 80% of the turbulent kinetic energy with my grid and to do that I need to compute the SGS turbulent kinetic energy and compute the ratio between the resolved and total turbulent kinetic energy (k_resolved / (k_resolved + k_sgs) )

Assuming the resolved turbulent kinetic energy can be calculated by:

- k_resolved = 0.5 * (U_RMSE ^2 + V_RMSE ^2 + W_RMSE ^2 )

Is there a way to compute k_sgs using the various parameters given by Fluent ?

The turbulent parameters that Fluent has available are:

- Subgrid Turbulent Viscosity
- Subgrid Effective Viscosity
- Subgrid Turbulent Viscosity Ratio
- Subgrid Filter Length
- Effective Thermal Conductivity
- Effective Prandtl Number
- Wall Yplus

The article referenced in the Fluent user theory guide is (PDF) A hybrid RANS-LES approach with delayed-DES and wall-modelled LES capabilities (researchgate.net)

According to the guide, the subgrid filter length is given by the equation (4) and the subgrid turbulent viscosity is given by equation (19).

Thank you for reading,

Hi everyone. I am using DES model to simulation turbulent flow with RE 6500. I am only getting one vortex and not getting any vortex shedding. I tried to use URans model, but it shows no vortices and only wake region behind cylinder. Please inform me whats effect of model on vortex shedding.? Will LES provide vortex shedding or there is some other reason of not getting vortex shedding. Thanks

Most studies have focused on HBDs and their effects in processes involving DES. Is there a reason for such an inclination on the study of HBDs and not HBAs, especially in terms of biomass fractionation?

Some authors are using a series of new alternative of ionic liquids, named DES and Ch-DES and claimed to overcome the disadvantages of conventional extraction methods. How these solvents overcome it? What are the main advantage and problems and issues related to these components for extraction of high value chemicals/ phenolic compound etc extraction from various bioresources ?

the DES i'm working on is thymol:camphor

Hi! I`ve got question about DESs. How can I proof the formation of DES? If speak about IR, which regions should I look at and which bands can indicate on the presence of hydrogen bonds? And one more question: the addition of water results full distruction of DES or water will only dilute DES? Is there any information about how much water I can add to the DES before it stop being DES and become "water and dissolved substances"?

If I prepared a DES from choline chloride (ChCl) by quantifying ChCl by some means, what effect will the water have on the final product? How will HBD-HBA interaction be effected? Will a DES be formed at all under these conditions?

Dear

Madem/Sir I Need Payload Encryption and Decryption With 3DES in Python And C Language Please This Code Is Very Necessary For Me Please Anyone Find out This Code For Me and Send Me

My system consists of ionic liquids, aliphatic and aromatic hydrocarbons. Any suggestions and any script for calculation of viscosity?

A patient with hereditary desminopathy (mutation Thr341Pro DES in a heterozygous state) with disease progression has a significant decrease in taste. How can this fact be explained?

Hi, everyone.

I am starting to work with fractionation of Biomassa by Deep Euthetic Solvents .

I came across a DES that is comprised of Lactic acid: Glucose:water (molar ratio 5:1:3), as in ref.

My problem beguns as I found out lactic acid is sold only as a 85% (w/w) solution. So when I do the math, I will have a surplus of water.

My idea is to do a reduced pressure destilation of the lactic acid to remove water and obtain pure lactic adic, and then add water and glucose on the proper molar ratios.

Anyone out there that has experience with that, is it the proper approach? Any other ideas?

Thanks.

We all know that cipher(algorithm) design is publicly known and only key is hidden. So if everyone knows substitution, permutation details what is the point to add these layers in any symmetric key encryptions algorithm ?

Dear All,

Which type of simulations is good to investigate the rotating stall in axial compressor? RANS, URANS, LES, DES, and DNS. Secondly, a single passage or multi passage is recommended for the investigation of rotating stall.

Hubble constant estimates from collaborations: Planck’s mission, SDSS-III Baryon Oscillation Spectroscopic Survey, DES Collaboration, H0LiCOW, Riess et al, Hubble Space Telescope are objective and not in doubt. It means that the Hubble constant describes two similar, but different physical processes, therefore objectively have at least two meanings. An estimate of the Hubble constant based on relict radiation describes the process of rotation of the space of the observed Universe, and an estimate of the Hubble constant which based on measuring changes in the distance to distant objects of the observed Universe (quasars, Cepheids, red giants ...) describes the process of rotation of substance in the space of the observed Universe. The Hubble constant with equal success presents two mutually exclusive hypotheses: the hypothesis about of the dark energy and the hypothesis of rotation of the space of the observable Universe. The hypothesis of the dark energy admits only one value of the Hubble constant and the hypothesis of rotation of the space of the observed Universe admits a multi-valued Hubble constant. Forecast: all estimates of the Hubble constant based on relic radiation will be grouped around its analytical estimate 1) 67.5577 (km / s) / Mpc, and estimates of the Hubble constant based on measurements of distances from distant objects of the observable Universe will be grouped around its second analytical value 2) 74.15 (km / s) / Mpc.

It can be assumed that the rotation speed of a substance with a mass density that is substantially lower than that of quasars, Cepheids, and red giants will be between 1) and 2).

There are four general types of DES but i think none of them particularly address potassium carbonate based DES. Should it be regarded as a new type of DES?

I need to synthesize high volumes of DES with choline chloride.

Hi!

I`ve read lots of articles "how to make DES", and that is what I`m interested in:

It`s absolutele clear that "to make DES you need just combine substance 1(HBA) and substance 2 (HBD) in a known molar ratio, then heat and stirring until homogeneous liquid is formed - congratulation - you`ve got DES!"

Ok, let`s try. I took ChCl and Oxalic acid in molar ratio 1:2, put them on water bath (80oC), made them constantly stirred. They formed liquid, I took them away from water bath and let them cooled. And they become solid immediately after cooling.

So where is the problem? I made it without water. Maybe they need some water ?

Or it`s normal that they become solid, and I need to carry out all my subsequent experiments at 40-50oC?

I am working on a external aerodynamics vehicle CFD simulation in which I want to make sure, that the flow that actually hits my vehicle has a certain level of turbulence intensity. Therefore I am using a DES Spalart-Allmaras turbulence model. I set up a region further down in my flow volume in which I am adding a turbulence source in the form of modified turbulent diffusivity (no other option of defining turbulence possible) - the variable transported in the Spalart-Allmaras approach.

However I see major fast decay of this variable, starting right after its introduction to the field. Which parameters can I change to reduce the rate of decay of the modified turbulent diffusivity in my field - with the goal to keep it higher then a certain level for some time and thereby keeping a certain level of turbulence intensity.

Menthol:lactic acid DES is strongly acidic, this negatively impact the extraction of acid labile lipophilic molecules such as lycopene from tomatoes. l wonder if it is possible to bring it to an almost neutral pH value. Does anyone have suggestions?

Basically, biomechanical stent modeling can be divided into three areas. The first area belongs to the modeling related to the mechanical properties of the stent, the checking of the stress states of deformations, the arrangement of the voltage on the wall of the blood vessel, etc. and mainly these tests are based on the Finite Element Method (FEM). It is very important to carry out all the tests at this stage in order to find out all design defects in time, because any irregularity discovered later requires a return to this stage and a re-testing, and this can be a very "expensive" step both materially and temporally. In the second area, the influence of the stent design itself (for example, the shape and layout of the sticks) on the flow of fluid (blood) within the blood vessel is studied and is based on the computational fluid dynamics (CFD), an area belonging to the FEM. In the third area, it is also investigated and tested for the release of the drug in DES stents and its spreading through the bloodstream, penetration into the blood wall.

Modeling partially observable systems can be useful in many applications. There are multiple techniques and tools to model DES (Discrete Event Systems) and partially observable systems using Stochastic Timed Petri Nets. It would be good if we model the system using STPN for fault detection. Thus, my question is "Do you have any idea how to model partially observable systems using Stochastic Timed Petri Nets for fault detection?"

I want to obtain names of all the FTC of DES to write a survey paper about this subject. I know only three methods: Supervisory Control appraoch, control reconﬁguration approach, hiding approach.

There is no literature reviews on this topic so the choice of articles is really a critical task.

- Are there places in the world where DID is integrated into culture (e.g. hmong shamanism) or appears in folklore?

- What are some places that are better and that are worse at recognizing DID?

- Does the whole world use the DES?

- When DID is diagnosed, what are the treatments in places other than America/Europe?

It is known that the complexation of a quaternary ammonium salt with a metal salt or hydrogen bond donor (HBD) resulting in DES formation. The charge delocalization occurring through hydrogen bonding between for example a halide ion and the hydrogen-donor moiety is responsible for the decrease in the melting point of the mixture relative to the melting points of the individual components. However the DES is not form between TEAI and Glycerol at 80 C and in varying molar ratios i.e., 1:2, 1.4, 1:6 and 1:8. I would like to know the reason why DES is not formed in this case.

DES are often seen as green solvents, however, their chemistry and mechanism is still scarcely available. How do they posses lower melting and freezing tendencies in-comparisons to their original constituents? And what are their potential applications in industry?

DES (diethylstilbestrol) is a man-made (synthetic) form of estrogen, a female hormone.

Does anyone have any historical data or any physican who may have insight on DES.

Finds well, but what new you are adding to DES as it is already broken by cryptanalyst in 1977 by using "DES Cracker" machine. so how are you securing

An example

**hybrid modelling**is mixing SD with DES sub-models, where elements in the sub-models**communicate and exchange date****continuously**as the hybrid model is run.Let us say one has built the SD sub-model using Vensim, and the DES sub-model is built using AnyLogic, what are the ways of making both sub-models to communicate during run time

High Level Architecture approach in combination with Microsoft Excel using Visual Basic for Applications is possible, but this seems to be for periodic and non-frequent communication of the sub-models. So, this approach may be convoluted if used to model a situation where the sub-models need to communicate continuously or in minuscule time steps.

Does anyone have a simplistic approach for modelling the data exchange between sub-models built using different packages?

There are many software for system modeling such as MATLAB/Simulink, AMESim, Dymola, Easy-5 etc. They are comparable in terms of functionality. Some are decent for combinations of different type of modelings; for example AnyLogic allows you to combine SD with ABM.

Is there any in which combining SD with DES is possible?

Hi,

I am going to simulate a 2D aeroacoustics simulation in Fluent using a DES model on a stator. Actually, the simulation should be performed on a complete 3D rotor-stator setup but due to some limitations, I don’t have access to the rotor geometry and computing power. A simplified model of my setup is shown in the attached picture.

I have been searching for parameters that I can extract from the DES simulations. These are the following parameters that I can think of:

1)A common parameter is the FFT of pressure data recorded in the wake region of the blade. Using FFT, I want to see if I can see tonal noise peaks or broadband peaks. Based on these observations I can characterize the sound sources such as vortex shedding or just random turbulence.

2) Another parameter that I have come across is the sound pressure which can be calculated by subtracting the instantaneous pressure from the average pressure. How this can be done in Fluent, I am not sure.

3) The other is " divergence of velocity" or dilatation contours. I found it in this article

I am not able to understand what's the significance of this parameter.

4) Another quantity that can be visualized is the normalized Q-criterion, but this will be good to see the turbulence sources and not aeroacoustics as such.

5) Also, I was wondering if one can actually extract the noise from a pressure signal at a point so that you can hear it. I came across this in the STAR-CCM+‘s user guide some time ago and they say that it can be done. The guide mentioned that that one needs to perform inverse FFT of the signal.

Perhaps, people with experience in aeroacoustics can suggest me any additional parameters that can be used. Although the near-field region sound is of interest and not far-field, I am open to using the FW-H model if it provides additional insights.

Despite of notable results of decreasing restenosis in patients who have used Drug-eluting stents, There are doubts about impact of DESs on thrombosis and death after one year. Is this been proven as a serious issue or it's ignorable?

S-Boxes in AES and DES effect diffusion in these block cipher systems. I am trying to understand which aspects of these S-boxes attribute to the symmetry of the cipher system. (i.e. If encryption is in one direction, the decryption is in the reverse direction with the same key.)

Optimal management of patients on NOACs after ACS and PCI with DES.