What is the best method for tracking the sun position, is-it by solar position calculation along the day of the year or by other method?

In solar energy application, often we should know the sun position at each instant. With the sun position calculation, I think we can establish a database for this purpose. Then we can use-it for...

31 December 2014 7,264 12 View

In multilayer PV solar cells, how can I choose the materials (gap and contact type) in order to increase efficiency ?

When the PV solar cell is used in a multi layer form, the goal is to benefit of a large interval of solar radiations. I think that the gap and the contact of different layers must have certain...

31 December 2014 3,584 4 View

What is the energy value of a phonon generally measured in an indirect transition?

Is it possible to obtain a phonon energy of about 425 meV, or is it an indirect transition assisted with more than one phonon?

11 December 2014 6,267 1 View

Why we use the term of "optical constants" of a material in spite of their variations ? is-it by misnomer ?

Optical constants as well as the gap, represent the signing of a material. They must be specific for this material. However, optical constants depend of the size of the crystallites which form the...

11 December 2014 5,742 3 View

Can we predict barrier potential in a contact metal-semiconductor or semiconductor-semiconductor using a theoretical approach ?

From band structure obtained with an existing calculation method , can we reach the result relating to the contact barrier between two materials ?

11 December 2014 5,487 13 View

There are much old films which are colored later. How we proceed to retrieve the suitable color for original picture ?

There are much old films which are colored later. The obtained result seems to be satisfactory. The colors can be different from the originals but it is sufficient for mistaking the human eyes....

11 December 2014 8,546 1 View

The IR radiations are harmful for the performances of photovoltaic solar cells; how is-it possible to eliminate these kind of radiations ?

Among the parameters which decrease the efficiency of the photovoltaic solar cells, we can note the solar IR radiations. This kind of radiation increases the temperature and then disturbs often...

11 December 2014 447 17 View

Is it possible to obtain a natural colored image using electron microscopy or ecography ?

Until today, a good colored image is obtained using exclusively light. Electron microscope uses electrons and echograph uses ultrason. That gives only gray images.

10 November 2014 7,733 11 View

What kind of chemical products are generally used in order to target a given thin film by the CBD technique?

08 September 2014 9,211 2 View

What is the best chemical solution which can be used to obtain tungsten oxide in the framework of chemical bath deposition (CBD)?

Especially to target the WO3 oxide.

02 March 2014 2,843 2 View

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

MGL tools

20 June 2021 0 0 View

How climate change will influences human and animal behavioral change?

The role of climate change influencing the human behavior as well as economics interest

01 June 2021 0 0 View

flexibility of polymers chain

effect of double bond on the flexibility of polymers

07 April 2021 0 0 View

i have some problem with chtMultiRegionSimpleFoam

--> FOAM FATAL ERROR: Maximum number of iterations exceeded From function Foam::scalar Foam::species::thermo::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar) const) const [with Thermo = Foam::hConstThermo >; Type = Foam::sensibleEnthalpy; Foam::scalar = double; Foam::species::thermo = Foam::species::thermo >, Foam::sensibleEnthalpy>] in file /home/ubuntu/OpenFOAM/OpenFOAM-4.1/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 66. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::calculate() at ??:? #3 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::correct() at ??:? #4 ? at ??:? #5 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #6 ? at ??:?

24 March 2021 0 0 View

Formulation of polymer color flakes

I am writing to request some information for making polymer color flakes. I would appreciate the help.

17 March 2021 0 0 View

Physics: Why do we describe light by referring to its wavelength, but microwaves and radar pulses by referring to their frequency?

In physics, the description of the properties of light generally refers to its wavelength (nm), while in the range of microwaves and radio waves we refer to the frequency of a signal (e.g. kHz or...

03 March 2021 1,682 3 View

Why can't make aluminum nitride film successfully by use sputter?

We use reactive sputtering process to make aluminum nitride film, and want to make c-axis aluminum nitride film on a silicon substrate, but the crystal orientation cannot be seen with...

03 March 2021 7,975 3 View

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10?

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10? Since, the growth curve from day 2 to 10 won't be like the "Logistic curve" it might not follow logistic...

03 March 2021 1,401 3 View