In the beginnig of solidification,nucleation occurs with a positive Gibbs free energy difference.why?

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Is there a process for changing crystalline silicon nanostructures or nanoparticles to amorpous silicon which is going to be used in Li ion batteries?

Amorphous silicon has lower volumetric change than crystalline silicon during first cycles of charge and discharge. How can we prepare amorpous silicon from nanostructured crystalline silicon? Is...

10 November 2019 2,401 4 View

How to clean copper surface before coating process?

What are suitable reagents for removing oxide layer and grease or organic impurities from copper surface before the coating process?

07 August 2019 2,913 4 View

How to leach Fe impurities out of Silicon Suspension?

High energy ball milling used to prepare silicon micro and nano particles. I used magnetic separation to remove iron. But there is a small amount of iron left in the suspension. How can I remove...

06 July 2019 4,269 2 View

How to calculate density of a coating layer?

It's a coating with few micrometers in thickness. There are equations for thickness prediction. But for using them, I need to know the coating density. I'm using spray coating method. The...

06 July 2019 6,846 4 View

What are suitable reagents for color eching of AISI 304 stainless steel?

Any reagent for revealing microstructure, electroetching, chemical etchin, or other methods. I need the colorful microstructure image. I only need the artistic aspect of images!

06 July 2019 6,161 3 View

What are flow lines?

Does anyone knows a reference book that describes this phenomena? Are flow lines and shear bands the same or they're different from each other? why flow lines appear in micro structure? (Attached...

01 February 2018 3,036 0 View

Why second phase particles cluster during cold work?

In the attached picture, rolling direction is from bottom to the top(vertical).

01 February 2018 1,905 0 View

Can grain structure be revealed using SEM?

can we see the grains and grain boundaries without using any etching procedure by SEM?

11 December 2017 7,982 2 View

What is the main reason for edge cracking of aluminum alloys during cold rolling?

sheet edge geometry change, workability limitation or something else?? Does anyone have studied about that?

09 October 2017 4,589 3 View

Can Quench and Partitioning heat treatmnet(Q/P) improve the impact energy of AISI 4140 steel?

08 September 2017 3,443 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

After a reference from Int J Body Compos Res, can any body help?

Hi, I am after the reference below, my library says it cannot obtain a copy either locally or internationally, any help appreciated! Chris Wang ZM, Heshka S, Wielopolski L, Pi-Sunyer FX, Pierson...

03 March 2021 6,193 1 View

Irradiation data for JAPAN?

Hi, Could you help me to get the latest (2019, 2020) solar resource data for a particular site in JAPAN? PV GIS and NSRDB data are not in reach to JAPAN, I'm looking for some other database for...

03 March 2021 961 3 View

Why are the velocities so high in my Boussinesq approximation Fluent simulation?

Hello, I have a mechanism where air rises due to convective flows. In this simulation, nothing is driving the air except this. I understand that the Boussinesq approximation only works for small...

02 March 2021 4,910 3 View

Why almost every element would be metallized in sufficiently high pressure and low temperature?

(This statement is from wikipedia, BTW). What is so special about metallic bond that is limiting high-P low-T state of a matter (as long as individual atoms exist, not white dwarf of neutron star...

02 March 2021 3,309 2 View

Can we distinguish the type of free fluid inside the pelvic and abdominal cavities whether blood or serous fluid using the ultrasound?

during ultrasound examination of acute abdomen, sometimes we see free fluid , can we know the type of fluid ,whether blood or not , using ultrasound only? if yes , what are the sonographic...

01 March 2021 7,476 4 View

How Can I bring as much common elements in steel as possible to calculate stable phase(s) in OpenCalphad?

As I was tweaking step-by-step OpenCalphad6 Macros step1.ocm involving phase and thermal property calculation of a High-speed steel, I could not incorporate more than 6 elements in the steel...

01 March 2021 8,840 1 View

How can you bring two structures together to create an adhesive bond in LAMMPS?

I have created an Ice 1h crystalline structure and an Aluminium substrate structure and equilibrated both at 250K. Now I need to bring them together in a way that an adhesive bond is created....

01 March 2021 3,325 2 View

What is the state of the drug inside solid lipid nanoparticles (SLNs)?

I am a little confuse with the mechanism of solid lipid nanoparticles (SLNs). The main point of encapsulating drugs into SLNs is because some drugs have low solubility in water. Therefore, SLNs...

01 March 2021 3,703 3 View

What is the density for pva electrospining?

I'm Juan Carlos, a high school student who is working with electropinning, I made an electropinning machine with a 21g needle and a 30kv high voltage source and the distance between my needle is...

28 February 2021 298 3 View