Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Understanding the way liquid spreads through paper

30.11.2016

A team of researchers from India have created a model to explain how liquid diffuses through paper which has applications in medical testing and perfume manufacturing

Molecules move randomly, colliding with each other in continual motion. You can even smell this process at times; it's how perfume spreads across a room when the air is still. The process is termed diffusion and the theory of diffusion can be applied to liquid spreading through paper, too - a process at work in a range of everyday products, from ink pens to paper sampling patches for medical tests.


Investigators documented spreading of ink on a filter paper of Whatman Grade 1, and analyzed the process with a scanning electron microscope. Scanning micrographic results show paper fiber distribution, along with the micro-particle-image-velocimetry measure of random liquid movement through the network. Researchers conclude this evidence confirms diffusive dynamics at work in the spread of liquid through a paper matrix.

Credit: Suman Chakrabort

Now, a team of researchers in India have developed a model that deepens their conceptual grasp of how liquids spread through paper.

"Liquid spreading in a paper is essentially random liquid motion through a randomly distributed network of fibers," said Suman Chakraborty, lead researcher of the investigation at the Indian Institute of Technology Kharagpur, and the Advancement Technology Development Centre, both located in Kharagpur, India. Results are published this week in Applied Physics Letters, from AIP Publishing.

Diffusion is a well-known process. But the team's elaboration of diffusion theory in the context of paper-liquid interactions, which pose tortuous fiber networks to transport dynamics, is novel and reveals new theoretical detail. In their experiment, the researchers observed ink spreading on filter paper using a scanning electron microscope.

The team mapped liquid spreading dynamics from a single fiber capillary to a larger network of the fibers. They then computed the resulting transport characteristics, with results confirming a generalized unified perspective of diffusion at work in the process of liquid moving through a paper matrix. Scanning micrographic images show paper fiber distributions, along with the micro-particle-image-velocimetry measure of random liquid movement through the network.

"Our study reveals that, despite such diversified uses of paper interacting with liquids, there is a fundamental uniqueness of liquid spreading through paper leading toward a general and unified theory about it," Chakraborty said.

The theory holds that molecules of a liquid move through the fiber network of paper following the principles of universal diffusive dynamics. "Paper is constituted of a network of fibers distributed randomly," said Chakraborty. "As a consequence, random motion of the liquid in all possible directions occurs. We know molecules move randomly and collide with each other, and this is the premise of diffusion."

Despite wide use of liquid-infused paper technologies, there are gaps in the understanding of the basic science behind its behavior. Chakraborty and his students, Kaustav Chaudhury and Shantimoy Kar, help fill that gap.

By understanding liquid spread in the paradigm of diffusion, scientists can control it more precisely to create and refine new products that involve liquid spreading through paper. For example, current markets have validated an important potential property of paper: acting as the essential building block of a rapid diagnostic kit in an ultra-low-cost paradigm.

Examples of this application include pregnancy test strips; alkalinity or acidity tests of beauty and baby soaps using a paper strip; paper-strips for checking water quality; and medical diagnosis aided by paper-strip tests of urine, saliva and blood. The author's diffusion model of liquid spreading in paper can also improve papers and inks used for writing, drawing and painting.

Next, the investigators plan to develop smart and compact technologies for diagnostic purposes, advancing the existing paper based platforms.

"The key objectives are to obtain rapid results at the expense of low costs. To this end, the paper shows a promising prospect of being a tool to serve both the objectives. The present work, as we believe, will pave the way for the design and development of the paper-based technologies to serve a wider public," Chakraborty said.

###

The article, "Diffusive dynamics on paper matrix," is authored by Kaustav Chaudhury, Shantimoy Kar and Suman Chakraborty. The article will appear in the journal Applied Physics Letters on November 29, 2016 (DOI: 10.1063/1.4966992). After that date, it can be accessed at: http://scitation.aip.org/content/aip/journal/apl/109/20/10.1063/1.4966992

About the journal:

Applied Physics Letters features concise, rapid reports on significant new findings in applied physics. The journal covers new experimental and theoretical research on applications of physics phenomena related to all branches of science, engineering, and modern technology.

Media Contact

AIP Media
media@aip.org
301-209-3090

 @jasonbardi

http://www.aip.org 

AIP Media | EurekAlert!

More articles from Physics and Astronomy:

nachricht When electric fields make spins swirl
15.11.2018 | Institute for Basic Science

nachricht Gravitational waves from a merged hyper-massive neutron star
15.11.2018 | Royal Astronomical Society

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

When electric fields make spins swirl

15.11.2018 | Physics and Astronomy

Discovery of a cool super-Earth

15.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>