It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Monday, June 22, 2026
Watching water nanodrops spread themselves thin
Institute of Industrial Science, The University of Tokyo
Researchers at the Institute of Industrial Science, The University of Tokyo, carry out computer experiments to track how water nanodroplets wet surfaces
Credit: Institute of Industrial Science, The University of Tokyo
Tokyo, Japan – Why does water roll off a duck’s back but spread on clean glass? For macroscopic (mm-scale) drops, this behavior can be explained using continuum theory. However, when nanoscale (10–9 mm) droplets spread on surfaces, a force called the line tension becomes relevant and mysteriously changes sign. Questions about the nature of this force and its relevance to water’s interaction with surfaces have remained unanswered.
Now, researchers from the Institute of Industrial Science, The University of Tokyo, have carried out computational studies that explain the origin of line tension in water nanodroplets at a molecular level. This discovery will be reported in Nature Physics.
On hydrophobic surfaces like Teflon, water forms spherical beads and slides off, a process known as nonwetting. On a waxy leaf, water forms stable, round drops, corresponding to partial wetting. On clean glass, water spreads into a thin film, referred to as complete wetting. Substrate wettability is the ability of liquids to maintain contact with a solid surface. Changing the substrate wettability can drive wetting from partial to complete.
At the edge of a water droplet on a surface, three phases come into contact. The shape of a macroscopic droplet is determined by the balance of forces at three interfaces (solid–air, liquid–solid, and liquid–air) along the contact line.
An additional force acts along the contact line – line tension. For a macroscopic drop, the line tension is much smaller than the interfacial tension. However, for nanoscale drops, the contact line is comparable in size to the drop. At complete wetting, line tension can become important and reverse sign, strongly affecting nanoscale wetting behavior. This phenomenon cannot be explained within a purely continuum description.
The team performed computer experiments (molecular dynamics simulations) to examine how water molecules organize at a surface during wetting. The team then quantified the line tension for different substrate wettabilities.
“In liquid water, hydrogen bonds tend to organize water molecules into a local, short-range tetrahedral structure—a transient four-neighbor pattern,” explains lead author, Mohd Moid. “It is difficult to perform physical experiments to probe how this tetrahedral order evolves when water completely wets a surface.”
However, the computer experiments showed that the tetrahedral order collapses at the contact line at complete wetting. This structural change is linked to a change in the sign of the line tension.
“We also performed computer experiments on an ice bilayer on a hydrophilic surface,” reports Hajime Tanaka, senior author. “Ice bilayers consist of two layers of water molecules. We found that the bilayer did not wet the surface, showing that local order can outweigh surface chemistry.”
This work shows that the interfacial liquid structure is a key determinant of wettability, providing a new design principle for controlling interfacial mechanics and wetting in inorganic and biological systems.
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The article, “Structural origin of line-tension reversal in nanoscale wetting of water,” will be published in Nature Physics at DOI: 10.1038/s41567-026-03299-z.
About Institute of Industrial Science, The University of Tokyo
The Institute of Industrial Science, The University of Tokyo (UTokyo-IIS) is one of the largest university-attached research institutes in Japan. UTokyo-IIS is comprised of over 120 research laboratories—each headed by a faculty member—and has over 1,200 members (approximately 400 staff and 800 students) actively engaged in education and research. Its activities cover almost all areas of engineering. Since its foundation in 1949, UTokyo-IIS has worked to bridge the huge gaps that exist between academic disciplines and real-world applications.
NEW YORK, NY, JUNE 19, 2026—The world’s first HIV-positive-to-HIV-positive lung transplant was performed at NYU Langone Health.
The surgery brings new hope for HIV-positive patients in need of lung transplants, as it opens a pool of potential donors who were previously ineligible.
“This is a watershed moment for the HIV-positive community and represents real progress in creating equity in organ transplantation,” said Sapna Mehta, MD, clinical director of NYU Langone Transplant Institute and co-architect of the research protocol, sanctioned by the U.S. Food and Drug Administration, that enabled the complex procedure. “While these transplants are still only allowable under certain research protocols, this marks an expansion of options for people in need of a lifesaving organ.”
Approximately 1.2 million people in the United States are living with HIV. People with HIV can live long, healthy lives due to advances in antiretroviral therapies, or ART. Most people using ART are unable to transmit the virus and have near-normal life expectancies.
A Breath of Fresh Air
Bertrand Nelson, 56, has had HIV for nearly 26 years. In 2000, he was diagnosed with HIV and sarcoidosis, which can affect the lungs and spread to the liver. The disease had not yet spread from his lungs, and soon after diagnosis his doctors told him it was in remission.
Then, in 2021, he acquired Legionnaires’ disease and was hospitalized for weeks with severe pneumonia. The disease reactivated his sarcoidosis, which attacked his liver. His condition worsened in 2024—he required an increasing amount of oxygen to breathe—and his doctor referred him to NYU Langone Transplant Institute to be evaluated for both lung and liver transplants. A research protocol for lung transplantation under the 2013 HIV Organ Policy Equity Act, or HOPE Act, had begun, and he was evaluated for HOPE dual-organ transplant in 2025.
“Transplantation of HOPE hearts and abdominal organs has been done before, but this has not been done in lung transplantation. It takes a special kind of patient to be willing to do something that hasn’t been done before,” said Mark A. Sonnick, MD, transplant pulmonologist at NYU Langone Transplant Institute and co-author of the research protocol with Dr. Mehta.
NYU Langone Transplant Institute is one of the only transplant centers in the United States equipped and approved under a research protocol to perform HOPE lung transplants. Nelson received the first in the world on March 21, 2026, by Stephanie H. Chang, MD, surgical director of lung transplantation at NYU Langone. He received a new liver that same day, performed by Karim J. Halazun, MD, surgical director of liver transplantation at NYU Langone.
Nelson is now off oxygen for the first time in four years and getting back in shape after years of limited mobility.
He credits his mother, who will be 82 in August, for always supporting him and helping him throughout his journey.
“I want to be well for her,” he said. “I want her to see me thriving.”
He hopes his story of perseverance might inspire others and help raise awareness of people in the HIV community in need.
“There are so many others who need access to this level of care, and the more organs that become available, the better the odds of finding the right match and living a long life,” he said.
About NYU Langone Health
NYU Langone Health is a fully integrated health system that consistently achieves the best patient outcomes through a rigorous focus on quality that has resulted in some of the lowest mortality rates in the nation. Vizient Inc. has ranked NYU Langone No. 1 out of 118 comprehensive academic medical centers across the nation four years in a row, and U.S. News & World Report recently ranked four of its clinical specialties No. 1 in the nation. NYU Langone offers a comprehensive range of medical services with one high standard of care across seven inpatient locations, its Perlmutter Cancer Center, and more than 330 outpatient locations in the New York area and Florida. The system also includes two tuition-free medical schools, in Manhattan and on Long Island, and a vast research enterprise.
Wet coffee grounds turned into high-grade solid fuel in just 90 seconds
A world-first flame plasma pyrolysis technology eliminates the need for pre-drying, turning moisture-laden organic waste into anthracite-grade biochar with industrial potential
Credit: Korea Institute of Geoscience and Mineral Resources(KIGAM)
Addressing a Growing Waste Challenge
Every year, global coffee consumption generates more than 10 million tons of spent coffee grounds, most of which end up landfilled or incinerated, releasing greenhouse gases and polluting the environment.
Spent coffee grounds hold real energy potential, but their high moisture content has long been a barrier. Converting them into fuel or carbon products typically requires energy-intensive pre-drying, making large-scale resource recovery economically impractical.
World-First Flame Plasma Pyrolysis Technology
To overcome this challenge, the KIGAM team developed Flame Plasma Pyrolysis (FPP), a process that directly treats biomass containing approximately 55% moisture under atmospheric-pressure plasma conditions.
The system generates plasma flames at temperatures of approximately 800–900°C through the combustion of liquefied petroleum gas (LPG) and compressed air. Unlike conventional pyrolysis technologies, the process eliminates the need for any pre-drying treatment.
During processing, the intense thermal energy rapidly vaporizes moisture trapped inside the biomass particles. The resulting pressure buildup triggers microscopic explosions known as the "popcorn effect," which simultaneously enhance carbonization and create highly porous structures. Rather than acting as a barrier, moisture itself becomes a steam-activation agent that accelerates reactions and improves product quality.
Anthracite-Level Fuel Performance
Under optimized conditions, the researchers achieved complete conversion within 90 seconds, with a mass reduction of 83.3%.
The resulting biochar exhibited a heating value of 29.0 MJ/kg, approximately 33 percent higher than the original coffee grounds (21.8 MJ/kg) and comparable to that of anthracite coal.
Additional performance improvements included:
• Nearly threefold increase in fixed carbon content (from 15.6% to 46.2%)
• Complete removal of sulfur compounds, preventing sulfur oxide (SOx) emissions during combustion
• Specific surface area increased from 1.5 to 115.4 m²/g, indicating potential use as an activated carbon precursor or adsorption material
• Minimal formation of secondary pollutants such as smoke and tar
These characteristics make the biochar suitable not only as a renewable solid fuel but also as a high-value carbon material for environmental and industrial applications.
Dramatically Faster than Existing Technologies
The new process offers substantial advantages in both processing speed and energy efficiency.
Compared with hydrothermal carbonization (HTC), which typically requires one to six hours, the FPP process is 40 to 240 times faster. It also reduces treatment time by more than 20-fold compared with torrefaction, which generally requires at least 30 minutes.
Because the system relies on combustion-generated plasma rather than electricity-intensive plasma devices, it lowers overall energy consumption while maintaining high processing performance.
The researchers emphasize that the ability to directly process wet feedstocks without pre-drying represents one of the most significant economic and environmental advantages of the technology.
Potential for Distributed Waste-to-Energy Systems
Beyond coffee waste, the technology is potentially applicable to a wide range of high-moisture organic wastes, including food waste, sewage sludge, and agricultural residues.
Its compact process design and ultra-fast treatment capability make it particularly attractive for decentralized on-site waste-to-energy facilities, where transportation and drying costs often limit resource recovery efforts.
Research Context
The research was published in the Chemical Engineering Journal (Elsevier, Impact Factor 13.2), a leading international journal in chemical engineering. The study demonstrates a new approach for transforming wet organic waste into valuable energy resources while advancing carbon-neutral waste management strategies.
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"This technology presents a new paradigm in which waste is no longer viewed as a disposal problem but as a valuable energy resource," said Dr. Taejun Park, lead author of the study. "We plan to expand the technology to various types of high-moisture organic waste and further optimize the process for industrial-scale commercialization."
About KIGAM
The Korea Institute of Geoscience and Mineral Resources (KIGAM) is a government-funded research institute specializing in geoscience, mineral resources, energy technologies, and Earth system science. KIGAM conducts research to support sustainable resource utilization, carbon neutrality, and national resilience against environmental challenges.
The process proceeding in a clean manner, with almost no smoke or oil observed during treatment
(a) SEM images at different exposure times. (b) Schematic illustrating the transformation from non-porous raw SCG to peak porosity and eventual collapse with extended treatment.
Credit
Korea Institute of Geoscience and Mineral Resources(KIGAM)
Microalgae have long been viewed as a promising source of renewable fuel. They grow quickly, capture carbon dioxide efficiently, and do not compete with food crops for farmland. Yet turning algae into usable liquid fuels remains difficult because algae-derived bio-oil often contains high levels of oxygen and nitrogen compounds, which can lower fuel quality, reduce stability, and create pollution concerns during combustion.
A new study published in Biocharreports a promising strategy to address this challenge. Researchers developed a HZSM-5 coated biochar catalyst, known as HZSM-5@biochar, and paired it with wet torrefaction, a water-based pretreatment process, to convert Chlorella microalgae into valuable aromatic hydrocarbons. These compounds, especially benzene, toluene, and xylene, commonly known as BTX, are important chemical building blocks for fuels, plastics, and other industrial products.
“Our goal was not only to improve the quality of algae-derived pyrolysis products, but also to understand why the catalyst works,” said corresponding author Liangliang Fan. “By combining wet torrefaction with a biochar-supported zeolite catalyst, we were able to promote deoxygenation and denitrogenation while suppressing catalyst deactivation.”
In the study, the team first treated Chlorella through wet torrefaction at different temperatures. This step helped remove part of the oxygen and nitrogen from the biomass before pyrolysis. The pretreated microalgae were then rapidly heated in the presence of the HZSM-5@biochar catalyst. Under optimized conditions, including wet torrefaction at 200 °C, pyrolysis at 500 °C, and a catalyst-to-feedstock ratio of 20:1, the process achieved up to 96.06% aromatic selectivity. Among these products, BTX selectivity reached 83.24%, with a BTX yield of 94.64 mg per gram of feedstock.
The catalyst also sharply reduced unwanted compounds. Under non-catalytic conditions, oxygen-containing and nitrogen-containing products accounted for 82.14% of the pyrolysis products. With HZSM-5@biochar, that share fell to just 3.26%, showing strong removal of heteroatoms that normally limit the use of algae-based bio-oil.
To explain the mechanism, the researchers studied model compounds representing the main components of microalgae, including proteins, lipids, and carbohydrates. They also examined typical pyrolysis products such as long-chain alkenes, amides, fatty acids, aldehydes, and nitrogen-containing heterocycles. These experiments suggested that biochar and HZSM-5 play complementary roles. Biochar provides mesopores and surface sites that help adsorb and pre-crack larger molecules, while HZSM-5 provides strong acidic sites and micropores that drive aromatization.
This two-step catalytic effect appears to reduce one of the major problems in catalytic pyrolysis: coking. Coke deposits can block catalyst pores and cause rapid deactivation. After one use, HZSM-5@biochar produced only 0.33% coke, compared with 1.87% coke on conventional HZSM-5. The composite catalyst also maintained excellent performance over six reuse cycles after regeneration.
“The biochar support acts like a protective front line,” Fan said. “It helps break down unstable large molecules before they can clog the zeolite pores, allowing the catalyst to keep producing aromatics more efficiently.”
The findings provide new insight into how biochar-based composite catalysts can upgrade nitrogen-rich biomass such as microalgae. By improving fuel quality, increasing BTX production, and enhancing catalyst stability, the work could help advance cleaner and more efficient pathways for producing renewable fuels and industrial chemicals from algae.
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Journal Reference: Hu, J., Wang, Y., Jiang, H. et al. In-depth into the mechanism of aromatic production from catalytic pyrolysis of wet-torrefied microalgae with HZSM-5 coated biochar. Biochar8, 91 (2026).
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
URBANA, Ill. – Soils that are exposed to prolonged drought often develop desiccation cracks, which impact soil properties and exacerbate moisture loss through evapotranspiration. A new study from the University of Illinois Urbana-Champaign examines the evolution of soil cracking and how cracks interact with storage and movement of water in the soil. The findings can help improve hydrological models essential for water management.
Soils are generally described based on their texture and structure, explained co-author Maria Chu, professor in ABE. “Texture refers to the percentages of sand, silt, and clay that make up the soil. Structure describes how these different components are arranged into clumps or aggregates. When the soil cracks it affects the organization of components, changing the soil structure.”
The research team built a lysimeter – an instrument which measures the water balance of soil – to replicate field conditions in the lab. The lysimeter contained a column with one cubic foot of silt loess, a soil common in the U.S. Midwest. They added an environmental chamber with temperature control and a tile drain to allow for drainage flow.
In the lysimeter, the researchers simulated heat wave conditions at 40 degrees Celsius and exposed the soil to multiple cycles of wetness and drying to mimic soil crack evolution.
“We cannot directly measure evaporation, but we can estimate the total loss of water from the soil by tracking the changes in weight through time, which can indicate the amount of water that has been lost from the system,” said co-author Jorge Guzman, research assistant professor in ABE.
The researchers also attached a camera on top of the environmental chamber and monitored the propagation of cracks through time, measuring the area occupied by cracks relative to the total area of the soil surface. They correlated this information with the hydrologic variables observed from the subsurface and evaporation rate.
“Most hydrological models assume soil structure to be static, whereas we're trying to determine how changes in soil structure affect the hydrologic variables over time. This will be helpful in assessing drought impacts, as well as the soil water availability,” Dela Cruz said.
Once soil cracks have developed, they tend to remain stable over time if there is no intervention, permanently affecting the soil’s ability to retain moisture.
“Soil without cracks is more protected against water loss. We can see from our data that the cracks accelerate the process of water transfer from the soil to the air. Then, the soil area that contacts the air becomes drier, and it changes the dynamic of how water redistributes in the soil. Eventually there is a decrease in evaporation, but that’s because the water is already gone,” Guzman explained.
“While the experiment focused on bare soil, it will also be important to evaluate the impact of vegetation and transpiration from plants,” he added. “What happens once you have soil cracks and vegetation, and the soil and plants are competing for water?”
The paper, “Desiccation cracks and their impacts on bare soil evaporation,” is published in Soil & Tillage Research [DOI: 10.1016/j.still.2026.107207].
Research in the College of ACES is made possible in part by Hatch funding from USDA’s National Institute of Food and Agriculture. The study was also supported by a seed grant provided by the University of Illinois Urbana-Champaign Department of Agricultural and Biological Engineering and the University of Illinois Urbana-Champaign Campus Research Board.
