Tag Archives: Peng Li

A unique design for harvesting biomechanical motion

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Researchers have discovered a new technique for doing this according to an April 25, 2022 news item on ScienceDaily,

Harvesting energy from the day-to-day movements of the human body and turning it into useful electrical energy, is the focus of a new piece of research involving a Northumbria University Professor.

Academics from Northwestern Polytechnical University in China, supported by Professor Richard Fu from Northumbria, have developed a unique design for sensors capable of using human movements — such as bending, twisting and stretching — to power wearable technology devices including smart watches and fitness trackers.

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An April 25, 2022 Northumbria University press release (also on EurekAlert), which originated the news item, delves further into the topic (Note: Links have been removed),

Self-powered pressure sensors are one of the key components used in these smart electronic devices which are growing in popularity today. The sensors can operate without the need for external power supplies.

Detecting health conditions and measuring performance in sport are among the potential uses for these types of sensors. As a result, they are the focus of extensive research and development, but remain challenging to produce with the performance sensing, flexibility, and sufficient level of power needed for wearable technology.

A new research paper published in the prestigious international scientific journal, Advanced Science, describes how the team led by Professor Weizheng Yuan, Professor Honglong Chang and Associate Professor Kai Tao from Northwestern Polytechnical University (NPU), has worked with Professor Fu to develop a solution.

Their novel method involves using sophisticated materials with pre-patterned pyramid shapes to create friction against the silicone polymer known as polydimethylsiloxane or PDMS. This friction generates a self-powering effect, or triboelectricity, which can significantly enhance the energy available to power a wearable device. 

Professor Tao from NPU explained: “This results in a self-powered tactile sensor with wide environmental tolerance and excellent sensing performance, and it can detect subtle pressure changes by measuring the variations of triboelectric output signal without an external power supply. The sensor design has been tested an is capable of controlling electrical appliances and robotic hands by simulating human finger gestures, confirming its potential for use in wearable technology.”

Professor Fu added: “This self-powered sensor based on hydrogels has a simple fabrication process, but with a superb flexibility, good transparency, fast response and high stability.”

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Professor Honglong Chang, Dean of School of Mechanical Engineering at NPU, said Northumbria University is one of their most important international partners.

“One of our important tasks this year is to further promote the cooperative relationship with Northumbria University,” he explained. “We are organising NU-NPU bilateral academic forums this year, and we look forward to establishing strong collaborations in various research areas with Northumbria University.”

Professor Jon Reast, Pro Vice-Chancellor (International) at Northumbria University, said he was delighted with the success of the partnership with NPU. “It’s fantastic that this research collaboration is proving successful and producing such ground-breaking work.

“We work closely with more than 500 partner universities, colleges and schools across the world. Within these, NPU is one of a set of extremely high-quality research-led university partners. The relationship with NPU includes researchers within smart materials engineering as well as smart design and is producing some truly excellent, impactful, research in both areas.”

Here’s a link to and a citation for the paper,

Ultra-Sensitive, Deformable, and Transparent Triboelectric Tactile Sensor Based on Micro-Pyramid Patterned Ionic Hydrogel for Interactive Human–Machine Interfaces by Kai Tao, Zhensheng Chen, Jiahao Yu, Haozhe Zeng, Jin Wu, Zixuan Wu, Qingyan Jia, Peng Li, Yongqing Fu, Honglong Chang, Weizheng Yuan. Advanced Science Volume 9, Issue 10 April 5, 2022 2104168 DOI: https://doi.org/10.1002/advs.202104168 First published: 31 January 2022

This paper is open access.

Clay nanosheets and world food security

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This is some interesting agricultural research from Australia. From a Jan. 11, 2017 news item on phys.org,

A University of Queensland team has made a discovery that could help conquer the greatest threat to global food security – pests and diseases in plants.

Research leader Professor Neena Mitter said BioClay – an environmentally sustainable alternative to chemicals and pesticides – could be a game-changer for crop protection.

“In agriculture, the need for new control agents grows each year, driven by demand for greater production, the effects of climate change, community and regulatory demands, and toxicity and pesticide resistance,” she said.

“Our disruptive research involves a spray of nano-sized degradable clay used to release double-stranded RNA, that protects plants from specific disease-causing pathogens.”

The research, by scientists from the Queensland Alliance for Agriculture and Food Innovation (QAAFI) and UQ’s Australian Institute for Bioengineering and Nanotechnology (AIBN) is published in Nature Plants.

A Jan. 11, 2017 University of Queensland press release, which originated the news item, provides a bit more detail,

Professor Mitter said the technology reduced the use of pesticides without altering the genome of the plants.

“Once BioClay is applied, the plant ‘thinks’ it is being attacked by a disease or pest insect and responds by protecting itself from the targeted pest or disease.

“A single spray of BioClay protects the plant and then degrades, reducing the risk to the environment or human health.”

She said BioClay met consumer demands for sustainable crop protection and residue-free produce.

“The cleaner approach will value-add to the food and agri-business industry, contributing to global food security and to a cleaner, greener image of Queensland.”

AIBN’s Professor Zhiping Xu said BioClay combined nanotechnology and biotechnology.

“It will produce huge benefits for agriculture in the next several decades, and the applications will expand into a much wider field of primary agricultural production,” Professor Xu said.

Here’s a link to and a citation for the paper,

Clay nanosheets for topical delivery of RNAi for sustained protection against plant viruses by Neena Mitter, Elizabeth A. Worrall, Karl E. Robinson, Peng Li, Ritesh G. Jain, Christelle Taochy, Stephen J. Fletcher, Bernard J. Carroll, G. Q. (Max) Lu & Zhi Ping Xu. Nature Plants 3, Article number: 16207 (2017) doi:10.1038/nplants.2016.207 Published online: 09 January 2017

This paper is behind a paywall.

I don’t usually do this but here’s the abstract for the paper,

Topical application of pathogen-specific double-stranded RNA (dsRNA) for virus resistance in plants represents an attractive alternative to transgenic RNA interference (RNAi). However, the instability of naked dsRNA sprayed on plants has been a major challenge towards its practical application. We demonstrate that dsRNA can be loaded on designer, non-toxic, degradable, layered double hydroxide (LDH) clay nanosheets. Once loaded on LDH, the dsRNA does not wash off, shows sustained release and can be detected on sprayed leaves even 30 days after application. We provide evidence for the degradation of LDH, dsRNA uptake in plant cells and silencing of homologous RNA on topical application. Significantly, a single spray of dsRNA loaded on LDH (BioClay) afforded virus protection for at least 20 days when challenged on sprayed and newly emerged unsprayed leaves. This innovation translates nanotechnology developed for delivery of RNAi for human therapeutics to use in crop protection as an environmentally sustainable and easy to adopt topical spray.

It helps a bit but I’m puzzled by the description of BioClay as an alternative to RNAi in the first sentence because the last sentence has: “This innovation translates nanotechnology developed for delivery of RNAi … .” I believe what they’re saying is that LDH clay nanosheets were developed for delivery of RNAi but have now been adapted for delivery of dsRNA. Maybe?

At any rate this paper is behind a paywall.

Acoustofluidics and lab-on-a-chip for asthma and tuberculosis diagnostics

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This is my first exposure to acoustofluidics (although it’s been around for a few years) and it concerns lab-on-a-chip diagnostics for asthma and tuberculosis. From an Aug. 3, 2015 news item on Azonano,

A device to mix liquids utilizing ultrasonics is the first and most difficult component in a miniaturized system for low-cost analysis of sputum from patients with pulmonary diseases such as tuberculosis and asthma.

The device, developed by engineers at Penn State in collaboration with researchers at the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health, and the Washington University School of Medicine, will benefit patients in the U.S., where 12 percent of the population, or around 19 million people, have asthma, and in undeveloped regions where TB is still a widespread and often deadly contagion.

“To develop more accurate diagnosis and treatment approaches for patients with pulmonary diseases, we have to analyze sample cells directly from the lungs rather than by drawing blood,” said Tony Jun Huang, professor of engineering science and mechanics at Penn State and the inventor, with his group, of this and other acoustofluidic devices based on ultrasonic waves. “For instance, different drugs are used to treat different types of asthma patients. If you know what a person’s immunophenotype is, you can provide personalized medicine for their particular disease.

A July 29, 2015 Pennsylvania State University news release, which originated the news item, describes the disadvantages of the current sputum analyses techniques and explains how this new technique in an improvement,

There are several issues with the current standard method for sputum analysis. The first is that human specimens can be contagious, and sputum analysis requires handling of specimens in several discrete machines. With a lab on a chip device, all biospecimens are safely contained in a single disposable component.

Another issue is the sample size required for analysis in the current system, which is often larger than a person can easily produce. The acoustofluidic sputum liquefier created by Huang’s group requires 100 times less sample while still providing accuracy equivalent to the standard system.

A further issue is that current systems are difficult to use and require trained operators. With the lab on a chip system, a nurse can operate the device with a touch of a few buttons and get a read out, or the patient could even operate the device at home. In addition, the disposable portion of the device should cost less than a dollar to manufacture.

Po-Hsun Huang, a graduate student in the Huang group and the first author on the recent paper describing the device in the Royal Society of Chemistry journal Lab on a Chip, said “This will offer quick analysis of samples without having to send them out to a centralized lab. While I have been working on the liquefaction component of the device, my lab mates are working on the flow cytometry analysis component, which should be ready soon. This is the first on-chip sputum liquefier anyone has developed.”

Stewart J. Levine, a Senior Investigator and Chief of the Laboratory of Asthma and Lung Inflammation in the Division of Intramural Research at NHLBI, said “This on-chip sputum liquefier is a significant advance regarding our goal of developing a point-of-care diagnostic device that will determine the type of inflammation present in the lungs of asthmatics. This will allow health care providers to individualize asthma treatments for each patient and advance the goal of bringing precision medicine into clinical practice.”

Here’s a link to and a citation for the paper,

An acoustofluidic sputum liquefier by Po-Hsun Huang, Liqiang Ren, Nitesh Nama, Sixing Li, Peng Li, Xianglan Yao, Rosemarie A. Cuento, Cheng-Hsin Wei, Yuchao Chen, Yuliang Xie, Ahmad Ahsan Nawaz, Yael G. Alevy, Michael J. Holtzman, J. Philip McCoy, Stewart J. Levine, and  Tony Jun Huang. Lab Chip, 2015,15, 3125-3131 DOI: 10.1039/C5LC00539F

First published online 17 Jun 2015

This is an open access paper but you do need to register for a free (British) Royal Society of Chemistry publishing personal account.

Speeding up the process for converting carbon dioxide into hydrocarbon fuel

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This is a personal thrill; it’s the first time in seven years that I’ve received a press release directly from an institution in Asia.

A March 10, 2015 MANA, the International Center for Materials Nanoarchitectonics at NIMS (National Institute for Materials Science) press release announces and describes hydrocarbon fuel research from Japan and China first published online in Nov. 2014 and later in print in January 2015,

A combination of semiconductor catalysts, optimum catalyst shape, gold-copper co-catalyst alloy nanoparticles and hydrous hydrazine reducing agent enables an increase of hydrocarbon generation from CO2 by a factor of ten.

“Solar-energy-driven conversion of CO2 into hydrocarbon fuels can simultaneously generate chemical fuels to meet energy demand and mitigate rising CO2 levels,” explain Jinhua Ye and her colleagues at the International Center for Materials Nanoarchitectonics in their latest report. Now the research team have identified the conditions and catalysts that will maximise the yield of hydrocarbons from CO2, generating ten times previously reported production rates.

Carbon dioxide can be converted into a hydrocarbon by means of ‘reduction reactions’ -a type of reaction that involves reducing the oxygen content of a molecule, increasing the hydrogen content or increasing the electrons. In photocatalytic reduction of CO2 light activates the catalyst for the reaction.

Ye and his team introduced four approaches that each contributed to an increased reaction rate. First, they combined two known semiconductor photocatalysts strontium titanate (STO) and titania [titanium dioxide] (TiO2) – which led to the separation of the charges generated by light and hence a more effective photocatalyst. Second, the high surface area of the nanotubes was made greater by holes in the tube surfaces, which enhances catalysis by increasing the contact between the gases and catalysts. Third, the tubes were decorated with gold-copper (Au3Cu) nanoparticle co-catalysts to further enhance the catalysis, and fourth, they used hydrous hydrazine (N2H4•H2O) as the source of hydrogen.

Although the high hydrogen content of hydrous hydrazine is widely recognised in the context of hydrogen storage there are no previous reports of its use for reduction reactions. The researchers demonstrated that the reducing properties of hydrous hydrazine were so great that oxidation of the co-catalytic nanoparticles – a problem when water or hydrogen are used – was avoided.

The researchers conclude their report, “This opens a feasible route to enhance the photocatalytic efficiency, which also aids the development of photocatalysts and co-catalysts.”

Affiliations

The researchers on this project are associated with the following institutions:

International Center for Materials Nanoarchitectonics (MANA), and the Environmental Remediation Materials Unit,  National Institute for Materials Science (NIMS) 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan

Graduate School of Chemical Science and Engineering, Hokkaido University, Sapporo 060-0814, Japan

TU-NIMS Joint Research Center, School of Material Science and Engineering, Tianjin University 92 Weijin Road, Tianjin,  P.R. China

Here’s a link to and a citation for the paper,

Photocatalytic Reduction of Carbon Dioxide by Hydrous Hydrazine over Au–Cu Alloy Nanoparticles Supported on SrTiO3/TiO2 Coaxial Nanotube Arrays by Dr. Qing Kang, Dr. Tao Wang, Dr. Peng Li, Dr. Lequan Liu, Dr. Kun Chang, Mu Li, and Prof. Jinhua Ye. Angewandte Chemie International Edition Volume 54, Issue 3, pages 841–845, January 12, 2015 DOI: 10.1002/anie.201409183 Article first published online: 24 NOV 2014

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This research is behind a paywall.