We present a systematic investigation of the formation mechanism of carbogenic nanoparticles (CNPs), otherwise referred to as C-dots, by following the pyrolysis of citric acid (CA)-ethanolamine (EA) precursor at different temperatures. Pyrolysis at 180 °C leads to a CNP molecular precursor with a strongly intense photoluminescence (PL) spectrum and high quantum yield formed by dehydration of CA-EA. At higher temperatures (230 °C) a carbogenic core starts forming and the PL is due to the presence of both molecular fluorophores and the carbogenic core. CNPs that exhibit mostly or exclusively PL arising from carbogenic cores are obtained at even higher temperatures (300 and 400 °C, respectively). Since the molecular fluorophores predominate at low pyrolysis temperatures while the carbogenic core starts forming at higher temperatures, the PL behavior of CNPs strongly depends on the conditions used for their synthesis.
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http://dx.doi.org/10.1021/ja204661r | DOI Listing |
J Biomol Struct Dyn
December 2024
School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded, Maharashtra, India.
The dielectric behavior of Asparagine (CHNO) in water over the frequency range of 10 MHz to 30 GHz in the temperature region of 278.15-303.15 K in a step of 5 K has been carried out using time domain reflectometry (TDR) at various concentrations of asparagine.
View Article and Find Full Text PDFInt Microbiol
December 2024
Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 2455, 11451, Riyadh, Saudi Arabia.
The present research work is concerned with the production and optimization of the dopa-oxidase enzyme by using pre-grown mycelia of Aspergillus oryzae. Different strains of A. oryzae were collected and isolated from various soil samples.
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December 2024
Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan.
The surface of the eye is constantly exposed to the external environment and is affected by atmospheric conditions and air pollution, and dry eye is a typical ocular surface disease. The aim of this study is to determine whether there are seasonal differences in the number of dry eye operations in Japan and to investigate whether meteorological conditions and air pollutants are related to. The operations were examined using the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) database from fiscal years 2019 to 2021.
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December 2024
School of Electrical and Information, Hunan University, Changsha, 410083, China.
Accurately predicting solar power to ensure the economical operation of microgrids and smart grids is a key challenge for integrating the large scale photovoltaic (PV) generation into conventional power systems. This paper proposes an accurate short-term solar power forecasting method using a hybrid machine learning algorithm, with the system trained using the pre-trained extreme learning machine (P-ELM) algorithm. The proposed method utilizes temperature, irradiance, and solar power output at instant i as input parameters, while the output parameters are temperature, irradiance, and solar power output at instant i+1, enabling next-day solar power output forecasting.
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December 2024
School of Mechanical and Electrical Engineering, Qiqihar University, Qiqihar, 161006, China.
A prediction model of the pig house environment based on Bayesian optimization (BO), squeeze and excitation block (SE), convolutional neural network (CNN) and gated recurrent unit (GRU) is proposed to improve the prediction accuracy and animal welfare and take control measures in advance. To ensure the optimal model configuration, the model uses a BO algorithm to fine-tune hyper-parameters, such as the number of GRUs, initial learning rate and L2 normal form regularization factor. The environmental data are fed into the SE-CNN block, which extracts the local features of the data through convolutional operations.
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