Article
Crystallography
Shuqi Yang, Huijuan Ye, Yingxin Liu
Summary: Raman spectroscopy experiments were conducted to distinguish the characteristics of inclusions in natural and heat-treated tanzanite, showing notable changes in the Raman features of inclusions like calcite and anatase in heat-treated samples.
Article
Optics
M. L. Chithambo
Summary: The study reports the phototransferred thermoluminescence of tanzanite induced by 470 nm blue light, showing three peaks at 86 degrees C. The system studied is unconventional with an indeterminate number of donors, and competition effects between donor and acceptor electron traps have been analyzed using empirical models.
JOURNAL OF LUMINESCENCE
(2021)
Article
Spectroscopy
Alessia Coccato, Danilo Bersani, Maria Cristina Caggiani, Paolo Mazzoleni, Germana Barone
Summary: This study aimed to address methodological aspects of zoisite Raman spectra, investigating orientational effects, differentiating photoluminescence bands from Raman signals using different excitation wavelengths, and evaluating the effectiveness of portable instruments in identifying tanzanite. The results showed that both portable and laboratory Raman instruments could effectively reveal zoisite despite orientational effects, opening the way to identify mounted tanzanite gemstones accurately. Additionally, the use of different excitation wavelengths allowed the distinction of photoluminescence bands and identification of rare earth elements (REEs) likely associated with the mineral's genesis.
JOURNAL OF RAMAN SPECTROSCOPY
(2022)
Article
Green & Sustainable Science & Technology
Janice Ann Denoncourt
Summary: This article analyzes how a strategy for Tanzania's tanzanite gemstone mining sector could promote gender equality and female entrepreneurship, and provides recommendations for sustainable economic development in the mine-to-market supply chain
Editorial Material
Genetics & Heredity
Dorothy Clyde
Summary: The study in Cell identified a conserved set of small non-coding RNAs that are glycosylated and found on the surface of cells, participating in extracellular interactions.
NATURE REVIEWS GENETICS
(2021)
Article
Chemistry, Applied
Fahanwi Asabuwa Ngwabebhoh, Tomas Saha, Jaroslav Stejskal, Miroslava Trchova, Dusan Kopecky, Jiri Pfleger
Summary: Conducting polymers, particularly polypyrrole, were used for surface modification of three different leathers. The polymer was deposited on collagen fibers, forming a thin layer with thickness ranging from 24 to 200 μm. The modified leathers showed changes in mechanical properties and sheet resistances, and their conductivity and electroactivity can potentially be utilized in intelligent leathers for footwear, heating elements, and energy storage.
PROGRESS IN ORGANIC COATINGS
(2023)
Article
Materials Science, Coatings & Films
Kun-An Chiu, Pin-Hsun Wu, Wei-Lin Wang, Lin-Lung Wei, Jr-Sheng Tian, Chun-Yen Peng, Yue-Han Wu, Li Chang
Summary: This study investigates the homoepitaxial growth of (111)-oriented diamond films on Au-coated and Ni-coated diamond substrates using microwave plasma chemical vapor deposition (CVD). The results show that Au and Ni islands are in epitaxy with the diamond substrate, and no diamond growth occurs on top of those islands in the early stage of diamond deposition. The overgrowth of diamond over the metal islands results in a continuous film with a lower defect density.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Public, Environmental & Occupational Health
Alexander W. Mbuya, Innocent B. Mboya, Hadija H. Semvua, Sia E. Msuya, Patrick J. Howlett, Simon H. Mamuya
Summary: The study assessed the concentrations of respirable crystalline silica (RCS) and radon among tanzanite mining communities. The results showed high exposure to RCS and radon among small-scale miners, leading to potential health risks. The study recommends strengthening health education, enforcing the use of respirators, monitoring radon exposure, and implementing mitigation measures.
ANNALS OF WORK EXPOSURES AND HEALTH
(2023)
Article
Thermodynamics
K. Chen, X. Zheng, S. N. Wang
Summary: This study developed novel activated carbon sodium polyacrylate composite coated aluminum sheets with high adsorption property and good desorption ability, and investigated their adsorption and desorption properties under different air conditions. Results showed that the composite coated aluminum sheets had significantly higher water uptake than conventional activated carbon coated samples in medium-to-high relative humidity. Adsorption capacities and rate coefficients of the composite samples with internal cooling were markedly higher than those without.
Article
Energy & Fuels
Rana Adel, Graham Morse, Francesco Silvestri, Esther Barrena, Eugenia Martinez-Ferrero, Mariano Campoy-Quiles, Priti Tiwana, Marco Stella
Summary: Efficient fabrication of organic photovoltaic (OPV) modules is crucial for their commercialization, but there is a significant performance gap between lab-scale and industrial methods. Therefore, understanding the critical steps in the upscaling process is essential to bridge this performance gap.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Review
Chemistry, Multidisciplinary
Stephen Ingram, Steven Jansen, H. Jochen Schenk
Summary: This review article introduces the presence of unique nanobubbles in the xylem of plants and discusses how the polar lipids coating them enable their persistence in a dynamic environment with negative pressure, large pressure fluctuations, and wide temperature fluctuations. The theoretical considerations about the formation of lipid-coated nanobubbles from gas-filled spaces in the xylem and the role of mesoporous fibrous pit membranes in creating the bubbles are also discussed.
Article
Chemistry, Multidisciplinary
Nikolay V. Tkachenko, Pavel Rublev, Alexander I. Boldyrev, Jean-Marie Lehn
Summary: By coating Rydberg molecules with organic skin, their ionization potential energy can be further decreased and thermodynamic stability can be increased.
FRONTIERS IN CHEMISTRY
(2022)
Article
Chemistry, Physical
Samantha Medina, Jayson G. Foster, Michael J. Dzara, Min Wang, Michael Ulsh, Scott A. Mauger, Svitlana Pylypenko
Summary: This study characterizes the structure and composition of catalyst layer (CL) in gas-diffusion electrodes (GDEs) fabricated by different coating methods. Various microscopy techniques were used to analyze the bulk, near surface, and surface composition of the CLs for a better understanding of their performance. The results demonstrate the importance of quantification parameters and surface properties in explaining and potentially predicting the performance of GDEs used in polymer electrolyte membrane (PEM) technologies.
JOURNAL OF POWER SOURCES
(2023)
Article
Public, Environmental & Occupational Health
S. Behzadinasaba, M. Hosseinia, M. D. Williamsb, H. M. Ivesterc, I. C. Allen, J. O. Falkinham, W. A. Duckera
Summary: The study demonstrates that cuprous oxide coatings have broad-spectrum antimicrobial activity against nine different micro-organisms. For example, the Cu2O/PU coating killed 99.9997% of Pseudomonas aeruginosa and 99.9993% of Staphylococcus aureus in 1 hour. These coatings maintained their efficacy after weekly cleanings and showed no cytotoxicity to human cells.
JOURNAL OF HOSPITAL INFECTION
(2022)
Article
Nanoscience & Nanotechnology
Timothy Thornber, Onkar S. Game, Elena J. Cassella, Mary E. O'Kane, James E. Bishop, Thomas J. Routledge, Tarek Alanazi, Mustafa Togay, Patrick J. M. Isherwood, Luis C. Infante-Ortega, Deborah B. Hammond, John M. Walls, David G. Lidzey
Summary: This study explores the feasibility of using ultrasonic spray coating technology to fabricate perovskite solar cells on rigid nonplanar surfaces. The researchers found that devices fabricated on glass substrates held at angles of inclination up to 45 degrees from the horizontal exhibited comparable power conversion efficiencies to those fabricated on horizontal substrates. This study represents the first successful fabrication of rigid curved perovskite solar cells.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Qingchao Zhou, Chengsi Wang, Andy Hsitien Shen
Summary: Copper nanoparticles were synthesized in natural plagioclase mineral crystals through controlled ion exchange, showing potential for practical applications in nonlinear optics. The in situ formation and mechanism of the nanoparticles were elucidated using element distribution characterization and spectroscopic measurement. The materials exhibited promising third-order nonlinear optical susceptibility values, indicating their potential as plasmonic materials for various applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Crystallography
Ratthaphon Amphon, Chawalit Chankhantha, Nirawat Thammajak, Saweat Intarasiri, Andy H. H. Shen
Summary: The color mechanism of blue sapphire is still not well understood. Two theories, intervalence charge-transfer theory and band gap theory, have been proposed. Recent studies have shown that the band gap theory is more accurate. Experimental results using UV-Vis-NIR, PIXE, and XANES techniques support this theory.
CRYSTAL RESEARCH AND TECHNOLOGY
(2023)
Article
Geochemistry & Geophysics
Quanli Chen, Peijin Bao, Yan Li, Andy H. Shen, Ran Gao, Yulin Bai, Xue Gong, Xianyu Liu
Summary: Emeralds from the Panjshir Valley in Afghanistan have gained a significant share in the market due to their high quality comparable to Colombian emeralds. To trace the origin of these emeralds, 20 samples were analyzed using various spectroscopy techniques. The results showed similarities between the Panjshir and Colombian emeralds in terms of inclusion types and coloring elements, but they could be distinguished using certain diagrams.
Review
Geochemistry & Geophysics
Zhiqing Zhang, Andy Shen
Summary: Fluorescence and phosphorescence are important optical-physical properties of gems, which are influenced by trace elements, crystal lattice defects, and luminous molecules. Luminescence spectroscopy, specifically using an excitation-emission matrix (EEM), provides detailed information about emission and excitation peaks, as well as the presence of specific elements, defects, or luminous substances in gem materials. This review paper summarizes the applications of luminescence spectroscopy in various gem materials, while emphasizing the need for further confirmation with samples from reliable sources.
Article
Geochemistry & Geophysics
Qian Zhang, Yujing Shi, Tian Shao, Xingtong Li, Fengshun Xu, Andy H. H. Shen
Summary: The luminescence behavior of light green grossular garnets under ultraviolet light was characterized using various analytical techniques. The results showed that the garnets exhibited orange-red luminescence, with broad and sharp peaks observed in the photoluminescence spectra. UV-Vis spectroscopy revealed asymmetrical absorption bands related to Cr3+ or Cr3+/V3+ and minor absorption peaks related to Mn2+. Trace elements Ti, V, Cr, and Mn were confirmed by EMPA and LA-ICP-MS analysis, while EPR spectrum confirmed the existence of Mn2+, Cr3+, and Fe3+. Interestingly, the intensity of luminescence in grossular garnets could be suppressed by higher concentrations of V.
Article
Geochemistry & Geophysics
Yunqi Yang, Chaowen Wang, Chengsi Wang, Xibing Shen, Ke Yin, Tao Chen, Andy Hsitien Shen, Thomas J. Algeo, Hanlie Hong
Summary: In recent years, it has been found that some sapphires experience color fading in sunlight and color enhancement after UV irradiation. This phenomenon is attributed to the photochromism of corundum, although the mechanism is still unclear. In this study, we conducted photochromic experiments on sapphire specimens using different light sources and observed a correlation between color instability and orange fluorescence. Additionally, we proposed an explanation for the photochromic phenomenon in yellow sapphires related to various defects and electron transfer.
Article
Geochemistry & Geophysics
Chaoyang Chen, Jing Yu, Xu Ye, Andy H. H. Shen
Summary: The pink color of the conch pearl is caused by the presence of polyene pigments, which was determined through nondestructive spectroscopic analysis and theoretical calculations. Destructive chemical analysis methods cannot be used due to the high value of the pink conch pearl.
Article
Geochemistry & Geophysics
Chuting Zhang, Chaoyang Chen, Zhibin Li, Andy H. Shen
Summary: The alexandrite effect in apatite from Kazakhstan, displayed as a color change from yellowish-green to pinkish-orange, is studied through chemical composition analysis and various spectra. The primary trace elements in the apatite are identified, and the rare-earth element, Nd, is found to be the main contributor to the alexandrite effect. This research provides a theoretical foundation for non-destructive identification of apatite exhibiting the alexandrite effect.
Article
Spectroscopy
Ma Ping, Andy Hsitien Shen, Luo Heng, Zhong Yuan
Summary: This study investigates the jadeite from Myanmar, Russia, and Guatemala using laser Raman spectroscopy. By comparing the Raman characteristics of jadeite minerals from different origins, typical jadeite spectral characteristics were found at 1 037, 988, 697, 372 and 201 cm(-1).
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
Article
Physics, Multidisciplinary
Li Qing-Xin, Huang Yan, Chen Yi-Wei, Zhu Yu-Jian, Zhu Wang, Song Jun-Wei, An Dong-Dong, Gan Qi-Kang, Wang Kai-Yuan, Wang Hao-Lin, Mai Zhi-Hong, Andy Shen, Xi Chuan-Ying, Zhang Jing-Lei, Yu Ge-Liang, Wang Lei
Summary: In this study, the electric transport behavior of bilayer graphene under electric and magnetic fields was investigated using high-quality bilayer graphene/hBN heterostructure. The observed even-denominator fractional quantum Hall state exhibits non-Abelian statistics, indicating its potential for topological quantum computation.
ACTA PHYSICA SINICA
(2022)
Article
Spectroscopy
Luo Heng, Andy Hsitien Shen
Summary: The origin and color changes of purple grape chalcedony from Indonesia were investigated through various experimental methods. The study found that the purple color is mainly caused by the absorption of a specific wavelength, while the yellow color is related to the absorption of near-ultraviolet area and blue light. In the heat treatment experiment, the purple hue gradually faded to yellow, and a new absorption peak appeared in the spectra. Furthermore, the study also revealed that the correlation between color and element content is not significant, indicating that color is not solely determined by the presence of elements but is also influenced by factors such as fine structure.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
Article
Spectroscopy
Ma Ping, Andy Hsitien Shen, Zhong Yuan, Luo Heng
Summary: Jadeite is a precious jade stone, and determining its geographical origin is crucial. This study uses UV-Vis absorption spectroscopy to identify the origin of jadeite by analyzing the absorption peaks in the spectra. The research provides a rapid and practical method for identifying the origin of jadeite.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
Article
Spectroscopy
Yang Yan-ling, Andy Hsitien Shen, Fan Yu-rong, Huang Wei-zhi, Pei Jing-cheng
Summary: A study found noticeable differences in the chemical composition and absorption spectra between new synthetic emeralds and natural emeralds. The new synthetic emeralds were vanadium-rich and iron-poor, while natural emeralds contained Fe3+, Fe2+, and Cr3+. UV-Vis-NIR spectroscopy was effective in distinguishing between natural and synthetic emeralds, but should be combined with other identification evidence.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
Article
Spectroscopy
Li Ying-ying, Zhang Zhi-qing, Wu Xiao-hong, Andy Hsitien Shen
Summary: This study investigates the fluorescence and phosphorescence properties of Indonesian fossil resins. They have at least two fluorophores contributing to visible-range fluorescence, while phosphorescence is influenced by the degree of aromatization in different parts.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
Article
Spectroscopy
Zhong Yuan, Qu Meng-wen, Andy Hsitien Shen
Summary: The study investigated the origin, chemical composition, and spectroscopic characteristics of purple-brownish red garnets. Different localities can be distinguished through linear discriminant analysis and Raman peaks. The color of garnets is influenced by chemical composition and light absorption strength.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
