Results 71 to 80 of about 4,639 (219)

Proposition of Hyper‐Chemical Exchange Saturation Transfer Subtraction Spectroscopy to Detect Very Weak and Broad Signals Hidden Under Baseline and Widen Range of Materials Accessed by Hyperpolarized 129Xe NMR

ChemPhysChem, Volume 26, Issue 23, November 28, 2025.
A polyimide sample, for which hyperpolarized 129Xe NMR spectroscopy failed to detect 129Xe embedded in the polymer (Inset A), is found to give a very broad peak, line width 11 kHz at 206.5 ppm, by applying the stopped‐flow hyper‐chemical exchange saturation transfer subtraction spectroscopy on the continuous‐flow recirculating hyper‐polarization system
Hideaki Fujiwara, Hirohiko Imai, Atsuomi Kimura   +2 more
wiley   +1 more source

Advancing PET through direct imaging of three-photon decay using pure positron emitters

Communications Physics
Positronium is abundantly formed inside the human body during positron emission tomography (PET). Its properties, such as lifetime and three-photon decay rate, are highly sensitive to the microenvironment, particularly oxygen partial pressure and the ...
Macoto Fujimoto, Riku Sato, Moh Hamdan, Mizuki Uenomachi, Peter Caradonna, Laura Stephenson, Archie Montgomery, Julien Bordes, James R. Brown, Daniel P. Watts, Kenji Shimazoe   +10 more
doaj   +1 more source

Physisorption of Positronium on Quartz Surfaces [PDF]

Physical Review Letters, 2007
The possibility of having positronium (Ps) physisorbed at a material surface is of great fundamental interest, since it can lead to new insight regarding quantum sticking and is a necessary first step to try to obtain a Ps$_2$ molecule on a material host.
Saniz, R., Barbiellini, B., Platzman, P. M., Freeman, A. J.   +3 more
openaire   +3 more sources

Unleashing the Potential of Defect Engineered Persistent Pr3+‐Activated Phosphors for Multi‐Dimensional Anti‐Counterfeiting and X‐Ray Imaging Applications

Small, Volume 21, Issue 46, November 20, 2025.
Enhanced multicolor persistent luminescence with optimized trap depths (≈0.73 eV) in Ca3Ga2Ge3O12:Pr3+ phosphors enable advanced anti‐counterfeiting, optical storage, and high‐resolution X‐ray imaging (4 lp mm−1), surpassing commercial screens.
Annu Balhara, Santosh K. Gupta, Partha Sarathi Ghosh, Malini Abraham, Mohit Tyagi, Ashok Kumar Yadav, Subrata Das, Kathi Sudarshan, P. S. Sarkar   +8 more
wiley   +1 more source

Enhanced Electromagnetic Wave Absorption in Mapbi3 Hybrid Perovskite Through a Defect‐Tunable Green Synthesis

Small Structures, Volume 6, Issue 9, September 2025.
Mechanosynthesis allowed synthesizing and providing large amount of high‐quality MAPbI3 powders with defects tuned by grinding time. Mechanosynthesized MAPbI3 for 4 h dispersed in a polymeric matrix led to a marked enhancement in dielectric loss at 11.4 GHz, which makes this green synthesis approach promising for producing hybrid perovskites with ...
Yihui Cai, Dominique Begin, Christophe Lefevre, Charles Sidhoum, Erik Elkaim, Pascal Boulet, Pierre Desgardin, Marie‐France Barthe, Ricardo Helm, Werner Egger, Maik Butterling, Andreas Wagner, Vasiliki Papaefthimiou, Spiros Zafeiratos, Damien Cianferani, Loic Mager, Ovidiu Ersen, Catherine Corbel, Clément Sanchez, Sylvie Begin‐Colin   +19 more
wiley   +1 more source

Positronium Chemistry: Origin, Development, and Historical Roots

Substantia
Positronium science has for more than half a century been an important research area located somewhere between physics and chemistry. Based upon the study of positrons and the electron-positron atom called positronium, the field was originally part of ...
Helge Kragh
doaj   +1 more source

Identification and Reversible Optical Switching of NV+ Centers in Diamond

Advanced Functional Materials, Volume 35, Issue 35, August 28, 2025.
NV+ centers in diamond are predicted to coexist with NV0 and NV– centers, but direct experimental confirmation remains challenging. Using positron annihilation spectroscopy with in situ light illumination, a charge transition NV+/0 is observed at 1.234(8) eV.
Marcel Dickmann, Lucian Mathes, Ricardo Helm, Vassily Vadimovitch Burwitz, Werner Egger, Johannes Mitteneder, Christoph Hugenschmidt, Peter Sperr, Maik Butterling, Maciej Oskar Liedke, Andreas Wagner, Joachim Dorner, Thomas Schwarz‐Selinger, Günther Dollinger   +13 more
wiley   +1 more source

Positronium ions and molecules [PDF]

, 1990
Recent theoretical studies on positronium ions and molecules are discussed. A positronium ion is a three particle system consisting of two electrons in singlet spin state, and a positron.
Ho, Y. K.
core  

Nonrelativistic variational calculations of the positronium molecule and the positronium hydride [PDF]

Physical Review A, 2006
Highly accurate ground-state nonrelativistic variational calculations of ${\mathrm{Ps}}_{2}$, $^{1}\mathrm{H}\mathrm{Ps}$, and $^{\ensuremath{\infty}}\mathrm{H}\mathrm{Ps}$ are reported. The calculations have been performed using 5000 explicitly correlated Gaussian basis functions and yielded the lowest variational energy upper bounds for these systems
Sergiy Bubin, Ludwik Adamowicz
openaire   +1 more source

Oxygen Vacancy Engineering of Metal Oxide Materials for Photoelectrochemical Water Splitting

Electron, Volume 3, Issue 3, August 2025.
Oxygen vacancies play an important role in the metal oxide photoanodes for photoelectrochemical water splitting. In this review, we have summarized the recent progress on oxygen vacancies in metal oxide photoanodes and their impact on light absorption, charge separation, catalytic activity, etc.
Xiao‐Fan Yang, Guang‐Ping Yi, Peng‐Fei Lv, Si‐Jie Wen, Yi‐Ping Zhao, Zhao Jing, Qiang Wang, Bing Li, Peng‐Yi Tang   +8 more
wiley   +1 more source