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The (e_(g)■e_(u))■E_(g) product Jahn-Teller effect in the neutral group-Ⅳ vacancy quantum bits in diamond

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npj Computational Materials 2019年第1期5卷 1002-1007页

作者： GergőThiering adam Gali Wigner Research Centre for Physics Hungarian Academy of SciencesPO Box 49Budapest 1525Hungary Department of Atomic Physics Budapest University of Technology and EconomicsBudafokiút 8.Budapest 1111Hungary

The product Jahn-Teller effect may occur for such coupled electron-phonon systems in solids where single electrons occupy double degenerate *** propose that the excited state of the neutral XV split-vacancy complex in diamond,where X and V labels a group-Ⅳ impurity atom of X=Si,Ge,Sn,Pb and the vacancy,respectively,is such a system with e_(g) and e_(u) double degenerate orbitals and E_(g) quasi-localized *** develop and apply ab initio theory to quantify the strength of electron–phonon coupling for neutral XV complexes in diamond,and find a significant impact on the corresponding optical properties of these *** results show good agreement with recent experimental data on the prospective SiV(0)quantum bit,and reveals the complex nature of the excited states of neutral XV color centers in diamond.

关键词： neutral vacancy quantum

POTENTIAL OPERATORS AND LAPLACE TYPE MULTIPLIERS ASSOCIATED WITH THE TWISTED LAPLACIAN

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Acta Mathematica Scientia 2017年第1期37卷 280-292页

作者： adam NOWAK Krzysztof STEMPAK Instytut Matematyczny Polska Akademia NaukSniadeckich 800-656 WarszawaPoland Wydziat Matematyki Politechnika WroctawskaWyb.Wyspianskiego 2750-370 WroclawPoland

We study potential operators and,more generally,Laplace-Stieltjes and Laplace type multipliers associated with the twisted *** characterize those 1 ≤ p,q ≤ ∞,for which the potential operators are Lp—Lq *** result is a sharp analogue of the classical Hardy-Littlewood-Sobolev fractional integration theorem in the context of special Hermite *** also investigate Lp mapping properties of the Laplace-Stieltjes and Laplace type multipliers.

关键词： twisted Laplacian special Hermite expansion negative power potential op-erator fractional integral potential kernel spectral multiplier singular oscil-latory integral

Endoscopic ultrasound-guided drainage of peripancreatic fluid collections: What impacts treatment duration?

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Hepatobiliary & Pancreatic Diseases International 2023年第3期22卷 310-316页

作者： adam Przybyłkowski Piotr Nehring Department of Gastroenterology and Internal Medicine Medical University of WarsawWarsawPoland

Background:Peripancreatic fluid collections(PFCs)are complications resulting from acute or chronic pancreatitis and require treatment in certain clinical *** present study aimed to identify the factors influencing the duration of endoscopic ultrasound(EUS)-guided drainage of symptomatic pancreatic pseudocysts(PPCs),walled-off necrosis(WON),and acute necrotic collections(ANCs).Methods:This was a retrospective cohort study of 68 patients with PFCs who underwent EUS-guided *** timing and duration of EUS-guided drainage of various PFCs(ANC,WON,and PPCs)were compared,and the factors influencing the duration of endoscopic treatment were ***:The mean time to first EUS-guided PFC drainage since the acute pancreatitis episode was 372.0,505.0,and 18.7 days for WON,PPC,and ANC,respectively,and the mean duration of treatment was 90,60,and 63 days,respectively.A disconnected pancreatic duct,a history of percutaneous drainage,and an infected PFC were identified as factors influencing the treatment duration.A positive correlation was observed between the treatment duration and patients’*** with a disconnected pancreatic duct had to undergo more *** patients with PPC,clinically successful drainage was more frequently achieved after a single procedure without the need for repeated procedures than in those with WON(90%vs.59%,P=0.01).Conclusions:Patients with a history of percutaneous drainage,disconnected pancreatic duct,or PFC infection may require longer endoscopic treatment.

关键词： Cyst Drainage Endoscopy Pancreas Pancreatitis

Treatment of tunnel wash waters-experiments with organic sorbent materials. PartⅡ: Removal of toxic metals

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Journal of Environmental Sciences 2008年第8期20卷 1042-1045页

作者： PARUCH adam M ROSETH Roger Bioforsk-the Norwegian Institute for Agricultural and Environmental Research Soil and Environment Division

In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxicant pollutants defined in surface water quality criteria. Concentrations of these metals in the collected effluent...

关键词： electrostatic filters reduction level sorbents tunnel toxic metals treatment efficiency wash water

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Finding stable multi-component materials by combining cluster expansion and crystal structure predictions

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npj Computational Materials 2023年第1期9卷 2137-2146页

作者： adam Carlsson Johanna Rosen Martin Dahlqvist Materials Design Department of PhysicsChemistryand Biology(IFM)Linköping UniversitySE-58183 LinköpingSweden

A desired prerequisite when performing a quantum mechanical calculation is to have an initial idea of the atomic positions within an approximate crystal *** atomic positions combined should result in a system located in,or close to,an energy ***,designing low-energy structures may be a challenging task when prior knowledge is scarce,specifically for large multi-component systems where the degrees of freedom are close to *** this paper,we propose a method for identification of low-energy crystal structures within multi-component systems by combining cluster expansion and crystal structure predictions with density-functional theory *** structure prediction searches are applied to the Mo_(2)AlB_(2) and Sc2AlB_(2) ternary systems to identify candidate structures,which are subsequently used to explore the quaternary(pseudo-binary)(Mo_(x)Sc_(1–x))2AlB_(2) system through the cluster expansion formalism utilizing the ground-state search ***,we show that utilizing low-energy structures found within the cluster expansion ground-state search as seed structures within crystal structure predictions of(Mo_(x)Sc_(1–x))2AlB_(2) can significantly reduce the computational *** this combined approach,we not only correctly identified the recently discovered Mo_(4/3)Sc_(2/3)AlB_(2) i-MAB phase,comprised of in-plane chemical ordering of Mo and Sc and with Al in a Kagomélattice,but also predict additional low-energy structures at various *** result demonstrates that combining crystal structure prediction with cluster expansion provides a path for identifying low-energy crystal structures in multi-component systems by employing the strengths from both frameworks.

关键词： structure cluster crystal

Landmark learning by the Ozark zigzag salamander Plethodon angusticlavius

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Current Zoology 2011年第4期57卷 485-490页

作者： adam L. CRANE Alicia MATHIS Department of Biology Missouri State University Springfield MO 65897 USA

Although salamanders have been shown to respond to classical conditioning, spatial learning has been largely unstudied. We tested whether salamanders could learn to locate foraging areas by using landmarks. We trained 10 salamanders Plethodon angusticlavius to use landmarks （small rocks） to locate patches within the arena containing food （blackworms Lumbriculus variegatus）. At the comers of each square testing arena were four plastic dishes, one containing blackworms and the other three empty. A rock was placed in front of the dish containing blackworms, and the location of the food-dish was randomly chosen for each training trial. A control group was also trained to feed on blackworms in the presence of a rock, but the rock was positioned randomly among the four dish locations so that the rock was not a reliable landmark for the worms. Although the length of the training period for individual salamanders varied （22-38 trainings per individual）, the mean number of trainings for salamanders in the control and experimental groups was equal （30 training trials）. During testing, no blackworms were present to eliminate any visual or chemical cues emanating directly from the prey. Individuals trained with the rock landmarks spent sig- nificantly more time in the area of the landmark than did control salamanders [Current Zoology 57 （4）： 485-490, 2011].

关键词： Landmark learning Spatial learning Salamander learning Plethodon angusticlavius Beacon

Phylogenetic status of Pneumocystis from corticosteroid-treated gerbils

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Science China(Life Sciences) 2010年第10期53卷 1239-1246页

作者： RODNEY D adam Department of Medicine and Immunobiology University of Arizona College of Medicine

Pneumocystis spp. infect the lungs of multiple mammalian species and cause disease in immunosuppressed individuals. The Pneumocystis isolates that have been studied to date fall into two major clades, those from primates and those from rodents. Within each of these clades, different species have been described on the basis of host specificity and differences in sequence and morphology. Here, we demonstrate that dexamethasone immunosuppression consistently results in histologically apparent lung infection in gerbils (28/35 animals). Sequence analysis of the 18S, 5.8S and internal transcribed spacer regions of the rDNA and a portion of the mitochondrial large subunit rDNA demonstrated that this gerbil Pneumocystis is grouped with other rodent Pneumocystis spp., but is distinct from them. Our results suggest that gerbil Pneumocystis differs sufficiently from Pneumocystis species found in other rodents to be considered a separate species.

关键词： 5.8S rRNA gene gerbil internal transcribed spacers (ITS) mitochondrial large subunit (mtLS) rRNA gene 18S rRNA gene Pneumocystis

Use of coals and wastes in a co-gasification process aimed at producing hydrogen rich gas

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International Journal of Coal Science & Technology 2022年第6期9卷 161-167页

作者： Rafal Gssior adam Smoliński Polish Mining Group Inc. KatowicePoland Central Mining Institute KatowicePoland

The use of low-quality coals and flotoconcentrates is currently severely limited,and the problem of managing municipal waste from anthropogenic activities is currently a *** problems of reducing carbon dioxide emissions,utilizing the energy potential of waste and increasing its recycling have an impact on the costs of electricity *** the abundant streams of unused fuels,they can be considered as attractive energy materials,so environmentally-friendly and cost-effective options for their utilization should be developed.A study was conducted using steam co-gasification technology on selected coals,flotation concentrates and Refuse Derived Fuel(RDF)alternative *** low-quality coals were combined with RDF alternative fuel in a process aimed at hydrogen *** experiments produced gas with hydrogen concentrations ranging from 67%(vol.)to 68%(vol.)with low methane *** was observed that the addition of alternative fuels helped to increase the hydrogen concentration in *** was paid to the catalytic ability of the metal oxides contained in the fuel blend,with particular reference to K_(2)O and Al_(2)O_(3)and TiO_(2).

关键词： Coal Hydrogen Flotation concentrate Refuse derived fuel Catalytic capacity Catalysts

Spatio-temporal coupled mode theory for nonlocal metasurfaces

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Light(Science & Applications) 2024年第2期13卷 267-282页

作者： adam Overvig Sander A.Mann Andrea Alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY10031USA Physics Program Graduate Center of the City University of New YorkNew YorkNY10016USA

Diffractive nonlocal metasurfaces have recently opened a broad range of exciting developments in nanophotonics research and applications,leveraging spatially extended—yet locally patterned—resonant modes to control light with new degrees of *** conventional grating responses are elegantly captured by temporal coupled mode theory,current approaches are not well equipped to capture the arbitrary spatial response observed in the nascent field of nonlocal ***,we introduce spatio-temporal coupled mode theory(STCMT),capable of elegantly capturing the key features of the resonant response of wavefront-shaping nonlocal *** framework can quantitatively guide nonlocal metasurface design while maintaining compatibility with local metasurface frameworks,making it a powerful tool to rationally design and optimize a broad class of ultrathin optical *** validate this STCMT framework against full-wave simulations of various nonlocal metasurfaces,demonstrating that this tool offers a powerful semi-analytical framework to understand and model the physics and functionality of these devices,without the need for computationally intense full-wave *** also discuss how this model may shed physical insights into nonlocal phenomena in photonics and the functionality of the resulting *** a relevant example,we showcase STCMT’s flexibility by applying it to study and rapidly prototype nonlocal metasurfaces that spatially shape thermal emission.

关键词： theory resonant spatially