Articoli di riviste: "Doping"

1

ERTİN, Hakan, e Tayyibe BARDAKÇI. "Human Enhancement in Sports: The History of Doping and Anti-Doping". Turkiye Klinikleri Journal of Medical Ethics-Law and History 28, n. 1 (2020): 99–109. http://dx.doi.org/10.5336/mdethic.2019-71091.

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Primorac, Damir, Maja Buhovac e Nenad Miletić. "Istraživanje i dokazivanje dopinga kao sportskog delikta s osvrtom na kaznenopravni aspekt". Zbornik radova Pravnog fakulteta u Splitu 58, n. 1 (9 febbraio 2021): 185–209. http://dx.doi.org/10.31141/zrpfs.2021.58.139.185.

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O dopingu kao kažnjivoj radnji postoje različita teorijska stajališta i mišljenja. Jedni smatraju da se doping treba kažnjavati kaznenopravnim sankcijama, drugi da je dovoljna prekršajnopravna, a treći stegovna sankcija, kako bi se postigla svrha kažnjavanja. U našem pravnom sustavu borba protiv dopinga evoluirala je tako da danas imamo samodoping kao stegovno djelo koje se kažnjava prema pravilima proisteklima iz Svjetskog antidoping kodeksa. S druge strane, zakonodavac propisuje neovlaštenu proizvodnju i promet tvari zabranjenih u sportu kao zasebno kazneno djelo delicta communia, za koje se kažnjava, inter alia, onaj koji omogućava i stavlja na raspolaganje zabranjene tvari sportašu ili koji drugoga navodi na trošenje tih tvari, a to može biti i sam sportaš. Međutim, borba protiv dopinga ne uključuje samo materijalnopravno normiranje nego, štoviše, pitanja načina dokazivanja, otkrivanja i procesuiranja mogućih počinitelja. Stoga autori u ovom radu iznose procesnopravne odredbe kojima je regulirana borba protiv dopinga, što ukazuje na distinkcije koje postoje u pogledu pojedinih počinitelja ovog kaznenog/stegovnog djela. Doping je opasnost modernog svijeta koji se sastoji u prijevarnom postupanju počinitelja uzimanjem zabranjenih tvari radi postizanja vrhunskih rezultata. Pored toga što je nespojiv s etičkim načelima sporta, te što se uzimanjem dopinga može narušiti zdravlje sportaša, doping predstavlja delikt koji je potrebno sankcionirati. Pri tome, ostvariti punitivnu svrhu a ne utjecati negativno na ugled sporta, izazov je koji je stavljen i pred zakonodavca i pred sustav sporta općenito. Stoga borba protiv dopinga mora obuhvaćati sustavnu koordinaciju materijalnopravnih i postupovnih odredbi u cilju zaštite integriteta čistog sporta.

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Lee, Da Young, Da Eun Choi, Yejin Ahn, Hyojin Kye, Min Seon Kim e Bong-Gi Kim. "Sequential Cascade Doping of Conjugated-Polymer-Wrapped Carbon Nanotubes for Highly Electrically Conductive Platforms". Polymers 16, n. 13 (1 luglio 2024): 1884. http://dx.doi.org/10.3390/polym16131884.

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To explore a highly conductive flexible platform, this study develops PIDF-BT@SWCNT by wrapping single-walled carbon nanotubes (SWCNTs) with a conjugated polymer, PIDF-BT, known for its effective doping properties. By evaluating the doping behaviors of various dopants on PIDF-BT, appropriate dopant combinations for cascade doping are selected to improve the doping efficiency of PIDF-BT@SWCNT. Specifically, using F4TCNQ or F6TCNNQ as the first dopant, followed by AuCl3 as the second dopant, demonstrates remarkable doping efficiency, surpassing that of the individual dopants and yielding an exceptional electrical conductivity exceeding 6000 S/cm. Characterization using X-ray photoelectron spectroscopy and Raman spectroscopy elucidates the doping mechanism, revealing an increase in the proportion of electron-donating atoms and the ratio of quinoid structures upon F4TCNQ/AuCl3 cascade doping. These findings offer insights into optimizing dopant combinations for cascade doping, showcasing its advantages in enhancing doping efficiency and resulting electrical conductivity compared with single dopant processes.

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Elmar qızı Şahbazlı, Nəzrin. "Prohibited doping substances and methods, their definition. Doping control procedure". SCIENTIFIC WORK 65, n. 04 (21 aprile 2021): 147–50. http://dx.doi.org/10.36719/2663-4619/65/147-150.

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Doping by humans, both in competitions and on a daily basis, remains a major health problem in modern times. There are many growing body of evidences on the negative health effects of using doping. Doping-is the use of substances that will artificially increase their performance and harm the physical and psychological health of the athlete during a race or in preparation for a game. Worldwide doping controls are carried out in accordance with the Code and the International Standard for Testing (IST). Athletes who compete at the international and national level may be tested anytime, anywhere. Specially trained and accredited doping control personnel carry out all tests. The doping control procedure is clearly defined for all anti-doping organizations in the World Anti-Doping Agency (WADA) International Standard for Testing and Investigations (ISTI). Key words: doping substances, sports, harmful substance, fairplay, health, control of doping, methods of doping

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Tang, Chenqing, e Gongchun Li. "Impact of benzimidazole functional groups on the n-doping properties of benzimidazole derivatives". Open Chemistry 20, n. 1 (1 gennaio 2022): 840–48. http://dx.doi.org/10.1515/chem-2022-0202.

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Abstract n-Dopants play a crucial role in improving organic electronic devices through controlled doping of organic semiconductors. Benzimidazoline-based dopants have been reported as one of the best solution-processed n-type dopant precursors. In this study, two benzimidazoline-based dopants (BIBDTO and BBIBDTO) were prepared using benzo[1,2-b:4,5-b′]dithiophene as the 2-Ar unit, and their n-doping properties on the fullerene derivative PTEG-2 as the host material were carried out. For BIBDTO and BBIBDTO, respectively, the temperature at which 5% weight loss was achieved was 229 and 265°C. By comparing the ultraviolet-visible absorption spectroscopy, cyclic voltammetry, and density functional theory calculated data, it is found that BBIBDTO has a higher energy level, which is more favorable for charge transfer. Additionally, both the oxidative titration experiments and conductivity characterization of the dopants showed that BBIBDTO was more advantageous at low doping concentrations, and the BBIBDTO-doped PTEG-2 films obtained a conductivity of 0.15 S cm−1 at 10 mol% doping concentration. However, at high dopant concentrations, the dopant volume increases, potentially disrupting the microstructure. The highest conductivity of 0.29 S cm–1 was obtained at a BIBDTO doping concentration of 15 mol%. This study delves into the effect of benzimidazole functional groups on the doping performance of benzimidazoline-based dopant molecules, providing insight into designing novel efficient n-type dopant molecules and further selecting the type of dopant for various doping systems.

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Khlayboonme, S. Tipawan, e Warawoot Thowladda. "Synthesis and Characterization of Cu-Doped SnO₂ Thin Films by Aerosol Pyrolysis Technique for Gas Sensor Application". Key Engineering Materials 766 (aprile 2018): 205–10. http://dx.doi.org/10.4028/www.scientific.net/kem.766.205.

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Thin films of un-doped and Cu-doped tin oxide were synthesized on quartz substrates by the purpose-built aerosol pyrolysis apparatus from 0.2 M SnCl4.5H2O – ethanol solution. CuCl2.2H2O was used as a source of Cu dopant. The Cu dopant of 1, 3 and 5 wt.% were used for doping SnO2 film. The morphological, structural, optical and electrical properties under the influence of the Cu-doping was examined by FE-SEM, XRD, UV-Vis transmission spectroscopy and Hall effect measurement technique. XRD patterns of all films exhibited rutile-phase SnO2. The doping content of 1%Cu improved the film crystallinity. The Cu doping content decreased optical bandgap from 4.36 eV for undoped SnO2 to 4.28 eV for 3%Cu-doped SnO2. The further Cu doping content increased the bandgap energy to 4.32 eV. The resistivity was increased for doping of Cu 1% but it was decreased with further increasing in Cu-doping contents

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Liu, Bin, Mengzhen Li, Chunliang Yao, Minghan Cai, Guomeng Li, Hongyu Wang, Xiaoyu Gao, Xiujian Zhu e Wonjun Song. "11.2: The Effect of Doping Distribution on the Property of Green Phosphorescent Organic Light‐Emitting Diodes". SID Symposium Digest of Technical Papers 54, S1 (aprile 2023): 104–9. http://dx.doi.org/10.1002/sdtp.16233.

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In mass production OLED structures, doping ratio distribution across the thickness of emitting layer is not uniform owing to the linear evaporating configuration, where dopant and host materials are added in different sources. In this study, we firstly confirmed that different types of doping distribution among emitting layer of green phosphorescent OLED exhibited over 15% difference of current efficiency. By carefully designing and comparing emitting layers with a series of doping distribution modes, we found that dramatic variation of doping ratio near electron blocking layer was the critical factor. Then, trapping behavior of dopant molecules was confirmed to affect the carrier distribution among the emitting layer according to analysis of current density‐voltage (JV) and capacitance‐voltage (CV) curves from carrier only devices based on two types of doping distribution modes. Combining with the result of hole‐electron recombination zone (RZ), the area where possessed both high doping ratio and excitons recombination probability exhibited a high current efficiency and low driving voltage. Finally, PL and EL transient decay lifetime combined with triplet‐polaron quenching (TPQ) efficiency measurement demonstrated that TPQ was the main factor causing current efficiency difference between two types of doping distribution modes. Therefore, the doping distribution and trapping property of dopant material in emission layer should be carefully evaluated for OLED devices for mass production.

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Tammarugwattana, Narin, Kitipong Mano, Chaloempol Saributr, Adirek Rangkasikorn, Navaphun Kayunkid, Pitiporn Thanomngam e Jiti Nukeaw. "Growth and Characterizations of Tin-Doped on Nickel-Phthalocyanine as a Novel Nanomaterial". Advanced Materials Research 1131 (dicembre 2015): 39–42. http://dx.doi.org/10.4028/www.scientific.net/amr.1131.39.

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Tin-doped nickel phthalocyanine thin films (Sn-doped NiPc) were deposited by thermal co-evaporation method. Doping concentration of tin in NiPc was controlled via different deposition rates between metal dopent and host organic material. Properties of the thin films doped by tin in the range of 3 to 15% were characterized by atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), UV-Visible spectroscopy and X-ray photoelectron spectroscopy (XPS). Furthermore, electrical properties of Al/Sn-doped-NiPc/ITO devices i.e. charge carrier concentration and carrier mobility were characterized by current-voltage and capacitance-voltage measurements. Microscopic results show clear evidence of the morphological transition from granular structure in undoped-film to rod-liked structure in the films doped more than 5%. Moreover, surface grain size exhibits the tendency to decrease with the increase of doping concentration. Optical properties reveal that the packing of NiPc molecules in all doping conditions is the combination of α-phase (majority) and β-phase (minority). However, evolution of β-phase NiPc is observed with the increase of doping concentration. Photoelectron analyses indicate shift of binding energy in both Ni2p and Sn3d levels corresponding to charge transfer between nickel-core and tin dopant. In addition, the electrical properties show the enhancement of the film’s conductivity due to the increase of charge carrier concentration with the higher Sn-doping level.

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Wang, Kuan, Pengfei Yan, Zelin Wang, Junjie Fu, Zhenlu Zhang, Xiaoxing Ke e Manling Sui. "Advancing layered cathode material's cycling stability from uniform doping to non-uniform doping". Journal of Materials Chemistry A 8, n. 32 (2020): 16690–97. http://dx.doi.org/10.1039/d0ta05262k.

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Dopant segregation induced precipitates can further improve the cycling stability of a P2-layered cathode due to the precipitation strengthening effect, which conceptually validates that non-uniform doping has big advantage over uniform doping.

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Lu, Zhen Ya, Yu Xiang Liu, Zhi Wu Chen e Jian Qing Wu. "Effect of Ho₂O₃ Doping on Performance of ZnO Varistor". Key Engineering Materials 368-372 (febbraio 2008): 507–9. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.507.

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The effect of Ho2O3 doping on the electrical properties and microstructure of ZnO base varistor was investigated. It was found that Ho2O3 is an effective dopant for increasing the breakdown electric filed. The Ho2O3 doping can also improve the nonlinear performance both in low and high current area. But excessive doping of Ho2O3 will decrease the withstanding surge current. With 0.8mol% Ho2O3 doping, the varistor samples exhibit a breakdown voltage of about 400V/mm, a nonlinear coefficient of 80 and the withstanding surge current of 8/20μs, waveshape is higher than 5kA. Ho2O3 dopant can hinder ZnO grain growth and make the crystal grains more uniform.

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Wang, Ting, Yan Dong Mao, Fang Peng Tang, Jun Xing e Li Guang Wu. "Crystallization and Photocatalytic-Activity of TiO₂ Doped with Metal Ions Prepared by Adsorption Phase Synthesis". Advanced Materials Research 624 (dicembre 2012): 194–99. http://dx.doi.org/10.4028/www.scientific.net/amr.624.194.

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TiO2 photocatalysts doped with different metal ions were prepared by adsorption phase synthesis. The influence of different dopant metal ions with various concentrations on the crystallization of TiO2 was ex-plored by XRD. Then photodegradation experiments of methyl-orange were employed to evaluate the activity of these photocatalysts. The results indicated that the crystallization of TiO2 was restricted after doping, due to replacement of Ti4+ in TiO2 lattice structure by other metal ions. And the restriction became stronger with radius and concentration of doping ions increasing. There was an optimum dopant concentration appeared during preparation of TiO2 doped with Cd2+ and Fe3+. When dopant concentration was less or more than this optimum value, the photocatalytic activity of TiO2 doped with metal ions was lower than that of TiO2 without doping. Since radius of Fe3+ was close to Ti4+, the influence of Fe3+ dopant concentration on crystallization and activity of TiO2 was more obvious than that of Cd2+ doping.

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Daigo, Yoshiaki, Yuya Takada, Keisuke Kurashima, Toru Watanabe, Akio Ishiguro, Shigeaki Ishii, Yoshikazu Moriyama e Ichiro Mizushima. "Influence of residual dopants to net doping concentration in N-type 4H-SiC films grown using high-speed wafer rotation vertical CVD method". Japanese Journal of Applied Physics 61, SC (16 febbraio 2022): SC1041. http://dx.doi.org/10.35848/1347-4065/ac4c08.

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Abstract In this study, the influence of residual dopants on the net doping concentration in n-type 4H-SiC epitaxial films grown at different N2 flow rates and C/Si ratios were investigated. By reducing the N2 flow rate, the influence of the residual donors on the net doping concentration was observed to become dominant for the films grown at low C/Si ratios and that of the residual acceptors on the net doping concentration becomes dominant for the films grown at high C/Si ratios. For the films grown at the middle C/Si ratio, an apparent proportional relation due to the compensation balance between the residual and intentional donors and the residual acceptors was observed in the N2 flow rate dependence of the net doping concentration. Furthermore, the decay curve of the net doping concentration observed in the C/Si ratio dependence is affected by the compensation balance between the intentional dopant concentration and the residual dopant concentration.

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Kennedy, Noel, Ray Duffy, Luke Eaton, Dan O’Connell, Scott Monaghan, Shane Garvey, James Connolly, Chris Hatem, Justin D. Holmes e Brenda Long. "Phosphorus monolayer doping (MLD) of silicon on insulator (SOI) substrates". Beilstein Journal of Nanotechnology 9 (6 agosto 2018): 2106–13. http://dx.doi.org/10.3762/bjnano.9.199.

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This paper details the application of phosphorus monolayer doping of silicon on insulator substrates. There have been no previous publications dedicated to the topic of MLD on SOI, which allows for the impact of reduced substrate dimensions to be probed. The doping was done through functionalization of the substrates with chemically bound allyldiphenylphosphine dopant molecules. Following functionalization, the samples were capped and annealed to enable the diffusion of dopant atoms into the substrate and their activation. Electrical and material characterisation was carried out to determine the impact of MLD on surface quality and activation results produced by the process. MLD has proven to be highly applicable to SOI substrates producing doping levels in excess of 1 × 1019 cm−3 with minimal impact on surface quality. Hall effect data proved that reducing SOI dimensions from 66 to 13 nm lead to an increase in carrier concentration values due to the reduced volume available to the dopant for diffusion. Dopant trapping was found at both Si–SiO2 interfaces and will be problematic when attempting to reach doping levels achieved by rival techniques.

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DENG, ZEXIANG, JUNCONG SHE, ZHIBING LI, WEILIANG WANG e QIANG CHEN. "FIELD EVAPORATION OF GROUNDED ARSENIC DOPED SILICON CLUSTERS". Surface Review and Letters 22, n. 06 (20 ottobre 2015): 1550069. http://dx.doi.org/10.1142/s0218625x15500699.

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We have investigated the field evaporation of grounded arsenic (As) doped silicon (Si) clusters composed of 52 atoms with density functional theory (DFT) to mimic Si nano structures of hundreds of nanometers long standing on a substrate. Six cluster structures with different As doping concentrations and dopant locations are studied. The critical evaporation electric fields are found to be lower for clusters with higher doping concentrations and doping sites closer to the surface. We attribute the difference to the difference in binding energies corresponding to the different As-doping concentrations and to the doping locations. Our theoretical study could shed light on the stability of nano apexes under high electric field.

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Wang, Lin, Yuan Jun Sun, Jian Hai Luo, Yon Gan Zhu e Ping Wen Niu. "Influences of Doping Methods on Microstructure and Fracture Toughness of Mo-La Alloys". Materials Science Forum 534-536 (gennaio 2007): 1265–68. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.1265.

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Lanthanum oxide was introduced to molybdenum powder by liquid-liquid doping and liquid-solid doping respectively. Mo alloys were prepared by powder metallurgy technology. The size distribution and feature of dopant particles and the fractographs of Mo alloys were investigated by TEM and SEM respectively. The results indicated that liquid-liquid doping method is favorable for refining and dispersing La2O3 particles uniformly in matrix. Fracture toughness of Mo alloys prepared by liquid-liquid doping showed better results than that of liquid-solid doping. Furthermore, the influences of the size distribution of La2O3 on properties of Mo alloys was discussed by dislocation pile-up theory.

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Wang, F. M., Y. L. Li e C. L. Yan. "Microstructure, dielectric properties and phase transition of Y2O3-doped barium tin titanate ceramics". Digest Journal of Nanomaterials and Biostructures 19, n. 2 (6 giugno 2024): 785–91. http://dx.doi.org/10.15251/djnb.2024.192.785.

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BaCO3, SnO2 and TiO2 et al were used as crude materials, and Y2O3 was used as dopant, BaSnxTi1-xO3 (BTS) ceramics were prepared by solid-state reaction sintering technology. The results show that the doping of Y element does not change the lattice structure of barium tin titanate obviously, and there is no new phase, however, owing to the Y3+ ion doping, the diffraction peak position is changed as the Y3+ doping amount increasing. Interestingly, Curie temperature of the sample increased from 35 o C (blank sample) to 50 o C (0.05 mol%), and then the Curie temperature moved to low temperature as the doping amount increased continuously, which is related to the doping mechanism of Y3+ ion. After doping Y2O3, the dielectric loss of the samples decreases, especially when the doping amount reaches 0.10 mol%, the specimen shows excellent temperature stability of dielectric loss, making it superior candidates for applications.

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Kadam, Sunil R., Andrey N. Enyashin, Lothar Houben, Ronen Bar-Ziv e Maya Bar-Sadan. "Ni–WSe2 nanostructures as efficient catalysts for electrochemical hydrogen evolution reaction (HER) in acidic and alkaline media". Journal of Materials Chemistry A 8, n. 3 (2020): 1403–16. http://dx.doi.org/10.1039/c9ta10990k.

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Doping WSe₂ with various metals promotes the HER. Ni doping was found as the most efficient dopant, forming grafted layers on the structures. The mechanisms of the enhanced activity are unveiled and discussed.

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Virrisya, Virrisya, e Astuti Astuti. "Karakterisasi Sifat Optik Nanopartikel ZnO didoping Mn Menggunakan Metode Sol-Gel". Jurnal Fisika Unand 8, n. 4 (26 novembre 2019): 308–14. http://dx.doi.org/10.25077/jfu.8.4.308-314.2019.

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Karakterisasi sifat optik nanopartikel ZnO didoping Mn menggunakan metode sol-gel telah diteliti. Nanopartikel ZnO disintesis dengan variasi konsentrasi doping Mn sebesar 0%, 5%, 15%, 20%, dan 25%. Nanopartikel ZnO dikarakterisasi dengan X-Ray diffraction untuk diketahui struktur dan ukuran kristalnya. Struktur kristal nanopartikel ZnO yang didapatkan dari penelitian adalah hexagonal wurtzite dengan ukuran kristal untuk masing-masing variasi doping Mn berturut-turut yaitu 26,01 nm; 27,14 nm; 26,01 nm; 15,60 nm; dan 26,01 nm. UV-Vis spectrometry digunakan untuk karakterisasi celah pita energi dari nanopartikel ZnO. Nilai energi gap untuk masing-masing variasi konsentrasi doping Mn berturut-turut yaitu 3,03 eV; 2,71 eV; 2,56 eV; 2,5 eV dan 2,5 eV. Berdasarkan hasil penelitian, nilai energi gap nanopartikel ZnO semakin kecil dengan penambahan doping Mn. Karakterisasi sifat photoluminescence nanopartikel ZnO dilakukan dengan spectrometry photoluminescence, didapatkan 5 puncak emisi untuk seluruh variasi doping Mn yaitu dengan panjang gelombang, 349 nm, 361 nm, 395 nm, 423 nm dan 461 nm.Kata kunci: nanopartikel, ZnO, doping, sol-gel.

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Kim, Junho, Eui Hyun Suh, Kyumin Lee, Gyuri Kim, Hansu Kim, Jaeyoung Jang e In Hwan Jung. "Development of Alkylthiazole-Based Novel Thermoelectric Conjugated Polymers for Facile Organic Doping". Nanomaterials 13, n. 7 (6 aprile 2023): 1286. http://dx.doi.org/10.3390/nano13071286.

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In this study, we developed two novel conjugated polymers that can easily be doped with F4TCNQ organic dopants using a sequential doping method and then studied their organic thermoelectric (OTE) properties. In particular, to promote the intermolecular ordering of OTE polymers in the presence of the F4TCNQ dopant, alkylthiazole-based conjugated building blocks with highly planar backbone structures were synthesized and copolymerized. All polymers showed strong molecular ordering and edge-on orientation in the film state, even in the presence of the F4TCNQ organic dopant. Thus, the sequential doping process barely changed the molecular ordering of the polymer films while making efficient molecular doping. In addition, the doping efficiency was improved in the more π-extended polymer backbones with thienothiophene units due to the emptier space in the polymer lamellar structure to locate ionized F4TCNQ. Moreover, the study of organic thin-film transistors (OTFTs) revealed that higher hole mobility in OTFTs was the key to increasing the electrical conductivity of OTE devices fabricated using the sequential doping method.

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Jing, Ming Han, Jun Lin Yang, Yi Liu, Zheng Jing Zhao, Xiao Qian Wang, Jing Bo Li e Hai Bo Jin. "W-Nb Co-Doped VO<sub>2</sub> Films Realizing near Room-Temperature Transition and Satisfactory Thermochromic Performance for Smart Window". Materials Science Forum 1070 (13 ottobre 2022): 145–55. http://dx.doi.org/10.4028/p-rp934x.

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The W-Nb co-doped VO2 films are prepared through hydrothermal method. The effects of the Nb and W dopants are investigated respectively on the phase transition temperature (θc) and optical properties of VO2 by keeping the concentration of partner dopant at 1.0 at.%. The Nb doping induces a reduction of θc at a rate of ~ -13.0 °C per at.% Nb as Nb is less than ~1.5 at.%. For more than 1.5 at.% Nb, the θc shows a slight increase from ~23.0 °C. The W doping leads to a linear decrease of θc with a rate of ~ -17.2 °C per at.% W, more effective in reducing θc than the Nb dopant. However, the heavy W doping results in more serious deterioration of the solar energy modulation (ΔTsol) than the Nb doping. Therefore, taking use of the complementary advantages of W and Nb dopants, the 1.0 at.% W + 1.5 at.% Nb co-doped VO2 realizes the room-temperature transition at 23.0 °C with a satisfactory ΔTsol of ~9.6%, much better than the 1.5 at.% W + 1.0 at.% Nb co-doped which has a θc of ~22.1 °C and ΔTsol of ~5.3%. This work demonstrates the W-Nb co-doping is an effective doping formula in improving the performance of VO2 for smart window applications.

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Sarkar, S., E. Nefzaoui, G. Hamaoui, F. Marty, P. Basset e T. Bourouina. "Wideband mid infrared absorber using surface doped black silicon". Applied Physics Letters 121, n. 23 (5 dicembre 2022): 231703. http://dx.doi.org/10.1063/5.0117289.

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Black silicon (BSi) is a synthetic nanomaterial with high aspect ratio nano protrusions inducing several interesting properties such as a very large absorptivity of incident radiation. We have recently shown that heavily doping the BSi in volume enables to significantly enhance its mid-infrared absorptivity and tune its spectral range of interest up to 20 μm. In the present letter, we explore the effect of surface doping on BSi radiative properties and its absorptance in particular since surface doping enables reaching even larger dopant concentrations than volume doping but at more limited penetration depths. We considered 12 different wafers of BSi, fabricated with cryogenic plasma etching on n- and p-type silicon wafers and doped using ion-implantation with different dopant types, dosages, and ion beam energies, leading to different dopant concentrations and profiles. The different wafers radiative properties, reflectance, transmittance, and absorptance are experimentally measured using Fourier transform infrared spectroscopy. We show that doping an n-type BSi wafer with phosphorous with a dose of 1017 atm/cm2 and an energy of 100 keV increases its absorptivity up to 98% in the spectral range of 1–5 μm. We propose a simple phenomenological explanation of the observed results based on the dopant concentration profiles and the corresponding incident radiation penetration depth. Obtained results provide simple design rules and pave the way for using ion-implanted BSi for various applications, such as solar energy harvesting, thermo-photovoltaics, and infrared radiation sensing, where both high absorptance and variable dopant concentration profiles are required.

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Zhang, Xiwei, Jiansheng Jie, Xiujuan Zhang e Fengjun Yu. "Bismuth-catalyzed and doped p-type ZnSe nanowires and their temperature-dependent charge transport properties". Journal of Materials Chemistry C 4, n. 4 (2016): 857–62. http://dx.doi.org/10.1039/c5tc02853a.

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Simultaneous ZnSe nanowire growth and p-type doping is realized in one step by using Bi as the catalyst and dopant via chemical vapor deposition. Temperature-dependent electrical measurements are used for understanding the charge transport mechanism and the doping effect.

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Anbarasi, M., V. Nagarethinam e A. Balu. "Investigations on the structural, morphological, optical and electrical properties of undoped and nanosized Zn-doped CdS thin films prepared by a simplified spray technique". Materials Science-Poland 32, n. 4 (1 dicembre 2014): 652–60. http://dx.doi.org/10.2478/s13536-014-0244-7.

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AbstractCdS and Zn-doped CdS (CdS:Zn) thin films have been deposited on glass substrates by spray pyrolysis technique using a perfume atomizer. The influence of Zn incorporation on the structural, morphological, optical and electrical properties of the films has been studied. All the films exhibit hexagonal phase with (0 0 2) as preferential orientation. A shift of the (0 0 2) diffraction peak towards higher diffraction angle is observed with increased Zn doping. The optical studies confirmed that the transparency increases as Zn doping level increases and the film coated with 2 at.% Zn doping has the maximum transmittance of about 90 %. The sheet resistance (Rsh) decreases as the Zn-doping level increases and a minimum value of 1.113 × 103 Ω/sq is obtained for the film coated with 8 at.% Zn dopant. The CdS film coated with 8 at.% Zn dopant has the best structural, morphological and electrical properties.

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Tan, Changlong, Dianshuang Xu, Kun Zhang, Xiaohua Tian e Wei Cai. "Electronic and Magnetic Properties of Rare-Earth Metals Doped ZnO Monolayer". Journal of Nanomaterials 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/329570.

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The structural, electronic, and magnetic properties of rare-earth metals doped ZnO monolayer have been investigated using the first-principles calculations. The induced spin polarization is confirmed for Ce, Eu, Gd, and Dy dopings while the induced spin polarization is negligible for Y doping. The localizedfstates of rare-earth atoms respond to the introduction of a magnetic moment. ZnO monolayer undergoes transition from semiconductor to metal in the presence of Y, Ce, Gd, and Dy doping. More interestingly, Eu doped ZnO monolayer exhibits half-metallic behavior. Our result demonstrates that the RE-doping is an efficient route to modify the magnetic and electronic properties in ZnO monolayer.

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25

Birnbacher, D. "Doping und ärztliche Ethik". Deutsche Zeitschrift für Sportmedizin 2013, n. 03 (1 marzo 2013): 73–76. http://dx.doi.org/10.5960/dzsm.2012.060.

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26

Turski, Henryk, Pawel Wolny, Mikolaj Chlipala, Marta Sawicka, Anna Reszka, Pawel Kempisty, Leszek Konczewicz, Grzegorz Muziol, Marcin Siekacz e Czeslaw Skierbiszewski. "Role of Metallic Adlayer in Limiting Ge Incorporation into GaN". Materials 15, n. 17 (27 agosto 2022): 5929. http://dx.doi.org/10.3390/ma15175929.

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Atomically thin metal adlayers are used as surfactants in semiconductor crystal growth. The role of the adlayer in the incorporation of dopants in GaN is completely unexplored, probably because n-type doping of GaN with Si is relatively straightforward and can be scaled up with available Si atomic flux in a wide range of dopant concentrations. However, a surprisingly different behavior of the Ge dopant is observed, and the presence of atomically thin gallium or an indium layer dramatically affects Ge incorporation, hindering the fabrication of GaN:Ge structures with abrupt doping profiles. Here, we show an experimental study presenting a striking improvement in sharpness of the Ge doping profile obtained for indium as compared to the gallium surfactant layer during GaN-plasma-assisted molecular beam epitaxy. We show that the atomically thin indium surfactant layer promotes the incorporation of Ge in contrast to the gallium surfactant layer, which promotes segregation of Ge to the surface and Ge crystallite formation. Understanding the role of the surfactant is essential to control GaN doping and to obtain extremely high n-type doped III-nitride layers using Ge, because doping levels >1020 cm−3 are not easily available with Si.

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Qiu, Xinjia, Yingda Chen, Enze Han, Zesheng Lv, Zhiyuan Song e Hao Jiang. "High doping efficiency in p-type Al-rich AlGaN by modifying the Mg doping planes". Materials Advances 1, n. 1 (2020): 77–85. http://dx.doi.org/10.1039/d0ma00026d.

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Cai, Yan, e Jurgen Michel. "High n-Type Doping in Ge for Optical Gain and Lasing". Solid State Phenomena 205-206 (ottobre 2013): 394–99. http://dx.doi.org/10.4028/www.scientific.net/ssp.205-206.394.

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We review two ex-situ doping methods to achieve high n-type doping up to mid-1019 cm-3 in Ge-on-Si thin films. For both, delta doping and ion implantation, rapid thermal annealing is used to diffuse phosphorus from a diffusion source into the single crystal Ge layer. The diffusion mechanism is studied and we find that dopant enhanced diffusion in in-situ doped Ge attributes to the high doping level. A band gap narrowing effect is observed in highly doped n-type Ge through photoluminescence measurements by determining the photoluminescence peak shift. An empirical linear expression of the direct band gap narrowing shift with carrier concentration is proposed.

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Abass, Hawraa Hadi, e Bushra A. Hasan. "Impact of Aluminum Oxide Content on the Structural and Optical Properties of ZnO: AlO Thin Films". Iraqi Journal of Physics (IJP) 19, n. 51 (1 dicembre 2021): 41–53. http://dx.doi.org/10.30723/ijp.v19i51.685.

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AlO-doped ZnO nanocrystalline thin films from with nano crystallite size in the range (19-15 nm) were fabricated by pulsed laser deposition technique. The reduction of crystallite size by increasing of doping ratio shift the bandgap to IR region the optical band gap decreases in a consistent manner, from 3.21to 2.1 eV by increasing AlO doping ratio from 0 to 7wt% but then returns to grow up to 3.21 eV by a further increase the doping ratio. The bandgap increment obtained for 9% AlO dopant concentration can be clarified in terms of the Burstein–Moss effect whereas the aluminum donor atom increased the carrier's concentration which in turn shifts the Fermi level and widened the bandgap (blue-shift). The engineering of the bandgap by low concentration of AlO dopant makes ZnO: AlO thin films favorable for the fabrication of optoelectronic devices. The optical constants were calculated and was found to be greatly affected by the increasing the doping ratio.

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Xu, Xiao Ling, Dan Chen, Xing Duan, Zhi Gang Yi e Zuo Wan Zhou. "Post-Doping of ZnO with Cu and its Effect on their Photocatalytic Production of Active Oxygen Species". Advanced Materials Research 197-198 (febbraio 2011): 853–56. http://dx.doi.org/10.4028/www.scientific.net/amr.197-198.853.

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Cu doping zinc oxides (ZnOs) were prepared by a post doping process with CuCl2 at high temperature. With the increase of the dopant loading, the lattice constant c decreased firstly and then increased, which indicated that the doped Cu atoms substituted for Zn atoms at lower loading and extra dopant of the Cu atoms existed as interstitial atoms. UV-Vis diffuse reflectance spectra (UV-DRS) illustrated that the energy band gap was effectively narrowed after Cu doping. The photocatalytic production of hydroxyl radical (•OH) and superoxide anion (O2-) were determined by terephthalic acid with fluorescence spectrophotometer and nitroblue tetrazolium with UV-Vis spectrophotometer respectively, and the results showed that both the photocatalytic production of •OH and O2- were deceased with the increase of the dopant concentration, which indicated that the recombination centers were formed in the samples.

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31

Kuru, Cihan, Mirac Alaf e Yunus E. Simsek. "Effect of Vanadium Doping on the Catalytic Activity of MoO2 Thin Films in Hydrogen Evolution Reaction". Journal of Nanoscience and Nanotechnology 20, n. 9 (1 settembre 2020): 5533–38. http://dx.doi.org/10.1166/jnn.2020.17854.

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Recently, Mo-based materials have emerged as promising candidates to replace Pt catalysts for hydrogen evolution reaction. Among these, MoO2 holds a great promise due to its metallic conductivity. Here, we investigate the effect of V doping on the hydrogen evolution reaction activity of MoO2 thin films. V doped MoO2 thin films with different dopant concentrations were prepared on conductive Si substrates by co-sputtering followed by thermal sulfurization. The electrochemical measurements revealed that V doping has an adverse effect on the hydrogen evolution reaction performance of MoO2 films, attributed to the p-type doping nature of V. This study gives insight into the effect of dopant type on the catalytic activity of hydrogen evolution reaction catalysts and provides a hint for the correct selection of dopant elements to enhance the activity of the existing catalyst materials.

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32

Li, Jinhang, Jiawei Chen, Leimeng Xu, Sinan Liu, Si Lan, Xiansheng Li e Jizhong Song. "A zinc non-halide dopant strategy enables efficient perovskite CsPbI3 quantum dot-based light-emitting diodes". Materials Chemistry Frontiers 4, n. 5 (2020): 1444–53. http://dx.doi.org/10.1039/c9qm00734b.

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A zinc non-halide dopant strategy is employed to clarify the internal mechanism of Zn²⁺ doping without the introduction of halide ions and enhance the emission properties evidenced by the EQE of the QLEDs from 7.5% to 14.6% after Zn²⁺ doping.

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33

Chen, Chang-Yuan, Cheng-Chih Hsu, Chyan-Chyi Wu e Ching-Liang Dai. "Sodium Chloride Concentration Measurement by Using Doping/Un-doping Poly-silicon Nanowire Device". International Journal of Materials Science and Engineering 6, n. 1 (marzo 2018): 18–22. http://dx.doi.org/10.17706/ijmse.2018.6.1.18-22.

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34

Chen, Hungru, e Naoto Umezawa. "Sensitization of Perovskite Strontium Stannate SrSnO3towards Visible-Light Absorption by Doping". International Journal of Photoenergy 2014 (2014): 1–3. http://dx.doi.org/10.1155/2014/643532.

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Perovskite strontium stannate SrSnO3is a promising photocatalyst. However, its band gap is too large for efficient solar energy conversion. In order to sensitize SrSnO3toward visible-light activities, the effects of doping with various selected cations and anions are investigated by using hybrid density functional calculations. Results show that doping can result in dopant level to conduction band transitions which lie lower in energy compared to the original band gap transition. Therefore, it is expected that doping SrSnO3can induce visible-light absorption.

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35

Azər qızı Abuzərli, Nərmin. "International mechanisms in the fields of fight against doping and the Azerbaijan Republic". SCIENTIFIC WORK 77, n. 4 (17 aprile 2022): 258–63. http://dx.doi.org/10.36719/2663-4619/77/258-263.

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Məqalə idman oyunları zamanı sağlamlığın təmini, mədəni, mənəvi və fiziki tərbiyənin təşkili kontekstində dopinqin qadağan olunması sahəsində beynəlxalq müqavilə və institusional mexanizmlərin fəaliyyəti, habelə bu əməkdaşlıq prosesində Azərbaycan Respublikasının iştirakına toxunmuşdur. Həmçinin, Beynəlxalq Cinayət Polisi Təşkilatı – İNTERPOL çərçivəsində aparılan əməliyyatlar və onların əhəmiyyəti, eləcə də BMT-nin BMT-nin Narkotik və Cinayətkarlığa Qarşı Mübarizə İdarəsinin müvafiq sahədə fəaliyyəti də nəzərdən keçirilmişdir. Açar sözlər: dopinq, idman, Azərbaycan Milli Antidopinq Agentliyi, Ümumdünya Antidopinq Agentliyi, Ümumdünya Antidopinq Məcəlləsi, YUNESKO, Avropa Şurası, İNTERPOL, Beynəlxalq Test Agentliyi Narmin Azar Abuzarli International mechanisms in the fields of fight against doping and the Azerbaijan Republic Abstract The article touched upon the activities of international treaties and institutional mechanisms in the field of doping control in the context of ensuring health, cultural, spiritual and physical education during sports games, as well as the participation of the Republic of Azerbaijan in this cooperation process. The operations carried out within the framework of the International Criminal Police Organization - INTERPOL and their importance, as well as the activities of the UN Office on Drugs and Crime in the relevant field were also considered. Key words: doping, sports games, Azerbaijan National Anti-Doping Agency, World Anti-Doping Agency, World Anti-Doping Code, UNESCO, Council of Europe, INTERPOL, International Testing Agency

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36

Anisa, S. D. N., F. Nurosyid, Y. Iriani, N. D. Puspitasari e U. Riyadi. "Doping of magnesium and aluminum ions on tio₂ as photoanode using the doctor blade method to increase dssc efficiency". Journal of Physics: Conference Series 2556, n. 1 (1 agosto 2023): 012020. http://dx.doi.org/10.1088/1742-6596/2556/1/012020.

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Abstract Titanium dioxide (TiO2) is the most commonly used photoanode material for working electrodes in DSSC. TiO2 was chosen because of its stable performance. The electron transport process in the pores of TiO2 nanoparticles occurs randomly. Thus, it will cause a charge recombination process, decreasing the device’s performance. TiO2 needs to be modified by the addition of doping. The dopings used in this study are magnesium and aluminum ions with varying concentrations of 4%, 5%, and 6% using the doctor blade method. The characterizations carried out include absorbance and bandgap with UV-Vis Spectrophotometer, Morphology with SEM, and efficiency of DSSC with I-V Keithley Meter. The results of UV-Vis characterization obtained the highest absorbance peak when Al and Mg-doped in the wavelength range (250-600) nm. The band gap energy value is at 5% concentration of Mg doping in 1.9 eV and 5% doping of Al concentration in 2.4 eV. The results of the SEM test showed that morphological results obtained greater agglomeration along with the addition of doping. Efficiency results were obtained when doping Al concentrations of 4%, 5%, 6% respectively are 0.205%, 0.415%, 0.275% and when doping of Mg concentrations are 4%, 5%, 6% respectively 0.03%, 0 0.06%, 0.018%.

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37

Zhang, Siyuan, Hsun Jen Chuang, Son T. Le, Curt A. Richter, Kathleen M. McCreary, Berend T. Jonker, Angela R. Hight Walker e Christina A. Hacker. "Control of the Schottky barrier height in monolayer WS₂ FETs using molecular doping". AIP Advances 12, n. 8 (1 agosto 2022): 085222. http://dx.doi.org/10.1063/5.0101033.

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Developing controllable doping processes for two-dimensional (2D) semiconductors is critical to developing next-generation electronic and optoelectronic devices. Understanding the nature of the contacts is an essential step in realizing efficient charge injection in transition metal dichalcogenides. In this study, post-growth n-doping of chemical vapor deposition grown monolayer (1 L) WS2 is achieved through molecular reductant solution treatment. The doping level can be effectively controlled by the treatment time and dopant solution concentrations. The doped WS2 field-effect transistors showed profound threshold voltage shifts and tunable channel currents. This molecular n-doping technique is beneficial for the selective area doping needed for electrical contacts and reduces the contact resistance ( Rc) in 1 L WS2 by more than two orders of magnitude. The significant reduction of Rc is attributed to the high electron-doping density achieved in WS2, which leads to a significant reduction of the Schottky barrier height. The dependence of mobility on temperature indicates clear evidence of the strong suppression of charge-impurity scattering after doping. High levels of doping allow the observation of a metal–insulator transition in monolayer WS2 due to strong electron–electron interactions. This doping technique provides a viable route for tailoring the electrical properties and improving the contacts in transition metal dichalcogenides, paving the way for high-performance 2D nanoelectronic devices.

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38

Kaphle, Amrit, Travis Reed, Allen Apblett e Parameswar Hari. "Doping Efficiency in Cobalt-Doped ZnO Nanostructured Materials". Journal of Nanomaterials 2019 (24 aprile 2019): 1–13. http://dx.doi.org/10.1155/2019/7034620.

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Nanostructured ZnO thin films doped with cobalt from 5% to 20% were grown on glass substrates by a low-temperature chemical bath deposition (CBD) technique. We compared the doping efficiency of incorporating cobalt in ZnO nanostructured samples doped with cobalt via cobalt nitrate and cobalt chloride. The concentration of cobalt incorporated into the ZnO matrix was precisely determined using inductively coupled plasma mass spectroscopy (ICP-MS). Scanning electron microscopy (SEM) images showed that only at a 0.1 M ratio of the precursor solutions in CBD using cobalt nitrate as a dopant, the morphology of ZnO yielded hexagonally shaped nanorods. At a 1 M ratio of the precursor solutions, SEM images showed that the morphology of ZnO was nanoplatelets at all doping levels, irrespective of the doping method used. The synthesized nanostructures retained the wurtzite hexagonal structure only at 0.1 M precursor solution using cobalt nitrate doping, which was confirmed by X-ray diffraction (XRD) studies. In cobalt-doped samples using cobalt chloride as a dopant, XRD analysis confirmed the formation of a Simonkolleite structure. At 300°C, the Simonkolleite structure was converted to a wurtzite structure without changing the morphology. Electrical conductivity measurements at 300 K showed that ZnO nanorods doped with cobalt using cobalt nitrate yielded the lowest resistivity. The molarity of the precursor solution and dopant was found to have a substantial impact on the morphology and doping efficiency of the ZnO nanostructures.

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Filipowski, Wojciech, Kazimierz Drabczyk, Edyta Wróbel, Piotr Sobik, Krzysztof Waczynski e Natalia Waczynska-Niemiec. "Borosilicate spray-on glass solutions for fabrication silicon solar cell back surface field". Microelectronics International 35, n. 3 (2 luglio 2018): 172–76. http://dx.doi.org/10.1108/mi-12-2017-0075.

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Purpose The purpose of this paper is to develop a method of preparing spray-on dopant solutions that enable obtaining a p+ region forming a back-surface field (BSF) during the diffusion doping process. The spray-on method used allows to decrease the costs of dopant solution application, which is particularly significant for new low-cost production processes. Design/methodology/approach This paper presents steps of production of high concentration boron dopant solutions enabling diffusion doping of crystalline p-type silicon surfaces. To check the fabricated dopant solutions for stability and suitability for spray-on application, their viscosity and density were measured in week-long intervals. The dopant solutions described in this paper were used in a series of diffusion doping processes to confirm their suitability for BSF production. Findings A method of preparing dopant solutions with parameters enabling depositing them on silicon wafers by the spray-on method has been established. Due to hygroscopic properties of the researched dopant solutions, a maximum surrounding atmosphere humidity has been established. The solutions should not be applied by the spray-on method, if this humidity value is exceeded. The conducted derivatographic examination enabled establishing optimal drying conditions. Originality/value The paper presents a new composition of a dopant solution which contains high concentration of boron and may be applied by the spray-on method. Derivatographic examination results, as well as equations describing the relation between dopant solution density and viscosity and storage time are also original for this research. The established dependencies between the sheet resistance of the fabricated BSF and the diffusion doping time are other new elements described in the paper.

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40

Moraru, Daniel, Arup Samanta, Takahiro Tsutaya, Yuki Takasu, Takeshi Mizuno e Michiharu Tabe. "Tunneling Transport in Quantum Dots Formed by Coupled Dopant Atoms". Advanced Materials Research 1117 (luglio 2015): 78–81. http://dx.doi.org/10.4028/www.scientific.net/amr.1117.78.

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In silicon nanoscale transistors, dopant (impurity) atoms can significantly affect transport characteristics, in particular at low temperatures. Coupling of neighboring dopants in such devices is essential in defining the properties for transport. In this work, we briefly present a comparison of different regimes of inter-dopant coupling, controlled by doping concentration and, to some extent, by selective, local doping. Tunneling-transport spectroscopy can reveal the energy spectrum of isolated dopants and of strongly-coupled dopant atoms. Interactions of multiple-dopants quantum dots (QDs) and satellite individual dopant-traps, as observed in some devices, can provide further information to bridge such inter-dopant coupling regimes for more advanced applications.

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41

Liu, Qiang, Marcin Zając, Małgorzata Iwińska, Shuai Wang, Wenrong Zhuang, Michał Boćkowski e Xinqiang Wang. "Carbon doped semi-insulating freestanding GaN crystals by ethylene". Applied Physics Letters 121, n. 17 (24 ottobre 2022): 172103. http://dx.doi.org/10.1063/5.0118250.

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Semi-insulating freestanding GaN crystals are excellent candidates for substrates of GaN-based power electronic devices. Carbon doping is believed to be currently the optimal way to achieve semi-insulating GaN crystals grown by halide vapor phase epitaxy (HVPE). Here, we demonstrate that ethylene is an excellent source for C doping, where the doping efficiency is much higher than that of methane. Under the same carbon mole flux, the carbon incorporation rate of ethylene is 40 times in magnitude higher than that of methane. A record highest resistivity is achieved by ethylene doping with a carbon concentration of 1.5 × 1020 cm−3. Our work demonstrates that ethylene is an excellent carbon dopant source for HVPE-grown GaN crystals.

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42

Hoppeler, Hans H., Matthias F. Kamber e Paul S. Melia. "Doping and Prevention of Doping". Clinical Journal of Sport Medicine 5, n. 2 (aprile 1995): 79–81. http://dx.doi.org/10.1097/00042752-199504000-00001.

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43

Buzzi, Elisa. "Doping tradizionale e doping genetico: questioni etiche / Traditional doping and genetic doping: ethical issues". Medicina e Morale 67, n. 1 (23 marzo 2018): 41–54. http://dx.doi.org/10.4081/mem.2018.527.

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Il complesso fenomeno del doping presenta notevoli problemi di definizione. Queste difficoltà, che hanno influenzato l’evoluzione delle politiche anti-doping, sono ulteriormente acuite dall’assenza di una cornice etica chiaramente definita, in grado di giustificare inequivocabilmente le azioni di contrasto intraprese dalle agenzie sportive a partire dalla seconda metà del XX secolo. Ai problemi di interpretazione del doping nelle sue forme tradizionali si sono aggiunte, da qualche decennio, le questioni relative al doping genetico. Il contributo analizza le diverse tipologie di tecnologia genetica, potenzialmente utilizzabili per un miglioramento della prestazione atletica, nella prospettiva di una valutazione etica. Oltre ai problemi medici, legali e morali del doping tradizionale, il doping genetico pone dilemmi etici inediti che rischiano di rendere le risposte dell’etica sportiva e delle politiche anti-doping, se non inefficaci, per lo meno inadeguate e anacronistiche. Nonostante la difficoltà di prevedere l’impatto che le tecnologie genetiche potranno avere sul mondo dello sport, la prospettiva del doping genetico, non diversamente da altre forme di doping, ma più radicalmente, pone due tipi di questioni. In primo luogo, costringe a ripensare alla natura e alle finalità dello sport e delle competizioni atletiche come espressioni dell’eccellenza umana. In secondo luogo, solleva questioni fondamentali circa la definizione dell’identità e della dignità umane nella civiltà tecnologica. ---------- Interpreting doping is fraught with difficulties at the very level of a comprehensive and consistent definition of the phenomenon. Such difficulties have influenced the evolution of anti-doping policies, that are further hindered by the lack of a clearly articulated ethical framework. Moreover, in the last few decades, a host of moral dilemmas has been arising in connection with gene doping. This article analyses different kinds of genetic technology that could enhance athletic performances in the light of their moral implications. In addition to the medical, legal, and ethical problems inherent in traditional doping, gene doping raises a whole range of new ethical issues that might render the current formulations of sport ethics and anti-doping policies, if not ineffectual, at least inadequate and anachronistic. Notwithstanding the difficulties in foreseeing how developments in genetic technology might impact the world of sport in the future, the perspective of gene doping radicalises two kinds of issues, that are not stranger to other forms of doping. Firstly, it leads to reconsider the nature and goals of sport as an expression of human excellency, and secondly, it raises fundamental questions about the definition of human identity and dignity in a technological civilization.

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El-Shobaky, Gamil A., Nagi R. E. Radwan e Farouk M. Radwan. "Catalytic Decomposition of H2O2 over Pure and Li2O-Doped Co3O4 Solids". Adsorption Science & Technology 16, n. 9 (ottobre 1998): 733–46. http://dx.doi.org/10.1177/026361749801600906.

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Pure and doped Co3O4 samples were prepared by the thermal decomposition at 500–900°C of pure and lithium nitrate-treated basic cobalt carbonate. The amounts of dopant added were varied in the range 0.75–6 mol% Li2O. The effects of this treatment on the surface and catalytic properties of cobaltic oxide solid were investigated using nitrogen adsorption at −196°C and studies of the decomposition of H2O2 at 30–50°C. The results obtained revealed that Li2O doping of Co3O4 followed by heat treatment at 500°C and 600°C resulted in a progressive increase in the value of the specific surface area, SBET, to an extent proportional to the amount of dopant present. However, the increase was more pronounced in the case of solid samples calcined at 500°C. This increase in the specific surface areas has been attributed to the fixation of a portion of the dopant ions on the uppermost surface layers of the solid leading to outward growth of the surface lattice. The observed increase in SBET due to Li2O doping at 500°C might also result from a narrowing of the pores in the treated solid as a result of the doping process. Lithium oxide doping of cobaltic oxide followed by heat treatment at 700–900°C resulted in a significant decrease in the SBET, Vp and r̄ values. Pure and doped solids precalcined at 500°C and 600°C exhibited extremely high catalytic activities which were not much affected by doping with Li2O. On the other hand, doping followed by calcination at 700–900°C brought about a considerable and progressive increase in the catalytic activity of the treated solids. This treatment did not modify the activation energy of the catalysed reaction, i.e. doping of Co3O4 solid followed by heating at 700°C and 900°C did not alter the mechanism of the catalytic reaction but increased the concentration of catalytically active constituents taking part in the catalytic process without altering their energetic nature.

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Direksilp, Chatrawee, e Anuvat Sirivat. "Synthesis and Characterization of Hollow-Sphered Poly(N-methyaniline) for Enhanced Electrical Conductivity Based on the Anionic Surfactant Templates and Doping". Polymers 12, n. 5 (1 maggio 2020): 1023. http://dx.doi.org/10.3390/polym12051023.

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Poly(N-methylaniline) (PNMA) is a polyaniline derivative with a methyl substituent on the nitrogen atom. PNMA is of interest owing to its higher solubility in organic solvents when compared to the unsubstituted polyaniline. However, the electrical conductivity of polyaniline derivatives suffers from chemical substitution. PNMA was synthesized via emulsion polymerization using three different anionic surfactants, namely sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and dioctyl sodium sulfosuccinate (AOT). The effects of surfactant structures and concentrations on electrical conductivity, doping level, crystallinity, morphology, and thermal stability were investigated. The re-doping step using perchloric acid (HClO4) as a dopant was sequentially proceeded to enhance electrical conductivity. PNMA synthesized in SDBS at five times its critical micelle concentration (CMC) demonstrated the highest electrical conductivity, doping level, and thermal stability among all surfactants at identical concentrations. Scanning electron microscopy (SEM) images revealed that the PNMA particle shapes and sizes critically depended on the surfactant types and concentrations, and the doping mole ratios in the re-doping step. The highest electrical conductivity of 109.84 ± 20.44 S cm−1 and a doping level of 52.45% were attained at the doping mole ratio of 50:1.

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46

YARLAGADDA, SUDHAKAR, e C. S. TING. "MEAN-FIELD APPROACH TO CHARGE, ORBITAL, AND SPIN ORDERING IN MANGANITES". International Journal of Modern Physics B 15, n. 19n20 (10 agosto 2001): 2719–26. http://dx.doi.org/10.1142/s021797920100646x.

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We present a mean-field theory of charge, orbital, and spin ordering in manganites at 50% and 0% dopings by considering Jahn–Teller interaction, nearest-neighbor repulsion, and no single-site double occupancy. For spinless fermions, we show that Jahn–Teller distortion and charge-orbital ordering occur simultaneously. In our two-dimensional model at 50% doping, for small nearest-neighbor repulsion the system is orbitally polarized while for larger repulsion the system undergoes CE type ordering. As for the 0% doping case, the ground state is orbitally antiferromagnetic. Upon including spin degree of freedom, at both 50% and 0% dopings the ordering remains the same at small antiferromagnetic coupling between adjacent core spins.

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47

Zhang, Kaijian, Wei Xu, Xinjun Li, Shaojian Zheng e Gang Xu. "Effect of dopant concentration on photocatalytic activity of TiO2 film doped by Mn non-uniformly". Open Chemistry 4, n. 2 (1 giugno 2006): 234–45. http://dx.doi.org/10.2478/s11532-006-0010-8.

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AbstractThe thin films of TiO2 doped by Mn non-uniformly were prepared by sol-gel method under process control. In our preceding study, we investigated in detail, the effect of doping mode on the photocatalytic activity of TiO2 films showing that Mn non-uniform doping can greatly enhance the activity. In this study we looked at the effect of doping concentration on the photocatalytic activity of the TiO2 films. In this paper, the thin films were characterized by UV-vis spectrophotometer and electrochemical workstation. The activity of the photocatalyst was also evaluated by photocatalytic degradation rate of aqueous methyl orange under UV radiation. The results illustrate that the TiO2 thin film doped by Mn non-uniformly at the optimal dopant concentration (0.7 at %) is of the highest activity, and on the contrary, the activity of those doped uniformly is decreased. As a comparison, in 80 min, the degradation rate of methyl orange is 62 %, 12 % and 34 % for Mn non-uniform doping film (0.7 at %), the uniform doping film (0.7 at %) and pure titanium dioxide film, respectively. We have seen that, for the doping and the pure TiO2 films, the stronger signals of open circuit potential and transient photocurrent, the better photocatalytic activity. We also discusse the effect of dopant concentration on the photocatalytic activity of the TiO2 films in terms of effective separation of the photon-generated carriers in the semiconductor.

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48

ÇELİK, Buse, Zehra CERTEL, Ziya BAHADIR e Melek MAKARACI. "Bireysel Spor Dallarıyla Uğraşan Antrenör ve Sporcuların Doping Bilgi Düzeylerinin ve Düşüncelerinin Karşılaştırılması". Uluslararası Türk Spor ve Egzersiz Psikolojisi Dergisi, 31 dicembre 2022. http://dx.doi.org/10.55376/ijtsep.1226862.

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Bu çalışmada, bireysel spor dallarıyla uğraşan antrenörlerin ve sporcuların doping bilgi düzeylerinin ve düşüncelerinin karşılaştırılması amaçlanmıştır. Araştırma betimsel tarama modelindedir. Araştırmanın örneklemini, Antalya’da açılan 1. Kademe Okçuluk ve Vücut Geliştirme/Fitness Antrenörlük Kursuna katılan sporcular (n=154) ile Türkiye Muaythai Federasyonu tarafından Antalya’da yapılan Hakem-Antrenör Gelişim ve Vize Seminerine katılan antrenörler (n=171) olmak üzere 325 kişi oluşturmaktadır. Araştırmada veri toplama aracı olarak, Sargın (2007) tarafından geliştirilen “Dopingle İlgili Bilgi Düzeyi ve Düşünce Anketi” ile araştırmacı tarafından hazırlanan kişisel bilgi formu kullanılmıştır. Elde edilen veriler SPSS 18.0 istatistik programında değerlendirilmiş, verilerin analizde yüzde ve frekans değerleri ile ki-kare testi kullanılmıştır. Antrenörlerin tamamına yakını dopingin kesinlikle kullanılmaması gerektiğini, spor ahlakına aykırı ve haksız rekabete neden olduğunu ifade etmişlerdir. Sporcuların ise %22.7’si dopingin gerekirse kullanılması gerektiği cevabını vermiştir. Sporcuların %36’sı sporcuların genellikle doping çeşitlerinden uyarıcıları, antrenörlerin %29’u sporcuların genellikle doping çeşitlerinin hepsini kullandıklarını belirtmişlerdir. Antrenör ve sporcular, sporcuların doping kullanmasındaki psikolojik sebebin aşırı kazanma hırsı olduğunu ve kullanan sporcuya 1-2 yıl yarışma cezası verilmesi gerektiğini ifade etmişlerdir. “Başarılı olmak için her yolu denerim düşüncesine sahip misiniz?”, “Doping kullanımının fair play (centilmenlik) ruhuna zarar verdiğini düşünüyor musunuz?”, “Sizce doping kullanılmaması ( anti doping ) konusunda devletin etkili bir politikası var mı?”, “Çevrenizde doping yapan sporcu veya sporcular var mı?”, “Sporda doping kullanımının başarıyı ve performansı olumlu etkileyeceğini düşünüyor musunuz?”, “Sizce doping kullanımı serbest bırakılmalı mı?”, “Gen dopingi olarak tabir edilen yöntem sizce doping sınıflamasına girmeli mi?”, “Sporcu yakalanmadığı sürece ilaç ( doping) kullanabilir” ve “Doping yaptığı belirlenen bir sporcuya ülkesi sahip çıkmalı” ifadelerine verdikleri cevaplarda antrenör ve sporcular arasında istatistiksel olarak anlamlı farklılıklar bulunmuştur (p

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49

Mone, S., W. Zagozdzon-Wosik e M. Rastogi. "Surface Effects in Silicon Doping with Boron During Proximity Rapid Thermal Diffusion". MRS Proceedings 405 (1995). http://dx.doi.org/10.1557/proc-405-351.

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AbstractWe investigated effects of surface preparation in doping silicon wafers using proximity rapid thermal diffusion (RTD). This process uses a spin-on-dopant (SOD) as an evaporating source for doping processed wafers. Various cleaning processes were used to study formation of the dopant glass on the silicon wafers during RTD. Doping was evaluated by sheet resistance measurements, dopant profiling using SIMS analyses, carrier distributions using spreading resistance profiling (SRP) or anodic oxidation, and was complemented by the composition analyses of the SOD deposited on the source wafers and of the dopant glass formed on the target wafers using Fourier Transform Infrared Spectroscopy (FTIR) in the transmission and reflection modes, respectively. It was found that the influence of the cleaning steps is much stronger in low temperature doping processes than at high temperatures. In addition, the temperature effect related to the wafer size was also an important factor in determining the doping efficiency in this RTDs.

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50

Verma, Archana, e Nicholas E. Jackson. "Assessing molecular doping efficiency in organic semiconductors with reactive Monte Carlo". Journal of Chemical Physics 160, n. 10 (11 marzo 2024). http://dx.doi.org/10.1063/5.0197816.

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The addition of molecular dopants into organic semiconductors (OSCs) is a ubiquitous augmentation strategy to enhance the electrical conductivity of OSCs. Although the importance of optimizing OSC–dopant interactions is well-recognized, chemically generalizable structure–function relationships are difficult to extract due to the sensitivity and dependence of doping efficiency on chemistry, processing conditions, and morphology. Computational modeling for an integrated OSC–dopant design is an attractive approach to systematically isolate fundamental relationships, but requires the challenging simultaneous treatment of molecular reactivity and morphology evolution. We present the first computational study to couple molecular reactivity with morphology evolution in a molecularly doped OSC. Reactive Monte Carlo is employed to examine the evolution of OSC–dopant morphologies and doping efficiency with respect to dielectric, the thermodynamic driving for the doping reaction, and dopant aggregation. We observe that for well-mixed systems with experimentally relevant dielectric constants, doping efficiency is near unity with a very weak dependence on the ionization potential and electron affinity of OSC and dopant, respectively. At experimental dielectric constants, reaction-induced aggregation is observed, corresponding to the well-known insolubility of solution-doped materials. Simulations are qualitatively consistent with a number of experimental studies showing a decrease of doping efficiency with increasing dopant concentration. Finally, we observe that the aggregation of dopants lowers doping efficiency and thus presents a rational design strategy for maximizing doping efficiency in molecularly doped OSCs. This work represents an important first step toward the systematic integration of molecular reactivity and morphology evolution into the characterization of multi-scale structure–function relationships in molecularly doped OSCs.

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