Journal articles: 'Vertical charge transfer'

1

Kazemi, Alireza, Sam Vaziri, Jorge Daniel Aguirre Morales, Sébastien Frégonèse, Francesca Cavallo, Marziyeh Zamiri, Noel Dawson, et al. "Vertical Charge Transfer and Lateral Transport in Graphene/Germanium Heterostructures." ACS Applied Materials & Interfaces 9, no. 18 (April 28, 2017): 15830–40. http://dx.doi.org/10.1021/acsami.7b01424.

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Panchishkina, I. N., G. G. Petrova, and A. I. Petrov. "Experimental study of charge vertical transfer in surface air layer." Geomagnetism and Aeronomy 57, no. 3 (May 2017): 347–51. http://dx.doi.org/10.1134/s0016793217030124.

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Huang, Zhaoming, Zhe Deng, Yue Shen, Wanqi Chen, Wei Liu, Meilan Xie, Yankai Li, and Yunhui Huang. "A Li–O2 battery cathode with vertical mass/charge transfer pathways." Journal of Materials Chemistry A 7, no. 7 (2019): 3000–3005. http://dx.doi.org/10.1039/c9ta00017h.

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Gotesman, Gilad, Rahamim Guliamov, and Ron Naaman. "Horizontal versus vertical charge and energy transfer in hybrid assemblies of semiconductor nanoparticles." Beilstein Journal of Nanotechnology 3 (September 6, 2012): 629–36. http://dx.doi.org/10.3762/bjnano.3.72.

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We studied the photoluminescence and time-resolved photoluminescence from self-assembled bilayers of donor and acceptor nanoparticles (NPs) adsorbed on a quartz substrate through organic linkers. Charge and energy transfer processes within the assemblies were investigated as a function of the length of the dithiolated linker (DT) between the donors and acceptors. We found an unusual linker-length-dependency in the emission of the donors. This dependency may be explained by charge and energy transfer processes in the vertical direction (from the donors to the acceptors) that depend strongly on charge transfer processes occurring in the horizontal plane (within the monolayer of the acceptor), namely, parallel to the substrate.

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Yao, Jiadong, Wenxuan Guo, Yali Liu, Xinyue Niu, Mengge Li, Xiaoxiang Wu, Ying Yu, Tianjian Ou, Jian Sha, and Yewu Wang. "Gate induced charge transfer and hysteresis enlargement in MoS2/GeSe2 vertical heterostructures." Journal of Materials Chemistry C 9, no. 26 (2021): 8213–19. http://dx.doi.org/10.1039/d1tc01824h.

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We explored the hysteresis enlargement in the vertical MoS₂/GeSe₂ van der Waals heterojunction, and it was attributed to the gate induced charge transfer process between the MoS₂ and GeSe₂ layers.

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Kazemi, Alireza, Sam Vaziri, Jorge Daniel Aguirre Morales, Sébastien Frégonèse, Francesca Cavallo, Marziyeh Zamiri, Noel Dawson, et al. "Retraction of “Vertical Charge Transfer and Lateral Transport in Graphene/Germanium Heterostructures”." ACS Applied Materials & Interfaces 13, no. 6 (February 5, 2021): 7823. http://dx.doi.org/10.1021/acsami.1c01897.

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Roy, Francois, Andrej Suler, Thomas Dalleau, Romain Duru, Daniel Benoit, Jihane Arnaud, Yvon Cazaux, et al. "Fully Depleted, Trench-Pinned Photo Gate for CMOS Image Sensor Applications." Sensors 20, no. 3 (January 28, 2020): 727. http://dx.doi.org/10.3390/s20030727.

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Tackling issues of implantation-caused defects and contamination, this paper presents a new complementary metal–oxide–semiconductor (CMOS) image sensor (CIS) pixel design concept based on a native epitaxial layer for photon detection, charge storage, and charge transfer to the sensing node. To prove this concept, a backside illumination (BSI), p-type, 2-µm-pitch pixel was designed. It integrates a vertical pinned photo gate (PPG), a buried vertical transfer gate (TG), sidewall capacitive deep trench isolation (CDTI), and backside oxide–nitride–oxide (ONO) stack. The designed pixel was fabricated with variations of key parameters for optimization. Testing results showed the following achievements: 13,000 h+ full-well capacity with no lag for charge transfer, 80% quantum efficiency (QE) at 550-nm wavelength, 5 h+/s dark current at 60 °C, 2 h+ temporal noise floor, and 75 dB dynamic range. In comparison with conventional pixel design, the proposed concept could improve CIS performance.

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Seo, Dong-Bum, Tran Trung, Sung-Su Bae, and Eui-Tae Kim. "Improved Photoelectrochemical Performance of MoS2 through Morphology-Controlled Chemical Vapor Deposition Growth on Graphene." Nanomaterials 11, no. 6 (June 17, 2021): 1585. http://dx.doi.org/10.3390/nano11061585.

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The morphology of MoS2 nanostructures was manipulated from thin films to vertically aligned few-layer nanosheets on graphene, in a controllable and practical manner, using metalorganic chemical vapor deposition. The effects of graphene layer and MoS2 morphology on photoelectrochemical (PEC) performance were systematically studied on the basis of electronic structure and transitions, carrier dynamic behavior, and PEC measurements. The heterojunction quality of the graphene/vertical few-layer MoS2 nanosheets was ensured by low-temperature growth at 250−300 °C, resulting in significantly improved charge transfer properties. As a result, the PEC photocurrent density and photoconversion efficiency of the few-layer MoS2 nanosheets significantly increased upon the insertion of a graphene layer. Among the graphene/MoS2 samples, the few-layer MoS2 nanosheet samples exhibited shorter carrier lifetimes and smaller charge transfer resistances than the thin film samples, suggesting that vertically aligned nanosheets provide highly conductive edges as an efficient pathway for photo-generated carriers and have better electronic contact with graphene. In addition, the height of vertical MoS2 nanosheets on graphene should be controlled within the carrier diffusion length (~200 nm) to achieve the optimal PEC performance. These results can be utilized effectively to exploit the full potential of two-dimensional MoS2 for various PEC applications.

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Sahoo, Gopinath, S. R. Polaki, P. Anees, Subrata Ghosh, Sandip Dhara, and M. Kamruddin. "Insights into the electrochemical capacitor performance of transition metal–vertical graphene nanosheet hybrid electrodes." Physical Chemistry Chemical Physics 21, no. 45 (2019): 25196–205. http://dx.doi.org/10.1039/c9cp05656d.

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The enhanced electrochemical capacitance of the transition metal-vertical graphene nanosheet hybrid electrodes are correlated with the increase in charge transfer supported ab initio DFT calculations and increase in electrical conductivity.

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Jeong, Junseok, Kyung-Ah Min, Dong Hoon Shin, Woo Seok Yang, Jinkyoung Yoo, Sang Wook Lee, Suklyun Hong, and Young Joon Hong. "Remote homoepitaxy of ZnO microrods across graphene layers." Nanoscale 10, no. 48 (2018): 22970–80. http://dx.doi.org/10.1039/c8nr08084d.

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Vertical and horizontal ZnO microrods are grown on a- and c-plane ZnO across graphene interlayer, owing to charge transfer through graphene, and the remote homoepitaxial microrods were exfoliated for substrate regeneration.

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11

Zhang, Ying, Kai-Li Zhang, Jun Liu, Jun-Hao Wang, Yao-Qin Feng, Peng-Jun Deng, Xinxin Tian, Gaoyi Han, and Dan Li. "Enhanced emission under proton stimuli based on a phenanthroimidazole derivative by switching the excited state type from the CT to the LE state." Journal of Materials Chemistry C 9, no. 32 (2021): 10226–31. http://dx.doi.org/10.1039/d1tc01928g.

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12

Han, Tao, Hongxia Liu, Shulong Wang, Shupeng Chen, and Kun Yang. "The Large-Scale Preparation and Optical Properties of MoS2/WS2 Vertical Hetero-Junction." Molecules 25, no. 8 (April 17, 2020): 1857. http://dx.doi.org/10.3390/molecules25081857.

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A variety of hetero-junctions can be constructed to form the basic structural units in the different optoelectronic devices, such as the photo-detectors, solar cells, sensors and light-emitting diodes. In our research, the large-area high-quality MoS2/WS2 vertical hetero-junction are prepared by the two-step atmospheric pressure chemical vapor deposition (APCVD) methods and the dry transfer method, and the corresponding optimal reaction conditions of MoS2/WS2 vertical hetero-junction are obtained. The morphology, composition and optical properties of MoS2/WS2 vertical hetero-junction are systematically characterized by the optical microscopy, Raman spectroscopy, photoluminescence spectroscopy, atomic force microscopy and the field emission scanning electron microscopy. Compared to the mechanical transfer method, the MoS2/WS2 vertical hetero-junction sample obtained by the APCVD and dry transfer methods have lower impurity content, cleaner interfaces and tighter interlayer coupling. Besides, the strong interlayer coupling and effective interlayer charge transfer of MoS2/WS2 vertical hetero-junction are also further studied. The photoluminescence intensity of MoS2/WS2 vertical hetero-junction is significantly reduced compared to the single MoS2 or WS2 material. In general, this research can help to achieve the large-scale preparation of various Van der Waals hetero-junctions, which can lay the foundation for the new application of optoelectronic devices.

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13

Rauwolf, Cordula, Achim Mehlhorn, and Jürgen Fabian. "Binding Energies of Organic Charge-Transfer Complexes Calculated by First-Principles Methods." Collection of Czechoslovak Chemical Communications 63, no. 8 (1998): 1223–44. http://dx.doi.org/10.1135/cccc19981223.

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Weak interactions between organic donor and acceptor molecules resulting in cofacially-stacked aggregates ("CT complexes") were studied by second-order many-body perturbation theory (MP2) and by gradient-corrected hybrid Hartree-Fock/density functional theory (B3LYP exchange-correlation functional). The complexes consist of tetrathiafulvalene (TTF) and related compounds and tetracyanoethylene (TCNE). Density functional theory (DFT) and MP2 molecular equilibrium geometries of the component structures are calculated by means of 6-31G*, 6-31G*(0.25), 6-31++G**, 6-31++G(3df,2p) and 6-311G** basis sets. Reliable molecular geometries are obtained for the donor and acceptor compounds considered. The geometries of the compounds were kept frozen in optimizing aggregate structures with respect to the intermolecular distance. The basis set superposition error (BSSE) was considered (counterpoise correction). According to the DFT and MP2 calculations laterally-displaced stacks are more stable than vertical stacks. The charge transfer from the donor to the acceptor is small in the ground state of the isolated complexes. The cp-corrected binding energies of TTF/TCNE amount to -1.7 and -6.3 kcal/mol at the DFT(B3LYP) and MP2(frozen) level of theory, respectively (6-31G* basis set). Larger binding energies were obtained by Hobza's 6-31G*(0.25) basis set. The larger MP2 binding energies suggest that the dispersion energy is underestimated or not considered by the B3LYP functional. The energy increases when S in TTF/TCNE is replaced by O or NH but decreases with substitution by Se. The charge-transferred complexes in the triplet state are favored in the vertical arrangement. Self-consistent-reaction-field (SCRF) calculations predicted a gain in binding energy with solvation for the ground-state complex. The ground-state charge transfer between the components is increased up to 0.8 e in polar solvents.

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14

Li, Jieyuan, Wen Cui, Yanjuan Sun, Yinghao Chu, Wanglai Cen, and Fan Dong. "Directional electron delivery via a vertical channel between g-C3N4 layers promotes photocatalytic efficiency." Journal of Materials Chemistry A 5, no. 19 (2017): 9358–64. http://dx.doi.org/10.1039/c7ta02183f.

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Mediated by intercalated alkalis between the layers of g-C₃N₄, a directional electron delivery channel vertical to the planes has been established, which enhances charge separation and transfer, thus significantly improving the g-C₃N₄ photocatalytic efficiency.

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15

Ziaei, Vafa, and Thomas Bredow. "GW-BSE approach on S1 vertical transition energy of large charge transfer compounds: A performance assessment." Journal of Chemical Physics 145, no. 17 (November 7, 2016): 174305. http://dx.doi.org/10.1063/1.4966920.

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16

Boynazarov, Turgun, Junsu Lee, and Gunn Kim. "Magnetic moment changed by interlayer charge transfer in vertical graphene/C-doped hexagonal boron nitride heterostructure." Chemical Physics Letters 692 (January 2018): 81–87. http://dx.doi.org/10.1016/j.cplett.2017.12.007.

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17

Zheng, Weihao, Biyuan Zheng, Changlin Yan, Ying Liu, Xingxia Sun, Zhaoyang Qi, Tiefeng Yang, et al. "Direct Vapor Growth of 2D Vertical Heterostructures with Tunable Band Alignments and Interfacial Charge Transfer Behaviors." Advanced Science 6, no. 7 (February 14, 2019): 1802204. http://dx.doi.org/10.1002/advs.201802204.

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18

Stampa, C. S., and A. O. Nieckele. "NUMERICAL ANALYSIS OF INDIRECT ICE STORAGE SYSTEMS PERFORMANCE." Revista de Engenharia Térmica 5, no. 1 (July 31, 2006): 84. http://dx.doi.org/10.5380/reterm.v5i1.61677.

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A numerical investigation regarding the charging process behavior occurring in a typical indirect ice storage tank is presented. It consists of analyzing the heat transfer and removal of energy, applicable to storage systems, which are chiller-based. In this sense the secondary coolant circulates through a heat exchanger that is submerged in a tank of water and it is used to freeze (charge) the phase-change material (water), which never leaves the storage tank. The thermal exchange process is investigated considering the storage tank in two different positions. In the first one the storage tank is in the vertical position, while for the second, it is horizontally positioned. The storage tank is represented by a channel formed by parallel flat plates, one of which is the heat exchanger. Our task is to provide helpful qualitative results for the heat transfer performance of ice storage tanks. The results are analysed through streamlines and isotherms, for specific instants of time. Further, the heat transfer effectiveness, average heat flux and solid formed at one of the two plates of the channel, are compared for the vertical and horizontal positions of the channel.

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19

Heimgartner, P., and H. Bohni. "Mechanistic Aspects of Pit Growth on Nickel in Diluted Chloride Solutions." Corrosion 41, no. 12 (December 1, 1985): 715–19. http://dx.doi.org/10.5006/1.3583008.

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Abstract Pit current densities (CDs) in small pits have been found to be potential dependent, indicating an ohmic or mixed ohmic-charge transfer controlled dissolution mechanism. In a later stage of pit growth, a diffusion-controlled dissolution has often been reported. The potential-dependent mechanism is not always restricted to only the beginning of pit development, as has been shown in galvanostatic tests with rather low CDs. In this paper, the mechanism change from ohmic-charge transfer to diffusion-controlled pit growth was also studied in potentiostatic experiments by means of potential pulses added to the applied potential. The current response to fast potential changes differs for the two mechanisms. The influence of a number of parameters [such as potential, position of the specimen (horizontal or vertical), agitation of the bulk electrolyte, and pit diameter] on the transition time for mechanism change could be investigated using this pulse technique. Results also show that the rate law for pit growth can be very similar for the two types of mechanisms and different pit geometry (artificial pits of the wire type or “naturally” growing pits).

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Chaudhuri, Tandrima, Sunita Santra, Sourav Jana, and Alakananda Hajra. "Determination of vertical ionization potential of nitroso-benzoimidazothiazole using charge transfer interaction with a series of acceptors." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 204 (November 2018): 403–8. http://dx.doi.org/10.1016/j.saa.2018.06.083.

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Gorelsky, S. I., V. Yu Kotov, and A. B. P. Lever. "Vertical Ionization Energies and Electron Affinities of Ions in Solution from Outer-Sphere Charge Transfer Transition Energies." Inorganic Chemistry 37, no. 18 (September 1998): 4584–88. http://dx.doi.org/10.1021/ic980217i.

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Bhattacharya, Sumanta, Anubha Sharma, Sandip K. Nayak, and Asok K. Mukherjee. "Vertical ionisation potentials of a number of crown ethers from charge transfer bands of their EDA complexes." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 58, no. 13 (November 2002): 2841–48. http://dx.doi.org/10.1016/s1386-1425(02)00079-3.

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23

Luo, Qing, Miaomiao Li, Xiangzhe Zhang, Hongxiang Shi, Guang Wang, Sen Zhang, Chuyun Deng, et al. "Lateral and Vertical p–n Homojunctions Formed in Few-Layer MoTe2 with In Surface Charge-Transfer Doping." ACS Applied Electronic Materials 3, no. 8 (July 29, 2021): 3428–35. http://dx.doi.org/10.1021/acsaelm.1c00407.

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24

Zhang, Kehao, Bhakti Jariwala, Jun Li, Natalie C. Briggs, Baoming Wang, Dmitry Ruzmetov, Robert A. Burke, et al. "Large scale 2D/3D hybrids based on gallium nitride and transition metal dichalcogenides." Nanoscale 10, no. 1 (2018): 336–41. http://dx.doi.org/10.1039/c7nr07586c.

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Large area 2D MoS₂ and WSe₂ are integrated on 3D GaN by metal organic chemical vapor deposition (MOCVD). The thickness-dependent vertical tunneling and interlayer charge transfer is carefully studied. This work shows that few layer WSe₂ film is the appropriate choice towards device application of synthetic 2D/3D heterostructures.

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JEON, SANG YOUN, KYUNG AH PARK, IN-SU BAIK, SEOK JIN JEONG, SEOK HO JEONG, KAY HYEOK AN, SEUNG HEE LEE, and YOUNG HEE LEE. "DYNAMIC RESPONSE OF CARBON NANOTUBES DISPERSED IN NEMATIC LIQUID CRYSTAL." Nano 02, no. 01 (February 2007): 41–49. http://dx.doi.org/10.1142/s1793292007000350.

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The alignment and dynamic response of carbon nanotubes (CNTs) in nematic liquid crystal (NLC) medium induced by strong electric field have been observed through polarizing optical microscope. Density-functional calculations suggest that LC molecule anchors helically to the CNT wall to enhance π-stacking with a binding energy of nearly -2.0 eV due to a considerable amount of charge transfer from LC molecule to CNT, resulting in the formation of excess charges and permanent dipole moment in CNTs. Under strong electric field, the motion of CNTs distorted the director of adjacent LC molecules. Our detailed analysis of dynamics revealed that the four-lobe textures in vertical cell and two vertical stripes in in-plane switching cell were strongly correlated, i.e., the side view of textures by the vertical motion of CNTs in vertical cell was similar to the textures in in-plane switching cell. Interestingly, the magnitude of textures in microscope was strongly dependent on the size of CNTs and the applied field strength. The statistical size distribution of textures similar to that of CNTs provided information for the degree of dispersion of CNTs.

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Bejan, Andrei–Stelian, Abdelouhab Labihi, Cristiana Verona Croitoru, Tiberiu Catalina, Hassan Chehouani, and Brahim Benhamou. "Experimental investigation of the charge/discharge process for an organic PCM macroencapsulated in an aluminium rectangular cavity." E3S Web of Conferences 32 (2018): 01004. http://dx.doi.org/10.1051/e3sconf/20183201004.

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Buildings sector has one of the highest potential regarding the reduction of greenhouse gases emissions, as being responsible for more than 40% of energy consumption worldwide. This is why, in order to achieve indoor thermal comfort, it is mandatory to use energy-efficient systems. Materials acting as thermal energy storage (TES) represents one of the most effective strategy that can be implemented and nowadays, many studies are focusing their attention on latent heat storage, respectively on phase changing materials (PCM) which can embed a large embed a high quantity of energy, unlike classic materials acting as thermal mass. This purpose of this paper is to experimentally investigate the charge and discharge processes for an organic PCM (RT35 paraffin) macroencapsulated in an aluminium rectangular cavity which was placed first in a horizontal position and after in a vertical position. After several experimental campaigns conducted we determined that the vertical position enhance the heat transfer because of the natural convection which occurs inside the cavity. Therefore, the charging time is lower in case of the vertical cavity and the temperature measured inside and on the surface is higher.

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Ali, Amjad, Muhammad Imran Rafiq, Baojing Zhou, and Weihua Tang. "Evaluating the nature of the vertical excited states of fused-ring electron acceptors using TD-DFT and density-based charge transfer." Physical Chemistry Chemical Physics 23, no. 28 (2021): 15282–91. http://dx.doi.org/10.1039/d1cp01917a.

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Fused-ring electron acceptors (FREAs) are efficient acceptors for organic solar cells. The DFT, its time-dependent version (TD-DFT) and an intra-molecular charge transfer index are employed to evaluate the nature of the excited states of FREAs.

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28

Asshoff, P. U., J. L. Sambricio, A. P. Rooney, S. Slizovskiy, A. Mishchenko, A. M. Rakowski, E. W. Hill, et al. "Magnetoresistance of vertical Co-graphene-NiFe junctions controlled by charge transfer and proximity-induced spin splitting in graphene." 2D Materials 4, no. 3 (June 22, 2017): 031004. http://dx.doi.org/10.1088/2053-1583/aa7452.

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Huang, Jing, Junwei Mei, Jianxin Han, Hui Liang, Wei Wang, Bohua Dong, and Lixin Cao. "Vertical 1T/2H-WS2 nanoflakes grown on 2D-C3N4: Multiple charge transfer channels designed for enhanced photocatalytic activity." Journal of Colloid and Interface Science 556 (November 2019): 224–31. http://dx.doi.org/10.1016/j.jcis.2019.08.043.

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30

Je, Minyeong, Eun Seob Sim, Jungwook Woo, Heechae Choi, and Yong-Chae Chung. "Manipulatable Interface Electric Field and Charge Transfer in a 2D/2D Heterojunction Photocatalyst via Oxygen Intercalation." Catalysts 10, no. 5 (April 25, 2020): 469. http://dx.doi.org/10.3390/catal10050469.

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Charge separation is the most important factor in determining the photocatalytic activity of a 2D/2D heterostructure. Despite the exclusive advantages of 2D/2D heterostructure semiconductor systems such as large surface/volume ratios, their use in photocatalysis is limited due to the low efficiency of charge separation and high recombination rates. As a remedy for the weak interlayer binding and low carrier transport efficiency in 2D/2D heterojunctioned semiconductors, we suggested an impurity intercalation method for the 2D/2D interface. PtS2/C3N4, as a prototype heterojunction material, was employed to investigate the effect of anion intercalation on the charge separation efficiency in a 2D/2D system using density functional theory. With oxygen intercalation at the PtS2/C3N4 interface, a reversed and stronger localized dipole moment and a built-in electric field were induced in the vertical direction of the PtS2/C3N4 interface. This theoretical work suggests that the anion intercalation method can be a way to control built-in electric fields and charge separation in designs of 2D/2D heterostructures that have high photocatalytic activity.

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Dhiman, Shobhna, Ranjan Kumar, and Keya Dharamvir. "Small Al and Ga clusters trapped inside the Bucky-ball (C60) — A DFT study." International Journal of Modern Physics B 31, no. 12 (May 10, 2017): 1750092. http://dx.doi.org/10.1142/s0217979217500928.

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In the present paper, we have done a systematic study of structural and electronic properties of endohedrally doped C[Formula: see text] with Al and Ga atoms using density functional theory (DFT) with the help of Spanish initiative for electronic simulation with thousands of atoms (SIESTA) package in the generalized gradient approximation (GGA). The parameters calculated are binding energy/dopant atom, vertical ionization potential (VIP), vertical electron affinity (VEA), HOMO–LUMO gap and charge transfer. The stabilized ground state structures of Al[Formula: see text]@C[Formula: see text] ([Formula: see text]–10) and Ga[Formula: see text]@C[Formula: see text] ([Formula: see text]–10) show that a maximum of nine Al or Ga atoms can be encapsulated in C[Formula: see text] without distorting the cage significantly. Mulliken charge analysis shows an electron transfer from the metal dopant to the cage surface, except for Al[Formula: see text] ([Formula: see text]–10). The endohedral metal clusters adopt a more compact shape when inside C[Formula: see text], compared to its free-state configuration and its symmetry. The study of HOMO–LUMO gap reveals that the gap decreases with the increase in number of dopant atoms inside C[Formula: see text].

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32

Maeno, N., R. Naruse, K. Nishimura, I. Takei, T. Ebinuma, S. Kobayabhi, H. Nlshlmura, Y. Kaneda, and T. Ishida. "Wind-Tunnel Experiments on Blowing Snow." Annals of Glaciology 6 (1985): 63–67. http://dx.doi.org/10.3189/1985aog6-1-63-67.

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Blowing snow was produced artificially in a cold wind-tunnel, and various measurements were conducted including particle diameters, concentrations, saltation lengths heat transport and electric charge. The mean diameter of blowing snow particles decreased only slightly with increasing height; in the saltation layer, standard deviation was large and velocities were scattered in a wide range, suggesting the complex dynamic process on taking-off. The mean saltation length ranged from a few cm to 40 cm increasing with wind velocity.When wind blew without snow drifting, the static air pressure on the snow surface was smaller at higher levels, the vertical pressure gradient being negative. The pressure gradient became positive when blowing snow was initiated eg +9.6 Pa/m at 11.2 m/s and -8.3 °C. The magnitude of à downward force acting on a saltating snow partice caused by the pressure gradient was not large enough to explain the downward acceleration found from photographic analyses of particle trajectories.Blowing snow particles were charged negatively the magnitude of charge increased with lowering temperature. Increase in vertical heat transfer was found in blowing snow by measuring the temperature of the air at various levels; the increase is reflected on that in the apparent turbulent diffusion coefficient.

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Maeno, N., R. Naruse, K. Nishimura, I. Takei, T. Ebinuma, S. Kobayabhi, H. Nlshlmura, Y. Kaneda, and T. Ishida. "Wind-Tunnel Experiments on Blowing Snow." Annals of Glaciology 6 (1985): 63–67. http://dx.doi.org/10.1017/s0260305500010004.

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Blowing snow was produced artificially in a cold wind-tunnel, and various measurements were conducted including particle diameters, concentrations, saltation lengths heat transport and electric charge. The mean diameter of blowing snow particles decreased only slightly with increasing height; in the saltation layer, standard deviation was large and velocities were scattered in a wide range, suggesting the complex dynamic process on taking-off. The mean saltation length ranged from a few cm to 40 cm increasing with wind velocity.When wind blew without snow drifting, the static air pressure on the snow surface was smaller at higher levels, the vertical pressure gradient being negative. The pressure gradient became positive when blowing snow was initiated eg +9.6 Pa/m at 11.2 m/s and -8.3 °C. The magnitude of à downward force acting on a saltating snow partice caused by the pressure gradient was not large enough to explain the downward acceleration found from photographic analyses of particle trajectories.Blowing snow particles were charged negatively the magnitude of charge increased with lowering temperature. Increase in vertical heat transfer was found in blowing snow by measuring the temperature of the air at various levels; the increase is reflected on that in the apparent turbulent diffusion coefficient.

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34

Jha, Basant Kumar, and Michael O. Oni. "Fully developed mixed convection flow in a vertical channel with electrokinetic effects." Multidiscipline Modeling in Materials and Structures 14, no. 5 (December 6, 2018): 1031–41. http://dx.doi.org/10.1108/mmms-10-2017-0123.

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PurposeThe purpose of this paper is to investigate electrokinetic and mixed convection (pressure gradient and buoyancy) effects on reverse flow formation at the channel walls.Design/methodology/approachThe electrical potential distribution was modelled using the Poisson–Boltzmann equation while the governing momentum and energy equations are modelled from the Navier–Stokes equations and solved exactly.FindingsIt is found that flow reversal at the walls is enhanced by electrokinetic parameter whereas increasing degree of asymmetric parameter up to symmetric heating eliminates reverse flow formation at the walls no matter the electric charge distribution.Originality/valueThe results of this paper indicate that degree of asymmetric heating, mixed convection parameter and electrokinetic parameter regulate fluid velocity, rate of heat transfer, skin friction and reverse flow formation at the walls.

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35

Pan, Yue, Xuewu Fan, Hui Zhao, Yulei Qiu, Wei Gao, and Jian Zhang. "Fast Dark Signal Measurements of SVOM VT CCDs Using the Vertical Gradient of Dark Field Images." Photonics 8, no. 4 (April 20, 2021): 132. http://dx.doi.org/10.3390/photonics8040132.

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This paper describes a fast technique for estimating the dark signals of the charge coupled devices (CCDs) of the visible telescope (VT) onboard the space multi-band variable object monitor (SVOM). It is based on the vertical gradient in the dark field images of the frame transfer CCDs. During the process of frame clear, exposure, frame transfer and readout, the characteristic of dark signal accumulation is analyzed firstly. Next, the linear fitting method is used to fit the signal level of the dark field image in the vertical direction, and the slope of the fitting line represents the dark signal factor. This technique only needs one dark field image and can be used for simple and efficient dark signal measurements of frame transfer CCDs. Besides, an experiment of detecting dark signals as a function of temperature based on the fast technique has been carried out. Making use of the Shockley-Hall-Read theory, two curve fitting formulas are adopted to the experimental results for VT Advanced Inverted Mode Operation (AIMO) CCD and VT Non-Inverted Mode Operation (NIMO) CCD respectively. The experimental results and the formulas are used to determine the optimal on-orbit cooling temperature of VT CCDs.

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Heidari, Sakineh, Hamzeh Alaibakhsh, and Mohammad Azim Karami. "3D device‐level simulation of charge separation from sidewall in vertical transfer gate pinned photodiode pixels for noise mitigation." IET Circuits, Devices & Systems 14, no. 5 (June 2020): 619–22. http://dx.doi.org/10.1049/iet-cds.2019.0501.

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Wei, Qiang, Jiyu Wang, Meiyu Zhao, Meixia Zhang, Yuzhi Song, and Peng Song. "A theoretical investigation on excited-state single or double proton transfer process for aloesaponarin I." Canadian Journal of Chemistry 96, no. 1 (January 2018): 83–88. http://dx.doi.org/10.1139/cjc-2017-0533.

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The excited-state proton transfer (ESPT) dynamical behavior of aloesaponarin I (ASI) was studied using density functional theory (DFT) and time-dependent DFT (TDDFT) methods. Our calculated vertical excitation energies based on TDDFT reproduced the experimental absorption and fluorescence spectra well [Nagaoka et al. J. Phys. Chem. B, 117, 4347 (2013)]. Two intramolecular hydrogen bonds were confirmed to be strengthened in the S1 state, which makes ESPT possible. Herein, the ESPT process is more likely to happen, along with one hydrogen bond (O1–H2⋯O3). Qualitative analyses about charge distribution further demonstrate that the ESPT process could occur because of the intramolecular charge transfer. Our constructed potential energy surfaces of both S0 and S1 states show that a single proton transfer reactive is more reasonable along with the intramolecular hydrogen bond (O1–H2⋯O3) rather than O4–H5⋯O6 in the S1 stated potential energy surface. Then, ASI-SPT* decays to the ground state with a 640 nm fluorescence; subsequently, the ASI-SPT form shows that reverse ground state single-proton transfer back to the ASI structure occurs. Particularly, dependent on relatively accurate potential energy barriers among these excited-state stable structures, we confirmed the excited-state single proton transfer process rather than using the controversial nodal plane model.

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Tian, Ye, Hong Wang, Qiyuan Deng, Xun Zhu, Rong Chen, Yudong Ding, and Qiang Liao. "Dynamic behaviors and charge characteristics of droplet in a vertical electric field before bouncing." Experimental Thermal and Fluid Science 119 (November 2020): 110213. http://dx.doi.org/10.1016/j.expthermflusci.2020.110213.

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Cheedarala, Ravi Kumar, Le Chau Duy, and Kyoung Kwan Ahn. "Double characteristic BNO-SPI-TENGs for robust contact electrification by vertical contact separation mode through ion and electron charge transfer." Nano Energy 44 (February 2018): 430–37. http://dx.doi.org/10.1016/j.nanoen.2017.12.019.

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Bui, Viet Q., Hung M. Le, Yoshiyuki Kawazoe, and Yongho Kim. "Adjusting band gap and charge transfer of organometallic complex adsorbed on MoS2monolayer using vertical electric-field: a first-principles investigation." Journal of Physics: Condensed Matter 29, no. 1 (November 10, 2016): 015003. http://dx.doi.org/10.1088/0953-8984/29/1/015003.

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Gao, Nan, Xiaochen Lin, Jinglin Liu, Yuanzuo Li, and Yanhui Yang. "Photoactuated Properties of Acetylene-Congeners Non-Metallic Dyes and Molecular Design for Solar Cells." Materials 11, no. 10 (October 18, 2018): 2027. http://dx.doi.org/10.3390/ma11102027.

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This paper theoretically simulated (using DFT and TD-DFT in N,N-dimethylformamide (DMF) solvent) the photodynamic properties of three non-metallic dye molecules with D-π-A1-π-A2 structure. The total photoelectric conversion efficiency (PCE) could be evaluated by the following parameters: the geometric structures, the electronic structures, and the absorption spectra, the analyses of charge difference density (CDD) and natural bond orbitals (NBO), the analyses of ionization potential (IP) and electron affinity (EA) from electronic contribution capacity, the reorganization energies (λh, λe, and λtotal), and the chemical reaction parameter (h, ω, ω-, and ω+) for intramolecular charge transfer (ICT) processing, the excited lifetime (τ) and the vertical dipole moment (μnormol). The ∆Ginject, the ∆Gdyeregen, the light harvesting efficiencies (LHE) and the excited lifetime (τ) were used to explain experimental JSC. The experimental trend of VOC was explained by the calculation of ∆ECB and μnormol. Moreover, the 15 dyes were designed by adding the electron-donor groups (–OH, –NH2, and –OCH3) and the electron-acceptor groups (–CF3, –F, and −CN) to the LS-387 molecular skeleton, which improved electronic contribution, intramolecular charge transfer (ICT), and optoelectronic performance.

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Hasanein, Ahmed A., Yasser R. Elmarassi, and Ahmed M. Ramadan. "TD-DFT study on some triphenylamine-based organic dyes as photosensitizers in DSSCs." Journal of Theoretical and Computational Chemistry 13, no. 08 (December 2014): 1450064. http://dx.doi.org/10.1142/s0219633614500643.

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Geometrical and molecular electronic structure calculations on a series of metal free organic dyes based on triphenylamine (TPA) moiety have been performed using the TD-DFT methods. The B3LYP/6-31G, B3LYP/6-31G(d,p), M06-HF/6-31G(d,p) and WB97XD/6-31G(d,p) levels of theory have been utilized to predict the relationships between chemical structure and theoretically calculated molecular electronic properties of the studied dyes which may help in optimizing the properties of TPA-based photosensitizers in DSSCs. The solvation process of these dyes has been taken into account by means of the polarizable continuum model. The light harvesting efficiency, the free energy change for the electron injection process to the surface of TiO 2 nanocrystalline semiconductor and the open circuit potential are calculated using all of these methods in different media. Significant charge transfer character of the HOMO → LUMO electronic transition which dominates the So → S1 vertical excitation in these systems facilitates the electron transfer process to the surface of TiO 2. The results of the present computations are reported and discussed.

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Farid, Mohammed M., and Atsushi Kanzawa. "Thermal Performance of a Heat Storage Module Using PCM’s With Different Melting Temperatures: Mathematical Modeling." Journal of Solar Energy Engineering 111, no. 2 (May 1, 1989): 152–57. http://dx.doi.org/10.1115/1.3268301.

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In the present study, the performance of a heat storage unit consisting of number of vertical cylindrical capsules filled with phase change materials, with air flowing across them for heat exchange has been analyzed. Earlier theoretical models did not consider temperature distribution in the radial direction within the capsules, an assumption that limits their applications for small diameter capsules. The mathematical model developed in this work is based on solving the heat conduction equation in both melt and solid phases in cylindrical coordinates, taking into account the radial temperature distribution in both phases. Heat flux was then evaluated at the surface of the first row of the capsules to determine the temperature of the air leaving that row by a simple heat balance. It was found that such computation may be carried out for every few rows rather than for a single row to minimize computer time. The simulation study showed a significant improvement in the rate of heat transfer during heat charge and discharge when phase change materials with different melting temperatures were used. Air must flow in the direction of decreasing melting temperature during heat charge, while it must be reversed during heat discharge.

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Ji, Min, Xinlu Cheng, and Weidong Wu. "Al-doped graphene as an effective adsorber for some toxic derivatives of aromatic hydrocarbons." Journal of Theoretical and Computational Chemistry 16, no. 01 (February 2017): 1750004. http://dx.doi.org/10.1142/s0219633617500043.

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The density functional theory (DFT) was used to investigate some toxic derivatives of aromatic hydrocarbons adsorption on perfect graphene (pG) and graphene-doped with B/Al/Ga (BG/AlG/GaG). And the parallel and vertical adsorptions were considered for the position relation between the adsorbent and adsorbate. The adsorption energy, adsorption distance, charge transfer and density of states (DOS) were discussed in optimized structures. The greater adsorption energy, shorter adsorption distance and more charge transfer were found in AlG by studying the four kinds of molecules (phenol/m-cresol/PCP/p-NP) adsorption on pG/BG/AlG/GaG. Then, 10 derivatives adsorption on AlG were reported, and the adsorption energy increased in the order of pentachlorophenol [Formula: see text] 2,4,6-trichlorophenol [Formula: see text] 2,4-dichlorophenol [Formula: see text] p-cresol [Formula: see text] m-cresol [Formula: see text] phenol [Formula: see text] o-chlorophenol [Formula: see text] o-cresol [Formula: see text] 2,4,6-trintrotoluene [Formula: see text] para-nitrophenol. The interaction between these derivatives and the substrate was chemisorption for AlG and physisorption for pG. The oxygen atom in nitro group was more closer to the substrate than in hydroxyl group about optimized structures.

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Gritsenko, Oleg, and Evert Jan Baerends. "The analog of Koopmans’ theorem for virtual Kohn–Sham orbital energies." Canadian Journal of Chemistry 87, no. 10 (October 2009): 1383–91. http://dx.doi.org/10.1139/v09-088.

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An analog of Koopmans’ theorem is formulated for the energies, εa, of virtual Kohn–Sham (KS) molecular orbitals (MOs) from the requirement that the KS theory provides, in principle, not only the exact electron density, but also its exact response. The starting point is the Kohn–Sham analog of Koopmans’ theorem, relating the vertical ionization energies, Ii, to the energies, εi, of the occupied MOs ( Chong, D.P.; Gritsenko, O.V.; Baerends, E.J. J. Chem. Phys. 2002, 116, 1760 ). Combining this with the coupled-perturbed equations of time-dependent density functional theory (TDDFT), exact relations between the energies, εa, of virtual KS MOs and the excitation energies, ωia, and vertical ionization energies (VIPs), Ii, are obtained. In the small matrix approximation for the coupling matrix K of TDDFT, two limiting cases of these relations are considered. In the limit of a negligible matrix element, Kia,ia, the energy, εa, can be interpreted as (minus) the energy of ionization from the ?i → ?a excited state, εa ≈ –Ia, where –Ia is defined from the relation Ii = ωia + Ia. This relation breaks down in special cases, such as charge-transfer transitions and the HOMO–LUMO (highest occupied molecular orbital – lowest unoccupied molecular orbital) transition of a dissociating electron-pair bond (also of charge-transfer character). The present results highlight the important difference between virtual orbital energies in the Kohn–Sham model (εa ≈ –Ia) and in the Hartree–Fock model (εa ≈ –Aa). Kohn–Sham differences εa – εi approximate the excitation energy, ωia, while Hartree–Fock differences [Formula: see text] do not approximate excitation energies but approximate the difference of an ionization energy and an electron affinity, Ii – Aa.

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Pryalkin, Boris S., and Yulia S. Bodagova. "Molecular Complexes of p-Chloranil with Aniline, Phenol and their Derivatives." Key Engineering Materials 670 (October 2015): 89–94. http://dx.doi.org/10.4028/www.scientific.net/kem.670.89.

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Classification of simple supramolecular structures (for example molecular complexes), which has been introduced and described by Mulliken [1], is based on types of molecular orbitals of the components. In the paper [2], disadvantages of such classification are shown, which motivate us to return to the re-examination properties of molecular complexes. By this reason, there is a need to research the molecular complexes of one electron acceptor with a wide range of electron donor molecules. This paper have continued work (Part I [3]) on the chloranil complexes by studying the spectral properties complexes of N- and O-unsubstituting anilines and phenols. The present work aimed at analyzing linear relation the energies of charge-transfer bands of molecular complexes are related to ionization potentials of the donor components. All complexes conform to linear relations like involving both adiabatic and vertical ionization potentials of donor components. Mulliken [1] has been proposed to apply the vertical ionization potentials of donor components only. The development of photoelectron spectroscopy has led to the measurement of adiabatic and vertical ionization energies for thousands of molecules, which allow theirs to the present analysis of spectral properties molecular complexes.

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Matthews, D., and A. Stanley. "The Potential Dependence of the Rate Constant for Charge Transfer at the Semiconductor-Redox Electrolyte Interface." Australian Journal of Chemistry 49, no. 7 (1996): 731. http://dx.doi.org/10.1071/ch9960731.

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The kinetics of charge transfer at the semiconductor- redox electrolyte interface is described in terms of the Gurney- Gerischer -Marcus (GGM) model by using nuclear configuration potential energy diagrams, electronic configuration potential energy diagrams, density of state distributions and rate constant distributions. The model of identical parabolas for the nuclear configuration diagrams is used; this leads to Gaussian oxidant and reductant distribution functions, g(E), where E is the vertical transition (Franck-Condon) energy. The rate constant distribution, k(E), is obtained from the overlap between occupied and unoccupied state distribution functions of the semiconductor and redox electrolyte. Integration of k(E) gives the rate constant which is calculated as a function of the Helmholtz potential, VH, for various values of the reorganization energy, Ereorg. Three types of semiconductor are considered: intrinsic, doped and highly doped. For intrinsic semiconductors the charge transfer rate constant is relatively small and involves both the conduction and valence bands. For symmetric charge transfer (zero energy change, E0.0, for the reaction) both oxidation and reduction occur between the redox electrolyte and both bands of the semiconductor. For unsymmetrical reactions, charge transfer tends to involve only one of the bands; for net reduction, the valence band is involved, whereas for net oxidation the conduction band is involved. For doped semiconductors the rate constant is larger and only one band is involved; for n-type it is the conduction band, and for p-type it is the valence band. For highly doped semiconductors with the Fermi level in either the conduction or valence bands. the rate constant is even larger and only one band is involved. Changes in Helmholtz potential affect k(E) in a similar way to that for metals. However, unlike for metals, the calculated Tafel plots for highly doped n-type semiconductors are shown to exhibit a Marcus inversion region. This is a consequence of the energy gap between conduction and valence bands of the semiconductor. For doped semiconductors, changes in the Helmholtz potential also produce a maximum in the Tafel plot and because of the relatively low currents involved this maximum should be experimentally observable. For intrinsic semiconductors, variation of Helmholtz potential without inclusion of band bending in the semiconductor produces unexpectedly low Tafel slopes which are related to the ratio of the band gap to the reorganization energy, so that the larger the ratio the smaller the Tafel slope. This unexpected result, which amounts to an assumption of band edge unpinning, is shown to accurately account for the experimentally observed Tafel slopes for reduction at n-WSe2 of the dimethylferrocenium ion in acetonitrile.

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Milovanovic, Branislav, Milena Petkovic, and Mihajlo Etinski. "Properties of the excited electronic states of guanine quartet complexes with alkali metal cations." Journal of the Serbian Chemical Society 85, no. 8 (2020): 1021–32. http://dx.doi.org/10.2298/jsc191025140m.

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G-quartets are supra-molecular structures that consist of four guanine molecules connected by eight hydrogen bonds. They are additionally stabilized by metal cations. In this contribution, the excited states of G-quartet and its complexes with lithium, sodium and potassium were studied by employing time-dependent density functional theory. The findings indicate that vertical excitations from the optimized ground state involve transitions from several bases, whereas excitations from the optimized lowest excited state include transitions from one base. The charge-transfer character of these states was analyzed. It was shown that the cations are able to modify positions of the maxima of the fluorescence spectra of the complexes.

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Jiang, Yuanyuan, and Xiaozhang Zhu. "High-Performance Ternary Organic Solar Cells Enabled by Synergizing Fullerene and Non-fullerene Acceptors." Organic Materials 03, no. 02 (March 31, 2021): 254–76. http://dx.doi.org/10.1055/a-1472-3989.

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With the development of the non-fullerene acceptors (NFAs), the use of ternary organic photovoltaic devices based on a fullerene acceptor and a NFA is now widespread, and the merits of both acceptor types can be fully utilized. However, the effective approach of enhancing device performance is adjusting the charge dynamics and the thin-film morphology of the active layer via introducing the second acceptor, which would significantly impact the open-circuit voltage, the short-circuit current, and the fill factor, thus strongly affecting device efficiency. The functions of the second acceptor in a ternary organic solar cell with a fullerene acceptor and a NFA are summarized here. These include a broader absorption spectrum; formation of a cascade energy level or energy transfer; modified thin-film morphology including phase separation, effects on crystallinity, size, and purity of domain; and vertical distribution along with improved charge dynamics like exciton dissociation and charge transport, collection, and recombination. Then, we discuss the hierarchical morphology in ternary solar cells, which may benefit device performance, and the outlook of the ternary device.

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Huang, Jinying, Dongge Ma, and Ivo A. Hümmelgen. "Performance of hybrid p-type vertical transistors with poly(N-vinylcarbazole) as emitter and the transfer mechanism of charge carriers through the base." Semiconductor Science and Technology 28, no. 11 (September 18, 2013): 115001. http://dx.doi.org/10.1088/0268-1242/28/11/115001.

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Journal articles on the topic 'Vertical charge transfer'

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