Search

Your search keyword '"Qiu, Xinkai"' showing total 152 results
Start Over Author "Qiu, Xinkai"
152 results on '"Qiu, Xinkai"'

1. Study on Water-saving Potential and Incentive Systems in Southern Water-lifting Irrigation Districts

Author

Hu Rongxiang, Wang Yu, Xiao Wanchuan, Wang Yujie, and Qiu Xinkai

Subjects
Environmental sciences, GE1-350
Abstract

It is of immense significance for agricultural water-saving work to stimulate the initiative of water users and enhance their water-saving awareness. Focusing on the southern water-lifting irrigation districts, this paper employs various water-saving potential analysis methods(water quota method and Irrigation test method) to calculate the water-saving potential of irrigation districts. The irrigation control indexes of the single-season rice trial in the experimental station adopt conventional irrigation mode. Based on irrigation test results, different water-saving grades are determined, and then, water-saving rewards are granted accordingly. The establishment of water-saving incentive systems shows positive effects on promoting water and energy conservation at pump stations, facilitating the benign operation of agricultural water conservancy projects.

Published
2024
Full Text
View/download PDF

3. Enhancing the Conductivity and Thermoelectric Performance of Semicrystalline Conducting Polymers Through Controlled Tie Chain Incorporation

Author

Zhu, Wenjin, primary, Qiu, Xinkai, additional, Laulainen, Joonatan E. M., additional, Un, Hio‐leng, additional, Ren, Xinglong, additional, Xiao, Mingfei, additional, Freychet, Guillaume, additional, Vacek, Petr, additional, Tjhe, Dion, additional, He, Qiao, additional, Wood, William, additional, Wang, Zichen, additional, Zhang, Youcheng, additional, Qu, Zhengkang, additional, Asatryan, Jesika, additional, Martin, Jaime, additional, Heeney, Martin, additional, McNeill, Christopher R., additional, Midgley, Paul A., additional, Jacobs, Ian E., additional, and Sirringhaus, Henning, additional

Published
2024
Full Text
View/download PDF

7. Solid-State Protein Junctions: Cross-Laboratory Study Shows Preservation of Mechanism at Varying Electronic Coupling

Author

Mukhopadhyay, Sabyasachi, Karuppannan, Senthil Kumar, Guo, Cunlan, Fereiro, Jerry A., Bergren, Adam, Mukundan, Vineetha, Qiu, Xinkai, Castañeda Ocampo, Olga E., Chen, Xiaoping, Chiechi, Ryan C., McCreery, Richard, Pecht, Israel, Sheves, Mordechai, Pasula, Rupali Reddy, Lim, Sierin, Nijhuis, Christian A., Vilan, Ayelet, and Cahen, David

Published
2020
Full Text
View/download PDF

13. N-type organic thermoelectrics: demonstration of ZT > 0.3

Author

Liu, Jian, van der Zee, Bas, Alessandri, Riccardo, Sami, Selim, Dong, Jingjin, Nugraha, Mohamad I., Barker, Alex J., Rousseva, Sylvia, Qiu, Li, Qiu, Xinkai, Klasen, Nathalie, Chiechi, Ryan C., Baran, Derya, Caironi, Mario, Anthopoulos, Thomas D., Portale, Giuseppe, Havenith, Remco W. A., Marrink, Siewert J., Hummelen, Jan C., and Koster, L. Jan Anton

Published
2020
Full Text
View/download PDF

15. Tailorable and Biocompatible Supramolecular-Based Hydrogels Featuring two Dynamic Covalent Chemistries

Author

Marić, Ivana, Yang, Liangliang, Li, Xiufeng, Santiago, Guillermo Monreal, Pappas, Charalampos G., Qiu, Xinkai, Dijksman, Joshua A., Mikhailov, Kirill, van Rijn, Patrick, Otto, Sijbren, Marić, Ivana, Yang, Liangliang, Li, Xiufeng, Santiago, Guillermo Monreal, Pappas, Charalampos G., Qiu, Xinkai, Dijksman, Joshua A., Mikhailov, Kirill, van Rijn, Patrick, and Otto, Sijbren

Abstract

Dynamic covalent chemistry (DCC) has proven to be a valuable tool in creating fascinating molecules, structures, and emergent properties in fully synthetic systems. Here we report a system that uses two dynamic covalent bonds in tandem, namely disulfides and hydrazones, for the formation of hydrogels containing biologically relevant ligands. The reversibility of disulfide bonds allows fiber formation upon oxidation of dithiol-peptide building block, while the reaction between NH−NH2 functionalized C-terminus and aldehyde cross-linkers results in a gel. The same bond-forming reaction was exploited for the “decoration” of the supramolecular assemblies by cell-adhesion-promoting sequences (RGD and LDV). Fast triggered gelation, cytocompatibility and ability to “on-demand” chemically customize fibrillar scaffold offer potential for applying these systems as a bioactive platform for cell culture and tissue engineering.

Published
2023

20. Surface Engineering for Molecular Electronics

Author

Qiu, Xinkai, Qiu, Xinkai, Qiu, Xinkai, and Qiu, Xinkai

Abstract

Molecular electronics studies charge transport through molecules and the applications in electronic devices where molecules serve as the ultimate nanosized building blocks. Controllable charge transport properties and stable electrical junctions lie at the heart of molecular electronics because of their crucial impact on practical devices, and both of them concern engineering at the surface and interface, e.g., anchoring functional molecules onto electrodes and forming densely packed monolayers resistive against electrostatic pressure. This thesis aims to unite the synthesis and characterization of functional (bio)organic semiconductive molecular self-assemblies and the fabrication of electronic devices comprising these ensembles for paradigm-shifting applications from a surface engineering perspective.

Published
2020

23. Amphipathic Side Chain of a Conjugated Polymer Optimizes Dopant Location toward Efficient N-Type Organic Thermoelectrics

Author

Liu, Jian, Ye, Gang, Potgieser, Hinderikus G. O., Koopmans, Marten, Sami, Selim, Nugraha, Mohamad Insan, Villalva, Diego Rosas, Sun, Hengda, Dong, Jingjin, Yang, Xuwen, Qiu, Xinkai, Yao, Chen, Portale, Giuseppe, Fabiano, Simone, Anthopoulos, Thomas D., Baran, Derya, Havenith, Remco W. A., Chiechi, Ryan C., Koster, L. Jan Anton, Liu, Jian, Ye, Gang, Potgieser, Hinderikus G. O., Koopmans, Marten, Sami, Selim, Nugraha, Mohamad Insan, Villalva, Diego Rosas, Sun, Hengda, Dong, Jingjin, Yang, Xuwen, Qiu, Xinkai, Yao, Chen, Portale, Giuseppe, Fabiano, Simone, Anthopoulos, Thomas D., Baran, Derya, Havenith, Remco W. A., Chiechi, Ryan C., and Koster, L. Jan Anton

Abstract

There is no molecular strategy for selectively increasing the Seebeck coefficient without reducing the electrical conductivity for organic thermoelectrics. Here, it is reported that the use of amphipathic side chains in an n-type donor-acceptor copolymer can selectively increase the Seebeck coefficient and thus increase the power factor by a factor of approximate to 5. The amphipathic side chain contains an alkyl chain segment as a spacer between the polymer backbone and an ethylene glycol type chain segment. The use of this alkyl spacer does not only reduce the energetic disorder in the conjugated polymer film but can also properly control the dopant sites away from the backbone, which minimizes the adverse influence of counterions. As confirmed by kinetic Monte Carlo simulations with the host-dopant distance as the only variable, a reduced Coulombic interaction resulting from a larger host-dopant distance contributes to a higher Seebeck coefficient for a given electrical conductivity. Finally, an optimized power factor of 18 mu W m(-1) K-2 is achieved in the doped polymer film. This work provides a facile molecular strategy for selectively improving the Seebeck coefficient and opens up a new route for optimizing the dopant location toward realizing better n-type polymeric thermoelectrics., Funding Agencies|STW/NWOTechnologiestichting STWNetherlands Organization for Scientific Research (NWO) [VIDI 13476]; China Scholarship CouncilChina Scholarship Council; Center for Information Technology of the University of Groningen; Swedish Research CouncilSwedish Research Council [2016-03979]; Olle Engkvists Stiftelse [204-0256]; Advanced Functional Materials center at LiU [2009 00971]; King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) [OSR-CRG2018-3737]; NWO Exact and Natural Sciences [2020/ENW/00852342]

Published
2021
Full Text
View/download PDF

26. Amphipathic Side Chain of a Conjugated Polymer Optimizes Dopant Location toward Efficient N‐Type Organic Thermoelectrics

Author

Liu, Jian, primary, Ye, Gang, additional, Potgieser, Hinderikus G. O., additional, Koopmans, Marten, additional, Sami, Selim, additional, Nugraha, Mohamad Insan, additional, Villalva, Diego Rosas, additional, Sun, Hengda, additional, Dong, Jingjin, additional, Yang, Xuwen, additional, Qiu, Xinkai, additional, Yao, Chen, additional, Portale, Giuseppe, additional, Fabiano, Simone, additional, Anthopoulos, Thomas D., additional, Baran, Derya, additional, Havenith, Remco W. A., additional, Chiechi, Ryan C., additional, and Koster, L. Jan Anton, additional

Published
2020
Full Text
View/download PDF

29. Rectification of current responds to incorporation of fullerenes into mixed-monolayers of alkanethiolates in tunneling junctions† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc04799h Click here for additional data file

Author

Qiu, Li, Zhang, Yanxi, Krijger, Theodorus L., Qiu, Xinkai, Hof, Patrick van't, Hummelen, Jan C., and Chiechi, Ryan C.

Subjects
Chemistry
Abstract

This paper describes the rectification of current through molecular junctions comprising self-assembled monolayers of decanethiolate through the incorporation of C60 fullerene moieties in junctions using eutectic Ga–In (EGaIn) and Au conducting probe AFM top-contacts., This paper describes the rectification of current through molecular junctions comprising self-assembled monolayers of decanethiolate through the incorporation of C60 fullerene moieties bearing undecanethiol groups in junctions using eutectic Ga–In (EGaIn) and Au conducting probe AFM (CP-AFM) top-contacts. The degree of rectification increases with increasing exposure of the decanethiolate monolayers to the fullerene moieties, going through a maximum after 24 h. We ascribe this observation to the resulting mixed-monolayer achieving an optimal packing density of fullerene cages sitting above the alkane monolayer. Thus, the degree of rectification is controlled by the amount of fullerene present in the mixed-monolayer. The voltage dependence of R varies with the composition of the top-contact and the force applied to the junction and the energy of the lowest unoccupied π-state determined from photoelectron spectroscopy is consistent with the direction of rectification. The maximum value of rectification R = |J(+)/J(–)| = 940 at ±1 V or 617 at ±0.95 V is in agreement with previous studies on pure monolayers relating the degree of rectification to the volume of the head-group on which the frontier orbitals are localized.

Published
2016

30. The Effect of Electrostatic Interaction on n-Type Doping Efficiency of Fullerene Derivatives

Author

Liu, Jian, Maity, Sudeshna, Roosloot, Nathan, Qiu, Xinkai, Qiu, Li, Chiechi, Ryan C., Hummelen, Jan C., von Hauff, Elizabeth, Koster, L. Jan Anton, Liu, Jian, Maity, Sudeshna, Roosloot, Nathan, Qiu, Xinkai, Qiu, Li, Chiechi, Ryan C., Hummelen, Jan C., von Hauff, Elizabeth, and Koster, L. Jan Anton

Abstract

The molecular doping of organic semiconductors represents a key strategy for advancing organic electronic applications. However, the n-doping of organic materials is usually less efficient than p-doping and strategies toward the design of more efficient n-doping still remain less explored. In this contribution, the impact of electrostatic interaction is explored on the doping efficiency of fullerene derivatives. [6,6]-Phenyl-C 61-butyric acid methyl ester (PCBM) and a [60]fulleropyrrolidine with a more polarizable triethylene glycol type side chain (PTEG-1) are employed for a comparative study. It is found that the doping efficiency of lightly doped PCBM layers is limited to a few percent, while doped PTEG-1 films exhibit very high doping efficiency approaching 100%. The enhanced n-doping of PTEG-1 compared with that of PCBM is further substantiated by Raman and Fourier transform infrared spectroscopic studies. The activation energy for charge generation in doped PTEG-1 is much smaller than that of doped PCBM, which confirms a higher probability for dissociation of charge transfer complexes in the former compared to the latter. The enhanced molecular n-doping for PTEG-1 is attributed to the electrostatic interaction between the charge transfer complex and the polar environment offered by the triethylene glycol diether side chain.

Published
2019
Full Text
View/download PDF

37. Protein-Electrode Coupling Can Dominates Efficiency Without Affecting the Mechanism of Electronic Transport – Results From a Cross-Lab Comparative Study of Solid State Protein Junctions

Author

Mukhopadhyay, Sabyasachi, primary, Karuppannan, Senthil Kumar, additional, Guo, Cunlan, additional, Fereiro, Jerry A., additional, Bergren, Adam, additional, Mukundan, Vineetha, additional, Qiu, Xinkai, additional, Ocampo, Olga E. Castañeda, additional, Chen, Xiaoping, additional, Chiechi, Ryan C., additional, McCreery, Richard, additional, Pecht, Israel, additional, Sheves, Mordechai, additional, Pasula, Rupali Reddy, additional, Lim, Sierin, additional, Nijhuis, Christian A., additional, Vilan, Ayelet, additional, and Cahen, David, additional

Published
2019
Full Text
View/download PDF

39. New directions in surface functionalization and characterization: general discussion

Author

Azevedo, Helena S., primary, Braunschweig, Adam B., additional, Chiechi, Ryan C., additional, Claridge, Shelley A., additional, Cronin, Leroy, additional, Diaz Fernandez, Yuri, additional, Feizi, Ten, additional, Hartmann, Laura, additional, Huang, Mia, additional, Miura, Yoshiko, additional, Palma, Matteo, additional, Qiu, Xinkai, additional, Ravoo, Bart Jan, additional, Schmidt, Stephan, additional, Turnbull, W. Bruce, additional, Werner, Carsten, additional, Zheng, Zijian, additional, and Zhou, Dejian, additional

Published
2019
Full Text
View/download PDF

41. In-Place Modulation of Rectification in Tunneling Junctions Comprising Self-Assembled Monolayers

Author

Ai, Yong, Kovalchuk, Andrii, Qiu, Xinkai, Zhang, Yanxi, Kumar, Sumit, Wang, Xintai, Kühnel, Martin, Nørgaard, Kasper, Chiechi, Ryan C., Ai, Yong, Kovalchuk, Andrii, Qiu, Xinkai, Zhang, Yanxi, Kumar, Sumit, Wang, Xintai, Kühnel, Martin, Nørgaard, Kasper, and Chiechi, Ryan C.

Abstract

This paper describes tunneling junctions comprising self-assembled monolayers that can be converted between resistor and diode functionality in-place. The rectification ratio is affected by the hydration of densely packed carboxylic acid groups at the interface between the top-contact and the monolayer. We studied this process by treatment with water and a water scavenger using three different top-contacts, eutectic Ga-In (EGaIn), conducting-probe atomic force microscopy (CP-AFM), and reduced graphene oxide (rGO), demonstrating that the phenomena is molecular in nature and is not platform-speciffc. We propose a mechanism in which the tunneling junctions convert to diode behavior through the lowering of the LUMO, which is suffcient to bring it close to resonance at positive bias, potentially assisted by a Stark shift. This shift in energy is supported by calculations and a change in polarization observed by X-ray photoelectron spectroscopy and Kelvin probe measurements. We demonstrate light-driven modulation using spiropyran as a photoacid, suggesting that any chemical process that is coupled to the release of small molecules that can tightly bind carboxylic acid groups can be used as an external stimulus to modulate rectification. The ability to convert a tunneling junction reversibly between a diode and a resistor via an effect that is intrinsic to the molecules in the junction extends the possible applications of Molecular Electronics to reconfigurable circuits and other new functionalities that do not have direct analogs in conventional semiconductor devices.

Published
2018

45. Self-Regenerating Soft Biophotovoltaic Devices

Author

Qiu, Xinkai, primary, Castañeda Ocampo, Olga, additional, de Vries, Hendrik W., additional, van Putten, Maikel, additional, Loznik, Mark, additional, Herrmann, Andreas, additional, and Chiechi, Ryan C., additional

Published
2018
Full Text
View/download PDF

48. Solar Cells: Enhancing the Performance of the Half Tin and Half Lead Perovskite Solar Cells by Suppression of the Bulk and Interfacial Charge Recombination (Adv. Mater. 35/2018)

Author

Shao, Shuyan, primary, Cui, Yong, additional, Duim, Herman, additional, Qiu, Xinkai, additional, Dong, Jingjin, additional, ten Brink, Gert H., additional, Portale, Giuseppe, additional, Chiechi, Ryan C., additional, Zhang, Shaoqing, additional, Hou, Jianhui, additional, and Loi, Maria Antonietta, additional

Published
2018
Full Text
View/download PDF

49. Enhancing the Performance of the Half Tin and Half Lead Perovskite Solar Cells by Suppression of the Bulk and Interfacial Charge Recombination

Author

Shao, Shuyan, primary, Cui, Yong, additional, Duim, Herman, additional, Qiu, Xinkai, additional, Dong, Jingjin, additional, ten Brink, Gert H., additional, Portale, Giuseppe, additional, Chiechi, Ryan C., additional, Zhang, Shaoqing, additional, Hou, Jianhui, additional, and Loi, Maria Antonietta, additional

Published
2018
Full Text
View/download PDF

50. Enhancing Molecular n‐Type Doping of Donor–Acceptor Copolymers by Tailoring Side Chains

Author

Liu, Jian, primary, Qiu, Li, additional, Alessandri, Riccardo, additional, Qiu, Xinkai, additional, Portale, Giuseppe, additional, Dong, JingJin, additional, Talsma, Wytse, additional, Ye, Gang, additional, Sengrian, Aprizal Akbar, additional, Souza, Paulo C. T., additional, Loi, Maria Antonietta, additional, Chiechi, Ryan C., additional, Marrink, Siewert J., additional, Hummelen, Jan C., additional, and Koster, L. Jan Anton, additional

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results