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91.
Mengjiao Li Feng‐Shou Yang Yung‐Chi Hsiao Che‐Yi Lin Hsing‐Mei Wu Shih‐Hsien Yang Hao‐Ruei Li Chen‐Hsin Lien Ching‐Hwa Ho Heng‐Jui Liu Wenwu Li Yen‐Fu Lin Ying‐Chih Lai 《Advanced functional materials》2019,29(19)
Electronics based on layered indium selenide (InSe) channels exhibit promising carrier mobility and switching characteristics. Here, an InSe tribotronic transistor (denoted as w/In InSe T‐FET) obtained through the vertical combination of an In‐doped InSe transistor and triboelectric nanogenerator is demonstrated. The w/In InSe T‐FET can be operated by adjusting the distance between two triboelectrification layers, which generates a negative electrostatic potential that serves as a gate voltage to tune the charge carrier transport behavior of the InSe channel. Benefiting from the surface charging doping of the In layer, the w/In InSe T‐FET exhibits high reliability and sensitivity with a large on/off current modulation of 106 under a low drain–source voltage of 0.1 V and external frictional force. To demonstrate its function as a power‐saving tactile sensor, the w/In InSe T‐FET is used to sense “INSE” in Morse code and power on a light‐emitting diode. This work reveals the promise of 2D material–based tribotronics for use in nanosensors with low power consumption as well as in intelligent systems. 相似文献
92.
Reversible and Precisely Controllable p/n‐Type Doping of MoTe2 Transistors through Electrothermal Doping
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Yuan‐Ming Chang Shih‐Hsien Yang Che‐Yi Lin Chang‐Hung Chen Chen‐Hsin Lien Wen‐Bin Jian Keiji Ueno Yuen‐Wuu Suen Kazuhito Tsukagoshi Yen‐Fu Lin 《Advanced materials (Deerfield Beach, Fla.)》2018,30(13)
Precisely controllable and reversible p/n‐type electronic doping of molybdenum ditelluride (MoTe2) transistors is achieved by electrothermal doping (E‐doping) processes. E‐doping includes electrothermal annealing induced by an electric field in a vacuum chamber, which results in electron (n‐type) doping and exposure to air, which induces hole (p‐type) doping. The doping arises from the interaction between oxygen molecules or water vapor and defects of tellurium at the MoTe2 surface, and allows the accurate manipulation of p/n‐type electrical doping of MoTe2 transistors. Because no dopant or special gas is used in the E‐doping processes of MoTe2, E‐doping is a simple and efficient method. Moreover, through exact manipulation of p/n‐type doping of MoTe2 transistors, quasi‐complementary metal oxide semiconductor adaptive logic circuits, such as an inverter, not or gate, and not and gate, are successfully fabricated. The simple method, E‐doping, adopted in obtaining p/n‐type doping of MoTe2 transistors undoubtedly has provided an approach to create the electronic devices with desired performance. 相似文献
93.
A Nanostructuring Method to Decouple Electrical and Thermal Transport through the Formation of Electrically Triggered Conductive Nanofilaments
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José Ramón Durán Retamal Chen‐Fang Kang Der‐Hsien Lien Wei‐Cheng Kuo Zhen‐Yu Juang Meng‐Lin Tsai Chih‐Hsiang Ho Jenh‐Yih Juang Vincent K. S. Hsiao Ying‐Hao Chu Lain‐Jong Li Yue Wu Jr‐Hau He 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Transforming thermal energy into electric energy and vice versa needs the decoupling of electrical transport from thermal transport. An innovative strategy is proposed by forming/disrupting electrically triggered conductive nanofilaments within semiconducting thin films to switch thermoelectric properties between two states without further material modification and manufacturing processes. It can also controllably adjust the degree of decoupling, providing a potential resolution and performance adjustability for heat/coldness control or power consumption reduction on demand. 相似文献
94.
Meng Yu Tsai Ko Chun Lee Che Yi Lin Yuan Ming Chang Kenji Watanabe Takashi Taniguchi Ching Hwa Ho Chen Hsin Lien Po Wen Chiu Yen Fu Lin 《Advanced functional materials》2021,31(40):2105345
In bionic technology, it has become an innovative process imitating the functionality and structuralism of human biological systems to exploit advanced artificial intelligent machines. Bionics plays a significant role in environmental protection, especially for its low energy loss. By fusing the concept of receptor-like sensing component and synapse-like memory, the photoactive electro-controlled optical sensory memory (PE-SM) is proposed and realized in a single device, which endows a simple methodology of reducing power consumption by photoactive electro-control. The PE-SM is the system built with the stacked atomically thick materials, in which rhenium diselenide serves as a robust photosensor, hexagonal boron nitride serves as a tunneling dielectric, and graphene serves as a charge-storage layer. With the features of the PE-SM, it performs synaptic metaplasticities under optical spikes. In addition, a simulated spiking neural network composed of 24 × 24 PE-SMs is further presented in an unsupervised machine learning environment, performing image recognition via the Hebbian rule. The PE-SM not only improves the neuromorphic computing efficiency but also simplifies the circuit-size structure. Eventually, the concept of photoactive electro-control can extend to other photosensitive 2D materials and provide a new approach of constructing either visual perception memory or photonic synaptic devices. 相似文献
95.
The formation of Mannich bases from secondary aliphatic amines and primary alkoxymethyl compounds of urea and melamine in basic media have been studied. The rate of formation of the Mannich base is equal to the rate of decomposition of the alkoxymethyl compound. This is explained by a reaction of the amine with the Schiff base, the intermediate formed during the alkoxymethyl decomposition. In a mixture of primary alkoxymethyl and hydroxymethyl compounds of urea and melamine, the amine reacts almost selectively with the alkoxymethyl compound. An analytical method for the determination of primary dimethylene ether groups of primary alkoxymethyl groups in mixture with hydroxymethyl groups is developed. 相似文献
96.
Chun‐Teh Li Renbo Yang Minliang Shih Chuh‐Yung Chen Lien‐Te Hsieh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(7):817-823
A radio frequency (RF) plasma system has been used to decompose 1,2‐dichloroethane (DCE). Final products were identified by a Fourier transform infrared (FTIR) spectrometer. The main products of DCE decomposition in O2/Ar plasma were CO2, CO, and HCl. Other minor chlorinated products were CCl4, C2HCl3, C2H3Cl, C2Cl4, CHCl3, C2HCl5, and COCl2. Nonchlorinated products were C2H2, C2H4, C2H6, and HCOOH. The plasma reactor with a brass electrode had a higher decomposition fraction of DCE [η, (Cin ? Cout)/Cin × 100%] than that obtained with other materials (Au, Ni, and Cr). Different electrode configurations (inner and outer) were also evaluated for the decomposition of DCE. Argon plus oxygen was found to be the most suitable carrier/auxiliary gas for DCE decomposition. In addition, operational parameters for DCE decomposition in RF plasma including concentration, operational pressure, and total gas flow rate were evaluated. Copyright © 2003 Society of Chemical Industry 相似文献
97.
Docosahexaenoic acid (DHA, 22∶6n-3) and arachidonic acid (AA, 20∶4n-6) serve important roles in perinatal visual and neural
development. A neonatal pig model was used to determine if dietary supplementation with DHA and AA at slightly greater concentrations
than normally found in human milk would influence fatty acid accretion in retina. One-day-old piglets were assigned to one
of four diets (n=5/group): (i) STD, standard diet containing fat similar to infant formula; (ii) STD+DHA, 0.7% of fatty acids
as DHA; (iii) STD+AA, 0.9% as AA; and (iv) STD+BOTH, 0.8% as DHA plus 1.0% as AA. After 25 d, fatty acids in retina phosphatidylcholine
(PC) and phosphatidylethanolamine (PE) were determined. Supplementation with DHA resulted in approximately twofold increases
(P<0.05) in PC-DHA (4.88% in STD vs. 10.03% in STD+DHA and 9.47% in STD+BOTH). Similarly, AA supplementation increased PC-AA
1.3–1.4-fold (4.47% in STD vs. 6.19% in STD+AA and 5.70% in STD+BOTH). For PE, supplementation with either fatty acid or in
combination resulted in no significant increases, except for a 1.2-fold increase in DHA for STD+BOTH (32.66%) vs. STD (28.38%).
Thus, PC responded to dietary supplementation, with addition of DHA, AA, or BOTH, resulting in increases in respective fatty
acids; PE was less responsive, with only STD+BOTH resulting in increased DHA. No significant competition between DHA and AA
in incorporation into phospholipids was observed. In conclusion, consumption of a combination of DHA and AA by neonatal pigs
supported accretion of DHA in retina phospholipids, while simultaneously supplying the AA necessary for membrane phospholipids
and eicosanoid biosynthesis.
Based on a presentation at the AOCS Annual Meeting & Expo in San Antonio, Texas, May 7–11, 1995. 相似文献
98.
Solution‐Processed High‐Performance Tetrathienothiophene‐Based Small Molecular Blends for Ambipolar Charge Transport
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Sureshraju Vegiraju Chih‐Yu Lin Pragya Priyanka Deng‐Yi Huang Xian‐Lun Luo Hsiang‐Chi Tsai Shao‐Huan Hong Chia‐Jung Yeh Wei‐Chieh Lien Chien‐Lung Wang Shih‐Huang Tung Cheng‐Liang Liu Ming‐Chou Chen Antonio Facchetti 《Advanced functional materials》2018,28(28)
Four soluble dialkylated tetrathienoacene ( TTAR) ‐based small molecular semiconductors featuring the combination of a TTAR central core, π‐conjugated spacers comprising bithiophene ( bT ) or thiophene ( T ), and with/without cyanoacrylate ( CA ) end‐capping moieties are synthesized and characterized. The molecule DbT‐TTAR exhibits a promising hole mobility up to 0.36 cm2 V?1 s?1 due to the enhanced crystallinity of the microribbon‐like films. Binary blends of the p‐type DbT‐TTAR and the n‐type dicyanomethylene substituted dithienothiophene‐quinoid ( DTTQ‐11 ) are investigated in terms of film morphology, microstructure, and organic field‐effect transistor (OFET) performance. The data indicate that as the DbT‐TTAR content in the blend film increases, the charge transport characteristics vary from unipolar (electron‐only) to ambipolar and then back to unipolar (hole‐only). With a 1:1 weight ratio of DbT‐TTAR DTTQ‐11 in the blend, well‐defined pathways for both charge carriers are achieved and resulted in ambipolar transport with high hole and electron mobilities of 0.83 and 0.37 cm2 V?1 s?1, respectively. This study provides a viable way for tuning microstructure and charge carrier transport in small molecules and their blends to achieve high‐performance solution‐processable OFETs. 相似文献
99.
Terahertz (THz) radiation probes intermolecular interactions through crystal lattice vibrations, allowing the characterization of solid materials. Thus, THz spectroscopy is a promising alternative to mainstream solid-state analytical tools such as X-ray diffraction or thermal analysis. The method provides the benefits of online measurement, remote sampling and three-dimensional imaging, all of which are attractive for quality control and security applications. In the context of pharmaceutical solids, THz spectroscopy can differentiate and quantify different forms of active pharmaceutical ingredients. Here, we apply this technique to monitor a dynamic process involving two molecular crystals. In particular, we follow the mechanochemical construction of a two-component cocrystal by grinding together phenazine (phen) and mesaconic acid (mes). To rationalize the observed changes in the spectra, we conduct lattice dynamics calculations that lead to the tentative assignment of at least one feature in the cocrystal THz spectrum. 相似文献
100.
The recently described gastrointestinal glutathione peroxidase (GI-GPx) is the fourth member of the family of the selenoenzymes glutathione peroxidases (GPx). In contrast to the more uniform distribution of, for example, the classical glutathione peroxidase (cGPx), it is expressed exclusively in the gastrointestinal tract and has, therefore, been suggested to function as a primary barrier against alimentary hydroperoxides. In order to get an idea of its relative importance we investigated its position in the hierarchy of selenoprotein expression. The selenium-dependent expression of GI-GPx was analyzed in comparison with that of other GPx types at the level of mRNA and protein in HepG2 and CaCo-2 cells. Furthermore, the selenocysteine insertion sequence (SECIS) efficiencies of GI-GPx, phospholipid hydroperoxide glutathione peroxidase (PHGPx) and cGPx in response to selenium were determined by a reporter-gene assay in human hepatoma cells and baby hamster kidney cells. GI-GPx mRNA levels increased during selenium deficiency, whereas cGPx mRNA levels decreased and PHGPx mRNA levels remained almost unaffected. In cells grown in selenium-poor media, all GPx-types were low in both activity and immunochemical reactivity. Upon selenium repletion immunoreactive GI-GPx protein reached a plateau after 10 h, whereas cGPx started to be expressed at 24 h and did not reach its maximum level before 3 days. SECIS efficiencies decreased in the order PHGPx > cGPx > GI-GPx. The augmentation of SECIS efficiencies by selenium was highest for cGPx and intermediate for PHGPx, whereas it was marginal for GI-GPx. The high mRNA stability under selenium restriction, the speed of biosynthesis upon selenium repletion and the marginal effect of selenium on the SECIS efficiency indicate that of the GPx isotypes, GI-GPx ranks highest in the hierarchy of selenoproteins and point to a vital role of GI-GPx in the gastrointestinal tract. 相似文献