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11.
Hai -Hang Li Masafumi Inoue Hiroyuki Nishimura Junya Mizutani Eiji Tsuzuki 《Journal of chemical ecology》1993,19(8):1775-1787
Phenolic compounds have been identified as the most common allelochemicals produced by higher plants. Inhibitions of cinnamic acid, its related phenolic derivatives, and abscisic acid (ABA) on seedling growth and seed germination of lettuce were studied.trans-Cinnamic acid, ando-,m-, andp-coumaric acids inhibited the growth of etiolated seedlings of lettuce at concentrations higher than 10–4 M and seed germination above 10–3 M. Coumarin inhibited seedling growth and seed germination at 10–5 M or above. Chlorogenic acid inhibited seedling growth above 10–4 M, but did not inhibit seed germination at 10–5–5×10–3 M. Low concentrations (below 10–3 M) of caffeic and ferulic acids promoted the elongation of hypocotyls, but higher concentrations (over 10–3 M) inhibited seedling growth and seed germination. These phenolic compounds and abscisic acid had additive inhibitory effects both on seedling growth and seed germination. The inhibition on lettuce was reversed by caffeic and ferulic acids at concentrations lower than 10–3 M except for the inhibition of germination by coumarin. These results suggest that in naturetrans-cinnamic acid,o-, m-, p-coumaric acids, coumarin, and chlorogenic acid inhibit plant growth regardless of their concentration. However, caffeic and ferulic acids can either promote or inhibit plant growth according to their concentration. 相似文献
12.
Thermal behaviors of a few kinds of poly(fluoroalkyl methacrylate) prepared by γ-or UV-ray polymerization were investigated by using thermogravimetric measurements with the intermittent analysis of the gaseous products. The degradation of fluoroalkyl methacrylate polymers, monomeric units of which were CH2=C(CH3)COOCH2(CF2CF2)nH, n = 1, 2, and 3, proceeded according to the depolymerization mechanism reproducing the pristine monomer exclusively, but the thermogram in inert atmosphere showed the features of a two-step reaction. Two species of polymer differing in the heat stability were supposed to exist in the polymeric substance produced by γ- or UV-ray irradiation, and the fraction of polymer having lower heat stability increased with the increasing length of the fluoroalkyl ester group. In air, however, the thermogram of poly(fluoroalkyl methacrylate) showed no such a stepwise weight decrease as was observed in inert atomsphere with the elevating temperature, and the temperatures at which the depolymerization was introduced shifted to a much higher region. The results were ascribed to the reaction of initiating polymer radicals produced on polymer having lower stability with oxygen to form hydroperoxide, which once stabilized the polymer radicals and obstructed the initiaition of the unzipping reaction till higher temperature. 相似文献
13.
Thermal behaviors of a few kinds of poly(fluoroalkyl methacrylate-co-methyl methacrylate) prepared by γ-ray copolymerization were investigated by using thermogravimetric measurements together with the intermittent analysis of the gaseous products. The thermal degradation of copolymers composed of one of fluoroalkyl methacrylates of the following structures: CH2?C(CH3)COOCH2(CF2CF2)nH, where n = 1,2, and 3, and methyl methacrylate proceeded according to the depolymerization mechanism reproducing the pristine component comonomers exclusively, but their thermograms in inert atmosphere showed the feature of a two-step reaction. In air, however, thermograms of copolymers did not show such a stepwise decrease in weight with the elevating temperature, and temperatures at which depolymerization was introduced shifted to a much higher region. The overall aspects of depolymerization of copolymers seemed to be much similar to that of fluoroalkyl methacrylate homopolymer previously reported, and the retardation of depolymerization by air was considered to be due mainly to the stabilization of once-formed polymer radicals by oxygen. 相似文献
14.
Development of flexible displays using back‐channel‐etched In–Sn–Zn–O thin‐film transistors and air‐stable inverted organic light‐emitting diodes 下载免费PDF全文
Mitsuru Nakata Genichi Motomura Yoshiki Nakajima Tatsuya Takei Hiroshi Tsuji Hirohiko Fukagawa Takahisa Shimizu Toshimitsu Tsuzuki Yoshihide Fujisaki Toshihiro Yamamoto 《Journal of the Society for Information Display》2016,24(1):3-11
We developed flexible displays using back‐channel‐etched In–Sn–Zn–O (ITZO) thin‐film transistors (TFTs) and air‐stable inverted organic light‐emitting diodes (iOLEDs). The TFTs fabricated on a polyimide film exhibited high mobility (32.9 cm2/Vs) and stability by utilization of a solution‐processed organic passivation layer. ITZO was also used as an electron injection layer (EIL) in the iOLEDs instead of conventional air‐sensitive materials. The iOLED with ITZO as an EIL exhibited higher efficiency and a lower driving voltage than that of conventional iOLEDs. Our approach of the simultaneous formation of ITZO film as both of a channel layer in TFTs and of an EIL in iOLEDs offers simple fabrication process. 相似文献
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16.
Xiao Liu Kaoru Ota Anfeng Liu Zhigang Chen 《Peer-to-Peer Networking and Applications》2016,9(4):692-711
Crowd sensing networks can be used for large scale sensing of the physical world or other information service by leveraging the available sensors on the phones. The collector hopes to collect as much as sensed data at relatively low cost. However, the sensing participants want to earn much money at low cost. This paper examines the evolutionary process among participants sensing networks and proposes an evolutionary game model to depict collaborative game phenomenon in the crowd sensing networks based on the principles of game theory in economics. A effectively incentive mechanism is established through corrected the penalty function of the game model accordance with the cooperation rates of the participant, and corrected the game times in accordance with it’s payoff. The collector controls the process of game by adjusting the price function. We find that the proposed incentive game based evolutionary model can help decision makers simulate evolutionary process under various scenarios. The crowd sensing networks structure significantly influence cooperation ratio and the total number of participant involved in the game, and the distribution of population with different game strategy. Through evolutionary game model, the manager can select an optimal price to facilitate the system reach equilibrium state quickly, and get the number of participants involved in the game. The incentive game based evolutionary model in crowd sensing networks provides valuable decision-making support to managers. 相似文献
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Yoshiki Nakajima Tatsuya Takei Toshimitsu Tsuzuki Mitsunori Suzuki Hirohiko Fukagawa Toshihiro Yamamoto Shizuo Tokito 《Journal of the Society for Information Display》2009,17(8):629-634
Abstract— A 5.8‐in. wide‐QQVGA flexible color active‐matrix organic light‐emitting‐diode (AMOLED) display consisting of organic thin‐film transistors (OTFTs) and phosphorescent OLEDs was fabricated on a plastic film. To reduce the operating voltage of the OTFTs, Ta2O5 with a high dielectric constant was employed as a gate insulator. Pentacene was used for the semiconductor layer of the OTFTs. This layer was patterned by photolithography and dry‐etched using a dual protection layer of poly p‐xylylene and SiO2 film. Uniform transistor performance was achieved in the OTFT backplane with QQVGA pixels. The RGB emission layers of the pixels were formed by vacuum deposition of phosphorescent small molecules. The resulting display could clearly show color moving images even when it was bent and operated at a low driving voltage (below 15 V). 相似文献
19.
Tetsushi Oka Toyokazu Abe Kaoru Sugita Masao Yokota 《Artificial Life and Robotics》2009,13(2):455-459
This article describes a multimodal command language for home robot users, and a robot system which interprets users’ messages
in the language through microphones, visual and tactile sensors, and control buttons. The command language comprises a set
of grammar rules, a lexicon, and nonverbal events detected in hand gestures, readings of tactile sensors attached to the robots,
and buttons on the controllers in the users’ hands. Prototype humanoid systems which immediately execute commands in the language
are also presented, along with preliminary experiments of faceto-face interactions and teleoperations. Subjects unfamiliar
with the language were able to command humanoids and complete their tasks with brief documents at hand, given a short demonstration
beforehand. The command understanding system operating on PCs responded to multimodal commands without significant delay.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
20.
Tetsushi Oka Toyokazu Abe Kaoru Sugita Masao Yokota 《Artificial Life and Robotics》2009,14(2):219-223
This article considers the success rates in a multimodal command language for home robot users. In the command language, the
user specifies action types and action parameter values to direct robots in multiple modes such as speech, touch, and gesture.
The success rates of commands in the language can be estimated by user evaluations in several ways. This article presents
some user evaluation methods, as well as results from recent studies on command success rates. The results show that the language
enables users without much training to command home robots at success rates as high as 88%–100%. It is also shown that multimodal
commands combining speech and button-press actions included fewer words and were significantly more successful than single-modal
spoken commands. 相似文献