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71.
Hee Jae Hwang Joo Sung Kim Wook Kim Hyunwoo Park Divij Bhatia Eunsong Jee Yoon Sun Chung Do Hwan Kim Dukhyun Choi 《Liver Transplantation》2019,9(17)
A mechanosensitive, visco‐poroelastic polymer ion pump that can rapidly establish a dense electrical double layer via mechanical pressure, thereby significantly enhancing output performance of an ionic triboelectric nanogenerator (iTENG), is described. A working mechanism of an iTENG using a highly mechanosensitive, visco‐poroelastic ion pump is suggested and the optimal characteristics of the polymer ion pump are reported by investigating optical, mechanical, electrical, and electrochemical properties. Surprisingly, the pressure sensitivity of the iTENG reaches 23.3 V kPa?1, which is tens of times the record value. To achieve controlled high‐frequency pulses from an iTENG, kinematic systems using a gear train and a cam are integrated with a single grounded iTENG, which produces a maximum of 600 V and 22 mA (≈2.2 W cm?2) at an input frequency of 1.67 Hz; after power transforming, those values are converted to 1.42 V and 225 mA. A capacitor of 1 mF can be fully charged to 2 V in only 60 s, making it possible to continuously operate a wireless‐communicating self‐powered humidity sensor. Also, due to the high transparency and deformability of the polymer ion pump, a self‐powered transparent tactile sensor is successfully assembled using a 5 × 5 iTENG array. 相似文献
72.
Hyeonwoo Kim Seung‐Un Lee Do Yoon Lee Min Jae Paik Hyejin Na Jaemin Lee Sang Il Seok 《Liver Transplantation》2019,9(47)
Recently, two‐dimensional (2D) structure on three‐dimensional (3D) perovskites (graded 2D/3D) has been reported to be effective in significantly improving both efficiency and stability. However, the electrical properties of the 2D structure as a passivation layer on the 3D perovskite thin film and resistance to the penetration of moisture may vary depending on the length of the alkyl chain. In addition, the surface defects of the 2D itself on the 3D layer may also be affected by the correlation between the 2D structure and the hole conductive material. Therefore, systematic interfacial study with the alkyl chain length of long‐chained alkylammonium iodide forming a 2D structure is necessary. Herein, the 2D interfacial layers formed are compared with butylammonium iodide (BAI), octylammonium iodide (OAI), and dodecylammonium iodide (DAI) iodide on a 3D (FAPbI3)0.95(MAPbBr3)0.05 perovskite thin film in terms of the PCE and humidity stability. As the length of the alkyl chain increased from BA to OA to DA, the electron‐blocking ability and humidity resistance increase significantly, but the difference between OA and DA is not large. The PSC post‐treated with OAI has slightly higher PCE than those treated with BAI and DAI, achieving a certified stabilized efficiency of 22.9%. 相似文献
73.
Tran Cuong Manh Van Pham Hai Nguyen Hien Thuy Nguyen Thuy Thi Vu Lam Dinh Do Tung Hoang 《Plasmonics (Norwell, Mass.)》2019,14(6):1587-1592
Plasmonics - Since the metamaterial perfect absorber (MPA) is composed of electromagnetic resonance structures, the main operational mechanism of the MPA is electromagnetic resonance. In this work,... 相似文献
74.
Jeongjoo Lee You‐Hyun Seo Sung‐Nam Kwon Do‐Hyung Kim Seokhoon Jang Hyeonwoo Jung Youngu Lee Hasitha Weerasinghe Taehyo Kim Jin Young Kim Doojin Vak Seok‐In Na 《Liver Transplantation》2019,9(36)
The record efficiency of the state‐of‐the‐art polymer solar cells (PSCs) is rapidly increasing, due to the discovery of high‐performance photoactive donor and acceptor materials. However, strong questions remain as to whether such high‐efficiency PSCs can be produced by scalable processes. This paper reports a high power conversion efficiency (PCE) of 13.5% achieved with single‐junction ternary PSCs based on PTB7‐Th, PC71BM, and COi8DFIC fabricated by slot‐die coating, which shows the highest PCE ever reported in PSCs fabricated by a scalable process. To understand the origin of the high performance of the slot‐die coated device, slot‐die coated photoactive films and devices are systematically investigated. These results indicate that the good performance of the slot‐die PSCs can be due to a favorable molecule‐structure and film‐morphology change by introducing 1,8‐diiodooctane and heat treatment, which can lead to improved charge transport with reduced carrier recombination. The optimized condition is then used for the fabrication of large‐area modules and also for roll‐to‐roll fabrication. The slot‐die coated module with 30 cm2 active‐area and roll‐to‐roll produced flexible PSC has shown 8.6% and 9.6%, respectively. These efficiencies are the highest in each category and demonstrate the strong potential of the slot‐die coated ternary system for commercial applications. 相似文献
75.
Jihun Ryu Do Un Hwang Yeon Jae Bae Si Hyeock Lee Young Ho Kim Seung‐Yeol Lee Hee‐Young Jung Kwang Shik Choi 《Entomological Research》2019,49(9):432-435
Pyrethroid insecticides have been effective and powerful for controlling mosquitoes. However, abuse of these insecticides increases the number of resistant mosquitoes. In this study, Culex pipiens pallens and Aedes koreicus were collected from an artificial reservoir in the vicinity of a populated area in Korea, which is also a migratory bird catchment area. To monitor resistance to pyrethroid insecticides in mosquitoes, genomic DNA from the collected mosquitoes was sequenced for the kdr mutation in the voltage‐gated sodium channel (VGSC) gene. As a result, three samples with homozygous resistance (17.6%) and one with heterozygous resistance (5.9%) were found among 17 Cx. pipiens pallens specimens. One of the samples had a unique sequence at the amplified VGSC region. Of the 15 Ae. koreicus, no insecticide resistant individuals were found. In Korea, this is the first report of kdr genetic traits in Ae. koreicus and Cx. pipiens pallens and of a unique VGSC allele in Cx. pipiens pallens. Further investigation is needed to monitor the kdr resistance of these species in Korea and to determine how the unique sequence found in Cx. pipiens pallens is related to insecticide resistance. 相似文献
76.
Amin Soltangheisi Paul J. A. Withers Paulo Sergio Pavinato Maurício Roberto Cherubin Raffaella Rossetto Janaina Braga Do Carmo Gustavo Casoni da Rocha Luiz Antonio Martinelli 《Global Change Biology Bioenergy》2019,11(12):1444-1455
Phosphorus (P) use in global food and bioenergy production needs to become more efficient and sustainable to reduce environmental impacts and conserve a finite and critical resource (Carpenter & Bennett, Environmental Research Letters, 2011, 6, 014009; Springmann et al., Nature, 2018, 562, 519). Sugarcane is one crop with a large P footprint because production is centered on P‐fixing soils with low P availability (Roy et al., Nature Plants, 2016, 2, 16043; Withers et al., Scientific Reports, 2018, 8, 2537). As global demand for processed sugar and bioethanol continues to increase, we advocate that improving P efficiency could become a key sustainability goal for the sugarcane industry. Here, we applied the 5R global P stewardship framework (Withers et al., Ambio, 2015, 44, 193) to identify more sustainable options to manage P in Brazilian sugarcane production. We show that current inputs of P fertilizer to the current crop area could be reduced by over 305 Gg, or 63%, over the next three decades by reducing unnecessary P fertilizer use, better utilization of recyclable bioresources and redesigning recommendation systems. Adoption of these 5R options would save the sugarcane industry in Brazil 528 US$ million and help safeguard global food and energy security. 相似文献
77.
78.
Do YS Smeenk J Broer KM Kisting CJ Brown R Heindel TJ Bobik TA DiSpirito AA 《Biotechnology and bioengineering》2007,97(2):279-286
To examine the potential use of synthesis gas as a carbon and energy source in fermentation processes, Rhodospirillum rubrum was cultured on synthesis gas generated from discarded seed corn. The growth rates, growth and poly-beta-hydroxyalkanoates (PHA) yields, and CO oxidation/H(2) evolution rates were evaluated in comparison to the rates observed with an artificial synthesis gas mixture. Depending on the gas conditioning system used, synthesis gas either stimulated or inhibited CO-oxidation rates compared to the observations with the artificial synthesis gas mixture. Inhibitory and stimulatory compounds in synthesis gas could be removed by the addition of activated charcoal, char-tar, or char-ash filters (char, tar, and ash are gasification residues). In batch fermentations, approximately 1.4 mol CO was oxidized per day per g cell protein with the production of 0.75 mol H(2) and 340 mg PHA per day per g cell protein. The PHA produced from R. rubrum grown on synthesis gas was composed of 86% beta-hydroxybutyrate and 14% beta-hydroxyvalerate. Mass transfer of CO into the liquid phase was determined as the rate-limiting step in the fermentation. 相似文献
79.
Caws M Dang TM Torok E Campbell J Do DA Tran TH Nguyen vV Nguyen TC Farrar J 《PloS one》2007,2(11):e1173
Background
Tuberculous meningitis (TBM) is a devastating condition. The rapid instigation of appropraite chemotherapy is vital to reduce morbidity and mortality. However rapid diagnosis remains elusive; smear microscopy has extremely low sensitivity on cerebrospinal fluid (CSF) in most laboratories and PCR requires expertise with advanced infrastructure and has sensitivity of only around 60% under optimal conditions. Neither technique allows for the microbiological isolation of M. tuberculosis and subsequent drug susceptibility testing. We evaluated the recently developed microscopic observation drug susceptibility (MODS) assay format for speed and accuracy in diagnosing TBM.Methodology/Principal Findings
Two hundred and thirty consecutive CSF samples collected from 156 patients clinically suspected of TBM on presentation at a tertiary referal hospital in Vietnam were enrolled into the study over a five month period and tested by Ziehl-Neelsen (ZN) smear, MODS, Mycobacterial growth Indicator tube (MGIT) and Lowenstein-Jensen (LJ) culture. Sixty-one samples were from patients already on TB therapy for >1day and 19 samples were excluded due to untraceable patient records. One hundred and fifty samples from 137 newly presenting patients remained. Forty-two percent (n = 57/137) of patients were deemed to have TBM by clinical diagnostic and microbiological criteria (excluding MODS). Sensitivity by patient against clinical gold standard for ZN smear, MODS MGIT and LJ were 52.6%, 64.9%, 70.2% and 70.2%, respectively. Specificity of all microbiological techniques was 100%. Positive and negative predictive values for MODS were 100% and 78.7%, respectively for HIV infected patients and 100% and 82.1% for HIV negative patients. The median time to positive was 6 days (interquartile range 5–7), significantly faster than MGIT at 15.5 days (interquartile range 12–24), and LJ at 24 days (interquartile range 18–35 days) (P<0.01).Conclusions
We have shown MODS to be a sensitive, rapid technique for the diagnosis of TBM with high sensitivity, ease of performance and low cost (0.53 USD/sample). 相似文献80.