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991.
High charging overpotential (low energy efficiency) is one of the most important challenges preventing the use of current nonaqueous Li–O2 batteries. This study demonstrates direct in situ-incorporation of metal oxides on carbon during synthesis and the associated application to nonaqueous Li–O2 battery catalysts. The partially oxidized Mn3O4 (Mn3O4/Mn5O8)-incorporating carbon cathode shows an average overpotential reduction of ∼8% charge/discharge during 40 cycles in a rechargeable nonaqueous Li–O2 cell. Here, we suggested the possibility that only a small amount of the oxide species (<5%) could show catalytic effects during charge in a rechargeable Li–O2 cell.Only a small amount of manganese oxide species (<5%) in carbon shows catalytic effects during charging in a rechargeable Li–O2 cell. 相似文献
992.
Problems and hopes perceived by mothers,fathers and physicians of children receiving palliative care
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Douglas L. Hill PhD Victoria A. Miller PhD Kari R. Hexem MPH Karen W. Carroll BS Jennifer A. Faerber PhD Tammy Kang MD Chris Feudtner MD PhD MPH 《Health expectations》2015,18(5):1052-1065
Background
The quality of shared decision making for children with serious illness may depend on whether parents and physicians share similar perceptions of problems and hopes for the child.Objective
(i) Describe the problems and hopes reported by mothers, fathers and physicians of children receiving palliative care; (ii) examine the observed concordance between participants; (iii) examine parental perceived agreement; and (iv) examine whether parents who identified specific problems also specified corresponding hopes, or whether the problems were left ‘hopeless’.Method
Seventy‐one parents and 43 physicians were asked to report problems and hopes and perceived agreement for 50 children receiving palliative care. Problems and hopes were classified into eight domains. Observed concordance was calculated between parents and between each parent and the physicians.Results
The most common problem domains were physical body (88%), quality of life (74%) and medical knowledge (48%). The most common hope domains were quality of life (88%), suffering (76%) and physical body (39%). Overall parental dyads demonstrated a high percentage of concordance (82%) regarding reported problem domains and a lower percentage of concordance on hopes (65%). Concordance between parents and physicians regarding specific children was lower on problem (65–66%) and hope domains (59–63%). Respondents who identified problems regarding a child's quality of life or suffering were likely to also report corresponding hopes in these domains (93 and 82%, respectively).Conclusion
Asking parents and physicians to talk about problems and hopes may provide a straightforward means to improve the quality of shared decision making for critically ill children. 相似文献993.
Ji-Hyeon Park R. Nandi Jae-Kwan Sim Dae-Young Um San Kang Jin-Soo Kim Cheul-Ro Lee 《RSC advances》2018,8(37):20585
III-Nitride nanowires are currently considered as next generation photovoltaic materials due to their excellent physical properties together with reduced dislocation densities, increased surface area and thus enhanced light absorption and direct path for carrier transport. Here, we investigate the photovoltaic characteristics of a solar cell fabricated from a novel hybrid nanostructure comprising uniaxial and coaxial InGaN/GaN multi-quantum wells (MQWs) along with an InGaN nano-cap layer. Various characterization methods were employed to study the optical and structural properties of the hybrid nanostructure. Transmission electron microscopy images revealed the hybrid nanostructure consists of distinct uniaxial and coaxial InGaN/GaN MQWs along with the InGaN nano-cap layer. The InGaN/GaN MQW architectures have a significant effect on the performance of the photovoltaic device. The solar cell fabricated with the hybrid nanostructure exhibits superior photovoltaic performance compared to the uniaxial as well as the coaxial InGaN/GaN nanowire MQW structures. The improved photovoltaic characteristic is primarily attributed to the considerably larger InGaN active area grown in the hybrid nanostructure. A conversion efficiency of 1.16% along with a fill factor of 70% was obtained for the device fabricated with the hybrid nanostructure. This study provides an experimental demonstration of the improvement of III-nitride nanowire based solar cells incorporating uniaxial and coaxial InGaN/GaN MQWs.Solar cells fabricated with hybrid nanowires comprising InGaN/GaN uniaxial and coaxial multi-quantum wells with an InGaN nano-cap layer. 相似文献
994.
Min-A. Kang Seulgi Ji Seongjun Kim Chong-Yun Park Sung Myung Wooseok Song Sun Sook Lee Jongsun Lim Ki-Seok An 《RSC advances》2018,8(37):20851
Correction for ‘Highly sensitive and wearable gas sensors consisting of chemically functionalized graphene oxide assembled on cotton yarn’ by Min-A. Kang et al., RSC Adv., 2018, 8, 11991–11996.The authors regret that one of the funding bodies listed in the Acknowledgements section of the original article is incorrect. A revised version of the Acknowledgements section, in which ‘NRF-2016M3A7B4900119’ is replaced by ‘NRF-2017M3D9A1073502’, can be found below.This research was supported by a grant (2011-0031636) from the Center for Advanced Soft Electronics under the Global Frontier Research Program of the Ministry of Science, ICT and Future Planning, Korea. This research was also supported by Nano/Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF-2017M3D9A1073502).The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
995.
Near-infrared (NIR) photoswitching transistors have been fabricated using a hybrid structure of zinc oxide (ZnO) and quantum-dots (QDs). The ZnO active layer was prepared using a solution process, while colloidal QDs were inserted between a silicon dioxide (SiO2) gate insulator and a ZnO active layer. The small band gap QDs (1.59 eV) were used to absorb low-energy NIR photons, generate photo-excited carriers, and inject them into the conduction band of the ZnO film. The device with the interfacial QDs induced photocurrents upon exposure to 780 nm-wavelength light. The photoresponsivity of the ZnO/QD device was 0.06 mA W−1, while that of the device without QDs was 1.7 × 10−5 mA W−1, which indicated that the small band gap QDs enabled a photo-induced current when exposed to NIR light. Furthermore, a photoinverter was prepared which was composed of a ZnO/QDs phototransistor and a load resistor. Photoswitching characteristics indicated that the photoinverter was well modulated by a periodic light signal of 780 nm in wavelength. The results demonstrate a useful way to fabricate NIR optoelectronics based on ZnO and QDs.A near-infrared photoinverter was fabricated based on ZnO and quantum-dots. We found that the small band gap quantum-dots could absorb low-energy near-infrared photons, generate photo-excited carriers, and inject them into the conduction band of ZnO. 相似文献
996.
<正>多重耐药菌即1种微生物对3类(比如氨基糖苷类、红霉素、β-内酰胺类)或3类以上抗菌药物同时耐药。随着抗菌药物应用日益广泛,细菌耐药性已成为国际、国内医院感染和社区感染普遍存在的问题。对于难治性(多重耐药菌感染)创口的治疗,某中医院普通外科采取中医特色自制黄连纱条对难治性感染创口进行治疗。2010—2014年共治疗25例难治性创口感染患者,均已进行分泌物细菌培 相似文献
997.
Myung Hyun Kang Sung Ho Kim Seunghun Jang Ji Eun Lim Hyunju Chang Ki-jeong Kong Sung Myung Joung Kyu Park 《RSC advances》2018,8(50):28447
Silver sulfide nanoparticles (Ag2S NPs) are currently being explored as infrared active nanomaterials that can provide environmentally stable alternatives to heavy metals such as lead. In this paper, we describe the novel synthesis of Ag2S NPs by using a sonochemistry method and the fabrication of photodetector devices through the integration of Ag2S NPs atop a graphene sheet. We have also synthesized Li-doped Ag2S NPs that exhibited a significantly enhanced photodetector sensitivity via their enhanced absorption ability in the UV-NIR region. First-principles calculations based on a density functional theory formalism indicated that Li-doping produced a dramatic enhancement of NIR photoluminescence of the Ag2S NPs. Finally, high-performance photodetectors based on CVD graphene and Ag2S NPs were demonstrated and investigated; the hybrid photodetectors based on Ag2S NPs and Li-doped Ag2S NPs exhibited a photoresponse of 2723.2 and 4146.0 A W−1 respectively under a light exposure of 0.89 mW cm−2 at 550 nm. Our novel approach represents a promising and effective method for the synthesis of eco-friendly semiconducting NPs for photoelectric devices.Silver sulfide nanoparticles (Ag2S NPs) are currently being explored as infrared active nanomaterials that can provide environmentally stable alternatives to heavy metals such as lead. 相似文献
998.
999.
疾病管理可提高医疗的服务质量,减少不必要的医疗费用,执业药师在疾病管理尤其是慢病管理中可发挥重要作用。本文介绍了执业药师在疾病管理中的作用,并提出执业药师在慢病管理中的策略。 相似文献
1000.
Shi Hong Kai Chook Shaun Leow Lowell Lim Shir Lynn Ramanathan Kollengode Kofidis Theo Kang Giap Swee 《Journal of thrombosis and thrombolysis》2021,52(2):680-682
Journal of Thrombosis and Thrombolysis - We present a novel case of a patient with nephrotic syndrome and previous left pneumonectomy who had a massive pulmonary embolism of his remnant right... 相似文献