检索结果-南通市图书馆

Bifurcation Analysis of the Voltage Controlled Photosensitive Chaotic Oscillator

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2013年第6期30卷 42-45页

作者： Van Ha Nguyen han jung Song Department of Nano Systems Engineering Inje UniversityGimhae 621-749Korea Center for Nano Manufacturing Inje UniversityGimhae 621-749Korea

A photosensitive chaotic oscillator which can be controlled with light illumination under various control voltage levels is *** oscillator consists of a photodiode for the light input,clock switches and capacitors for the sample and hold function,a nonlinear function that creates an adjustable chaos map,and a voltage shifter that adjusts the output voltage for *** optimizing the photodiode sub-circuit by using an available photodiode model in PC-based simulation program with integrated circuit emphasis to obtain a suitable output,the full chaotic circuit is verified with standard 0.6-μm complementary metal oxide semiconductor *** dynamics are analyzed as a function of the light intensity under different control voltage *** time series,frequency spectra,transitions in state spaces,bifurcation diagrams and the largest Lyapunov exponent are improved.

关键词： oscillator chaotic function

Flexible micro-LED display and its application in Gbps multi-channel visible light communication

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Flexible Electronics 2022年第1期6卷 973-979页

作者： Luhing Hu Jaeyong Choi Sumin Hwangbo Do-Hoon Kwon Bongkyun jang Seunghyeon Ji Jae-Hyun Kim Sang-Kook han Jong-Hyun Ahn School of Electrical and Electronic Engineering Yonsei UniversitySeoul 03722Republic of Korea Department of Nanomechanics Nano-Convergence Mechanical Systems Research DivisionKorea Institute of Machinery&Materials(KIMM)156 Gajeongbuk-roYuseong-guDaejeon 34103Republic of Korea

A flexible full-color micro-LED display with high mechanical robustness was fabricated by printing quantum dots(QDs)on a blue micro-LED array using standard *** red and green colors yielded from QDs exhibit a better color gamut than conventional color *** light conversion efficiency was enhanced by adding TiO2 nanoparticles to the QD-photoresist *** full-color micro-LED display was successfully mounted on various unusual substrates such as curved glass,fabrics,and human skin,enabling diverse optoelectronic *** addition,wireless multi-channel visible light communication(VLC)based on the wavelength-division-multiplexing orthogonal-frequency-division-multiplexing(WDM-OFDM)technique was demonstrated using a QD-based color micro-LED panel.A high data transmission rate of 1.9 Gbps was successfully obtained owing to the high electrical-optical modulation bandwidth of the QD-based micro-LED panel.

关键词： communication Gbps visible

Iatrogenic atlantoaxial rotatory subluxation after thyroidectomy in a pediatric patient:A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2023年第14期11卷 3351-3355页

作者： Woo-Joon Hong jung-Kil Lee Jong-Hwan Hong Moon-Soo han Shin-Seok Lee Department of Neurosurgery Chonnam National University Hospital&Medical SchoolGwangju 61469South Korea Department of Rheumatology Department of Internal MedicineChonnam National University Medical School&HospitalGwangju 61469South Korea

BACKGROUND Atlantoaxial rotatory subluxation(AARS)is an uncommon disease with a greater prevalence among children than adults,and it is mostly associated with *** spinal injury accounts for a low percentage of ***,in AARS,20%-40%of cases are associated with surgery,and 48%are caused by ***,we describe our experience with a case of iatrogenic AARS after general *** SUMMARY A 12-year-old girl presented with right-sided torticollis and cervical motion *** patient had undergone thyroidectomy 2 mo *** tomography revealed AARS with bilateral locked *** the failure of repeated external reduction under general anesthesia,the patient underwent an open surgical *** patient gained atlantoaxial alignment without any ***-up radiographs showed a normal appearance without *** cervical spine of children is more predisposed to injury due to anatomical and biomechanical *** secondary to infection and surgery is known as Grisel’s syndrome,which involves non-traumatic *** cases of AARS after surgery and other procedures with no evidence of inflammation have been *** experience shows that surgery requiring hyperextension of the neck after general anesthesia should also be included as a risk *** Surgeons and anesthesiologists should be careful not to excessively extend the neck during pediatric ***,clinicians caring for pediatric patients with recent head and neck procedures must be aware of common AARS presentations.

关键词： Atlantoaxial joint Joint subluxation Adolescent Grisel’s syndrome Case report

Solar-harvesting lead halide perovskite for artificial photosynthesis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第11期30卷 11-26,I0001页

作者： Sunje Lee Gyu Yong jang jung Kyu Kim Jong Hyeok Park Department of Chemical and Biomolecular Engineering Yonsei University50 Yonsei-roSeodaemun-guSeoul 03722Republic of Korea School of Chemical Engineering Sungkyunkwan University(SKKU)2066 Seobu‐roJangan‐guSuwon 16419Republic of Korea

Facing the upcoming energy and environmental crisis, artificial photosynthesis for producing various solar fuels (e.g., hydrogen or carbon products) via a solar-to-chemical energy conversion is receiving increasing attention;however, its low conversion efficiency is a challenge for commercialization. To resolve low-efficiency issues, lead halide perovskite (LHP) with outstanding optoelectronic properties compared to conventional semiconductors can be a promising approach to improve the solar-to-fuel conversion reactions and solar fuel production efficiency. The tunable energy band structure and charge transport properties of LHP have promoted their extensive use in the production of solar fuels. This study summarizes the recent advancements of LHP-mediated solar-to-fuel conversions, classified by their redox reactions, namely solar water splitting, hydrohalic acid splitting, and CO_(2) reduction. Advanced approaches for achieving high conversion efficiency and long-term durability are discussed, including the configuration of devices, the composition of LHP, and the protection strategy of LHP. Moreover, the reaction mechanisms of LHP-mediated solar-to-chemical energy conversions and obstacles for enhancing the conversion efficiency are discussed. Finally, we present the perspectives on the development of LHP-incorporated solar-to-fuel conversion systems, which might open a new era of energy harvesting and storage.

关键词： Perovskite Photocatalytic reaction Photoelectrochemistry Photovoltaic Water splitting HI splitting CO_(2)reduction

Supramolecular Polymer Intertwined Free-Standing Bifunctional Membrane Catalysts for All-Temperature Flexible Zn-Air Batteries

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2022年第11期14卷 341-360页

作者： Nayantara K.Wagh Sambhaji S.Shinde Chi Ho Lee Sung-Hae Kim Dong-Hyung Kim han-Don Um Sang Uck Lee jung-Ho Lee Department of Materials Science and Chemical Engineering Hanyang UniversityAnsanRepublic of Korea Department of Applied Chemistry Center for Bionano Intelligence Education and ResearchHanyang UniversityAnsanRepublic of Korea Department of Chemical Engineering Kangwon National UniversityChuncheonGangwon 24341Republic of Korea

Rational construction of flexible free-standing electrocatalysts featuring long-lasting durability,high efficiency,and wide temperature tolerance under harsh practical operations are fundamentally significant for commercial zinc-air ***,3D flexible free-standing bifunctional membrane electrocatalysts composed of covalently cross-linked supramolecular polymer networks with nitrogen-deficient carbon nitride nanotubes are fabricated(referred to as PEMAC@NDCN)by a facile self-templated ***@NDCN demonstrates the lowest reversible oxygen bifunctional activity of 0.61 V with exceptional long-lasting durability,which outperforms those of commercial Pt/C and RuO_(2).Theoretical calculations and control experi-ments reveal the boosted electron transfer,electrolyte mass/ion transports,and abundant active surface site ***,the constructed alkaline Zn-air battery with PEMAC@NDCN air-cathode reveals superb power density,capacity,and discharge-charge cycling stability(over 2160 cycles)compared to the reference Pt/C+RuO_(2).Solid-state Zn-air batteries enable a high power density of 211 mW cm^(−2),energy density of 1056 Wh kg^(−1),stable charge-discharge cycling of 2580 cycles for 50 mA cm^(−2),and wide temperature tolerance from−40 to 70℃with retention of 86%capacity compared to room-temperature counterparts,illustrating prospects over harsh operations.

关键词： Flexible free-standing membrane electrocatalysts Supramolecular polymer Alkaline and flexible solid-state Zn-air batteries All-temperature operations High capacity and energy density

Corrugated surface microparticles with chitosan and levofloxacin for improved aerodynamic performance

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Pharmaceutical Sciences 2023年第3期18卷 146-158页

作者： Chang-Soo han Ji-Hyun Kang Eun hye Park Hyo-jung Lee So-Jeong Jeong Dong-Wook Kim Chun-Woong Park College of Pharmacy Chungbuk National UniversityCheongju 28160Republic of Korea School of Pharmacy Jeonbuk National UniversityJeonju 54896Republic of Korea College of Pharmacy Wonkwang UniversityIksan 54538Republic of Korea

Corrugated surface microparticles comprising levofloxacin(LEV),chitosan and organic acid were prepared using the 3-combo spray drying *** amount and the boiling point of the organic acid affected the degree of *** this study,we tried to improve the aerodynamic performance and increase aerosolization by corrugated surface microparticle for lung drug delivery efficiency as dry powder ***175 L20 prepared with 175 mmol propionic acid solution was corrugated more than HMF175 L20 prepared with 175 mmol formic acid *** ACI and PIV results showed a significant increase in aerodynamic performance of corrugated *** FPF value of HMP175 L20 was 41.3%±3.9%compared with 25.6%±7.7%of HMF175 *** microparticles also showed better aerosolization,decreased x-axial velocity,and variable *** dissolution of drug formulationswas observed in *** administered to the lungs achieved higher LEV concentrations in the lung fluid than high doses administered *** modification in the polymer-based formulation was achieved by controlling the evaporation rate and improving the inhalation efficiency of DPIs.

关键词： Chitosan Organic acid Levofloxacin Corrugated surface Aerodynamic performance

Single atom and defect engineering of CuO for efficient electrochemical reduction of CO_(2) to C_(2)H_(4)

在线全文

学校读者我要写书评

暂无评论

SmartMat 2022年第1期3卷 194-205页

作者： Senlin Chu Changwoo Kang Woonghyeon Park Yu han Song Hong Leiduan Hao Hao Zhang Tsz Woon Benedict Lo Alex W.Robertson Yousung jung Buxing han Zhenyu Sun State Key Laboratory of Organic‐Inorganic Composites Beijing University of Chemical TechnologyBeijingChina Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)DaejeonRepublic of Korea Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityHong KongChina Department of Physics University of WarwickCoventryUK Institute of Chemistry Chinese Academy of SciencesBeijingChina

Electrochemical CO_(2) transformation to high‐value ethylene(C_(2)H_(4))at high currents and efficiencies is desired and yet remains a grand *** show for the first time that coupling single Sb atoms and oxygen vacancies of CuO enable synergistic electrocatalytic reduction of CO_(2) to C_(2)H_(4) at low *** dispersed Sb atoms occupying metal substitutional sites of CuO are synthesized under mild *** overall CO_(2) reduction faradaic efficiency(FE)reaches 89.3±1.1%with an FE toward C_(2)H_(4) exceeding 58.4%at a high‐current density of 500 mA/cm^(2).Addition of the p‐block metal is found to induce transformation of CuO from flakes to nanoribbons rich in nanoholes and oxygen vacancies,greatly enhancing CO_(2) adsorption and activation while suppressing hydrogen *** density functional theory calculations with in situ X‐ray diffraction reveal that combining Sb sites and oxygen vacancies prominently lessen the dimerization energy of adsorbed CO intermediate,thus boosting the conversion of CO_(2) to produce C_(2)H_(4).This study provides a new perspective for promoting selective C-C coupling for electrochemical CO_(2) reduction.

关键词： CO_(2)reduction copper oxide electrocatalysis ethylene single sites

Selecting suitable sites for mountain ginseng(Panax ginseng)cultivation by using geographically weighted logistic regression

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

山地科学学报（英文） 2017年第3期14卷 492-500页

作者： han Hee jang Kwang-min CHUNG Joo-sang Department of Forest Engineering Resources and ManagementCollege of ForestryOregon State UniversityCorvallisOR 97331USA Department of Forest Sciences College of Agriculture and Life SciencesSeoul National UniversitySeoul 08826Republic of Korea Research Institute for Agriculture and Life Sciences Seoul National UniversitySeoul 08826Republic of Korea

With the well-being trends to pursue a healthy life, mountain ginseng(Panax ginseng) is rising as one of the most profitable forest products in South Korea. This study was aimed at evaluating a new methodology for identifying suitable sites for mountain ginseng cultivation in the country. Forest vegetation data were collected from 46 sites and the spatial distribution of all sites was analyzed using GIS data for topographic position, landform, solar radiation, and topographic wetness. The physical and chemical properties of the soil samples, including moisture content, p H, organic matter, total nitrogen, exchangeable cations, available phosphorous, and soil texture, were analyzed. The cultivation suitability at each site was assessed based on the environmental conditions using logistic regression(LR) and geographically weighted logistic regression(GWLR) and the results of both methods were compared. The results show that the areas with northern aspect and higher levels of solar radiation, moisture content, total nitrogen, and sand ratio are more likely to be identified as suitable sites for ginseng cultivation. In contrast to the LR, the spatial modeling with the GWLR results in an increase in the model fitness and indicates that a significant portion of spatialautocorrelation in the data decreases. A higher value of the area under the receiver operating characteristic(ROC) curve presents a better prediction accuracy of site suitability by the GWLR. The geographically weighted coefficient estimates of the model are nonstationary, and reveal that different site suitability is associated with the geographical location of the forest stands. The GWLR increases the accuracy of selecting suitable sites by considering the geographical variations in the characteristics of the cultivation sites.

关键词：人参属人参地点适用性逻辑回归地理上加权的逻辑回归地理信息系统南朝鲜

Electrochemical characteristics of stainless steel using impressed current cathodic protection in seawater

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第4期19卷 930-934页

作者： Seok-Ki jang Min-Su han Seong-Jong KIM Division of Marine Engineering Mokpo Maritime University

Stainless steels such as STS 304,316 and 630 are frequently used as shaft materials in small fiber reinforced polymer(FRP) fishing *** the shaft material is exposed to a severely corrosive environment such as seawater,it should be protected using appropriate *** impressed current cathodic protection was used to inhibit corrosion in shaft *** anodic polarization,passivity was remarkably more evident in STS 316 stainless steel than in STS 304 and STS *** pitting potentials of STS 304,316,and 630 stainless steels were 0.30,0.323,and 0.260 V,*** concentration polarization due to oxygen reduction and activation polarization due to hydrogen generation were evident in the cathodic polarization trends of all three stainless *** 316 had the lowest current densities in all potential ranges,and STS 630 had the *** analysis showed that STS 316 was the most noble in the *** addition,the corrosion current density was the lowest for STS 316.

关键词：外加电流阴极保护 316不锈钢电化学特性海水腐蚀电流密度材料腐蚀阳极极化 STS