检索结果-南通市图书馆

Formic acid as an alternative reducing agent for the catalytic nitrate reduction in aqueous media

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第8期25卷 1696-1702页

作者： Eun-kyoung choi Kuy-hyun Park Ho-bin Lee Misun cho Samyoung Ahn Department of Environmental Education Sunchon National University

Formic acid was used for the nitrate reduction as a reductant in the presence of Pd：Cu/γ-alumina catalysts. The surface characteristics of the bimetallic catalyst synthesized by wet impregnation were investigated by SEM, TEM-EDS. The metals were not distributed homogeneously on the surface of catalyst, although the total contents of both metals in particles agreed well with the theoretical values. Formic acid decomposition on the catalyst surface, its influence on solution pH and nitrate removal efficacy was investigated. The best removal of nitrate （50 ppm） was obtained under the condition of 0.75 g/L catalyst with Pd：Cu ratio （4：1） and two fold excess of formic acid. Formic acid decay patterns resembled those of nitrate removal, showing a linear relationship between kf （formic acid decay） and k （nitrate removal）. Negligible amount of ammonia was detected, and no nitrite was detected, possibly due to buffering effect of bicarbonate that is in situ produced by the decomposition of formic acid, and due to the sustained release of H2 gas.

关键词： formic acid catalytic nitrate reduction Pd:Cu/γ-alumina catalyst H2 supply

Nanocomposite quasi-solid-state electrolyte for high-safety lithium batteries

在线全文

学校读者我要写书评

暂无评论

Nano Research 2017年第9期10卷 3092-3102页

作者： hyunji choi hyun Woo Kim Jae-kwang Kim Young Jun Lim Youngsik Kim Jou-Hyeon Ahn School of Energy & Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan 689-798 Republic of Korea Department of Solar & Energy Engineering Cheongju University Cheongju Chungbuk 28503 Republic of Korea School of Energy & Chemical Engineering and Research Institute for Green Energy Convergence Technology Gyeongsang National University 900 Gajwa-dong Jinju 660-70 I Republic of Korea

Rechargeable lithium batteries are attractive power sources for electronic devices and are being aggressively developed for vehicular use. Nevertheless, problems with their safety and reliability must be solved for the large-scale use of lithium batteries in transportation and grid-storage applications. In this study, a unique hybrid solid-state electrolyte composed of an ionic liquid electrolyte (LiTFSI/Pyr14TFSI) and BaTiO3 nanosize ceramic particles was prepared without a polymer. The electrolyte exhibited high thermal stability, a wide electrochemical window, good ionic conductivity of 1.3 × 10−3 S·cm−1 at 30 °C, and a remarkably high lithium-ion transference number of 0.35. The solid-state LiFePO4 cell exhibited the best electrochemical properties among the reported solid-state batteries, along with a reasonable rate capability. Li/LiCoO2 cells prepared using this nanocomposite solid electrolyte exhibited high performance at both room temperature and a high temperature, confirming their potential as lithium batteries with enhanced safety and a wide range of operating temperatures.

关键词： nanocomposition solidified ionic liquid shell charge space safety lithium battery

Distribution of electric field for carbon nanotube assembly: Simulation (I)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 117-120页

作者： Soon-Geun KWON Soo-hyun KIM kwang-Ho KIM Myung-Chang KANG hyung-Woo LEE Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Korea National Core Research Center for Hybrid Materials Solution Pusan National University

The distribution of electric field for the alignment and attachment of carbon nanotubes (CNTs) was simulated. To be attached at the desired place, the aligned and attracted CNTs should be stayed in the desired area called the stable region or the quasi-stable region for an instant where the change of electric field is minimized. Since the conical electrode has the very narrow sized quasi-stable region, few CNTs can be attached. The rectangular electrodes have a wide stable region, so lots of CNTs can be attached. The results indicate that the round electrode which has a proper sized quasi-stable region is more effective for aligning and attaching a single CNT than the conical or rectangular shaped electrodes.

关键词：碳纳米管电场分布数值模拟组装电场变化圆锥形稳定电极

Simulation of Solid Particle Interactions Including Segregated Lamination by Using MPS Method

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2018年第7期116卷 11-29页

作者： Kyung Sung Kim Moo-hyun Kim Hakun Jang Hee Chen cho Tongmyong University BusanRepublic of Korea Texas A&M University College StationTXU.S.A Mississippi State University MSU.S.A

A new MPS(Moving Particle Semi-implicit)method is developed to simulate the behaviors and interactions of multiple fine solid particles as a *** fluid particles are affected by viscosity,so solid particles are affected by *** solid particle dynamics for landslides,dumping,and gravity sorting *** can be difficult to simulate using conventional MPS methods,are modeled in this paper using the developed multi-solid-particle MPS method that benefits from drawing comparisons with the corresponding fluid particle *** present MPS results for dumping solid particles are verified against the corresponding DEM(Discrete Element Method)*** shape and angle of repose for solid particles are shown to be highly dependent on the friction coefficient between *** peculiar phenomenon of segregated lamination(gravity sorting)among grains of different densities has been successfully reproduced using the multi-solid-particle MPS *** quality is found to be dependent on the densities and frictional coefficients of the constituent *** behavior of heterogeneous mixtures of multiple solid and liquid particles are also compared and *** newly developed tool offers a window into the physical dynamics of sedimentology that the broader geoscience community might benefit from.

关键词： Fine solid particle MPS(Moving Particle Semi-implicit) friction force land sliding dumping segregated lamination heterogeneous multiple particles gravity sorting

Simultaneous bilateral acromial base fractures after staged reverse total shoulder arthroplasty: 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 2021年第1期9卷 284-290页

作者： Du-Han Kim Beom-Soo Kim Chul-hyun cho Department of Orthopedic Surgery Keimyung University Dongsan HospitalKeimyung University School of MedicineDaegu 42601South Korea

BACKGROUND Acromial and scapular spine fractures after reverse total shoulder arthroplasty(RTSA)are a well-known complication that may negatively impact the effects of long-term ***,to the best of our knowledge,there has been no report of simultaneous bilateral fractures of the acromion or scapular spine that occurred following staged *** SUMMARY A 79-year-old right-handed male visited our outpatient clinic with a chief complaint of pain and limited motion of both shoulder joints for a one-year *** on plain radiographs and magnetic resonance images,the preoperative diagnosis was bilateral cuff tear arthropathy with failed rotator cuff *** patient was treated with staged bilateral RTSA at a two-month *** 5 and 3 mo after right and left side surgery,the patient returned to the outpatient clinic with severe pain and limited motion of both shoulder joints for 2 wk without a traumatic event.A computed tomography scan revealed nondisplaced acromial base fractures of both *** bilateral involvement,fracture location,and patient’s demand,open reduction and internal fixation(ORIF)using plate for bilateral acromial base fractures were *** 2 years after ORIF,the fracture was completely healed,and the patient was satisfied with shoulder *** This report describes an extremely rare case of simultaneous bilateral acromial base fractures after staged RTSA managed successfully by ORIF with a precontoured plate designed for distal clavicle *** acromial fracture after RTSA can be treated conservatively,simultaneous bilateral fractures may warrant surgical intervention as a means of addressing difficulties in activities of daily living.

关键词： Acromion Fracture Arthroplasty Shoulder Reverse total shoulder arthroplasty Case report Complication

Role of two-dimensional shear wave elastography in chronic liver diseases: A narrative review

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 Gastroenterology 2018年第34期24卷 3849-3860页

作者： Jae Yoon Jeong Young Seo cho Joo hyun Sohn Department of Internal Medicine Hanyang University Guri Hospital Hanyang University College of Medicine Department of Radiology Hanyang University Guri Hospital Hanyang University College of Medicine

Liver biopsy is the gold standard for evaluating the degree of liver fibrosis in patients with chronic liver disease. However, due to the many limitations of liver biopsy, there has been much interest in the use of noninvasive techniques for this purpose. Among these techniques real-time two-dimensional shear wave elastography(2D-SWE) has the advantage of measuring tissue elasticity with the guidance of B-mode images. Recently, many studies have been conducted on the application of 2D-SWE in patients with various liver diseases, and their validity has been confirmed. Here, we briefly discuss the role of 2D-SWE in patients with chronic liver diseases, particularly aspects of the examination techniques and clinical applications.

关键词： Shear wave elastography Liver disease Liver fibrosis Portal hypertension Hepatocelluar carcinoma

Fruit Ripeness Prediction Based on DNN Feature Induction from Sparse Dataset

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第12期69卷 4003-4024页

作者： Wan hyun cho Sang Kyoon Kim Myung Hwan Na In Seop Na Department of Statistics Chonnam National UniversityGwangju61186Korea Department of Electronics Eng. Mokpo National UniversityMuan58557Korea National Program of Excellence in Software Centre Chosun UniversityGwangju61452Korea

Fruit processing devices,that automatically detect the freshness and ripening stages of fruits are very important in precision ***,based on deep learning,many attempts have been made in computer image processing,to monitor the ripening stage of ***,it is timeconsuming to acquire images of the various ripening stages to be used for training,and it is difficult to measure the ripening stages of fruits accurately with a small number of *** this paper,we propose a prediction system that can automatically determine the ripening stage of fruit by a combination of deep neural networks(DNNs)and machine learning(ML)that focus on optimizing them in combination on several image ***,we used eight DNN algorithms to extract the color feature vectors most suitable for classifying them from the observed images representing each ripening ***,we applied seven ML methods to determine the ripening stage of fruits based on the extracted color ***,we propose an automatic prediction system that can accurately determine the ripeness in images of various fruits such as strawberries and tomatoes by a combination of the DNN and ML ***,we used the transfer learning method to train the proposed system on few image datasets to increase the training ***,we experimented to find out which of the various combinations of DNN and ML methods demonstrated excellent classification *** the experimental results,a combination of DNNs and multilayer perceptron,or a combination of DNNs and support vector machine or kernel support vector machine generally exhibited excellent classification ***,the combination of various DNNs and statistical classification models shows that the overall classification rate is ***,in the case of using tomato images,it was found that the classification rate for the combination of various DNNs and ML methods was generally similar to the results obtained

关键词： Ripening stage prediction deep neural network machine learning tomato strawberry small dataset

Synthesis and characterization of Ba(Co_xNb_(1-x))O_3 nanoparticles by hydrothermal processing

在线全文

维普期刊数据库

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B9期19卷 92-95页

作者： hyun-Ju KIM Min-Cheol CHU Seong-Jai cho Dong-Sik BAE School of Nano & Advanced Materials Engineering Changwon National University Materials Evaluation Center Korea Research Institute of Standards and Science

The nanosized Ba(CoxNb1-x)O3(BCN) particles were prepared under high temperature and pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. Ba(CoxNb1-x)O3 powders were obtained in the temperature range of 170-210 ℃ for 6 h. The results show that the average size of the synthesized particles increases with increasing reaction temperature. The average size of the synthesized particles is about 10 nm. The crystalline phase of the synthesized particles is found to be Ba(CoxNb1-x)O3. Ceramics derived from the nano BCN powders could achieve high sintering density at a relatively low sintering temperature.

关键词：纳米粒子合成臭氧热加工表征平均粒径烧结温度氢氧化钾

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2011年第4期6卷 283-287页

作者： Sung Ho Jang Sang-hyun cho Mi Young Lee Yong hyun Kwon Min Cheul Chang Department of Physical Medicine and Rehabilitation College of MedicineYeungnam UniversityDaegu 705-717Republic of Korea Department of Physical Therapy Institute of Health ScienceYonsei University College of Health ScienceWounju-siGangwon-do 220-710Republic of Korea Department of Physical Therapy College of Health and TherapyDaegu Haany UniversitySuseongkuDaegu 706-060Republic of Korea Department of Physical Therapy Yeungnam College of Science and TechnologyNamkuDaegu 705-703Republic of Korea

The corticospinal tract （CST） is one of the most important neural tracts for motor function in the human brain. Little is known about age-related changes of the CST. tn this study, we tried to evaluate age-related changes of the CST using diffusion tensor imaging in 60 healthy subjects. The diffusion tensor imaging result revealed that the tract number and fractional anisotropy value were decreased, and the apparent diffusion coefficient （ADC） value was increased with aging. The distribution showed a semilog pattern for tract number, fractional anisotropy and ADC of the CST, and the pattern of each graph was near-linear. When compared with the diffusion tensor imaging parameters of subjects in the 20 s age group, tract number and fractional anisotropy values were significantly decreased in the 50 s-70 s age groups. Likewise, the ADC value was significantly higher in the 50 s-70 s age groups. The CST in the brain of normal subjects degenerated continuously from the 20 s to the 70 s, with a near-linear pattern, and degeneration of the CST began to manifest significantly in the subjects in their 50 s, compared with the subjects in their 20 s.

关键词： corticospinal tract motor function aging diffusion tensor imaging