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Influence of dehydrating agents on the oxidative carbonylation of methanol for dimethyl carbonate synthesis over a Cu/Y-zeolite catalyst

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1059-1063页

作者： Dong-ho Lee Jiin You Je-Min Woo jung yoon Seo Young Cheol Park Jong-Seop Lee Hyunuk Kim Jong-ho Moon Seung Bin Park Greenhouse Gas Laboratory Korea Institute of Energy Research Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology Energy Material Laboratory Korea Institute of Energy Research

The influence of the dehydration by metal oxides on the synthesis of dimethyl carbonate （DMC） via oxidative carbonylation of methanol was studied. A Cu/Y-zeolite catalyst was prepared by the ion exchange method from CuCl2.2H2O and the commercial NH4-form of the Y type zeolite, The catalyst was characterized by X-ray fluorescence （XRF）, N2 adsorption （BET method）, X-ray diffraction （XRD）, and temperature-programmed de- sorption of ammonia （NH3-TPD） to evaluate its Cu and Cl content, surface area, structure, and acidity. Reaction tests were carried out using an autoclave （batch reactor） for 18 h at 403 K and 5.5 MPa （2CH3OH ＋ 1/2O2 ＋ CO （CH3O）2CO ＋ H2O）. The influence of various dehydrating agents （ZnO, MgO, and CaO） was examined with the aim of increasing the methanol conversion （XMeOH, MeOH conversion）. The MeOH conversion increased upon addition of metal oxides in the order CaO 〉〉 MgO 〉 ZnO, with the DMC selectivity （SDMC） following the order MgO 〉 CaO 〉 ZnO. The catalysts and dehydrating agents were characterized before and after the oxidative carbonylation of methanol by thermogravimetric and differential thermogravimetric （TG/DTG）, and XRD to con- firm that the dehydration reaction occurred via the metal oxide （MO ＋ H2O →M（OH）2）. The MeOH conversion increased from 8.7% to 14.6% and DMC selectivity increased from 39.0% to 53.1%, when using the dehydrating azent CaO.

关键词： Carbon monoxide Zeolite Catalyst Dimethyl carbonate Oxidative carbonylation Dehydrating agent

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Concept study of measuring gravitational constant using superconducting gravity gradiometer

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Chinese Physics B 2018年第8期27卷 130-135页

作者： Xing Bian ho jung Paik Martin Vol Moody University of Chinese Academy of Sciences Beijing 100049China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100190China Department of Physics University of MarylandCollege ParkMaryland 20742USA

Newton＇s gravitational constant G is the least known fundamental constant of nature. Since Cavendish made the first measurement of G with a torsion balance over two hundred years ago, the best results of G have been obtained by using torsion balances. however, the uncorrected anelasticity of torsion fibers makes the results questionable. We present a new method of G measurement by using a superconducting gravity gradiometer constructed with levitated test masses, which is free from the irregularities of mechanical suspension. The superconducting gravity gradiometer is rotated to generate a centrifugal acceleration that nulls the gravity field of the source mass, forming an artificial planetary system. This experiment has a potential accuracy of G better than 10 ppm.

关键词： gravitational constant superconducting gravity gradiometer artificial planetary system

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Formation Mechanism of Chunky Graphite and Its Preventive Measures

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Journal of Materials Science & Technology 2008年第3期24卷 289-295页

作者： Hideo Nakae Sanghoon jung ho-Chul Shin Department of Materials Science and Engineering Waseda University National Institute of AIST Corporate Res.and Dev.Div. Hyundai.Kia Motors

The formation mechanism of chunky graphite has been reviewed and studied. The study consisted of a unidirectional solidification method, a small droplet method and a furnace cooling method. Four kinds of iron samples were prepared, namely, the pure Fe-C, Fe-C-S, Fe-C-Ce and Fe-C-Si-Ce alloys, and three kinds of nickel samples, namely the Ni-C, Ni-C-S and Ni-C-Mg alloys. The results of the unidirectional solidification of the Ni-C alloys showed that spheroidal graphite is not observed in the continuous solidified region, in which only flake-like graphite is observed, while spheroidal graphite is usually observed in the quenched liquid region. The existence of spheroidal graphite in the solidified phase is recognized only in the discontinuous growth mode of the Ni-C-Mg alloy solidified at 150 mm/h. This means that the spheroidal graphite is directly crystallized from the melt and entrapped by the flake-like chunky graphite that is formed by the continuous growth mode. In the small droplet method, a small piece of the Fe-C or Fe-C-Ce sample was melted on a pure graphite plate then cooled at a different cooling rate in a He-3%H2 atmosphere. The graphite in the Fe-C-Ce alloy is usually spherical. Nevertheless, the graphite morphology of the final solidified area changed from spherical to chunky and chunky to ledeburite with an increase in the cooling rate. This means that the chunky graphite is formed in the residual liquid region by the solidification into Fe-graphite system. The sample was cooled in a furnace, and the graphite morphology changes from spherical to chunky and chunky to ledeburite with the decrease in the Si content. These phenomena can be confirmed by the cooling curves of these samples.

关键词： Chunky graphite Spheroidal graphite Solidification Cooling curve

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Fossil-Winged Fruits of Fraxinus(Oleaceae) and Liriodendron(Magnoliaceae) from the Duho Formation,Pohang Basin,Korea

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 845-852页

作者： Seung-ho jung Seong-Joo LEE Department of Geology Kyungpook National UniversityDaegu 702-701Korea

A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups： 15 specimens into a winged fruit of Fraxinus, and one specimen of Liriodendron. The most samaras （13 specimens） were identified as Fraxinus oishii, which is characterized by narrowly ovate or ovate-elliptic shapes that are 2.7-3.6 cm in length and 0.7-1 cm in width （i/w ratio=3.4-4）. The apexes of the Fraxinus oishii samara are round or slightly emarginated, and a seed of the samara is always located at the base, of which the general shape is narrow rhombic-ellipsoidal. The seed is 1.2-2 cm long and 0.5-0.7 cm wide. Two specimens are different from the samara of Fraxinus oishii. They have a 6.6 length/width ratio （3.3 cm long and 0.5 cm wide）, and thus, are temporarily classified into the Fraxinus sp. One specimen was recognized as a winged seed of Liriodendron meisenense. The wing is broadly lanceolate to elliptic in shape, has a smooth, acute apex, and is approximately 3 cm long and 0.7 cm wide. Samaras of Fraxinus oishii and Liriodendron meisenense were early reported from the Middle Miocene deposits from North Korea, but these specimens are the first discovery in South Korea. Further study of the Duho Formation may connect flora relationships between North and South Korea.

关键词： winged fruits Fraxinus Liriodendron Middle Miocene Pohang Basin Korea

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Introduction to the Special Issue on“Innovation and Application of Intelligent Processing of Data,Information and Knowledge in E-Commerce”

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Computer Modeling in Engineering & Sciences 2022年第4期131卷 19-21页

作者： honghao Gao jung yoon Kim Yuyu Yin School of Computer Engineering and Science Shanghai UniversityShanghaiChina Department of Game Media College of Future IndustryGachon UniversitySeongnam-si13120Gyeonggi-doSouth Korea School of Computer Hangzhou Dianzi UniversityHangzhouChina

In the context of E-Commerce eco-system,there are hundreds of millions of consumers,thousands of businesses and shops,and hundreds of delivery *** E-Commerce businesses such as Alibaba Group need to support a large number of applications and business modules,and cater for hundreds of business requirements and independent changes on a daily *** intersection of these information technologies and business models provides ample research opportunities in intelligent processing of data,information and *** this special issue,we have accepted 7 papers from open calls and invitations.A summary of these papers is outlined below.

关键词： hundreds intersection invitation

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Energy efficient mechanism using flexible medium access control protocol for hybrid wireless sensor networks

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Journal of Central South University 2013年第8期20卷 2165-2174页

作者： SUN Ning JEONG yoon-su LEE Sang-ho Department of Computer Science Chungbuk National University Department of Information Communication Engineering Mokwon University

Energy efficiency is a primary consideration in a wireless sensor network (WSN). This is also a major parameter when designing a medium access control (MAC) protocol for WSNs. Hierarchical clustering structure is regarded suitable for WSNs due to its good performance in energy conservation. In this work, an adequately flexible mechanism for clustering WSNs is designed, in which some creative or promotional metrics are utilized, such as cluster head selection algorithm, cluster optional reconstruction, interested data transmission, multiple path routing protocol. All these strategies were cooperated to maximize energy saving of whole system. An appropriate MAC protocol for this mechanism is proposed, by flexibly switching the status of diverse sensor nodes in different strategies. The simulation results show that the proposed MAC protocol is suitable for clustering WSNs and performs well in aspects of energy efficiency, flexibility and scalability.

关键词： MAC protocol energy conservation flexibility re-clustering wireless sensor network

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Development of practical postprocessor for 5-axis machine tool with non-orthogonal rotary axes

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Journal of Central South University 2011年第1期18卷 159-164页

作者： jung Hyoun-Chul HWANG Jong-Dae PARK Ki-Beom jung yoon-Gyo School of Mechatronics Changwon National University

In order to develop a practical postprocessor for 5-axis machine tool,the general equations of numerically controlled(NC) data for 5-axis configurations with non-orthogonal rotary axes were exactly expressed by the inverse kinematics,and a windows-based postprocessor written with Visual Basic was developed according to the proposed *** developed postprocessor is a general system suitable for all kinds of 5-axis machines with orthogonal and non-orthogonal rotary *** implementation of the developed postprocessor and verification by a cutting simulation and machining experiment,the effectiveness of the proposed algorithm is *** is improved by allowing exchange of data formats such as rotational total center position(RTCP) controlled NC data,vector post NC data,and program object file(POF) cutter location(CL) data,and convenience is increased by adding the function of work-piece origin ***,a practical post-processor for 5-axis machining is developed.

关键词： post-processor 5-axis machining non-orthogonal rotary axes numerically controlled (NC) data CL data

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Continuity control method of cutter posture vector for efficient five-axis machining

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Journal of Central South University 2011年第6期18卷 1969-1975页

作者： HWANG Jong-dae KIM Sang-myung jung Hyun-chul jung yoon-gyo School of Mechatronics Changwon National University

During five-axis machining of impeller, the excessive local interference avoidance leads to inconsistency of cutter posture, low quality of machined surface and increase of processing time. Therefore, in order to improve the efficiency of five-axis machining of impellers, it is necessary to minimize the cutter posture changes and create a continuous tool path while avoiding interference. By using an MC-space algorithm for interference avoidance, an MB-spline algorithm for continuous control was intended to create a five-axis machining tool path with excellent surface quality and economic feasibility. A five-axis cutting experiment was performed to verify the effectiveness of the continuity control. The result shows that the surface shape with continuous method is greatly improved, and the surface roughness is generally favorable. Consequently, the effectiveness of the suggested method is verified by identifying the improvement of efficiency of five-axis machining of an impeller in aspects of surface quality and machining time.

关键词： five-axis control machining configuration-space B-spline continuity control method impeller interference

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Hwangryunhaedoktang exerts anti-inflammation on LPS-induced NO production by suppressing MAPK and NF-κB activation in RAW264.7 macrophages

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Journal of Integrative Medicine 2017年第4期15卷 326-336页

作者： Byung Hyuk Han Yun jung Lee jung Joo yoon Eun Sik Choi Seung Namgung Xian Jun Jin Da Hye Jeong Dae Gill Kang ho Sub Lee College of Oriental Medicine and Professional Graduate School of Oriental Medicine Wonkwang University Hanbang Body-fluid Research Center Wonkwang University

OBJECTIVE： This study aimed to evaluate whether Hwangryunhaedoktang （HHT）, a herbal compound, has an inhibitory effect on lipopolysaccharide （LPS）-induced inflammation in RAW264.7 macrophages. METhoDS： The effects of HHT were evaluated by confirming nitric oxide （NO） production and expression of inducible NO synthase （iNOS） and mitogen-activated protein kinases （MAPKs） in LPS-stimulated RAW264.7 macrophages via the Griess assay, Western blotting, and real-time reverse transcription quantitative polymerase chain reaction. Western blot analyses and luciferase assays were used to evaluate whether HHT has an effect on the phosphorylation and translocation of nuclear factor-κB （NF-κB）. The secretion and expression of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） were determined via enzyme-linked immunosorbent assay and Western blot analyses. RESULTS： HHT suppressed LPS-induced NO production and expression of iNOS in a dose-dependent manner. Additionally, MAPKs activation was also attenuated via inhibition of phosphorylation of extracellular signal-regulated kinases 1/2, c-Jun N-terminal kinase and p38 which were related to inflammatory pathway. Furthermore, HHT also effectively attenuated NF-κB activation and its translocation to the nucleus, a process that is closely linked to inflammation. LPS normally induced the expression of inflammatory cytokines such as TNF-α and IL-6, but the secretion and expression of TNF-α and IL-6 were significantly attenuated by pretreating the cells with HHT. CONCLUSION： HHT suppressed LPS-induced NO production by blocking the activation of NF-κB and MAPK signaling pathways in RAW264.7 macrophages. Furthermore, HHT may have an anti-inflammatory effect by suppressing the LPS-induced secretion of TNF-α and IL-6. Therefore, the traditional herbal formula HHT might be a useful potential therapeutic agent for inflammation.

关键词： medicine, Chinese traditional lipopolysaccharide nitric oxide nuclear factor-κB mitogen-activatedprotein kinases tumor necrosis factor-a inflammation

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Involvement of heme oxygenase-1 induction in anti-vascular inflammation effects of Xanthoceras sorbifolia in human umbilical vein endothelial cells

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Journal of Traditional Chinese Medicine 2018年第6期38卷 803-814页

作者： jung Joo yoon Byung Hyuk Han Eun Sik Choi Seung Namgung Da Hye Jeong Song Nan Jin Yun jung Lee Dae Gill Kang ho Sub Lee College of Oriental Medicine and Professional Graduate School of Oriental Medicine Wonkwang University Hanbang Cardio-Renal Syndrome Research Center Wonkwang University Institute of Materia Medica Taishan Medical University

OBJECTIVE: To define the effects of Xanthoceras sorbifolia(EXS) on vascular inflammation and the mechanisms in endothelial ***: Vascular protective effects of an ethanol extract of seeds from EXS(1-50 μg/mL) against tumor necrosis factor-α(TNF-α)-induced vascularinflammation were examined in human umbilical vein endothelial cells(HUVECs).RESULTS: EXS significantly decreased TNF-α-induced expression of cell adhesion molecules, such as intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and endothelial cell selectin,in a dose-dependent manner. Pre-treatment with EXS significantly inhibited translocation and transcriptional activity of nuclear factor-κB(NF-κB) increased by TNF-α. EXS also significantly inhibited formation of intracellular reactive oxygen species(ROS). Moreover, the vascular protective effects of EXS were linked to up-regulation of heme oxygenase-1(ho-1) and nuclear factor E2-related factor-2(Nrf-2) expression. EXS-induced ho-1 expression was significantly decreased in SnPP(ho-1 inhibitor)-and ho-1 siRNA-treated cells, whereas an increase was found in cobalt protoporphyrin IX(CoPP)(ho-1 inducer)-treated cells. In addition, pretreatment with EXS increased ho-1 and Nrf-2 expression under TNF-α stimulation with or without N-acetyl-L-cysteine. Furthermore, the inhibitory effects of EXS on TNF-α-induced vascular inflammation were partially reversed in SnPP-and of ho-1siRNA-treated cells but increased by ***: These results suggest that EXS may have important implications for prevention of vascular complications associated with vascular inflammation by inhibition of the NF-κB/ROS pathway and activation of the Nrf-2/ho-1 pathway.

关键词： Sapindaceae Vascular disease inflammation Human umbilical vein endothelial cells Cell adhesion molecules NF-kappa B Heme oxy-genase-1

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