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Single-atom Pd catalyst anchored on Zr-based metal-organic polyhedra for Suzuki-Miyaura cross coupling reactions in aqueous media

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Nano Research 2021年第2期14卷 486-492页

作者： Seongsoo Kim Seohyeon Jee kyung Min Choi Dong-sik shin Division of Chemical and Bioengineering Kangwon National UniversityGangwon-do 24341Republic of Korea Department of Chemical and Biological Engineering Sookmyung Womens University100 Cheongpa-ro 47-gilYongsan-guSeoul 04310Republic of Korea

The challenge for single-atom catalysts in various C-C cross coupling reaction exists in the development of solid supporting *** has been desired tofind a supporting material designed in molecular level to anchor a single-atom catalyst and provide high degree of dispersion and substrate access in aqueous ***,we prepared discrete cages of metal-organic polyhedra anchoring single Pd atom(MOP-BPY(Pd))and successfully performed a Suzuki-Miyaura cross coupling reaction with various substrates in aqueous *** was revealed that each tetrahedral cage of MOP-BPY(Pd)has 4.5 Pd atoms on average and retained its high degree of dispersion up to 3 months in *** coupling efficiencies of the Suzuki-Miyaura cross coupling reaction exhibited more than 90.0%for various substrates we have tested in the aqueous media,which is superior to those of the molecular Pd complex and metal-organic framework(MOF)anchoring Pd ***,MOP-BPY(Pd)was successfully recovered and recycled without performance degradation.

关键词： metal-organic polyhedra Suzuki-Miyaura cross coupling reaction structure characterization aqueous phase reaction high-degree of dispersion

Efects on nano zero-valent iron reactivity of interactions between hardness, alkalinity, and natural organic matter in reverse osmosis concentrate

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Journal of Environmental Sciences 2013年第11期25卷 2177-2184页

作者： Yuhoon Hwang Hang-sik shin Department of Environmental Engineering Technical University of Denmark Department of Civil and Environmental Engineering Korea Advanced Institute of Science and Technology

Nanoscale zero-valent iron （NZVI） is considered to have potential to reduce nitrate in the concentrate generated by high pressure membrane processes aimed at water reuse. However, it is necessary to verify the effect of the matrix components in the concentrates on NZVI reactivity. In this study, the influence of hardness, alkalinity, and organic matter on NZVI reactivity was evaluated by the response surface method （RSM）. Hardness （Ca/＋） had a positive effect on NZVI reactivity by accelerating iron corrosion. In contrast, alkalinity （bicarbonate; HCO3） and organic matter （humic acid; HA） had negative effects on NZVI reactivity due to morphological change to carbonate green rust, and to competitive adsorption of HA, respectively. The validity of the statistical prediction model derived from RSM was confirmed by an additional confirmation experiment, and the experimental result was within the 95% confidential interval. Therefore, it can be indicated that the RSM model produced results that were statistically significant.

关键词： nitrate reduction concentrate treatment response surface method nano zero valent iron

Degenerate s-Extended Complete and Incomplete Lah-Bell Polynomials

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Computer Modeling in Engineering & Sciences 2022年第6期130卷 1479-1495页

作者： Hye kyung Kim Dae sik Lee Department of Mathematics Education Daegu Catholic UniversityGyeongsan38430Korea School of Electronic and Electric Engineering Daegu UniversityGyeongsan38453Korea

Degenerate versions of special polynomials and numbers applied to social problems,physics,and applied mathematics have been studied variously in recent ***,the(s-)Lah numbers have many other interesting applications in analysis and *** this paper,we divide two *** first introduce new types of both degenerate incomplete and complete s-Bell polynomials respectively and investigate some properties of them ***,we introduce the degenerate versions of complete and incomplete Lah-Bell polynomials as multivariate forms for a new type of degenerate s-extended Lah-Bell polynomials and numbers *** investigate relations between these polynomials and degenerate incomplete and complete s-Bell polynomials,and derive explicit formulas for these polynomials.

关键词： Lah-Bell numbers and polynomials s-extended Lah-Bell numbers and polynomials complete s-Bell polynomials incomplete s-Bell polynomials s-Stirling numbers of second kind

Some Properties of Degenerate r-Dowling Polynomials and Numbers of the Second Kind

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 825-842页

作者： Hye kyung Kim Dae sik Lee Department of Mathematics Education Daegu Catholic UniversityGyeongsan38430Korea School of Electronic and Electric Engineering Daegu UniversityGyeongsan38453Korea

The generating functions of special numbers and polynomials have various applications in many fields as well as mathematics and *** recent years,some mathematicians have studied degenerate version of them and obtained many interesting *** this in mind,in this paper,we introduce the degenerate r-Dowling polynomials and numbers associated with the degenerate r-Whitney numbers of the second *** derive many interesting properties and identities for them including generating functions,Dobinski-like formula,integral representations,recurrence relations,differential equation and various explicit *** addition,we explore some expressions for them that can be derived from repeated applications of certain operators to the exponential functions,the derivatives of them and some identities involving them.

关键词： Dowling lattice Whitney numbers and polynomials r-Whitney numbers and polynomials of the second kind r-Bell polynomials r-Stirling numbers dowling numbers and polynomials

Effects of Melandrium firmum methanolic extract on testosterone-induced benign prostatic hyperplasia in Wistar rats

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Asian Journal of Andrology 2012年第2期14卷 320-324页

作者： Mee-Young Lee In-sik shin Chang-Seob Seo Nam-Hun Lee Hye-kyung Ha Jong-Keun Son Hyeun-Kyoo shin Herbal Medicine EBM Research Center Korea institute of Oriental MedicineExporo 483Yusung-guDaejeon 305-811Koreaand Coilege of Pharmacy Yeungnam UniversityGyonsan 712-749Korea

Benign prostatic hyperplasia （BPH） is an age-related disease of unknown aetiology characterized by prostatic enlargement coincident with distinct alterations in tissue histomorphology. Instead of therapeutic agents that can cause severe side effects, plant extracts are frequently used to treat BPH. In this study, we investigated whether the Melandrium firmum methanolic extract （MFME） improves BPH, using the testosterone propionate （TP）-induced BPH rat model. Castration was performed via the scrotal route under sodium pentobarbital anaesthesia. BPH in castrated rats was generated via daily subcutaneous injections of TP （3 mg kg-1） dissolved in corn oil, for 4 weeks. MFME was administered daily by oral garage at a dose of 200 mg kg-1 for 4 weeks, along with the TP injections. The control group received injections of corn oil subcutaneously. At the scheduled termination of the experiment, all rats were killed and their prostates weighed; the relative prostate weight （prostate/body weight ratio） was calculated, and histomorphological changes in the prostate were examined. Additionally, we measured the levels of testosterone and dihydrotestosterone （DHT） in the serum and the prostate. Experimentally induced BPH led to marked decreases in the relative prostate weight and the DHT levels in the serum and the prostate. Histologically, BPH was evident in the ventral lobe of the prostate, and MFME treatment suppressed the severity of the lesions. These results indicate that MFME effectively inhibits the development of BPH induced by testosterone in a rat model. Further studies will be needed to identify the compound（s） responsibility for inducing the protective effect against BPH and determine its mechanism of action,

关键词： benign prostatic hyperplasia dihydrotestosterone Melandrium firmum (S. et Z.)RoHRB prostate testosterone

Irritable bowel syndrome:Emerging paradigm in pathophysiology

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World Journal of Gastroenterology 2014年第10期20卷 2456-2469页

作者： Yoo Jin Lee kyung sik Park Division of Gastroenterology and Hepatology Department of Internal Medicine Keimyung University School of Medicine Daegu 700-712 South Korea

Irritable bowel syndrome(IBS)is one of the most common gastrointestinal disorders,characterized by abdominal pain,bloating,and changes in bowel *** symptoms cannot be explained by structural abnormalities and there is no specific laboratory test or biomarker for ***,IBS is classified as a functional disorder with diagnosis dependent on the history taking about manifested symptoms and careful physical *** a great deal of research has been carried out in this area,the pathophysiology of IBS is complex and not completely *** factors are thought to contribute to the symptoms in IBS patients;altered gastrointestinal motility,visceral hypersensitivity,and the brain-gut interaction are important classical concepts in IBS *** areas of research in this arena include inflammation,postinfectious low-grade inflammation,genetic and immunologic factors,an altered microbiota,dietary factors,and enteroendocrine *** emerging studies have not shown consistent results,provoking controversy in the IBS ***,certain lines of evidence suggest that these mechanisms are important at least a subset of IBS patients,confirming that IBS symptoms cannot be explained by a single etiological ***,it is important to keep in mind that IBS requires a more holistic approach to determining effective treatment and understanding the underlying mechanisms.

关键词： Pathophysiology Irritable bowel syndrome Inflammation Immunologic Genetics Microbiota Diet Enteroendocrine cell

Tensor based non-photo realistic rendering for Korean architectural images

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Journal of Central South University 2014年第10期21卷 3805-3810页

作者： Do kyung shin Eun Young Ahn Deprtment of Computer Science and Engineering Hanyang University Deprtment of Communication Infromation & Computer Engineering Hanbat National University

Existing pen and ink sketch technologies can be applied to general images, but they could not produce optimal output for images of traditional architecture, because most images consist of exquisite straight lined patterns in traditional architecture, such as root tiles and window bars. The lines of roofs and eaves need to be described delicately to express pen and ink sketch most effectively. Therefore, by proposing a method to create white noise for light and shade of input images, to extract input vector directions from the white noise, and to determine the direction and length of stroke, a new expression technique is proposed for pen and ink sketch that could best reflect the characteristics of traditional architecture.

关键词： non-photo realistic rendering pen and ink sketch tensor

Implementation of Turbulent Mixing over a Stratocumulus-Topped Boundary Layer and Its Impact in a GCM

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Advances in Atmospheric Sciences 2009年第5期26卷 995-1004页

作者： Sun-Hee shin kyung-Ja HA Division of Earth Environmental System Pusan National University

The effect of a vertical diffusion scheme over a stratocumulus topped boundary layer （STBL） was investigated using the YONU AGCM （Yonsei University Atmospheric General Circulation Model）. To consider the impact of clouds on the turbulence production, the turbulence mixing term, driven by radiative cooling at the cloud top, is implemented as an extended non-local diffusion scheme. In the model with this new scheme, the STBL parameterization significantly influences the lower atmosphere over the tropical and subtropical regions. Consideration of the turbulent mixing within the cloud layer leads to continuous stratocumulus formation. The cloud-top radiative cooling tends to favor more rapid entrainment and produces top-down turbulent mixing. This cooling develops a mixed layer without initiation of deep convection by surface fluxes. Variations in thermodynamical and dynamical features are produced by planetary boundary layer （PBL） cloud development. The simulated stratocumulus induces more mixing of heat and moisture due to the cloud forcing. Over STBL regions, the lower boundary layer becomes warmer and drier. It also weakens vertical motion and zonal trade winds in the eastern Pacific, which indicates that stratocumulus cloud cover plays a role in weakening the Walker circulation; that is, cloud cover damps the tropical circulation.

关键词： stratocumulus topped boundary layer non-local diffusion scheme tropical circulation general circulation model

Modeling asymmetric fracture mechanics of Mg alloy wire in drawing process

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Journal of Magnesium and Alloys 2024年第5期12卷 2057-2069页

作者： Sunghoon Choi Jongwon shin Joung sik Suh Dongchoul Kim Department of Mechanical Engineering Sogang UniversitySeoul04107Republic of Korea Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea

In this study,a numerical analysis was conducted on the ductile fracture of a 2-mm diameter Mg-1Zn-0.5Mn-0.5Sr-0.1Ca alloy wire during *** hexagonally close-packed crystal structure of Mg alloys causes asymmetric fracture behavior,especially in the compression *** aim of this study is to develop a comprehensive damage model for Mg alloy wire that accurately predicts ductile fracture,with a focus on the compression region.A novel experimental method was introduced to measure the ductile fracture of Mg alloy wires under different stress *** wire drawing process was simulated using the Generalized Incremental Stress-State dependent damage(GISSMO)Model and the Semi-Analytical Model for Polymers(SAMP)*** damage model's prediction and the experimental results were found to be in excellent agreement,especially in determining crack *** analysis established a safe zone diagram for die angle and reduction ratio,and experimental validation confirmed the feasibility of this *** proposed damage model can provide a practical and reliable analysis for optimizing the drawing process of Mg alloy wire.

关键词： Mg alloy Wire drawing Finite element method Damage model Safe zone diagram