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Journal of Energy Chemistry 2019年第8期28卷 1-8,I0001页

作者： Yujin Sim Jihoon Yoo Jeong-myeong ha Ji Chul Jung Department of Chemical Engineering Myongji UniversityYongin 17058 Republic of Korea Clean Energy Research Center Korea Institute of Science and TechnologySeoul 02792 Republic of Korea

Oxidative coupling of methane(OCm) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H values on the catalytic activity of La AlO3 catalysts in this reaction. The results showed that the co-precipitation pH value affected greatly on the formation of chemical species of precipitate precursors in the co-precipitation step, leading to different phases of the finally obtained LaAlO3 *** the co-precipitation pH value increased up to 8, the lanthanum-related phases such as La2 O3 and La(OH)3 were gradually formed as by-products, preventing the formation of LaAlO3 perovskite crystalline structure and facilitating the formation of oxygen vacancies on catalyst surface. However, at pH value of9 or higher, the lanthanum content in the precipitate precursor was increased greatly. Not LaAlO3 perovskite but lanthanum-related phases were developed as main phases, reducing their catalytic activities in this reaction. Among LaAlO3 catalysts, the one prepared at pH = 8 showed the highest C2 yield due to its well-developed oxygen vacancies and electrophilic lattice oxygen. Therefore, the co-precipitation pH value strongly affected the LaAlO3 catalyst activity in OCm reaction. A precious pH control should be required to prepare various perovskite catalysts for the OCm.

关键词： LaAlO3 Perovskite Oxidative coupling of methane Co-precipitation pH value

Solid-state phase transformations toward a metal-organic framework of 7-connected Zn_(4)0 secondary building units

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Nano Research 2021年第2期14卷 411-416页

作者： Jaehui Kim Junsu ha Jae Hwa Lee Hoi Ri moon Department of Chemistry Ulsan National institute of Science and Technology(UNiST) Ulsan 44919Republic of Korea

in the development of metal-organic frameworks(mOFs),secondary building units(SBUs)have been utilized as molecular modules for the construction of nanoporous materials with robust *** solvothermal synthetic conditions,dynamic changes in the metal coordination environments and ligand coordination modes of SBUs determine the resultant product ***,mOF phases with new topologies can also be achieved by post-synthetic treatment of as-synthesized mOFs via the introduction of acidic or basic moieties that cause the simultaneous cleavage/reformation of coordination bonds in the solid *** this sense,we studied the solid-state transformation of two ndc-based Zn-mOFs(ndc=1,4-naphthalene dicarboxylate)with different SBUs but the same pcu topology to another mOF with sev *** of the chosen mOFs with pcu nets is[Zn_(2)(ndc)_(2)(bpy)]_(n)(bpy=4,4,-bipyridine),(6C_(bpy)-mOF)consisting of a 6-connected pillared-paddlewheel SBU,and the other is iRmOF-7 composed of 6-connected Zn40(C 00)6 SBUs and *** post-structural modification,these pcu mOFs were converted into the same mOF with sev topology constructed from the uncommon 7-connected Zri_(4)O(COO)_(7)SBU(7C-mOF).The appropriate post-synthetic conditions for the transformation of each SBUs were systematically *** addition,the effect of the pillar molecules in the pillared-paddlewheel mOFs on the topology conversion was studied in terms of the linker basicity,which determines the inertness during the solid-state phase *** post-synthetic modification approach is expected to expand the available methods for designing and synthesizing mOFs with controlled topologies.

关键词： metal-organic framework secondary building units solid-state transform ation linker basicity ligand addition reaction

COmPARiSON OF mAX-miN APPROACH AND NN mETHOD FOR RELiABiLiTY OPTimiZATiON OF SERiES-PARALLEL SYSTEm

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Systems Science and Systems Engineering 2003年第1期12卷 39-48页

作者： Hsiang LEE Way KUO Chunghun ha Department of industrial Engineering Texas A&M University College StationTX 77843-3131U.S.A.Department of Industrial EngineeringTexas A&M University College StationTX 77843-3131U.S.A.Department of Industrial EngineeringTexas A&M University College StationTX 77843-3131U.S.A.

Two heuristics, the max-min approach and the Nakagawa and Nakashima method, are considered for the redundancy allocation problem with series-parallel structure. The max-min approach can formulate the problem as an integer linear programming problem instead of an integer nonlinear problem. This paper presents a comparison between those methods from the standpoint of solution quality and computational complexity. The experimental results show that the max-min approach is superior to the Nakagawa and Nakashima method in terms of solution quality in small-scale problems, but analysis of computational complexity shows that the max-min approach is inferior to other greedy heuristics.

关键词： max-min approach heuristics redundancy allocation reliability optimization

Effects of Traditional Herbal Formulae on Human CYP450 isozymes

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Chinese Journal of integrative medicine 2017年第1期23卷 62-69页

作者： Seong Eun Jin Hyekyung ha Hyeun-Kyoo Shin K-Herb Research Center Korea Institute of Oriental MedicineDaejeon 34054Republic of Korea

Objective：To assess the effects of traditional herbal formulae Sijunzi Decoction（四君子汤,Sagunja-tang,SJZD）,Siwu Decoction（四物汤,Samul-tang,SWD）,Bawu Decoction（八物汤,Palmul-tang,BWD）and Shiquan Dabu Decoction（十全大补汤,Sipjeondaebo-tang,SDD）on the activities of human cytochrome P450（CYP450）,a drug-metabolizing ***：Herbal formula water extracts were filtered and lyophilized after the powder extracts were dissolved in distilled *** activities of major human CYP450isozymes（CYP3A4,CYP2C19,CYP2D6 and CYP2E1）were measured using in vitro fluorescence-based enzyme *** inhibitory effects of the herbal formulas on the activities of CYP450 were characterized as half maximal inhibition concentration（iC50）***：All the tested herbal formulae inhibited CYP2C19activity（iC50：SJZD,83.28μg/m L;SWD,235.54μg/m L;BWD,166.82μg/m L;SDD,178.19μg/m L）;SJZD（iC50=196.46μg/m L）,SWD（iC50=333.42μg/m L）and SDD（iC50=163.42μg/m L）inhibited CYP2E1-mediated metabolism;whereas BWD exhibited comparatively weak inhibition of CYP2E1（iC50=501.78μg/m L）.None of the four herbal formulas significantly affected CYP3A4 or ***：These results suggest that SJZD,SWD,BWD and SDD could potentially inhibit the metabolism of co-administered synthetic drugs whose primary route of elimination is via *** addition,clinically relevant pharmacokinetic interactions could occur when SJZD,SWD or SDD is co-administered with drugs metabolized by *** findings provide information for the safety and effective clinical use of these four classic herbal formulas.

关键词： cytochrome P450 Sijunzi Decoction Siwu decoction Bawu Decoction Shiquan Dabu Decoction,herb-drug interactions

Experimental investigation of Flexible hawkmoth-like Wings on the Wing-wake interaction in Hovering Flight

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Journal of Bionic Engineering 2018年第1期15卷 139-153页

作者： YeongGyun Ryu Jo Won Chang Joon Chung Dong-ha Kim Department of Aerospace Engineering Ryerson University Toronto Ontario M5B 2K3 Canada Department of Aeronautical Science and Flight Operation Korea Aerospace University 76 Hanggongdaehak-ro Deogyang-gu Goyang-si Gyeonggi-do 10540 Republic of Korea Aerodynamics Group Korean Air R&D Center Daejeon Metropolitan City 34054 Republic of Korea

To study wing-wake interaction for various wing flexibilities, force measurements and digital particle image velocimetry were carried out on flapping hawkmoth-like wings in a water tank. Wing thickness was employed as a design variable for the wing flexi- bility distributions. Abrupt flap-down and phase delay in flexible wings influenced the behaviors of the Leading-Edge Vortex （LEV） and Trailing-Edge Vortex （TEV）, generated by the previous stroke. While the rigid wing exhibited a detached LEV at the end of the stroke, wing with specific flexibilities obtained attached LEVs. The attached LEVs induced a relatively rapid flow toward the wing surface as a result of encountering the TEV, and the flow caused a higher lift peak. On the other hand, the wings with larger wing deformations generated distinctive changes in LEV and TEV behaviors. The flap-down helped the TEV form closer to the wing surface, and it thus caused a downwash rather than wing-wake interaction. Furthermore, the most flexible wing had a newly-formed pair of LEVs above the wing during the wing reversal, thereby being not able to generate the wing-wake interaction. These results help to understand the different vortex structures generated by flexible wings during the wing reversal and the corresponding effects of wing-wake interaction.

关键词： hovering flight flexible hawkmoth wings wing-wake interaction Digital Particle image Velocimetry (DPiV)

On the System Performance of mobile Edge Computing in an Uplink NOmA WSN With a multiantenna Access Point Over Nakagami-m Fading

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iEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 668-685页

作者： Van-Truong Truong Van Nhan Vo Dac-Binh ha Chakchai So-in the Faculty of Electrical-Electronic Engineering Duy Tan University the institute of Research and Development Duy Tan University the Faculty of information Technology Duy Tan University iEEE the Applied Network Technology(ANT)Laboratory Department of Computer ScienceCollege of ComputingKhon Kaen University

in this paper,we study the system performance of mobile edge computing(mEC)wireless sensor networks(WSNs)using a multiantenna access point(AP)and two sensor clusters based on uplink nonorthogonal multiple access(NOmA).Due to limited computation and energy resources,the cluster heads(CHs)offload their tasks to a multiantenna AP over Nakagami-m *** proposed a combination protocol for NOmA-mEC-WSNs in which the AP selects either selection combining(SC)or maximal ratio combining(mRC)and each cluster selects a CH to participate in the communication process by employing the sensor node(SN)*** derive the closed-form exact expressions of the successful computation probability(SCP)to evaluate the system performance with the latency and energy consumption constraints of the considered *** results are provided to gain insight into the system performance in terms of the SCP based on system parameters such as the number of AP antennas,number of SNs in each cluster,task length,working frequency,offloading ratio,and transmit power ***,to determine the optimal resource parameters,i.e.,the offloading ratio,power allocation of the two CHs,and mEC AP resources,we proposed two algorithms to achieve the best system *** approach reveals that the optimal parameters with different schemes significantly improve SCP compared to other similar *** use monte Carlo simulations to confirm the validity of our analysis.

关键词： mobile edge computing(mEC) Nakagami-m fading offloading selection combining(SC)/maximal ratio combining(mRC) successful computation probability(SCP) uplink nonortho-gonal multiple access(NOmA) wireless sensor networks(WSNs)

mesomorphic behavior of new azomethine liquid crystals having terminal iodo group

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Chinese Chemical Letters 2011年第3期22卷 260-263页

作者： Sie-Tiong ha Teck-Leong Lee Guan-Yeow Yeap masato m.ito Ayumu Saito masaaki Watanabe Department of Chemical Science Faculty of ScienceUniversiti Tunku Abdul RahmanJln UniversitiBandar Barat31900 KamparPerakMalaysia Liquid Crystal Research Laboratory School of Chemical SciencesUniversiti Sains Malaysia11800 MindenPenangMalaysia Faculty of Engineering Soka University1-236 Tangi-choHachiojiTokyo 192-8577Japan

A series of azomethine esters,3-hydroxy-4-{[（4-iodophenyl）imino]methyl}phenyl alkanoates possessing even number of carbon atoms at the terminal alkanoyloxy chain（C_（n-1）H_（2n-1）COO-,n = 4,6,8,10,12,14） was synthesized.n-Butanoyloxy was found non-mesogenic,whilst n-hexanoyloxy to n-tetradecanoyloxy exhibited enantiotropic smectic A phase with fan-shaped *** was found that the length of terminal alkanoyloxy chain influenced the mesomorphic properties.

关键词： Liquid crystals Azomethine ester Enantiotropic Smectic A

harmful effects of pyrethroid ester insecticide on the male reproductive system mainly through affecting testicular function and inflammatory markers

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BiOCELL 2020年第1期44卷 111-115页

作者： ha ABDEL mAKSOUD mk mAHFOUZ mi SOLimAN mohamed G ELhaRRiF m ABBASS ma EL-BADRY Department of Biochemistry Benha UniversityBenhaEgypt Department of Basic medical Sciences Shaqra UniversityShaqraaSaudi Arabia

Pyrethroid esters are widely used as insecticides worldwide. in this study, we aimed to evaluate the harmful effect of deltamethrin on the male reproductive system through the assessment of reproductive hormones, inflammatorymarkers, and testicular function. To achieve our aim, eighty male 7-9-week-old, Wistar rats were taken, weighed, and divided into four experimental groups. The first group was kept as a control group, and the other three groups were given deltamethrin orally at different concentrations (0.87, 8.7, and 17.4 mg/kg body weight) for nine weeks. The resultsindicated that deltamethrin administration associated with a significant decrease in reproductive hormones, especially FSH, LH, and significant elevation in the interleukin 2 (iL2), interleukin 6 (iL6), histamine, and cortisol levels. Also, thesignificance of inhibition of sperm motility and viability, decreased testis weights, sperm count, and fructose in semen were noted. These findings clarify the harmful effect of deltamethrin on the male reproductive system by producing a significant alteration in reproductive hormones, inflammatory markers as well as testicular function.

关键词： Deltamethrin Reproductive hormones inflammatory markers

Going only half the way:cell cycle exit after the G1 restriction point

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Signal Transduction and Targeted Therapy 2024年第1期9卷 1-2页

作者： Lisa muller Tony Gutschner mechthild hatzfeld Department of Pathobiochemistry Institute of Molecular MedicineMartin Luther University Halle-WittenbergCharles Tanford Protein Research CenterHalleGermany Department of RNA Biology and Pathogenesis Institute of Molecular MedicineMartin Luther University Halle-WittenbergCharles Tanford Protein Research CenterHalleGermany

in a recent article published in Nature,James *** et *** that cyclin A2 levels determine whether cells will make an entrance into mitosis or whether cells will leave the cell cycle after having passed the G1/restriction(R)-point implicating that the decision is fully reversible(Fig.1).This ground-breaking study could impact future approaches for cancer treatment by targeting the mitotic clock.

关键词： point cycle

Vertically aligned nanocomposite films by self-assembled epitaxial nucleation for super-broadband transparent conductors

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infomat 2023年第4期5卷 14-24页

作者： Youngkyoung ha Judith L.macmanus-Driscoll Shinbuhm Lee Department of Physics and Chemistry DGISTDaeguRepublic of Korea Department of Emerging materials Science DGISTDaeguRepublic of Korea Department of materials Science and metallurgy University of CambridgeCambridgeUK

Designing super-broadband transparent conductors is challenging because of the exclusive nature of conductivity and infrared ***,using a one-step process,we created vertically aligned nanocomposite conducting films with high transparency across a super-broad wavelength *** aligned transparent Ba_(3)V_(2)O_(8)nanocolumns with lateral-100-nm widths enable high transmittance(>50%,even at a 4-μm wavelength)for all incident light and outperform that of Sn-doped in_(2)O_(3),while the conducting SrVO_(3)matrix retains low resistivity(mΩcm at room temperature).A combined study of scanning transmission electron microscopy,scattering scanning nearfield infrared microscopy,and X-ray diffraction revealed that spontaneous phase separation of Ba_(3)V_(2)O_(8)nanocolumns in a SrVO_(3)matrix film occurs via self-assembled epitaxial *** vertically aligned nanocomposite films provide a fertile platform for next-generation optoelectronics.

关键词： epitaxial nucleation spontaneous phase separation SrVO_(3)-Ba_(3)V_(2)O_(8) super-broadband transparent conductors vertically aligned nanocomposite films