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Synthesis, Structure and luminescent Property of a Zinc(Ⅱ) Coordination Polymer Incorporating Flexible Cyclohexane-1,2,3,4,5,6-hexacarboxylate ligand

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Chemical Research in Chinese Universities 2011年第3期27卷 354-357页

作者： WANg.jind.lIU Zhao-qing SU Ting-ting School of Chemistry and Chemical Engineering Guangzhou University Guangzhou 510006 P. R. China

The hydrothermal reaction of Zn（NO3）2·4H2O, cyclohexane-1,2,3,4,5,6-hexacarboxylic acid hydrate （H6lI·H2O, cis-conformation lI： a,e,a,e,a,e） and 2,2＇-bpy yielded a new coordination polymer [Zn2（H2lII）（2,2＇-bpy）]·2H2O（trans-conformation lII： e,e,e,e,e,e）, which was characterized by single-crystal X-ray diffraction, elemental analysis, IR and XRPD（X-ray powder diffraction）. This complex crystallized in the triclinic system, with P1 space group and parameters a=0.66922（5） nm, b=0.97291（8） nm, c=1.22184（9） nm, α=99.0020（10）°, β=99.1300（10）°, γ=99.1910（10）°, V= 0.76176（10） nm3 and Z=2. The structure is a three-dimensional supramolecular network based on linear coordination chains through π-π stacking and hydrogen bonding interactions. The confromation of the starting ligand H6lI transfromed to the H2lII. The complex emits strong luminescence at room temperature.

关键词： Coordination polymer Cyclohexane-1 2 3 4 5 6-hexacarboxylate Conformation luminescent property

Determination of the sensible heat effectiveness and pressure loss of a rotary regenerative heat exchanger using CFD

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Building Simulation 2023年第6期16卷 869-887页

作者： Vladimír Zmrhal Petr Zelenský jindřich Boháč Martin Barták Miroslav Kučera Roman Vavřička Faculty of Mechanical Engineering Department of Environmental EngineeringCzech Technical University in PragueTechnická416000Prague 6Czech Republic

The paper presents a new method to determine the sensible effectiveness and pressure loss of rotary regenerative heat exchangers using computational fluid dynamics(CFD).It is based on CFD simulations of a single thermal wheel microchannel with a small cross-sectional area and thin walls,with cyclic inlet and outlet boundary *** unique measurement set-ups were designed and built for the experimental measurement of the heat exchanger *** different types of thermal wheels were manufactured,measured,and simulated in ANSYS *** wheels achieve an effectiveness greater than 73%under certain(air flow)conditions,which is the minimum effectiveness required by Ecodesign(in the EU).For the examined exchangers,the effectiveness ranges from 66.5%to 83.3%,depending on the boundary conditions and geometric parameters of the *** highest sensible effectiveness is achieved by heat exchangers with the largest heat exchange surface Ac;on the other hand,these wheels have the largest pressure *** paper discusses the use of a simplifiedε-NTU correlation model for the HVAC systems(typically C*=1).The correlation model and CFD results were compared and found to be different from each *** results of the CFD simulation were compared with measurements to prove that the proposed simulation method can predict the behaviour of the real heat exchanger as a *** was demonstrated that the sensible effectiveness and pressure loss of the rotary heat exchanger predicted by the CFD simulations correspond well to the measured values within the measurement uncertainty±1.3%.The proposed method can be used for the comparison of different rotary regenerative heat exchangers before their manufacturing and for verification that they meet the EU Ecodesign requirements set by the current *** reduces the cost of the initial optimisation and testing of new designs.

关键词： rotary heat exchanger heat wheel microchannel heat recovery sensible effectiveness pressureloss computer fluid dynamics experiment

Near-Wall Flow in the Blade Cascades Representing last Rotor Root Sections of large Output Steam Turbines

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Journal of Thermal Science 2021年第1期30卷 220-230页

作者： ŠIMURDA David FÜRST Jiří HÁlA jindřich lUXA Martin BOBČÍK Marek NOVÁK Ondřej SYNÁČJaroslav Institute of Thermomechanics of the Czech Academy of Sciences Prague 18200Czech Republic Dpt.of Technical Mathematics Faculty of Mechanical EngineeringCTU in PraguePrague 12000Czech Republic Doosan Skoda Power Pilsen 30100Czech Republic

This paper investigates the flow past two variants of root section profile cascades for a last stage rotor considering three-dimensional flow structures in the near-wall *** were drawn based on RANS numerical simulations of both variants and on the experimental data obtained by the 3 D traversing in the exit flow field of one of the *** of 3 D structures at two different regimes and its influence on aerodynamic characteristics of the blade cascades was *** distributions of Mach number along the profiles were compared with 2 D optical measurements and its distortion due to the presence of the sidewall was *** interaction between main vortical structures was described and its influence on the loading of the blades,mechanical energy losses and exit flow angle was *** results showed that for a front loaded blade the vortical structures appeared earlier and at a larger extent than for an aft loaded ***,due to different Mach number distribution,contribution of end wall flow to the energy losses was lower in the case of the aft loaded *** influence of the near wall flow on the loading was found to be rather weak while the deviation of the exit flow angle appeared to be comparable for both of the variants.

关键词： turbine blade cascade secondary flow near wall flow supersonic flow CFD experiment

Medical implants by using RP and investment casting technologies

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China Foundry 2011年第1期8卷 107-111页

作者： Milan Horáek Ondej Charvát Tomá Pavelka Josef Sedlák Martin Madaj jindich Nejedl Jan Dvoáek Faculty of Mechanical Engineering Institute of Manufacturing Technology-Department of Foundry EngineeringBrno University of Technology

The paper deals with the production technology of knee joint replacement by using rapid prototyping *** aim of the work is to outline the manufacturing technology intended for prototype production with the use of rapid prototyping and investment casting technology for use in orthopaedics and the surgery of knee joint *** research results should make an effective contribution in the attempts to minimize the invasive surgical procedure,shorten the production of knee joint replacement as well as reduce the *** present,the research is focused on the preparation of STl data from CT (Computed Tomography) and verification of the production technology of prototypes made using available RP technology and its evaluation.

关键词： rapid prototyping investment casting knee joint replacement computed tomography

OSCIllATION　FREQUENCY　THEORY　OF　A　PIEZOElECTRIC　SENSOR　INlIQUID　PHASE　WITH　TWO　SEPARATED－ElECTRODES

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Chinese Chemical letters 1996年第2期7卷 169-172页

作者： Da Zhong SHEN Ze Chang lIU Qing KANg jind Tian HU(Chemistry College, Shandong University, Jinan, 250100)(Chemical Engineering Department, Jinan Branch of Shandong Institute of Mining and Technology, Jinan, 280031) Chemistry College Shandong University Jinan 250100 Chemical Engineering Department Jinan Branch Shandong Institute of Mining and Technology Jinan 250031

In this paper, an oscillation frequency equation for a pizoelectric sensor with two separated-electrodes is theoretically derived and experimentally verified. The correlatione of the oscillation frequency and the liqu... 详细信息

关键词： SENSOR FREQUENCY INlIQUID OF OSCIllATION PHASE PIEZOElECTRIC ElECTRODES SEPARATED THEORY

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双相不锈钢焊接热影响区的晶粒长大

长城技术 1993年第A期 263-274页

作者： jind.,ES 何益松

Enhancement of the ‘tractor-beam’ pulling force on an optically bound structure

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light(Science & Applications) 2017年第1期6卷 136-141页

作者： Jana Damková lukáš Chvátal Jan Ježek jindřich Oulehla Oto Brzobohatý Pavel Zemánek Institute of Scientific Instruments of the CAS v.v.i.Královopolská147Brno 61264Czech Republic

Recently,increasing attention has been devoted to mastering a new technique of optical delivery of micro-objects tractorbeam’1–*** beams have uniform intensity profiles along their propagation direction and can exert a negative force that,in contrast to the familiar pushing force associated with radiation pressure,pulls the scatterer toward the light *** was experimentally observed that under certain circumstances,the pulling force can be significantly enhanced6 if a non-spherical scatterer,for example,a linear chain of optically bound objects10–12,is optically *** we demonstrate that motion of two optically bound objects in a tractor beam strongly depends on theirs mutual distance and spatial *** configuration-dependent optical forces add extra flexibility to our ability to control matter with *** these interactions opens the door to new applications involving the formation,sorting or delivery of colloidal self-organized structures.

关键词： beam scatter mutual

Evaluation of natural forest regeneration as a part of land restoration in the Khentii massif,Mongolia

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Journal of Forestry Research 2020年第5期31卷 1773-1786页

作者： David Juricka Antonın Kusbach Jana Parılkova Jakub Houska Pavlına Ambrozova Vaclav Pecina Zdena Rosicka Martin Brtnicky jindrich Kynicky Department of geology and Pedology Faculty of Forestry and Wood TechnologyMendel UniversityZemedelska 161300 BrnoCzech Republic Department of Forest Botany Dendrology and GeobiocoenologyFaculty of Forestry and Wood TechnologyMendel UniversityZemedelska161300 BrnoCzech Republic Faculty of Civil Engineering Institute of Water StructuresBrno University of TechnologyZizkova 1760200 BrnoCzech Republic Central European Institute of Technology Brno University of TechnologyPurkynova 656/12361200 BrnoCzech Republic

Forest stands in the semi-arid environment of northern Mongolia have an essential role in controlling ongoing desertification in the surrounding *** the last decade,the total forest area has decreased *** aim of this study was to evaluate the potential of natural regeneration as an essential element for ensuring sustainability of these *** on field measurements from 120 plots in six sites,our assessment tool revealed five qualitative categories of forest regeneration,allowing us to assess impacts of both grazing and environmental conditions on the regeneration *** is a crucial factor and adversely affects *** sites with relatively low grazing intensity,low soil moisture levels represent the main reason for reduced *** approach to classification proposed in this study allows for the identification and interpretation of stand conditions where natural regeneration has *** study provides an important foundation to inform decisionmaking related to land protection and restoration *** findings could be used in comparative studies and,importantly,may aid further mapping of Mongolian forests.

关键词： Mongolia Natural forest regeneration Seedlings larix sibirica land restoration Desertification

large-scale permafrost degradation as a primary factor in larix sibirica forest dieback in the Khentii massif,northern Mongolia

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Journal of Forestry Research 2020年第1期31卷 197-208页

作者： David Juricka Jitka Novotna Jakub Houska Jana Parilkova Jan Hladky Vaclav Pecina Hana Cihlarova Marcela Burnog Jakub Elbl Zdena Rosicka Martin Brtnicky jindrich Kynicky Department of geology and Pedology Faculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 161300 BrnoCzech Republic Central European Institute of Technology Brno University of TechnologyPurkynova 656/12361200 BrnoCzech Republic Institute of Water Structures Faculty of Civil EngineeringBrno University of TechnologyZizkova 1760200 BrnoCzech Republic

The objective of this study is to investigate the potential causes of widespread larix sibirica *** observed in the Khentii massif of northern *** ratio of deadwood to living trees in affected stands in the goricho region,the southernmost study site situated close to the gobi Desert,was as high as 3.6:*** fluctuations monitored over 2 years using electrical impedance spectrometry revealed that the goricho study site had higher soil moisture levels than the two less affected sites Barun Bayan and Dzun *** soil moisture was recorded in an area characterized by highly skeletal soils,ones with more than 35%by volume of rock fragments,and comparatively shallow soil horizons,from valley to *** layer of permafrost influencing hydrogeological processes is much deeper in the goricho region compared to the undisturbed study *** analysis confirmed a significant number of dead *** on sites with developed *** forest stands,however damaged,grow in this region on well-drained scree slopes or on rocky *** mass mortality observed for *** may be directly linked to accelerated permafrost thaw in the area bordered by the Tuul and the Terelj *** assumption is that *** root system necrosis occurred as a result of long-term waterlogging of developed soils with high spatial heterogeneity,normally able to absorb high quantities of *** areas unaffected were scree fields and rocky bastions characterized by adequate *** of our findings support the primary stages of large-scale permafrost thaw,i.e.,correlating increases in soil moisture with increasing permafrost active layer thickness.

关键词： larix sibirica Mortality Permafrost thawing Waterlogging Mongolia