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GLYX-13 pretreatment ameliorates long-term isoflurane exposure-induced cognitive impairment in mice 预览
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作者 Huan Liu Xiang-Dan Gong +3 位作者 Xin Zhao Yue Qian Xiao-Ping Gu Tian-Jiao Xia 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第1期128-135,共8页
Accumulating evidence indicates that inhalation anesthetics induce or increase the risk of cognitive impairment.GLYX-13(rapastinel)acts on the glycine site of N-methyl-D-aspartate receptors(NMDARs)and has been shown t... Accumulating evidence indicates that inhalation anesthetics induce or increase the risk of cognitive impairment.GLYX-13(rapastinel)acts on the glycine site of N-methyl-D-aspartate receptors(NMDARs)and has been shown to enhance hippocampus-dependent learning and memory function.However,the mechanisms by which GLYX-13 affects learning and memory function are still unclear.In this study,we investigated these mechanisms in a mouse model of long-term anesthesia exposure.Mice were intravenously administered 1 mg/kg GLYX-13 at 2 hours before isoflurane exposure(1.5%for 6 hours).Cognitive function was assessed using the contextual fear conditioning test and the novel object recognition test.The mRNA expression and phosphorylated protein levels of NMDAR pathway components,N-methyl-D-aspartate receptor subunit 2B(NR2B)-Ca^2+/calmodulin dependent protein kinaseⅡ(CaMKII)-cyclic adenosine monophosphate response element binding protein(CREB),in the hippocampus were evaluated by quantitative RT-PCR and western blot assay.Pretreatment with GLYX-13 ameliorated isoflurane exposure-induced cognitive impairment and restored NR2B,CaMKII and CREB mRNA and phosphorylated protein levels.Intracerebroventricular injection of KN93,a selective CaMKII inhibitor,significantly diminished the effect of GLYX-13 on cognitive function and NR2B,CaMKII and CREB levels in the hippocampus.Taken together,our findings suggest that GLYX-13 pretreatment alleviates isoflurane-induced cognitive dysfunction by protecting against perturbation of the NR2B/CaMKII/CREB signaling pathway in the hippocampus.Therefore,GLYX-13 may have therapeutic potential for the treatment of anesthesia-induced cognitive dysfunction.This study was approved by the Experimental Animal Ethics Committee of Drum Tower Hospital affiliated to the Medical College of Nanjing University,China(approval No.20171102)on November 20,2017. 展开更多
关键词 Ca^2+/calmodulin-dependent PROTEIN kinaseⅡ cognitive impairment contextual FEAR conditioning cyclic adenosine MONOPHOSPHATE response element binding PROTEIN GLYX-13 ISOFLURANE N-METHYL-D-ASPARTATE receptor novel object recognition rapastinel
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Effect of heat treatment on cyclic deformation properties of Fe-26Mn-10AI-C steel
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作者 He Li Jian-ping Zhao +1 位作者 Zhan-yu Wang Li Ding 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第2期200-210,共11页
Fully reversed tensile-compression low-cycle fatigue tests were performed at room temperature under strain amplitude of 0.4%.The monotonic tensile results show that Fe-26Mn-10A1-C steels are fully austenite and(he opt... Fully reversed tensile-compression low-cycle fatigue tests were performed at room temperature under strain amplitude of 0.4%.The monotonic tensile results show that Fe-26Mn-10A1-C steels are fully austenite and(he optimal combination of ultimate tensile strength and total elongation was present at 950°C with 65 GPa%.The fatigue results show that the specimen at 1050°C has the maximum fatigue life of 162,000 cycles,which is much longer than twinning-induced plasticity(TWIP)steels of the same strain amplitude.The hot-forging specimen shows high similarity with TWIP steels with rapid initial cyclic hardening followed by cyclic softening and cyclic saturation.After solution heat treatment,it is noteworthy that,after rapid initial cyclic softening,another rapid cyclic hardening and a following decrease with fluctuation were observed at 1000°C.It is reas on able to believe that it is caused by K-carbides precipitated during cyclic deformation.Anolher interesting phenomenon is cyclic stress subsidence observed at 1050°C during its saturation stage at the last quarter of the fatigue life,and the span is about 12.5%of whole fatigue life. 展开更多
关键词 Fe-Mn-AI-C STEEL Low-cycle fatigue CYCLIC hardening CYCLIC SOFTENING CYCLIC stress SUBSIDENCE
A Stepwise Annulation for the Transformation of Cyclic Ketones to Fused 6 and 7-Membered Cyclic Enimines and Enones
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作者 Dong-Ping Wu Qian He +2 位作者 Dong-Huang Chen Jian-Liang Ye Pei-Qiang Huang 《中国化学:英文版》 SCIE CAS CSCD 2019年第4期315-322,I0002共9页
The efficient construction of functionalized polycyclic structures is an imports nt objective in organic synthesis.Herein,we disclose a three-step"[2+n]"annulation method for the transformation of cyclic ket... The efficient construction of functionalized polycyclic structures is an imports nt objective in organic synthesis.Herein,we disclose a three-step"[2+n]"annulation method for the transformation of cyclic ketones to fused enimines and enones.The method relies on the Suzuki coupling reaction and the amide reductive alkenylation reaction.A series of fused bicyclic(6/6,6/7,8/7)and tricyclic(6/6/6;6/6/7,6/5/7)ring systems bearing an α,β-enimine or an α,β-enone functionality have been synthetized in good overall yields. 展开更多
关键词 CYCLIC KETONES FUSED 6 and 7-Membered CYCLIC Enimines and ENONES functionalized POLYCYCLIC structures
Effi ciency of employing fi ber-based fi nite-length plastic hinges in simulating the cyclic and seismic behavior of steel hollow columns compared with other common modelling approaches 预览
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作者 Mojtaba Farahi Saeed Erfani 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第4期777-794,共18页
The accuracy and effi ciency of the modelling techniques utilized to model the nonlinear behavior of structural components is a signifi cant issue in earthquake engineering. In this study, the suffi ciency of three di... The accuracy and effi ciency of the modelling techniques utilized to model the nonlinear behavior of structural components is a signifi cant issue in earthquake engineering. In this study, the suffi ciency of three diff erent modelling techniques that can be employed to simulate the structural behavior of columns is investigated. A fi ber-based fi nite length plastic hinge (FB-FLPH) model is calibrated in this study. In order to calibrate the FB-FLPH model, a novel database of the cyclic behavior of hollow steel columns under simultaneous axial and lateral loading cycles with varying amplitudes is used. By employing the FB-FLPH model calibrated in this study, the interaction of the axial force and the bending moment in columns is directly taken into account, and the deterioration in the cyclic behavior of these members is implicitly considered. The superiority of the calibrated FB-FLPH modelling approach is examined compared with the cases in which conventional fi ber-based distributed plasticity and concentrated plasticity models are utilized. The effi ciency of the enumerated modelling techniques is probed when they are implemented to model the columns of a typical special moment frame in order to prove the advantage of the FB-FLPH modelling approach. 展开更多
关键词 CYCLIC behavior seismic behavior FI ber-based FI nite-length plastic hinge model FI ber-based modelling techniques CYCLIC strength deterioration axial force-bending moment interaction
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受压弯剪型开孔芯材屈曲约束支撑试验 预览
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作者 贾良玖 董洋 《湖南大学学报:自然科学版》 EI CAS CSCD 北大核心 2019年第3期66-73,共8页
提出一种芯材开孔的新型全钢屈曲约束支撑,简称为PBRB.该支撑由开孔平板芯材,填充板及盖板通过螺栓连接而成.通过3根芯材具有不同开孔形式的PBRB试件的拟静力试验和相关数值分析,重点考察了芯材开孔形式对PBRB抗震性能的影响.研究结果表... 提出一种芯材开孔的新型全钢屈曲约束支撑,简称为PBRB.该支撑由开孔平板芯材,填充板及盖板通过螺栓连接而成.通过3根芯材具有不同开孔形式的PBRB试件的拟静力试验和相关数值分析,重点考察了芯材开孔形式对PBRB抗震性能的影响.研究结果表明:PBRB具有滞回性能稳定、延性高及累积耗能能力优良等特点;开孔芯材受压变形为压缩、剪切与弯曲组合的机制;开孔芯材"短柱"的长细比是影响PBRB性能的关键参数,芯材"短柱"长细比过大会造成PBRB滞回性能相对较差,基于试验结果给出了偏保守的设计长细比限制;同时提出了PBRB初始刚度的计算方法,评估精度良好. 展开更多
关键词 屈曲约束支撑 开孔 剪切 全钢制 滞回
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(Arylimido)vanadium(V)-Alkylidene Complexes as Catalysts for Ring-opening Metathesis Polymerization(ROMP) of Cyclic Olefins: Ligand Design for Exhibiting the High Activity
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作者 Kotohiro Nomura Sapanna Chaimongkolkunasin 《高分子科学:英文版》 SCIE CAS CSCD 2019年第10期943-950,I0002共9页
(Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalyt... (Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalytic activities for ringopening metathesis polymerization(ROMP) of norbornene(NBE). The catalytic activities were affected by the ligand substituents, and V(CHSiMe3)(N-2,6-Cl2C6H3)(OC6X5)(PMe3)2(X = F, Cl) demonstrated the exceptionally high catalytic activities for ROMP of NBE.The complexes polymerized cycloheptene(CHPE) and cis-cyclooctene(COE), and ROMP of COE by the OC6 Cl5 analogue proceeded in a living manner even at 80℃, and the activity increased with increasing the temperature up to 120 ℃. Highly active catalysts for ROMP of cyclic olefins(NBE, cyclopentene, and CHPE) can be generated in situ by premixing isolated V(CHSiMe3)(NC6F5)(O-2,6-iPr2C6H3)(PMe3)2 with 1.0 equiv. of C6F5OH or C6Cl5OH via immediate phenoxy exchange;the activity was affected by the kind of phenol added [TOF in the ROMPs of NBE: 4.62 × 10^4 min^–1(upon addition of C6F5OH) versus 37.3 min^–1(none)]. 展开更多
关键词 OLEFIN METATHESIS Molecular CATALYST RING-OPENING METATHESIS polymerization Cyclic OLEFIN VANADIUM CATALYST
The Principle of Detect SO2 Concentration by Using the Electrochemical Method in Ionic Liquid
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作者 HUANG Qing HU Yang +2 位作者 WANG Jiakai JIANG Kai WU Tian 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第5期400-404,共5页
The reduction of SO2 with different concentrations at a platinum microelectrode was investigated by cyclic voltammetry(CV) in 1-(butyl)-3-methylimidazolium hexafluorophosphate([Bmim]PF6). We speculated that the reacti... The reduction of SO2 with different concentrations at a platinum microelectrode was investigated by cyclic voltammetry(CV) in 1-(butyl)-3-methylimidazolium hexafluorophosphate([Bmim]PF6). We speculated that the reaction mechanism of reduction may form a macromolecular complex, and the higher the concentration of SO2, the larger the molecular weight of the complex. The higher the concentration of SO2, the greater the diffusion coefficient of SO2 in [Bmim]PF6. There is a good quadratic function relationship between the reduction peak current and SO2 concentrations in the range from 2% to 100%, which promises a kind of ionic liquid electrolyte for the detection of SO2 gas with a wide range of concentrations. 展开更多
关键词 IONIC liquids SULFUR dioxide cyclic VOLTAMMETRY chronoamperometric
VECTORIAL EKELAND VARIATIONAL PRINCIPLE AND CYCLICALLY ANTIMONOTONE EQUILIBRIUM PROBLEMS 预览
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作者 丘京辉 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第2期524-544,共21页
In this article, we extend the cyclic antimonotonicity from scalar bifunctions to vector bifunctions. We find out a cyclically antimonotone vector bifunction can be regarded as a family of cyclically antimonotone scal... In this article, we extend the cyclic antimonotonicity from scalar bifunctions to vector bifunctions. We find out a cyclically antimonotone vector bifunction can be regarded as a family of cyclically antimonotone scalar bifunctions. Using a pre-order principle(see Qiu, 2014), we prove a new version of Ekeland variational principle(briefly, denoted by EVP), which is quite different from the previous ones, for the objective function consists of a family of scalar functions. From the new version, we deduce several vectorial EVPs for cyclically antimonotone equilibrium problems, which extend and improve the previous results. By developing the original method proposed by Castellani and Giuli, we deduce a number of existence results(no matter scalar-valued case,or vector-valued case), when the feasible set is a sequentially compact topological space or a countably compact topological space. Finally, we propose a general coercivity condition. Combining the general coercivity condition and the obtained existence results with compactness conditions, we obtain several existence results for equilibrium problems in noncompact settings. 展开更多
关键词 EQUILIBRIUM problem: cyclic antimonotonicity vectorial EKELAND VARIATIONAL principle sequentially COMPACT TOPOLOGICAL SPACE countably COMPACT TOPOLOGICAL SPACE
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Modification of NiCoCrAlY with Pt: Part Ⅰ. Effect of Pt depositing location and cyclic oxidation performance
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作者 Yingfei Yang Hongrui Yao +2 位作者 Zebin Bao Pan Ren Wei Li 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第3期341-349,共9页
Pt layers of 5 μm in thickness were electroplated before or after depositing NiCoCrAlY coating by arc ion plating(AIP) aiming for identifying the effect of Pt enriching position on microstructure and cyclic oxidation... Pt layers of 5 μm in thickness were electroplated before or after depositing NiCoCrAlY coating by arc ion plating(AIP) aiming for identifying the effect of Pt enriching position on microstructure and cyclic oxidation behavior of Pt modified NiCoCrAlY coatings. Al-rich zones formed at the same position of Ptrich zones for both modified coatings due to uphill diffusion of Al driven by Pt. Cyclic oxidation tests at 1000 and 1100?C indicated that oxidation resistance of NiCoCrAlY was improved by Pt modification via different mechanisms: at surface, Pt-rich zone promoted selective oxidation of Al to form α-Al2O3,whilst at coating/substrate interface Pt-rich zone acted as effective diffusion barrier for titanium. Roles of Pt played in enhancing the oxidation performance of various Pt-modified NiCoCrAlY coating were investigated. 展开更多
关键词 CYCLIC oxidation Pt-modification NICOCRALY Electron probe micro-analysis(EPMA)
Utilization of Azobenzene Units to Control Zinc-mediated Ring Opening Polymerization of Cyclic Esters
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作者 SUN Junqi 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第5期747-748,共2页
Salicylaldimine Zn(Ⅱ) complexes bearing azobenzene moieties were prepared to catalyze ring opening polymerization of various cyclic esters. The different reactivities of the trans and cis isomers of the zinc complexe... Salicylaldimine Zn(Ⅱ) complexes bearing azobenzene moieties were prepared to catalyze ring opening polymerization of various cyclic esters. The different reactivities of the trans and cis isomers of the zinc complexes provide a facile strategy to control polymerization processes as well as the compositions of the resultant polymers. 展开更多
关键词 AZOBENZENE UNITS CONTROL Zinc-mediated Cyclic ESTERS
Lamin A/C Modulate Apoptosis of Rat Vascular Smooth Muscle Cells During Cyclic Stretch Application
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作者 Han Bao Haipeng Li +2 位作者 Qian Shi Kai Huang Yingxin Qi 《医用生物力学》 CAS CSCD 北大核心 2019年第A01期79-80,共2页
Objective The apoptosis of vascular smooth muscle cells(VSMCs)influenced by abnormal cyclic stretch is crucial for vascular remodeling during hypertension.We explored that the causes of mechano-responsive lamin A/C ch... Objective The apoptosis of vascular smooth muscle cells(VSMCs)influenced by abnormal cyclic stretch is crucial for vascular remodeling during hypertension.We explored that the causes of mechano-responsive lamin A/C changingin aonormai cyclic stretcn and its roles in VSMC apoptosis.Methods and results Our previous vascular proteomics study revealed that LaminA/C is mechano-sensitive molecule.When VSMCs are subjected to cyclic stretch,the expression of LaminA/C is significantly changed which participates dysfunctions of VSMCs during hypertension.However,the molecular mechanism involved in regulation of LaminA/C expression and the role of LaminA/C in the VSMC apoptosis during cyclic stretch application are still unclear.In the present study,VSMCs were subjected to different amplitudes of cyclic steetch in vitro:5%cyclic stretch(physiological strain)or 15%cyclic stretch(pathological strain).The expression of 2 different selective cleavage isomers of LaminA/C,i.e.LaminA and LaminC,and the apoptosis of VSMCs were detected.The results showed that compared with 5%group,15%cyclic stretch significantly decreased the expression of LaminA and LaminC,and promoted the apoptosis of VSMCs.Using specific small interfering RNA(siRNA)transfection which targets on LMNA the encoding gene of LaminA/C,the expression of LaminA and LaminC in VSMCs was significantly decreased,and the apoptosis was significantly increased.In order to study the molecular mechanism involved in cyclic stretch regulating the expression of LaminA/C,we focused on the microRNA(miR).Bioinformatics analysis showed that the 3’untranslated region(3’UTR)of LMNA has two potential binding sites to miR-124-3p.Double luciferase reported system revealed that both sites have binding abilities to miR-124-3p.Under static condition,miR-124-3p inhibitor significantly up-regulated the expression levels of LaminA and LaminC,while the miR-124-3p mimics significantly down-regulated them.RT-PCR results showed that 15%cyclic stretch significantly up-regulated the expression of mi 展开更多
关键词 LAMIN A/C Modulate APOPTOSIS Rat Vascular SMOOTH MUSCLE Cells Cyclic STRETCH APPLICATION
Cyclic posets and triangulation clusters
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作者 Kiyoshi Igusa Gordana Todorov 《中国科学:数学英文版》 SCIE CSCD 2019年第7期1289-1316,共28页
Triangulated categories coming from cyclic posets were originally introduced by the authors in a previous paper as a generalization of the constructions of various triangulated categories with cluster structures.We gi... Triangulated categories coming from cyclic posets were originally introduced by the authors in a previous paper as a generalization of the constructions of various triangulated categories with cluster structures.We give an overview, and then analyze "triangulation clusters" which are those corresponding to topological triangulations of the 2-disk. Locally finite nontriangulation clusters give topological triangulations of the "cactus space" associated to the "cactus cyclic poset". 展开更多
关键词 CACTUS CYCLIC POSET cluster structure triangulated CATEGORIES Frobenius CATEGORIES COCYCLE
Dual pitch titanium-coated pedicle screws improve initial and early fixation in a polyetheretherketone rod semi-rigid fixation system in sheep
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作者 Wen-Tao Wang Chi-Hua Guo +5 位作者 Kun Duan Min-Jie Ma Yong Jiang Tuan-Jiang Liu Ji-Jun Liu Ding-Jun Hao 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第21期2594-2600,共7页
Background:Reports on the efficacy of modifications to the thread design of pedicle screws are scarce.The aim of the study was to investigate initial and early fixation of pedicle screws with a plasma-sprayed titanium... Background:Reports on the efficacy of modifications to the thread design of pedicle screws are scarce.The aim of the study was to investigate initial and early fixation of pedicle screws with a plasma-sprayed titanium coating and dual pitch in the pedicle region(dual pitch titanium-coated pedicle screw[DPTCPS])in a polyetheretherketone(PEEK)rod semi-rigid fixation system.Methods:Fifty-four sheep spine specimens and 64 sheep were used to investigate initial(“0-week”controls)and early(postoperative 6 months)fixation,respectively.Sheep were divided into dual pitch pedicle screw(DPPS),standard pitch pedicle screw(SPPS),DPTCPS,and standard pitch titanium-coated pedicle screw(SPTCPS)groups.Specimens/sheep were instrumented with four screws and two rods.Biomechanical evaluations were performed,and histology at the implant-bone interface was investigated.Results:At 0-week,mean axial pull-out strength was significantly higher for the DPTCPS and SPTCPS than the SPPS(557.0±25.2 vs.459.1±19.1 N,t=3.61,P<0.05;622.6±25.2 vs.459.1±19.1 N,t=3.43,P<0.05).On toggle-testing,the DPTCPS was significantly more resistant than the SPPS and SPTCPS(343.4±16.5 vs.237.5±12.9 N,t=3.52,P<0.05;343.4±16.5 vs.289.9±12.8 N,t=3.12,P<0.05;124.7±13.5 vs.41.9±4.3 cycles,t=2.18,P<0.05;124.7±13.5 vs.79.5±11.8 cycles,t=2.76,P<0.05).On cyclic loading,maximum displacement was significantly lower for the DPTCPS than the SPPS and SPTCPS(1.8±0.13 vs.3.76±0.19 mm,t=2.29,P<0.05;1.8±0.13 vs.2.46±10.20 mm,t=2.69,P<0.05).At post-operative 6 months,mean axial pull-out strength was significantly higher for the DPTCPS and SPTCPS than the SPPS(908.4±33.6 vs.646.5±59.4 N,t=3.34,P<0.05;925.9±53.9 vs.646.5±59.4 N,t=3.37,P<0.05).On toggle-testing,the DPTCPS was significantly more resistant than the SPPS and SPTCPS(496.9±17.9 vs.370.3±16.4 N,t=2.86,P<0.05;496.9±17.9 vs.414.1±12.8 N,t=2.74,P<0.05;249.1±11.0 vs.149.9±11.1 cycles,t=2.54,P<0.05;249.1±11.0 vs.199.8±7.2 cycles,t=2.61,P<0.05).On cyclic loading,maximum displacement was significantl 展开更多
关键词 Dual pitch titanium coating Pedicle screws Axial pull-out Toggle testing Cyclic loading
全液体空分装置高低温膨胀流程形式的比较 预览
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作者 骞绍显 尹清猛 +1 位作者 乔彦彬 王剑 《低温与特气》 CAS 2019年第2期6-9,共4页
通过对全液体空分装置高低温膨胀流程进行不同的流路组织,经过对膨胀机组运行特点和换热器换热情况的分析比较,对不同的运行负荷要求如何选择更合适的流程形式做出了可行性的建议以达到能耗最优化的目的。
关键词 全液体空分装置 循环 换热 能耗 高低温膨胀 串联 并联
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Creep Model of High-Strength High-Performance Concrete Under Cyclic Loading
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作者 李倩 LIU Muyu +1 位作者 LU Zhifang 邓晓光 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第3期622-629,共8页
Concrete creep under both static and cyclic loading conditions was investigated. Four groups of high-strength high-performance concrete (HSHPC) prism specimens were fabricated, and three of these specimens were loaded... Concrete creep under both static and cyclic loading conditions was investigated. Four groups of high-strength high-performance concrete (HSHPC) prism specimens were fabricated, and three of these specimens were loaded periodically by the MTS Landmark Fatigue Testing Machine System. Creep characteristics and creep coefficients of HSHPC under static loading and cyclic loading, respectively, were obtained and compared. The experimental results show that the creep strains under cyclic loading with a mean stress of 0.4fcp and an amplitude of 0.2fcp increase significantly compared with the creep strains under static loading, and the maximum value was 1.2-2.3 times at early stages. In addition, the creep coefficient increases nonlinearly with the number of cyclic loading repetitions. The influence coefficient for cyclic loading 1.088x(N/N0)0.078was introduced based on the previous HSHPC creep model, and then the modified creep model under cyclic loading was established. Finally, the residual method, the CEB coefficient of variation method and the B3 coefficient of variation method were applied to evaluate the modified creep model. The statistical results demonstrate that the modified creep model agrees well with the experimental measurements. Hence, it has important theoretical and practical values for accurately predicting the deflection of concrete bridges under cyclic traffic loading. 展开更多
关键词 HSHPC CREEP model MODIFIED CYCLIC LOADING
On the Spectra of Strong Power Graphs of Finite Groups
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作者 Ruiqin FU Xuanlong MA 《数学研究及应用:英文版》 CSCD 2019年第5期453-458,共6页
Let G be a finite group of order n. The strong power graph of G is the undirected graph whose vertex set is G and two distinct vertices x and y are adjacent if x^n1 = y^n2 for some positive integers n1,n2 < n. In t... Let G be a finite group of order n. The strong power graph of G is the undirected graph whose vertex set is G and two distinct vertices x and y are adjacent if x^n1 = y^n2 for some positive integers n1,n2 < n. In this paper, we give the characteristic polynomials of the distance and adjacency matrix of the strong power graph of G, and compute its distance and adjacency spectrum. 展开更多
关键词 strong POWER graph CYCLIC group characteristic POLYNOMIAL spectrum
A new model for evaluating the dynamic shear strength of rocks based on laboratory test data for earthquake-resistant design 预览
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作者 Tetsuji Okada Tomohiro Naya 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第5期979-989,共11页
The dynamic shear strength of rocks is required for the earthquake-resistant design of nuclear power plants in Japan.This research aims to propose a mathematical model for estimating the dynamic strength and to valida... The dynamic shear strength of rocks is required for the earthquake-resistant design of nuclear power plants in Japan.This research aims to propose a mathematical model for estimating the dynamic strength and to validate the model.Two different types of specimens were prepared for the model validation,and the monotonic and cyclic loading tests were conducted to obtain the mathematical model parameters.Subsequently,multistep cyclic loading tests were performed,followed by simulations using the mathematical model.The test results demonstrated that the dynamic shear strength exceeded the static shear strength,which agreed with previous researches.Furthermore,the dynamic shear strength calculated using the mathematical model was generally consistent with that obtained from the experimental data. 展开更多
关键词 DYNAMIC SHEAR STRENGTH Static SHEAR STRENGTH CYCLIC loading Strain rate Fatigue Mathematical model
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Contribution of ghrelin to functional gastrointestinal disorders’pathogenesis 预览
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作者 Tilemachos Koutouratsas Theodora Kalli +1 位作者 Georgios Karamanolis Maria Gazouli 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第5期539-551,共13页
Functional gastrointestinal disorders(FGID)are heterogeneous disorders with a variety of clinical manifestations,primarily defined by signs and symptoms rather than a definite underlying cause.Their pathophysiology re... Functional gastrointestinal disorders(FGID)are heterogeneous disorders with a variety of clinical manifestations,primarily defined by signs and symptoms rather than a definite underlying cause.Their pathophysiology remains obscure and,although it is expected to differ according to the specific FGID,disruptions in the brain-gut axis are now thought to be a common denominator in their pathogenesis.The hormone ghrelin is an important component of this axis,exerting a wide repertoire of physiological actions,including regulation of gastrointestinal motility and protection of mucosal tissue.Ghrelin’s gene shows genetic polymorphism,while its protein product undergoes complex regulation and metabolism in the human body.Numerous studies have studied ghrelin’s relation to the emergence of FGIDs,its potential value as an index of disease severity and as a predictive marker for symptom relief during attempted treatment.Despite the mixed results currently available in scientific literature,the plethora of statistically significant findings shows that disruptions in ghrelin genetics and expression are plausibly related to FGID pathogenesis.The aim of this paper is to review current literature studying these associations,in an effort to uncover certain patterns of alterations in both genetics and expression,which could delineate its true contribution to FGID emergence,either as a causative agent or as a pathogenetic intermediate. 展开更多
关键词 FUNCTIONAL GASTROINTESTINAL disorders FUNCTIONAL colonic diseases Irritable bowel SYNDROME Cyclic VOMITING SYNDROME Infantile COLIC GASTROINTESTINAL disease GHRELIN Genetics Epigenetic processes
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Effect of High-Stress Equal Amplitude Cyclic Loading on Mechanical and Deformation Characteristics of Rubber Concrete 预览
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作者 Xin Huang Yu Chen 《建筑发展研究》 2019年第5期1-4,共4页
In order to study the mechanical and deformation characteristics of rubber concrete under repeated loading,50 cycles of high-stress equal amplitude cyclic loading and uniaxial compression tests were carried out on 30 ... In order to study the mechanical and deformation characteristics of rubber concrete under repeated loading,50 cycles of high-stress equal amplitude cyclic loading and uniaxial compression tests were carried out on 30 concrete specimens of 5 groups.The change of uniaxial mechanical properties and the deformation during cyclic loading of normal concrete(NC)and rubber concrete(RC)with 5%,10%,15%,and 20%content were analysed.The results show that the peak stress and modulus of elasticity decrease and the peak strain increases with the increase of rubber content.After cyclic loading,the degradation degree of NC peak stress and elastic modulus reached 11.0%and 36.8%respectively.This study can provide a basis for the application of rubber concrete. 展开更多
关键词 Rubber concrete CYCLIC loading MECHANICAL properties TOTAL STRAIN
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Kinetics and mechanistic investigation of epoxide/CO2 cycloaddition by a synergistic catalytic effect of pyrrolidinopyridinium iodide and zinc halides 预览
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作者 Abdul Rehman Valentine C. Eze +1 位作者 M.F.M.Gunam Resul Adam Harvey 《能源化学:英文版》 CSCD 2019年第10期35-42,共8页
Formation of styrene carbonate (SC) by the cycloaddition of CO2 to styrene oxide (SO) catalysed by pyrrolidinopyridinium iodide (PPI) in combination with zinc halides (ZnCl2, ZnBr2 and ZnI2) was investigated. Complete... Formation of styrene carbonate (SC) by the cycloaddition of CO2 to styrene oxide (SO) catalysed by pyrrolidinopyridinium iodide (PPI) in combination with zinc halides (ZnCl2, ZnBr2 and ZnI2) was investigated. Complete conversion of the SO to SC was achieved in 3 h with 100% selectivity using 1/0.5 molar (PPI/ZnI2) catalyst ratio under mild reaction conditions i.e., 100℃ and 10 bar CO2 pressure. The synergistic effect of ZnI2 and PPI resulted in more than 7-fold increase in reaction rate than using PPI alone. The cycloaddition reaction demonstrated the first-order dependence with respect to the epoxide, CO2 and catalyst concentrations. Moreover, the kinetic and thermodynamic activation parameters of SC formation were determined using the Arrhenius and Eyring equations. The positive values of △H(42.8 kJ mol^-1) and △G(102.3 kJ mol^-1) revealed endergonic and chemically controlled nature of the reaction, whereas the large negative values of △S(-159.4 J mol^-1 K^-1) indicate a highly ordered activated complex at the transition state. The activation energy for SC formation catalyzed by PPI alone was found to be 73.2 kJ mol^-1 over a temperature range of 100-140℃, which was reduced to 46.1 kJ mol^-1 when using PPI in combination with ZnI2 as a binary catalyst. Based on the kinetic study, a synergistic acid-based reaction mechanism was proposed. 展开更多
关键词 CYCLOADDITION CO2 utilization Cyclic CARBONATES Homogeneous catalysis Activation energy
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