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Cerebral and muscle tissue oxygenation during exercise in healthy adults: A systematic review

Journal of Sport and Health Science 2024年第4期13卷 459-471,F0003页

作者： Diego Orcioli-Silva Victor Spiandor Beretta Paulo Cezar Rocha Santos Felipe Marroni Rasteiro Anita Brum Marostegan Rodrigo Vitorio Claudio Alexandre Gobatto Fulvia Barros Manchado-Gobatto Laboratory of Applied Sport Physiology(LAFAE) School of Applied Sciences(FCA)University of Campinas(UNICAMP)Limeira 13484-350Brazil Posture and Gait Studies Laboratory(LEPLO) Institute of BiosciencesSao Paulo State University(UNESP)Rio Claro 13506-900Brazil Physical Education Department School of Technology and SciencesSao Paulo State University(UNESP)Presidente Prudente 19060-900Brazil Department of Computer Science&Applied Mathematics Weizmann Institute of ScienceRehovot 7610001Israel Center of Advanced Technologies in Rehabilitation Sheba Medical CenterRamat Gan 5265601Israel Department of Sport Exercise and RehabilitationNorthumbria UniversityNewcastle upon Tyne NE18STUK

Background:Near-infrared spectroscopy(NIRS)technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during *** this technology has been growing and is now successfully used in laboratory and sports settings,this systematic review aimed to synthesize the evidence and enhance an integrative understanding of bloodﬂow adjustments and oxygen(O_(2))changes(i.e.,the balance between O_(2) delivery and O_(2) consumption)within the cerebral and muscle systems during ***:A systematic review was conducted using PubMed,Embase,Scopus,and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during *** review considered manuscripts written in English and available before February 9,*** step of screening involved evaluation by 2 inde-pendent authors,with disagreements resolved by a third *** Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the ***:Twenty studies were included,of which 80%had good methodological quality,and involved 290 young or middle-aged *** types of exercises were used to assess cerebral and muscle hemodynamic changes,such as cycling(n=11),treadmill(n=1),knee extension(n=5),isometric contraction of biceps brachii(n=3),and duet swim routines(n=1).The cerebral hemodynamics anal-ysis was focused on the frontal cortex(n=20),while in the muscle,the analysis involved vastus lateralis(n=18),gastrocnemius(n=3),biceps brachii(n=5),deltoid(n=1),and intercostal muscle(n=1).Overall,muscle deoxygenation increases during exercise,reaching a plateau in voluntary exhaustion,while in the brain,oxyhemoglobin concentration increases with exercise intensity,reaching a plateau or declining at the exhaustion ***:Muscle and cerebral oxygenation respond differently to exercise,with muscle

关键词： Near-infrared spectroscopy Hemodynamic Blood flow Brain Muscle metabolism

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等离子体喷射触发型SF_(6)和SF_(6)/N_(2)间隙开关的触发性能劣化规律

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电网技术 2024年第7期48卷 3084-3090,I0120-I0121页

作者：李晓昂蒋攀李志兵张然王海晖赵科张乔根电力设备电气绝缘国家重点实验室(西安交通大学) 陕西省西安市710049 中国电力科学研究院有限公司北京市海淀区100192 国网江苏省电力公司电力科学研究院江苏省南京市210036

在江苏—白鹤滩±800 kV特高压混合直流输电工程中,采用等离子体喷射触发型气体间隙开关可以对可控避雷器进行旁路控制,具有响应速度快,绝缘恢复能力强,通流容量大等优势,应用前景广泛,但触发间隙气体氛围的优化选择尚有所缺失,间隙触... 详细信息

在江苏—白鹤滩±800 kV特高压混合直流输电工程中,采用等离子体喷射触发型气体间隙开关可以对可控避雷器进行旁路控制,具有响应速度快,绝缘恢复能力强,通流容量大等优势,应用前景广泛,但触发间隙气体氛围的优化选择尚有所缺失,间隙触发特性和寿命的提升仍有待进一步研究。搭建了等离子体喷射触发实验平台,研究了等离子体喷射触发气体间隙的触发性能劣化规律,分别在SF_(6)和SF_(6)/N_(2)混合气体中探究了间隙触发的临界电路参数,在确定的电路参数下进行触发寿命实验同时探究性能劣化规律。结果表明:相同绝缘强度下,当间隙电压为10 kV时,0.2 MPa SF_(6)氛围下间隙最低可触发电压为3.5 k V,而在0.266 MPa SF_(6)/N_(2)氛围下降低为2.6 kV;在最佳触发电路参数条件和相同绝缘强度下,实验初期,SF_(6)中间隙导通时延为~270μs,等离子体最大喷射高度为4.8 cm,最大喷射速度为1296 m/s,而在SF_(6)/N_(2)中间隙导通时延为~100μs,等离子体最大喷射高度为7.2 cm,最大喷射速度为1525 m/s,而随着放电次数的增加,间隙导通时延增加,等离子体最大喷射高度降低,最大喷射速度减小,直到间隙第一次触发失败达到间隙寿命,SF_(6)中间隙的触发寿命仅有695次,而SF_(6)/N_(2)混合气体中间隙的触发寿命达到了1540次。对可控避雷器用气体间隙触发开关的性能和寿命提升提供了理论指导,同时有助于其在工程领域推广应用。

关键词：气体氛围触发特性触发寿命性能劣化 SF_(6)和SF_(6)/N_(2)混合气体

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Mechanical properties and tribological behavior of a cast heat-resisting copper based alloy

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Journal of Central South University of Technology 2002年第4期9卷 235-239页

作者：张卫文夏伟温利平吴苑标潘国如 College of Mechanical Engineering South China University of Technology

Mechanical properties and tribological behavior of a novel cast heat resisting copper based alloy are investigated. The corresponding properties of a commercial aluminum bronze C95500 (ASTM B30) are compared with the alloy. The results show that the alloy possesses better mechanical properties and tribological behaviors than that of C95500 at elevated temperature. The tensile strength, elongation and hardness at 500℃ are 470MPa, 2.5% and HB220, respectively. The wear rate of the developed alloy at ambient and elevated temperature is about one sixth and one fortieth of that of C95500, respectively. The alloy is very suitable for ma nufacturing heat resisting and wear resisting parts. Major strengthening mechanisms for the alloy are solution strengthening and the second phase strengthening.

关键词： copper based alloy heat-resisting mechanical property tribological behavior

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抗静电天冬聚脲弹性耐磨自洁地坪涂料的研制

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现代涂料与涂装 2024年第9期27卷 9-11页

作者：胡晓伟广东坚派新材料有限公司

介绍了一种抗静电天冬聚脲弹性耐磨自洁地坪涂料的研制及抗静电涂层设计方案，对电子、医药、物联网等领域提供了一种有效的抗静电地坪材料。该涂层由导电的底漆、天冬聚脲中涂及天冬聚脲面漆组成，表面电阻值3.0×1 0 6Ω，具有抗静电... 详细信息

介绍了一种抗静电天冬聚脲弹性耐磨自洁地坪涂料的研制及抗静电涂层设计方案，对电子、医药、物联网等领域提供了一种有效的抗静电地坪材料。该涂层由导电的底漆、天冬聚脲中涂及天冬聚脲面漆组成，表面电阻值3.0×1 0 6Ω，具有抗静电、弹性、耐磨、自洁、耐黄变等诸多优点，在高端地坪领域显示出良好的应用前景。

关键词：天冬聚脲地坪涂料抗静电弹性自洁耐黄变

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Microspheres Sensor Based on Molecularly Imprinted Polymer Synthesized by Precipitation Polymerization

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Chinese Journal of Chemistry 2003年第5期21卷 550-555页

作者：张朝晖龙玉梅刘英菊姚守拙 State Key Laboratory of Chemo/Biosensing & Chemometrics Hunan University Changsha Hunan 410082 China

A new biomimetic bulk acoustic wave sensor based on molecularly imprinted microspheres (MUM) technique was described. The sensing materials were synthesized by precipitation polymerization. By using the Scatchard analysis, the equilibrium dissociation constant K-D and the apparent maximum number Q(max) of the binding sites were calculated to be 3.70 mmol (.) L-1 and 9.11 mumol (.) g(-1), respectively. The sensor exhibited a sensitive response to the template compound (dipyridamole) in liquid phase with a detection Unfit of 2 x 10(-9) mol (.) L-1. The recoveries of the sensor were 95.1%-105.4%. Studies presented in this paper show that the stability of this sensor is excellent. The sensor has been applied successfully to the determination of dipyridamole in human urine.

关键词： microspheres sensor molecularly imprinted polymer dipyridamole precipitation polymerization

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Prediction of Molar Absorptivities of Color Reagents and Their Color Reactions with Yttrium by Artificial Neural Networks

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Journal of Rare Earths 2000年第4期18卷 302-307页

作者：李华许禄苏锵 Institute of Analytical Science Northwest University Xi'an 710069 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The new topological indices A x1 A x3 suggested in our laboratories were applied to the study of structure property relationships between color reagents and their color reactions with yttrium. The topological indices of twenty asymmetrical phosphone bisazo derivatives of chromotropic acid were calculated. The work shows that QSPR can be used as a novel aid to predict the molar absorptivities of color reactions and in the long term to be helpful tool in color reagent design. Multiple regression analysis and neural network were employed simultaneously in this study. The results demonstrated the feasibility and the effectiveness of the method.

关键词： rare earths yttrium color reagents quantitative structure property relationships neural networks

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Electrochemical Behavior of Mitoxantrone and Its Determination at a Pt/C Implanted Modified Microelectrode

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Chemical Research in Chinese Universities 2004年第1期20卷 103-107页

作者： QIANYong-gui SUNZi-jie HUJing-bo LUYi-qiang LIQi-long DepartmentofChemistry BeijingNormalUniversityBeijing100875P.R.China DepartmentofChemistry BeijingUniversityofScienceandTechnologyBeijing100083P.R.China

In a 0.02 mol/L Na_2HPO_4-KH_2PO_4(PBS) buffer solution(pH=6.82), the electrochemical behavior of mitoxantrone was studied by linear-sweep voltammetry and cyclic voltammetry at a Pt/C ion implantation modified microelectrode. A sensitive reduction peak was observed. The peak potential was \{-0.72 V\}(***), the peak current was proportional to the concentration of mitoxantrone within the ranges of 7.0×10 -8—9.0×10 -7 mol/L and 1.0×10 -6—2.4×10 -5 mol/L, with a detection limit of 4.0×10 -8 mol/L. The linear correlation coefficients were 0.9994 and 0.9992, respectively. This method has been applied to the direct determination of mitoxantrone in simulated urine. The recoveries were in the range from 96.2% to 105.9%. The reduction process was a quasi-reversible one with adsorptive characteristics at the Pt/C microelectrode. The electrode reaction rate constant k_s and the electron transfer coefficient α of the system were determined to be 4.5 and 0.65 s -1, respectively. The experiments showed that Pt element had surely been implanted into the surface of the carbon fiber, and the atomic Pt improved the electrocatalytic activity. The Pt/C microelectrode had a good stability and reproducibility.

关键词： Mitoxantrone Electrochemical behavior Ion implantation Modified microelectrode

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Fragmentation Mechanism of Trans-α-Aryl-β-enamino Esters

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Chinese Journal of Chemistry 2002年第8期20卷 789-794页

作者：蒋楠王剑波何美玉 College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Electron impact induced fragmentation mechanisms of trans α aryl β enamino esters were investigated using mass analyzed ion kinetic energy (MIKE) spectrometry and high resolution accurate mass data. It was found that the main characteristic fragmentations of compounds studied were: an odd electron ion M +· -EtOH was formed by losing a neutral molecule of ethanol; and the skeletal rearrangements took place; and the ring opening reaction happened after losing a carbon monoxide; and the typical McLafferty rearrangement underwent in ester group. The cyclization reaction caused by losing neutral molecule of TsNH 2 due to the ortho effects of substituted group of aromatic ring was also observed.

关键词： aryl β enamino esters mechanism MIKES skeletal rearrangement cyclization reaction

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Effect of Flux on Properties of Structure and Luminescence of LaMgB_5O_(10)∶Ce^(3+), Mn^(2+)

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Journal of Rare Earths 2004年第S1期22卷 80-83页

作者：常树岚方英玉李承范 Department of Chemistry Science and Engineering College Yanbian University Yanji 133002 China

The influences of the flux KCl or KF on the XRD spectra, cell parameters and crystal appearance, and spectral properties of the phosphor LaMgB_5O_(10)∶Ce^(3+), Mn^(2+) were studied. The results indicate that when 4.2%, 8.6%, 12.8% KCl and 5.3%, 10.5%KF are respectively added into phosphor (La_(0.85)Ce_(0.15)) (Mg_(0.9)Mn_(0.1))B_5O_(10), compared with the normal card of JCPDS (No 35-120), the intensity of XRD spectra is enhanced, the values corresponded to 17/28, 18/28, 16/28, 18/28 and 2/28 and the cell parameters diminish because of the flux KCl and KF. The use of 5% KCl a fraction of Cu monocrystals are observed in the phosphor. There are six hexagonal crystal-faces and eight triangular crystal-faces representing crystal-face index {100} and {111}. When 15% KCl is added to the phosphor, law of crystal plane and self-regulaton are formed, the emission intensity of Ce^(3+) 5d-4f ((()~2F_(5/2),) (()~2F_(7/2))) and Mn^(2+) ((()~4G) and (()~6S)) increases by 3.41 times and 2.36 times respectively.

关键词： inorganic materials flux luminescence rare earths

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Synthesis of Amino Acid Derived β-Cyclodextrins Used in Chiral Separation by Capillary Electrophoresis

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Journal of Beijing Institute of Technology 2004年第2期13卷 206-209页

作者：戴荣继佟斌魏征顾峻岭邓玉林李明愉傅若农 School of Life Science and Technology Beijing Institute of Technology Beijing100081 China School of Material Science and Engineering Beijing Institute of Technology Beijing100081 China School of Science Beijing Institute of Technology Beijing100081 China School of Mechatronics Engineering Beijing Institute of Technology Beijing 100081 China

Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis{2,6-di-O-[3-L-(1-isopropyl carboxyl methyl amino)-2-(hydroxy) propyl]}-β-cyclodextrin (i.e. L-Val-β-CD), heptakis{2,6-di-O-[3-L-(1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Phe-β-CD), heptakis{2,6-di-O-[3-(D, L-1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. D,L-Phe-β-CD), heptakis{2,6-di-O-[3-(L-1-hydroxymethyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Ser-β-CD), heptakis{2,6-di-O-[3-(L-1-carboxylmethyl carboxyl methyl amino)- 2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Asp-β-CD), heptakis{2,6-di-O-[3-(L-2-carboxyl tetramethylene amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Pro-β-CD). Their chemical structures were certified using FTIR and ()~1H NMR. Except for L-Phe-β-CD and D,L-Phe-β-CD, that are in soluble in water, the other amino acid derived β-CDs all have good water solubility. D,L-tyrosine and promethazine were baselinely separated by L-Val-β-CD in capillary electrophoresis.

关键词： cyclodextrin derivatives capillary electrophoresis chiral selector

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