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化工进展 2025年

作者：房玉宝张西龙青岛理工大学机械与汽车工程学院

采用两步法制备了质量分数为0.5%的Cu-h2O和Al2O3-h2O两种纳米流体。依次分析了多个因素对纳米流体稳定性的影响，包括超声处理时间、分散剂种类、分散剂添加浓度以及ph值等。实验发现，针对不同类型的纳米流体，均存在各自的最佳超声... 详细信息

采用两步法制备了质量分数为0.5%的Cu-h2O和Al2O3-h2O两种纳米流体。依次分析了多个因素对纳米流体稳定性的影响，包括超声处理时间、分散剂种类、分散剂添加浓度以及ph值等。实验发现，针对不同类型的纳米流体，均存在各自的最佳超声处理时间、ph值及合适的分散剂类型，Cu-h2O和Al2O3-h2O这两种纳米流体的最佳分散剂分别为十二烷基苯磺酸钠（SDBS）和聚乙烯吡咯烷酮（PVP），最佳超声处理时间均为60min左右，最佳ph值分别为8和4。当添加分散剂的质量分数为0.5%时，纳米流体的分散稳定性表现得最好。此外，本文还提出了一种基于沉淀观察法的量化表征纳米流体稳定性的表达式，通过这一方法，可以更为准确地确定制备纳米流体的最佳方案和配比，从而为今后的相关研究和应用提供了重要的参考依据。

关键词：纳米流体稳定性沉淀观察法 Cu-h O纳米流体 Al O -h O纳米流体

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Room-temperature densified Al 2 O 3 -h 3 BO 3 ceramics with excellent microwave dielectric properties and thermal conductivity for chip packaging

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Journal of Materiomics 2025年

作者： Zhan Zeng Jin Cheng Xinwei Xu hongye Wang Yani Lu Liang Sun Naichao Chen Xiaoyu Li Boshen Zhang hong Wang Department of Materials Science and Engineering Southern University of Science and Technology Shenzhen 518055 Guangdong China Guangdong Provisional Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology Shenzhen 518055 Guangdong China

As electronic devices become increasingly miniaturized and demand greater integration, traditional packaging technologies face substantial challenges in meeting the needs for high-frequency performance and system reliability. Ceramic materials, known for their excellent dielectric properties and thermal stability, are promising candidates for advanced packaging applications. however, conventional high-temperature densification processes, which often exceed 1000 °C, restrict their compatibility with temperature-sensitive components in modern electronic systems. To overcome this limitation, we propose a novel approach to densify Al 2 O 3 -h 3 BO 3 ceramic at room temperature under low uniaxial stress. It is found that a h 3 BO 3 facilitates plastic deformation in the medium of deionized water, enhancing the densification of Al 2 O 3 -h 3 BO 3 ceramics even at minimal uniaxial stress. The resulting material exhibits a high relative density of over 96% and possesses excellent microwave dielectric properties (relative permittivity : 2.84–5.37; values: 12,924–69,000 Ghz; resonant frequency values: −156.94 10 –6 ·°C –1 to −73.42 10 –6 ·°C –1 ) and thermal conductivity ( values: 1.96–5.96 W·m –1 ·K –1 ). After co-firing with a silicon wafer, the ceramic maintains its structural integrity, with no observable atomic diffusion at the ceramic-silicon interface, rendering it a potential candidate for advanced packaging and integration technologies.

关键词： room-temperature densification Al 2 O 3 -h 3 BO 3 ceramics microwave dielectric properties thermal conductivity 3D heterogeneous integration

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RECONSTITUTED AMILORIDE-INhIBITED SODIUM TRANSPORTER FROM RABBIT KIDNEY MEDULLA IS RESPONSIBLE FOR NA+-h+ EXChANGE

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BIOChIMICA ET BIOPhYSICA ACTA 1984年第1期770卷 79-92页

作者： LABELLE, EF UNIV TEXAS MED BRANCH DEPT HUMAN BIOL CHEM & GENET GALVESTON TX 77550 USA

Microsomes formed from rabbit kidney medulla and reconstituted proteoliposomes formed from these microsomes were capable of amiloride-inhibited Na+ transport that was insensitive to valinomycin either with or without K+. This indicated that the Na+ transport process was electroneutral. This Na+ transport process was insensitive to extravesicular Cl- or hCO3- and not stimulated by high intravesicular gradients of K+, Ca2+ or Mg2+, which indicated that the process did not require NaCl or NahCO3 co-transport or Na.+-./K+, Na+/Ca2+ or Na+/Mg2+ counter-transport. Na+ uptake into microsomes or proteoliposomes was inhibited by extravesicular K+, C2+, Mg2+ or La3+, which indicated that these ions interacted with the Na+-binding site on the transport protein. Na+ uptake into microsomes was stimulated by intravesicular protons and inhibited by extravesicular proteons. Microsomes may be capable of Na+-h+ exchange and this was confirmed when Na+ was shown to stimulate h+ efflux from microsomes. The amiloride-inhibited Na+ transporter from medulla microsomes which was reconstituted into proteoliposomes, is most likely a Na+-h+ exchanger. This Na+ transporter was totally insensitive to the uncoupler 1799, either in the presence or absence of valinomycin plus K+ and less sensitive to Nh3 than to amiloride. Apparently, amiloride inhibited Na+ transport not merely by acting as a weak-base uncoupler but by directly interacting with the protein responsible for Na+-h+ exchange.

关键词： Na + transport Amiloride inhibition Na + -h + exchange (Rabbit kidney) hepes 4-(2-hydroxyethyl)-1-piperazineethane-sulfonic acid hepps 4-(2-hydroxyethyl)-1-piperazinepropane-sulfonic acid Tris tris(hydroxymethyl)aminomethane Mes 4-morpholineethanesulfonic acid 1799 bis(hexafluoracetonyl) acetone

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Infarct size limitation by a new Na+-h+ exchange inhibitor, hoe 642: Difference from preconditioning in the role of protein kinase C

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JOURNAL OF ThE AMERICAN COLLEGE OF CARDIOLOGY 1997年第3期29卷 693-701页

作者： Miura, T Ogawa, T Suzuki, K Goto, M Shimamoto, K Second Department of Internal Medicine Sapporo Medical University School of Medicine Sapporo Japan.

Objectives. This study examined the effect of a new specific Na+-h+ exchange inhibitor, hoe 642, on infarct size and the protective role of protein kinase C (PKC) by this agent. In addition, we assessed the possible alteration of hoe 642-induced cardioprotection by commonly used animal anesthetic drugs. Background. Earlier studies on the contribution of Na+-h+ exchange to ischemic injury were complicated by nonspecific actions of the Na+-h+ exchange inhibitors, and the role of this exchanger in myocardial infarction in vivo remains unclear. The difference in anesthetic agents used in experiments could have resulted in discrepant findings regarding cardioprotection of some interventions, such as preconditioning and adenosine triphosphate-sensitive potassium channel openers. Methods. Infarction was induced by 30 min of coronary occlusion and 3 h of reperfusion in the rabbit heart. In the first series of experiments, rabbits were anesthetized with pentobarbital or ketamine/xylazine. hoe 642 was injected intravenously 10 min before ischemia or 5 ruin before reperfusion. In the second series of experiments, rabbits received 25 mg/kg body weight of polymyxin B (polyB), hoe 642 plus polyB, preconditioning with 5 min of ischemia and 5 min of reperfusion plus polyB or preconditioning alone before 30 min of ischemia. Results. In pentobarbital-anesthetized rabbits, 0.3 mg/kg and 0.6 mg/kg of hoe 642 given before ischemia limited infarct size (as percent area at risk [%IS/AR]) to 42.7 +/- 4.4% (SEM) and 26.2 +/- 5.4%, respectively, from the control value of 55.1 +/- 3.5%. however, injection of hoe 642 before reperfusion did not change infarct size (%IS/AR 49.6 +/- 4.9%, p = 0.387;power 0.81 for detecting 50% reduction). Infarct size limitation by the preischemic treatment with hoe 642 was similarly observed in the rabbits anesthetized with ketamine/xylazine. In the polyB-treated rabbits, 0.6 mg/kg of hoe 642 significantly limited infarct size (%IS/AR was 28.3 +/- 3.8% with hoe

关键词： ANOVA analysis of variance EIPA ethylisopropyl amiloride %IS/AR infarct size as percent area at risk K atp ATP-sensitive potassium channel MIA methylisobutyl amiloride NhE-1 Na + -h + exchange type 1 PC preconditioned PKC protein kinase C polyB polymyxin B TTC triphenyltetrazolium

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NA+-h+ EXChANGE IN CARDIAC SARCOLEMMAL VESICLES

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BIOChIMICA ET BIOPhYSICA ACTA 1985年第2期818卷 109-116页

作者： PIERCE, GN PhILIPSON, KD UNIV CALIF LOS ANGELES CTR HLTH SCI SCH MED DEPT MED LOS ANGELES CA 90024 USA UNIV CALIF LOS ANGELES CTR HLTH SCI SCH MED DEPT PHYSIOL LOS ANGELES CA 90024 USA UNIV CALIF LOS ANGELES CTR HLTH SCISCH MEDAMER HEART ASSOC GREATER LOS ANGELES AFFILIATE LOS ANGELES CA 90024 USA

The transport of Na+ by a purified sarcolemmal vesicular preparation from canine ventricular tissue was studied as a function of both internal and external ph. The uptake of Na+ into sarcolemmal vesicles increased upon raising the extravesicular ph of the reaction medium. half-maximal uptake of Na+ was observed at a pho of about 8.1 and maximal uptake occurred at ph 8.6. The uptake of Na+ by sarcolemma was also dependent upon the intravesicular ph. Na+ uptake into sarcolemmal vesicles was greatly attenuated in the absence of a h+ gradient across the membrane. Transport of Na+ was potently inhibited by amiloride, a known blocker of Na+-h+ exchange. LiCl was also an effective inhibitor of Na+ transport. In the presence of optimal h+ gradients, Na+ uptake was linear for the first 5 seconds of the reaction and exhibited a Vmax of 290 nmol Na+/mg per min and a KNa of 3.5 mM. These experiments strongly indicate the presence of a Na+-h+ exchange system in cardiac sarcolemma. This activity appeared to be relatively specific for this membrane fraction. The identification of Na+-h+ exchange activity in a sarcolemmal vesicular fraction from the heart will permit extensive characterization of the regulation and kinetics of this antiporter in future investigations.

关键词： Na + transport Na + -h + exchange Sarcolemmal membrane Kinetics (Dog heart) EGTA ethylene glycol bis( β -aminoethyl ether)- N , N ′-tetraacetic acid Caps 3-(cyclohexylamino)-1-propane-sulfonic acid Ches 2-(cyclohexylamino)ethanesulfonic acid hepes 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid Mes 4-morpholineethanesulfonic acid Taps 3-[tris(hydroxymethyl)methyl]aminopropanesulfonic acid

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ThE LIPID FLUIDITY OF RAT COLONIC BRUSh-BORDER MEMBRANE-VESICLES MODULATES NA+-h+ EXChANGE AND OSMOTIC WATER PERMEABILITY

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BIOChIMICA ET BIOPhYSICA ACTA 1986年第1期855卷 16-24页

作者： BRASITUS, TA DUDEJA, PK WORMAN, hJ FOSTER, ES MICHAEL REESE HOSP & MED CTR DEPT MED DIV GASTROENTEROL CHICAGO IL 60616 USA UNIV CHICAGO PRITZKER SCH MED CHICAGO IL 60637 USA

Brush-border membrane vesicles were prepared from rat colonic epithelial cells. Steady-state fluorescence polarization techniques, using the fluorophores 1,6-diphenyl-1,3,5-hexatriene and DL-12-(9-anthroyl)stearic acid (12-AS), revealed that benzyl alcohol (25-75 mM) but not methyl alcohol (50-125 mM) significantly increased the fluidity of these vesicles. Benzyl alcohol (50 and 75 mM) but not methyl alcohol also increased amiloride-sensitive sodium-stimulated proton efflux from these vesicles at all concentrations of sodium tested (2.5-50.0 mM), as assessed by changes in the fluorescence of acridine orange. Benzyl alcohol, at 50 and 75 mM concentrations, increased the maximal velocity (Vmax) of this exchange process by approximately 58 and 75%, respectively. Neither concentration, however, altered the Km for sodium. Osmotic water flow, measured as rate constants of osmotic shrinkage of these vesicles using a stopped-flow nephelometric technique, was also increased by 75 mM benzyl alcohol but not by a similar concentration of methyl alcohol. The present data, therefore, demonstrate that the fluidity of rat colonic brush-border membranes can influence Na+-h+ exchange and osmotic water flow across these vesicles.

关键词： Brush-border membrane Membrane fluidity Na + -h + exchange Water permeability Fluorescence polarization Steady-state fluorescence (Rat intestine)

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Mitochondrial ATP-sensitive K⁺ channels play a role in cardioprotection by Na⁺-h⁺ exchange inhibition against ischemia/reperfusion injury

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JOURNAL OF ThE AMERICAN COLLEGE OF CARDIOLOGY 2001年第3期37卷 957-963页

作者： Miura, T Liu, YG Goto, M Tsuchida, A Miki, T Nakano, A Nishino, Yh Ohnuma, Y Shimamoto, K Sapporo Med Univ Sch Med Dept Internal Med 2 Chuo Ku Sapporo Hokkaido 0600061 Japan Otsuka Amer Pharmaceut Inc Maryland Res Lab Rockville MD USA

OBJECTIVES The possible role of the ATP-sensitive potassium (K-ATP) channel in cardioprotection by Na+-h+ exchange (NhE) inhibition was examined. BACKGROUND The K-ATP channel is suggested to be involved not only in ischemic preconditioning but also in some pharmacological cardioprotection. METhODS Infarction was induced by 30-min coronary occlusion in rabbit hearts in situ or by 30-min global ischemia in isolated hearts. Myocardial stunning was induced by five episodes of 5-min ischemia/5-min reperfusion in situ. In these models, the effects of NhE inhibitors (cariporide and ethylisopropyl-amiloride [EIPA]) and the changes caused by K-ATP channel blockers were assessed. In another series of experiments, the effects of EIPA on mitochondrial K-ATP (mito-K-ATP) and sarcolemmal K-ATP (sarc-K-ATP) channels were examined in isolated cardiomyocytes. RESULTS Cariporide (0.6 mg/kg) reduced infarct size in situ by 40%, and this effect was abolished by glibenclamide (0.3 mg/kg), a nonselective K-ATP channel blocker. In vitro, 1 muM cariporide limited infarct size by 90%, and this effect was blocked by 5-hydroxydecanoate (5-hD), a mito-K-ATP channel blocker but not by hMR1098, a sarc-K-ATP channel blocker. Infarct size limitation by 1 muM EIPA was also prevented by 5-hD. Cariporide attenuated regional contractile dysfunction by stunning, and this protection was abolished by glibenclamide and 5-hD. Ethylisopropyl amiloride neither activated the mito-K-ATP channel nor enhanced activation of this channel by diazoxide, a K-ATP channel opener. CONCLUSIONS Opening of the mito-K-ATP channel contributes to cardioprotection by NhE inhibition, though the interaction between NhE and this K-ATP channel remains unclear. (J Am Coil Cardiol 2001;37:957-63) (C) 2001 by the American College of Cardiology.

关键词： EIPA ethylisopropyl amiloride I K.ATP sarc-K ATP channel current LV left ventricle or left ventricular LVDP left ventricular developed pressure LV dP/dt the first derivative of left ventricular pressure mito-K ATP mitochondrial K ATP channel NhE Na + -h + exchanger sarc-K ATP sarcolemmal K ATP channel TTC triphenyltetrazolium chloride 5-hD 5-hydroxydecanoate

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EFFECT OF ThE PREPARATION METhOD ON NA+-h+ EXChANGE AND ION PERMEABILITIES IN RAT RENAL BRUSh-BORDER MEMBRANES

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BIOChIMICA ET BIOPhYSICA ACTA 1984年第2期772卷 140-148页

作者： SABOLIC, I BURCKhARDT, G MAX PLANCK INST BIOPHYS KENNEDYALLEE 70D-6000 FRANKFURTFED REP GER

The Δph-dependent quenching of Acridine orange was used to characterize Na + -h + exchange and K + and h + conductances in brush-border membrane vesicles isolated by precipitation with either CaCl 2 or MgCl 2 from rat kidney cortex. A transmembrane ph difference of 2.5 units (inside acidic) was imposed and the initial rate of its dissipation was followed after injecting a puls of tetramethylammonium gluconate (control) or sodium or potassium gluconate. In membranes isolated by CaCl 2 , the Na + -h + exchange was partially electroneutral (45% to 77% of the total exchange) and the rest was due to electrically coupled Na + and h + movements through conductive pathways in the membranes. In membranes prepared by MgCl 2 , the rate of total Na + -h + exchange was about twice as high as that in membranes obtained by CaCl 2 precipitation. however, total and electroneutral exchanges were equal indicating negligible electrically coupled Na + and h + movements in these membranes. K 0.5 for Na + in all preparations was in the same range, being in average 30 mM. Amiloride was a competitive inhibitor of Na + -h + exchange in membranes obtained with both preparations; K i values ranged between 0.1 and 0.58 mM. The rates of Δph-dissipation with K + gradients (±valinomycin) were by 50% to 150% higher in membranes prepared with CaCl 2 than in membranes isolated with MgCl 2 indicating much higher h + and K + conductances in membranes obtained with CaCl 2 . Therefore, the rate of Na + -h + exchange as well as the conductances for various ions in the isolated brush-border membranes depend on membrane preparation.

关键词： Na + -h + exchange Ion transport Acridine orange Brush-border membrane (Rat kidney cortex) EGTA ethyleneglycol bis(β-aminoethyl ether)- N , N ′-tetraacetic acid hepes N -2-hydroxyethylpiperazine- N ′-ethanesulfonic acid Mes N -morpholinoethanesulfonic acid PMSF phenylmethylsulfonyl fluoride TMA + tetramethylammonium

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REGULATION OF NA+-h+ EXChANGE BY TRANSMEThYLATION REACTIONS IN RAT COLONIC BRUSh-BORDER MEMBRANES

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BIOChIMICA ET BIOPhYSICA ACTA 1986年第1期859卷 61-68页

作者： DUDEJA, PK FOSTER, ES BRASITUS, TA MICHAEL REESE HOSP & MED CTR DEPT MED DIV GASTROENTEROL 31ST & LAKE SHORE DR CHICAGO IL 60616 USA

Incubation of rat colonic brush-border membrane vesicles with 200 .mu.M S-adenosyl-L-[Me-3h]methionine resulted in the labeling of both membrane phospholipids and proteins. This labeling was decreased approximately 50% by the methylation inhibitor S-adenosyl-L-homocysteine (2 mM). Utilizing the ph-sensitive fluorescenct dye, acridine orange, as a means of determining Na+-h+ exchange, S-adenosyl-L-methionine (200 .mu.M) significantly increased sodium-stimulated proton efflux in these vesicles at all concentrations of sodium (2.5-50 mM) tested. Examination of the kinetic parameters for sodium-stimulated proton efflux in the presence and absence of 200 .mu.M S-adenosyl-L-methionine revealed that the methyl donor increased the Vmax for this exchange mechanism (expressed in arbitrary fluorescence units) by approx. 36% but did not influence its Km for sodium. S-Adenosyl-L-homocysteine (2 mM) inhibited S-adenosyl-L-methionine-mediated stimulation of this exchange process. The results demonstrate that methylation of membrane phospholipids and/or proteins can modulate Na+-h+ exchange in rat colonic brush-border membrane vesicles.

关键词： Na + -h + exchange Transmethylation Phospholipid methylation Membrane protein methylation Brush-border membrane (Rat colon)

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ISOLATION OF RENAL BRUSh-BORDER MEMBRANE-VESICLES BY A LOW-SPEED CENTRIFUGATION - EFFECT OF SEX-hORMONES ON NA+-h+ EXChANGE IN RAT AND MOUSE KIDNEY

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BIOChIMICA ET BIOPhYSICA ACTA 1986年第1期862卷 141-152页

作者： MACKOVIC, M ZIMOLO, Z BURCKhARDT, G SABOLIC, I MAX PLANCK INST BIOPHYS KENNEDYALLEE 70 D-6000 FRANKFURT 70 FED REP GER UNIV ZAGREB FAC MED DEPT PHYSIOL YU-41001 ZAGREB YUGOSLAVIA

Na+-h+ exchange in rat and mouse renal brush-border membrane vesicles was studied by fluorescence quenching of the .DELTA. ph indicator, acridine orange. Brush-border membrane vesicles were isolated by a modified Mg/EGTA-precipitation method at low speed centrifugation (8000 .times. g). The enzymatic characteristics of these membrane vesicles were similar to those obtained by the original high-speed centrifugation method (Biber et al. (1981) Biochim. Biophys. Acta, 647, 169-176). The rates of Na+-h+ exchange in renal brush-border membrane vesicles from male and female rats were similar. Neither ovariectomy nor treatment of ovariectomized rats with estradiol or testosterone changed the activity of Na+-h+ exchanger. The rates of Na+-h+ exchange in the mouse were smaller than in the rat indicating the existence of species differences. Na+-h+ exchange in mouse renal brush-border membranes exhibit strong sex differences, the rates in the male being higher than in the female. Castration of male mice led to a decrease in Na+-h+ exchange to values found in females. Treatment of castrated mice with estradiol had no effect. In contrast, treatment with testosterone increased the rate of the exchanger by more than 100%. The effect of testosterone was restricted to the Vmax of the Na+-h+ exchanger, whereas the apparent Km for Na+ remained unchanged. Na+-dependent D-glucose transport in mouse renal luminal membranes exhibited also sex differences due to the potent stimulatory effect of testosterone. Therefore, Na+-h+ exchange and Na+-dependent D-glucose transport in the mouse kidney are under control of androgen hormones. This effect could be in close connection with the wellknown renotropic action of androgens in the mouse.

关键词： Na + -h + exchange Acridine orange Steroid hormone Membrane vesicle (Mouse kidney)

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