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Properties of a reaction-bonded β-SiAlON ceramic doped with an FeMo alloy for application to molten aluminum environments

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 530-536页

作者： Yan-jun Li Hai-liang Yu Hai-yun jin Zhong-qi Shi Guan-jun Qiao zhi-hao jin State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University School of Materials Science and Engineering Jiangsu University

An FeMo-alloy-doped β-SiA1ON （FeMo/β-SiA1ON） composite was fabricated via a reaction-bonding method using raw materials of Si, Al2O3, A1N, FeMo, and Sm2O3. The effects of FeMo on the microstructure and mechanical properties of the composite were investi- gated. Some properties of the composite, including its bending strength at 700℃ and after oxidization at 700℃ for 24 h in air, thermal shock resistance and corrosion resistance to molten aluminum, were also evaluated. The results show that the density, toughness, bending strength, and thermal shock resistance of the composite are obviously improved with the addition of an FeMo alloy. In addition, other properties of the composite such as its high-temperature strength and oxidized strength are also improved by the addition of FeMo alloy, and its corrosion re- sistance to molten aluminum is maintained. These findings indicate that the developed FeMo/β-SiA1ON composite exhibits strong potential for application to molten aluminum environments.

关键词： composite materials SiAION ceramics iron molybdenum alloys reaction bonding mechanical properties molten aluminum

Effect of 6H-SiC crystal growth shapes on thermo-elastic stress in the growing crystal

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 622-627页

作者： Yong-gui Shi Pei-yun Dai Jian-feng Yang zhi-hao jin Hu-lin Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China

The effect of 6H-SiC crystal growth shapes on the thermo-elastic stress distribution in the growing crystal was systematically in- vestigated by using a finite element method. The thermo-elastic stress distribution in the crystal with a flat growth shape was more homoge- neous than that in the crystals with concave and convex growth shapes, and the value of thermo-elasticity in the crystal with a fiat growth shape was also smaller than that in the two other types of crystals. The maximum values of thermo-elastic stress appeared at interfaces be- tween the crystal and the graphite lid. If the lid was of the same properties as 6H-SiC, the thermo-elastic stress would decrease in two orders of magnitude. Thus, to grow 6H-SiC single crystals of high quality, a transition layer of SiC formed by deposition or reaction is suggested; meanwhile the thermal field in the growth chamber should be adjusted to maintain the crystals with fiat growth shapes.

关键词： silicon carbide thermo-elasticity physical vapor transport single crystals crystal growth finite element method

金属钯插层类水滑石的制备及其电催化乙醇的性能研究

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电化学 2021年第1期27卷 100-107页

作者：胡守训李亮杨俊豪李刘强靳志豪上海理工大学环境与建筑学院上海200093

高性能的电催化剂对直接燃料电池的商业化应用有着至关重要的作用,目前的阳极材料还存在活性低、易中毒、成本高等问题。本研究以层状双氢氧化物(layered double hydroxides,LDHs)为载体通过浸渍法制备了新型纳米钯(Pd)催化剂,并通过X... 详细信息

高性能的电催化剂对直接燃料电池的商业化应用有着至关重要的作用,目前的阳极材料还存在活性低、易中毒、成本高等问题。本研究以层状双氢氧化物(layered double hydroxides,LDHs)为载体通过浸渍法制备了新型纳米钯(Pd)催化剂,并通过X射线衍射仪、扫描电子显微镜、电感耦合等离子体质谱仪、能谱仪、透射电子显微镜、循环伏安法测试、计时电流测试和电化学阻抗等方法对催化剂的结构和电催化性能进行了研究。结果表明,新制备的Pd/Mg-Al-LDHs仍然保持着LDHs的层状结构,循环伏安测试表明在碱性条件下,Pd/Mg-Al-LDHs比Pd/C有更好的电催化乙醇活性和抗中间产物中毒性能,且乙醇浓度、扫描速率和温度等因素对峰电流有着直接影响。计时电流测试表明在电催化乙醇的过程中Pd/Mg-Al-LDHs比Pd/C拥有更高的电催化活性和稳定性。电化学阻抗测试表明,Pd插层可显著改善Mg-Al-LDHs的导电性,并降低电催化过程中电荷转移阻力。

关键词：金属钯电催化阳极催化剂层状双氢氧化物直接乙醇燃料电池

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一个基于对象、域和型的层次式程序表示模型

计算机科学 2003年第4期30卷 118-120,135页

作者：赵洋蔡志旻金浩潘金贵南京大学计算机软件新技术国家重点实验室

It is necessary to represent a program in a visual model before analyzing it. This paper introduces a hierarchical program visual model based on object, scope and type. It depicts a program's information through a recursive-nested structure. Particularly, it emphasizes on the inherent relationships among objects, scopes and types and connects objects and types within scopes. This paper explains all parts and their relationships in details and also addresses briefly about how to realize the model.

关键词：程序设计语言符号语言程序员层次式程序表示模型类型对象作用域程序设计

不同时间窗电针对急性局灶性脑缺血模型大鼠脑组织活性钙调素含量影响的研究

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针刺研究 2003年第3期28卷 178-181页

作者：金智秀郝晋东卢峻图娅北京中医药大学针灸学院北京100029

目的 :研究不同时间窗电针对实验性脑缺血疗效的影响。方法 :采用光化学法诱导局灶性脑缺血模型 ,于造模成功后 0 5hr、1hr、3hr、6hr、1 2hr五个不同的时间窗开始电针 ,比较治疗 6天后急性局灶性脑缺血模型大鼠脑组织活性钙调素 (CaM... 详细信息

目的 :研究不同时间窗电针对实验性脑缺血疗效的影响。方法 :采用光化学法诱导局灶性脑缺血模型 ,于造模成功后 0 5hr、1hr、3hr、6hr、1 2hr五个不同的时间窗开始电针 ,比较治疗 6天后急性局灶性脑缺血模型大鼠脑组织活性钙调素 (CaM)含量的变化。结果 :大鼠脑缺血后 ,模型组CaM的含量明显升高 ,与空白对照组和假手术组相比有显著性差异 (P 0 0 5) ,但超早期不同的时间窗电针组间差异不显著 (P >0 0 5)。结论 :针刺疗法超早期介入在大鼠局灶性脑缺血中发挥肯定的脑保护作用 ,但从造模后 0

关键词：电针急性局灶性脑缺血脑组织活性钙调素含量影响研究治疗时间窗

A mechanical reinforced and antifreezing polyacrylate hydrogel electrolyte for high-performance zinc-ion batteries

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Nano Research 2025年第1期18卷 341-350页

作者： Zili Zhang Ruolin Wang Hongfei Lu Di Zhang Yu Zhao jing Xu Bin Sun zhi-Min Dang Yang jin School of Electrical and Information Engineering Zheng Zhou UniversityZhengzhou 450001China State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The operation of aqueous zinc-ion batteries in flexible energy storage field is plagued by the uncontrollable growth of Zn-dendrite and inevitable freeze of water below 0 ℃.Therefore,it is necessary to design a hydrogel electrolyte with good mechanical property and freezing resistance to uniform the Zn-deposition and resist flexibility loss at low *** find that the mechanical property(strength and toughness)of hydrogel electrolyte has a significant impact on the suppression of dendrite growth and the uniform deposition of zinc ***,a polyacrylate hydrogel is prepared in one step by ultraviolet(UV)curing method with Zn(CF_(3)SO_(3))_(2)salt and polyvinyl alcohol(PVA)addition to increase the antifreezing ability and mechanical *** adsorption of water molecules by 2-hydroxyethyl acrylate(HEA)and PVA reduces the freezing point of the hydrogel,which is beneficial for enhancing the electrochemical stability at low *** this basis,the Zn-symmetrical battery with hydrogel electrolyte has a long lifespan of 4710 h at 0.5 mA·cm^(-2)and 0.5 mAh·cm^(-2)at room ***,the hydrogel electrolyte exhibits an outstanding stability at low temperature of^(-2)0 ℃,the lifespan of symmetrical battery reaches to 4000 h at 0.5 mA·cm^(-2)and 0.5 mAh·cm^(-2).The assembled full cell with NaV3O8·1.5H_(2)O(NVO)cathode and hydrogel electrolyte possesses a high capacity retention ratio of 77%after 10,000 cycles at^(-2)0 ℃.The flexible cell can power light-emitting diode(LED)lamp under bending,warping and cutting without liquid leakage and an electronic watch at the operating temperature of^(-2)0 ℃.

关键词： zinc ion battery hydrogel electrolyte mechanical enhancement freezing resistance

Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy

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World Journal of Gastroenterology 2025年第1期31卷 110-125页

作者： Xin Zhou Dan Ma Yi-Xiang He jing jin Hong-Lian Wang Yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen zhi Li Department of Spleen and Stomach Diseases the Affiliated Traditional Chinese Medicine HospitalSouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina The Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Digestive System Diseases of Luzhou City The Affiliated Traditional Medicine HospitalSouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Gastroenterology Changhai HospitalNaval Medical UniversityShanghai 20082China Research Center of Integrated Chinese and Western Medicine The Affiliated Traditional Chinese Medicine HospitalSouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina School of Integrated Traditional Chinese and Western Clinical Medicine North Sichuan Medical CollegeNanchong637100Sichuan ProvinceChina

BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after *** To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus *** Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential *** examinations occurred on days 7 and 21 *** vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was *** signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after *** treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal ***,the expression of fibrotic effector molecules was notably ***,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/*** vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen *** 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated *** KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway.

关键词： Kangfuxin solution Natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis

SZD10-245/400型抛煤机链条锅炉技术改造

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热能动力工程 2000年第6期15卷 687-687,702页

作者：郝志金王擎孙冬红姜秀民李学恒孙健隋凤林东北电力学院吉林省吉林市132012 哈尔滨工业大学鞍钢房产建安公司

分析了抛煤机链条锅炉运行中存在的问题 ,提出了用复合循环燃烧技术把抛煤机链条锅炉改造成循环流化床锅炉的措施。运行结果表明 ,改造后的锅炉达到了预期效果。

关键词：抛煤机链条锅炉复合循环燃烧循环流化床锅炉

Comparison of different techniques for time-frequency analysis of internal combustion engine vibration signals

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 519-531页

作者： Yang jin zhi-yong hao Xu ZHENG Department of Energy Engineering Zhejiang University Hangzhou 310027 China Department of Automotive Engineering Hubei University of Automotive Technology Shiyan 442002 China

In this study,we report an analysis of cylinder head vibration signals at a steady engine speed using short-time Fourier transform(STFT).Three popular time-frequency analysis techniques,i.e.,STFT,analytic wavelet transform(AWT) and S transform(ST),have been *** and ST are often applied in engine signal *** particular,an AWT expression in terms of the quality factor Q and an analytical relationship between ST and AWT have been *** time-frequency resolution of a Gaussian function windowed STFT was studied via numerical *** on the simulation,the empirical limits for the lowest distinguishable frequency as well as the time and frequency resolutions were *** can provide insights for window width selection,spectrogram interpretation and artifact *** function windowed STFTs were applied to some cylinder head vibration *** spectrograms of the same signals from ST and AWT were also determined for *** results indicate that the uniform resolution feature of STFT is not necessarily a disadvantage for time-frequency analysis of vibration signals when the engine is in stationary state because it can more accurately localize the frequency components excited by transient excitations without much loss of time resolution.

关键词： Short-time Fourier transform(STFT) Gaussian window Time-frequency resolution limits Internal combustion(IC) engine Vibration signals Analytic wavelet transform(AWT) S transform(ST)