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Li_2B_4O_7晶体的比热、导温和导热性能 被引量:3
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作者 徐一斌 奚同庚 +4 位作者 倪鹤林 段炼 李明华 蔡忠龙 费扬 《材料研究学报》 EI CAS CSCD 1994年第5期445-448,共4页
用DSC和激光热导仪分别测定了Li2B4O7(LBO)晶体350—970K范围内的比热和630—970K范围内不同主晶轴方向的导温系数.并由此得出了导热系数和声子平均自由程.
关键词 Li2B4O7晶体 比热 导温
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掺聚丙烯纤维高强混凝土高温后导温性能研究 被引量:4
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作者 王飞剑 张琦 +1 位作者 杜红秀 阎蕊珍 《混凝土与水泥制品》 北大核心 2014年第12期56-59,共4页
分别对掺聚丙烯纤维高强混凝土和素高强混凝土高温后导热系数、表观密度进行了试验研究,分析了两者的表观密度、导热系数和导温系数的变化规律,结果表明,高温后掺聚丙烯纤维高强混凝土和素混凝土的表观密度、导热系数均呈下降趋势,高温... 分别对掺聚丙烯纤维高强混凝土和素高强混凝土高温后导热系数、表观密度进行了试验研究,分析了两者的表观密度、导热系数和导温系数的变化规律,结果表明,高温后掺聚丙烯纤维高强混凝土和素混凝土的表观密度、导热系数均呈下降趋势,高温前后掺聚丙烯纤维高强混凝土比素高强混凝土的表观密度小、导热系数和导温系数大,而且其导热系数和导温系数随温度变化规律更为明显。 展开更多
关键词 聚丙烯纤维 高强混凝土 导温性能
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同时测定生物组织热物性参数(比热导热系数和导温系数)的实验方法
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作者 郑金宝 颜波 《低温工程》 CAS CSCD 1991年第4期44-50,共7页
关键词 生物材料 热特性 测量 传热 导温
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以温肾导督为治则综合治疗类风湿性关节炎八十九例 被引量:1
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作者 苏云放 《浙江中医杂志》 北大核心 1994年第8期373-374,共2页
以温肾导督为治则综合治疗类风湿性关节炎八十九例310009浙江中医学院苏云放笔者从1989年以来,以温肾导督法为治则,运用内服汤药、外施膏摩等法,治疗类风湿性关节炎89例,疗效良好。现介绍如下。一般资料89例中男32... 以温肾导督为治则综合治疗类风湿性关节炎八十九例310009浙江中医学院苏云放笔者从1989年以来,以温肾导督法为治则,运用内服汤药、外施膏摩等法,治疗类风湿性关节炎89例,疗效良好。现介绍如下。一般资料89例中男32例,女57例;年龄最小23岁,最大... 展开更多
关键词 类风湿性 关节炎 督法
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海表浅层水体温度剖面测量设备研发与实现
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作者 徐学范 张凯临 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第8期93-103,共11页
海表水体温度是海洋的一个重要特征,为了得到海表浅层水体即海面以下0~10 m深度范围内水体的垂直温度剖面,本文设计了一种基于红外测温原理的接触式测量方式的海表浅层水体温度剖面测量设备。该设备使用红外热像仪测量与水体接触的导温... 海表水体温度是海洋的一个重要特征,为了得到海表浅层水体即海面以下0~10 m深度范围内水体的垂直温度剖面,本文设计了一种基于红外测温原理的接触式测量方式的海表浅层水体温度剖面测量设备。该设备使用红外热像仪测量与水体接触的导温片的温度来间接得到海水温度,并通过排布较为密集的导温片得到垂直分辨率较小的水体温度剖面,最小测温点间距可达2 cm。设备内部使用了校正黑体进行实时校正,得到较为精确的导温片温度。设备在实验室进行了黑体定标实验及实验室水槽模拟实验,测温精度可达±0.1℃。实验结果表明,该设备测量水体温度具有较好精度,且容易部署,可得到测量范围内海水垂直分辨率较小的温度剖面。该设备在一定程度上可以提高海水温度剖面垂直分辨率,可以为卫星观测海温的误差修正提供实地测量参考。 展开更多
关键词 海表水体度剖面 红外热像仪 导温 实时校正 黑体
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缝内含有不同导温介质时的稳定温度断裂研究
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作者 刘光廷 张国新 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 1990年第2期15-21,共7页
针对水工砼工程实际中常常遇到张开型裂缝或缝内含有与砼和岩石不同导热介 质的材料,引入等效热导率,以确定热断裂解,即求解含缝体的温度场、应力场或应力强 度因子。等效热导率可用两块平行板,中间有不同厚度的间隔或不同的导热介... 针对水工砼工程实际中常常遇到张开型裂缝或缝内含有与砼和岩石不同导热介 质的材料,引入等效热导率,以确定热断裂解,即求解含缝体的温度场、应力场或应力强 度因子。等效热导率可用两块平行板,中间有不同厚度的间隔或不同的导热介质时的实 验量测而得。解析结果和实验结果吻合良好。对某实际工程的计算结果表明,由充满导 热介质的裂缝干扰稳定温度场而引起的应力强度因子远小于裂缝面绝热假定引起的应力 强度因子值。 展开更多
关键词 水工结构 砼水工结构 裂缝 度场 导温介质
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水轮发电机组下导轴承瓦温偏高的处理 被引量:2
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作者 张志勇 《机电信息》 2018年第12期66-67,共2页
结合三板溪水电厂4号机组下导轴承瓦温偏高的现象,对立式水轮发电机组下导轴承瓦温偏高的原因进行了分析。认为在导轴承测温系统运行正常、技术供水压力参数与其他机组无异、供水管路正常等情况下,机组下导瓦温逐年升高,并最终越限报警... 结合三板溪水电厂4号机组下导轴承瓦温偏高的现象,对立式水轮发电机组下导轴承瓦温偏高的原因进行了分析。认为在导轴承测温系统运行正常、技术供水压力参数与其他机组无异、供水管路正常等情况下,机组下导瓦温逐年升高,并最终越限报警,是由于导轴承间隙调整、轴瓦表面加工质量及投产运行磨损影响导致。因此提出了针对性处理方法,并进行了详细分析论述,最终解决了瓦温偏高的问题。 展开更多
关键词 水轮发电机 轴承瓦 偏高处理
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中职化学教学中的导课艺术
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作者 车光兰 《中国市场》 2015年第27期297-298,共2页
文章从联系已知,温故导新;聚焦生活,顺势导入;设置矛盾,质疑导入;激情启趣,因势导入;设疑布阵,造成悬念;补充材料,搭桥铺路;演示实验,直观导入七个方面阐述了在课堂教学中恰当运用导课艺术,激发学生的学习兴趣,提高教学效果。
关键词 质疑 因势 造成悬念 搭桥铺路
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语文教学中的导课艺术
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作者 李丽英 《西部素质教育》 2019年第19期238-238,共1页
为了提高语文教学的效率和质量,激发学生的学习兴趣,文章从温故导课、问题导课、故事导课、悬念导课、释题导课、歌曲导课、谜语导课等七方面论述了语文教学中的导课艺术。
关键词 语文教学 课艺术 问题
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D类功放中输入斩波运放电路的设计 被引量:3
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作者 赵海亮 刘诺 周长胜 《半导体技术》 CAS CSCD 北大核心 2008年第6期520-523,538,共5页
基于n阱0.5μmDPDMCMOS工艺,完成了D类音频功放中输入斩波运算放大器的设计。分析了D类系统对输入运放的设计要求,在此基础上确定了电路采用两级全差分结构实现,并加入斩波结构降低噪声。采用PTAT电流源提供运放的偏置电流,补偿运放跨... 基于n阱0.5μmDPDMCMOS工艺,完成了D类音频功放中输入斩波运算放大器的设计。分析了D类系统对输入运放的设计要求,在此基础上确定了电路采用两级全差分结构实现,并加入斩波结构降低噪声。采用PTAT电流源提供运放的偏置电流,补偿运放跨导gm的温度漂移。在Cadence下的电路仿真表明,前级运放具有16μV.Hz-1/2的等效输入噪声,开环增益达到117.3 dB。运放所在芯片经过PWM方式流片验证,测试结果显示,芯片THD达到0.58%(f=1 kHz、Po=1 W、VDD=5 V),电源抑制比为65 dB。 展开更多
关键词 D类功放 斩波 输入运放 导温
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Catalytic performance of biological method seeds on jarosite process 被引量:4
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作者 李海军 杨洪英 陈国宝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第2期557-564,共8页
The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smo... The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smooth surface and mainly consisted of potassium jarosite. The chemical synthesis jarosite seeds (CHM seeds) had a loose cauliflower-like surface and mainly consisted of hydronium jarosite. The catalytic performance of BIO seeds was better than that of CHM seeds on the formation of final jarosite product. The induction time can be shortened to 20 min, the reaction temperature can be reduced to only 75 ℃, and the initial reaction speed was enhanced obviously, up to 3.933%/min. The crystallinity of final jarosite product using BIO seeds can achieve 97.22%, while it was only 12.89% without seeds. This indicates that the precipitation process of jarosite is more complete with BIO seeds. 展开更多
关键词 jarosite seed jarosite process induction period temperature initial precipitate rate
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Establishment of Reverse-transcription Loopmediated Isothermal Amplification Method for Detection of Wheat Streak Mosaic Virus 被引量:4
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作者 徐颖 《Agricultural Science & Technology》 CAS 2014年第11期1857-1859,1941,共4页
A reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method was established for the detection of wheat streak mosaic virus (WSMV). Ac-cording to the conservative regions of the genes that encod... A reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method was established for the detection of wheat streak mosaic virus (WSMV). Ac-cording to the conservative regions of the genes that encode the coat protein of WSMV, 2 pairs of primers were designed. Final y, the 1st pair of primers was select-ed through the specificity test. The sensitivity test showed the sensitivity of RT-LAMP method was 10 times higher than that of RT-PCR. In addition, the amplifica-tion of target gene could be judged visual y from the presence of fluorescence (cal-cein) in the final reaction system. The RT-LAMP method, established in this study, was rapid, easy, specific and sensitive. Moreover, it did not require sophisticated equip-ment. The RT-LAMP was suitable for the rapid detection of WSMV. 展开更多
关键词 Wheat streak mosaic virus (WSMV) Reverse-transcription loop-mediated isothermal amplification (RT-LAMP) Detection method
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The theoretical expressions of wood thermal diffusivity
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作者 杨庆贤 杨绮 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期133-135,共3页
From viewpoint of chemical element and microstructure of wood, this paper makes a discussion on thermal diffusivity of wood and two theoretical expressions of thermal diffusivity for the choral and radial directions w... From viewpoint of chemical element and microstructure of wood, this paper makes a discussion on thermal diffusivity of wood and two theoretical expressions of thermal diffusivity for the choral and radial directions were derived. The thermal diffusivities of the choral and radial directions for about 20 species of trees were calculated with the derived theoretical expressions and compared with the experimental values. The average error of the theoretical values of thermal diffusivity was 7.5% for choral direction and 6.2% for radial direction. 展开更多
关键词 Thermal diffusivity Theoretical expression WOOD
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Isolation and Characterization of a BBC1 cDNA from Common Wheat
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作者 常胜合 英加 +2 位作者 张吉军 李滨 李振声 《Acta Botanica Sinica》 CSCD 2003年第7期878-882,共5页
A breast basic conserved 1 (BBC1) cDNA has been isolated from common wheat (Triticum aestivum L.). Analysis of amino acid sequence derived from the cDNA showed that the wheat BBC1 was highly hydrophilic and rich in al... A breast basic conserved 1 (BBC1) cDNA has been isolated from common wheat (Triticum aestivum L.). Analysis of amino acid sequence derived from the cDNA showed that the wheat BBC1 was highly hydrophilic and rich in alanine, lysine, glutamic acid and arginine residues. The transcription of wheat BBC1 mRNA was regulated by low temperature. Southern blotting analysis showed that BBC1 existed as a small family in common wheat genome. 展开更多
关键词 breast basic conserved I (BBC1) cold induction common wheat
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The Application of Reverse Transcription-loop-mediated Isothermal Amplification for the Rapid Detection of Maize Chlorotic Dwarf Virus
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作者 徐颖 张峰 +1 位作者 于莹 邱志君 《Agricultural Science & Technology》 CAS 2017年第12期2450-2453,共4页
Maize chlorotic dwarf virus (MCDV) is a quarantine pest as approved by Chinese government. A rapid, sensitive and specific MCDV detection method using reverse transcription-loop-mediated isothermal amplification (R... Maize chlorotic dwarf virus (MCDV) is a quarantine pest as approved by Chinese government. A rapid, sensitive and specific MCDV detection method using reverse transcription-loop-mediated isothermal amplification (RT-LAMP) was estab- lished in this study. Based on the sequence of MCDV coat protein coding gene, specific primers were designed and similar sensitivities were observed between RT- LAMP and RT-PCR, except that RT-LAMP was quicker, and the reaction could be finished within 1 h. In addition, the presence or absence of the fluorescent display in daylight allows naked easy detection of the amplification of MCDV genomic RNA using calcein. The RT-LAMP assay was applied successfully to detect MCDV in maize seeds, and the result by the addition of calcein was consistent with the result detected by the real time turbidimeter. 展开更多
关键词 Maize chlorotic dwarf virus (MCDV) Reverse transcription loop-mediatedisothermal amplification (RT-LAMP) Rapid detection
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NUMERICAL SIMULATIONS OF TEMPERATURE FIELD IN DIRECT METAL LASER SINTERING PROCESS 被引量:6
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作者 顾冬冬 沈以赴 +2 位作者 刘满仓 潘琰峰 胥橙庭 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期225-233,共9页
A mathematical model is developed for simulating the heat transferring behavior in a direct metal laser sintering process. The model considers the thermal phenomena involved in the process, including conduction, radia... A mathematical model is developed for simulating the heat transferring behavior in a direct metal laser sintering process. The model considers the thermal phenomena involved in the process, including conduction, radiation, and convection. A formula for the calculation of the heat conductivity of a sintering system containing solid phase, liquid phase, and gas phase is given. Due to the continuous movement of the laser beam, a local coordinate system centered on the laser beam is used to simplify the analytical calculation. Assuming that it is approximately a Gaussian laser beam, the heat conduction equation is resolved based on the assumption of the thermal insulating boundary conditions and the fixed thermal physical parameters. The FORTRAN language is employed to compile the program to simulate the temperature field in the direct copper powder sintering process. It shows a good agreement with the preliminary experimental results.[KH3/4D] 展开更多
关键词 direct metal laser sintering (DMLS) mathematical model temperature field numerical simulation
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Metabolism and thermoregulation between Mrs Hume's Pheasant(Syrmaticus humiae) and Elliot's Pheasant(S.ellioti) 被引量:6
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作者 骆鹰 庾太林 +3 位作者 黄乘明 赵彤 李汉华 李常健 《Zoological Research》 CAS CSCD 北大核心 2011年第4期396-402,共7页
To understand metabolic adaptations,the basal metabolic rate(BMR) of Mrs Hume's Pheasant(Syrmaticus humiae) and Elliot's Pheasant(Syrmaticus ellioti) were investigated.Metabolic rate(MR),body temperature(Tb... To understand metabolic adaptations,the basal metabolic rate(BMR) of Mrs Hume's Pheasant(Syrmaticus humiae) and Elliot's Pheasant(Syrmaticus ellioti) were investigated.Metabolic rate(MR),body temperature(Tb) and thermal conductance(C) were determined in both species at a temperatrue range of 5-35 ℃,respectively.Oxygen consumption was measured with a closed circuit respirometer.The thermal neutral zones(TNZ) were 24.5-31.6 ℃,and 23.0-29.2 ℃,respectively.With a temperature range of 5-35 ℃,Mrs Hume's Pheasant and Elliot's Pheasant could maintained stable Tb at a mean of(40.47±0.64) and(40.36±0.10) ℃,respectively.Mean BMRs within TNZs were(1.36±0.84) mLO2/(g.h) for Mrs Hume's Pheasant and(2.03±0.12) mLO2/(g.h) for Elliot's Pheasant,which were 77% and 86% of the expected value based on their body mass,respectively.Thermal conductance of Mrs Hume's Pheasant and Elliot's Pheasant were(0.12±0.01) and(0.17±0.01) mLO2/(g.h.℃),below the lower critical temperature,respectively,which were 119% and 124% of the expected value based on their body mass,respectively.The ecophysiological characteristics of these species were low metabolic rate,high body temperature,and high thermal conductance,which allow both species to better adapt to the warmer climate environment in south China. 展开更多
关键词 Syrmaticus humiae Syrmaticus ellioti Body temperature Basal metabolic rate Thermal conductance
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1.3μm AlInGaAs Strained Single Quantum Well Laser Diodes with High Characteristic Temperature of 200K 被引量:1
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作者 王玉霞 刘春玲 +3 位作者 芦鹏 王勇 曲轶 刘国军 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1912-1915,共4页
A high characteristic temperature (T0) of 200K from a 1.3μm AlInGaAs/AlInAs single-quantum-well laser diode with the asymmetric waveguide layer structure under CW operation at 20 to 80℃ was obtained,which is the b... A high characteristic temperature (T0) of 200K from a 1.3μm AlInGaAs/AlInAs single-quantum-well laser diode with the asymmetric waveguide layer structure under CW operation at 20 to 80℃ was obtained,which is the best result reported in the laser diodes (LDs) of the same active materials structure and emitting wave- length. AllnGaAs as an active layer,therefore,is very promising for the fabrication of long-wavelength LDs with excellent high-temperature performance. It is found that the asymmetric waveguide layer structure can decrease optical absorption and improve the high-temperature performance and catastrophic optical damage threshold of LDs. 展开更多
关键词 semiconductor LDs AllnGaAs characteristic temperature threshold current asymmetricwaveguide layer
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CLINICAL AND ELECTROPHYSIOLOGICAL OBSERVATIONS ON DIABETIC PERIPHERAL NEUROPATHYTREATED BY WARM NEEDLING AND MOXIBUSTION 被引量:4
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作者 孙远征 徐莺莺 吴迪 《World Journal of Acupuncture-Moxibustion》 2008年第2期1-6,共6页
Objective To observe clinical therapeutic effects of warm needling and moxibustion on diabetic peripheral neuropathy (DPN) and their influence on nerve conduction velocity. Methods Fifty two cases were randomly divi... Objective To observe clinical therapeutic effects of warm needling and moxibustion on diabetic peripheral neuropathy (DPN) and their influence on nerve conduction velocity. Methods Fifty two cases were randomly divided into a treatment group (n =26) and a control group (n =26). In addition to basic treatment for lowering blood sugar in both groups, Pǐshū (BL 20), Shènshū (BL 23), Huántiào (GB 30), Zùsānlǐ (ST 36), Yánglíngquán (GB 34), Sānyīnjiāo (SP 6), Tàixī (KI 3), Qǔchí (LI 11), Wàiguān (TE 5) and Hégǔ (LI 4) were selected for warm needling and moxibustion in the treatment group. Methycobal was intramuscularly injected in the control group. Clinical symptoms and conduction velocities of the tibial nerve and common peroneal nerve were compared before and after treatment. Results Warm needling and moxibustion could alleviate such clinical symptoms as numbness of limbs, pain and hypoesthesia, and obviously improve the conduction velocities of both tibial and common peroneal nerves. Conclusion Warm needling and moxibustion exhibit good therapeutic effects on diabetic peripheral neuropathy. 展开更多
关键词 Diabetic Peripheral Neuropathy Warm Needling and Moxibustion Nerve Conduction Velocity
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Preparation of (SiFe) C DMS Based 4H-SiC Substrate
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作者 姜岩峰 王建平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1436-1440,共5页
A diluted magnetic 4H-SiC has been prepared by implanting Fe ions into the substrate. Its Curie temperature reaches as high as 320K and its technology is compatible with current IC. Moreover, the process includes thre... A diluted magnetic 4H-SiC has been prepared by implanting Fe ions into the substrate. Its Curie temperature reaches as high as 320K and its technology is compatible with current IC. Moreover, the process includes three annealing steps,named HNH annealing in this paper. Each step during this annealing has been analyzed. Comparisons have been made with different Fe concentrations and experimental results demonstrate that when the concentration of Fe is 0. 051, the Curie temperature is the highest. According to measurements, some explanation of this phenomenon is given. 展开更多
关键词 SPINTRONICS diluted magnetic semiconductor ANNEALING Curie temperature
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