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31.
可以图形化和沉积同时进行的镀膜技术可有效简化器件制备流程, 从而降低成本。本工作研究了一种新型的图形化沉积镀膜技术-微流控法: 将宽度及间隔均为80 μm、沟槽深度为2 μm左右的PDMS模板与衬底贴合构筑微流通道, 毛细力作用下前驱液可在微流通道内流动, 并在衬底表面形成图形化的液膜, 最后经热处理完成图行化的薄膜沉积。此外, 分析了硝酸镍/2-甲氧基乙醇前驱体的热分解过程和不同温度退火下前驱体粉末的相结构演化规律。最终利用微流控法图形化沉积技术制备了图形化的氧化镍沟道, 并构筑了薄膜晶体管器件。优化后的薄膜晶体管表现出典型的p型特征, 场效应迁移率可达0.8 cm2·V-1·s-1。  相似文献   
32.
The processing and reaction mechanism of metallic aluminum (Al) powder as an active filler that controls polycarbosilane (PCS) precursor pyrolysis are investigated. Since Al can react with N2 to produce aluminum nitride (AlN), the linear shrinkage upon pyrolysis decreases and the ceramic yield of PCS increases. The linear shrinkage is zero when the volume ratio between Al and PCS, νAl/PCS, is about 56%. Aluminum also enhances the three-point bending strength of the ceramics with a flexural strength of 212 MPa when νAl/PCS is 60%. The relationship among pyrolysis temperature, T p, linear shrinkage and flexural strength of the derived ceramics has been investigated. The results showed that, for the Al-containing PCS-derived ceramics, a linear expansion occurred as the flexural strength was enhanced when T p increased from 400 to 1000°C. The reaction mechanism of Al-controlled PCS pyrolysis was investigated by thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), and elemental line-scanning electron microscopy (ELSEM). The results showed that the SiC powder took on the role of a catalyst, which decreased the nitridation temperature of aluminum and increased the conversion yield from Al to AlN. An erratum to this article can be found at  相似文献   
33.
采用热重-差热(TG-DTA)与气-质联用(GC-MS)研究了CVD技术制备钯膜材料的前驱体乙酰丙酮钯[Pd(acac)2]的热分解行为。通过对比其在空气和氩气两种气氛、不同温度下的热裂解产物,认为在以乙酰丙酮钯为前驱体通过CVD技术制备钯膜时,空气比氩气更适合做载气。  相似文献   
34.
The decomposition process for zircon sand concentrate using mixed base of sodium hydroxide partly replaced by calcium oxide was inrestigated.It is found that the decomposition rate of zircon gradually increased with the increase of the reaction temperature and time.The decomposition rate is over 97% with the conditions that CaO/zircon molar ratio is 0.25 ~ 0.75 at 800 ℃ for 1 h.Whereas the decomposition rate decreased when the molar ratio was more than 0.75.Also,thermogravimetry-differential thermal analysis(TG-DTA) and X-ray diffraction(XRD) were used to study the reaction mechanism of zircon decomposition process with CaO-NaOH.The results showed that Na2O,which was generated by the reaction of CaO and Na4SiO4,increased the decomposition rate of zircon owing to its spread to the surface of zircon and played a role in decomposition process.  相似文献   
35.
用于复合型薄膜电极的TiO2-ZnO复合溶胶的研究   总被引:1,自引:0,他引:1  
为了制备TiO2-ZnO复合型薄膜电极,本研究采用了不同Ti/Zn摩尔比,探讨TiO2与ZnO溶胶混合方法对TiO2-ZnO复合型薄膜结构与性能的影响.溶胶制备方法为溶胶-凝胶法( sol-gel),两种复合溶胶的Ti/Zn摩尔比为3∶1及1∶1.对两种混合溶胶分别进行了差热-热重分析(TG-DTA)及XRD分析.测试结果表明:Ti/Zn(摩尔比)=3∶1复合溶胶的差热-热重曲线在370℃和415℃两个温度点出现较为明显的放热峰.对应XRD分析中也显示热处理后的溶胶中出现了锐钛矿和偏钛酸锌这两种晶相,Ti/Zn(摩尔比)=1∶1复合溶胶的差热-热重曲线仅在450℃出现一个明显放热峰,其对应XRD分析显示,在各个热处理温度下,该复合溶胶仅含有唯一晶相偏钛酸锌.两种混合溶胶测试分析表明,以直接混合TiO2及ZnO溶胶的方式,薄膜中将会出现偏钛酸锌,偏钛酸锌具有高介电常数,即具有较低的绝缘性能和较高的导电性能,用于半导体薄膜中可能会有益于光电性能的提高.本文还采用Ti/Zn(摩尔比)=3∶1混合溶胶在未腐蚀和已腐蚀玻璃载体上进行了镀膜实验,对热处理后的样品进行了表面及断面的SEM研究,发现采用分步热处理方式,可以得到较为理想的薄膜,基体腐蚀与否对薄膜和基体的结合性甚微.  相似文献   
36.
Thermal degradation characteristics of a Japanese oil sand at different heating rates (10, 20, and 30 °C/min), and 30 ml/min air flow rate have been investigated. The kinetic parameters have been calculated based on three stages of weight loss and/or the conversion of the sample. These include, stage 1 (SI): volatilization of moisture content and the light hydrocarbon (20–227 °C), stage 2 (SII): combustion of heavy hydrocarbon (227–527 °C), and stage 3 (SIII): oxidative decomposition of carbonaceous organic matter (502–877 °C). The results showed that the rate of change of the oil sand conversion with time dαdt was affected by the heating rate. The time taken by the system to reach 0.99 conversion was observed as 85, 50, and 35 min at the heating rates of 10, 20, and 30 °C/min, respectively. The frequency factor, A, at SI was between 0.09 and 0.54 min?1, while the activation energy, Ea, was 11.2–12.5 KJmol?1 (the percentage weight loss, Wt, was 0–3.6 %w/w; and the conversion, α, was 0–0.2.). At SII, the values of A and Ea were 2.1–5.5 min?1 and 17.6–19 KJmol?1, respectively (Wt = 3.1–15.88 %w/w; α = 0.17–0.86.). The value of A at SIII was 5.5E11–1.1E13 min?1, while Ea was 160–200 KJmol?1 (Wt = 15.33–17.99 %w/w; and α = 0.84–0.99).  相似文献   
37.
一种新型短切碳纤维增强纸基摩擦材料研究   总被引:6,自引:0,他引:6  
以短切碳纤维为增强纤维,采用湿法工艺研制成功一种新型无石棉纸基摩擦材料,采用TG-DTA热分析方法、定速摩擦试验和惯量摩擦研究了摩擦材料耐热性能、摩擦性能和磨损性能.试验结果表明,新研制的炭纤维增强纸基摩擦材料的起始分解温度和失重速率等耐热性能指标优良,动摩擦系数高达0.136~0.149,且摩擦系数稳定,磨损率低,是一种理想的新型无石棉纸基摩擦材料.  相似文献   
38.
Structural properties of the 2,4,6-triaminopyridinium dihydrogendiphosphate dihydrate are discussed on the basis of an X-ray structure investigation. (C4H8N5)2H2P2O7·2H2O is monoclinic, C2/c, with a = 10.414(1) Å, b = 13.365(1) Å, c = 13.736(2) Å, β = 98.39(4)°, and Z = 4. The structure has been solved by a direct method and refined to a reliability R factor of 0.0375 (Rw = 0.0961) using 2751 independent reflections. The structural arrangement can be described as inorganic infinite ribbons, , spreading along the c direction; the organic groups, [C4H8N5]+, link the precedent ribbons, via their hydrogen bonds, to form a three-dimensional network. The present work, deals with crystal structure, thermal behavior and IR analysis of this new compound.  相似文献   
39.
合成了一种用作前驱体的,具有八面体结构新型水溶性的金属复合离子型化合物碳酸二羟基.四氨合铂(IV)二水合物([Pt(NH3)4(OH)2]CO3.2H2O),用元素分析和X射线单晶衍射仪(XRD)对其结构进行了表征,用热重-差热(TG-TDA)测试其热分解特性,并对比评价制备DOC催化剂的性能。结果表明,化合物为单斜晶系、P21/c空间群,晶胞参数为:a=0.88191(14) nm,b=1.17817(18) nm,c=1.01533(16) nm,V=0.9978(3) nm3,Z=4,R1=0.0403,wR2=0.1235,R1=0.0466,wR2=0.1353。其晶体结构为以Pt(IV)为中心与4个NH3和2个羟基配位形成八面体的二价阳离子;TG-DTA测试显示化合物分解峰出现在223.8℃;制备得到的DOC催化剂催化活性和起燃温度优于传统前驱体化合物。  相似文献   
40.
采用热重-差热法测定了1-L-苯丙氨酸-l-脱氧-D-果糖(PDF)的热失重和热裂解温度,在线裂解GC/MS联用技术鉴定了PDF在350,450,550,650,750和850℃下的裂解产物.结果表明,PDF的初始裂解温度为145.91℃,二次裂解温度为170.70℃,500 ℃时裂解物失重约80%;裂解产物主要为芳烃类和杂环化合物类;裂解产物的数量随着裂解温度的升高而增多,尤其是芳香族化合物类.  相似文献   
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