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1.
Coordination compounds of thiourea with cadmium(II), zinc(II), bismuth(III), and indium(III) nitrates were synthesized. The self-sustained combustion of these complexes, as well as that of thiosemicarbazide coordination compounds of nickel(II), cobalt(II), iron(II), copper(II), lead(II), and zinc(II) nitrates, was studied in an inert atmosphere. All these compounds burn to yield metal sulfides. The particle size and morphology of the product depend on the pressure at which the process is carried out. For cadmium(II) and zinc(II) sulfides, which are capable of subliming at the combustion temperatures of their precursors, these parameters can be varied in wide ranges.  相似文献   

2.
采用4,4'-二氯苯砜、4,4'-二氟二苯甲酮等为原料,通过两步法制备得到不同酮基含量的聚芳硫醚砜/酮聚合物(K-PASS).采用红外光谱、X射线光电子能谱、搭接剪切性能等测试对聚合物的制备以及聚合物与钛合金的搭接剪切强度进行了研究.结果 表明,通过常压法成功制备了不同酮基含量的K-PASS,K-PASS与钛合金的搭接...  相似文献   

3.
TiB2材料具有高熔点、高硬度、耐磨、耐腐蚀、抗氧化以及导电性好和导热性好等优点,是一种具有广泛应用前景的新型陶瓷材料.但是其极强的共价键晶体结构和较低的自扩散系数,使得其很难获得致密的陶瓷材料.主要从添加助烧剂和烧结技术两方面介绍了TiB2陶瓷活化烧结方法的研究进展,并分析了该技术促进材料烧结致密化的机制,同时介绍了热压烧结和放电等离子(SPS)烧结技术.  相似文献   

4.
Copper sulfide films were deposited by spray pyrolysis using aqueous solutions of copper salt–thiourea complexes. The phase composition of the deposits was shown to depend on the nature of the precursor complex, which is governed by the anion of the copper salt and, accordingly, the redox reactions in the starting solution.  相似文献   

5.
聚乳酸类材料作为可生物降解性材料具有广阔的应用前景。设计、合成了6种含半不稳定边臂的希夫碱配体L1—L6,并与钛酸四异丙酯络合合成相应的6种配合物C1—C6,配合物的结构和化学组成经元素分析、红外测试确定。将其作为催化剂催化丙交酯开环聚合,以催化剂C1为考察对象,系统研究了催化剂用量、温度、时间对聚合反应的影响,发现当单体与催化剂配比为2 000,温度为160℃,反应24h时,聚合产率最高,达90.35%,聚合物分子量达8.41×104。在上述优化条件下,比较了催化剂C1—C6的活性,结果表明催化剂活性按以下顺序递减:C6C4C3C1C2C5,同时,催化剂中心金属钛原子周围位阻相对稍小,配体中含配位能力较弱的半不稳定O边臂均有利于提高催化剂的活性。  相似文献   

6.
Chemical interaction between titanium and nitrogen during mechanical activation is studied. The results demonstrate that mechanical activation of titanium powder in a planetary mill leads to a thermal explosion and the formation of titanium nitride nanopowder.  相似文献   

7.
利用水溶液提拉法,把籽晶放在育晶器的底部,沿〈110〉方向进行提拉生长,生长出了截面较大的KDP单晶12mm×12mm×31mm。〈110〉方向的生长速度较传统的溶液降温法得到了一定的提高。这主要是由于提拉使得晶体在提拉方向上的溶质边界层梯度持续发生变化造成的。  相似文献   

8.
张玮  尚青亮  刘捷  马泉泳 《材料导报》2018,32(Z2):379-381
本实验选用氢化钛粉代替传统氢化脱氢(HDH)钛粉为原料,通过成型-烧结(脱氢)工艺制备纯钛。研究烧结温度和烧结时间对纯钛相对密度的影响,确定制备纯钛的最优工艺条件。最终确定氢化钛粉烧制备结纯钛的最优工艺条件为:升温速率为10 ℃/min,烧结温度为1 200 ℃,烧结时间为4 h。实验制备的烧结纯钛符合ASTM B348标准中等级4的规定,烧结件平均抗拉强度σb能够达到601.7 MPa,平均延伸率δ为20%,截面收缩率ψ平均为25.67%。  相似文献   

9.
四氯化钛络合法制备单分散纳米二氧化钛   总被引:13,自引:0,他引:13  
以四氯化钛为原料,通过和三乙醇胺反应形成可溶性络合物,在145℃陈化反应,制得单分散性较好的二氧化钛颗粒.用TEM和XRD测定了颗粒的晶型和形貌.颗粒的大小可通过改变陈化液的pH值进行调节.讨论了钛可溶性络合物的形成和水解过程,测定了该络合物的紫外吸收特性.  相似文献   

10.
分别以硝酸镍和硫脲作镍源及硫源、以乙二醇作溶剂,采用溶剂热技术成功地制备了Ni3S2,α-NiS和NiS2粉体。研究结果显示原料的配比及反应温度能够影响产物的物相组成及形貌。  相似文献   

11.
超重力法制备纳米硫化锌   总被引:10,自引:0,他引:10  
以硝酸锌和硫化氢为原料,在超重力旋转床(RPB,Rotating Packed Bed)中首次制备了球形、粒径分布较窄、分散性较好的闪锌矿纳米硫化锌粒子,平均粒径为30nm,转化率97.5%;研究了陈化时间对粒子形貌和大小的影响.并采用TEM、紫外可见光分光光度计、XRD等手段对产品的形貌、紫外吸收性能及晶相进行了表征.  相似文献   

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14.
Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying (APS). The microstructure and phase composition of the coating were characterized with SEM and XRD, respectively. In addition, the size distribution of the reconstituted powders and the porosity of the coating have been measured. It was found that the reconstitiuted powers with sizes in the range of 20 to 80 μm had excellent flowability and were suitable for plasma spraying process. The assprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains (30~80nm) and large grains (100~200nm). The coating was mainly composed of FeS and SiC, a small quantity of Fe1-x S and oxide were also found. The porosity of the coating was approximately 19 %.  相似文献   

15.
Sulfide removal in petroleum refinery wastewater by chemical precipitation   总被引:2,自引:0,他引:2  
Sulfide removal by chemical precipitation from petroleum refinery wastewater was investigated. The wastewater samples were taken from the flocculation pond influent of TUPRAS Kirikkale Middle Anatolia Petroleum Refinery Wastewater Treatment Plant (WWTP) and physicochemical treatments using conventional coagulants which were partial precipitant [FeCl(3) . 6H(2)O and FeSO(4) . 7H(2)O] and coagulant-aids [Ca(OH)(2) and CaCO(3)] were applied to both raw and sulfide added wastewater. Sulfide and chemical oxygen demand (COD) removal efficiencies of Fe(3+) ions alone for sulfide added wastewaters having different pH values varied between 62-95 and 45-75%, respectively. In addition, removal efficiencies of sulfide (96-99%) and COD (50-80%) were obtained by using Fe(2+) ions together with Ca(OH)(2) as precipitant-aid under the same conditions. In experiments performed with raw wastewater which had different pH values, COD removal efficiencies of Fe(3+) and Fe(2+) ions together with Ca(OH)(2), were 50-80 and 32-50%, respectively.  相似文献   

16.
17.
Recovery of Titanium from the Rich Titanium Slag by H2SO4 Method   总被引:5,自引:0,他引:5  
The blast furnace slag bearing TiO2 in Panzhihua, China, is an important resource to be utilized. In the present paper, the effects of the ratio of slag to H2SO4, the reaction temperature, the particle size of the slag, and the concentration of H2SO4 on the reaction rate and the acidolysis ratio of Ti were studied. The results indicated that the maximum acidolysis ratio reached 98%, which can serve as an experimental basis for the production of titania from the slag.  相似文献   

18.
将聚芳硫醚砜(PASS)和聚苯硫醚(PPS)按照不同的比例通过熔融共混制备高性能合金材料。采用旋转流变仪分析了纯PASS树脂和共混物熔体的流变行为。结果表明,纯PASS树脂通过提高剪切速率和升高温度来改善熔体的流动性效果不佳;在实验范围内,随着合金中PPS含量的增加,合金的加工流动性得到明显改善,当PPS的质量分数为50%时,PASS/PPS合金的熔融加工温度最低,凝胶点降至270℃。  相似文献   

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20.
介绍了电解法制备海绵钛的研究发展,对比传统电解法和新电解法的基本原理、工艺特点及发展状态,指出二氧化钛熔盐电解提取钛的工艺是一种很有前途的提取技术.  相似文献   

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