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1.
主要对添加了不同量稀土Co的Cu-3.0Ni-0.64Si合金进行加工工艺和性能研究.最佳加工工艺为:Cu-3.0Ni-0.64Si合金热轧时,铸锭热轧开坯温度为930℃,保温时间60min;固溶处理温度为900℃,保温时间60min;然后经过约80%的冷变形再进行时效处理,时效处理温度480℃,保温时间210min.研究结果表明:添加0.06wt%Ce的Cu-3.0Ni-0.64Si合金具有最佳综合性能;电导率最高达到48.9%IACS,抗拉强度达到733.17MPa.  相似文献   

2.
烧碱-AQ法麦草浆全无氯漂白的研究   总被引:1,自引:0,他引:1  
研究了烧碱-AQ法麦草浆全无氯漂白(OQP)流程中氧脱木素、整合处理和过氧化氢漂白的影响因素.结果表明;氧脱木素段NaOH用量2.5%,MgSO4用量0.5%,浆浓10%,温度105℃,氧压0.7MPa,时间75min时脱木素效果较好,对后续漂白有利.整合处理pH值为3时,浆料的自度最高,卡伯值最低.压力H2O2漂白的最佳工艺条件为;浆浓10%,H2O2 3.5%,NaOH1.5%,MgSO2 0.05%,EDTA 0.2%,氧压0.6MPa,温度105℃,时间2h.在优化条件下,漂终白度达82.2% ISO.  相似文献   

3.
采用分次分步加料一锅煮合成法,以间甲酚和酸化的木质素磺酸钠来改性制取新的酚醛树脂胶粘剂.研究了酸化反应的时间,合成温度及投料比对胶粘剂性能的影响.结果表明:酸化反应2.5h,合成温度100℃,n(甲醛):n(苯酚+木质素)=0.75:1,n(问甲酚):n(苯酚+木质素)=0.10:1,n(木质素):n(苯酚+木质素)=0.30:1时含游离醛质量分数为0.10%,游离酚质量分数为0.25%,黏度0.38Pa·S,粘合强度2.0MPa,最后用红外光谱和紫外光谱对胶粘剂进行结构测试.  相似文献   

4.
磷钼杂多酸盐催化作用下的SBS环氧化反应   总被引:2,自引:0,他引:2  
用磷铝杂多酸盐为反应控制相转移催化剂,以30%H2O2为氧源,对SBS进行环氧化反应.实验表明:其适宜条件为反应时间2h,反应温度70℃,SBS溶液浓度为100g/L.n(磷钼酸盐):n(过氧化氢)=1.72,过氧化氢(相对于SBS)质量百分用量为27.2%,所得产物的环氧化程度最高为7.63%,催化剂可回收再利用.  相似文献   

5.
木薯渣预处理工艺和酶水解工艺研究   总被引:2,自引:0,他引:2  
以木薯渣为纤维素材料,利用稀酸预处理和绿色木霉产的纤维素酶对植物中的纤维素进行降解,同时,分析了木薯渣的主要组分。结果表明:木薯渣中纤维素含量为46.7%,木质素为16.9%,半纤维素为32.6%;当固液比为1:40,HCI浓度为3.5%,反应时间为3.5h时,进行预处理,可以收到较好的处理效果。当水解温度为55℃,pH=4.8,纤维素酶用量为120FPA/g,水解时间为28h时,还原糖的释放量为0.191mg/mL。  相似文献   

6.
实验研究了低品位钼精矿在氧化焙烧过程中温度、时间、通氧气次数、不同熔剂对钼的氧化转化率的影响.当氧化焙烧过程温度为625℃、焙烧2h、间隙通氧气2次、物料比(物质的量比)为:n(Na2CO3):n(NaNO3):n(Mo)=2:0.5:1时,钼的得率大于98%.  相似文献   

7.
超临界萃取法提取海带多不饱和脂肪酸的研究   总被引:2,自引:0,他引:2  
对以海带(Laminaria japonica)为原料,采用超临界CO2萃取技术提取海藻多不饱和脂肪酸的可行性进行了研究,结果表明,当CO2流量2.5-3.5L/h,萃取压力25MPa,萃取温度30℃,萃取时间3h,原料粒度40-60目,分离压力5MPa和分离温度35℃时最利于海带脂质的提取,此萃取条件可使海带总脂肪酸中多不饱和脂肪酸含量达到67.2%。  相似文献   

8.
催化湿式氧化法处理含酚废水   总被引:13,自引:1,他引:13  
进行了CuO/A12O3、CuO-MnO2/Al2O3、CuO-K2O/Al2O3、CuO/CeO2催化剂在160℃和1.6MPa的氧气压力条件下,催化氧化法处理含酚废水的实验,结果表明催化剂CuO/CeO2具有最高的催化活性,COD为3000ms/L左右含酚废水,反应50min后降解97%。并测定了在135~165℃和1.6MPa氧气压力下。加入催化剂CuO/Al2O3氧化含酚废水的COD与时间的的关系,求取了反应的动力学方程。初步探讨了氧分压和溶液的pH对催化氧化反应速率的影响。  相似文献   

9.
碳酸锰矿浸出工艺条件的研究   总被引:7,自引:1,他引:6  
对菱锰矿的硫酸浸出工艺条件进行了研究,得出了最优浸出工艺条件。当浸出条件为矿酸比1:0.65、温度80℃、时间3.5h和搅拌强度90r/min,菱锰矿中Mn的实际浸出率达到92%左右。  相似文献   

10.
一种催化氧气氧化乙二醛制备乙醛酸的新方法   总被引:4,自引:0,他引:4  
提出了氧化氮(NOn,n=1,2) 催化氧气氧化乙二醛制乙醛酸的方法,讨论了反应机理.当催化剂用量在0.13~0.15 mol(每1 mol乙二醛),原料乙二醛的质量分数为25%,酸性介质使用Lewis酸0.11~0.13 mol(每1 mol乙二醛),反应温度40~50 ℃,氧气压力为0.5 MPa时,乙二醛转化率达到98.7%,氧化选择性79%,产率78%.这种方法与硝酸氧化法相比,较为安全、经济且具有环境污染小的特点,有工业化应用的前景.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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