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1.
笔者介绍了1025t/h燃煤锅炉加入燃烧添加剂后,锅炉水冷壁的沾污减轻,锅炉减温水量减少,排烟温度降低,同时空预器的吹灰效果改善,锅炉热效率有所提高。  相似文献   

2.
周鸿  山杉公男 《江西科学》2003,21(2):95-100
探讨DHA降胆固醇的机理并对其剂量依赖性及时效性进行研究。将Wister大鼠分别给予含DHA(0.2%,0.4%,0.6%,1.0%,1.5%,2.0%)饲料喂养,检测其血脂的含量。其结果是胆固醇降低与DHA添加剂量成正比;血和肝微粒体中的亚油改比与饲料中DHA添加量成正比;16:0—18:2磷脂酰胆碱(PC)也随之增加。  相似文献   

3.
含氮硼酸酯润滑油添加剂的合成与性能测试   总被引:4,自引:0,他引:4  
用硼酸与十六醇和乙醇胺反应合成了含氮硼酸酯润滑油添加剂.合成的最佳工艺条件为十六醇、硼酸和乙醇胺摩尔比为1.2:1:2.6,脱水反应6h.用四球机测试了含该添加剂0.1%~7%的基础油的抗磨性能.四球机试验结果表明含氮硼酸酯添加到基础油中,能显著提高其抗磨性能,且添加量存在一个最佳值.  相似文献   

4.
本文从工业锅炉排放烟气量影响锅炉热损失的观点出发,分析研究有关降低过剩空气量燃烧,以减少排烟热损失,从而降低燃烧消耗量,以及提高锅炉热效率一类问题。采用低过剩空气系数燃烧控制系统,以及有氧量修正的控制方案,是当前提倡经济燃烧,实现节能的方向。  相似文献   

5.
868菌发酵物用作大黄鱼和鲈鱼饵料添加剂的初步试验   总被引:4,自引:0,他引:4  
以饵料0.5%的量添回868菌发酵物,作为大黄鱼(厦门),大黄鱼(连江)和钙鱼饵料添加剂,它们的日增长率分别比对照提高16.1%,18.8%和32.5%,日增重率分别比对照提高12.5%,21.4%和16.4%,同时,大黄鱼(厦门),大黄鱼(连江)和鲈鱼钌料系数比对照分别降低17.7%,9.4%和20.1%,结果表明:868菌发酵物作为饵料添加中以促进大黄鱼和鲈鱼的生长,并且可以提高它们的饵料效率。  相似文献   

6.
为降低锅炉NO的排放,研究焦炭在固定床中燃烧时的氮氧化物排放特性,分析焦炭数量对NO排放的影响。在其他条件不变的情况下,取焦炭质量分别为0.5、1.0和2.0g的煤样进行燃烧实验。结果表明:焦炭燃烧NOx排放与燃烧过程密切相关,在固定床中有还原层存在时,NO排放处于低水平稳定状态。随着焦炭还原层的消失,NO转化率迅速增加。在设计层燃燃烧锅炉时。加大燃煤炉中焦炭层的厚度.可以降低锅炉NO的排放.焦炭层厚度增加4倍.NOx排放降低73.86%.  相似文献   

7.
用吸附还原与三元催化器组合降低富氧汽油机NOx的排放   总被引:1,自引:1,他引:1  
采用稀燃技术虽可大幅改善汽油机的燃油经济性和排放性,却因稀燃的富氧燃烧使NOx降低较少.为此,采用吸附还原催化转化器与三元催化转化器的不同组合方案,对一台电控燃油喷射16气门稀燃汽油机进行了降低富氧条件下NOx排放的试验研究.试验结果表明:三元催化转化器位于吸附还原催化转化器之前的布置方案具有最好的降低稀燃汽油机NOx排放的效果.在该试验条件下,NOx催化转化率最高可达到97.3%。  相似文献   

8.
乳酸钙和抗坏血酸强化豆乳的工艺条件的研究性试验结果表明:钙盐浓度和PH值大小明显影响制品的品质、乳酸钙强化的适宜浓度为0%-0.09%,PH值为5.5-7.5;抗坏血酸强化适宜添加量为10mg%,PH值为6.30-7.50;最适的加糖量为8%,稳定剂以海藻酸钠为佳,适宜添加量为0.1%。成品通过感官评尝,具有明显的奶香味,甜酸可口。  相似文献   

9.
Mn掺杂对BaTiO3体系介电性能的影响   总被引:1,自引:0,他引:1  
采用氧化物混合方法制备以BaTiO3为基础的X7R陶瓷材料。研究了添加剂Mn的添加量对体系介电性能的影响,并对微观结构进行分析。Mn的加入起到了助熔剂的作用,提高陶瓷的介电常数。Mn离子在2+和3+之间变价,可以减少缺陷的数量,因而减小tanδ,满足EIAX7R标准的要求。实验表明,添加0.046wt%MnCO3的BaTiO3体系,具有最优的介电性能。其主要工艺条件和性能参数为:烧结温度1240℃保温6h,在1kHz下ε≈5800,tanδ≤1.5%,介电常数温度变化率-15%〈△ε/ε〈15%,绝缘电阻率:ρv≥1×10^12Ω.cm。  相似文献   

10.
新型燃油添加剂对汽油机燃烧与排放的影响   总被引:3,自引:0,他引:3  
为了探讨新型多效燃油添加剂(代号MAZ)对车用汽油机燃烧和排放特性的影响,文中介绍了燃油添加剂的功用和基本工作原理,并在汽油机试验台架上,进行了一系列燃油中添加剂在等同工况下的外特性试验和负荷特性试验.试验结果表明,燃油添加剂MAZ能有效改善汽油机的燃烧过程,排气中CO,HC的排放分别减少11.6%~19.6%和22.9%~25.2%.  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

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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