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1.
小型可调式变压吸附制氧装置性能的实验研究   总被引:1,自引:0,他引:1  
利用自行研制出的小型可调式变压吸附制氧装置研究了冲洗量、出口流量和出口压力对产品气氧浓度的影响。实验结果表明,1.当出口流量越大时,出口压力越小,反之亦然。2.压力对氧浓度影响很大,压力增高,氧浓度迅速增大。3.出口富氧浓度与流量大小有密切关系,还与冲洗量大小有关。出口流量的增大会引起产品气氧浓度的降低。当冲洗量过大或过小时,减小流量,氧浓度提高不大。对于冲洗量适中的情况,流量小于2L/min时,减小流量,浓度提高很快;但当流量大于2L/min时,降低流量,浓度变化不大。4.冲洗量对浓度影响较大,当冲洗量适中时(阀门角度为180°),产品气氧浓度较高,过大或过小时都会降低富氧浓度。本装置产品富氧气中氧气浓度最高可达到75%,其流量为05L/min,当富氧浓度为55%时,流量可达35L/min,说明本装置完全达到并超过了设计要求,很适合于氧巴和家庭。  相似文献   

2.
秦蔚  吴磊 《制冷学报》1996,(4):7-11
本文进行了非共沸混合制冷剂HFC-32/HFC-134a水平管内的强制对流沸腾换热实验。HFC-32的质量分率为0.10,0.25和0.40,热流密度为6,12,24,36,48和60kw/m^2,质量流量为10,15,22,30和46g/s,实验段进口压力保持为0.4Ma。实验结果表明混合制冷剂的强制对流蒸发换热存在退化现象。  相似文献   

3.
研究了不同电镀规范的Fe-Ni-P合金层显微硬度和摩擦学性能。镀液中Fe/(Fe+Ni)浓度比增大或电流密度增加,镀层的硬度上,耐磨提高;槽液的PH值或温度增大,镀层的显微硬度下降,耐磨性降低。镀液NaH2PO2.H2O浓度为5g/L时,镀层硬度和磨性最高。宜选用的工艺参数为PH值1.0-1.2,温度60-70℃,电流密度10-20A/dm^2。Fe-Ni-P非晶合金的耐磨性比Ni-P非昌合金高2  相似文献   

4.
用微波等离子体化学气相沉积(MP-CVD)方法生长氮掺杂金刚石薄膜,研究发薄膜场电子发射性能。实验结果表明,不同氮源气体流量下制备的榈均呈现连续而稳定的场电子发射,但发射性能对氮源气体流量有强烈的依赖性。随着氮源气体流量由0逐渐增大到0.5cm^3(STP)/min,发射的开启电压从1050V逐渐减小为150V,而当氮流量超过0.5cm^3(STP)/min时,开启电压则不断增大,当氮流量为3.0  相似文献   

5.
研究了不同电镀规范的Fe-Ni-P合金层显微硬度和摩擦学性能。镀液中Fe/(Fe+Ni)浓度比增大或电流密度增加,镀层的硬度上升,耐磨性提高;粮液的pH值或温度增大,镀层的显微硬度下降,耐磨性降低。镀液NaH2PO2·H2O浓度为5g/L时,镀层硬度和耐磨性最高。宜选用的工艺参数为pPH值1.0~1.2,温度60~70℃,电流密度10~20A/dm2。Fe-Ni-P非晶合金的耐磨性比Ni-P非晶合金高2倍,摩擦系数低20%。  相似文献   

6.
刘磊  周芳德 《计量学报》1994,15(2):126-131
在内径为30mm的垂直上升管中,应用互相关分析和U型光导纤维探针,对水一气两相流和油-气两相流进行了各分相流量测量的实验研究,考虑了流型和雷诺数对流量测量的影响,同时研究了含气率的测量,提出了计算平均含气率的关系式。对水-气两相流,试验的气相折算流速范围为0.22~3.00m/s,波相折算流速范围为0.11~3.00m/s;对油一气两相流,试验的气相折算流速范围为0.10~19.01m/s,液相折算流速范围为0.35~1.65m/s。  相似文献   

7.
研究了Ti-Mg催化剂(MG型)的乙烯-1-丁烯气相共聚合。常压下聚合动力学曲线为衰减型。催化效率为10.2-11.0kg PE/gTi,产物密度d=0.905-0.922g/cm^3。Φ-100流化床共聚合(1.2PMa)催化效率为137-173kgPE/gTi。产物特性粘度「η」MI2.16、MFR10.0/2.16分别为1.09-2.22、1.0-6.9、7.8-10.4。共聚物熔点、结晶度  相似文献   

8.
合成了添加过量PbO后的Pb(Zn1/3Nb2/3)O3-PbTiO3(PZN-PT)系陶瓷,并研究了其相结构及介电性能,在(1-x)PZN-xPT(0.1<x<0.2)系陶恣体中,添加过量PbO提高了钙钛矿结构的稳定性,但过多地添加PbO不利于提高其介电性能。当PT的摩尔浓度为14-19mol%时,这些组分最大介电常数和温度的关系与频率无关,而其介电常数的温度特性及仍随频率变化而弥散。  相似文献   

9.
无Co混合导电型陶瓷透氧膜的制备和性质研究   总被引:2,自引:0,他引:2  
李思温  丛铀 《膜科学与技术》1997,17(6):16-19,33
首次合成了Sr10-n/2BinFe20Om(n=2,4,6,8,10等)系列氧化物透氧膜,它们具有较高的透氧能力,其中,样品n=10在1100K时的透氧率为0.90ml(STD)/(cm2·min),比Sr1-xBixFeO3高约两倍.Sr1-xBixFeO3(x=0.1,0.3,0.5)系列的透氧率随Bi含量增加而增大.通过两个系列氧化物的XRD和化学组成的对比,发现Bi离子含量和晶格空位浓度对透氧能力大小起决定性作用.  相似文献   

10.
以高岭石和NaTi2(PO4)3为基的钠快离子导体   总被引:3,自引:1,他引:2  
本文以高岭石为起始原料、以NaTi2(PO4)3为母体结构,通过高温固相反应合成快离子导体Na1+2xAlxTi2-xSixP3-xO12系统,并研究了此系统的相组成、结构和电性能.大多数合成反应在1073~1223K下完成.在。x<0.6的组成范围内可形成具有NASICON结构、空间群为C2/c的固溶体·x射线粉末衍射分析表明随。的增大,系统各合成物的晶胞参数增大.x=0.4的合成物具有最好的离子电导率,673K时达3.00×10-3S/cm,而激活能为36.02kJ/mol.  相似文献   

11.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

12.
Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.  相似文献   

13.
In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.  相似文献   

14.
Quality Study of Honeycomb Core Shaping Without Wax Stabilization   总被引:1,自引:0,他引:1  
Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.  相似文献   

15.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

16.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

17.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

18.
Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.  相似文献   

19.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

20.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

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