共查询到20条相似文献,搜索用时 65 毫秒
1.
Dinesh Singh J. K. Gehlawat Musti S. Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,47(2):127-136
Oslefins and diolefins are important intermediates in the petrochemical industry and the future promises a further substantial increase in demand. While several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene, these catalysts are inefficient in the abstraction of first hydrogen from butane. Bismuth molybdates (β and γ-phases) containing iron oxide and supported on alumina are used as catalysts in the present investigation on the oxidative dehydrogenation of n-butane. Effects of catalyst content, temperature and oxygen: n-butane ratio on conversion and selectivity to butadiene and (C4H8 + C4H6) are studied in the following ranges of experimental conditions: β-bismuth molybdate/100 mol support I(K), 3–9; γ-bismuth molybdate/100 mol support I(K), 5-20; temperature, 400–500°C; O2: butane ratio, 0.6:1.7. 相似文献
2.
3.
4.
通过单因素实验研究了工艺操作参数如粉尘含量、平均过滤速度和单位过滤面积的加料量(简称面加料量)对粉尘在布袋上沉积规律的影响.研究结果表明,粉尘在布袋长度方向上分布不均,中间凸起,上下两端逐渐减薄;在平均过滤速度和面加料量一定时,粉尘含量对粉尘层分布的影响可以忽略不计;平均过滤速度和面加料量对粉尘层的影响显著.还采用Gu... 相似文献
5.
《Journal of Adhesion Science and Technology》2013,27(2):247-257
To study the photo-grafting performance of acrylamide (AM) onto cellulose and the mechanical behavior of grafted cellulose, Whatman 41 filter paper was grafted with 30% AM in methanol by UV radiation using in situ technique. The amount of grafting (Gf) and tensile properties like tensile strength (TS) and elongation at break (Eb) were studied. In order to improve the tensile properties, cellulose was pretreated under UV and gamma radiations at different radiation intensities and subjected to grafting with 30% AM under in situ UV radiation. Cellulose was also pretreated by alkali (5% NaOH) along with UV and gamma radiations with different intensities and grafted with AM under UV radiation. Among the treatments, the alkali + UV irradiated 30% AM grafted sample showed the best mechanical performance (TS = 200%, Eb = 250%). 相似文献
6.
石灰石品质对生料易烧性影响的研究 总被引:2,自引:0,他引:2
将化学分析方法和物理性能测试方法相结合,综合分析石灰石品质。在实验室进行生料易烧性试验,在同样试验条件和不同品质石灰石参与配料的情况下,通过测试灼烧后熟料中的fCaO含量,研究石灰石品质对生料易烧性能的影响,为实际生产提供理论参考。 相似文献
7.
为了改变目前煤油水三元煤浆难以储存和运输的现状,选择对煤浆进行磁化。在磁感应强度为0.1~0.5 T,磁化时间为0~12 min的条件下,研究了磁化对神木煤和大同煤三元煤浆性能的影响。结果表明:在研究的磁场强度范围内,磁化时间为0~10 min时,神木煤煤浆和大同煤煤浆的粘度逐渐降低,流动性得到改善,三元煤浆稳定性得以提高。随着磁化时间的延长,在10~12 min时,煤浆的粘度开始升高。研究还发现,实验开始后的48 h,随着磁场强度的增大,2种三元煤浆的析水率总体呈下降趋势。研究表明,适当的磁化时间和磁场强度可以提高煤浆的稳定性,从而有利于煤浆的储存和输送。 相似文献
8.
G. S. Perry A. S. Weatherburn C. H. Bayley 《Journal of the American Oil Chemists' Society》1957,34(10):493-495
Summary In the case of sorption on cotton there was an approximately linear increase in sorption of the detergent with increasing
builder concentration. The effectiveness of the builders in this respect increased with increasing anionic charge and decreasing
pH of the builder. In the case of sorption on carbon the addition of builder again led to an increase in sorption, but in
this case the sorption was an exponential function of the builder concentration. The differences in effectiveness of the various
builders in increasing sorption was less clear-cut than in the case of sorption on cotton, and there did not appear to be
any consistent correlation between the amount of detergent sorbed and either the pH or the anionic charge of the builder. 相似文献
9.
采用实验方法考察工艺参数对沉降斑的影响。基于一个带凸台的平板模具,采用L27(313)正交矩阵进行实验,研究了几何尺寸、熔体温度、注射时间、保压压力及保压时间对厚度突变处沉降斑形成的影响,同时还考虑了熔体温度和注射时间以及保压压力和注射时间之间的交互作用影响;通过性噪比分析和F检验优化成型工艺条件并对工艺参数的影响进行显著性分析。结果表明,对于厚度突变的平板制品,厚度突变的程度对其沉降斑形成的影响最大,其次为熔体温度,保压压力,保压时间等;采取减小厚度变化,降低熔体温度或增加保压压力和保压时间等措施,可以减小厚度突变处沉降斑,从而减少其对外观质量的影响;因素之间的交互作用对制品沉降斑的形成有一定的影响,熔体温度B和注射时间C之间的交互作用影响较为明显,而保压压力D和注射时间C之间的交互作用对该质量指标的影响最小,可以并入误差。 相似文献
10.
无机盐对表面活性剂去污力影响的研究 总被引:3,自引:1,他引:2
用去污实验机测定了直链烷基苯磺酸钠(LAS)、脂肪醇聚氧乙烯醚硫酸钠、α-烯基磺酸钠、脂肪酸甲酯磺酸钠等阴离子表面活性剂的去污力,考察了无机盐对去污力的影响。结果表明,三聚磷酸钠使这几种表面活性剂的去污值增加了29.11%~121.26%,磷酸三钠使LAS的去污值增加了128.25%;三聚磷酸钠、δ-层状结晶二硅酸钠、4A沸石等软水剂增强去污力的效果最好,碳酸钠和硅酸钠等碱性助剂次之;硫酸钠、氯化钠、磷酸二氢钠和十水四硼酸二钠不适合用作洗涤剂的助洗剂。 相似文献
11.
设备内部气体可能存在湍流流动状态,设备壁面形成沟槽形式可能会对原流动状态产生影响从而影响设备性能。以前相关研究很少,但设备内部气体是否存在湍流流动状态,流动状态改变是否会对设备性能产生影响还需要进一步研究。为研究壁面形成沟槽形式对原湍流流动产生的影响,对流动状态变化前后沿壁面温度分布进行了计算,采用脉动温度符合一定概率分布的方法计算了脉动温度,对流动状态变化时温度场变化情况进行了分析。 相似文献
12.
The effect of γ irradiation on reverse osmosis (RO) semipermeable membranes has been studied in order to evaluate their performance under the radiation environment arising in the processing of various streams in nuclear industry by reverse osmosis process. Both cellulosic and noncellulosic membranes in dry as well as wet conditions were used. A Co60 source was used for γ doses from kilorads to megarads. The transport properties, namely, salt retention and water flux of membranes determined before and after irradiation, suggested deterioration in the membrane properties due to irradiation. The tensile strength and viscosity of membrane polymer also suggested membrane degradation. Differential scanning calorimetry was taken to look into any structural changes in the membrane polymer as a result of irradiation. IR spectra and X-ray of membrane polymer was also undertaken to understand the changes on the molecular level. 相似文献
13.
14.
采用四种表面活性剂体系,包括硅酮系表面活性剂DC-193、非硅酮系表面活性剂吐温-80、DC-193与吐温-80复配体系,以及JFC复配体系,研究了不同表面活性剂体系对酚醛泡沫性能的影响。研究结果表明:采用DC-193与吐温-80复配体系时,泡沫的综合性能最好。采用SEM观察了泡沫的孔结构,还进一步研究了DC-193与吐温-80。复配体系的用量对泡沫表观密度和吸水率的影响,并简单分析了机理。 相似文献
15.
16.
以不同相对分子质量的聚乙二醇(PEG)为引发剂,通过开环聚合引发丙交酯和己内酯单体合成聚己内酯–丙交酯–聚乙二醇(PCLA–PEG)的共聚物;用六亚甲基二异氰酸酯(HDI)对合成的共聚物进行封端,并进行扩链反应制备一系列PEG含量不同的生物可降解聚氨酯。通过红外以及DSC研究了PEG含量对聚氨酯材料结构的影响,发现采用相对分子质量较高的PEG制备的材料,其软硬段相分离程度较高;另外对样品的力学性能、亲水性及降解性进行了测试,发现PEG含量增加,样品的力学性能下降,亲水性能提高,降解速度加快。 相似文献
17.
18.
19.
20.
微相分离对聚氨酯弹性体耐热性能的影响研究 总被引:2,自引:0,他引:2
在聚氨酯弹性体固化过程中添加微相分离促进荆,对不同温度下的热失重分析(TGA)和力学性能高温保持率进行了对比分析,分析表明,添加了微相分离促进剂的聚氨酯弹性体耐热性能得到了提高。 相似文献