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1.
优良吸附制冷工质对的研究   总被引:2,自引:0,他引:2  
对水、乙醇和 13x分子筛、硅胶、活性炭以及自制吸附剂NA、NB组成的吸附工质对的制冷性能进行了研究 .用高真空重量法测取了自制吸附剂NA和NB的吸附等温线 ;用热分析法对吸附剂的脱附性能进行了分析 ;在吸附制冷循环实验装置上研究了吸附工质对的制冷性能参数 .结果表明 :①自制吸附剂NA对水的最大吸附量高达 0 .7kg/kg ;自制吸附剂NB对乙醇的最大吸附量达0 .6 8kg/kg ,是活性炭对乙醇吸附量的 3倍 ;②NA 水工质对的制冷量是 92 2kJ/kg ,NB 乙醇工质对的制冷量是活性炭甲醇的 2 .4倍 ;③NA 水和NB 乙醇是环境友好型、无公害的吸附工质对 ,可替代活性炭甲醇工质对用于以低温热源驱动的吸附制冷系统 .  相似文献   

2.
介绍了一种应用于制冷空调领域的新型溶液除湿冷水机组,该系统可以由60~80℃的低品位热能驱动,如太阳能平板集热、余热废热等.对该系统建立了数学模型,理论分析了蒸发温度、再生温度、环境空气温湿度、封闭制冷循环和再生循环空气流量等参数对系统性能的影响.结果表明:系统在参考工况下制冷量为2.5kW,性能系数达0.37,制冷性能良好;再生温度和环境空气含湿量对系统制冷量和性能系数的影响较大,而环境空气温度的影响较小;同时,为了使得系统能够经济运行,再生空气流量不宜过大,而封闭制冷循环空气的流量也需要合理选择.  相似文献   

3.
目前烟气脱硫技术的反应原理多数为化学反应 .本文采用一种新型脱硫剂 ,即用超细TiO2 粉末经过低温烧结和表面活化制得的高孔隙率 ,高比表面积的TiO2 颗粒 ,进行烟气脱硫的试验研究 ,其脱硫机理主要是物理吸附 .在不同吸附温度下 ,对 4种TiO2 颗粒吸附剂在固定床中进行了动态脱硫试验 .试验结果表明 ,该吸附剂的脱硫能力主要与以下 3个因素有关 :TiO2 粒子的品质 ,吸附温度以及烟气中SO2 的浓度 .TiO2 具有较好的吸附性能和工业应用前景 .烧结温度在 4 4 0~ 5 4 0℃之间时 ,吸附剂的晶态形成有利于其吸附性能的提高 ,试验最佳吸附温度为 12 0℃ .  相似文献   

4.
本介绍了一种新型水处理剂——氢氧化铝镁正电纳米粉末(AMH)。研究了AMH对水溶液中Cr(Ⅵ)的吸附性能,考察了吸附时间、pH、SO^2-4、Cr(Ⅵ)浓度对吸附的影响。结果表明,吸附可以在4min之内达到平衡;在DH5—7时吸附效果最好:随着Cr(Ⅵ)浓度的增大吸附量逐渐增大,最大吸附量达110mgCr/g;吸附不受SO^2-4的影响。吸附等温线符合Freundlich模式,吸附机理主要为离子交换吸附,Cr(Ⅵ)主要以Cr2O^2-7的形式被吸附。吸附剂用0.2mol/L FeCl2的酸性溶液进行再生,再生效率达100%。  相似文献   

5.
膨润土经酸活化后,对废机油吸附再生效果良好.其最佳再生工艺参数为:吸附剂用量20%,吸附温度55-60℃,搅拌时间20-30 min.  相似文献   

6.
以牡蛎壳为原料,通过煅烧方法制备牡蛎壳吸附剂.考查了溶液pH值、牡蛎壳煅烧温度、煅烧时间、粒径、吸附剂用量、初始浓度和吸附时间等因素对直接大红4BS和孔雀石绿吸附性能的影响.结果表明,直接大红4BS和孔雀石绿的最佳pH分别为1.0和8.0.在200℃煅烧5h后,采用100目0.8g吸附剂吸附染料,去除率达最大值.运用三种动力学模型对吸附过程进行拟合,结果表明吸附过程可以很好地用准二级动力学方程描述.吸附等温线用Langmuir方程的拟合效果优于Freundlich方程,吸附剂再生后,可循环使用5次以上.  相似文献   

7.
以凹凸棒为载体,采用浸渍-焙烧的方法制备了负载氯化镁凹凸棒吸附剂,并对含铅废水进行处理.以铅的去除率为评价指标,通过正交及单因素实验确定了吸附剂的最佳制备工艺和最适吸附条件.氯化镁加入量为凹凸棒的5%,浸渍时间为2h,焙烧温度为500℃,焙烧时间为3h;铅的初始浓度为40mg/L,吸附剂投入量为20g/L,25℃,吸附14h,铅的去除率为97.06%.该吸附过程服从Langmuir吸附模型,饱和吸附量为10.5296mg/g.  相似文献   

8.
以凹凸棒为载体,采用浸渍-焙烧的方法制备了负载氯化镁凹凸棒吸附剂,并对含铅废水进行处理.以铅的去除率为评价指标,通过正交及单因素实验确定了吸附剂的最佳制备工艺和最适吸附条件.氯化镁加入量为凹凸棒的5%,浸渍时间为2h,焙烧温度为500℃,焙烧时间为3h;铅的初始浓度为40mg/L,吸附剂投入量为20g/L,25℃,吸附14h,铅的去除率为97.06%.该吸附过程服从Langmuir吸附模型,饱和吸附量为10.5296mg/g.  相似文献   

9.
柠檬酸改性竹屑吸附亚甲基蓝的动力学和热力学分析   总被引:1,自引:0,他引:1  
为拓宽竹材剩余物的开发应用新途径。以竹屑为原料,柠檬酸为改性剂,制备了柠檬酸改性竹屑吸附剂,以亚甲基蓝(MB)为吸附对象,考察了pH、时间、吸附剂投量及吸附温度等对吸附剂吸附MB效果的影响,并对其吸附动力学和热力学进行了分析。结果表明:溶液pH增大,吸附剂对MB的吸附量增大,pH在5-9间变动,吸附剂对MB吸附量变化不大;染料初始浓度和吸附温度增加,吸附剂对MB吸附能力增强;在吸附120min,吸附达到平衡,吸附动力学过程符合二级动力学模型,吸附热力学过程符合Langmuir模型;在25℃、35℃、45℃时,吸附剂对MB的最大吸附量分别为106.38 mg/g、121.95 mg/g和125mg/g;竹屑吸附剂对MB的吸附过程是一个吸热的自发过程。  相似文献   

10.
第Ⅰ卷 (选择题 共 3 6分 )一、选择题 (单项选择 ,共 3′× 12 =36分 )1 下列运算正确的是(A)x3 +x3 =2x6  (B)x6÷x2 =x3(C) ( - 3x3 ) 2 =3x6  (D)x2 ·x-3 =x-12 某粮店出售的三种品牌的面粉袋上 ,分别标有质量为 ( 2 5± 0 .1)kg、( 2 5± 0 .2 )kg、( 2 5± 0 .3)kg的字样 ,从中任意拿出两袋 ,它们的质量最多相差(A) 0 .8kg  (B) 0 .6kg  (C) 0 .5kg  (D) 0 .4kg3.小亮从一列火车的第m节车厢数起 ,一直数到第n节车厢 (n >m ) ,他数过的车厢节数是(A)m +n   (B)n -m(C)n -m - 1   (D)n -m +1第 4题图4 如图 ,四边形A…  相似文献   

11.
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.  相似文献   

12.
风的曲线     
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.  相似文献   

13.
Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.  相似文献   

14.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

15.
Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language.  相似文献   

16.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

17.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

18.
19.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

20.
This paper looks at the way drama works to bring a model of an arts curriculum into reality. He also shows how drama is valuable when discussed as a separate, autonomous subject in the school curriculum as opposed to one subsumed within English. He argues for a view of the arts and gives an example of a sequence of work in an English GCSE class based around Arthur Miller's play View from the Bridge. From this he draws out several strands about the relationship of the drama curriculum to the individual students and teachers, the school, and to culture. He also emphasises the primacy of performance in drama education.  相似文献   

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