70t底吹氩钢包水模型实验

针对某钢厂70 t底吹氩钢包进行水模型实验,通过测定不同吹气量下的混匀时间来优化其最佳喷吹位置及示踪剂最佳加入位置;卷渣模拟实验来确定临界卷渣喷吹量。实验研究表明,最佳喷吹位置为原孔及与原孔成180°方向上0.6R处双吹,该喷吹方式下示踪剂最佳加入位置为钢包中心;单吹临界卷渣吹气量为270 L/m in,双吹临界卷渣吹气量为320 L/m in。     

孔板在氢气测量中的应用

在氯化氢工段中,采用S型弯管流量计测量氢气流量,但由于氢气质量低,故在流量小于800Nm3/h时无法监测到测量值,致使氯化氢工段正常生产受到严重安全影响。     

中国大规模空分研究进展（英文）

中国钢铁、化工等行业对工业气体需求的快速增长,极大地促进了大规模空分技术的发展。目前,中国生产的单套空分设备最大氧产量达到了1203 000 Nm3/h,单位能耗为0.38 kWh/m。本文介绍了中国大规模空分技术发展水平,回顾了中国大规模空分工业的发展历史。以成熟的60 000 Nm3/h空分系统为例,详细介绍了分子筛吸附器、空压机、板翅换热器、透平膨胀机和精馏塔等主要设备的技术参数。然后介绍了中国正在发展中的80 000~120 000 Nm3/h空分工艺和装备。最后讨论了中国大规模空分技术存在的主要问题及未来发展方向。     

顶吹转炉渣-金分布性质的水模型研究

通过二维水模型模拟实验,研究了在顶吹转炉吹炼过程中,在不同渣量、不同顶吹气流量、不同枪位条件下,炉渣在钢水中的分布性质.应用分形理论对炉渣在钢液中的分布分形维数进行了计算,讨论了渣量、气体流量及枪位对分形维数的影响,得到了三者对分布分形维数影响的经验公式.     

超声波强化臭氧技术处理造纸废水研究

本文采用超声波强化臭氧技术处理造纸废水,考察了臭氧进气流量、pH值、超声功率和反应时间等因素对COD去除率的影响。实验表明,COD的去除率随着超声功率的增大而增大,而最佳的臭氧进气流量为0.2 m3/h,最佳的pH为8。当进水COD浓度为733.4 mg/L、pH值为8、臭氧进气量0.2 m3/h、US功率100 W,反应时间30 min时,超声波强化臭氧技术的COD去除率为87.3%,而臭氧氧化技术的COD去除率为36.3%,前者比后者高51%,具有明显的优越性。     

苹果渣总酚提取工艺优化

以苹果渣为原料,利用响应面优化法,探究苹果渣多酚的最佳提取工艺.结果表明,苹果渣多酚的最佳提取工艺条件为:提取温度为65℃,提取时间为3.5 h,乙醇体积分数为54.46%,料液比为4∶62.3 g/m L.在此条件下,多酚的实际产量为4.48 GAE mg/g的RSD为1.06%(n=4).     

大孔树脂纯化蓝莓果渣花青素的研究

目的:筛选分离纯化蓝莓果渣花青素的最佳树脂,优化纯化蓝莓果渣花青素的工艺条件。方法:比较AB-8、D101两种大孔树脂对蓝莓果渣花青素的吸附解吸效果,研究了AB-8大孔树脂对蓝莓果渣花青素的吸附解吸条件。结果:AB-8大孔树脂是纯化蓝莓果渣花青素较好树脂,其对蓝莓果渣花青素吸附解吸平衡时间均为4 h;吸附最适温度60℃、样液稀释4倍、p H 3.0、吸附流速1 m L/min时吸附能力最佳,乙醇浓度60%、p H 3.0、解吸流速1 m L/min时解吸能力最佳。结论:该工艺得到的花青素产品为紫黑色粉末,色价为16.90,是未纯化样品色价的5倍。     

超滤膜分离牛血清蛋白的操作条件优化研究

本文采取超滤膜技术进行分离实验,用紫外分光光度计进行分离结果测量.通过聚砜聚乙烯超滤膜分离牛血清蛋白的研究,以主要影响的因素:牛血清蛋白的浓度、流量,膜前后压力来确定影响分离效果的因素,通过配制一系列不同的牛血清蛋白水溶液浓度和吸光度做出的标准曲线,清浓液浓度对比,以及用正交实验的方法对实验数据进行处理,即可得到膜分离的最佳条件.最后由正交实验得出最佳条件为第六组实验条件:浓液流量为8L/h,清夜流量为2.5L/h,膜前压力为0.200Mpa,膜后有压力为0.176Mpa.由最佳条件可知,若要提高超滤膜分离效率,需减小清液流量并且增大膜前压力.     

超临界CO2萃取白簕叶总黄酮工艺的研究

采用超临界CO2萃取白簕叶中的总黄酮化合物,通过单因素试验和正交试验,研究了超临界萃取条件（压力、温度、时间、CO2流量）对其总黄酮的影响.实验结果表明,最佳提取条件：萃取压力20 MPa,萃取温度35℃,萃取时间1 h,CO2流量20 L/h.白簕叶总黄酮提取值为2.929 mg/g.     

CO2与石灰水反应实验的改进

在做CO2与石灰水反应的实验时,新旧教材常用的方法,即向试管中吹气使石灰水变浑浊.该装置不足之处在于:若气流大,则石灰水会外溅,甚至会喷洒在整个脸部.     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

Western and Eastern culture differences in commercial field

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.     

只要努力,不要后悔

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.     

浅谈移民问题

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.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

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.