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1.
采用MR-GC80型压力微反装置,在空速2h~(-1)、氢油分子比8:1、氢压2MPa、反应温度260℃和280℃反应条件下,考察了钯/氢型丝光沸石(Pd/HM)催化剂的含钯量对正己烷异构化反应活性,选择性,稳定性的影响,并结合脉冲激反装置对反应机理进行了探讨。结果表明:钯含量在0.025—0.25%范围内,活性和选择性均随含钯量的增加而提高;超过0.85%,则呈下降趋势;HM载钯后稳定性有明显的改善。催速失活试验表明:0.25%Pd/HM和0.5% Pd/HM催化剂具有相同的稳定性。在Pd/HM上正己烷异构化反应的机理为酸性和双功能结合的复合机理。  相似文献   

2.
采用共沉淀沉积法制备了一种适用于富碳合成气一步法合成二甲醚(DME)的高活性催化剂C207-HZSM-5。考察了催化剂配比、还原条件、反应温度等对催化剂性能的影响,并采用程度升温还原(TPR)方法及XRD表征,对催化剂的还原性能及催化剂氧化态、还原态、反应后的物相结构进行了分析。结果表明,还原时,低升温速率有利于催化剂活性的提高。在p=3MPa、T=280℃、空速为3000mL/(g·h)条件下,CO转化率为66.03%,DME收率为45.5%,接近其热力学平衡值。结合活性评价结果及不同还原温度下的XRD结果得出,Cu+是催化剂的主要活性物种。TPR结果表明,还原分两步进行,即165℃处的Cu2+还原至Cu+过程,和175℃处的少量的Cu+还原至Cu0过程。  相似文献   

3.
对文题进行了研究。稀土对钒-铁系催化剂的助催化作用与其晶格结构和传递氧的功能有关。关联了CeO_2、Pr_2O_3与Nd_2O_3的稀土效应与其原子序数的关系,发现丙烯选择性随原子序数增加而提高。提出丙烷催化氧化脱氢制丙烯催化剂的组分为V-Fe-Nd-Al-O,讨论了反应温度、原料配比、空速等因素对催化剂性能的影响,当反应温度625℃、空气/丙烷=2.38∶1(mol比)、空速1200h~(-1)时,丙烷的转化率为40.32%,丙烯选择性66.20%,丙烯收率为26.69%。  相似文献   

4.
用Zn盐对ZSM-5分子筛进行改性,考察其在混合C_4烃类芳构化上的催化效应和工艺条件。实验表明,Zn-ZSM-5催化芳构化的性能优于ZSM-5催化剂。在反应温度520~530℃、重量空速1.0h~(-1)以及常压不临氢条件下,连续反应8h,C_4~C_8芳烃的收率逸42%(wt),液态烃中芳烃含量高达99%(wt)。催化剂累计反应160h,每反应8h后用空气再生2h,其催化活性仍可保持不变。  相似文献   

5.
研究了在充有惰性液体介质的机械搅拌三相床反应器中含氮合成气一步法合成二甲醚的工艺条件,催化剂是由甲醇合成催化剂与甲醇脱水催化剂均匀混合组成的双功能催化剂,粒度为0.15~0.18mm。在温度220~260°C、压力3~7MPa、空速800~2000mL/(g·h)条件下考察了温度、压力、空速及搅拌转速对CO转化率及二甲醚选择性的影响,结果表明240~260°C、7MPa及1000mL/(g·h)是合成二甲醚较佳的反应条件。实验还考察了催化剂含量及气体组成对反应的影响,结果表明H2/CO高时CO转化率较高。  相似文献   

6.
以活性炭为载体,钾为助剂,浸渍法制备了Fe/活性炭催化剂,在固定床反应器中考察了不同铁含量、助剂、载体的催化剂的催化性能。结果表明Fe/椰壳活性炭具有较高的一氧化碳转化率和C+5烃收率。考察了反应温度、压力、空速等对费-托合成的影响。在Fe/椰壳活性炭催化剂上,适宜的温度(300~350°C),中压(2.5MPa)及较低空速(1000h-1)有利于合成气合成液体燃料。  相似文献   

7.
研制了蜂窝状氧化铝载体浸涂Cu、Mn过渡金属及稀土(La、Ce)氧化物的催化燃烧催化剂。以乙醛-空气为模拟气,研究了各种反应条件对乙醛净化率的影响。结果表明;在210℃,乙醛浓度1.6—2.0g/m~3,空速13000h~(-1)条件下,该催化剂对乙醛完全氧化有良好的活性;对废气的浓度有较宽的适用范围。经酸性气体(含醋酸2%)反应近100小时,催化活性仍保持不变,且水蒸汽的存在有利于催化剂的使用寿命。工厂测试表明,在进口温度150—200℃,废气即可起燃,出口气体中几乎检测不到乙醛、丙烯醛等含氧化合物,使用近2000小时,催化剂仍保持良好的活性。  相似文献   

8.
以分子筛型固体酸代替氢氟酸作催化剂,研究了长直链烯烃和苯的烷基化反应。对各种类型分子筛的研究表明:以金属阳离子交换的Y型分子筛为催化剂,在常压、苯/烯=8(摩尔比)、烯/剂=6(重量比)的条件下,反应0.5小时,烯烃的转化率可达97%以上,苯的单烷基化的选择性在90%以上。提高反应温度和压力可进一步提高烯烃的转化率,当反应温度150℃、压力2MPa、重量空速6h~(-1)时,烯烃转化率高于90%的时间可达100小时以上。  相似文献   

9.
在铂络合物催化剂的作用下,以高碳数烯烃化合物和含氢硅油为原料,利用硅氢加成反应合成有机硅蜡。研究了原料配比、催化剂用量、反应时间、反应温度对Si-H键转化率和产物运动粘度的影响。确定最佳反应条件为:烯键与硅氢健摩尔比n(C—C):n(Si—H)-1.12:1、铂催化剂用量3.2μg/g、反应温度130℃、反应时间8h。并对合成产物的分子结构进行了红外、核磁表征,结果表明长链烷基已被接枝到聚硅氧烷主链中。  相似文献   

10.
本文为综合利用C_4烃类以扩大芳烃来源探索了新的途径。研究了H-ZSM-5分子筛催化剂的制备条件对C_4烃类芳构化催化效率的影响,以及反应条件对反应产物分布的效应。对C_4烃类在H-ZSM-5分子筛催化剂上的芳构化反应过程进行了初步探讨,并对催化剂的稳定性和再生性能作了初步考察。试验结果表明:分离掉丁二烯后的混合C_4烃类可用作制备芳烃的原料;在常压和反应温度为500~550℃,重量空速为1~1.7(小时)~(-1)条件下,液态烃收率为47~52%(重)。其中总芳烃含量达97~98%,C_6~C_8芳烃占91~93%。尾气主要由CH_4、C_2H_4、C_2H_6和C_3H_8所组成。已失活的催化剂经通空气再生后,活性能完全恢复。  相似文献   

11.
FOR anesthesiologis s ,treatingpostoperativepainhas alwaysbeen a problem.Althoughopioidshave been provedtobe effective,theirsideeffectscouldnotbeignored.With thedevelopmentofscienceand pharmacology,many drugs with aspectsof satisfactoryanalgesicefficacyand couldbe welltoleratedby patientshave been developed.And lornoxicamisone of them, which isa non-steroidalanti-inflammatorydrug (NSAID ), with analgesic, anti-infl-ammatory,andantipyreticproperties.Itseliminationhalf-time(3 to 5 hours) isle…  相似文献   

12.
Dr.Zhang Ren,the chief physician,is the chairman of Shanghai Acupuncture and Moxibustion Association.Having been engaged in medicine for about 40 years,he is experienced in treating various intractable diseases.In his long years of clinical practice,he advocates taking the TCM differentiation as the basis to seek for the acupuncture method for treatment of modern intractable diseases.The author of this essay had the fortune to follow Dr.Zhang in study.The following is a summary of Dr.Zhang's experience in the acupuncture treatment for different intractable diseases with the same therapeutic principle.  相似文献   

13.
In treating chronic nephropathy,Luo Lingjie,a chief physician,pays attention to regulating the balance between yin and yang,treating infection if present,and removing pathogenic factors.He prescribes gentle drugs and uses carefully strongly warming-tonifying ones,emphasizes the importance of persuading the patient to persist in treatment with medication and nurse one's health for recuperation,and is good at combined use of TCM and western medicine therapy and brings the merits of various therapies into full play,with obvious theraoeutic effects.  相似文献   

14.
Objective: To observe the therapeutic effects in acupunture treatment of primary dysmenorrhea combined with spinal Tui Na, and study its mechanism. Methods: Thirty cases of the treatment group were treated by acupuncture combined with spinal Tui Na, and thirty cases in the control group were treated by routine acupuncture. Results: The total effective rate was 93.3% in the treatment group, and 73.3% in the control group, with a significant difference between the two groups (P<0.05). Conclusions: Acupuncture combined with spinal Tui Na has good prospects for treatment of primary dysmenorrhea.  相似文献   

15.
16.
目的 探讨猪肺磷脂注射液联合经鼻持续气道正压通气(NCPAP)对呼吸衰竭早产儿的临床疗效及肌酸激酶同工酶活性(CK-MB)的影响.方法 选取呼吸衰竭早产儿80例,分为观察组和对照组各40例.对照组采用NCPAP给氧治疗,观察组给予NCPAP给氧联合猪肺磷脂气管内给药.观察两组患儿治疗前及治疗12h、24 h后PaO2、PaCO2、血氧饱和度(SaO2)、pH的变化情况,检测治疗前及治疗5d后血清CK-MB水平;评估两组患儿的临床治疗效果.结果 两组患儿PaO2、PaCO2、SaO2、pH比较,差异均有统计学意义(P<0.05),其中观察组治疗后的PaO2、SaO2、pH均高于对照组,PaCO2则低于对照组.两组的PaO2、SaO2、pH均随观察时间延长而升高(P<0.05),PaCO2均随观察时间的延长而降低(P<0.05).观察组治疗有效率为87.5%,显著高于对照组的70.0% (P <0.05).治疗5d后两组患儿血清CK-MB水平均较前降低(P<0.05),且观察组明显低于对照组(P<0.05).结论 猪肺磷脂注射液气管内给药联合NCPAP可以显著降低呼吸衰竭早产儿CK-MB的含量,提高治疗有效率,起到很好的呼吸循环支持作用.  相似文献   

17.
CASE HISTORY A female patient, 46 years old, head of the foreign affairs department of a certain university in Beijing, paid her first visit on October 9, 2006, with the chief complaint of vomiting for one month. She got vomiting after meals in early September. Before that, she had discomfortable sensation in the stomach due to angry with others, but she didn't pay much attention. Later, it developed into vomiting after eating. After the vomiting, the discomfort would be relieved, but with slight hypodynamia. She was once diagnosed as having 'neurogenic vomiting'. Having taken some western and Chinese drugs, the above symptoms were a little bit improved, but she would have nausea upon eating and with regurgitation. Because of the fear for vomiting, she did not dare to have food intake, with body weight reduction of 6 kilos in one month.  相似文献   

18.
Radiotherapy and chemotherapy are the important modern medical therapies for malignant tumors,yet they can also bring about serious local and systemic toxic side reactions so to decrease the patient;'s life quality,manifested by a series of consumptive symptoms.Having engaged in the combined work of Chinese and western medicine for nearly 50 years,the research fellow Qiu Baoguo in Henan Provincial Academy of TCM has developed his unique views on the TCM study of consumptive syndromes.The author of this essay had once the fortune tO follow Dr.Qiu in clinic,and specially would like to introduce in the following Dr.Qiu's experience in treating consumptive syndromes after radio-chemotherapies for patients with malignant tumor.  相似文献   

19.
OBJECTIVE: To observe therapeutic effects of the comprehensive therapy of acupuncture-moxibustion and Chinese Tuina for treatment of insomnia due to deficiency of both the heart and spleen. METHODS: 92 cases were divided randomly into the treatment group (treated by acupuncture-moxibustion and Chinese Tuina) and the control group (treated by acupuncture-moxibustion). RESULTS: The therapeutic effect of the treatment group was obviously superior to that of the control group (the CHI2 test showed P < 0.01). CONCLUSIONS: The comprehensive therapy of acupuncture-moxibustion and Chinese Tuina can give marked therapeutic effects for treatment of insomnia due to deficiency of both the heart and spleen.  相似文献   

20.
Evidence obtained from randomized controlled trials (RCTs) has been generally accepted as the gold standard in the evaluation of clinical effectiveness. Readers need to understand the trial design, implementation, results, analysis and interpretation, so as to fully Jnderstand the results of RCTs. Thus, the investigators of RCTs have to report these items in a complete, accurate and clear manner. Since 1998, we have conducted several evaluations on the reporting quality of RCTs published in Chinese journals on traditional Chinese medicine (TCM) and results have shown that there is an urgent need for higher quality RCTs on TCM.  相似文献   

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