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1.
为深入认识煤样的快速热解行为,捕捉气体释放特性,在873~1 273 K条件下基于管式反应器对3种不同煤阶的典型煤样开展热解实验研究,借助红外气体分析系统记录在线气体组成。研究结果表明,热解温度的升高,对煤中含氢/含氧官能团的分解有促进作用,当温度自873 K上升至1 273 K时,H2和CO的释放量均增加了4~5倍;在实验范围的高温下,煤阶对热解反应有效气体产物组成的影响较小,在1 273 K时,H2的释放量几乎与煤种无关。  相似文献   

2.
利用管式炉层燃方式研究了燃烧温度、气氛等不同条件对高硫石油焦燃烧过程中多环芳烃(PAHs)生成及其分布的影响,探讨了石油焦特性对生成PAHs种类的影响。研究结果表明,石油焦在空气中燃烧PAHs的生成总量随着实验温度(600~900℃)的升高先增加后降低,在700℃时达到最大值。石油焦在氮气中热解时,PAHs生成规律也是随温度升高先增加后降低,在800℃时达到最大释放值。不同反应温度和气氛下释放的PAHs均以低环芳烃为主。相同燃烧条件下,随着石油焦挥发分质量分数的增加,PAHs生成量总体呈现增加趋势;石油焦中硫元素质量分数的增加会使PAHs生成量减少;随着石油焦中碳元素质量分数的增加,PAHs生成量呈现先降低再增加的变化趋势。  相似文献   

3.
以正己烷为溶剂,考察了热溶温度对红柳林煤(HL)热溶行为的影响,并研究了不同热溶温度下残渣的热解特性。结果表明:随着热溶温度从260℃升高至340℃,热溶萃取的小分子化合物(包括焦油和水的液相产物以及气相产物)的产率逐渐从7.10%增加至11.96%。热溶处理对原煤热解行为的影响显著,经过热溶处理后原煤热解析出的挥发分的产率则从28.02%降至10.49%~21.38%。随着热溶温度从260℃升高至340℃,热溶残渣热解过程中析出物质的产率从21.38%降至10.49%,液相产物的产率从12.01%降至3.72%,气相产物的产率稍有降低。煤中的小分子化合物是煤低温热解过程的"活性"物质,它不仅是化合物热解液相产物的组成部分,还可为煤的主体结构热解供氢,促进煤热解向焦油和气体的转化。  相似文献   

4.
为研究稻草与煤共热解过程中钾元素的迁移规律,选用稻草和晋城无烟煤为原料,在高频炉实验平台上对全钾的析出以及不同赋存状态钾的迁移转化进行了研究。结果表明,晋城无烟煤对钾的析出有抑制作用,全钾析出率随着温度的升高和煤掺混比降低而升高;当热解温度低于1 000℃时,SiO2与钾生成较稳定的硅酸盐;当热解温度高于1 000℃时,高岭土与钾生成稳定的硅铝酸盐。Al2O3通过表面黏附来减少钾的析出,煤中的挥发分和固定碳可以与钾结合减少钾的析出,晋城无烟煤整体上促进了稻草中水溶态和可离子交换态钾向酸溶态及残渣态钾转化。  相似文献   

5.
以山西新峪煤为研究对象,考察了微波功率、微波辐照时间、NaOH质量分数以及液固质量比等参数对煤中有机硫脱除效果的影响,并对微波处理前后煤样的表面官能团和不同形态硫的含量进行了表征。结果表明,微波与NaOH共处理与两者分别单独处理相比,对煤中有机硫有更明显的脱硫作用,较优的共处理脱硫条件为:微波功率385 W,微波辐照30 min,NaOH质量分数10%以及液固质量比10:1,此时脱硫率高达62.66%。微波处理后煤样中不同形态硫的衍射峰强度明显减弱,与此同时煤中脂肪结构的衍射峰强度也有所减弱。煤中不同形态硫通过微波脱除由易到难的顺序为:硫醇和硫醚,砜类,亚砜,噻吩。在上述较优的工艺条件下新峪煤中硫醇和硫醚的脱除率可达89.87%,砜类的脱除率为79.74%,亚砜类脱除率为44.30%,而噻吩类的脱除率仅为14.07%。微波辐照脱除煤中的有机硫的作用机制主要是通过热效应促进NaOH与煤中的有机硫化物发生反应,同时也能促进煤中键能较小的C-S键直接发生断裂。  相似文献   

6.
对我国18种具有代表性的不同煤化程度的煤(Φ3mm),在氢气氛、0.1MPa和900℃条件下进行了热解实验研究。考察了煤化程度对热解转化率和热解产物产率的影响;煤中挥发分与甲烷产率的关系;煤中氧含量与CO、CO2产率的关系以及煤种对热解气热值的影响,得到了描述热解气产率与煤中挥发分的关系式。  相似文献   

7.
考察了城市污泥与神府煤共气化过程中硫元素的挥发行为。结合X射线衍射(XRD)分析与热力学计算,讨论了含磷化合物对硫挥发行为的影响机理。实验结果表明:污泥中磷酸铝可与硬石膏发生反应,使混合物中硫元素在较低温度下挥发出来。当气化温度为900~1 200 ℃时,污泥对硫元素挥发比例影响最为显著。当气化温度为1 000 ℃时,含磷质量分数为0.5%与1.0%的污泥煤混合物中,硫元素挥发比例较神府煤分别上升了19.2%和35.5%。当气化温度高于1 300 ℃时,样品中大部分硫元素挥发出来,污泥对混合物中硫元素挥发比例影响不显著。  相似文献   

8.
采用热重分析法,对神府煤和蓝藻单独热解及共热解(蓝藻掺混比,即蓝藻与干基混合物的质量比为5%, 10%, 20%, 40%和80%)特性进行了研究。研究表明:蓝藻挥发分析出的极值温度比煤低,而且热解速率比煤快。蓝藻组成复杂、挥发分含量高且含有的不稳定键多,所以在较低温度下就会被破坏,从而以较高的速率挥发出去。当蓝藻与神府煤共热解时,低温下蓝藻的挥发分析出后,暴露出来的灰分覆盖在煤的表面,灰分中具有催化作用的碱和碱土金属会加快煤的热解反应,使煤的挥发分提前析出。当蓝藻的掺混比为40%和80%时,协同作用较明显,热解焦的产率比理论值低。  相似文献   

9.
采用热重分析仪研究了云南玉溪煤和新疆准东煤的加氢热解煤焦二氧化碳气化反应性,考察了成焦压力、停留时间及气氛对煤焦气化反应性的影响,并利用均相模型计算了各煤焦的非等温气化动力学参数。采用实验室固定床反应器,研究了上述两种煤加氢热解煤焦的水蒸气气化特性,考察了成焦气氛对煤焦气化速率和气体产物组成的影响。热重气化实验表明,准东煤焦的气化反应性明显好于玉溪煤焦,前者的反应活化能远小于后者的反应活化能;无论哪种煤,加氢热解煤焦的气化反应性随加氢过程碳转化率的增大呈下降趋势;在相近的碳转化率下,加氢热解煤焦的气化反应性明显好于氮气气氛热解所得煤焦。在水蒸气气化的情况下,准东煤焦的气化反应性同样好于玉溪煤焦。总体上准东加氢热解煤焦的产氢率相比氮气气氛热解所得煤焦有所增加,不过对于这两种煤焦,随着气化温度提高,H2与CO的物质的量之比均逐渐接近于热力学平衡所得的计算值。  相似文献   

10.
紫外分光光度法测定复方硫洗剂中硫的含量   总被引:1,自引:0,他引:1  
目的建立测定复方硫洗剂中硫的含量的紫外分光光度法。方法取硫(升华硫)约0.1g,加氢氧化钾-稀乙醇(1→10)溶液10ml,于80℃水浴中加热溶解,用水制成每1ml含硫约100μg的溶液,在370nm(±2nm)波长处测定。结果硫在60~120μg/ml浓度范围内,线性关系良好(r=0.9995),平均回收率为101.3%(n=4),RSD=1.2%。结论紫外分光光度法测定复方硫洗剂中硫的含量结果较满意。  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.
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   

13.
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   

14.
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   

15.
16.
Objective: To investigate if there are the CK-19, PDX-1, Nestin, Ngn3 positive cells in the donor islets of different purity in rats. Methods: Thirty male adult SD rats were randomly divided into 3 groups. Islets were isolated using digestion by ductal injection of collagenase. Group Ⅰ (n=10): Separating cell preparations were not purified, Group Ⅱ(n=10): Islet sediment was purified with 25% Ficoll400 ,Group Ⅲ (n=10): Islet sediment was purified with 25% and 11% Ficoll-400. The levels of protein of CK-19, PDX-1, Nestin and Ngn3 were detected by immunohistochemistry and the mRNA of CK-19, PDX-1, Nestin, Ngn3 was amplified by RT-PCR. Results: After two different purification methods applied, three islet preparations of different purities were obtained. The difference of islet purity was significant among various groups (P<0.05). Compared with group Ⅱ and group Ⅲ,the protein and mRNA of CK-19, PDX-1, Nestin,Ngn3 were both higher in group Ⅰ; group Ⅲ was poorly expressed. Conclusions: The three different islet purity donor islet have different CK-19, PDX-1, Nestin, Ngn3 positive cells within them, indicating that there are some islet stem cells in the purified donor islet.  相似文献   

17.
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   

18.
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   

19.
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   

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