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1.
采用农业废弃物玉米芯作为原材料,通过生物碳化(HTC)的方法在不同温度下制备低成本、高性能吸附剂用生物炭.该生物炭具有介孔结构,表面含有丰富的含氧官能团,如—OH,C==O,C—O等,其种类及密度受水热温度的影响.以亚甲基蓝(MB)作为模型吸附剂,进一步研究了生物炭的吸附性能.吸附动力学研究表明符合拟二级动力学模型吸附行为,且225 ℃水热条件下得到的生物炭具有最大吸附量(41.37 mg/g)和最高吸附速率.等温吸附平衡数据与Langmuir等温模型吻合较好,表明生物炭对MB的吸附是单层吸附;生物炭表面含氧官能团与MB分子相互作用有助于吸附过程.  相似文献   

2.
为解决农业资源废弃物作物秸秆的综合利用及水体农药污染问题, 以玉米秸秆为原料, 采用水热炭化法制备水热炭, 并利用扫描电子显微镜(SEM)和Fourier变换红外光谱(FT-IR)法对玉米秸秆水热炭的表面形貌和官能团进行表征, 通过实验室模拟研究不同pH值、 离子强度、 初始浓度以及制备温度对玉米秸秆水热炭吸附水中阿特拉津的影响. 结果表明: 随着温度的升高, 水热炭产生炭微球结构和丰富的含氧官能团; 水热炭对阿特拉津的吸附动力学符合准二级动力学方程(R2≥0.970, P≤0.001), 吸附热力学符合Langmuir方程(R2≥0.992, P≤0.001), 为非线性吸附且自发进行的吸热反应; 玉米秸秆水热炭对水中阿特拉津最大吸附量(298 K)为8.862 mg/g, 最大去除率为69.74%; 水热炭对阿特拉津的吸附量随制备温度的升高而增加, 吸附量随溶液pH值和离子强度的增加而下降. 因此, 利用玉米秸秆制备的水热炭可有效吸附水中的阿特拉津, 具有较好的应用前景, 实验结果为玉米秸秆再利用和水体净化提供理论依据和数据支持.  相似文献   

3.
在CVD增密前对预制体炭纤维进行表面硝酸氧化处理,研究不同浓度硝酸、不同氧化处理时间对炭纤维表面结构状态的影响,以及最终对CVD热解炭微观结构的作用及机理.研究结果表明:对炭纤维表面用质量分数为66%浓硝酸处理时,炭纤维表面形成沿纤维轴向的沟槽;随着处理时间的延长,沟槽先加深后减弱,经40min处理后炭纤维表面刻蚀沟槽最均匀;预制体经不同硝酸质量分数(66%,33%和22%)处理40 min后进行CVD沉积得到C/C复合材料,其中经33%硝酸处理的样品中所沉积的热解炭微观有序度最高,且近炭纤维表面处热解炭有序度最高,由内至外有序度逐渐降低;在优化处理条件下,纤维表面氧化刻蚀均匀,表面所形成的含氧官能团(羰基和羧基)有效诱导了CVD过程中热解炭在纤维表面的有序沉积.  相似文献   

4.
通过硝酸氧化处理对椰壳类活性炭(AC)进行酸化改性,研究酸化条件(温度、时间、浓度)对AC酸值的影响,并考察不同酸值的AC对PP(聚丙烯)/NiO/AC复合材料成炭的影响。采用比表面积及孔径分析仪考察改性活性炭的比表面积及孔结构;以Beohm滴定实验、X射线光电子能谱(XPS)表征改性AC表面含氧官能团种类及含量;用马弗炉、扫描电镜(SEM)考察不同酸值的AC和NiO协效催化聚丙烯成炭及成炭结构。实验结果表明:硝酸处理后,AC比表面积和孔结构均有所变化;酸化条件对AC表面酸性官能团的含量影响显著,改性后表面酸性官能团含量明显增加,酸性官能团主要为—COOH、—CO和—OH;AC表面酸性官能团的增多促进了聚丙烯自身成炭能力,改善了残炭结构。  相似文献   

5.
金属盐类对玉米芯水热炭化过程的影响   总被引:1,自引:0,他引:1  
以生物质玉米芯为原料,研究水热炭化法制备生物炭技术特点.在180~230℃水热条件下,分别以水、氯化铝和氯化锌溶液为液相进行了生物炭化过程实验,检验了温度和液相因素的影响,使用元素分析、傅里叶红外光谱、扫描电子显微镜等技术对生成生物炭的化学及结构变化特性进行了分析和表征.所得生物炭产率为30.3%~50.12%,碳含量为44.26%~63.72%、C/O为0.89%~2.08%、C/H为7.26%~14.19%,热值为17.14~24.37 m J/kg.与水相比,在金属盐类溶液中较低的温度下可生成有较高碳含量和热值的生物炭,在环境扫描电镜中发现该类生物炭呈现较多的球形结构,其中氯化铝对生物炭化过程影响显著.研究为生物质的水热碳化过程合理化提供技术参考.  相似文献   

6.
在高压微波条件下制备了具有特殊表面结构的SAPO-5分子筛微球,研究了模板剂用量对分子筛微球表面大小及形貌的影响,通过X射线衍射(XRD)、扫描电镜(SEM)进行了表征.实验结果表明,模板剂对分子筛微球的合成具有结构导向作用,且模板剂的用量对分子筛微球的聚集状态影响很大,模板剂的用量比在2.00~2.60范围时,生成由粒径为5μm左右的大粒径SAPO-5分子筛的晶体;当模板剂的用量减少到1.12~1.30时,生成由粒径为2~3μmSAPO-5分子筛小颗粒组成的18~25μm微球.  相似文献   

7.
文章采用水热硝酸氧化法对活性炭表面基团进行处理,考察了水热温度对活性炭的孔结构、表面含氧基团的影响,对催化剂进行了一系列表征,并评价了Pd/AC催化剂催化甲酸分解的性能。结果表明,随着水热温度的提高,活性炭上含氧基团先增加后减少,水热温度过高会破坏活性炭孔结构,使Pd粒子尺寸先减小后增大,同时催化剂活性先升高后降低。硝酸浓度为1.0mol/L,水热4h,水热温度为150℃时,催化活性最好;在甲酸浓度为0.01mol/L,90℃反应1h情况下,催化甲酸分解率达到92.2%。  相似文献   

8.
以水稻秸秆为材料,在不同温度下缺氧焙烧制备生物炭.进行FT-IR分析和比表面积测定;利用生物炭对模拟镉污染废水进行吸附试验.结果显示:制备的生物炭含有较多的含氧官能团,且比表面积较大;焙烧温度越高、时间越长,制备的生物炭吸附性能越强,但产率较低.综合分析可知,600℃下焙烧1 h制备生物炭经济合算,吸附效果良好,比表面积可达177.1 m2/g,对废水中Cd2+的去除率接近90%.  相似文献   

9.
将制备的水热改性活性炭纤维负载Ni(Ni/GSACF)作为催化剂,催化碳酰肼还原去除水中的溶解氧(DO),考察反应时间、反应温度、初始pH值、碳酰肼质量浓度和催化剂质量浓度对DO去除效果的影响.在优化条件下,45 min后水中的DO质量浓度从5.1 mg·L-1降至0.1 mg·L-1,去除率可达98.0%.对载体和催化剂进行表征分析,水热处理后GSACF表面的含氧官能团明显增加,催化剂表面具有均匀分散的活性Ni物种.研究结果表明:活性炭纤维表面含氧官能团的增加有利于促进活性Ni物种在活性炭纤维表面的分散,从而提高Ni/GSACF催化剂的催化除氧性能.  相似文献   

10.
采用化学镀的方法在中间相炭微球的表面镀覆金属银,通过扫描电镜分析镀银后炭微球的表面形貌,利用X射线衍射对试样进行物相分析.将镀银的中间相炭微球用作锂离子电池负极材料,测试其电化学性能.研究结果表明:金属银镀覆在中间相炭微球的表面,随着镀银含量的增加,镀银中间相炭微球的首次放电容量升高,银含量16.5%的中间相炭微球的首次放电容量升高12.6mA·h/g;在湿度为25%的气氛中搁置12h后,未镀银的炭微球的放电容量降低16.3mA·h/g,循环稳定性变弱,20次循环后容量保持率为74.6%,而镀银量为16.5%炭微球的首次放电容量只降低6.1mA·h/g,并且循环稳定性强,20次循环后容量保持率为95.8%,说明镀银后中间相炭微球在潮湿条件下的电化学性能得到改善.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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