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1.
以玻璃纤维毡为基质,在玻璃纤维上涂布聚乙烯醇和氯化锌的混合物,得到多孔碳纤维前驱体。通过控制活化条件、改变活化剂浓度以及原料的配比,制备了一系列复合型纤维状多孔炭材料(GFAC),结果显示,活化温度、活化时间和ZnCl2的浓度强烈影响GFAC的比表面积、孔径分布和在玻璃毡上的碳层含量。在450℃的低温下制得的复合材料的比表面积达650m^2/g,中孔体积达65%.空气与ZnCl2共同活化,比在N2气氛中活化更能提高碳层的比表面积,可制得微孔比表面积达75%,比表面积达到400m^2/g的GFAC。GFAC样品具有较好的机械强度,其动态吸附速率接近ACF。 相似文献
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活性碳纤维作为一种性能优良的吸附材料,在环境保护方面有着极其重要的应用,但传统的活性碳纤维都是微孔型的,这就造成了活性碳纤维在应用上的局限,利用自己开发的一种超细固体颗粒加入到纺丝溶液中,然后合理控制碳化、活化温度成功开发出了平均孔径在4.2nm的中孔型的活性碳纤维,其中大于2nm的孔占50%以上,并用VB12对其吸附性能进行了测试,结果表明该活性碳纤维的吸附能力达到1325.35mg/g,用美国麦克公司产ASAP2000型自动吸附仪对比表面积进行了表征,比表面积达到1635.24m^2/g。 相似文献
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中间相沥青的调制对纳米级微孔超高表面积活性炭性能的影响 总被引:3,自引:0,他引:3
以中间相沥青为原料,采用KOH活化制取了超高表面积活性炭,其比表面积高达3464m^2/g,总孔容积高达2.14m^3/g,碘吸附值为3094mg/g,苯吸附值为1610mg/g.所制活性炭富含发达的微孔,其孔径主要集中在1~4nm范围内,具有优异的吸附性能.研究了中间相沥青调制对纳米级微孔超高表面积活性炭性能的影响,结果表明,制备中间相沥青所用原料的净化处理是制备超高表面积活性炭的关键,以1~2℃/min升至400℃并保温2~3h所得中间相沥青制取的活性炭具有极高的吸附性能,中间相沥青炭物料的碳质微晶结构对超高表面积活性炭制取起着决定性作用。 相似文献
4.
研究了沥青不熔化纤维的碳化、活化规律,分析讨论了各因素对沥青基活性碳纤维成型过程的影响。结果表明,要获得较高比表面积的活性碳纤维,不熔化纤维氧化增重应适当,碳化温度宜在750~800℃,获得较大无定形碳的碳纤维。活化温度、活化时间、活化剂浓度也为影响沥青基活性碳纤维比表面积的主要因素。 相似文献
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沥青基活性碳纤维研究:(II)沥青纤维的碳化及活化 总被引:1,自引:1,他引:0
研究了沥青不熔化纤维的碳化、活化规律,分析讨论了各因素对沥青基活性碳纤维成型过程的影响。结果表明,要获得较高比表面活性碳纤维,不熔化纤维氧化增重应适当,碳化温度宜在750 ̄800℃,获得较大无定形碳的碳纤维。活化温度、活化时间、活化剂浓度也为影响沥青基活性碳纤维比表面积的主要因素。 相似文献
7.
超级电容器用沥青焦基活性炭的制备及其电化学性能 总被引:14,自引:9,他引:14
采用沥青焦为原料,制备了系列高比表面积活性炭作为超级电容器电极材料。用直流循环充放电、循环伏安及交流阻抗等表征方法比较了沥青焦基超级活性炭和日本可乐丽公司YPl5活性炭的电化学性能。实验结果表明在KOH、H2SO4、(C2H5)4NBF4/碳酸丙烯酯(Propylenecarbonate PC)及(C2H5)4NBF4/乙腈(Acetonitrile)体系中,沥青焦基活性炭的比电容随比表面积增加,其最高值分别为257F/g、228F/g、140F/g、142F/g,均超过了日本活性炭。沥青焦基活性炭电极在KOH体系中的等效串联电阻的体积电阻率与日本炭相差不大;在H2SO4体系中的电阻率均小于日本活性炭;在碳酸丙烯酯体系中的电阻率均大于日本活性炭;在乙腈体系中,活化剂KOH与沥青焦比例为4:l、经800℃活化3h制备的活性炭的电阻率小于日本活性炭。 相似文献
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一类新型催化剂载体材料的制备研究 总被引:2,自引:0,他引:2
用共沉淀法制备了NZP族磷酸盐类催化剂载体材料,着重研究了煅烧温度度不同的栽体化学组成对其物相、比表面积和孔结构的影响。所制备的载体通过BET氮吸附法(BET)、X射线衍射(XRD)以度透射电镜(TEM)对其进行了表征。结果表明:用共沉淀法制备NZP族栽体的合适的煅烧温度为700℃至900%,此娄栽体的比表面积在10m^2/g至40m^2/g之间,煅烧温度对载体的物相结构和比表面积有很大影响。 相似文献
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以中间相沥青为前驱体,经自挥发发泡法、KOH活化法制备的中间相沥青基活性泡沫炭作为超级电容器电极材料。采用扫描电镜、X射线衍射和低温(77K)N2吸附法对中间相沥青基活性泡沫炭的表面形貌和微观结构进行表征。中间相沥青基活性泡沫炭的比表面积为2700m2/g,总孔孔容为1.487cm3/g。通过恒流充放电、循环伏安和交流阻抗测试,考察了中间相沥青基活性泡沫炭作为超级电容器电极材料的电化学性能。在电流密度为0.02A/g时,中间相沥青基活性泡沫炭的比容量为240.48F/g,能量密度为33.4Wh/kg;在电流密度为5A/g时,比容量为166.68F/g,具有良好的电化学特性。 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
14.
A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.…… 相似文献
16.
Steffen Müller-Probandt 《材料科学与工程:中英文B版...》2018,(4):161-177
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di... 相似文献
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Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß. 相似文献
18.
Janet Lang 《Materials and Manufacturing Processes》2017,32(7-8):857-866
ABSTRACTThe production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them. 相似文献
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C. Qihong W. Zhan‐Wen J. Yi J. Yehua L. Fei F. Hanguang 《Materialwissenschaft und Werkstofftechnik》2014,45(7):582-590
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill. 相似文献
20.
Dimiter Hadjistamov 《材料科学与工程:中英文B版...》2019,(2):56-65
The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ... 相似文献