Effect of Nano Carbon Black and Graphite Flake on Properties of Low Carbon Al2O3-C Refractories

Low carbon Al2O3 - C refractories specimens were prepared with tabular alumina （3. 0 - 1.0, 1.0 - 0. 5, 0.6-0.2, ≤0.3, ≤0. 045 and ≤0. 02 mm）, active alumina micropowder （≤2 μm ） and silicon （ 〈≤0. 045 mm ） as main raw materials. Nano carbon black （N220） and natural graphite flake （ 〈≤0. 074 mm ） were adopted as the carbon sources. The specimens were treated at 800, 1 000, 1 200 and 1 400 ℃ under coke embedded atmosphere. The effects of additions of nano carbon black and graphite flake on mechanical properties and thermal shock resistance of the specimens were stud- ied. Their mechanical properties were measured by three- point bending test and thermal shock resistance was de- termined by water quenching method. The phase compo- sition of the specimens was analyzed with X-ray diffrac- tion and microstruetures were observed through FESEM. The results reveal that： （1） the strengths of A1203 - C refractories with these two carbon sources show no big differences when coked at lower than 1 000 ℃ ; when coked at over 1 200 ℃ , the strengths of the specimens with graphite added are much higher than those of the specimens containing carbon black due to much more sil- icon carbide whiskers formed; （2） since the nano carbon black has small particle size, they can be filled into in- terstice of Al2O3 particles to form the nano carbon net- work structure, absorbing and relieving the thermal stressgenerated from expansion and contraction and reducing the thermal expansion coefficient of the specimens, thus their thermal shock resistance is better than that of the specimens containing graphite ; （ 3 ） low carbon Al2 O3 - C refractories with good mechanical properties and excellent thermal shock resistance can be prepared with combi- nation of nano carbon black and graphite flake.

Phase Transformations of Graphite and Carbon Black by Laser with Low Power Density

The structure phase transformations of graphite and carbon black induced by pulsed laser were studied in this paper.Under irradiation with laser beam of 1.06 μm wavelength and power density of 106 W·cm-2,both graphite structure and carbon black structure were changed obviously.The results of Raman analyses and Transmission Electron Microscopy(TEM)observations show that graphite transforms into nanodiamond about 5 nm and carbon black is graphitized.It is demonstrated that graphite is the intermediate phase in the transformation from carbon black to diamond,and graphite is easier to transform into diamond by laser irradiation than carbon black.

Covalently bonded ternary photocatalyst comprising MoSe_(2)/black phosphorus nanosheet/graphitic carbon nitride for efficient moxifloxacin degradation

Covalently bonded bridging between different semiconductors is a remarkable approach to improve the transfer of charge carriers at interfaces.In this study,we designed a ternary heterojunction(MBG)combining of molybdenum diselenide(Mo Se_(2)),black phosphorus nanosheets(Bpn)and graphitic carbon nitride(GCN).Among this MBG of Mo Se_(2)/Bpn/GCN,(i)the covalently bonded bridging effect between Bpn/GCN facilitates directional charge carrier transfer,meanwhile(ii)a Z-scheme heterojunction is formed between Mo Se_(2)/GCN to enhance the separation of photogenerated carriers.Furthermore,(iii)this composite exhibits an increased absorption for visible light.Using this MBG,photocatalytic degradation of over 98%of moxifloxacin is achieved within 20 min,with O_(2)·-confirmed as the primary photocatalytic active species.These findings provide novel insights into the construction of efficient heterojunction by covalently bonded bridging.

Graphite and Graphite-like Materials from Black Shale and Magmatic Ores: Raman Spectroscopy Data

Graphite and graphite-like materials widely are present at black shale and magmatic ores. The nature of these carbon materials (CM) is multifarious. In what cause connects a mineralization with carbon. The great numbers of parameters, namely, the temperature, the pressure, the shear stress, the catalytic species, the host-rock lithology, the time and etc., have an influence on the graphitization process. Accumulations of gold and platinum group elements in black graphite shale and extraction of these metals from rocks depend in considerable degree from structural properties of CM. Raman spectroscopy has wide applied for various carbon modifications, including nano-structuring materials. The first and second-order Raman spectrum have been correlated with changes in the structure of graphite. There is a linear relationship between temperature and Raman R2 and R1 parameters (derived from the area and intensity of the defect band (D) relative to the ordered graphite band (G), respectively). The purpose of the present study is to characterize the rocks and CM from carbon-rich rocks of gold-ore deposits of the black-shale formation and magmatic ores using micro-Raman spectroscopy technique (Horiba Jobin Ivon LabRam spectrometer). Exciting was performed with 325 nm line of He-Cd laser. The graphite and graphite-like samples from many ore deposits of Russia and Kazahstan are investigations. R1 and R2 ratio indicate variable degree of organisation CM in the samples. The results show different spectral variations of CM with metamorphic grade: the well-ordered graphite from magmatic rocks, more - ordered and the disordered less graphitized CM from black-shale ores. For the first time in the world practice the Raman spectroscopy technique has been applied to determine the temperature of graphitizing for CM at gold-ore deposits of the black-shale formation. The temperatures obtained on carboniferous substance for the gold deposits range from 405°С to 280°С. Temperature of CM formation from Pt-low sulphide ores of the Talnakh deposit ranges from 4700C to 6500C. It has been shown that the carbon-rich phases from black-shale and magmatic rocks have various degrees of graphitization and different carbon forms.

碳源对反应烧结碳化硅性能的影响

以炭黑和石墨为碳源,控制碳添加量为10%(质量分数,下同),研究了不同炭黑、石墨比例对反应烧结碳化硅性能的影响。结果表明,当炭黑添加量为4%、石墨添加量为6%时,反应烧结碳化硅的力学性能较佳,此时抗弯强度为251.7 MPa,断裂韧性为4.29 MPa·m^(1/2)。通过XRD检测及对XRD谱进行Rietveld精修,分析发现炭黑添加量为4%、石墨添加量为6%的反应烧结碳化硅中的游离Si含量为24.44%(质量分数),而石墨添加量为10%的反应烧结碳化硅中的游离Si含量为28.57%(质量分数),相比前者游离Si含量较高,减少游离Si的含量可以提高反应烧结碳化硅的力学性能。

Effect of Carbon Source on Crystal Morphology of SiC in-situ Formed in AI_2O_3-Si-C Matrix

Three kinds of Al2O3- Si- C matrix specimens were prepared using tabular corundum powder and Si powder as starting materials,ultrafine flake graphite,nano carbon black,and carbon nanotubes as carbon sources,respectively,to research the effect of micro or nano carbon materials on structure and morphology of formed Si C crystals. The specimens were fired at 1 000,1 200 and 1 400℃ for 3 h in carbon-embedded condition,respectively.The phase composition was studied by XRD and the crystal morphology of Si C was investigated by FESEM. The results show that：（ 1） the amount of Si C increases with the firing temperature rising;（ 2） the in-situ reaction mechanism and the formed Si C crystal morphology vary with carbon source： carbon nanotubes are generally converted into Si C whiskers by carbon nanotubes-confined reaction; Si and nano carbon black react to nucleate quickly,and the nucleated Si C crystals grow evenly in all directions forming Si C particles; Si C whiskers are produced from edge to internal of ultrafine flake graphite.

Low Temperature Preparation of Carbide Coated Carbon for Refractory Castable Applications

Titanium carbide （ TiC ） coated graphite flakes （GF） and carbon black （CB） powders were prepared at relatively low temperatures （ 750 - 950 ℃ ） using a no- vel molten salt synthesis technique. The in-situ formed TiC coatings were homogeneous and crack-free and their thicknesses could be readily controlled/tailored by simply adjusting the Ti/C ratio. Compared to their uncoated counterparts, as prepared TiC coated GF and CB showed much improved water-wettability/dispersivity and rheological properties, and thus could be potentially used to prepare carbon-containing refractory castables.

Effect of Properties of Carbon Materials on Performance of VRLA Batteries

In the present study, the relationship between properties of different carbon materials and their impact on performance of VRLA （valve regulated lead acid） battery was studied. The material properties undertaken for the study are： surface area, conductivity and water absorption of the carbon. The electrode morphology revealed the uniform distribution of active material when high surface area carbon was added to NAM （negative active material）. The porosity of the plate also exhibited changes with respect to type of carbon materials added. The study further revealed that, the addition of high surface area carbon （-1,400 m^2/g） improves the charge acceptance of the battery with higher loading. Further improvement in charge acceptance was observed with addition of graphite to higher surface area carbon. Nevertheless, the float current of the battery got affected due to graphite loading and found there was no impact on shelf life of the battery in all the cases. The study demonstrates the need for customized ＂carbon formulation＂ to obtain the maximum performance out of the battery.

High-Efficiency(Over 10%) Parallel Tandem Dye-Sensitized Solar Cells Based on Tri-Carbon Electrodes

Ensuring high power conversion efficiency,partially or completely replacing Pt electrodes with inexpensive materials is one of the important development directions of dye-sensitized solar cells(DSSCs).In this work,we have developed a threecomponent(MWCNTs,carbon black and graphite) carbon(tri-carbon) electrode material for DSSC devices combined with the advantages of high electron transfer kinetics of MWCNTs,plentiful catalytic sites in crystal edges of carbon black and superior electrical conductivity and catalytic activity of graphite.Using a tri-carbon electrode,a Pt electrode,and two N719-sensitized photoanodes,a parallel tandem dye-sensitized solar cells are assembled obtaining a high PCE of 10.26%(V_(OC)=0.70 V,J_(SC)=19.99 mA/cm~2,FF=73.33%).It opens up a new avenue for the development of low-cost and highperformance DSSCs.

Evaluation and Characterization of Mechanical,Electrical,and Thermal Properties of Polymer Nanocomposites Reinforced with Different Allotropes of Carbon

The present work aims to present the results based on the processing of nanocomposites,which consist of matrix materials like epoxy and filler materials such as conjugated nanomaterials/allotropes of carbon,namely,carbon black,graphite,and multiwalled carbon nanotube(MWCNT)used for targeted applications.To improve the physical and chemical properties and to facilitate a better interfacial interface between the polymer and nanotube,functional MWCNT is used during the preparation of the composite.The prime objective of the study is to establish the thermal,mechanical,and electrical properties of nanocomposites using experimental methods.It has been observed from the experimental results that carbon nanotube(CNT)based composite exhibits higher mechanical(tensile and hardness)and thermal properties as compared with the others.The electrical properties are found to be better in a graphite-based composite.Although CNT has superior mechanical and thermal properties,the exorbitant price limits its use.Hence,the allotropes of carbon may be used judiciously considering both the cost and property requirements of the targeted application.The work also studies the dispersion state of nanofibers through scanning electron microscopy(SEM).

石墨化碳黑净化柱结合HPLC-PDA和LC-MS/MS快速检测苹果汁中展青霉素

基于石墨化碳黑材料制备了一种固相萃取柱(GCB柱),结合高效液相色谱-二极管阵列检测法(HPLC-PDA)和液相色谱-串联质谱法(LC-MS/MS)评估了GCB柱和4种商业化固相萃取柱(Retain AX PAX、MAX和HLB)的净化效果,并对澄清型苹果汁中影响展青霉素准确定量的杂质进行了分析。结果发现,苹果汁经上述5种净化柱净化后,大大降低了杂质干扰,色谱图、信噪比和基质效应显著改善。其中,GCB净化为HPLC-PDA分析提供了理想的色谱图,为LC-MS/MS分析提供了可接受的基质效应(-14%)、优于HLB净化的色谱图以及与Retain AX净化相当的信噪比。建立的稳定同位素稀释-液相色谱-串联质谱法(SIDA-LC-MS/MS)可以克服基质效应和净化损失对检测结果准确性的影响。采用HPLC-PDA和SIDALC-MS/MS分析时,GCB净化比HLB净化的方法更灵敏;MAX、HLB和GCB净化均能得到较好的回收率(82%~102%)和较小的相对标准偏差(≤9%)。所开发的GCB净化方法仅需上样和洗脱2步,且在重力作用下过柱仅需10 min,比其他固相萃取净化更简单快捷,净化能力良好。实际样品经GCB柱净化和HPLC-PDA、SIDA-LC-MS/MS分别分析,展青霉素的平均含量为34μg·kg-1。GCB柱较好的净化效果和较低的使用成本将有助于其在展青霉素常规检测中的广泛应用。

Towards Efficient Electromagnetic Interference Shielding Performance for Polyethylene Composites by Structuring Segregated Carbon Black/Graphite Networks

An electromagnetic interference （EMI） shielding composite based on ultrahigh molecular weight polyethylene （UHMWPE） loaded with economical graphite-carbon black （CB） hybrid fillers was prepared via a green and facile methodology, i.e., high-speed mechanical mixing combined with hot compression thus avoiding the assistance of the intensive ultrasound dispersion in volatile organic solvents. In this composite, the graphite-CB hybrid fillers were selectively distributed in the interfacial regions of UHMWPE domains resulting a typical segregated structure. Thanks to the specific morphology of segregated conductive networks along with the synergetic effect of large-sized graphite flakes and small-sized CB nanoparticles, a low filler loading of 7.7 vol% （15 wt%） yielded the graphite-CB/UHMWPE composites with a satisfactory electrical conductivity of 33.9 S/m and a superior shielding effectiveness of 40.2 dB, manifesting the comparable value of the pricey large-aspect-ratio carbon nanofillers （e.g., carbon nanotubes and graphene nanosheets） based polymer composites. More interestingly, with the addition of 15 wt% graphite-CB （1/3, W/W） hybrid fillers, the tensile strength and elongation at break of the composite reached 25.3 MPa and 126%, respectively; with a remarkable increase of 58.1% and 2420% over the conventional segregated graphite/UHMWPE composites. The mechanical reinforcement could be attributed to the favor of the small-sized CB particles in the polymer molecular diffusion between UHMWPE domains which in tuna provided a stronger interfacial adhesion. This work provides a facile, green and affordable strategy to obtain the polymer composites with high electrical conductivity, efficient EMI shielding, and balanced mechanical performance.

g-C_(3)N_(4)/CB/Au NPs修饰玻碳电极的制备及其对硫酸联氨的电化学测定

将炭黑(CB)纳米粒子与类石墨相氮化碳(g-C_(3)N_(4))混合,然后将金纳米粒子(Au NPs)掺杂其中,形成一种新型g-C_(3)N_(4)/CB/AuNPs复合纳米材料,用于修饰玻碳电极.通过扫描电子显微镜(SEM)对复合材料的形貌进行了表征.实验结果表明:g-C_(3)N_(4)/CB/AuNPs对硫酸联氨(N2H4·H_(2)SO_(4))的电化学氧化呈现极好的电催化性能.硫酸联氨的氧化电流与其物质的量浓度在2.5×10^(-5)~1.5×10^(-3)mol·L^(-1)线性范围内呈良好的线性关系,检测限为1.6μmol·L^(-1)(信噪比S/N=3).

蔬菜中残留农药的石墨化碳黑净化和气相色谱-质谱检测方法

研究石墨化碳黑对不同类型农药的吸附规律和对色素的吸附能力,比较了不同洗脱溶剂对色素的洗脱能力和对待测物在GCB上洗脱顺序的影响。同时测试了GCB和活性炭的吸附-解吸附等温线,表明不同的表面结构造成了两种吸附剂不同的吸附机理及对色素吸附能力的显著差别。结果表明,GCB对含有芳香环、结构具有一定对称性的农药吸附力最强,而对叶绿素吸附强于叶黄素和番茄红素。最后根据实验结果针对性地建立了残留在蔬菜中农药多残留方法：样品经GCB净化,以丙酮/乙酸乙酯（1∶1,V/V）为洗脱液,最后用气相色谱-质谱选择离子存储（GC-MS/SIS）检测,所有农药的检出限保持在0.002-0.10 mg/kg范围内。

碳基吸波材料的研究进展

传统吸波材料由于密度大、吸收频带窄使其应用受到限制,新型吸波材料的探索和研究将会成为吸波材料领域的主要发展方向。碳材料以其独特的物理化学性能一直备受关注。先进碳材料已成为新材料领域的发展重点。碳材料是最早用来吸收电磁波的材料之一,近年来碳基吸波材料的性能不断提高并应用于更多领域。介绍了碳基(石墨、炭黑、碳纤维、碳纳米管)吸波材料的性能,分析了各种吸波材料的主要特点,总结了近年来国内外碳基吸波材料的研究进展及发展趋势,展望了碳基吸波材料的发展前景。

石墨、炭黑替代碳纤维对砂浆力学性能和导电性能的影响

以碳纤维掺量为1％的砂浆为基准，分别用25％、50％和100％的石墨、炭黑替代碳纤维。研究不同替代比例对砂浆力学性能和电阻率的影响，并根据力学性能、导电性能两项指标综合分析石墨、炭黑的最优替代量。试验结果表明：随着石墨、炭黑替代比例的增加，砂浆的电阻率变大；综合力学性能和导电性能确定石墨、炭黑的最优替代量分别为25％、25％～50％。

气相色谱化学电离二级质谱法测定土壤中16种三嗪类除草剂的残留

建立了气相色谱化学电离二级质谱法(GC-CI-MS/MS)同时测定土壤中16种三嗪类除草剂多残留量的方法,测定16种三嗪类除草剂仅需12min。样品采用乙腈与盐酸混合溶液,加入氯化钠超声波辅助提取,离心后,乙腈层经过国产石墨化炭黑(GCB)柱净化,流出液浓缩后环己烷定容,GC-MS/MS测定。研究比较了在不同进样溶剂下的化合物响应和不同填料固相萃取(SPE)柱的萃取净化效果,结果表明,环己烷作为进样溶剂效果最好,国产GCB和C18-SPE柱的回收率较好,同时国产GCB对色素的净化效果好,替代进口SPE柱,可以节约实验成本。16种三嗪类除草剂在0.05(0.1)～8.0mg/L范围内线性良好,相关系数在0.9952～0.9999之间;在0.005～0.02μg/g添加水平范围内,平均添加回收率在91.41%～114.12%之间;相对标准偏差在1.1%～16.8%之间。本方法中16种三嗪类除草剂在土壤中的检出限均低于0.005μg/g。

白炭黑、B_4C改性酚醛树脂粘接石墨高温性能研究

在 B4C改性酚醛树脂 (phenol- form aldehyde resin,PF)高温粘接剂的基础上 ,向其中添加白炭黑 (超细Si O2 )制备新型粘接剂 ,并对石墨材料进行粘接和热处理 ,测试了不同温度热处理后的粘接强度。结果表明 ,2 5 5 0℃处理后新型粘接剂仍具有理想的耐热温度和粘接强度。利用扫描电镜 (SEM)对样品断面形貌进行观察 ,研究了粘接界面的组成和结构变化及其与粘接性能之间的关系。实验结果表明 ,白炭黑的添加 。

等离子体热解焦油制备导电炭黑

用电弧产生的Ar、N2 或空气等离子体热解乙烯焦油制备炭黑 ,检测了所产生的炭黑的物化性能 .X射线衍射和高分辨率透射电镜分析了样品的微观结构 .与乙炔炭黑进行比较 ,这种方法产生的炭黑在微观结构、导电性能、盐酸吸液量、吸油值等方面具有类似乙炔炭黑的性质 .还初步分析了炭黑物化性能、结构之间的关系以及工艺条件对它们的影响 .等离子体制备导电炭黑的电能消耗为每升原料油 1～ 2kWh,在高功率下炭黑样品为纳米石墨粉 .