Pre-dispersed carbon black as conductive agent for LiFePO_4 cathodes

High dispersed carbon black was applied for LiFePO4 cathodes as conductive agent.Nano-conductive carbon agent was pre-dispersed with poly acrylic acid(PAA) as dispersant in organic N-methyl-pyrrolidone(NMP) solvent system.The dispersion property of nano-conductive carbon agent was evaluated using particle size distribution measurements,scanning electron microscopy(SEM) and transmission electron microscope(TEM).LiFePO4 cathode with as-received nano-conductive carbon agent(SP) and LiFePO4 cathode with pre-dispersed nano-conductive carbon agent(SP-PAA) were examined by scanning electron microscopy(SEM),cyclic voltammetry(CV),electrochemical impendence spectroscopy(EIS) and charge/discharge cycling performance.Results show that the dispersion property of carbon black is improved by using PAA as the dispersant.The LiFePO4 cathodes with SP-PAA exhibit improved rate behaviors(4C,135.1 mAh/g) and cycle performance(95%,200 cycles) compared to LiFePO4 cathodes with SP(4C,103.9 mAh/g and 83%,200 cycles).Because pre-dispersed carbon black(SP-PAA) is dispersed homogeneously in the dried composite electrode to form a more uniform conductive network between the active material particles,electrochemical performances of the LiFePO4 cathodes are improved.

Black Hole Entropy with Modified Dispersion Relations

There is much interest in resolving the quantum corrections to Bekenstein-Hawking entropy with a large length scale limit. The leading correction term ＆ given by the logarithm of black hole area with a model-dependent coefficient. Recently the research for quantum gravity implies the emergence of a modification of the energy-momentum dispersion relation （MDR）, which plays an important role in the modified black hole thermodynamics. In this paper, we investigate the quantum corrections to Bekenstein-Hawking entropy in four-dimensional Sehwarzschild black hole and Reissner-Nordstrom black hole respectively based on MDR.

Preparation of Waterborne Nanoscale Carbon Black Dispersion with Sodium Carboxymethyl Cellulose

Waterborne nanoscale carbon black dispersion （NCBD） was widely used in inkjet printing, spun.dyeing fibers and coloration fabrics. In this paper, NCBD was prepared using sodium carboxymethyl cellulose （CMC） as dispersant. Effects of CMC viscosity, ultrasonic time and oxidation with hydrogen peroxide on carbon black （CB） particle size were discussed. The results showed that CB particle size decreased by mechanical agitation while it Increased by ultrasonic with the increase of CMC viscosity. Uitrasonk is a more effective method to disperse CB particles than that of mechanical agitation. CB particle size lbviously decreased with itcreasing ultrasonic time and arrived at about 160 nm for 60min.In addition,oxidation with 2 mol/L of H2O2 and 0.2wt% of CMC300 reduced CB particle size to 160nm at 90℃ for 2.5h.

Modified Wave Particle Duality and Black Hole Physics

de Broglie relation is revisited,in consideration of a generalization of canonical commuting relation.Thepossible effects on particle's localization and black hole physics are also discussed,in a heuristic manner.

分散黑S-PN染料有害芳香胺假阳性溯源分析

针对分散黑S-PN染料检出有害芳香胺假阳性问题,采用GC/MS检测技术进行分析鉴别。结果表明,该假阳性检出物实为对氯苯胺的同分异构体(间氯苯胺)。结合TLC和LC/MS检测技术溯源分析间氯苯胺,在分散黑S-PN染料中分离鉴定出分散橙O-44、分散红R-82、分散蓝B-79拼混分散染料,明确间氯苯胺来自O-44,推断分析假阳性源于O-44商品染料的副产物(间氯硝基苯),在检测过程中被还原生成间氯苯胺。

X-Ray and Mössbauer Study of Magnetic Black Sand from Mayotte Island

Natural magnetic black sands are known from several sites often located in areas of volcanic origin. Their elemental and mineral composition provides information on the geology of their territory and depends on several factors occurred during their formation. A sample of black sand was collected on the seashore of the island of Mayotte in the Indian Ocean and its magnetic part was investigated by means of energy dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (XRD), and MÖssbauer spectroscopy at room temperature. The mineral composition is dominantly magnetite, in good agreement with samples collected in other sites of volcanic origin. Contrary to pure magnetite, a relevant fraction of Ti was detected by EDS. The 16% Ti and 1% Mn content increase the magnetite lattice parameter to 8.4312 (25) Å. The broadening of XRD lines pointed towards a significant degree of disorder. This was confirmed by MÖssbauer spectroscopy and is attributed to the presence of Ti replacing Fe in the magnetite lattice. The presence of Ti modifies the local magnetic field on the Fe sites, leading to a broader and more complex MÖssbauer transmission spectrum with respect to the one of pure magnetite. To study the effect of temperature, samples were heated for 12 hours to 600°C and 800°C in argon and to 1000°C in air. Annealing in argon did not improve the crystallinity while annealing in air caused a complete decomposition of magnetite into hematite and pseudobrookite.

Neutron Activation Analysis and Scanning Electron Microscopy of Phytoplankton in the Coastal Zone of Crimea (The Black Sea)

The physiology and ecology of planktonic organisms are influenced by the concentration, chemical speciation and resulting bioavailability of some trace metals. The determination of the elemental structure of phytoplankton is important for interpretation of physiological and functional states of coastal ecosystems. The present study is focused on the structure and elemental composition of the phytoplankton assemblages from the different coastal zones by instrumental neutron activation analysis (INAA), scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). For the first time these complementary techniques were simultaneously applied to study the Black Sea phytoplankton. The concentrations of 45 elements in the coastal phytoplankton communities used as bioindicator of inorganic contamination of the Black Sea coastal area near Sevastopol, Ukraine, were determined. Phytoplankton samples were collected by total tows of the plankton net with 35 μm pore size at 3 stations situated in polluted and relatively pristine water areas of the Sevastopol coastal zone during autumn period of the phytoplankton growth. The concentration of Mg, Al, Sc, Ti, V, Mn, As, Rb, Ba, Th and Fe, Cr increases exponentially from relatively pristine station to more polluted station and 10-times and 3-times greater, respectively, in the phytoplankton of the Sevastopol Bay. The rare-earth elements have relatively the same concentration values less than 1 μg/g and tend to accumulate in the phytoplankton from the polluted station in the Sevastopol Bay. The obtained results are in a good agreement with the elemental concentration data in the oceanic plankton, plankton communities from the White Sea and the Black Sea. Using energy-dispersive X-ray spectrometry the mineral particles of unknown origin and impurities of copper (0.42% by weight) in the phytoplankton at the polluted station and zinc (0.57% by weight) at the relatively pristine station were determined.

ATPB超分散剂的合成及其在ABS/炭黑复合体系中的应用

以端羟基聚丁二烯和N,N-二甲基氨基丙胺为原料,采用两步亲核取代反应制备了含有聚丁二烯骨架和胺基末端结构的端胺基聚丁二烯(ATPB),利用傅里叶变换红外光谱仪、核磁共振氢谱仪表征其分子结构,结果表明,ATPB成功合成并达到预期分子结构。以ATPB为超分散剂,制备了丙烯腈-丁二烯-苯乙烯嵌段共聚物(ABS)和炭黑的复合材料,测试炭黑分散度、分散稳定性和复合材料力学性能。结果表明,合成的ATPB超分散剂对炭黑具有明显的分散效果和较好的分散稳定性,与未经分散的炭黑相比,体系分散度提高了65.8%。复合材料力学性能得到增强,拉伸、弯曲强度分别提升至45.56、78.31 MPa,冲击强度提高了15.7%,其值为7.50 kJ/m^(2)。

加工工艺对聚异戊二烯类橡胶炭黑分散性与力学性能的影响

天然橡胶、异戊橡胶和仿生橡胶的主要成分均为顺-1,4-聚异戊二烯,但在蛋白质和磷脂等成分上存在一定差异.这些差异可能会导致橡胶对混炼工艺的响应不同,使填料在橡胶中的分散性产生差异,进而影响硫化胶的动静态性能.为了探究聚异戊二烯类橡胶在不同混炼工艺下的填料分散性和胶料力学性能变化规律,本文以N220炭黑为填料,研究了天然橡胶、异戊橡胶和仿生橡胶这3种聚异戊二烯类橡胶在4种加工工艺下的炭黑分散性和动静态性能.研究结果表明,天然橡胶和异戊橡胶的填料分散性和力学性能对炭黑混入时间的响应程度更强,而仿生橡胶响应较弱.随着炭黑混入时间的延长,天然橡胶和异戊橡胶的平均聚集体粒径分别从约22和19μm下降到约9μm,下降程度较明显,动静态性能得到提升;而相同工艺条件下仿生橡胶的平均聚集体粒径从约20μm下降到约16μm,且炭黑分散状态较差.另一方面,仿生橡胶对塑炼时间响应更加敏感,延长塑炼时间能够显著降低炭黑的平均聚集体粒径并提升橡胶的伸张疲劳性能.为此,本文设计了较长时间(6 min)塑炼结合混炼的工艺,进一步提升了仿生橡胶的伸张疲劳性能.为了明晰仿生橡胶对混炼和塑炼工艺响应性产生差异的原因,探究了不同加工工艺条件下仿生橡胶门尼黏度和分子量的变化规律,发现适中的分子量以及较窄的分子量分布有利于提升胶料的伸张疲劳性能.

乙烯基非交联电缆屏蔽料性能与分散剂含量关系研究

非交联绝缘材料具有优异的电气机械性能,同时生产能耗少、可回收利用,成为目前电缆绝缘料的研究热点,但与之匹配的非交联半导电屏蔽料的研究还鲜有报道。导电炭黑的分散性对屏蔽料的性能影响重大。文中选用线性低密度聚乙烯(LLDPE)为基体树脂,白油为分散剂,采用熔融共混法制备了非交联电缆屏蔽料。研究了白油含量对屏蔽料中炭黑分散、结晶性能、体积电阻率和机械性能的影响。结果表明添加白油会促进炭黑的分散,但白油含量过大会降低屏蔽料的结晶度,增加其体积电阻率并降低拉伸强度和断裂伸长率。当白油含量为2 wt%时,屏蔽料体积电阻率最小,力学性能最佳。该研究为非交联半导电屏蔽料在乙烯基非交联电缆的应用研究提供了参考。

纳米炭黑的Steglich酯化反应制备及乙二醇分散性

为解决炭黑在乙二醇溶液中难分散的问题,确保炭黑在聚酯纤维原液着色中具有良好的分散性。先通过液相氧化法对炭黑表面进行改性,在炭黑表面引入反应性基团—羧基,并选取合适的氧化炭黑,通过Steglich酯化反应在氧化炭黑表面接枝乙二醇和不同相对分子质量的聚乙二醇。对氧化炭黑和接枝炭黑的表面结构以及在乙二醇溶液中的分散性进行测试与分析。结果表明:氧化仅发生在炭黑表面并未对炭黑造成严重破坏,随氧化时间的延长,炭黑表面羧基含量显著提高,氧化8 h后,其表面羧基含量为0.616 mmol/g;PEG600接枝的氧化炭黑其接枝率在33%以上,最小平均粒径稳定在132.1 nm左右,其能在乙二醇溶液中分散均匀,无聚集体出现,且制备的接枝炭黑具有良好的分散稳定性,其储存稳定性在93%以上,耐热稳定性在92%以上。

Determination of disperse elements in black shale by inductively coupled plasma mass spectrometry

THE elements Se, Te, Ge, Re are easily evaporated out when HClO4, HNO3, HF are used as the opendigestion method. There is a great amount of organic and inorganic carbon in black shale, so it is necessary to use oxide acid （HClO4, HNO3） to digest the samples, and the Cl will interfere the determinationof Se and Ge. In this note we reported a simple digestion method for black shale. The sample was digested with HNO3 and HF in PTFE pressure bomb at 190 for 3 h, the rest HF was reacted with HBO, toprotect the introduction system of ICP-MS. After digestion, the samples were determined directly by ICP-MS. So the recoveries were better than the open digestion method. For 50 mg sample,1.5 mL HNO3 and4 drops of HF can completely dissolve black shale. Inductively coupled plasma mass spectrometry has been successfully used for determination of As,Se, Te, Bi in geological materials. In geological and biological samples, the concentrations of ele-

聚烯烃管材料炭黑分散度测试过程的优化

对聚烯烃管材料炭黑分散度测定过程、数据准确性和分析效率的影响因素进行了讨论,找到了制约炭黑分散度测试的两个重要因素是切片质量和图片识别,对测试过程进行了优化,提高了聚烯烃管材料炭黑分散度测试分析效率和准确度,并收集了部分典型的比对图库,已在生产实际中应用,效果良好。

炭黑的微观结构及其在三元乙丙橡胶中的应用性能

对三种不同工艺方法制备的同一牌号炭黑(N550)进行了微观结构和宏观物理机械性能进行研究。采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)等检测方式,分析三种炭黑聚集体在结构和粒径分布等微观结构上的区别。对比了三种炭黑的微观结构及应用过程中分散状态的差异,并且探究了其在三元乙丙橡胶(EPDM)中物理机械性能和制品加工性能的差别。结果表明,炭黑粒径小,原生粒子之间黏连程度低,炭黑的分散性、补强效果更优,胶料的流动性好,在加工过程中能耗低。

炭黑填充硫化胶的补强指数及其影响因素研究

研究炭黑的比表面积、结构和分散状态对硫化胶补强指数[300%定伸应力与100%定伸应力比(M300/M100)]的影响。结果表明:相同结构炭黑的比表面积越大,其填充硫化胶的M300/M100越大;相同比表面积炭黑的结构越低,其填充硫化胶的M300/M100越大;同一炭黑,分散越好,其填充硫化胶的M300/M100越大;当使用M300/M100考核炭黑-橡胶相互作用时,必须在炭黑具有相同的比表面积、结构和分散状态的前提下进行;炭黑填充硫化胶虽然可用反相气相色谱和结合胶含量来表征炭黑-橡胶的相互作用,但M300/M100简单易得,可在有限条件下使用。

干煤粉气化黑水处理药剂的选择和应用

基于干煤粉气化装置的黑水处理工艺及其循环灰水的特性,分析了絮凝剂和分散剂对气化黑水、循环灰水的作用机理和作用效果;通过不同种类的絮凝剂和分散剂的添加效果对比,筛选出了适合干煤粉气化工艺的絮凝剂和分散剂;在试验确定的两种添加剂适宜的添加量条件下,处理后的循环灰水总溶固质量浓度<3500 mg/L,总硬度(以CaCO3计)<1500 mg/L,全碱度<10 mmol/L,悬浮物质量浓度<40 mg/L;气化装置运行周期延长至200 d以上,检修周期缩短至18 d,降低了药剂的消耗成本。

原液着色UHMWPE纤维用炭黑色浆的制备工艺

探讨了不同种类炭黑、超分散剂的选择及用量对炭黑色浆分散稳定性的影响,优化了炭黑色浆的工艺配方,并对色浆的可纺性进行验证,分析了炭黑粒子在纤维中的粒径大小、分散状态和相容性。结果表明:以质量分数为10%的4#炭黑和质量分数为20%的超分散剂A所制备出的炭黑色浆具有良好的耐热贮存稳定性,颜料粒子尺寸可达到纳米级别,且与超高分子质量聚乙烯(UHMWPE)纺丝原液相容性好;该色浆适用于原液着色UHMWPE纤维的生产。

炭黑表面改性技术及其研究进展

炭黑是现代工业中必不可少的原料,但由于其表面的极性基团很少,表面极其不活泼导致炭黑在应用时存在与基体相容性差、粒子分散性不佳、易于团聚等缺点,严重限制了其在各个领域的应用,所以对炭黑粒子进行表面改性是必要的。因此本文以炭黑表面改性为侧重点,详细叙述了炭黑表面接枝改性、表面氧化改性以及分散改性的方法、机理以及研究现状,以期待为未来炭黑粒子表面改性技术提供更多可能性。

碳黑在仿肌肤粉末涂料中的分散性及黑度改善探索

通过对比不同碳黑、聚酯树脂、丙烯酸树脂、填料、流平剂、颜料分散剂及挤出工艺对无光仿肌肤粉末涂料涂层表面状况、黑度的影响;采用调整配方和工艺,改善碳黑在粉末涂料中的分散性,从而得到4%~8%光泽范围内黑度最高的涂层。

炭黑-石墨烯杂化材料增强天然橡胶复合材料的性能研究

利用炭黑颗粒掺杂石墨烯得到炭黑-石墨烯纳米杂化粒子,经乳液复合制备炭黑-石墨烯/天然橡胶母胶,然后通过密炼制得炭黑-石墨烯/天然橡胶纳米复合材料,研究掺杂体系内炭黑用量对炭黑-石墨烯/天然橡胶复合材料的微观形貌、力学性能、压缩生热性能和耐磨性能的影响。结果表明:炭黑颗粒吸附在石墨烯表面,有效抑制了石墨烯的堆叠,从而减少了大片径多层石墨烯的形成,且随着炭黑用量的增大,石墨烯的裸露区域逐渐减少;当掺杂体系中炭黑/石墨烯用量比为10/1时,石墨烯在橡胶中的分散状态得到明显提升,复合材料的宏观力学性能、压缩生热性能和耐磨性能均明显改善。