土地利用变化对生态系统碳汇功能影响的综合评价

在分析了六盘山林区典型生态系统碳循环规律的基础上，结合碳汇傈的概念，综合评价了土地利用变化对生态系统碳汇功能的影响。分析得出陆地生态系统碳汇／源功能体现在碳库的贮量、稳定性和碳库的输入与输出强度方面；天然次生林和人工林生态系统的碳贮量汇功能较强，农田和草地较弱；土壤有机碳过程源／汇方面，天然次生林生态系统是强汇，人工林生态系统是弱汇，草地和农田生态系统是源。提出增加生态系统碳汇功能的措施包括增加生态系统碳输入、减少输出和增强碳库的稳定性。     

Influence of processed carbon black in the filler composition on the characteristics of baked carbon mixes

Several carbon products such as carbon brushes, special nuclear carbons, seal rings, etc. require carbon black in the filler composition. In the present study, the raw carbon black was mixed with a coal tar pitch and the resulting carbon mix was shaped, calcined and finally crushed into a fine powder for its subsequent use. The influence of this modified (processed) carbon black in the filler composition on the characteristics of the final calcined petroleum coke, processed carbon black and coal tar pitch-based carbon mixes has been investigated.     

Different solvents for the regeneration of the exhausted activated carbon used in the treatment of coking wastewater

The solvents n-pentane, methylene dichloride, ethyl ether and dodecylbenzenesulphonic acid sodium were used to regenerate exhausted activated carbon used in the process of treating coking wastewater, and the efficiency, ability, and optimum conditions of the different solvents on this regeneration were investigated. The results indicate that n-pentane could effectively remove refractory organic compounds in the coking wastewater adsorbed on the surface of activated carbon and could repeatedly regenerate the exhausted activated carbon to recover its adsorption activity. Under the conditions of a regeneration time of 20 min, a regeneration temperature of 25°C, an activated carbon drying time of 300 min, and an activated carbon drying temperature of 150°C, n-pentane had the best regeneration efficiency, at 98.27%, for exhausted activated carbon. Gas chromatography-mass spectrometry analysis results show that the nature of the activated carbon regenerated by organic solvents had no remarkable change in adsorption for the main types of organic compounds in coking wastewater. The good regenerative effect of n-pentane on the activated carbon may be due its stronger desorption of esters embedded within the internal structure of activated carbon.     

The influence of activated carbon surface properties on the adsorption of the herbicide molinate and the bio-regeneration of the adsorbent

In the present study, the effect of the textural and surface chemistry properties of the activated carbon were evaluated in a combined treatment system to remove the herbicide molinate from waters. The process consists of an initial adsorption step followed by the bio-regeneration of the activated carbon through the utilization of a defined bacterial mixed culture (DC), previously described as able to mineralize molinate. Molinate adsorption and partial bio-regeneration was favoured with activated carbons with larger pores, consisting mainly of meso and macropores. In order to study the effect of different surface chemical characteristics while maintaining the original textural properties, a commercial activated carbon was submitted to thermal and nitric acid treatments. The thermal treatment improved the molinate adsorption capacity of activated carbon. However, the bio-regeneration of the nitric acid oxidised activated carbon was slightly higher. With all the activated carbon materials used it was observed that the biological consumption of molinate present in the liquid phase displaced the equilibrium towards the activated carbon partial regeneration.     

Pin-on-plate studies on the effect of rotation on the wear of metal-on-metal samples

An important cause of osteolysis and subsequent loosening of replacement hip joints is the body's biological response to polyethylene wear debris. Interest has thus been renewed in hard bearing surfaces such as metal-on-metal implants. Tests were performed on a pin-on-plate machine to determine the effects of pin rotation on the wear of two different compositions of cobalt chrome molybdenum (CoCrMo) against itself (high carbon and low carbon). With reciprocating motion only, the low carbon material gave an order of magnitude higher wear than the high carbon material. The overall wear (that for both the pin and the plate) was significantly reduced with added rotation for the low carbon material but remained approximately the same for the high carbon material. However, the wear of the low carbon material was not reduced below that of the high carbon material which remained the best material in terms of wear. © 2001 Kluwer Academic Publishers     

碳纤维表面处理及其对碳纤维/树脂界面影响的研究

碳纤维增强树脂/石墨复合材料是树脂/石墨双极板材料的一个主要研究内容,纤维与树脂间的界面结合是其中的关键问题.综述了碳纤维的氧化处理、偶联剂涂层处理和等离子体处理方法及各种处理方法对碳纤维/树脂界面的影响.对碳纤维的表面处理,可以提高碳纤维与树脂的界面粘接力,获得良好的界面层,达到对界面的优化处理.     

碳相含量对C—SiC—TiC—TiB2复合材料结构和力学性能的影响

研究了碳相含量对原位合成的碳／陶复合材料（Ｃ－ＳｉＣ－ＴｉＣ－ＴＩＢ２）的结构和性能的影响。结果表明：随着碳含量的增加，材料的 度下降，材料的烧结温度应随着碳含量增加相应提高，才能获得致密的碳／陶复全材料。     

Effects of the size of nano-copper catalysts and reaction temperature on the morphology of carbon fibers

In this study, carbon fibers with different morphologies, including coiled carbon nanofibers and straight carbon fibers, were obtained by the chemical vapor deposition using a Cu-catalytic pyrolysis of acetylene at 250 °C. The influences of nano-copper catalyst particle size and the reaction temperature on the morphology of carbon fibers were investigated. Under the same reaction condition, coiled carbon nanofibers generally were synthesized using nano-copper catalyst with smaller particles size, and bigger copper particles are apt to produce straight carbon fibers. With decreasing of reaction temperature to 200 °C, straight carbon fibers were obtained, instead of coiled carbon nanofibers at 250 °C. The product was characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray powder diffraction (XRD).     

Preparation of a silica gel–carbon black composite by the sol–gel process in the presence of polymer-grafted carbon black

This paper is concerned with the preparation of a silica gel–carbon black composite by the sol–gel process, which consists of tetraethoxysilane and polymer-grafted carbon black. Polymer-grafted carbon black was synthesized by three methods: (1) cationic polymerization of N-vinyl-2-pyrrolidone, (2) cationic ring-opening polymerization of 2-methyl-2-oxazoline, and (3) radical polymerization of glycidyl methacrylate followed by reaction of glycidyl groups in the grafted polymer chains with 3-aminopropyltriethoxysilane. The polycondensation of tetraethoxysilane proceeded under acidic conditions in the presence of polymer-grafted carbon black to give a deep black silica gel–carbon black composite. The more the content of untreated carbon black was increased, the more the gelation time was shortened. On the contrary, gelation was retarded by grafted polymer chains on the carbon black surface in the case of polymer-grafted carbon black. The scratch hardness of the resulting silica gel–carbon black composite was almost equal regardless of the carbon black content in the presence of untreated carbon black, whereas it was liable to decrease as the content of polymer-grafted carbon black increased. The solvent adsorption properties of the silica gel–polymer-grafted carbon black composite varied with the solubility of grafted polymer chains on the carbon black surface towards the immersion solvent. © 1998 Chapman & Hall     

Molecular dynamics study of the interfacial strength between carbon fiber and phenolic resin

The interfacial strength between carbon fiber and phenolic resin is studied using molecular dynamics simulations to demonstrate that carbon fiber-reinforced carbon matrix composites (C/C composites) have improved tensile strength. Simulations are performed using two carbon fiber models, one of which has only carbon atoms and the other has carbon atoms and some fluorinated carbon groups. The carbon fiber models are regarded as two-layer graphite, and the phenolic resin model is treated as cross-linked structures. All force field parameters are based on the Dreiding force field. The tensile stress and interfacial fracture energy are calculated for the estimation of the interfacial strength. The results show that the model including the fluorinated carbon groups has lower interfacial strength than the model having only carbon atoms, up to a certain coating ratio of fluorinated carbon groups. Similarly, within the limits of the coating ratio, the interfacial fracture energy of the fluorinated carbon fiber model is lower than that of carbon fiber model having only carbon atoms.     

Carbon in the atmosphere and terrestrial biosphere in the 21st century

The release of carbon dioxide from fossil-fuel combustion and land-use change has caused a significant perturbation in the natural cycling of carbon between land, atmosphere and oceans. Understanding and managing the effects of this disruption on atmospheric composition and global climate are likely to be amongst the most pressing issues of the 21st century. However, the present-day carbon cycle is still poorly understood. One remarkable feature is that an increasing amount of atmospheric carbon dioxide appears to be being absorbed by terrestrial vegetation. I review the recent evidence for the magnitude and spatial distribution of this 'terrestrial carbon sink', drawing on current research on the global atmospheric distribution and transport of carbon dioxide, oxygen and their isotopes; direct measurement of CO(2) fluxes above various biomes; and inventories of forest biomass and composition. I review the likely causes of these carbon sinks and sources and their implications for the ecology and stability of these biomes. Finally, I examine prospects and key issues over coming decades. Within a few years, satellite measurements of atmospheric CO(2) and forest biomass, coupled with 'real-time' biosphere-atmosphere models, will revolutionize our understanding of the terrestrial carbon cycle. Controlling deforestation and managing forests has the potential to play a significant but limited part in reaching the goal of stabilizing atmospheric CO(2) concentrations. However, there are likely to be limits to the amount of carbon storage possible in natural vegetation, and, in the long term, terrestrial carbon storage may be unstable, with the potential to accelerate rather than brake global warming.     

荔枝全程冷链物流碳足迹测算分析及实证研究

目的针对系统衡量双渠道流通模式下荔枝全程冷链物流的碳排放问题,构建一种计算碳足迹模型,以衡量该过程中的碳排放情况,并对其展开实证研究。方法采用碳排放系数法、投入产出法,测算批发商开设的双渠道流通模式的荔枝采后预冷、流通加工、冷藏运输、贮存、配送、销售以及终端消费者等各环节所产生的碳排放量,并借助Matlab对模型进行优化求解,在设定参数的条件下,以及考虑碳排放的情况下,分别以总成本最小和总碳排放量最小进行运算。结果通过实证可知,总成本均为407.34万元,总碳排放量均为223.14t。通过对断链情况下的荔枝双渠道流通模式碳足迹进行对比分析发现,荔枝在断链的流通模式下的总成本为453.99万元,碳排放量为225.71 t;通过对不同包装下的腐损率进行对比分析发现,在考虑碳排放情况下,腐损率从0上升到30%时,碳排放量上升了4%。结论该模型能有效衡量双渠道流通模式下荔枝全程冷链物流活动的碳足迹,为荔枝运用全程冷链物流的经济效益和环境效益最大化协同的设计和实施提供了支撑。     

世界碳纤维的生产与发展

简介了2010年以来世界碳纤维的生产与发展,包括世界主要碳纤维生产商对当前世界碳纤维形势的看法,重点强调了土尔其阿克萨公司的碳纤维发展战略以及对发展我国碳纤维的启示.     

炭材料在水污染修复领域的应用研究

针对炭材料在水污染修复领域发挥的重要作用,对以活性炭(粉状、粒状及纤维状)和膨胀石墨为主的炭材料吸附技术、微生物与炭材料复合构成的生物炭材料吸附降解技术以及二者与其它技术(如臭氧氧化、膜过滤及光催化等)耦合用于水处理的应用研究现状进行了概述,指出新型炭材料(如活性炭纤维和膨胀石墨)吸附技术、生物炭材料吸附降解技术及相关耦合技术极具应用前景,并对今后的研究提出了建议.     

由煤或焦炭制备纳米碳质材料的新进展

评述了以煤为碳源制备富勒烯、纳米碳管、竹节形碳管、铁嵌入的纳米碳棒和由碳包覆的金属纳米粒子等各种纳米材料。认为：等离子体电孤放电法是由煤制备各种纳米碳质材料最常用的方法，随电弧条件及电极性质的不同，所制备的纳米碳质材料可有各种不同形态及结构、由于煤是分子固体而石墨是晶格固体，两种碳源的反应机理有明显不同。在等离子体电弧加热时，煤分解并产生许多具有简单芳烃结构的分子，在纳米碳质材料的形成过程中，这些分子可能作为纳米碳质材料的结构单元，同时原煤中的矿物质在合成过程中也起着重要作用，因此煤本身的性质对纳米材料的制备极为重要。煤是成本低廉且储量最丰富的碳源，将是大规模工业化生产纳米碳质材料最好的碳源之一。     

碳限额及交易下低碳补贴和低碳宣传成本分摊的双渠道供应链联合减排策略

为了研究碳限额及交易下考虑低碳补贴和零售商低碳宣传的双渠道供应链联合减排策略问题,构建由一个制造商和一个零售商组成双渠道供应链,分别建立碳减排补贴与低碳宣传的双渠道供应链集中式决策模型以及无碳减排补贴且无低碳宣传成本分摊、有碳减排补贴但无低碳宣传成本分摊、碳减排补贴且低碳宣传成本分摊的双渠道供应链分散式决策模型,分析其最优决策,并指出政府碳减排补贴、碳减排成本和低碳宣传成本分摊能够实现双渠道供应链协调。研究结果表明,在碳限额及交易下,最优碳减排率、最优低碳宣传水平和双渠道供应链利润与政府补贴比例、低碳偏好对需求的影响系数、低碳宣传对线上消费者需求的影响系数、低碳宣传对线下消费者需求的影响系数都成正向变化关系;最优碳减排率、最优低碳宣传水平和双渠道供应链利润与低碳宣传成本系数、最优碳减排成本系数成反向变化关系;最优碳减排率与碳排放交易价格成正向变化关系,而最优低碳宣传水平、双渠道供应链利润与碳排放交易价格成反向变化关系。     

Effect of Temperature on the Synthesis of SiC Coating on Carbon Fibers by the Reaction of SiO with the Deposited Pyrolytic Carbon Layer

The influence of reaction temperature on the preparation of SiC coating on carbon fibers by the reaction of silicon monoxide with the deposited pyrolytic carbon (PyC) layer has been discussed. With rising reaction temperature, the thickness of SiC layer increases and the SiC grain is coarsening. The apparent activation energy for the synthesis of SiC layer is about 103.3 kJ/mol. The oxidation resistance of carbon fiber can be improved by the SiC/PyC layers significantly. The initial oxidation temperature of the SiC/PyC coated carbon fiber is about 300°C higher than that of the uncoated carbon fiber. The oxidation of the SiC/PyC coated carbon fiber is owing to the diffusion of oxygen through the cracks generated by the mismatch of thermal expansion.     

碳中和目标背景下包装行业发展的对策

目的 为了应对日益恶化的全球气候变化,并实现碳中和的目标,研究低碳化技术在包装行业的应用成为当下至关重要的任务。为了推动包装行业在碳中和背景下的低碳化转型,有必要对现有的低碳化技术进行分类和梳理。方法 从碳减排和碳移除两方面对包装行业已有的低碳化技术进行了研究。综述当前可降解生物塑料和聚合物单体化学循环技术在包装中的应用,介绍了几种清洁能源以及碳捕捉、碳利用和碳储存技术的发展现状。结论 对包装行业而言,实现碳中和的目标还面临着很多挑战。包装行业在推进碳中和目标时要选取与发展适合的低碳能源和碳中和技术。     

On the synthesis of Fe---C compounds under the influence of laser radiation

This paper describes investigations on the synthesis of a layer from an iron and carbon powder mixture under the influence of pulsed laser radiation. It was observed that regions with different carbon concentrations are formed in the alloy. In the regions of high carbon concentration a carbide phase of the Fe_1−xC_x type is formed, where x varies from 0.265 to 0.285. The carbon concentration in the carbide phase depends insignificantly on the concentration of the initial mixture and on the laser irradiation exposure time. In the regions of lower carbon concentration a ferrite is formed, the carbon concentration of which does not exceed 0.2 at.%. Investigations showed that γ-Fe and carbide phases are formed both in the hyperfine form (crystal size, about 30 nm) and in larger (ferromagnetic) forms of the crystals.     

碳纤维表面原位固相协同生长纳米碳管

在碳纤维(CF)表面直接原位生长碳纳米管(CNTs),可有效避免CNTs分散不均的问题,充分发挥二者的优势,对获得高层间性能的碳纤维增强树脂基复合材料(CNTs-CF/EP)具有重要的意义。本文对CF进行表面改性处理,在CF表面负载催化剂粒子,然后通过原位生长法并在助催化剂噻吩的协同作用下,在CF表面固相生长了CNTs。此方法得到的CNTs-CF,不仅有效避免CNTs在基体中的相互缠绕、难以分散等问题。而且由于生长CNTs的碳源主要来自CF,二者结合强度较高,对提高CNTs-CF/EP的层间性能非常有利。借助于SEM、XRD及FT-IR等分析测试手段,研究了催化剂Ni(NO_3)_2·6H_2O浓度对表面长有CNTs的CF的形貌、结构及其性能的影响。结果表明:在适当的催化剂浓度(0.2mol·L~(-1))负载中,CF表面能够生长出结合牢固、垂直生长且均匀分布的CNTs,但力学性能有所下降。