酚醛树脂炭/石墨复合炭材料用作锂离子电池负极材料的考察

用不同的方法在石墨的表面包覆上一层酚醛树脂 ,然后在 N2 保护下 10 0 0℃炭化 1h制得复合炭材料 ,并用扫描电子显微镜 (SEM)对其表面物理形态进行观察分析 ,研究了复合炭材料的恒电流充放电性能。包覆在石墨表面的具有无定形结构的酚醛树脂炭能够有效阻止石墨在充放电过程中发生层状剥落 ,从而提高复合炭材料的循环稳定性 ,其中通过沉淀法制得的复合炭材料 (CPG- 30 )在十次循环后可逆容量为 32 6 m Ah· g- 1 ,比石墨高 45m Ah· g- 1 ,并保持了首次可逆容量的 96 .2 %。

Calcium titanate corrosion inhibitor enabling carbon as inert anode for oxygen evolution in molten chlorides

The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in molten salts was investigated through various analytical techniques,including linear sweep voltammetry,X-ray diffraction,scanning electron microscopy,and energy dispersion spectroscopy.The results demonstrate that the addition of CaTiO_(3)corrosion inhibitor efficiently passivates the carbon anode and leads to the formation of a dense CaTiO_(3)layer during the electrolysis process in molten CaCl_(2)-CaO.Subsequently,the passivated carbon anode effectively undergoes the oxygen evolution reaction,with an optimal current density for passivation identified at 400 m A/cm^(2).Comprehensive investigations,including CaTiO_(3)solubility tests in molten CaCl_(2)-CaO and numerical modeling of the stability of complex ionic structures,provide compelling evidence supporting“complexation-precipitation”passivation mechanism.This mechanism involves the initial formation of a complex containing TiO_(2)·nCaO by CaTiO_(3)and CaO,which subsequently decomposes to yield CaTiO_(3),firmly coating the surface of the carbon anode.In practical applications,the integration of CaTiO_(3)corrosion inhibitor with the carbon anode leads to the successful preparation of the FeCoNiCrMn high-entropy alloy without carbon contamination in the molten CaCl_(2)-CaO.

Production of carbon anodes by high-temperature mould pressing

Laboratory-scale carbon anodes were produced by a new method of high temperature mould pressing, and their physico-chemical properties were studied. The influence of mould pressing conditions and coal pitch addition on the bulk density, crushing strength, and oxidation resistance was analyzed. The mierostructure of carbon anodes was investigated by scanning electron microscopy （SEM）, and the mechanism of producing carbon anodes by high-temperature mould pressing was analyzed. The results show that when the anodes are produced by high-temperature mould pressing, coal pitch can expand into the coke particles and fill the pores inside the particles, which is beneficial for improving the quality of prebaked anodes. The bulk density of carbon anodes is 1.64-1.66 g/cm3, which is 0.08-0.12 g/cm3 higher than that of industrial anodes, and the oxidation resistance of carbon anodes is also significantly improved.

Recycling of waste carbon residue from spent lithium-ion batteries via constant-pressure acid leaching

Waste carbon residue(WCR)was efficiently detoxicated and regenerated to high-purity graphite(PGC)used in lithium-ion batteries through the constant-pressure acid leaching technique.The leaching conditions were optimized by the combination of orthogonal and single-factor experiments.Results show that PGC with 99.5%purity is regenerated at temperature of 60℃,initial acid concentration of 12%,leaching time of 180 min,and liquid-to-solid ratio of 25:1,satisfying the requirements of commercial graphite.Meanwhile,the sodium hydroxide precipitation process was designed to recover valuable components from leachate efficiently.Ni,Co,Mn,and Al recoveries reach 96.92%,87.5%,97.83%,and 92.17%,respectively,at pH=11.Moreover,the co-product NaF can be recovered with purity over 99%via evaporative crystallization.The loss rate of fluorine is less than 0.5%,thereby eliminating the pollution risk of fluorine to the environment.The proposed process shows considerable environmental and economic benefits.

Catalytic graphitization of polyacrylonitrile-based carbon fibers coated with Prussian blue

Prussian blue(PB) was used as catalyst to improve the extent of graphitization of polyacrylonitrile(PAN)-based carbon fibers.PB was deposited on carbon fibers by anodic electrodeposition and the thickness of PB coating(PB content) was controlled by adjusting the electrodeposition time.PAN-based carbon fibers with PB coating were heat-treated and the extent of graphitization was measured by X-ray diffractometry and Raman spectroscopy.The results indicate that the extent of graphitization of PAN-based carbon fibers is enhanced in the presence of the coating.When the PB-coated carbon fibers were heat-treated at 1 900 ℃,interlayer spacing(d002) and crystallite size(Lc) reach 0.336 8 and 21.2 nm respectively.Contrarily,the values of d002 and Lc are 0.341 4 and 7.4 nm respectively when the bare carbon fibers were heat-treated at 2 800 ℃.Compared with the bare carbon fibers,PB can make the heat treatment temperature(HTT) drop more than 500 ℃ in order to reach the same extent of graphitization.Furthermore,the research results show that PB content also has a certain influence on the extent of graphitization at the same HTT.

Carboniferous–Permian marine transgressions in the Jiyang Depression

In recent years, great attention has been paid to oil and gas exploration in the Carboniferous-Permian strata of the Bohaiwan basin, especially the Carboniferous-Permian marine transgression, using data from drilling, outcrops and carbonate acid-insoluble residue experiments together with the tectonic evo- lutionary history of the peripheral orogenic zones of the North China plate and the Tan-Lu fault zones. The .＇;tudy concludes that marine transgressions took place on six occasions during Carboniferous-Perm- ian time in the Jiyang Depression. The marine transgressions were concentrated in the Late Carbonifer- ous： two marine transgressions occurred in the early Late Carboniferous, and the scale of the first was smaller and the time was shorter than those of the second. The other four marine transgressions hap- pened in the late Late Carboniferous, the first and the fourth of which were larger in scale and longer in time than the second and the third. The seawater came from the Jiaobei area, the eastward part of the Qinling-Dabie residual sea basin, and invaded progressively as a planar flow from south to north and from east to west. These findings have great significance for thorough analysis of the sedimentary characteristics and evolution of the Carboniferous-Permian strata in the livang Denression.

Study on the base-level cycle and the sedimentology of Permian in Jiyang area

The identification of sequence boundaries is the key point for sequence stratigraphic classification. Both the higher-order sequences and the units within the sequences are bounded with the key sediments or isochronous surfaces. Eight sequences can be divided in the whole Permo-Carboniferous strata （the Shiqianfeng Formation is not included）, which is from the Benxi Formation, Taiyuan Formation, Shanxi Formation, Xiashihezi Formation, Wanshan Section, and Kuishan Section to the Xiaofuhe Section. Also, different system tracts （Iowstand system tract, transgression system tract and highstand system tract） and some parasequences can be recognized in each sequence. Parasequence analysis was on the basis of the division of the base-level cycle. The base-level cycle was mainly identified according to the change of the water area, which was reflected by the depositional sequence. The physical characteristic of the strata was reflected by the well log. It was supplied by the test of the minerals and rocks and the analysis of the micro-element in the lab. The paleogeographic characteristic of the Iowstand system tract in the sequence Ⅵ is that the east-north part takes the river system as its feature; the south part is the lake system, the river channel spreads from north to south, and the area of the flooding plain is great. The paleogeographic characteristic of the water-transgressive system tract is that the range of the lake in the south extended distinctively, the range of the river channel in the east reduced. The coastal shallow lake deposit is the main characteristic in the water-transgressive system tract. The paleogeographic characteristic of the highstand system tract is similar to the one of the Iowstand system tract.

Characterizations of Abandoned Peatlands from Acadian Peninsula： Agro-ecologic and Environmental Value-Added Alternatives

In the northeast region of New Brunswick, the majority of peatlands are mainly used for horticultural purposes. Abandoned peatlands after peat extraction could represent one of the most important ecological resources through their remaining substrates： serving as agronomic, ecological or environmental value-added support to local development; and giving a second economic life to peatlands. To evaluate this innovative peat soil management, a study was conducted on three residual peatlands from the Acadian Peninsula. Their status was described through a physic-chemical characterization. The results suggest that the peat thickness and the mineral horizon characteristics are good indicators to identify these post-harvest peat soils. The studied sites were characterized by a flat topography, poor and unequal drainage inducing a variation of the water table level. The peat thickness ranged from 18 cm to 40 cm, while the thickness of the mineral horizon--mostly sandy--ranged between 20 cm and 30 cm. The chemical properties revealed an electrical conductivity above 50 μS·cm^-1, an acid pH, and a variable cation exchange capacity （1.3 cmolc·kg^-1 to 11.4 cmolc·kg^-1）. This preliminary study gives basic knowledge on Acadian Peninsula abandoned peatlands soils and gives information about the conditions of their agro-economic, ecological and/or environmental management.

About A New Complex Method of Climates Reconstruction and Forecasting of Climate Changes in the Future

This paper deals with a new integrated method of reconstruction and forecasting of climatic changes in future. The method is based on proxy data pollen-spore analysis method, 14C analysis method, nowadays meteorological data, and data about of solar activity expressed in numbers of W （Wolf）. Here we present the results of investigation of sediments of the 2nd Fomich River terrace, Taymyr Peninsula, Russia. The formation of the peat bog started 10500 ± 140 years BP and continued during the entire Holocene. The pollen analysis of the sediment samples of the 2nd Fomich River terrace and the analysis of surface samples from a larch forest, typical of this region, reveals two phytochrones： both climatically preconditioned--tundra phytochrone （I1-4） and forest phytochrone （Ⅱ1-4）. The techniques of reconstruction and forecasting of basic elements of climate are presented and discussed in details.

Porous carbon matrix-encapsulated MnO in situ derived from metalorganic frameworks as advanced anode materials for Li-ion capacitors

Conversion-type anode materials hold great potential for Li+storage applications owing to their high specific capacity,while large volume expansion and poor electrical conductivity limit their rate and cycling performances.Herein,a bimetal ZnMn-based metal-organic framework(ZnMn-MOF)is engineered for in situ conversion of MnO-encapsulated porous carbon(MnO/PC)composite.The templating and activation effects of coordinated Zn endow the converted PC matrix with a highly porous structure.This enhances the compatibility of PC matrix with MnO particles,resulting in the full encapsulation of MnO particles in the PC matrix.More significantly,the PC matrix provides enough void space to buffer the volume change,which fully wraps the MnO without crack or fracture during repeated cycling.As a result,MnO/PC shows high charge storage capability,extraordinary rate performance,and long-term cycling stability at the same time.Thus MnO/PC exhibits high delithiation capacities of 768mA h g^(-1)at 0.1Ag^(-1)and 487mA h g^(-1)at a high rate of 0.7Ag^(-1),combined with an unattenuated cycling performance after 500 cycles at 0.3Ag^(-1).More significantly,MnO/PC demonstrates a well-matched performance with the capacitive activated carbon electrode in a Li-ion capacitor(LIC)full cell.LIC demonstrates a high specific energy of 153.6W h kg^(-1)at 210W kg^(-1),combined with a specific energy of 71.8W h kg^(-1)at a high specific power of 63.0kW kg^(-1).

Enhanced electrocatalytic oxidation of dyes in aqueous solution using cobalt phthalocyanine modified activated carbon fiber anode

Cobalt tetra（2,4-dichloro-1,3,5-triazine）aminophthalocyanine （CoPc） was immobilized covalently on activated carbon fiber （ACF） felt to obtain CoPc-modified ACF （CoPc-ACF） catalyst, and an electrocatalytic oxidation system using CoPc-ACF as the anode was constructed. The electrocatalytic oxidation of Acid Red 1 （ARI） was investigated in aqueous solution by an UV-vis spectrophotometer and UPLC. The results indicated that AR1 could be eliminated efficiently in this electrocatalytic oxidation system. In addition, the results of FTIR, TOC and GC-MS suggested that the electrocatalytic oxidation experienced the decoloration achieved by destroying the azo linkage and the further mineralization due to the cleavages of benzene ring and naphthalene ring. The intermediates were mainly small molecular compounds such as maleic acid and succinic acid, etc. Re- petitive tests showed that CoPc-ACF can maintain high electrocatalytic activity over several cycles. The further EPR spin-trap experiments indicated that the hydroxyl radicals did not dominate the reaction in this electrocatalytic system, which was com- pletely different from the traditional electro-Fenton system. Based on the non-radical reaction mechanism, the CoPc-modified ACF electrocatalyst has potential application in treating actual dyestuffs wastewaters, which are accompanied with high concentration of hydroxyl radical scavengers such as chlorine ions and additives in the textile printing and dyeing industry.