Intercalation of organic compounds into layered titanoniobate KTiNbO5

Organic intercalations into [TiNbO₅⁻] layers are investigated. Aliphatic amine intercalates were obtained from HTiNbO₅ which was prepared by HC1 treatment of KTiNbO₅. Weak bases such as aminopyridines, 4,4'-azodianiline and spiropyran (SP) were intercalated into the [TiNbO₅⁻] layers from tetradecylamine intercalate. SP intercalate was red and the color disappered by the photo-irradiation.     

Preparation of pillared carbon thin films and their size selective electrical response to organic vapor

Thin films of graphite oxide silylated with octyltrichlorosilane were first prepared and they were further silylated with 3-aminopropyltriethoxysilane. Pillared carbon thin films with an interlayer spacing of 1.7 nm were prepared from the pyrolysis of the resulting thin films. Larger propylene carbonate molecules were not intercalated into them. They showed selective electrical response to electron donating and smaller organic molecules. The increase in the electrical resistance upon exposure to organic molecule seems to be larger for those with larger donor numbers.     

Preparation of pillared carbon thin films from the reduction of silylated graphite oxide by UV light irradiation and their size selective electrical response to various molecules

Silylated graphite oxide thin films were reduced by UV light irradiation using a super high pressure Hg lamp at 95 °C. The reduction of silylated graphite oxide was completed within 24 h and a new pillared carbon with an interlayer spacing of 0.81 nm was obtained. Pillared carbons with larger interlayer spacings of about 1.13 nm were also obtained from graphite oxide silylated with octyltrichlorosilane and then with 3-aminopropyltriethoxysilane for 1.5–6 h, when they were reduced by UV light irradiation and heating at 200 °C under vacuum. Selective electrical response during exposure to gaseous vinylene carbonate, acetonitrile, ozone and hydrogen molecules has been achieved by changing the pillar density in the resulting pillared carbon films.     

Adsorption of organic molecules from aqueous solutions on carbon materials

Adsorption of organic molecules from dilute aqueous solutions on carbon materials is a complex interplay between non-electrostatic and electrostatic interactions. Non-electrostatic interactions are essentially due to dispersion and hydrophobic interactions, whereas the electrostatic or coulombic interactions appear with electrolytes when they are ionized at the experimental conditions used. Both interactions depend on the characteristics of the adsorbent and the adsorptive and the solution chemistry. Among them the carbon surface chemistry has a great influence on both electrostatic and non-electrostatic interactions, and can be considered one of the main factors in the adsorption mechanism from dilute aqueous solutions. In this paper the current knowledge about the fundamental factors that control the adsorption process from aqueous phase will be presented.     

Soil organic carbon contents as a result of various organic amendments to a vertisol

The present study estimates the contributions of various organic amendments to soil organic carbon (SOC). The present work discusses data from a 32-year fertilization experiment using vertisol soil. Five treatments with four field replications were included: no fertilizer (CK), mineral fertilizers only (NPK), wheat straw plus NPK (SNPK), swine manure plus NPK (PMNPK), and cattle manure plus NPK (CMNPK). The ¹³C signature of SOC was measured by δ ¹³C natural isotope technology, and the carbon functional compositions of organic amendments were determined by solid-state ¹³C nuclear magnetic resonance spectra. The average proportions of native and crop residues derived organic carbon under the SNPK, PMNPK and CMNPK treatments were 43, 40, 29, and 51, 51, 39%, respectively. The average proportions of organic carbon-derived from wheat straw (SNPK), swine and cattle manure (PMNPK and CMNPK) were 6, 9, and 32%, respectively. The quantitative relationship between carbon retention efficiency and fertilization year could be described by a significantly negative linear function (p < 0.05). The average organic carbon retention efficiencies for wheat straw, swine, and cattle manure differed substantially at 6, 10, and 31%, respectively. Their corresponding aromatic carbon contents were 6, 7, and 12%, respectively. Furthermore, incorporation of organic amendments, especially for cattle manure, led to a decrease in the yield variability and an increase in the sustainable yield index of crops compared with the CK and NPK treatments. In conclusion, the long-term continuous application of cattle manure is a preferred method for enhancing SOC storage and increasing crop production for vertisols.     

Electrochemical lithium ion storage properties of single-walled carbon nanotubes containing organic molecules

The Li ion storage properties of single-walled carbon nanotube peapods containing one of three organic molecules (9,10-dichloroanthracene, β-carotene, coronene) were measured. It was found by electrochemical charge-discharge measurements that the reversible storage capacity of the SWCNTs significantly increased as a result of the inclusion, although unfortunately the samples are still not appropriate for the practical use as an anode material in Li ion battery because of the high irreversible capacity (>900 mAh/g). In the most effective case, the tube containing the organic molecule can store about 2.5 times more Li ions compared to an empty tube.     

有机柱撑型层状硅酸钠δ-双八的摩擦学性能研究

用四球式摩擦磨损试验机考察有机柱撑型层状硅酸钠δ-双八在100SN基础油中的摩擦学性能,X射线衍射分析样品在实验前、后的变化情况,扫描电子显微镜观察分析磨损表面情况。结果表明,有机柱撑型层状硅酸钠δ-双八能有效地改善100SN基础油的承载能力、减摩抗磨等摩擦学性能,并能够在实验中保持层状结构不变。     

Intercalation properties of the carbon cathode of aluminum reduction cells

The intercalation of cathode carbon and associated disordered carbons by AlCl₃ has been measured by a technique that eliminates surface adsorption and pore condensation. Intercalation by this electron acceptor is greater for the more ordered carbons that have been reported to intercalate less sodium (an electron donor). Measurement of intercalation by AlCl₃ is therefore a useful way of characterizing carbon cathodes. It shows that an anthracite-pitch cathode does graphitize during exposure to the Hall liquid at 900–1000°C.     

Tuning the photophysical properties of soluble single-wall carbon nanotube derivatives by co-functionalization with organic molecules

The photophysical characterization of three soluble derivatives of single-wall carbon nanotubes (SWCNTs), functionalized with poly(ethylene glycol) (PEG), co-functionalized with PEG and aminofluorene and co-functionalized with PEG and aminoanthracene is reported. The peculiar excellent solubility of these derivatives allows, for the first time in covalently functionalized SWCNTs, the study of their excitation dynamics by monitoring the near-infra-red emission. Moreover, the aminoanthracene derivative shows higher photoluminescence efficiency in the visible range than the aminofluorene derivative, demonstrating the possibility to tune extensively the photophysical properties of these functionalized SWCNTs.     

Preparation and characterization of layered carbon hybrid framework materials pillared with titanocene

Novel graphene oxide layered hybrid framework materials pillared titanocene organometallic complex were prepared through a facile ultrasound intercalation approach. The products exhibited periodic layered structures with expanded interlayer spacing as characterized by XRD. Raman spectroscopy demonstrated that the skeleton structure of layered carbon still remained after titanocene treatment. Nitrogen sorption analysis indicated that the building blocks of graphene oxide sheets were cross-linked with titanocene molecules to form lamellar porous structures.     

Self-assembly of organic molecules on montmorillonite

Smectite clays have been modified via ion exchange reactions with organic onium ions for five decades and are of industrial importance in diverse industries including oil well drilling, paint, grease, ink, cosmetics, environmental clean-up, polymer nanocomposites and pharmaceuticals. Over the past decade, a substantial amount of research has been conducted on other methods of organic modification of smectite clays. One method that has seen increased attention is surface treatment via ion–dipole bonding of organic molecules, oligomers or polymers to the exchangeable cation on the clay surface. Utilizing this method, a unique self-assembly of certain organic molecules has been discovered in which the molecules form rigid posts around each cation on the surface. This paper reports a parametric study coupled with molecular modeling of a series of three different families of ion–dipole bonding molecules. The bonding trends and controlling factors in the self-assembly of these molecules are described in detail. In general, it appears that the head group of the molecule is one of the principal factors controlling self-assembly but the chain length of the alkyl group also plays a role.     

金属柱撑黏土催化非均相Fenton技术的研究

金属柱撑黏土(PILC)能够在保证Fenton法对有机污染物的去除功效的同时,较好地克服Fenton法催化剂易流失、适用pH范围小等缺点.介绍了金属柱撑黏土制备的新进展,总结了柱撑黏土单独催化或与紫外等技术联合催化非均相Fenton反应降解水体有机污染物的研究成果,分析了柱撑黏土催化非均相Fenton反应的机理.针对目前研究仍然存在的问题,结合实际应用的需求,提出了今后工作中一些值得关注的方向.     

Atomistic molecular dynamics simulation of liquid carbon tetrachloride confined in pillared pore materials

Atomistic molecular dynamics simulations were performed to investigate the dependence of the self-diffusivity of liquid carbon tetrachloride (CCl₄) confined in pillared pore materials on the pore width, porosity and the surface heterogeneity of the solid walls. The simulated results show that the self-diffusivity of liquid CCl₄ does not increase monotonically with the pore width, but in an oscillatory manner to approach the bulk diffusivity. Moreover, the presence of activated sites characterizing the surface heterogeneity and the pillars reduces the self-diffusivity of liquid CCl₄ confined in pillared pores. The effects of these factors on the self-diffusivity of fluids should be taken into account when a porous nanomaterial is designed or chosen for a certain process, in addition to their effects on other properties such as the adsorption capability.     

Modification of the porosity of pillared clays by carbon deposition. I. Polymer carbonization

In order to use pillared clays (PILC) for selective adsorption, further modifications of the porous structure are necessary. The deposition of carbon residues onto the porous structure of pillared clays by the carbonization of polymers (polyvinylalcohol) was proposed to achieve a controlled modification of the pore size. Ti and Al-pillared clays (calcined and non-calcined) were impregnated with PVA (different grades and different concentrations and subsequently carbonized to form carbon phases. The effect of the carbon deposits on the porosity of Ti- and Al-PILC is discussed in terms of pore-blocking, pore-filling and pore-narrowing. The deposition of carbon using PVA resulted in a complete pore-blocking for Al-PILC and in a narrowing of the pore size distribution for Ti-PILC, without achieving a controlled pore-narrowing.