Search

Reactions of (μ-edt)Fe2(CO)6 (edt = SCH2CH2S) (1) with the monophosphine ligands Ph2PCH2Ph, Ph2PC6H11, Ph2PCH2CH2CH3, or P(2-C4H3O)3 in the presence of Me3NO∙2H2O afforded (μ-edt)Fe2(CO)5L [L = Ph2PCH2Ph, 2; Ph2PC6H11, 3; Ph2PCH2CH2CH3, 4; P(2-C4H3O)3, 5] in 70–88% yields. Complexes 2–5 were characterized by spectroscopy and single crystal X-ray diffraction analysis. The phosphorus of 2–5 is in an apical position of the distorted octahedral geometry of iron.

Ordered microporous carbon materials with controlled chemical and physical properties were synthesized by one-step nanocasting process using different carbon precursors. Large amount of heteroatoms, particularly oxygen and nitrogen species were presented in the carbon matrix. The interactions between the electrolyte ions and the surface functionalities were investigated in detail under various electrolyte environments. The electrochemical studies have revealed that different pseudo-processes occurred in proton-rich and proton-free electrolyte solutions. In proton-rich electrolyte environment, the faradaic processes are mainly due to the proton exchange between the nitrogen and oxygen species on the carbon electrode with the electrolyte. On the other hand, in proton-free electrolytes, nitrogen species was shown to play very important role in terms of the adsorption/desorption of K+ ions when negatively polarized in K+ containing electrolytes. The faradaic interaction between K+ ions and the nitrogen functionalities are stronger at the more negative potential. Very high gravimetric capacitance of 452 F/g and large capacitance retention of 97% at high discharge rate was achieved by the nitrogen-enriched carbon with moderately developed surface area. The superior capacitive performances of the templated carbons are closely linked to the ordered hierarchical porous structure, the adequate microporosity as well as the presence of suitable surface functionalities.

Linearlinking polystyrene nanospheres (LPSs) with uniform size dispersion were synthesized by the emulsifier-free emulsion polymerization method. And with the adding of divinylbenzene (DVB) crosslinking polystyrene nanospheres (CPSs) was also prepared. It was found out that the partical size of prepared nanospheres changed with the continuous increment of added DVB. The sulfonation of resultant polystyrene nanospheres yielded solids with sulfonic acid groups. The relationship between nanospheres material structure and attached acid groups was investigated in detail. It was observed that the amount of added DVB is the main factor which can affect the amount and thermal stability of attached sulfonic acid groups. The catalytic performance of resultant solid acid catalysts was evaluated through the esterification reaction of methanol with acetic acid. Moreover, the prepared sulfonated polystyrene nanospheres show higher acetic acid conversion than the commercial one, therefore the sulfonated nanospheres could be an excellent potential replacement for liquid acid catalyst.

Mesoporous carbons prepared using a templating method under different carbonization temperatures are sulfonated with concentrated H2SO4 . Without the moving of silica template carbon–silica composites were prepared, which can maintain the pore structure well during sulfonation reaction process. The resultant samples are characterized using nitrogen adsorption, transmission electron microscope, field-emission scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, and elemental analysis techniques. The catalytic performances of the sulfonated carbons and composites are evaluated by esterification reaction of methanol with acetic acid. The results show that a low-temperature carbonization process is favorable for improving the reaction conversion of acetic acid. In addition, the sulfonated carbon–silica composites show a higher acetic acid conversion than the sulfonated mesoporous carbons.

Mesoporous carbons prepared using a templating method under different carbonization temperatures are sulfonated with concentrated H2SO4. Without the moving of silica template carbon–silica composites were prepared, which can maintain the pore structure well during sulfonation reaction process. The resultant samples are characterized using nitrogen adsorption, transmission electron microscope, field-emission scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, and elemental analysis techniques. The catalytic performances of the sulfonated carbons and composites are evaluated by esterification reaction of methanol with acetic acid. The results show that a low-temperature carbonization process is favorable for improving the reaction conversion of acetic acid. In addition, the sulfonated carbon–silica composites show a higher acetic acid conversion than the sulfonated mesoporous carbons.

The immobilization of metal nanoparticles in the framework of porous carbon for heterogeneous catalysis may avoid particle aggregation, movement, and leaching, thus leading to a high catalyst efficiency. In this Full Paper, an approach to prepare Ru nanoparticles incorporated into the pore walls of porous carbon to form a sandwiched Ru/C nanostructure for heterogeneous hydrogenation is demonstrated. Physical adsorption of nitrogen, X-ray diffraction, thermogravimetric analysis, field-emission transmission electron microscopy, field-emission scanning electron microscopy, and energy dispersive X-ray spectroscopy techniques are employed to study the structure and morphology of the catalysts. Catalytic results show that the Ru nanoparticles sandwiched in the pore walls of porous carbon display a remarkably high activity and stability in the hydrogenation of benzene. An enhanced hydrogen spillover effect is believed to play a significant role in the hydrogenation reaction because of the intimate interfacial contact between Ru nanoparticles and the carbon support. The catalyst system described in this work may offer a new concept for optimizing catalyst nanostructures.

To observe different effects of moxibustion on extracellular potassium ion in acupoint under physiological and pathological status and provide experimental evidence for exploring action mechanism of moxibustion on acupoint local.Forty female SD rats were randomly divided into a blank group, a blank-moxibustion group, a model group and a model-moxibustion group, 10 cases in each one. The complete Freund's adjuvant(CFA) was adopted to establish model of adjuvant arthritis (AA) in the model group and model-moxibustion group. No treatment was given in the blank group and model group while moxibustion was applied at "Zusan-li" (ST 36) for 30 min in the blank-moxibustion group and model-moxibustion group. The tissue fluid in "Zusanli" (ST 36) was collected with microdialysis and real-time analyzed by electrolytic analyzer. The change of concentration of potassium ion in "Zusanli" (ST 36) was observed.(1) Under physiological status, the concentration of extracellular potassium ion in the blank group was not changed within 150 min (P0.05); before the moxibustion, the concentration of extracellular potassium ion in the blank-moxibustion group was (1.21 +/- 0.31) mmol/L, and after treatment it was gradually increased and reached its peak at (2.38 +/- 0.42) mmol/L after 60 min (P0.05), then it was reduced. 150 min after the treatment, concentration of potassium ion was slightly higher than that before moxibustion as well as that in the blank group. The concentration in the blank-moxibustion group at 60 min was statistically significant compared with that in the blank group (P0.05). (2) Under pathological status, the concentration of extracellular potassium ion in the model group was not changed within 150 min, differences of which at each time point was not statistically significant (all P0.05). Before the moxibustion, the concentration of extracellular potassium ion was (1.09 +/- 0.12) mmol/L in the model-moxibustion group, and it was immediately increased to (1.96 +/- 0.18) mmol/L after moxibustion. 60 min and 90 min after the moxibustion, it still maintained a higher level, which was (1.87 +/- 0.29) mmol/L and (1.59 +/- 0.16) mmol/L respectively (both P0.05). The differences of each time point after moxibustion in the model-moxibustion group were statistically significant compared with those in the model group (all P0.05).The moxibustion could increase the concentration of potassium ion in rat's acupoint local under physiological status but time of effect is short; with moxibustion at "Zusanli" (ST 36) under pathological status, the concentration of local potassium ion is obviously increased and maintains for a long time.

We demonstrate a general approach to the preparation of layered graphene oxide structures with sandwiched conducting polymers of different morphologies. The approach is conceptualized on the basis of the electrostatic interactions between negatively charged graphene oxide sheets and positively charged surfactant micelles. A graphene oxide-polypyrrole composite prepared from this approach exhibited an excellent electrocapacitive performance with a high specific capacitance over 500 F g(-1). Good rate performance and cycle ability were realized by the composite electrode. The simple method described here opens up a generalized route to making a wide range of graphene oxide-based and graphene-based composite materials for applications beyond electrochemical energy storage.

In this study, sulfonated mesoporous carbons by using the templating method were prepared and characterized. The catalytic performance of the as-prepared sulfonated carbon catalysts was examined through esterification of methanol with acetic acid. The results showed that the use of template and lower carbonization temperature favour the catalytic performance.

In comparison with traditional porous carbon materials such as activated carbons and carbon blacks, template-synthesized carbons can more easily and controllably achieve prescribed physical, chemical, and morphological properties for a wide range of novel applications. Our review of this relatively new field has shown that templating on length scales ranging from nanometers to micrometers is readily achievable, enabling one to design and build a desired scaffold of porous carbon. Clearly, a number of issues and challenges must be addressed before such carbons find practical applications. The high cost (because of the involvement of templates such as SBA-15 and MCM-48) and environmental impact (because of the use of corrosive chemicals such as HF and NaOH) represent two key issues. Control of infiltration of carbon into template pores is also a challenge. Nevertheless, we are optimistic that such template-synthesized hierarchical porous carbon structures may soon find applications, especially in emerging high-tech areas such as nanotechnology, biotechnology, and photonics.

Ruthenium (Ru) nanoparticles incorporated into the pore walls of porous carbon was used as a catalyst in glucose hydrogenation to produce sorbitol. In comparison with other catalysts, including commercial catalysts and catalysts prepared using other methods, the Ru-C nanostructured catalyst displayed higher catalytic activity and stability. These effects were associated with the enhanced contact between the Ru nanoparticles and carbon matrix, as well as the unblocked pores of the catalyst.