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New rhenium bipyridyl complexes with dipyrromethene-BF

A new hybrid system is proposed to capture CO2 as well as generate electricity with the low CO2 inlet condition of confined space. Within the system, a novel photocatalytic porous framework coated by g-C3N4/TiO2 is prepared to avoid the inhibition of microalgae growth caused by the direct addition of photocatalyst. Under 0.8% v/v CO2 inlet condition, chemical oxygen demand (COD) yields from the photocatalytic framework immersed in the phosphate buffer and the algae suspension are 1.63 mg L−1 h−1 and 1.90 mg L−1 h−1, respectively. CO2 sequestration rate of a 60L cylindrical photobioreactor increases from 12% to 22%. The combination modes between photobioreactor and photocatalytic framework can be selected flexibly depends on the demands of application. This hybrid system not only benefits to enhance the CO2 sequestration rate of photobioreactor but also has the potential to be served as the power source in a confined space.

A photoactive porphyrinic metal-organic framework (MOF) has been prepared by exchaning Ti into a Zr-based MOF precursor. The resultant mixed-metal Ti/Zr porphyrinic MOF demonstrates a much improved efficiency for gas phase CO 2 photoreduction into CH 4 and CO under visible light irradiation using water vapor compared to the parent Zr-MOF. Insightful studies have been conducted to probe the photocatalysis processes. This work provides the first example of gas phase CO 2 photoreduction into methane without organic sacrificial agents on a MOF platform, thereby paving an avenue for developing MOF-based photocatalysts for applications in CO 2 photoreduction and other types of photoreactions.

Forest thinning is a major forest management practice worldwide and may lead to profound alterations in the fluxes of soil greenhouse gases (GHGs). However, the global patterns and underlying mechanisms of soil GHG fluxes in response to forest thinning remain poorly understood. Here, we conducted a global meta-analysis of 106 studies to assess the effects of forest thinning on soil GHG fluxes and the underpinning mechanisms. The results showed that forest thinning significantly increased soil CO2 emission (mean lnRR: 0.07, 95% CI: 0.03–0.11), N2O emission (mean lnRR: 0.39, 95% CI: 0.16–0.61) and decreased CH4 uptake (mean Hedges’ d: 0.98, 95% CI: 0.32–1.64). Furthermore, the negative response of soil CH4 uptake was amplified by thinning intensity, and the positive response of soil N2O emission decreased with recovery time after thinning. The response of soil CO2 emission was mainly correlated with changes in fine root biomass and soil nitrogen content, and the response of soil CH4 uptake was related to the changes in soil moisture and litterfall. Moreover, the response of soil N2O emission was associated with changes in soil temperature and soil nitrate nitrogen content. Thinning also increased the total balance of the three greenhouse gas fluxes in combination, which decreased with recovery time. Our findings highlight that thinning significantly increases soil GHG emissions, which is crucial to understanding and predicting ecosystem-climate feedbacks in managed forests.

In this study, a pot experiment was carried out to examine the effects of high CO以小麦持绿型品种‘烟农19'和非持绿型品种‘旱选3号'为试材,在开放式气室(OTC)内设置正常CO

Described for the first time is that carbon dioxide (CO2 ) can be successfully inserted into aryl C-H bonds of the backbone of a metal-organic framework (MOF) to generate free carboxylate groups, which serve as Brønsted acid sites for efficiently catalyzing the methanolysis of epoxides. The work delineates the very first example of utilizing CO2 for heterogeneous C-H activation and carboxylation reactions on MOFs, and opens a new avenue for CO2 chemical transformations under mild reaction conditions.

Summary Plans are underway to introduce green transportation systems at Taiwan's famous scenic spot, Sun Moon Lake, to reduce carbon emissions. Carbon reduction effects after changing the current lake tour modes are assessed using a nested logit model with a stated preference survey, which investigated tourists' choice preferences. The empirical results reveal that the modes of electric bus, electric vehicle sharing, and bike are clustered in the same competitive group. Travel cost, in-vehicle travel time, and out-vehicle travel time are found to be statistically significant with the expected negative effects. In particular, the attribute of carbon reduction is only significant for green tourists, who are willing to pay US$ 3.5/kg of carbon saved. The result indicates that more efficient carbon reduction is possible by restricting the usage of gasoline vehicles rather than improving the service levels of low-carbon modes. Notably, the effect of parking charges on emission reduction is equal to the amount of carbon dioxide absorbed by 4511 trees per day. Copyright © 2016 John Wiley & Sons, Ltd.

Commercial activated carbon has been activated with KOH in order to investigate the effect of textural characteristics on CO2storage behaviors. The KOH activation has significantly enhanced the textural properties of the adsorbents, as compared to the pristine sample. CO2adsorption tests on the activated carbons were measured at 298 K and pressures up to 5.0 MPa, and the Langmuir-Freundlich isotherm was used to fit the adsorption data. The CO2uptake for the resulting adsorbents was significantly higher than that of the starting adsorbent in the studied pressure range. To better understand the structures and their influences on the CO2uptake, fractal analysis was conducted for the adsorbents on the basis of Frenkel-Halsey-Hill (FHH) equation. Fractal dimensions (D1and D2) that calculated from N2adsorption data were discussed. The results showed that the two fractal dimensions have different influences on CO2adsorption capacity. There was a negative linear correlation between CO2maximum uptake and D1, while CO2adsorption capacity increased with fractal dimension D2increasing. Therefore, it was concluded that appropriate pore structure fractal dimension with narrower PSDs within the microporous range had higher CO2adsorption capacity for the adsorbents.

Nickel/carbon nanotubes (Ni/CNTs), Nickel/alumina (Ni/Al2O3), calcium-promoted Ni/CNTs and calcium-promoted Ni/Al2O3 were synthesized by impregnation method. Methanation of carbon dioxide was used as a probe to evaluate their catalytic performance. The features of these Ni-based catalysts were investigated via XRD, H2-TPR, H2-TPD and the N2 adsorptiondesorption isotherms. H2-TPR showed that nickel species on Ni/CNTs was reduced more easily with respect to that on Ni/Al2O3, and addition of Ca can increase the content of easily reducible Ni species for Ni/CNTs. XRD and H2-TPD indicated that addition of Ca promoted dispersion for CNTs-supported catalyst. These finding ultimately enhanced catalytic activity and stability for Ni/CNTs catalyst modified with Ca.

This work attempted to recover high-value substances such as free fatty acids, tocopherols, sterols, and squalene by investigating a supercritical fluid CO 2 (SF CO 2 ) distillation-extraction processing of soybean oil deodorizer distillate. Experimental conditions varied between 50 and 90 °C, at 24.1 and 31.0 MPa. Reverse-phase high-performance liquid chromatography analysis was performed to analyze 14 components in the extracts after SF CO 2 treatment. Experimental results indicated that when tocopherols were extracted at 31.0 MPa, 90 (top) to 70 (bottom) °C, and 1000-L STP CO 2 usage, their recovery reached 83.6% and the average value of the concentration factor was 1.38. Furthermore, the concentration factor of tocopherols grew to 1.70 when the extracts collected in the top exceeded 400-L STP CO 2 . The concentration factors of fatty acids, squalene, and stereols were 1.37, 1.26, and 0.60, respectively. This investigation also found that the percentage of total fatty acids decreased, while polyunsaturated fatty acids increased, with an increase in the CO 2 volume given the same extraction condition.

In this work an apparatus is described with which VLE equilibrium data for CO2+linoleicacid, CO2+α-tocopherol, and CO2+triolein over a wide range of pressures and temperatures are obtained. Liquid and vapor densities for these systems were separately measured using a system consisting of two vibrating tube densitometers. A P–x–y diagram of each system was determined at 313 K and 333 K, and pressures up to 24.21 MPa. Linoleic acid is the most soluble compound in CO2 at both temperatures and exhibits the greatest distribution coefficient. At constant temperature, the solubility of each compound in the vapor phase increased with increasing pressure.

This study investigated high-pressure carbon dioxide extractions of crude oil from Anoectochilus Formosanus Hayata (AF), a Chinese herb, and Oolong tea, the most popular healthy materials in Taiwan, individually. Two absorption stages were used to dissolve the solutes, which precipitated from high-pressure CO 2 solution. CO 2 flow rate, particle size, and co-solvent additions were tested to increase the extraction efficiency by using a densitometer to determine the total solute concentration in the absorptive solution. According to those results, both crude oils from these two plant materials and polyphenols of Oolong tea increased with the ethanol content of the co-solvent.

A porous metal-metalloporphyrin framework, MMPF-2, has been constructed from a custom-designed octatopic porphyrin ligand, tetrakis(3,5-dicarboxyphenyl)porphine, that links a distorted cobalt trigonal prism secondary building unit. MMPF-2 possesses permanent microporosity with the highest surface area of 2037 m(2) g(-1) among reported porphyrin-based MOFs, and demonstrates a high uptake capacity of 170 cm(3) g(-1) CO(2) at 273 K and 1 bar.