CO2 Gasses Research Articles

Preparation of supported-deep eutectic solvent membranes: Effects of bath medium composition on the structure and performance of supported-deep eutectic solvent membrane for CO2/N2 gas separation

Polyvinylidene fluoride-co-polytetrafluoroethylene, PVDF-co-PTFE polymer was used as a membrane support. The asymmetric membranes were formed by immersion of casted membrane film into the coagulation bath. This work manipulated the coagulant bath medium by mixing ethanol with distilled water at different weight percentages (0, 25 and 50 wt. % of ethanol). The structures of fabricated membranes were observed to have different morphologies. Higher ethanol content altered the membrane structure from finger-like to sponge-like structure, and hence differed in membrane porosity. Vacuum-based technique was chosen to impregnate the deep eutectic solvent (DES) into the pores of membrane support. DES was prepared by mixing choline chloride (ChCl) and ethylene glycol at a ratio of 1:3. Scanning electron microscopy (SEM) was used to study the membrane morphology changes while in order to determine the immobilization of DES, energy dispersive X-ray (EDX) analysis was used. The porosity of fabricated PVDF-co-PTFE membrane was determined by means of gravimetric method. Lastly, the membrane separation performance using CO2 and N2 gasses were used to determine the capability of the supported-DES-membrane. The results demonstrated the highest immobilization of DES in supported membrane pores was achieved when combination of 25 wt. % of ethanol and 75 wt. % distilled water was used as a coagulant bath medium. The respective membrane has 74.5% porosity with the most excellent performance of CO2 separation at 25.5 x 103 GPU with CO2/N2 selectivity of 2.89.

CO2 emission management in palm oil industries in Indonesia: a review

Within a few decades, Indonesia has become the largest palm oil-producing country, leaving Malaysia behind. It is undeniable that palm oil has significantly contributed to the economic growth of the country. However, the negative impacts of the palm oil industry are also evident, such as deforestation, environmental pollution, and social conflicts. The palm oil industry has been known as one of the big greenhouse gasses producers, including CO2. Regardless of the pressure from the European Union, the Government of Indonesia (GOI) has committed to sustaining the palm oil industry since there are millions of workforces depend on their livelihood from these industries. Concerning the negative impacts, the GOI requests that each palm oil company has to follow the Indonesian Sustainable Palm Oil (ISPO) certification. So far, around 20% of all palm oil industries in the country have received an ISPO certificate. It is expected by 2023, all palm oil industries have been certified by ISPO since this regulation is mandatory. Implementing all ISPO guidelines in the palm oil industry is not only capable of sustaining the industry but also protecting the environment through the reduction of CO2 and other greenhouse gasses. This paper will review the CO2 management in the palm oil industry in Indonesia in the present situation, connected with ISPO as well as RSPO (Roundtable Sustainable Palm Oil).

Karakteristik Emisi CO2 Tanah Gambut di Bawah Tegakan Kelapa Sawit

Penelitian ini bertujuan mengkaji karakteristik emisi CO2 dari tanah gambut di bawah tegakan kelapa sawit yang dihubungkan dengan faktor lingkungan spesifik lokasi penelitian di daerah Kabupaten Labuhan Batu, Sumatera Utara. Gas CO2 diambil dengan menggunakan close chamber technique, sedangkan konsentrasi gas tersebut diukur menggunakan portable micro Gas Chromatograph CP 4900. Faktor lingkungan sebagai variabel bebas yang diamati meliputi suhu tanah (TS), suhu atmosfer (TA), kelembaban tanah lapisan 0 – 5 cm (SM5), kelembaban tanah lapisan 0 – 30 cm (SM30), dan pH gambut (A). Model hubungan CO2 dengan faktor dianalisis menggunakan analisis korelasi Spearman dan regresi multivariant. Analisis regresi multivariant dilakukan menggunakan regresi stepwise untuk mengetahui faktor lingkungan yang mempunyai hubungan dengan CO2 pada taraf beda nyata 5%. Analisis variance inflation factor (vif) dilakukan untuk melihat multicollinearity dari model regresi multivariant. Berdasarkan analisis korelasi Spearman, faktor lingkungan A (pH gambut) mempunyai koefisiensi korelasi yang tegolong sedang (R = 0.637). Hasil regresi stepwise menunjukkan bahwa emisi CO2 nyata dipengaruhi oleh kelembaban tanah SM30 dan A (n = 216; p < 0.05) dengan nilai vif <3. Regresi multivariant, menghasilkan persamaan terbaik (R2 = 0.420) dimana emisi CO2 = 7.394*A – 0.008*SM30 – 16.659. Secara parsial, penelitian ini juga memperoleh model hubungan emisi CO2 dengan kelembaban tanah gambut, dimana emisi CO2 tertinggi dicapai pada kondisi kelembaban tanah sekitar kapasitas lapang (354 – 376% w w-1) dan menurun dengan meningkatnya kelembaban tanah di atas kadar air kapasitas lapangan. Emisi CO2 tanah gambut mengalami penurunan pada kondisi tanah gambut mengering di bawah zone kadar air kritis, hal ini karena hidrofobisitas tanah gambut meningkat.

EFFECTS OF PEBAX COATING CONCENTRATIONS ON CO2/CH4 SEPARATION OF RGO/ZIF-8 PES MEMBRANES

The biggest challenge surrounding application of polymeric membranes for gas separation is their trade–off between gas permeation and selectivity. Therefore, the use of mixed matrix membranes (MMMs) comprising inorganic materials embedded into a polymer matrix can overcome this issue. In this work, PES flat sheet membrane and MMMs consists of 10 wt.% of rGO/ZIF-8 hybrid nanofillers were fabricated via dry/wet phase inversion process. Dip‐coating technique was then used to deposit PEBAX selective layer onto the surface of rGO/ZIF-8 PES support. The effects of PEBAX coating solution concentrations (2, 3 and 4 wt.%) on the permselectivity of CO2 and CH4 were investigated. The as-prepared rGO/ZIF-8 nanofillers and MMMs were characterized by fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (SEM) prior to gas separation performance study. Gas permeation testing was carried out at operating pressure of 1, 3 and 5 bar using CO2 and CH4 gasses. It was observed that the prepared PES membranes and rGO/ZIF-8 PES MMMs did not have any selectivity towards the gases although their permeability was high. As the concentration of PEBAX coating solution increased, thicker coating layer was formed. Therefore, the permeability of CO2 rapidly dropped but the CO2/CH4 selectivity increased significantly up to 38.4. Results indicated that the use of 2 wt.% of PEBAX was not effective to form homogenous coating layers on PES membrane and to cover any defects on membrane surfaces, thus, possessing low selectivity of CO2/CH4. The high gas separation performances obtained in this work was due to the synergistic effect rGO and ZIF-8 crystals. In the rGO/ZIF-8 MMMs, the dispersibility are enhanced due to the presence of distorted rGO sheets, while the ZIF-8 component ensure the porosity of the nanofillers and permit gas interactions with the metallic sites and functional groups on the organic linker. These sites facilitate the reactive adsorption leading to enhanced CO2 adsorption as compared to CH4.

Waste management in integrated waste management facility (TPST) of Piyungan to achieve climate resilience through local institutions

Greenhouse gases (GHG) such as CH4 and CO2 are emitted from wastes at the Piyungan Integrated Waste Management Facility. Integrated Waste Management Facility is called as Tempat Pembuangan Sampah Terpadu in Indonesian, and abbreviated as TPST Piyungan. Both CH4 and CO2 gasses are potential to trigger climate change. Therefore, local institutions are required to intensify efforts towards preventing the harmful effect on climate change. This study aimed to determine the involvement of local institutions in handling waste problems in the TPST as one of the strategies to mitigate climate change. A qualitative approach was used to identify three factors of climate resilience including urban systems (infrastructure), social agents (stakeholders), and local institutions while quantitative scoring methods were used, based on the recommendations from the Intergovernmental Panel on Climate Change (IPCC), to determine the waste management strategies. The results showed the Integrated Waste Management Facility in Piyungan has not been able to reduce CH4 emissions. The urban systems or infrastructure of the facility were found to be in a moderate while the social agents or stakeholders and local institutions were in a good category. However, the participation of local institutions has a major influence on climate change mitigation.

The Treadmill of Information

The world is facing a crisis of global warming due to the release of CO2 and other greenhouse gasses by human activities. Many scholars and stakeholders argue that information and communication technology (ICT) development will mitigate CO2 emissions. Advocacy of technological solutions to CO2 mitigation is consistent with ecological modernization theory's assertion that reflexive societies will modernize sustainably. In contrast, we define the “treadmill of information” as the unique contribution of ICT development to environmental degradation. We examine the impact of ICT development on total CO2 emissions and source-sector emissions from electricity, buildings, manufacturing, and transportation using a multilevel growth model for panel data from 113 countries split into the world, developed country, and less-developed-country samples. We find that the level of fixed telephone development is a strong predictor of higher CO2 emissions in less-developed countries, while internet use predicts higher CO2 emissions in developed countries. The effect of mobile telephone development is not significant. Thus, it appears that ICTs are not having an ameliorative effect on global warming as expected by ecological modernization theorists, and instead reinforce the treadmill of production's negative effect.

OPTIMALISASI COMPOSIT ABSORBER PADA MUFFLER UNTUK MENURUNKAN KADAR EMISI GAS BUANG MOTOR BENSIN

The problem of air pollution caused by burning of fossil fuels and the process of combustion is increase. Many efforts. has done to reduce the air pollution problem. Starting from the combustion process to give equipment as reduce gass emissions and raise the quality of burning, but the ari pollution is still high, especially the burning gasoline of motor fuel Air pollution a motor vehicle exhaust gases come from the rest of the results of the combustion of fuel that do not be unraveled or burning with perfect. Bad gass emissions caused by incomplete combustion of fuel in the fuel chamber. Element contained in the exhaust gasses are CO, NO2, HC, C, H2, CO2, H2O dan N2, The CO and CO2 gasses is the most radical among the others. The CO gass is poisonous, if a men inhale this gas can caused death. While the CO2 gass is a radical gass who can cause the greenhouse effect. The aims of this research are : 1 to understand the effect of carbon composite material, lime and glue towards reductions in emission of motor vehicle . 2. to find out the optimal composition of composite material to reducing the emission level of motor vehicle.The study and research in order to reduce gas emissions until now have done using installation catalyst on muffler. In this research, the mixed of absorption exhaust gas is observed. Especially the poisonous gas. The mixture material is made from carbon, lime and glue. And then installed on muffler filter. A mixture is made by comparation varied. Using minitab software for analyse and the conclusions are: 1. The addition of absorben composition between carbon (C) with lime (CaO) on exhaust can reduce the level of gass emission. 2. The most optimal composition absorben C and CaO in absorption and produce the lowest C and CO2 gass is C and CaO with comparison ratio is 30 %: 70 %

High cell-potential and high-rate neutral aqueous supercapacitors using activated biocarbon: In situ electrochemical gas chromatography

Electric double layer capacitors (EDLCs) are known for their high-power densities due to the fast mechanism of charge-discharge processes. However, producing eco-friendly and economically viable materials for supercapacitors is one of the most important challenges. Also, a high-rate capability of the supercapacitor is desirable for pulse applications. In the present work, a high cell-potential and high-rate supercapacitor was created using biocarbon derived from a rubberwood-sawdust biomass at three different temperature. Bio-AC carbonized at 900 °C shows a high specific surface area of 1932 m2 g−1 and a pore volume of 1.44 cm3 g−1. A symmetrical supercapacitor of bio-AC(900 °C) with 1.0 M LiTFSI(aq.) displays a high practical cell potential of 1.8 V with an impressive rate up to 100 A g−1. A specific capacitance of ∼100 F g−1 at 0.1 A g−1 was estimated by a galvanostatic charge-discharge method. Besides, an excellent capacitance retention is retained at higher specific currents, for instance, 71% and 49% were estimated at 60 A g−1 and 100 A g−1, respectively. An excellent long-term stability of 84% at 1.8 V was evaluated for the symmetrical supercapacitor in 1.0 M LiTFSI(aq.) after 50,000 cycles at 3.0 A g−1. Also, gas chromatography coupled with the electrochemical cell was employed for the in situ determination of electrolytically generated gases in real time at the positive and negative applied potentials. H2 and CO2 gasses can be generated at too high applied potentials. Understanding the gas evolution in this work may be useful for further development of supercapacitors. Also, high cell-potential and high-rate neutral aqueous supercapacitors using activated biocarbon may be useful for high-power applications.

Applying the B12N12 nanoparticle as the CO, CO2, H2O and NH3 sensor

In this study, the various properties including the stability energies, structural and electronic aspects of the hydrazine (N2H4), carbon monoxide (CO) water (H2O) and ammonia (NH3) molecules adsorptions on the top of the boron nitride nanoparticles (BNn) were studied through the Minnesota Functionals computations, DFT/M06-2X. The calculations clarifies that the most stable adsorption configurations are those in which the oxygen, carbon, oxygen and nitrogen atoms of CO2, CO, H2O and NH3 are closed to the boron atom of the nanoparticle, respectively. The absorption energies were obtained about -0.14, -0.15, -0.87 and -1.54 eV for abosorption of CO2, CO, H2O and NH3 gasses. The geometry optimizations, energy calculations and NBO charge transfer were used to evaluate the sensing ability of BNn for different analytes. The computed density of states (DOS) clarifies that a strong orbital hybridization take place between CO2, CO, H2O and NH3 and BNn in adsorption process. Finally, it is concluded that the BNn nanoparticle has greater response selectivity toward NH3 compared to CO, CO2 and H2O

Functionalized and engineered nanochannels for gas separation

Abstract In this work, we present the hydrogen selective gas separation properties of the track-etched poly (ethylene terephthalate) (PET) membranes, which were functionalized with a carboxylic group. Also, Palladium (Pd) nanoparticles of average diameter 5 nm were deposited for a various time on pore walls as well as on the surface of carboxylated membranes. Effect of Pd nanoparticles binding with the increase of deposition time on gas separation and selectivity was studied. For the study of surface morphology of these composite membranes and the confirmation of Pd nanoparticles binding on the surface as well as on pore walls is characterized by scanning electron microscopy (SEM). The gas permeability of carboxylated membrane with increasing Pd deposition timing for hydrogen (H2), carbon dioxide (CO2) and nitrogen (N2) was examined. From the gas permeability data of H2, CO2 and N2 gasses, it was observed that these membranes have higher permeability for H2 as compared with CO2 and N2. Selectivity of H2/CO2 and H2/N2 improves with the increased Pd nanoparticles deposition time. These membranes have effective application in the field of hydrogen based fuel cell.

Study on the evaluation system of urban low carbon communities in Guangdong province

In recent years, China has been gradually consolidating the establishment of Low Carbon Communities (LCC) to minimize the emission of CO2 and other greenhouse gasses. Guangdong Province, as one of the low-carbon pilot provinces, has also paid great attention to the building of LCC. However, currently Guangdong province, or even China as a whole, has no official evaluation system in place which can be employed to evaluate the degree of low carbon of urban LCC. This paper aimed to establish a system for evaluating the urban LCC of Guangdong Province based on their actual situations. The system divided the evaluation into six categories, applied the SMART criteria to select suitable indices, and set the reference values for two zones, i.e., the Pearl River Delta zone (PRD) and the non-PRD zone. Monte Carlo and AHP were combined for the calculation of index weights, thus ensuring that the weight judgment matrixes could all pass the consistency check. In addition, this paper also laid down detailed evaluation regulations to improve the operability of this system and guarantee its wide application and better generalization. Finally, one typical urban community was selected to test the operability of this system, and the One-At-a-Time (OAT) method was used to analyze the sensitivity of each index and explore the degree of influence of these indices on evaluation results. The results showed that three indicators corresponding to green building percentage, new energy vehicles percentage and low carbon public transportation had the highest sensitivity. After field test evaluation, the evaluation system was found to have strong operability, and a high accessibility to indicator data. This system cannot only be used as a tool by the Provincial People's Government of Guangdong to evaluate the construction progress and degree of low carbon in LCC, but can also provide a reference point and experience for the Chinese government to draw upon in establishing the evaluation system of LCC at a national level.

(Invited) CO2 Photoreduction By Cux０ Nanocluster Loaded SrTiO3 Nanorod Thin Film

Introduction Photocatalytic carbon dioxide reduction, in which CO2 is converted into organic compounds, such as methane, methanol, formic acid, and formaldehyde, has the potential to greatly contribute to reducing global warming and fossil fuel dependence. In artificial photosynthesis systems designed for the reduction of CO2 for solar fuel production, water molecules should ideally serve as the electron donor, similar to photosystems I and II in natural plants. Recently, our group reported that a copper oxide nanocluster cocatalyst drives the multi-electron reduction of both oxygen and CO2, i. e. the production of hydrogen peroxide from oxygen and carbon monoxide (CO) production from CO2.1 Our copper oxide consists of Cu(I) and Cu(II) valence states during the CO2 reduction reaction, and it is designated as CuxO (x=1 or 2). Copper compounds have balanced chemisorption-desorption properties for CO2 and CO, and therefore have high CO2 reduction activity and high selectivity of products, such as CO and formic acid. Herein, we examined the potential of strontium titanate (SrTiO3: STO) to function as a light harvester with loading of CuxO cocatalysts, as the STO has high chemical stability and sufficient negative conduction band for CO2 reduction. In the present research, we used STO nanorod thin films as a UV-light harvester due to its higher crystallinity and increased surface area for the loading of CuxO cocatalyst. The photocatalytic CO2 reduction activity of CuxO cocatalyst loaded STO nanorod (CuxO-STO) thin films was evaluated under UV-light irradiation in the present study. Experimental STO nanorod thin films were synthesized by the annealing of strontium ion-exchanged titanate nanotube thin films. Titanate nanotube thin film was prepared by the hydrothermal treatment of titanium (Ti) foil (2×2×0.1 cm3, Nilaco Co.).2 CuxO nanocluster cocatalyst was loaded onto the STO nanorod thin film using an impregnation method.3 The sample morphologies were observed by SEM and TEM. Chemical compositions of the sample were investigated using an EDX equipped with a TEM apparatus. The valence number of copper nanoclusters was determined by measuring ESR. The prepared CuxO-STO film was immersed into an electrolyte solution in a sealed quartz glass reactor. To purge air in the reactor, CO2 or Ar gasses were bubbled into the reactor through a Teflon tube. Products in the headspace of the reactor were evaluated using a gas chromatograph (FID) equipped with a methanizer unit under UV light irradiation. Results and discussion The TEM image analysis revealed that amorphous nanoclusters of 2-3 nm in size were attached and highly dispersed on the STO nanorods. In the obtained EDX spectrum, a signal corresponding to Cu was clearly observed. ESR spectrum of bare STO nanorod thin film did not showed any obvious peaks corresponding to copper ions or any changes to the spectrum after UV irradiation. In contrast, the CuxO-STO film exhibited a broad ESR peak, which was assigned to Cu2+ species, around 345 mT under dark conditions, and this peak decreased in intensity after UV irradiation. Thus, under UV-light irradiation, photo-excited electrons of STO were injected into the CuxO nanocluster cocatalyst. The time course of photocatalytic CO generation for bare STO and CuxO-STO film under UV irradiation with Ar or CO2 bubbling conditions were measured. The amount of CuxO in the film was optimized to be 0.0005 wt%. The loading of the CuxO-cocatalysts onto STO nanorods clearly improved the photocatalytic CO2 reduction activity compared to bare STO nanorods. We also conducted isotope tracer analysis on the optimized CuxO-STO film. The peaks in the mass chromatography spectra at m/z = 29 and 36 were assigned to 13CO and 18O2, respectively. These results confirmed that the CO generated by the CuxO-STO film originated from CO2, and that O2 molecules were produced through water oxidation. Conclusion We have demonstrated the applicability of modifying SrTiO3 with CuxO nanoclusters as a cocatalyst for CO2 photoreduction. The CuxO-STO film exhibited high activity and selectivity for CO evolution under UV irradiation. The isotope tracer analysis confirmed that water served as an electron donor and that CO molecules were produced by the reduction of CO2 under UV irradiation. As the CuxO-STO material is composed of non-toxic and abundant elements, it has the potential to be an efficient photocatalyst for CO2 reduction.

Low-cost, high-performance nonevaporable getter pumps using nonevaporable getter pills

Nonevaporable getter (NEG) pumps are widely used for maintaining a clean ultrahigh vacuum (UHV) of ≤10−8 Pa because of their high pumping speeds for hydrogen (H2) and active gases in the UHV region. In addition, they are oil free, evaporation free, sputtering free, sublimation free, magnetic field free, vibration free, economical, compact, lightweight, and energy saving. In the present paper, the authors report a new NEG pump which is composed of commercial 60 NEG pills (ϕ10 × 3 mm; 70 wt. % Zr, 24.6 wt. % V, and 5.4 wt. % Fe), titanium parts, a DN 40 conflat flange, and a tantalum heater. The NEG pills are vertically and radially aligned around the heater to maximize the effective area for pumping. After activation at 400 °C for 30 min, the pumping speeds of the NEG pump were measured with the orifice method. Pumping speeds of 140–130, 200–140, 190–130, and 35–17 l/s were estimated for H2, CO, CO2, and N2 gasses, respectively, in a pumped-quantity range of 0.01–0.1 Pa l. Since the NEG pump is composed of a heating unit and a NEG module, the pumping speeds can be improved by increasing the number of NEG modules. These NEG pumps are favorable alternatives to sputtering ion pumps or titanium sublimation pumps.

An investigation in 20 kWth oxygen-enriched bubbling fluidized bed combustor using coal and biomass

The current article presents the experimental finding of co-firing coal with biomass under air-fired and oxygen-enriched conditions in a 20kW bubbling fluidized bed (BFB). For the same, rice husk (RH), Prosopis juliflora (PJ), pine needles (PN) and plant litter (PL) are used as biomass alongside the coal. The bounteous accessibility of biomass in Northern region of India is the primary explanations behind its choice. The best possible usage of these biomass can possibly fortify the economy and additionally decreases the pollution. The experimental results show that the coal-biomass blend burns successfully inside the combustor, and the maximum temperature observed in the splash zone. A maximum conceivable combustion efficiency of 97.09% is accomplished with 75%coal/25%PJ under oxygen-enriched condition. The measured percentage of NOx, CO2 and other gasses is highly influenced by oxygen intake. The energy consumption, exergy destruction, and exergy efficiency are also assessed for fuels used. Exergy efficiency is varying from 30% to 58% for all the cases. The effect of particle size distribution on combustion efficiency is additionally studied. Among the four biomass fuels tested, PJ and PN have the best execution in co-firing mode.

An efficient energy‐aware predictive clustering approach for vehicular ad hoc networks

SummaryWith an emergence of information and communication technologies, there is an increase in the demands of providing safety and comfort to the passengers during their mobility on the road. These demands can be fulfilled by one of the most popular networks of its type—vehicular adhoc networks (VANETs). As vehicles in VANETs are constrained with respect to the available resources such as computation and storage, lot of energy is consumed to perform a number of complex operations, which may lead to the emission of harmful CO2 emission that effect the global warming system. Moreover, because of high velocity led by constant topological changes, it is a challenging task to maintain quality of service with respect to parameters such as high throughput, and minimum end‐to‐end delay. Hence, an intelligent approach is required to optimize the various complex operations in this environment, which may led to the minimum emission of CO2 and other gasses. To address these issues, this paper proposes an efficient energy‐aware predictive clustering scheme for vehicles. Efficient algorithms are designed for future mobility predictions and average variations of vehicles on the road. The algorithms estimate the clustering duration and total vehicles in the cluster. The performance of the designed algorithms is studied using extensive simulations by varying the number of vehicles and cluster durations in comparison with existing benchmarked scheme in the literature. The results obtained show that the proposed scheme is superior in comparison with the existing scheme of its category. Copyright © 2015 John Wiley & Sons, Ltd.

Fabrication and structural properties of porous Cu–YSZ cermets for solid oxide fuel cells

In this study, porous Cu–YSZ cermets with various Cu contents are fabricated and their crystal structure and morphological features are investigated by X-ray diffraction and scanning electron microscopy. Carbon black-containing CuO/Y2O3-stabilized ZrO2 (YSZ) composites exhibit a highly porous structure due to the evolution of CO and CO2 gasses during sintering. The porosity of the CuO/YSZ composites decreases with increases of the sintering temperature and CuO content. Highly porous Cu/YSZ cermets are fabricated by reducing the porous CuO/YSZ composites in (Ar+6% H2) atmosphere. Higher CuO content and higher sintering temperature reduce the porosity of Cu/YSZ cermets after reduction treatment. The microstructure and porosity of Cu/YSZ cermets as an anode material are remarkably affected by the CuO content, sintering temperature, and carbon black content. We believe that the porous Cu/YSZ cermets are a promising anode material for high performance of SOFC.

Influence of silica addition on the properties of epoxidised natural rubber/polyvinyl chloride composite membrane

AbstractFlexible and porous epoxidised natural rubber (ENR)/polyvinyl chloride (PVC) membranes were prepared via phase inversion technique. The pore formation on ENR/PVC membranes was initiated with the introduction of inorganic particles (silica). Two types of silica, microsilica (microcrystalline silica powder) and nanosilica [generated from Tetraethoxysilane (TEOS)] were used. Effects of silica addition on the membrane structure are investigated by means of FTIR, SEM, TGA, and UTM. FTIR results showed the presence of signature peak of SiOSi at 1102 and 1088 cm−1 for ENR/PVC/SiO2 and ENR/PVC/TEOS membrane, respectively. Morphological studies showed that pores developed in ENR/PVC/TEOS membranes were more homogenous as compared to ENR/PVC/SiO2 membranes. Thermal and mechanical stability of the membranes improved with the incorporation of silica. ENR/PVC/SiO2 membrane exhibited better mechanical and thermal properties as compared to ENR/PVC/TEOS membranes. CO2 and N2 gas permeation of silica‐filled membranes increased with increasing silica content and the permeability of ENR/PVC/SiO2 membrane toward N2 and CO2 gasses was higher than ENR/PVC/TEOS membrane. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Effects of digestate from anaerobically digested cattle slurry and plant materials on soil microbial community and emission of CO2 and N2O

Anaerobic digestion of animal manure and crop residues may be employed to produce biogas as a climate-neutral source of energy and to recycle plant nutrients as fertilizers. However, especially organic farmers are concerned that fertilizing with the digestates may impact the soil microbiota and fertility because they contain more mineral nitrogen (N) and less organic carbon (C) than the non-digested input materials (e.g. raw animal slurry or fresh plant residues). Hence, an incubation study was performed where (1) water, (2) raw cattle slurry, (3) anaerobically digested cattle slurry/maize, (4) anaerobically digested cattle slurry/grass-clover, or (5) fresh grass-clover was applied to soil at arable realistic rates. Experimental unites were sequentially sampled destructively after 1, 3 and 9 days of incubation and the soil assayed for content of mineral N, available organic C, emission of CO2 and N2O, microbial phospholipid fatty acids (biomass and community composition) and catabolic response profiling (functional diversity). Fertilizing with the anaerobically digested materials increased the soil concentration of NO3− ca. 30–40% compared to when raw cattle slurry was applied. Grass-clover contributed with four times more readily degradable organic C than the other materials, causing an increased microbial biomass which depleted the soil for mineral N and probably also O2. Consequently, grass-clover also caused a ∼10 times increase in emissions of CO2 and N2O greenhouse gasses compared to any of the other treatments during the 9 days. Regarding microbial community composition, grass-clover induced the largest changes in microbial diversity measures compared to the controls, where raw cattle slurry and the two anaerobically digested materials (cattle slurry/maize, cattle slurry/grass-clover) only induced minor and transient changes.

Feasibility Study of 1 MW Standalone Hybrid Energy System: For Technical Institutes

Hybrid energy system (HES) is a combination of different renewable resources such as wind, solar, biomass, small/micro hydro, with fossil fuel powered diesel generator to provide electric power. This paper gives the design idea of optimized Hybrid Energy System for a certain technical college over a conventional diesel generator for a particular site in eastern India (Kolkata). For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Kolkata-Eastern India (Longitude 88°22’and Latitude 22°34’) and the pattern of load consumption of technical college are studied and suitably modelled for optimization of the hybrid energy system using HOMER software. This paper gives the detail hypothetical study for standalone hybrid energy system for technical institute in five stages: (a) recent electric bill of the college for the year 2011. (b) Studying the load demand for every month in a year. (c) Calculating the maximum, minimum and the average load demand. (d) Introducing the solar data in HOMER software. (e) Designing the hybrid model. This system is more cost effective and environmental friendly over the conventional diesel generator. It should reduced approximate 70% - 80% fuel cost over conventional diesel generator and also reduced the emission of CO2 and other harmful gasses in environments. The action plan is formed on the basis of cost effective modelling that is minimization of energy production cost in a long run.

SPECIAL—Savanna Patterns of Energy and Carbon Integrated across the Landscape

Savannas are highly significant global ecosystems that consist of a mix of trees and grasses and that are highly spatially varied in their physical structure, species composition, and physiological function (i.e., leaf area and function, stem density, albedo, and roughness). Variability in ecosystem characteristics alters biophysical and biogeochemical processes that can affect regional to global circulation patterns, which are not well characterized by land surface models. We initiated a multidisciplinary field campaign called Savanna Patterns of Energy and Carbon Integrated across the Landscape (SPECIAL) during the dry season in Australian savannas to understand the spatial patterns and processes of land surface–atmosphere exchanges (radiation, heat, moisture, CO2, and other trace gasses). We utilized a combination of multiscale measurements including fixed flux towers, aircraft-based flux transects, aircraft boundary layer budgets, and satellite remote sensing to quantify the spatial variability across a continental-scale rainfall gradient (transect). We found that the structure of vegetation changed along the transect in response to declining average rainfall. Tree basal area decreased from 9.6 m2 ha−1 in the coastal woodland savanna (annual rainfall 1,714 mm yr−1) to 0 m2 ha−1 at the grassland site (annual rainfall 535 mm yr−1), with dry-season green leaf area index (LAI) ranging from 1.04 to 0, respectively. Leaf-level measurements showed that photosynthetic properties were similar along the transect. Flux tower measurements showed that latent heat fluxes (LEs) decreased from north to south with resultant changes in the Bowen ratios (H/LE) from a minimum of 1.7 to a maximum of 15.8, respectively. Gross primary productivity, net carbon dioxide exchange, and LE showed similar declines along the transect and were well correlated with canopy LAI, and fluxes were more closely coupled to structure than floristic change.