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In order to explore a harmless and resource-based way to treat municipal solid waste (MSW) and paper sludge (PS), the co-pyrolysis MSW and PS was studied in this paper. Firstly, MSW and PS had the lower residue mass, and MSW had higher pyrolysis index under CO2 atmosphere, compared with the one under N2 atmosphere. Hence, the CO2 was used as the carrier gas in the following study. Secondly, under CO2 atmosphere, the co-pyrolysis of MSW and PS with and without MgO were researched. With the increasing of PS ratio, the pyrolysis performance of the blends decreased constantly. MgO act as catalyst could improve the pyrolysis characteristic index of the blends. However, MgO was an inorganic salt and it would affect the synergistic effect of MSW and PS. The curves of online evolutions of all the gas products and the functional groups had an obvious peak at around 500 ℃. The activation energy of the blends in the first step (

International audience; The global warming of Earth's near-surface, air and oceans in recent decades is a direct consequence of anthropogenic emission of greenhouse gases into the atmosphere such as CO2, CH4, N2O and CFCs. The CO2 emissions contribute approximately 60% to this climate change. This study investigates experimentally the aqueous carbonation mechanisms of an alkaline paper mill waste containing about 55 wt% portlandite (Ca(OH)2) as a possible mineralogical CO2 sequestration process. The overall carbonation reaction includes the following steps: (1) Ca release from portlandite dissolution, (2) CO2 dissolution in water and (3) CaCO3 precipitation. This CO2 sequestration mechanism was supported by geochemical modelling of final solutions using PHREEQC software, and observations by scanning electron microscope and X-ray diffraction of final reaction products. According to the experimental protocol, the system proposed would favour the total capture of approx. 218 kg of CO2 into stable calcite/ton of paper waste, independently of initial CO2 pressure. The final product from the carbonation process is a calcite (ca. 100 wt%)-water dispersion. Indeed, the total captured CO2 mineralized as calcite could be stored in degraded soils or even used for diverse industrial applications. This result demonstrates the possibility of using the alkaline liquid–solid waste for CO2 mitigation and reduction of greenhouse effect gases into the atmosphere.

A 1-year study of bulk atmospheric dissolved inorganic nitrogen (DIN) deposits has identified a medium anthropogenic impact in the southwest of France (average NO3 concentration=26.2 μM; yearly NO3 flux=22.6±5 mmol/m2 per year; average NH4 concentration=17.8 μM; yearly NH4 flux=14.6±3 mmol/m2 per year). The air flow directions have shown that the contamination is derived from Spain and the south of France during the winter period and from northern Europe in the summer period. However, long range transport of ammonia is less probable because of its short residence time in the atmosphere due to its high solubility. Moreover, a seasonal variation has affected ammonium (2.4 times higher in the cultivation period), while nitrate remained statistically constant. Although no difference of ammonium concentration was observed under the influence of oceanic and continental winds, it must be influenced by regional emissions from agricultural areas. In the summer period, the atmospheric source makes up 26% of the total DIN inputs into the Arcachon Lagoon. Moreover, an exceptional storm event represented 96% of the total input in a single day. Thus, such a seasonal pattern suggests an important impact of atmospheric DIN deposits on primary production in coastal ecosystems of such a region less industrialized since they often show oligotrophic conditions in the summer period.

The paper under discussion suggests either that the CO mixing ratio diminishes strongly with increasing height over several large volcanoes, but not in the free atmosphere, or that an absorbing mineral is present on the surface with coverage correlated with height. This note proposes as a third possibility a tiny instrumental error, possibly the presence of very faint wings to the instrumental profile which could be due to scattered light. Raising the continuum level by about 0.3% in the low-resolution spectra will give a more reasonable result of a height-independent mixing ratio.

In the title paper by W. B. Hubbard, the author presents the third of his three fundamentally different published solutions for the same problem. We conclude that it too is incorrect, that his accompanying discussion contains several basic inconsistencies, and that even if his results were corrected, they would not apply to the actual experiments in the manner he proposes.

Simple one and two layer models of the atmosphere are used to derive properties of the downwind position and value of the maximum in mean ground level concentration which can effect either the handling or the interpretation of field data. It is shown that this maximum is quite flat, implying that whilst the peak value can be found accurately its position will be subject to large errors. The effect of stable layers above the source is also discussed and it is indicated how much of the scatter in field results can be attributed to this cause. The distribution of maximum concentration values which arise from a simple distribution of stable layer heights is evaluated and compared with experiment.

Wood pellets are a commonly used biomass for energy production. However, due to the growing demand, many entrepreneurs have begun to produce non-wood biomass pellets. During experimental research, the process of combusting pellets of forest and agricultural origin at different furnace temperatures and different oxidizing atmospheres in a two-phase flow with the use of inert material modelling conditions in the upper zone of the fluidized bed reactor was analyzed. Inert material caused very significant differences in the time and mechanism of forest and agro biomass combustion. These differences are mainly associated with problematic phenomena during combustion, including sintering of ashes. The inert material accelerated the mass loss of forest biomass pellets at all temperatures by about 50–60%. In the case of agro biomass, the combustion time at the temperatures of 650 °C and 750 °C was shortened by about 20–30%, and in the case of the temperature of 850 °C, it was extended by about 10%. Increasing the value of the inert material stream resulted in a reduction of the combustion time at all temperatures. Increasing the concentration of oxidant in the atmosphere of combustion caused the reduction of the combustion time of all tested fuels.

The aim of the present work is to provide a preliminary support and research foundation for developing integrated technology of methane dry reforming and pine wood pyrolysis to produce high value chemicals and fuels. The chemical properties of bio-oil produced by pine wood pyrolysis under traditional N2, H2, CO2, CH4 atmospheres and mixtures of CH4 and CO2 were investigated. Experimental studies were conducted in a fixed bed reactor at a temperature of 500 °C. The results show that pine wood pyrolysis under mixtures of methane and CO2 can promote bio-oil production (0.98% increase) compared with traditional pyrolysis (under N2). GC-MS results show that the contents of phenols and sugars in bio-oil decreased, while the amount of alcohols, aldehydes, ketones, and furans increased. NMR spectroscopy provides additional support of the results. Results indicate that bio-oil can be used as a source of value-added chemicals. High proportions of CO were obtained in the gas products from pine wood pyrolysis under CH4 and mixtures of CH4 and CO2. Finally, a possible reaction pathway of pine wood pyrolysis under mixtures of methane and CO2 is proposed. Methane bi-reforming with CO2 and steam from pine wood pyrolysis could promote the production of high value oxygen-containing chemicals during pine wood pyrolysis under mixtures of CH4 and CO2.

Night-time variations of the OH nightglow intensity reported by Wiens and Weill are compared with the theoretical predictions of a number of models. The behaviour of this emission agrees better with the theoretical one for locations in the equatorial zone but becomes more variable and less predictable for mid-latitude stations. It is calculated that, as a result of an increase of the eddy diffusion coefficient K, the OH emission can deviate from the typical night-time variation and increase by a factor as high as 2 if K is multiplied by 10. It is suggested that the eddy diffusion coefficient in the upper atmosphere is lower and undergoes lower amplitude variations in the equatorial zone than in the mid-latitude regions.

Summary Using a 2,6-lutidine-water (5:1) system in an atmosphere of 0.88 s.g. ammonia, it is possible to separate mesoporphyrins I and IX. Five parts of the former is detectable when admixed with 95 parts of the latter. Since haems and protoporphyrins may be converted to mesoporphyrins without change in isomer type the technique renders possible the detection of this proportion of protoporphyrin I in haem or porphyrincontaining biological materials.

Co-pelletization of sewage sludge (SS) and conventional fuels for combustion is considered to be a feasible SS disposal method. Oxy-fuel combustion is recognized as a promising technology to reduce the emission of CO2. In practical applications, the combustion atmosphere in oxy-fuel boiler is O2/CO2/H2O, which is different from that in the conventional boiler (O2/N2). Therefore, the effects of gas composition on the combustion characteristics of boiler fuels should be both taken into consideration. In this work, the SS/pine sawdust (PS) and SS/bituminous coal (BC) blended fuel particles were prepared, and the single particle combustion experiments were conducted in O2/N2, O2/CO2 and O2/CO2/H2O atmospheres. The influences of SS blending proportion and gas composition on combustion characteristics of fuel particles were analyzed. The results reveal that increasing the blending proportion of SS from 20 to 40 wt% decreases the ignition delay time, burnout time and combustion temperature. The substitution of N2 by CO2 increases the ignition delay time and burnout time, while decreases the combustion temperature. Replacing CO2 by 10 vol%, 20 vol% and 30 vol% H2O decreases the ignition delay time and burnout time, while increases the combustion temperature.

The pyrolysis characteristics of sewage sludge, wheat straw and its mixture were studied by non-isotropic thermogravimetric analysis (TGA). In the temperature range of 400 K–950 K, 40 K/min, 45 K/min and 50 K/min heating rate were set respectively, in N2 atmosphere and CO2/N2 mixed atmosphere. According to the thermal analysis chart obtained from TGA, it was observed the vast majority of mass loss spread at the range of 450–800 K in all samples. The Co-pyrolysis kinetics of sewage sludge and wheat straw was described by a fourth-order DAEM model. It is proved that the model can well match the TG experimental data. The results obtained from the optimized parameters show that the activation of sewage sludge is lower than that of wheat straw, and the activity of the mixture gradually increased with the increase of wheat straw content. The presence of CO2 has a slight inhibitory effect on the pyrolysis of the mixture below 900 K compared to that in an N2 atmosphere, but with temperature increasing, CO2 will have a secondary reaction with biochar.

The efficient production of high calorific value solid fuel from palm oil empty fruit bunch (EFB) was investigated by experimenting hydrothermal carbonization (HTC) with initial absolute pressures of 0.1 MPa, 1.3 MPa, and 3.1 MPa in N2 atmosphere and in CO2 atmosphere. The pressure increase in HTC is expected to promote the improvement of calorific value in efficient way, while the alteration of reaction atmosphere from N2 to CO2 is aimed at obtaining higher extent of carbonization. Increasing the initial pressure of N2 improved calorific value of the derived fuel from 19.3 MJ/kg to 22.2 MJ/kg, while creating only trivial effect on energy yield. Increasing the initial pressure of CO2 further enhanced the carbonization and resulted in fuel with maximum calorific value of 23.6 MJ/kg. However, it also resulted in up to 6% reduction on energy yield compared with the cases with N2. The advantages of pressurized HTC in N2 atmosphere and in CO2 atmosphere over conventional HTC were evident when used for the production of fuels with comparable heating value. Process efficiencies of the pressurized HTC in both N2 and CO2 atmospheres were shown to be 4–8% higher than those of conventional HTC with normal initial reaction pressure.

An experimental study on co-pyrolysis of bituminous coal and biomass was performed in a pressured fluidized bed reactor. The blend ratio of biomass in the mixture was varied between 0 and 100 wt%, and the temperature was over a range of 550–650 °C under 1.0 MPa pressure with different atmospheres. On the basis of the individual pyrolysis behavior of bituminous coal and biomass, the influences of the biomass blending ratio, temperature, pressure and atmosphere on the product distribution were investigated. The results indicated that there existed a synergetic effect in the co-pyrolysis of bituminous coal and biomass in this pressured fluidized bed reactor, especially when the condition of bituminous coal and biomass blend ratio of 70:30 (w/w), 600 °C, and 0.3 MPa was applied. The addition of biomass influenced the tar and char yields and gas and tar composition during co-pyrolysis. The tar yields were higher than the calculated values from individual pyrolysis of each fuel, and consequently the char yields were lower. The experimental results showed that the composition of the gaseous products was not in accordance with those of their individual fuel. The improvement of composition in tar also indicated synergistic effect in the co-pyrolysis.

Straw sample was torrefied at 260 °C and 300 °C in N2, respectively, to prepare torrefied straw named as T-260 and T-300, and the reduction effect of co-firing straw or torrefied straw and steam coal on PM1 is investigated. The combustion experiments were conducted in a high temperature drop tube furnace (DTF) at 1400 °C to collect the inorganic PM10 for further analysis. Combustion atmosphere was air for all cases and 50% O2/50% CO2 (OXY50) for coal, T-260 and their blends of 1:1 and 4:1. The results show that all three biomass fuels show obvious emission reduction of PM with aerodynamic diameters of ≤ 0.3 µm (PM0.3) under both mix ratios. Reduction ratios of co-firing are overall higher at mix ratio of 1:1 than 4:1, and co-firing of T-260 or T-300 with coal shows higher reduction ratio than co-firing of straw. The higher ash content in torrefied straw leads to higher contents of alkali and alkaline earth metals (AAEM), which will further react with both Si and S during co-firing and coagulate into particles of larger sizes, leading to higher reduction ratios of PM0.3 and unconspicuous reduction effects in PM0.3–1 emitted from co-firing. During co-firing in oxyfuel atmosphere, a higher combustion temperature compared to air leads to an intensitive gasification, may resulting in effective and even higher reduction ratio in PM0.3.

Microwave co-pyrolysis (MCP) of waste cooking oil (WCO) and waste polyolefins (WP) was examined for its potential to convert these wastes into liquid fuel. The influence of performing the pyrolysis process under N2 atmosphere and vacuum environment was investigated with emphasis on the temperature profile, heating rate, and the yield and properties of the liquid oil obtained. Different ratios of WP to WCO (1:2, 1:1.5, 1:1, 1.5:1, and 2:1) were also investigated. MCP performed under vacuum environment recorded higher heating rates (20–24 °C/min) and higher yield of liquid oil (up to 62 wt.%) compared to that performed under N2 atmosphere (18–22 °C/min of heating rate and 24–50 wt.% of liquid oil). The high heating rate resulted in shorter reaction time and lower power consumption, leading to lower energy consumption by the pyrolysis process. The liquid oil comprised C13–C24 hydrocarbons (aliphatics, aromatics) within the hydrocarbon range of diesel fuel. It also showed promising green properties comprising low nitrogen and oxygen content, and free of sulphur. Combined with the detection of high energy content (42–49 MJ/kg) and low moisture content (

In this study, batched hydrothermal experiments on corn stalk were conducted at 240–330 °C under CO2 or inert (N2) atmosphere. The distribution and characteristics of gaseous, solid, and liquid products were analyzed in detail to comprehensively investigate the effects of CO2 on the hydrothermal conversion of biomass, especially on the cellulose and lignin in biomass. The results demonstrate that compared with N2, CO2 slightly increased the liquid and gas yields and significantly improved the control effect of temperature on bio-oil components. Under CO2 atmosphere, bio-oil achieved effective enrichment of ketones and phenols at 240 °C and 300 °C, respectively, and their highest relative contents reached 44.8% and 62.0%, respectively. In addition, the hydrochar obtained under CO2 atmosphere showed higher crystallinity, which is conducive to its subsequent utilization. This study explored the feasibility of introducing CO2 into the biomass hydrothermal process to realize the high-value utilization of biomass waste and the reuse of CO2.

In modified atmosphere packaging (MAP), the transpiration of the fresh product and exchange of water through the polymeric packaging are often not properly considered. This paper presents a mathematical model to describe the evolution in water vapour, O2 and CO2 concentrations in the packaging headspace, the weight loss of the product and the condensation of water in a MAP system with perforations. Transpiration was considered as the sum of water transferred out from the product due to the gain of energy from its respiration process and the difference in water activities between the product and the surrounding atmosphere. Respiration was represented using Michaelis–Menten enzyme kinetics. The gas transfer through the packaging and the perforations was described with Fick equations. The temperature influence on these processes was considered to follow the Arrhenius' law. To experimentally determine the model parameters, feijoa fruits (Acca sellowiana Berg) were stored under different storage conditions: packaging type, relative humidity and temperature. The completed model was subsequently validated in a MAP test by packaging fruits in perforated polypropylene (PP) and polylactic acid (PLA) bags for 13 days at 12 °C and 75% RH. Inside the PP bags, a saturated atmosphere (100% RH) was reached and 1.48% of the initial weight in the packed fruit was lost by day 13, while in the PLA bags, an equilibrium RH of 83% and a fruit weight loss of 3.29% were measured. The prediction capacity of the model was satisfactory, with coefficients of determination (R2) between 0.88 and 0.99 for the different tests.

8 figures, 1 table. © 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0, Biomass gasification offers a significant potential to close the loop of agriculture and many other activities that produce biomass residues. Pig manure, a residue produced in farms, has a huge pollutant potential due to its high production and chemical characteristics. It is necessary to take some control measures to decrease it, being pig manure gasification an interesting option. The present work studies the impact of the gasification temperature and atmosphere on the syngas composition (CO, H2, CH4 and CO2) and formation of soot and char in the gasification of pig manure in a drop tube furnace. The temperature varied between 900 and 1200 °C, and the gasification atmospheres included mixtures of O2/N2, O2/CO2/N2 and O2/H2O/N2. The results revealed that i) the syngas H2/CO ratio and its low heating value increase as the gasification temperature increases regardless of the gasification atmosphere; ii) the addition of H2O to the O2/N2 gasification atmosphere augments significantly the syngas H2/CO ratio, but does not enhance its low heating value, while the addition of CO2 increases slightly the H2/CO ratio, but significantly the heating value, iii) for the present reactor, the optimum operating conditions for the gasification of the pig manure in terms of syngas heating value and yield are a gasification temperature of 1200 °C and a gasification atmosphere composed of a mixture of O2/CO2/N2; and iv) soot yields increase as the temperature increases when gasification occurs in the O2/N2 and O2/CO2/N2 environments, remaining almost constant in the O2/H2O/N2 environment., This work was supported by the Fundação para a Ciência e a Tecnologia, through IDMEC, under LAETA, project UID/EMS/50022/2019. I. Adánez-Rubio acknowledges the MINECO and University of Zaragoza for the post-doctoral contract awarded (FJCI-2015-23862) and the contract, the Ibercaja and CAI (Ibercaja-CAI Europa program) foundations and COST Action CM1404 (European Union) for financial support (Refs. ECOST‐STSM‐CM1404‐42605 and COST‐STSM‐CM1404‐43695).

Corncob was torrefied under nitrogen and carbon dioxide atmospheres at 220-300 °C, obtaining solid products with mass yields of 69.38-95.03% and 67.20-94.99% and higher heating values of 16.58-24.77 MJ/kg and 16.68-24.10 MJ/kg, respectively. The changes of physicochemical properties of the charcoal was evaluated by many spectroscopies, contact angle determination, and combustion test. Hemicelluloses were not detected for the torrefaction under the hard conditions. As the severity increased, C concentration raised while H and O concentrations reduced. Combustion test showed that the burnout temperature of charcoal declined with the elevation of reaction temperature, and torrefaction at a high temperature shortened the time for the whole combustion process. Base on the data, torrefaction at 260 °C under carbon dioxide was recommended for the torrefaction of corncob.

Textile dyeing sludge (TDS) is a highly toxic solid waste whose co-pyrolysis can jointly achieve waste reduction and recovery of value-added products. This study aimed to fill the knowledge gaps about the co-pyrolysis mechanisms and products (gases and solids) and their dynamics in response to the atmosphere type, blend ratio, heating rate, temperature, and their interactions. The high temperature pyrolysis (>720 °C) in the CO2 atmosphere appeared as the best option for the waste reduction. The (co-)pyrolysis in the CO2 atmosphere enhanced S-containing air pollutants, CO, and CH4 but reduced NOx. The interaction effect between TDS and durian shell (DS) residues promoted the productions of furan and acid compounds and inhibited the productions of aromatic, phenolic, and N-containing compounds. The atmosphere type affected the type and strength of the reactions involved in the production of biochars. Our findings provide practical and new insights into the optimization of energy generation, product recovery, and emission control during the (co-)pyrolysis.

During the operation of industrial gasifier, the concentrations of CO2 and H2O in gasification media vary with the change of stages, causing the gasification process being affected accordingly. Therefore, dividing the gasification process into different stages to study the effect of multi-stage switching atmosphere is significant. The conversion rate, reaction characteristics and reaction process for the gasification of Xiaolongtan (XLT) coal char in different atmospheres (CO2/H2O/N2) switching in the early, middle and late reaction stages were investigated using thermo-gravimetric analysis (TGA). The results indicated that the average reaction rate of coal char with H2O was approximately 3 times that of CO2. Increasing H2O concentration improved the reaction and conversion rate of coal char, which was the most obvious in the early stage. With the H2O concentration increasing from 0 to 95%, the increment of conversion rate in the early, middle, and late stages were 7.13%, 4.40%, and 3.92%, respectively. Thus, considering the problem of H2O corrosion in practical production, the H2O concentration could be appropriately increased in the early stage to improve efficiency. Compared with the random pore model, the shrinking core model fitted the gasification process of coal char better in a highly reactive 95% H2O/5% N2 atmosphere.

This work seeks the integral use of all major components of Hesperaloe funifera , separating hemicelluose by hydrothermal treatments; cellulose by pulping processes; and exploitation of lignin of pulping liquor by pyrolysis and gasification processes. By using sulfuric acid in the hydrothermal treatment (150–190 °C, 0–20 min after reaching operating temperature, 6–10 liquid/solid ratio, 0.1–0.5% sulfuric acid), the glucose and xylose of liquid fraction increase from 1.5% to 5.9%, and 4.0% to 12.4%, respectively; the yields of solid fraction decrease from 91.6% to 79.5%, and the lignin content increase from 23% to 32%. Pulps and paper sheets obtained from solid fractions hydrothermal treatments and from raw material pulped with diethanolamine, are worse than those obtained with soda–anthraquinone (Yield 57.8%; kappa number 24.9; Viscosity 711 mL/g; Brightness 54.8%; Tensile index 73.6 Nm/g; Stretch 2.84%; Burst index 6.13 kN/g and Tear index 1.69 mNm 2 /g). By acidification (pH 6) of soda pulping liquor it separate lignin-rich solids, which by pyrolysis gave a gas containing 1.13% H 2 , 31.79% CO and 1.86% CH 4 by weight. Gasification of the same sample provided a gas containing 0.18% H 2 , 24.50% CO and 17.75% CH 4 .

The oil palm trunk chips were dried in a laboratory scale convective drying at two different operating conditions; open air fan drying and control atmosphere drying (25 °C and 80% relative humidity). The experimental drying data were used to estimate the drying kinetics and to select the suitable form of drying curves. Six different mathematical models such as Henderson–Pabis, Logarithmic, Midilli–Kucuk, Newton, Page, Wang–Singh models and the newly introduced modified Midilli–Kucuk model were applied to the experimental data and their co-efficient of regression, root mean square errors and sum of square error, were compared and predicted by non-linear regression analysis using the MATLAB R2011b (7.13.0.564) software. It was found that the proposed modified Midilli–Kucuk model could predict the drying rate curve when compared with the experimental data point for the drying of oil palm trunk chips.

This study investigated producing biochar from Geodae-Uksae 1 for soil applications to sequestrate carbon from the atmosphere and improve the productivity of crops. Using a lab-scale packed bed reactor, pyrolysis products of Geodae-Uksae 1 were produced over a temperature range of 300-700°C with a heating rate of 10°C/min. Pyrolysis at 500°C was found appropriate for biochar production considering the properties of char and the amount of heat required. It yielded biochar of 27.2wt.% that contained approximately 48% carbon in the raw biomass. The surface area of the biochar rapidly increased to 181m(2)/g. Large cylindrical pores with diameters of 5-40μm developed within the biochar due to the vascular cell structure of the parent biomass. The byproducts (bio-oil and gases) were also analyzed for use as fuel.

The combustion characteristics of Malaysia oil palm biomass (palm kernel shell (PKS), palm mesocarp fibre (PMF) and empty fruit bunches (EFB)), sub-bituminous coal (Mukah Balingian) and coal/biomass blends via thermogravimetric analysis (TGA) were investigated. Six weight ratios of coal/biomass blends were prepared and oxidised under dynamic conditions from temperature 25 to 1100 °C at four heating rates. The thermogravimetric analysis demonstrated that the EFB and PKS evolved additional peak besides drying, devolatilisation and char oxidation steps during combustion. Ignition and burn out temperatures of blends were improved in comparison to coal. No interactions were observed between the coal and biomass during combustion. The apparent activation energy during this process was evaluated using iso-conversional model free kinetics which resulted in highest activation energy during combustion of PKS followed by PMF, EFB and MB coal. Blending oil palm biomass with coal reduces the apparent activation energy value.

The influences of storage temperature and modified O 2 and CO 2 concentrations in the atmosphere on the post-cutting life and quality of fresh-cut pineapple ( Ananas comosus ) were studied. Temperature was the main factor affecting post-cutting life, which ranged from 4 days at 10 °C to over 14 days at 2.2 and 0 °C. The end of post-cutting life was signaled by a sharp increase in CO 2 production followed by an increase in ethylene production. The main effect of reduced (8 kPa or lower) O 2 levels was better retention of the yellow color of the pulp pieces, as reflected in higher final chroma values, whereas elevated (10 kPa) CO 2 levels led to a reduction in browning (higher L values). Modified atmosphere packaging allowed conservation of pulp pieces for over 2 weeks at 5 °C or lower without undesirable changes in quality parameters.

Product distribution from straw and washed straw pyrolysis shows the usual temperature (660–990 K) dependence, but the pretreatment makes the initial degradation temperature slightly higher and gives rise to larger yields of condensable products (mainly at the expenses of char). Water washing also affects decomposition of straw in air. Devolatilization again takes place at higher temperatures and with a higher peak rate, but char combustion reactivities are always lower. Hot water washing of large (0.5–1 mm) straw char particles is less effective for ash removal than straw washing, independently of the temperature and the atmosphere where chars were formed. In particular, for low temperature (520 K) and air, the ash removed decreases as successively higher conversion levels are examined.

The effects of controlled atmospheres (CA) of six different compositions, on the keeping quality of stored ‘Hass’ avocado fruit were studied. Atmospheres containing 1, 3 and 8% carbon dioxide in combination with 21% oxygen and atmospheres containing 0.5, 3 and 8% carbon dioxide in combination with 3% oxygen were tested. Storage temperature was 5°C and shelf-life (ripening) temperature was 20°C for all treatments. Results show that elevated carbon dioxide and reduced oxygen concentrations in the atmosphere retarded ripening (softening and peel colour changes), and reduced the development of chilling injuries during storage at 5°C. The 8% carbon dioxide concentration was more effective than 3%, in combination with either oxygen concentration. An atmosphere containing 3% oxygen and 8% carbon dioxide was the best with respect to the parameters mentioned above, and made 9 weeks of avocado storage possible. These results indicate that the two gases have a synergistic effect on inhibiting ripening processes. Following CA storage, fruits softened normally and the peel went through the usual, typical colour changes. However, these two ripening processes were not always in step, suggesting that CA may have a differential effect on ripening of avocado peel and pulp.

To define the rate of 129I transfer from aquatic to terrestrial ecosystems, in support of the Canadian Nuclear Fuel Waste Management Program, we measured rates of 125I and 14C loss from glass flasks. Measured 125I loss rates were less than 0.5% of the 14C loss rate, and water-air partition coefficients for 125I were 7.2 × 104 litre air litre−1 water or greater. Gaseous loss of 125I was slower from river water than from distilled water, and still slower in the presence of algae, or from sediment slurries under oxic or low-oxic conditions. No 125I loss was detectable under methanogenic conditions. Sediment slurries in contact with 125I were used to measure water-sediment partition coefficients (KD) under oxic (KD = 70–187 litre kg−1) and low-oxic (KD = 25–42 litre kg−1) conditions. From this study we conclude that the first-order gaseous evasion rate from fresh water to the atmosphere for 129I is < 1.9 × 10−3 a−1, and that the water-to-sediment transfer rate is between 1.0 and 3.4 a−1.

The size distribution and chemical composition of atmospheric nitrate particles have been investigated. A variety of size distributions of nitrate was measured in Nagoya, Japan. Air samples were collected and size-fractionated in cascade impactors. Size-classified particles were extracted with water and alcohol. The concentrations of nitrate were measured by specific ion electrode and absorption spectrophotometry. The chemical composition of nitrate was identified by paper chromatography. The size distributions of nitrate were bimodal. One modal dia. was ca . 0.4–0.6 μm, the other ca . 3–5 μn. The shapes of the size distribution curves changed periodically with the season. From the analysis by paper chromatography, it was shown that the submicron nitrate was NH 4 NO 3 and the coarse nitrate was NaNO 3 . A strong relationship between size distributions of nitrate and meteorological conditions was found. The mechanisms of nitrate formation in the atmosphere are also discussed.

The disinfestation of cereal grains by means of inert atmospheres is the simplest and least costly physical method to be used as an alternative to chemical treatments in temperate and hot climate zones. For the purpose of replacing the interstitial atmosphere of gas-tight storage bins, nitrogen is particularly suitable, as it is biologically inert and easily available on the market both in gaseous and liquid form. It can be utilized for short fumigations (approx. 20 days) and for the protracted storage of dry (years) and of medium to high moisture content cereals (months), since in the presence of low residual concentrations of oxygen (< 0.3%) the proliferation of moulds is significantly retarded. This paper describes some of the storage experiments carried out with cereals in technical (O2 ≤0.5%) and pure nitrogen. The results of soft wheat at low (< 14.5%), medium (16%) and high (17–18%) moisture content as well as of hard wheat preservation, attest the safety of the method and point out its advantages as compared with storage in air. The economics of the storage technique in nitrogen are advantageous, the operating costs being significantly lower than those of traditional storage methods, based on chemical insecticidal treatments or refrigeration.

A sensitive method is described for the dctermination of parathion in air The air sample is drawn through filter paper or cellulose powder, winch traps both particles and vapour, and the parathion is reduced without heating by means of a zinc-copper couple in acid solution, followed by dia/otisation of the amimo derivative and coupling to give an azo dye An alternative procedure la described in winch the parathion is trapped on cellulose powder containing zinc dust, from which the reduced derivative is directly cluted

Production of biomass with simultaneous wastewater treatment is feasible through recycling using algal culture. The productivity of such a system depends upon many parameters; two of them, turbulence and CO 2 regeneration, are studied here at the laboratory scale. Mechanical agitation with an air atmosphere over the culture leads to a low biomass production whereas bubbling with air produces a steady biomass increase, the rate of bubbling being less important than is suspected. Enrichment with 5% CO 2 in the bubbling air is an efficient way of obtaining a good biomass, but mechanical agitation of the algal culture with a 5% CO 2 : air mixture in a closed atmosphere over the culture is as good. Results are also presented on the relative effects of intermittent or continuous air bubbling.

The lignite deposits in Mississippi make up approximately 25 percent of the Gulf Coast deposit. To date, the limited number of studies on this lignite have chiefly been by Phillips Coal [1] and investigators in Mississippi [2,3]. This lignite, which is high in ash and moisture, was pyrolyzed in a 2.54 cm (1 in.) diameter fixed bed pyrolyzer under a helium atmosphere at temperatures ranging from 400°C to 950°C. The loss of volatile matter increased with increasing ultimate temperature producing weight losses 20–25% greater than the proximate analysis at 900°C. The yield of tar was found to decrease with temperature while volumetric gas production increased with the ultimate temperature. Hydrogen and carbon monoxide yields increased dramatically above 750°C. The maximum yield of gas was 375 ml/g daf lignite and was achieved at and above 815°C.

The metabolism of dicoumarol by rat liver microsomes from untreated and phenobarbital treated rats was studied. Following differential centrifugation of rat liver homogenates only the 104,000 g microsomal fraction supported dicoumarol metabolism. This was found to be strongly dependent on the presence of NADPH or a NADPH-generating system as well as oxygen and it was inhibited by CO. These data indicate that dicoumarol is metabolized by the mixed function oxidase of liver microsomes. The K m and V m for dicoumarol were determined using microsomes from untreated and phenobarbital treated rats. The values of K m were 5·0 × 10 −5 and 3·9 × 10 −5 M, respectively, while the corresponding values of V m were 0·9 and 2·3 nmoles/mg protein/min. The significance of these results is discussed.

This paper presents model results for the dispersion of radionuclides released into the atmosphere by intense forest fires in the Chernobyl Exclusion Zone in April 2020. The 137Cs activity concentration in the surface air is calculated on a regional scale (in Ukraine) and a local scale (within the Chernobyl Exclusion Zone). The 137Cs activity in the surface air of Kyiv was found to have reached 2–4 mBq m−3 during the period April 4–20. The results presented in this paper are generally consistent with measured data pertaining to radioactive contamination in Kyiv and areas around several nuclear power plants in Ukraine. The total effective dose to the population of Kyiv during the fire period was estimated to be 5.7 nSv from external exposure and the inhalation of 137Cs and 90Sr, rising to 30 nSv by the end of 2020. This is about 0.003% of the annual permissible level of exposure of the population. A committed effective dose of about 16 nSv was estimated for the personnel of the Chernobyl nuclear power plant from the inhalation of 137Cs and 90Sr during the 2020 forest fires. A method for estimating the radionuclide activity emissions during wildland fires in radioactively contaminated areas is proposed. This method is based on satellite measurement data of the fire radiative power, the radionuclide inventory in the fire area, and an emission factor for radioactive particles.

The main aim of this paper is to study the effects of humidity on the PV panel. In this paper, the panel performance was studied in the laboratory under varied humid atmosphere. The PV performance parameters were computed by measuring its output voltage and current, amount of solar radiation incident on the panel’s surface and its surface temperature by varying humidity levels artificially in the laboratory. From the studies it was observed that with rising humidity levels, solar insolation and panel power output decrease. With an increment of 50.15% in the humidity level, the panel power output reduces by 34.22%. Moreover, it was found that due to the increase in humidity from 65.40% to 98.20% the panel temperature got lowered by 11.40%.

Solar terrestrial radiations on the earth's surface range between 0.29 µ and 2.5 µm are available for Solar Photo-Voltaic (SPV) panels energy generation. The paper gives a critical review of the reduction in the electrical output due to dust depletion over the SPV and an experimental investigation which studies the SPV output energy response during the dust depletion. The performance of SPV gets profoundly impacted by the sand storms, pollution level, and snow accumulations. These challenges lower down the efficiency of the solar panels and negatively impacts electrical performance. In the given paper, the research review analyzes the effect of dust deposition on SPV. The reduction in electrical performance due to dust on SPV is a severe concern, and various mitigation techniques handle this issue. The study compares two SPVs with dust and without dust in the off-grid stand-alone system in simulated atmosphere in the laboratory, and the characteristics provide sufficient information for analyzing the electrical performance of considered SPVs. The experimental observations at various installation tilt angles show a remarkable impact on the normalized efficiencies and normalized short circuit current, whereas the normalized open-circuit voltage acts nearly inert in both conditions.

‘Thermal runaway’ was the most popular mechanism in flash sintering, but this theory was inappropriate under high electric field. In this paper, we described electric discharge and breakdown phenomena in experiment to verify this point. And water moisture was found an important role in conducting electric discharge, that increasing moisture content of samples decreased the onset electric field of flash sintering and as low as 1628 V/cm of onset electric field was realized in this paper. With high electric field that can induce electric discharge in the sample, the flash sintering can be induced at room temperature and atmosphere.

Freshwater bodies are found as significant sources of greenhouse gas to the atmosphere, but their quantitative significance is not yet clear. The rapid increase in hydropower dams and associated emissions has received much attention from hydropower industries, environmentalists, and policymakers from across the globe. The tropical/subtropical eco-regions are, particularly, considered as hotspots from greenhouse gas production point of view as the emitted gases are playing a critical role in climate change. The present paper reviews the uncertainty and limitations of greenhouse gas measurement from Chinese freshwater bodies based on available data. Literature reported that carbon dioxide emission from Chinese lakes falls in the range of 0.01–2.16 μmol m−2s−1 except for Poyang Lake. The CO2 emission from Chinese hydropower reservoirs is estimated as 0.15–1.11, while for rivers, it is 0.44–4.12 μmol m−2s−1. The methane and nitrous oxide emissions are, however, found less than carbon dioxide emission. The CO2 emission falls in the range of −0.17–0.54 and 1.08–1.70, respectively higher than global lakes and rivers, while the global reservoirs have emission in the range of −0.17–2.98 μmol m−2s−1. The paper also reports the challenges in the estimation and prediction of greenhouse gas emissions from hydropower reservoirs along with suggested mitigation measures.

The blade obtains its power by using the power of gases in addition to also the atmosphere that are at elevated temperatures and strain. You'll locate intense pressures made on mill blades signifying the toaster blades remain operating at elevated temperatures and strain. The pressures act on the blade as a result of angular prices, and also instant is. The paper is a review of analyses and there are an assortment of factors have an impact on on antenna. This paper is going to be helpful for anyone who are functioning in the industry of plants.

This paper presents an analysis of spectral impacts on mc-Si and new generation CdTe in two distinct regions of Brazil: Florianopolis-SC (27°S, 48°W) in the South, and Assu-RN (5°S, 37°W) in the Northeast. As utility-scale PV power plants are progressively being deployed in the Brazilian Northeast, the need for evaluation of the spectral effects of local blue-biased spectra on the energy yield of different PV technologies arises, as well as the need for spectral correction of field peak-power measurements done during commissioning and system performance tests. Considering the high cost of adequate spectral measurement equipment, this paper proposes a new approach for the estimation of spectral impacts without the need for in loco measurements. The proposed methodology consists of the use of satellite data acquired from NASA's Giovanni platform as inputs for the SMARTS 2.9.5 spectra model. Results for measured spectra showed that, for both locations, new generation CdTe (i.e. First Solar Series 4 and 6) has significant spectral gains: up to 10% for Assu-RN (Northeastern Brazil) and 2% for Florianopolis-SC (Southern Brazil). A seasonal variation could also be detected for the Florianopolis site, with lower spectral gains for CdTe - and higher for mc-Si - close to the Southern Hemisphere’s winter solstice, due to higher air mass values and lower precipitable water content of the atmosphere. The proposed method using Giovanni data and SMARTS spectra modeling produced very similar spectra to those measured for clear days in the field at both sites, yielding good results for the calculation of spectral factors for both mc-Si and CdTe. For days with a higher diffuse fraction the results were not as satisfactory, as expected. The proposed method was also applied to instantaneous measurements for three different times (and AM values) of the day for Florianopolis: 9:00, 12:00 and 15:00, yielding satisfactory results for IV curve spectral correction.

Problem of gas emission as NOX, SOX, heavy metals from fossil fuel combustion process is still under study. Especially the oxy-condition effect on gas emissions from oxy-fuel requires more analysis and research. This paper focuses on SO2 and SO3 behaviour investigation during air and oxy-fuel combustion processes, and formation of H2S and SO2 from N2 and CO2 atmosphere. The research focuses especially on Polish medium sulphur coals. In the paper selected brown coals were examined on the content of total sulphur. During the tests campaign one type of lignite, predried to Mraw = 15% was a subject of pyrolysis at 800 and 1000 °C under N2 and CO2 atmosphere, and further combusted in three different atmospheres: air atmosphere, and two different oxy atmospheres with O2/CO2 ratios, equal 25/75% and 30/70% (vol.). Tests were carried out on an isothermal flow reactors (IFR) in a large laboratory scale. The influence of the CO2 atmosphere in oxy-condition in comparison with to the air atmosphere on SO2, SO3 emission intensity was determined. The results showed that the change of atmosphere from the air atmosphere to oxy atmosphere and increase of oxygen concentration in O2/CO2 combustion atmosphere results in the increase of the conversion ratio of sulphur from solid phase to a the gas phase for the lignite. During the pyrolysis process it is mainly the H2S that is released in the gaseous form.

The production of silicon-calcium alloy is energy intensive (>10,000 kWh/t). This means that energy cost has a relevant influence in the price of the alloy. The utilization of concentrated solar energy in the synthesis of silicon-calcium alloy is proposed in this paper. Metallurgical quality silicon and limestone are used as starting materials (25 wt.%, 50 wt.% and 75 wt.% Si). After a 12 min treatment under power values of around 1 kW and without using special atmosphere, silicon-calcium was detected in all samples, although mixed with the products of reaction (Ca3Si2O7, Ca10O25Si6, SiO2). This last question means that there was not proper separation metal-slag, and it should be improved in future investigations. However, the basic knowledge presented in this paper could be of great interest for an industrial process based on the solar energy. This way, the energy costs could be reduced, the pollutant emissions could be minimized, and the competitiveness of the ferroalloys industry could be increased. Sin financiación 4.608 JCR (2019) Q2, 35/112 Energy & Fuels 1.537 SJR (2019) Q1, 32/297 Renewable Energy, Sustainability and the Environment, 62/626 Materials Science (miscellaneous) No data IDR 2019 UEM

Radon, known to be a human carcinogen, is one of the most concerned radionuclides in uranium mining which need to be monitored and controlled. A large amount of radon is discharged to the atmosphere mainly through underground ventilation shafts for underground uranium mining. There are many studies on radon release of uranium mine, but the differences of the measured radon results are very big. In this paper, a typical underground uranium mine in China is chosen as a case study. This study finds that distribution of radon concentration and airflow speed inside the ventilation shaft are extremely uneven, but the distributions are respectively stable and regular for a fixed cross-section at the wellhead depth of 0–1 m. There is also a stable numerical relationship between the radon release rate and the product of radon concentration and airflow speed at the center for any cross-section in the shaft. Based on this regulation, a multipoint interpolation-integration method and a one-point method for calculating radon release from underground ventilation shaft are proposed in this paper. The results show that the difference between these two methods is 2–10%, the one-point method is more suitable and convenient to be applied for the long-term monitoring radon release rate from uranium mine ventilation. The research results in this paper can be applied in the estimation of radon release rate for other underground uranium ventilation shafts.

PACKMAN (PArticle Counter k-index Magnetic ANomaly) is an autonomous, light and robust space weather instrument for operation within the subsurface, surface and atmosphere (as payload in stratospheric balloons) of the Earth. It has been designed using Commercial Off-The-Shelf (COTS) components to reduce the cost of each unit and to allow to have multiple units monitoring simultaneously at different sites and also incorporate an open-access citizen science approach. The hardware-core of each PACKMAN units, weights around 600 g and consumes about 500 mA of current at 12 V. PACKMAN has been deployed at multiple latitudes and altitudes ranging from stratospheric heights (corroborating its TRL8 maturity) to subsurface depths of around 1 km. The data from PACKMAN have been compared with the state-of-the-art ground-based observatories, and satellites and scientific observations have been documented. A 3-D network of PACKMAN units operating continuously around the globe, from the subsurface to the stratosphere, would help to improve the understanding of the space weather phenomena, and its implications on the climate and infrastructures. PACKMAN is also an excellent tool for education and outreach. This article outlines the building instructions of two types of PACKMAN units: PACKMAN-S for ground-based measurements and PACKMAN-B for stratospheric measurements aboard high-altitude balloons., The authors of the paper would like to acknowledge the Dark Matter Research facility, Boulby Mine, UK Center for Astrobiology, Zero2Infinity, Esrange and the Swedish Space Corporation (SSC) for their support to this collaborative initiative. The results presented in this paper have been compared with data collected at magnetic observatories. We thank the British Geological Survey for the open-access data from the magnetic observatories and GFZ Postdam for the Kp index data. The authors of the paper would also like to thank Miracle Israel Nazarious for his help with graphs. MPZ has been partially funded by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia “María de Maeztu”- Centro de Astrobiología (CSIC-INTA) and the Spanish Ministry of Science and Innovation (PID2019-104205GB-C21).