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Lignite with a high moisture content is needed to effectively remove water and maximally restrain the re-adsorption capacity of dewatered coal. The ambient gas during lignite drying is an important factor influencing the physical properties of dewatered samples. CO2 is the main component of exhaust gas, which has been reused in flash drying technology. The relationship between the drying characteristics of a typical Chinese lignite and the pore structure changes of dewatered coal in a CO2 atmosphere, and the effect on the behavior of re-adsorbing moisture were studied. Drying experiments of lignite samples under an Ar atmosphere were also carried out for comparison. The moisture re-adsorption experiments of dewatered coal samples were conducted at 30 °C under relative humidity of 75%. The results show that the drying efficiency of coal samples under a CO2 atmosphere is higher than that under an Ar atmosphere due to the swelling effect caused by the adsorption of CO2, but this difference between CO2 and Ar becomes gradually smaller with increase in the drying temperature. The dewatered coal sample obtained under a CO2 atmosphere shows a stronger ability to re-adsorb moisture caused by the swelling effect, which could be attributed to the changes of the structure of the coal sample in this atmosphere and the increase of the surface area where the moisture is primarily absorbed. The total moisture content in the coal sample after re-adsorbing moisture follows a linear relationship with the specific surface area of dewatered lignite.

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 .

In modified atmosphere packaging of guava, moisture scavenger (MS) sachet containing 30–50 g of coarse silica gel and ethylene scavenger (ES) sachet containing 0–4 g of potassium permanganate was added as per central composite rotatable design. The headspace O2 and CO2 of the packages were studied at 4, 8 and 12 °C for 30 days and thereafter the guava were left for two days to ripen at 30 °C. After that the chilling injuries, percentage acceptable guava, peel color and pulp texture was analyzed. After two days ripening at 30 °C the samples with 3 g ES and 46 g MS registered higher L∗, lower a∗ value & firmness (16.65 N), lowest chilling injury score. About 95% of guava was found acceptable in this treatment with 1.89–2.79% reducing sugar, 0.95–1.1% titrable acidity, 59% and 46.61% retention of total phenols and ascorbic acid respectively, resulting 32 days shelf-life of guava.

Torrefaction of oil palm empty fruit bunches (EFB) under combustion gas atmosphere was conducted in a batch reactor at 473, 523 and 573K in order to investigate the effect of real combustion gas on torrefaction behavior. The solid mass yield of torrefaction in combustion gas was smaller than that of torrefaction in nitrogen. This may be attributed to the decomposition enhancement effect by oxygen and carbon dioxide in combustion gas. Under combustion gas atmosphere, the solid yield for torrefaction of EFB became smaller as the temperature increased. The representative products of combustion gas torrefaction were carbon dioxide and carbon monoxide (gas phase) and water, phenol and acetic acid (liquid phase). By comparing torrefaction in combustion gas with torrefaction in nitrogen gas, it was found that combustion gas can be utilized as torrefaction gas to save energy and inert gas.

Summary This study highlights the dynamic nature of the temperature dependence of leaf respiration in plants experiencing future climate change scenarios, particularly with respect to drought and elevated [CO2]., Climate change is resulting in increasing atmospheric [CO2], rising growth temperature (T), and greater frequency/severity of drought, with each factor having the potential to alter the respiratory metabolism of leaves. Here, the effects of elevated atmospheric [CO2], sustained warming, and drought on leaf dark respiration (R dark), and the short-term T response of R dark were examined in Eucalyptus globulus. Comparisons were made using seedlings grown under different [CO2], T, and drought treatments. Using high resolution T–response curves of R dark measured over the 15–65 °C range, it was found that elevated [CO2], elevated growth T, and drought had little effect on rates of R dark measured at T

Lignite is a kind of coal that has high moisture content and needs to be dried before being utilized. The dried lignite will readsorb moisture during its storage. In this work, a typical Chinese lignite was dried by air at 120–180 °C and hydrothermally dewatered at 200–320 °C. The moisture adsorption isotherms of treated coal and the parent coal were obtained at 30 °C to investigate the essential moisture adsorption properties. Then the moisture readsorption performance of the studied coal in the real storage was simulated by placing the samples in the atmosphere and monitoring the evolution of the sample masses. The experimental results indicated that the moisture readsorption capacity of the air-dried lignite was lower than the parent coal and decreased with increasing drying temperature. For the hydrothermally dewatered coal, the moisture readsorption capacity increased with increasing dewatering temperature to 240 °C and then decreased significantly as dewatering temperature rose to 320 °C. The inhibi...

World is facing numerous environmental challenges, one of them being the increasing pollution both in theatmosphere and landfi lls. After the goods have been used, they are either buried or burnt. Both ways of disposalare detrimental and hazardous to the environment. The term biodegradation is becoming more andmore important, as it converts materials into water, carbon dioxide and biomass, which present no harm tothe environment. Nowadays, a lot of research is performed on the development of biodegradable polymers,which can “vanish” from the Earth surface after being used. In this respect, this research work was conductedin order to study the biodegradation phenomenon of cellulosic and non-cellulosic textile materials whenburied in soil, for them to be used in our daily lives with maximum effi ciency and after their use, to be disposedof easily with no harmful eff ects to the environment. This research indicates the time span of the uselife of various cellulosic and non-cellulosic materials such as cotton, jute, linen, fl ax, wool when used for thereinforcement of soil. The visual observations and applied microscopic methods revealed that the biodegradationof cellulose textile materials proceeded in a similar way as for non-cellulosic materials, the only differencebeing the time of biodegradation. The non-cellulosic textile material (wool) was relatively more resistantto microorganisms due to its molecular structure and surface.Keywords: biodegradation, composting, natural textile materials, FT-IR

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.

Several studies have attempted to determine the lower limit of atmospheric oxygen under which combustion can occur; however, none have been conducted within a fully controlled and realistic atmospheric environment. We performed experimental burns (using pine wood, moss, matches, paper, and a candle) at 20°C in O 2 concentrations ranging from 9 to 21% and at ambient and high CO 2 (2000 parts per million) in a controlled environment room, which was equipped with a thermal imaging system and full atmospheric, temperature, and humidity control. Our data reveal that the lower O 2 limit for combustion should be increased from 12 to 15%. These results, coupled with a record of Mesozoic paleowildfires, are incompatible with the prediction of prolonged intervals of low atmospheric O 2 levels (10 to 12%) in the Mesozoic.

The objective of this research was to study blending ratio effect on co-pyrolysis of Empty Palm Fruit Bunch (EPFB) and low quality coal using CO2 gas purge on the characteristics of gas, solid and liquid products. Characteristics of gas products consisting of H2 and CO2 gas concentration. Solid product characteristics consist of pore diameter, surface area, total pore volume, solid structure. Meanwhile, the characteristics of liquid products consist of liquid composition. EPFB and low quality coal were reduced to a maximum particle size of about 16 meshes at pre treatment process. The blending ratio of low quality coal and EPFB were 100/0, 80/20, 60/40, 40/60, 20/80 and 0/100, temperature at 500 °C. The result obtained that H2 gas increased between 0 % - 0.423 % due to the higher blending ratio. The concentration of CO2 gas was fluctuated. Meanwhile, pore diameter and total pore volume decreased due to the higher blending ratio. The pores diameter were 61.7316 nm and 18.8361 nm obtained at 0 % and 80 % EPFB, respectively. Total pore volumes were 0.0111 cm3/and 0.0063 cm3/g obtained at 0 % and 80 % EPFB, respectively. Surfaces area were increased, they were 0.72 m2/g and 1.3480 m2/g at 0 % and 80 % EPFB, respectively. Physical analysis was obtained that the higher of blending ratio (EPFB 100%), the more concentrated of reddish brown color. Liquid products identified contain 41 compounds with the dominant compound of the alkene group. The largest compound were hexadecane (23.69%) and heptacosane (22.61%).

Modified atmosphere drying of Flos Lonicerae is conducted, and the effects of drying temperature and oxygen content on drying characteristics and product quality are investigated in this study. Nitrogen gas is aerated into the dryer to adjust the oxygen content, and a heat pump system is used to control the drying temperature. The results showed that the increase in drying temperature and the decrease in oxygen content could improve the drying rate and effective moisture diffusivity. Increase in chlorogenic acid and chlorophyll contents as well as decrease in color difference were observed with decreasing drying temperature and oxygen content. High product quality could be achieved at all drying temperature levels when oxygen content was as low as 5%. Therefore, reducing oxygen content in the drying atmosphere is an effective method to improve product quality. Practical Application A modified atmosphere dryer equipped with a heat pump system is developed. The effects of drying parameters, including drying temperature and oxygen content, on drying characteristics and quality of Flos Lonicerae are studied. Nitrogen gas is used to replace certain portions of air to achieve different oxygen content levels in drying processes. The results show that drying under low oxygen content increases effective moisture diffusivity (Deff). It also promotes higher chlorogenic acid and chlorophyll contents as well as better product appearance. Therefore, modified atmosphere drying is a promising method to protect the quality of dried products. The results of this study are helpful to the technological application of modified atmosphere drying with heat pump system for Flos Lonicerae dehydration and preservation.

Recovery of elemental sulfur from zinc concentrate direct leaching residue (DLR) using atmospheric distillation was systematically investigated on a pilot-scale system for the first time. Batch operating mode was suggested for recovery of elemental sulfur from water-rich DLR using atmospheric distillation. Elemental sulfur with purity higher than 99% was obtained under certain conditions in batch operating mode. With an appropriate feed amount of 1,200 kg, batch experiment conducted at 460 degrees C resulted in sulfur purity of 96.22% and a recovery rate higher than 85%. Only 0.59 and 1.24 kWh power was needed to handle 1.0 kg DLR and produce 1.0 kg elemental sulfur, respectively. The results suggest that recovery of elemental sulfur from zinc concentrate DLR using atmospheric distillation is technologically and economically feasible. Moreover, other metal elements such as zinc were enriched in the distillation concentrate, which could be used for metal refining. Technologies could effectively lower the moisture content of DLR, and lowering the distillation temperature would be of great value for recovery of elemental sulfur from DLR using a distillation method.Distillation is a promising solution for recovery of elemental sulfur from DLRs. This work revealed the possibility of separation of elemental sulfur from zinc concentrate DLR using atmospheric distillation. Such knowledge is of fundamental importance in developing field-scale separation and purification technologies and devices in which simultaneous sulfur recovery and precious metal enrichment are possible. Important tasks for follow-up research are also suggested.

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.

We firstly report a facile approach to produce few-layered graphene sheets by low-temperature (130 °C) exfoliation and reduction of graphite oxide under ambient atmosphere with the aid of HCl. The obtained graphene materials exhibited high BET specific surface area (∼500 m2 g−1) and excellent electrical conductivity (∼1200 S m−1).

Ab initio calculations at the G2 level were used in a theoretical description of the kinetics and mechanism of the hydrogen abstraction reactions from fluoro-, chloro- and bromomethane by chlorine atoms. The profiles of the potential energy surfaces show that mechanism of the reactions under investigation is complex and consists of two - in the case of CH3F+Cl - and of three elementary steps for CH3Cl+Cl and CH3Br+Cl. The heights of the energy barrier related to the H-abstraction are of 8–10 kJ mol−1, the lowest value corresponds to CH3Cl+Cl and the highest one to CH3F+Cl. The rate constants were calculated using the theoretical method based on the RRKM theory and the simplified version of the statistical adiabatic channel model. The kinetic equations derived in this study\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \begin{array}{*{20}c} {k\left( {\mathrm{C}{{\mathrm{H}}_3}\mathrm{F}+\mathrm{Cl}} \right)=6.75\times 1{0^{-12 }}\times {{{\left( {\mathrm{T}/300} \right)}}^{2.12 }}\times\exp (-900/\mathrm{T})}{\mathrm{c}{{\mathrm{m}}^3}\mathrm{molecul}{{\mathrm{e}}^{-1 }}{{\mathrm{s}}^{-1 }}} \\ {k\left( {\mathrm{C}{{\mathrm{H}}_3}\mathrm{Cl}+\mathrm{Cl}} \right)=6.97\times 1{0^{-12 }}\times {{{\left( {\mathrm{T}/300} \right)}}^{1.73 }}\times\exp (-795/\mathrm{T})}{\mathrm{c}{{\mathrm{m}}^3}\mathrm{molecul}{{\mathrm{e}}^{-1 }}{{\mathrm{s}}^{-1 }}} \\ {k\left( {\mathrm{C}{{\mathrm{H}}_3}\mathrm{Br}+\mathrm{Cl}} \right)=6.26\times 1{0^{-12 }}\times {{{\left( {\mathrm{T}/300} \right)}}^{1.82 }}\times\exp (-795/\mathrm{T})}{\mathrm{c}{{\mathrm{m}}^3}\mathrm{molecul}{{\mathrm{e}}^{-1 }}{{\mathrm{s}}^{-1 }}} \\ \end{array} $$\end{document}and\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \begin{array}{*{20}c} {k\left( {\mathrm{C}{{\mathrm{H}}_2}\mathrm{F}+\mathrm{HCl}} \right)=2.88\times 1{0^{-13 }}\times {{{\left( {\mathrm{T}/300} \right)}}^{2.02 }}\times\exp (-1255/\mathrm{T})}{\mathrm{c}{{\mathrm{m}}^3}\mathrm{molecul}{{\mathrm{e}}^{-1 }}{{\mathrm{s}}^{-1 }}} \\ {k\left( {\mathrm{C}{{\mathrm{H}}_2}\mathrm{Cl}+\mathrm{HCl}} \right)=2.42\times 1{0^{-13 }}\times {{{\left( {\mathrm{T}/300} \right)}}^{1.57 }}\times\exp (-2100/\mathrm{T})}{\mathrm{c}{{\mathrm{m}}^3}\mathrm{molecul}{{\mathrm{e}}^{-1 }}{{\mathrm{s}}^{-1 }}} \\ {k\left( {\mathrm{C}{{\mathrm{H}}_2}\mathrm{Br}+\mathrm{HCl}} \right)=2.21\times 1{0^{-13 }}\times {{{\left( {\mathrm{T}/300} \right)}}^{1.69 }}\times\exp (-1485/\mathrm{T})}{\mathrm{c}{{\mathrm{m}}^3}\mathrm{molecul}{{\mathrm{e}}^{-1 }}{{\mathrm{s}}^{-1 }}} \\ \end{array} $$\end{document}allow a description of the kinetics of the reactions under investigation in the temperature range of 200–3000 K. The kinetics of reactions of the entirely deuterated reactants were also included in the kinetic analysis. Results of ab initio calculations show that D-abstraction process is related with the energy barrier of 5 kJ mol−1 higher than the H-abstraction from the corresponding non-deuterated reactant molecule. The derived analytical equations for the reactions, CD3X+Cl, CH2X+HCl and CD2X+DCl (X = F, Cl and Br) are a substantial supplement of the kinetic data necessary for the description and modeling of the processes of importance in the atmospheric chemistry.

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.

Metaproteomic analysis of air particulate matter provides information about the abundance and properties of bioaerosols in the atmosphere and their influence on climate and public health. We developed and applied efficient methods for the extraction and analysis of proteins from glass fiber filter samples of total, coarse, and fine particulate matter. Size exclusion chromatography was applied to remove matrix components, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied for protein fractionation according to molecular size, followed by in-gel digestion and LC-MS/MS analysis of peptides using a hybrid Quadrupole-Orbitrap MS. Maxquant software and the Swiss-Prot database were used for protein identification. In samples collected at a suburban location in central Europe, we found proteins that originated mainly from plants, fungi, and bacteria, which constitute a major fraction of primary biological aerosol particles (PBAP) in the atmosphere. Allergenic proteins were found in coarse and fine particle samples, and indications for atmospheric degradation of proteins were observed. Graphical abstract Workflow for the metaproteomic analysis of atmospheric aerosol samples Electronic supplementary material The online version of this article (doi:10.1007/s00216-016-9747-x) contains supplementary material, which is available to authorized users.

This paper uses a lifecycle analysis to trace the fate of carbon bound in wood products until most of the carbon is released back into the atmosphere. A sensitivity analysis has been carried out to find the effect of change in terminal use (recycling, land filling and burning of discarded products), half-life of wood products and decay rate of carbon in landfills. Of the total carbon harvested from forests in India, about 90% is released into the atmosphere in the first year, due to burning of fuelwood; at the end of 100 years, about 0.8% still remains in the wood products. The sensitivity analysis shows that the length of the lifespan of wood products has only a marginal effect on the amount of carbon sequestered but has significant effect on the amount of carbon in products in use. Thus an important conclusion from this scenario is that by increasing the durability of the wood products, carbon can be locked over a period equal to the time needed to grow the timber for these products. Further, the carbon storage is affected more significantly by the decay rate of carbon in landfills than the proportion of products recycled. The study also shows that wood products can be important stores of carbon, but only if they can substitute for a unit of carbon emitted by burning fossil fuels. Such a lifecycle analysis has the potential to account completely for carbon stock changes in the wood products, where and when they are occurring, and explain how they are occurring.

In celebrating the 70th birthday of Giorgio Fiocco we recall that his scientifi c production includes some pioneering work in a number of fi elds where he set important milestones. In particular, several of his papers represent the fi rst published evidence in certain fi elds and triggered such a large fl ow of research, new developments and new paper production that the original source is almost forgotten. Here the topics where his contribution was of pioneering importance are briefl y recalled and his original works cited.

This work investigated the bio-oil production from oil palm empty fruit bunch (EFB) by continuous pyrolysis reactor under nitrogen and steam atmospheres as sweeping gas. The study parameters were particle size, biomass feeding rate, reactor temperature, and reactor sweeping gas. The EFB particle ranges were below 500 micrometers, between 500 - 1180 micrometers and 1180 - 2230 micrometers. Feeding rates were 150, 350, and 550 rpm. Both factors were analyzed by single factor ANOVA. Additionally, Box-Behnken design was used to investigate temperature (350oC - 600oC) under the following nitrogen and steam flow rates as sweeping gas: 0, 100, and 200 cm3/min of nitrogen and 0, 9, and 18 cm3/min of steam. The mathematical model from Box-Behnken design succeeded in predicting the optimal conditions for normal and nitrogen atmospheres. A particle size below 1180 μm was determined to be optimal for bio-oil production. In a normal atmosphere or no sweeping gas, the condition was 475oC and 450 rpm of feed rate. The optimal condition for nitrogen atmosphere was 530oC, 450 rpm of feed rate, and 200 cm3/min of nitrogen flow rate. However, steam as sweeping gas caused high uncertainty and the model was unable to predict the optimal conditions accurately. The biooils from normal, nitrogen, steam, and mixed atmospheres were analyzed for general characteristics. NMR and GC-MS were used to analyze chemical compositions in the bio-oils. Relationships between physical and chemical characteristics were determined and discussed.

Birch pollen is one of the main causes of allergy during spring and early summer in northern and central Europe. The aim of this study was to create a forecast model that can accurately predict daily average concentrations of Betula sp. pollen grains in the atmosphere of Szczecin, Poland. In order to achieve this, a novel data analysis technique—artificial neural networks (ANN)—was used. Sampling was carried out using a volumetric spore trap of the Hirst design in Szczecin during 2003–2009. Spearman’s rank correlation analysis revealed that humidity had a strong negative correlation with Betula pollen concentrations. Significant positive correlations were observed for maximum temperature, average temperature, minimum temperature and precipitation. The ANN resulted in multilayer perceptrons 366 8: 2928-7-1:1, time series prediction was of quite high accuracy (SD Ratio between 0.3 and 0.5, R > 0.85). Direct comparison of the observed and calculated values confirmed good performance of the model and its ability to recreate most of the variation.

Carbon dioxide (CO2), which is produced largely in petrochemical processes, is the most prominent greenhouse gas in Earth's atmosphere. In this study, a process including CO2 recovery from flue gases was simulated and optimized by using alkanolamines in a petrochemical plant in Iran. The amount of CO2 recovery, amine consumption, mechanical and operational characteristics of the absorption column, CO2 purity in the stripper column effluent, required energy of the stripper, and mechanical and operational features of the stripper were reported as simulation results. The results showed that monoethanolamine (MEA) is capable of recovering 100% of CO2 from absorption column feed and its consumption is considerably less than other alkanolamines.

Soil dust is a major constituent of airborne particles in the global atmosphere. Dust plumes frequently cover huge areas of the earth; they are one of the most prominent and commonly visible features in satellite imagery. Dust is believed to play a role in many biogeochemical processes, but the importance of dust in these processes is not well understood because of the dearth of information about the global distribution of dust and its physical, chemical, and mineralogical properties. This paper describes some features of the large-scale distribution of dust and identifies some of the geological characteristics of important source areas. The transport of dust from North Africa is presented as an example of possible long-range dust effects, and the impact of African dust on environmental processes in the western North Atlantic and the southeastern United States is assessed. Dust transported over long distances usually has a mass median diameter

Capsicum shreds were stored under modified atmosphere packaging in differentially perforated and nonperforated packages at 5 and 15C. Chlorophyll was largely maintained at both storage temperatures in perforated packages having two macroperforations. Maintenance of chlorophyll in nonperforated packages was not considered to be beneficial in view of anaerobic environment at 15C, which affected other qualitative constituents adversely. While the ascorbic acid deteriorated at a faster rate in nonperforated packages at both temperatures, it was better retained in all perforated packages. A decrease in storage temperature to 5C resulted in rapid oxidation of phenolic content, while it was hampered in nonperforated packages. Because all the objectively assessed qualitative characteristics could not be maintained under a single gas condition, subjectively evaluated sensory ratings could point out that in-pack atmosphere under two perforations could be used for a storage period of 5 days under simulated storage environment. PRACTICAL APPLICATIONS Minimally processed capsicum has high rates of respiration and due to non-utilization of standardized packaging has a shorter shelf life at the retail shelves and, thereafter, at the consumer level. This research has focused on application of modified atmosphere technology under simulated storage environment at the retailer and then at the customer level for minimally processed capsicum shreds. The results of the study have implied that a shelf life of 5 days from processing to consumption along with maintenance of various physicochemical constituents can be attained using the perforated packaging instead of the conventional nonperforated packages being used commercially. These results have potential application at the level of processer and retailer engaged in the postharvest chain of capsicum processing. Utilization of the results of this research is likely to aid them to standardize the packaging of capsicum shreds and maintain its better shelf life and various physicochemical constituents.

Refrigerator chill compartments with volumes of 22-L were fabricated, which had different gas tightness properties to gas or water vapor, ranging from 1,770 to 107,000 mL/hr·m2·atm in CO2 permeance at 25°C. Those compartments were filled with prepared fresh vegetables, and then their ability to preserve the quality at 3°C for 14 days was compared. The internal atmosphere and humidity were monitored together with the stored produce quality. The air-tight compartment with the lowest permeance created an atmosphere slightly different from air (CO2 0.8–1.6%; O2 19.7–20.4%), while the other ones had atmospheres of normal air. The relative humidity of the compartments ranged from 52 to 97%. Two air-tight compartments, maintaining a relative humidity mostly higher than 95%, preserved the produce better than the conventional open type one, with reduced weight loss and better retentions of ascorbic acid and chlorophyll.

In this study, torrefaction via microwave irradiation was introduced towards oil palm empty fruit bunches (EFB) samples. The samples was fed into the alumina type crucible inside the microwave with the power input limit at 385W. Experimental was carried in non-oxidative atmosphere at 50 ml/min continous flow of nitrogen gas into the torrefaction system. The effects of main parameters from temperature, residence time were studied towards mass yield, energy yield, proximate analysis and hydrophobicity percentage Result revealed the increased of energy value up to 22.4MJ/kg for torrefied samples, whereby from proximate analysis mark the increased of fixed carbon percentage whilst volatile matter decreased. Torrefaction products also shows the ability of reducing of moisture uptake up to 60%, which is prudent the good grindability.

Organically grown apples cv. Pinova harvested at two different dates were stored at 1.3 degrees C for up to 4 months in air, up to 7 months in ULO (1.5 kPa of O(2) and 1.3 kPa of CO(2)) and in dynamic controlled atmosphere (DCA) conditions (0.4-0.6 kPa of O(2) and 0.6-0.8 kPa of CO(2)); the DCA storage method involved the use of a chlorophyll fluorescence monitoring system in order to detect low-O(2) stress in apples and to allow for the dynamic adaptation of storage atmosphere to O(2) levels that were lower than in ULO but still tolerated by fruits. A postharvest 1-MCP treatment (for 24 h at 1.3 degrees C) and a hot water treatment (for 180 s at 50 degrees C) were also tested on apples stored afterward in ULO and air, respectively. Volatile compounds isolated from the pulp of fruits were measured after 4 and 7 months, just upon removal from storage and after 11 days at 22 degrees C. Total amount of aroma compounds detected in apples stored in DCA was markedly higher (from 2- to 4-fold) than in fruits exposed to 1-MCP + ULO but, at most sampling times, significantly lower than in ULO fruits. Moderate differences in storage atmosphere composition between ULO and DCA significantly affected both total amount and profile of volatile esters. Analogous effects were observed on the alcohol precursors of the main esters. Exposure to 1-MCP inhibited biosynthesis of straight-chain esters more than that of branched-chain esters. The hot water treatment did not seem to produce marked changes in volatile composition after four months of air storage, except for a sharp accumulation of aldehydes during the shelf-life time. DCA storage technology, besides avoiding any chemical treatment, can preserve apple aroma compounds better than 1-MCP + ULO during long-term storage.

Summary A retail package system was used to study the atmosphere modification which developed within packages of shredded Iceberg lettuce, sealed in trays with a range of polymer films of different gas permeabilities (oxygen permeability of 3000 to 10,000 ml/m2/day/atm. at 25°C). Modified atmospheres were produced both naturally by respiration, and by application of gas flushing techniques. The effects of these modified atmosphere conditions on visual and sensory quality of shredded lettuce was observed by monitoring colour change and development of off-odours. An equilibrated modified atmosphere containing 1–3% O2 and 5–6% CO2was established with 35 um low density polyethylene film after flushing with 5% O2, 5% CO2 in N2. This resulted in a shelf-life of approximately 14 days at 5°C, almost double that of the controls.

In this work, an active coating and modified atmosphere packaging (MAP) were investigated to prolong the shelf life of Fiordilatte packaged in traditional brine. First, the screening of MAP was performed in order to select the best gas composition. Then, the combined effect of MAP and coating was investigated. Finally, the coating was loaded with potassium sorbate and its effects under MAP conditions were also assessed. Results highlighted that MAP was able to control growth of the main spoilage microbial group (Pseudomonasspp.); however, the solubilisation of carbon dioxide into the brine compromised Fiordilatte texture. Therefore, the presence of the active coating avoided the damage of gas solubilisation and promoted a shelf life prolongation by about 157%.

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.

Dry deposition of gases plays an important role for the deterioration of stone materials and a better understanding of the processes involved will improve our ability to maintain stone monuments and buildings. As a part of an EU-project an investigation with four calcareous stone types have been exposed outdoor at two test sites in Norway for two years. The exposure has been carried out in sheltered position and the amount of reaction products and the penetration depth of SO2 into the stones was determined as soluble sulphate after half a year and after one and two years. Even if most of the sulphate was found in the upper 0.3 mm of the stone, there was an increase in the sulphate content in stone even down to the center of the stone sample. In laboratory tests with SO2, NO2 and changing relative humidity the synergistic effect of NO2 and the importance of the relative humidity was investigated. The uptake rates were calculated from the laboratory studies by analyzing the gas concentrations before and after the exposure chamber. By calculating the deposition velocity from the field study by using the amount of sulphate found in the stones together with the average outdoor concentration of SO2 at the test sites, the values were a magnitude higher than in the laboratory test, highest at the industrial paper mill sites with high concentrations both of SO2 and some hypochlorite and lower in urban atmosphere with fairly low values of SO2 and high values of NO2.

The aim of this research was to investigate the effects of pressure on aerobic biological wastewater treatment processes. For the purpose of the investigation two specially designed, identical, laboratory-scale rotating biological contactor (RBC) units were constructed. One of these was held in a steel pressure vessel while the other, as reference unit, was operated open to the atmosphere. The treatment capabilities of the pressurized unit, compared to those of the reference unit, were determined for a variety of organic loading rates at a 5-bar pressure. The unit under pressure was able to produce a much better effluent, in comparison with the reference unit when operating at higher loading conditions. The filtered BOD5 in the effluent from the unit under pressure was always less than 10 mgL−1, whereas the sludge yield coefficient was as low as 0.21 kg dry solids/kg BOD5 removed, even with the unit loaded even at an organic loading rate of 27.0 g BOD5/m2 · day. However, the development of the nitrificati...

Given the need for a light source, cyanobacteria and other photosynthetic microorganisms can be difficult and expensive to grow in large quantities. Lighted growth chambers and incubators typically cost 50-100% more than standard microbiological incubators. Self-shading of cells in liquid cultures prevents the growth of dense suspensions. Growing liquid cultures on a shaker table or lighted shaker incubator achieves greater cell densities, but adds considerably to the cost. For experiments in which gases other than air are required, the cost for conventional incubators increases even more. We describe an apparatus for growing photosynthetic organisms in exotic atmospheres that can be built relatively inexpensively (approximately 100 dollars U.S.) using parts available from typical hardware or department stores (e.g., Wal-mart or K-mart). The apparatus uses microfiltered air (or other gases) to aerate, agitate, and mix liquid cultures, thus achieving very high cell densities (A7503). Because gases are delivered to individual culture tubes, a variety of gas mixes can be used without the need for enclosed chambers. The apparatus works with liquid cultures of unicellular and filamentous species, and also works with agar slants.

An intensified array camera has been used to image weakly luminous flames spreading over thermally thin paper samples in a low-gravity environment aboard the NASA-Lewis Learjet. The aircraft offers 10 to 20 sec of reduced gravity during execution of a Keplerian trajectory and allows the use of instrumentation that is delicate or requires higher electrical power than is available in drop towers. The intensified array camera is a charge intensified device type that responds to light between 400 and 900 nm and has a minimum sensitivity of 10(exp 6) footcandles. The paper sample, either ashless filter paper or a lab wiper, burns inside a sealed chamber which is filled with 21, 18, or 15 pct. oxygen in nitrogen at one atmosphere. The camera views the edge of the paper and its output is recorded on videotape. Flame positions are measured every 0.1 sec to calculate flame spread rates. Comparisons with drop tower data indicate that the flame shapes and spread rates are affected by the residual g level in the aircraft.

Acoustic sounding is used routinely to investigate atmospheric structure and wind profiles in the lower atmosphere. This short paper draws attention to the fact that airborne insects are often very abundant at these altitudes, and may make significant contributions to acoustic returns

The effects of sodium sulfate in fuel oil and salty atmospheric air on the emission characteristics of furnaces or boilers burned with emulsified diesel oils are considered in this study. An industrial cylindrical furnace made of stainless steel associated with an automatic oil-fired burner was used for the emission measurements. Both neat diesel oil and emulsified diesel oil with distilled water were used as the tested oils. A homogenizing and emulsifying machine was employed to stir the diesel oil and sodium sulfate powder into a homogeneous oil mixture, and to prepare emulsions of micro-droplets of water dispersed in diesel oil. The experimental results showed that the existence of sodium chloride in atmospheric air enhanced SO2 formation. The use of emulsified diesel oil with 300-ppm sodium sulfate as fuel reduced the burning gas temperature and NOx emission while increased O2 emission. Moreover, the presence of sodium chloride in atmospheric air hindered the completeness of the combustion process and thus resulted in lower burning efficiency and larger excess oxygen emission.

Carbon dioxide (CO(2)) is a colorless gas that exists at a concentration of approximately 330 ppm in the atmosphere and is released in great quantities when fossil fuels are burned. The current flux of carbon out of fossil fuels is about 600 times greater than that into fossil fuels. With increased concerns about global warming and greenhouse gas emissions, there have been several approaches proposed for managing the levels of CO(2) emitted into the atmosphere. One of the most understudied methods for CO(2) mitigation is the use of biological processes in engineered systems such as photobioreactors. This research project describes the effectiveness of Chlorella vulgaris, used in a photobioreactor with a very short gas residence time, in sequestering CO(2) from an elevated CO(2) airstream. We evaluated a flow-through photobioreactor's operational parameters, as well as the growth characteristics of the C. vulgaris inoculum when exposed to an airstream with over 1850 ppm CO(2). When using dry weight, chlorophyll, and direct microscopic measurements, it was apparent that the photobioreactor's algal inoculum responded well to the elevated CO(2) levels and there was no build-up of CO(2) or carbonic acid in the photobioreactor. The photobioreactor, with a gas residence time of approximately 2 s, was able to remove up to 74% of the CO(2) in the airstream to ambient levels. This corresponded to a 63.9-g/m(3)/h bulk removal for the experimental photobioreactor. Consequently, this photobioreactor shows that biological processes may have some promise for treating point source emissions of CO(2) and deserve further study.

Thirty years ago, E. N. Lorenz provided some approximate limits to atmospheric predictability. The details—in space and time—of atmospheric flow fields are lost after about 10 days. Certain gross flow features recur, however, after times of the order of 10–50 days, giving hope for their prediction. Over the last two decades, numerous attempts have been made to predict these recurrent features. The attempts have involved, on the one hand, systematic improvements in numerical weather prediction by increasing the spatial resolution and physical faithfulness in the detailed models used for this prediction. On the other hand, theoretical attempts motivated by the same goal have involved the study of the large-scale atmospheric motions' phase space and the inhomogeneities therein. These “coarse-graining” studies have addressed observed as well as simulated atmospheric data sets. Two distinct approaches have been used in these studies: the episodic or intermittent and the oscillatory or periodic. The intermittency approach describes multiple-flow (or weather) regimes, their persistence and recurrence, and the Markov chain of transitions among them. The periodicity approach studies intraseasonal oscillations, with periods of 15–70 days, and their predictability. We review these two approaches, “particles” vs. “waves,” in the quantum physics analogy alluded to in the title of this article, discuss their complementarity, and outline unsolved problems.

It has been known since 1851 that atmospheric oxygen is taken up by the human epidermis. The contribution to total respiration is negligible. Until now the significance for the local oxygen supply of the skin has remained unknown. With a newly developed sensor, the oxygen fluxoptode, it has become possible to make local measurements of the transcutaneous oxygen flux (tcJ(O2)). In this study the sensor was calibrated so that absolute values of tcJ(O2) could be reported. At rest, tcJ(O2) was determined on normal, humidified skin on the volar forearm of 20 volunteers of different age groups. In order to evaluate the contribution of the blood flow to the oxygen supply of the skin, tcJ(O2) was recorded at the end of a 5 min suprasystolic occlusion of the forearm. At normal skin surface partial oxygen pressure (163 +/- 9 Torr), tcJ(O2) was 0.53 +/- 0.27 ml O2 min(-1) x m(-2). A 5 min interruption of blood flow resulted in an increase of 9.5 +/- 6.3 % in tcJ(O2). The value of tcJ(O2) was unaffected by the age of the subject. Published data on the oxygen diffusion properties of skin and simulations of intracutaneous profiles of oxygen partial pressure indicated that under these conditions, the upper skin layers to a depth of of 0.25-0.40 mm are almost exclusively supplied by external oxygen, whereas the oxygen transport of the blood has a minor influence. As a consequence, a malfunction in capillary oxygen transport cannot be the initiator of the development of superficial skin defects such as those observed in chronic venous incompetence and peripheral arterial occlusive disease.

A series of three experiments were conducted to develop a retail packaging system suitable for use in centralized meat processing and packaging operations using modified atmosphere master packaging (MAP) of display-ready beef and pork cuts. It was shown that oxygen (O 2 ) scavengers were needed inside retail trays, lidded or over-wrapped trays could be used with equal success but inclusion of a grid inside the retail tray was not required. It was established that a minimum of eight O 2 scavengers with an O 2 absorption rate high enough to achieve an O 2 half-life of 0.6-0.7 h in the pack atmosphere were needed where the O 2 concentration could otherwise remain ≤500 ppm at any time during storage. Composite results from these experiments clearly showed that the best performance resulted from use of hard plastic retail trays containing eight O 2 scavengers, with high O 2 absorption rate, when placed underneath an absorbent pad and over-wrapped with an O 2 permeable film. Small holes in two corners of the O 2 permeable film to permit free exchange of atmospheres within the retail packages facilitated O 2 reduction during MAP storage.

Highlight Photosynthetic acclimation of Eucalyptus globulus leaves to elevated CO2 was underpinned by reduced leaf N and Rubisco contents; the opposite occurred under warming, coinciding with growth resumption in spring., Leaf-level photosynthetic processes and their environmental dependencies are critical for estimating CO2 uptake from the atmosphere. These estimates use biochemical-based models of photosynthesis that require accurate Rubisco kinetics. We investigated the effects of canopy position, elevated atmospheric CO2 [eC; ambient CO2 (aC)+240 ppm] and elevated air temperature (eT; ambient temperature (aT)+3 °C) on Rubisco content and activity together with the relationship between leaf N and Vcmax (maximal Rubisco carboxylation rate) of 7 m tall, soil-grown Eucalyptus globulus trees. The kinetics of E. globulus and tobacco Rubisco at 25 °C were similar. In vitro estimates of Vcmax derived from measures of E. globulus Rubisco content and kinetics were consistent, although slightly lower, than the in vivo rates extrapolated from gas exchange. In E. globulus, the fraction of N invested in Rubisco was substantially lower than for crop species and varied with treatments. Photosynthetic acclimation of E. globulus leaves to eC was underpinned by reduced leaf N and Rubisco contents; the opposite occurred in response to eT coinciding with growth resumption in spring. Our findings highlight the adaptive capacity of this key forest species to allocate leaf N flexibly to Rubisco and other photosynthetic proteins across differing canopy positions in response to future, warmer and elevated [CO2] climates.

CO2 adsorption in Li-, Na-, K-CHA (Si/Al=6,=12), and silica chabazite zeolites was investigated by powder diffraction. Two CO2 adsorption sites were found in all chabazites with CO2 locating in the 8-membered ring (8MR) pore opening being the dominant site. Electric quadrupole-electric field gradient and dispersion interactions drive CO2 adsorption at the middle of the 8 MRs, while CO2 polarization due to interaction with cation sites controls the secondary CO2 site. In Si-CHA, adsorption is dominated by dispersion interactions with CO2 observed on the pore walls and in 8 MRs. CO2 adsorption complexes on dual cation sites were observed on K-CHA, important for K-CHA-6 samples due to a higher probability of two K(+) cations bridging CO2. Trends in isosteric heats of CO2 adsorption based on cation type and concentration can be correlated with adsorption sites and CO2 quantity. A decrease in the hardness of metal cations results in a decrease in the direct interaction of these cations with CO2.

Bio-char is a carbon-enriched and porous material produced from a variety of biomass. When bio-char is produced from biomass, approximately 50 % of the carbon that the plants absorbed as CO2 from the atmosphere is “fixed” in the charcoal. Bio-char is similar in its appearance to charcoal and activated carbon.

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 application of low oxygen through modified atmosphere packaging (MAP) is a technique used successfully to preserve the visual quality of lettuce and some other commodities. The expansion of use of low O2 via MAP to preserve quality of most commodities is limited by technical difficulties achieving target O2 concentrations, adverse physiological responses to low O2, and lack of beneficial responses to low O2. Low O2 often is not used simply because the physiological responses governed by the gas are not limiting quality maintenance. For instance, shelf life may be governed by decay susceptibility, which is largely unaffected by low O2 and may actually be exacerbated by the conditions encountered in hermetically sealed packages. Physiological processes influenced by low O2 and limit storability are discussed. The interdependence of O2 concentration, O2 uptake by the product, and temperature are discussed relative to requirements for packaging films.

The discoloration produced by the exposure of plastics to a polluted atmosphere containing nitrogen oxides and other gases is well known. New formulations with increased resistance to such discoloration require reliable accelerated tests for characterization of additives and products. The new procedure is based on an exposure of plastics to an atmosphere with a controlled concentration of nitrogen dioxide and evaluation of subsequent discoloration by optical measurements.

Although several per cent of net carbon assimilation can be re-released as isoprene emissions to the atmosphere by many tropical plants, much uncertainty remains regarding its biological significance. In a previous study, we detected emissions of isoprene and its oxidation products methyl vinyl ketone (MVK) and methacrolein (MACR) from tropical plants under high temperature/light stress, suggesting that isoprene is oxidized not only in the atmosphere but also within plants. However, a comprehensive analysis of the suite of isoprene oxidation products in plants has not been performed and production relationships with environmental stress have not been described. In this study, putative isoprene oxidation products from mango (Mangifera indica) branches under abiotic stress were first identified. High temperature/light and freeze-thaw treatments verified direct emissions of the isoprene oxidation products MVK and MACR together with the first observations of 3-methyl furan (3-MF) and 2-methyl-3-buten-2-ol (MBO) as putative novel isoprene oxidation products. Mechanical wounding also stimulated emissions of MVK and MACR. Photosynthesis under 13CO2 resulted in rapid (

In the gas chromatographic (GC) analysis of hydrocarbons in the ambient atmosphere, a Nafion® dryer was used in the sample preconcentration unit to remove moisture from the sample stream. We found that regenerating the Nafion® dryer by heating before analysis could cause losses and rearrangements of some hydrocarbon compounds in the sample. The degree of the losses and rearrangements was dependent on the length of time and the temperature used to regenerate the dryer, as well as the humidity of the sample. The effect of the regenerated dryer on the sample diminished when the dryer was purged with clean, dry nitrogen for several hours.

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.