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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 (

Pollutant gases from industries and certain processes like welding, exhaust of internal combustion engines, use of explosives, use of nitric acid, etc., are the sources of sulfur dioxide (SO2) and nitrogen oxides (NO2 and N2O5) which become the part of atmosphere. The heterogeneous reactions of atmospheric aerosol convert these gases to sulphuric, nitrous, and nitric acids which precipitate as acid rain and thus severely affect human health. In this paper, the design of colorimetric paper-based microfluidic device is presented to detect and quantify nitrogen dioxide (NO2). In order to reduce the cost of device and ease of fabrication, wax printing for fabricating paper-based analytical device (µPAD) is proposed.

The critical comments to the publications by the authors ofthe present paper that were given in [10] (the publications deal with the possible effects of gravity field inhomogeneities in the atmosphere and ocean) are discussed. In the authors' opinion, some remarks are groundless. At the same time, the authors agree with one of the important remarks that the results of their paper concerning studies of the ocean disturbances are to be reconsidered.

Investigation of the difference in the ageing process for several thermally upgraded and non-upgraded papers in transformer oil was performed. We observed that the level of nitrogen in the papers is crucial for the resistance towards hydrolysis. One of the papers in the experiment did not fulfil the upgrade specification with respect to the nitrogen level (data sheet). For hydrolysis of wet oil impregnated samples in argon atmosphere the upgraded papers seem to degrade less than non-upgraded papers. The paper with highest level of nitrogen degrades less than those with lower levels. The Insuldur process seems to be the best way of thermally upgrading the paper (Upgrade 1) and this also gives the highest level of nitrogen. For one of the upgraded samples (Upgrade 2) the nitrogen disappears completely after startup and this paper behaves as non-upgraded for the highest temperature. Dry oil impregnated paper (0.2% water content) under argon atmosphere does not seem to be hydrolysed and ages at a very slow rate. In the case of oxidation of dry oil impregnated samples (0.2% water content) in air there are initially no significant difference between non-upgraded and upgraded papers. However, the upgraded papers seem to have an improved performance after the water production from ageing becomes significant. The oxidation activation energy for non-upgraded paper is lower compared to hydrolysis and for upgraded paper this difference is smaller.

Pyrolysis volatiles and the environmental impact of printing paper in an air atmosphere were investigated using pyrolysis-gas chromatography/mass spectrometry and scanning electron microscopy. CO2 and light-pollution products were found to be the major products from pyrolysis volatiles; furthermore, because oxygen participates in the chemical reaction, many of the pyrolysis volatiles emitted during the paper printing process were different from those formed under an N2 atmosphere. Although a small number of the volatiles were moderately toxic products, the concentrations of these volatiles were low. Heat-induced inkless eco-printing (HIEP) was found to take less time than the pyrolysis experiment in this paper and thus resulted in fewer pyrolysis volatiles. Thus, fewer pyrolysis volatiles will be emitted within the practical temperature range; in particular, no carcinogens were emitted in the pyrolysis temperature range of 250–700 °C. Therefore, HIEP was found to be an ecologically and environmentally preferable technology.

The treatment of museum exhibits, including books and archival documents, in an atmoshpere containing a high concentration of carbon dioxide is one of the techniques using a modified atmosphere for the fumigation of objects. The efficiency of this method for pest infestation is confirmed by its commercial application. Some companies (for example, RENTOKIL) have developed stationary and portable extermination equipment. The concentration of the carbon dioxide in a gas mixture is between 58-75 per cent, the temperature during the disinfecting procedure is kept within 19-30 degrees C, and the relative humidity is kept to 70 per cent. The efficiency of this prodecure as an effective technique against microorgnisms has not been studied fully. There is evidence of both positive and negative results. Specific data on the influence of a carbon dioxide enriched atmosphere on the physical and chemical properties is limited. In theory this treatment could be dangerous for paper because of the formation of carbonic acid from carbon dioxide and water. In order to decrease the possible destructive influence of this treatment used on textile museum objects, humidity in a chamber has been kept at no more than 50 per cent. According to the data of the German conservator Binker the fumigation of a wooden altarpiece in an atmosphere of carbon dioxide did not have any adverse affect on the material or colouring of the wooden sculpture. The purpose of our research was to investigate the influence of a modified, carbon dioxide-enriched atmosphere on the properties of paper.

In their recent paper, Grandin et al. (2014) claim to have developed a novel approach, principally a ray tracing method, to analyze radio sounding data from occulted spacecraft signals by planetary atmospheres without the usual assumptions of the radio occultation inversion method of a stratified, layered, symmetric atmosphere. They apply their " new approach" to observations of the Mars Express Radio Science (MaRS) experiment and compare their resulting temperature, neutral number density and electron density profiles with those from MaRS, claiming that there is good agreement with the observations. The fact is, however, that there are serious disagreements in the most important altitude ranges. Their temperature profile shows a 30 K shift or a 300σ (1σ standard deviation = 0.1 K for the MaRS profile near the surface) difference towards warmer temperatures at the surface when compared with MaRS while the MaRS profile is in best agreement with the profile from the Mars Climate Data Base V5.0 (MCD V5.0). Their full temperature profile from the surface to 250 km altitude deviates significantly from the MCD V5.0 profile. Their ionospheric electron density profile is considerably different from that derived from the MaRs observations. Although Grandin et al. (2014) claim to derive the neutral number density and temperature profiles above 200 km, including the asymptotic exosphere temperature, it is simply not possible to derive this information from what is essentially noise.

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.

Relating to real contact area against plane smooth surface, effects of the measuring conditions on paper friction, surrounding atmosphere and applied pressure, were examined. An optical interference method using a scanning laser microscope was adopted to measure the real contact area against a plane smooth surface. The estimated contact area of paper is around 1% of nominal area for common papers. The increase in the contact area with increasing relative humidity is considered as a cause of the increase in the friction coefficient with an increase in relative humidity. The contact area of paper generally increased in a ratio of two-thirds power of the apparent pressure over a wide range of pressure. It suggested that contact of paper was generally elastic and this fact was one reason describing the decrease in the coefficient with increasing apparent pressure. However the decrease in the coefficient is little and the frictional behavior of paper can not be fully described by the contact area against a smooth surface.

Friction of commercial papers under dry, moderate and humid atmospheres was examined, comparing with those of cellulose film and aluminum foil. The friction coefficient between different papers generally gave their intermediate value. The coefficient between equal cellulosic materials including paper increased with humidity, while that of aluminum against aluminum was constant irrespective of surrounding humidity. However the surface wetting with a slight amount of water on aluminum caused rapid increase in the coefficient. The capillary force may cause this phenomenon, and the sharp increase of friction between cellulose films in humid atmosphere was similar to that observed with aluminum foils which were wetted with a slight amount of water. These suggest that the capillary force by a slight amount of water may raise frictional force of cellulosic materials including paper at high humidity.

An extensive network of gummed paper collectors was used during the 1950s for routine monitoring of radioactive fallout from weapons testing. The experiments reported in this paper were designed to examine the collection efficiency of gummed paper for wet deposition of several types of soluble and insoluble radioactive contaminants under conditions similar to those found during natural rainstorms. The collection efficiencies for each substance were determined over a range of rainfall amounts and at two separate rainfall intensities. The collection efficiency of the gummed paper is highest for large insoluble particles and lowest for soluble ionic substances. The values for 7Be and 131I ranged from about 0.30 (30%) at 2.5 mm of rain to 0.04-0.06 (4%-6%) at 20 mm of rain. These values were negatively correlated with the amount of rain and were unaffected by rain intensity. This suggests that the collection efficiency of either ion is simply a matter of rapid saturation and runoff. Neither rain amount nor rain intensity has much effect on the collection efficiency of large insoluble particles. These particles seem to settle readily onto the surface of the gummed paper from which they are not easily removed by additional rain. Analysis of the collection efficiencies of the gummed paper included the activity of both the gummed paper and the standing water on the paper. A large portion of the activity for the ionic substances was found in the standing water. There was less activity by insoluble particles in standing water. This indicates that for estimates of deposition of soluble substances, considerable bias could be introduced into the results if the standing water is discarded prior to analysis.

In the boreal forests of Alaska, recent changes in climate have influenced the exchange of trace gases, water, and energy between these forests and the atmosphere. These changes in the structure and function of boreal forests can then feed back to impact regional and global climates. In this manuscript, we examine the type and magnitude of the climate feedbacks from boreal forests in Alaska. Research generally suggests that the net effect of a warming climate is a positive regional feedback to warming. Currently, the primary positive climate feedbacks are likely related to decreases in surface albedo due to decreases in snow cover. Fewer negative feedbacks have been identified, and they may not be large enough to counterbalance the large positive feedbacks. These positive feedbacks are most pronounced at the regional scale and reduce the resilience of the boreal vegetation – climate system by amplifying the rate of regional warming. Given the recent warming in this region, the large variety of associated mechanisms that can alter terrestrial ecosystems and influence the climate system, and a reduction in the boreal forest resilience, there is a strong need to continue to quantify and evaluate the feedback pathways.

Pears (Pyrus communis `d'Anjou') were packed in six commercial paper wraps (dry; 3% oil; 3% oil with copper and ethoxyquin; 6% oil; 6% oil with ethoxyquin; 9% oil). After packing, the pears were placed in three different controlled atmosphere (CA) storage conditions in commercial CA rooms: 1) 1.5% oxygen (O) and 1% carbon dioxide (CO2); 2) 1.5% O2 and 3% CO2; 3) 1.5% O2 and 1% CO2 for 60 days, 4% O2 for 60 more days and finally 6% O2 for an additional 90 days. Pears were stored in CA for 120 and 210 days, with or without an additional 30 days in regular atmosphere (RA) storage to simulate shipping and handling. Objective quality evaluations were conducted after each storage period and sensory evaluations after 210 days of storage. Paper type influenced both the peel and flesh color of pears before and after ripening, but did not influence firmness, soluble solids or acid content. Subjective ratings of appearance and disorder incidence were unacceptable for pears stored in a variable atmosphere wrapped in dry or paper containing 3% oil. The disorder black speck was present only in pears wrapped in paper with 6% oil and stored in an atmosphere of 1.5% O2 and 1% CO2. Pears stored in an atmosphere of 1.5% O2 and 3% CO2 received acceptable subjective scores regardless of paper type.

Proton Induced X-ray Emission, PIXE is a very well established analytical method. This technique of analysis can equally be applied both in vacuum, internal PIXE, and in atmosphere, external PIXE. External PIXE has been applied to material analysis in Van de Graaff laboratory at AEOI using filters and funny filters. Advantages of using these filters have been studied when analysing ancient written documents such as envelopes, inks, and newspapers. This technique clearly demonstrated the differences between new and old inks and papers. More data is needed to show other features of this technique.

it has recently been estimated that appreciable concentrations of oxygen in the Earth’s atmosphere and oceans have only been present for the last ~10% of its ~4.5 billion year life ([4][1]). There is also increasing evidence for a “bumpy road” to atmospheric oxygenation, starting with “

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.

It has only recently been realized that solar corona can be generated by dispersions of tree pollen grains suspended in the atmosphere, and these studies have come almost exclusively from Scandinavia. Using corona photographic and surface pollen analyses, it is shown here that paper birch trees in the interior of Alaska regularly generate solar corona during the boreal green-out in mid-May. Although near-spherical in shape, these ∼27 μm average diameter particles have three surface protrusions involved in germination that are indicated to aid in the generation of elliptical corona, for which a strong preferential particle orientation is needed. For observations at solar elevation angles of ∼35°–40°, an axis ratio of about 1.2 and average radius of 2.5° (for the second-order red band) are found. Because oriented particles of a particular shape tend to fall slower than randomly oriented ones, this microdesign promotes the lateral spread of pollen and enhances tree reproductive opportunities, an especially important trait for pioneering species.

Heavy dust storms within the area of eolian morphogenesis in Eurasia and orientation of eolian mineral flows are related to formation of Asian anticyclone and its influence on atmosphere. Its centre is moving from Middle and Lower Volga, Western Kazakhstan to Altai-Sayan Mountains and Northern and Central Mongolia. Formation of cyclonic whirlwinds by its periphery determines the formation of storms, hurricanes and strong blowing dust. These processes are especially strong during early spring (March-April) when contrasts of temperatures are maximal and cyclonic activity is most intensive at the polar front. When center of anticyclone is over Central Mongolia and cyclone is over the Yellow Sea and Korea eolian processes are extremely strong; in such case there happen severe dust storms in the areas of air currents convergence over the eastern Goby, plateau Ordos, and Loess plateau.

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.

The authors describe a procedure they believe to be optimum for determining the path of a ray through an atmosphere described by a radially varying refractive index profile on the Earth. The result is exact for patched quadratic profiles inverse problem and is suitable for calculating ray paths in complex profiles. The method also facilitates greatly the inverse problem.

Information about atmospheric variables, such as presence and characteristics of supended particulates (aerosols), concentration of chemical species, humidity, temperature, etc., can be obtained remotely in an energetic-efficient manner from radiation produced by optical sources and backscattered by the atmosphere, drawing on the relatively strong interaction between electromagnetic radiation at optical wavelengths and particulates and molecules in the atmosphere. Atmospheric probing systems based on laser sources can provide information as a function of range and, being their operating principle essentially the same as that of radar (except for the fact that in atmospheric probing the target is by definiti8on the atmosphere zone illuminated by the laser, instead of a hard target), they are usually called laser radars or lidars (from Light Detection And Ranging). In addition to their ability to perform remote measurements- a characteristic that they share with other systems-lidars feature the availability of quasi-real-time data, high spatial resolution and a relative convenience to perform three-dimensional scans of the atmospheric volume under study. Basic lidar principles and capabilities are discussed in this work.

This paper is directed to individuals concerned with the effects on the atmosphere of the effluents from a paper mill. Results are presented of airborne measurements made in the plume of a Kraft process paper mill and in nearby air unaffected by the mill. Aerosol particle measurements were made using a new airborne particle sampling system which integrates the data from five instruments. Particles with equivalent diameters from 0.002 to 90 µm were measured with this facility. The concentrations of cloud condensation nuclei (CCN, aerosol particles which lead to the formation of cloud droplets) were also measured. The aerosol particle measurements show that the effluent 7 km from the paper mill investigated contains significantly higher concentrations of particles with diameters greater than 0.08 µm than nearby air unaffected by the effluent. The effluent was found to contain lower concentrations of particles smaller than 0.08 µm than nearby air, indicating that enhanced coagulation of particles may be occu...

The 13C concentration in atmospheric CO2 has been declining over the past 150 years as large quantities of 13C-depleted CO2 from fossil fuel burning are added to the atmosphere. Deforestation and other land use changes have also contributed to the trend. Looking at the 13C variations in the atmosphere and in annual growth rings of trees allows us to estimate CO2 uptake by land plants and the ocean, and assess the response of plants to climate. Here I show that the effects of the declining 13C trend in atmospheric CO2 are recorded in the isotopic composition of paper used in the printing industry, which provides a well-organized archive and integrated material derived from trees' cellulose. 13C analyses of paper from two European and two American publications showed, on average, a − 1.65 ± 1.00‰ trend between 1880 and 2000, compared with − 1.45 and − 1.57‰ for air and tree-ring analyses, respectively. The greater decrease in plant-derived 13C in the paper we tested than in the air is consistent with predicted global-scale increases in plant intrinsic water-use efficiency over the 20th century. Distinct deviations from the atmospheric trend were observed in both European and American publications immediately following the World War II period.

炭酸カリウムを保持させた東洋濾紙No.526を大気中に一定期間さらし,ここに捕集されたイオウ酸化物,二酸化窒素および塩素イオンを,イオウ酸化物についてはクロラニル酸バリウム法で,二酸化窒素はジアゾ化法で,塩素イオンはクロラニル酸水銀法で分析する方法を考案した.本法は試薬の品質が測定値に影響しないこと,気温や湿度の変化にもそれほど影響をうけないことなどの利点がある.

The evidence for predictability of interannual fluctuations in the atmosphere and oceans is reviewed. The more linear nature of tropical dynamics is contrasted with the chaotic nature of extratropical circulations. The role of the largest interannual fluctuation, the El Nino Southern Oscillation, which has its origins in the tropical Pacific, but extends to influence half the globe, is the focus of much of the review. It is argued that the statistics of the chaotic regime behaviour of the extratropics are influenced by such forcing from the tropics. Seasonal predictions can be made with empirical or physically based models. The skill of both is reviewed but most consideration is given to the latter. Such models have both atmospheric and oceanic components but there is a wide range in the complexity of these modules. Developments in both atmospheric and oceanic models, needed to improve seasonal forecasts, are discussed. It is shown that predictions are sensitive to initial conditions as well as model formulation, implying the need for ensemble integrations similar to those currently under development for medium-range weather forecasting. The benefits of developing a seasonal-climate prediction capability are considered, including connections with weather forecasting on the one hand and climate change on the other. This is not an exhaustive review of extended-range predictions. Monthly forecasting is not considered and seasonal predictability is only discussed for the tropics and northern extratropics, with some focus on Europe.

Angle-of-arrival fluctuations of a wave propagating through the atmosphere, as well as lateral fluctuations (wandering) of thin beams are phase-dependent quantities useful for sensing atmospheric turbulence, in particular for measuring structure parameter and inner and outer scale. Application to practical methods of measurement is described with some examples.

Zn pin is rubbed against Zn disk in SEM chamber and in various oxygen pressures. It is observed that the transfer particle grows larger in higher oxygen pressure. By the observation in SEM, it is clarified that the wear particle is the conversion of transfer particle. In another experimental rig, Cu pin is rubbed against Cu disk in Pt-Pd atmosphere. The size of wear particle is increased by the existence of this atmosphere. The inclusion of impurity atoms at the interface or in the transfer particle enhances the shear strength of them, which is the possible mechanism of the growth of transfer particle.

An instrument has been developed for the detection of uranium dust in the atmosphere. The principle feature of this device is its ability to indicate a gross release of alpha radiation within a few minutes of its occurrence. The unit will sound an alarm when either the indicated level or the rate of increase exceeds preset values above normal background variations. (auth)

The retention of organic solvents in solvent-treated papers has been explored using gas chromatography. Results suggest that moisture in the atmosphere will displace retained solvents completely in a few hours under an ordinary environment. A related study of the sorption of thymol vapors by paper indiCates that thymol also is not retained permanently in paper.

In the following Paper, it is proposed to illustrate more fully the hint explanatory of certain atmospheric colours, given in a notice of the remarkable red hue of condensing steam, communicated on the 21st January. Since that time, I have examined with care the principal authors who have adverted to the subject of the colour of the sky generally, and of the redness of sunset in particular; and since, in the course of that research, I have found much to confirm, and little to modify, the view which I have already taken of the subject, I hope that the present Paper may be considered as a fit appendix to my former experimental notice. It will be recollected that in it I stated the singular fact, that steam does not pass at once from the state of invisible pellucid vapour to that of a misty white cloud, such as issues from the spout of a tea-kettle; but that an intermediate stage occurs, in which it is coloured, even very highly, giving to transmitted light a hue varying from tawny yellow up to intense smoke-red. I then observed, that, since this phenomenon does not require steam of high tension for its production, it is very probable that the tints of sunset and of artificial lights seen through certain fogs, may be owing to the absorptive action of watery vapour in this critical condition.

This report details the results of an ozone exposure experiment performed on a large number of traditional natural organic colorants applied to watercolor paper with no binder. These colorants were exposed in an environmental chamber to an atmosphere containing 0.397 ± .007 parts per million (ppm) ozone at 72°F and 50% RH in the absence of light for 12 weeks. This ozone concentration is typical of that found in the Los Angeles atmosphere during a heavy smog episode. The total ozone dose delivered to the samples is equivalent to about four years of exposure to outdoor air in Los Angeles or to about eight years inside a typical air conditioned building in Los Angeles. The ozone sensitivity of these colorant systems was evaluated by monitoring the color changes which occurred during the exposure. Almost all colorant systems tested showed some degree of fading after ozone exposure, and a few of these (curcumin, dragon's blood, indigo, and madder lake) should be considered very ozone-fugitive.

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.

Russia has a huge potential for growing agricultural products. In this regard, the issue of preserving the grown crop and minimizing storage losses, which can reach 30-50%, is very relevant. Currently, there are known methods for storing agricultural crops in storage facilities with active and natural ventilation in piles, bins, containers equipped with an airing system, systems for maintaining and controlling temperature and humidity. However, these methods do not provide high safety of product laid for long-term storage. A promising direction for solving these problems is the use of the bactericidal properties of the air in contact with natural potassium salts. The Verkhnekamskoye Potassium Salt Deposit, one of the largest potash salt deposits located in Russia, contains a third of the world's reserves, which are mainly used for the production of potash fertilizers. However, the unique physical and chemical properties of natural potassium, sodium, and magnesium salts, as well as their mechanical and filtration characteristics, make it possible to significantly expand the scope of their use. In this regard, the paper describes the results of studies into the properties of the atmosphere in contact with natural potassium-magnesium salts and its effect on phytopathogens. The study of the effect of a saline-saturated atmosphere on Phytophthora infestans showed a greater dependence on the humidity of the environment and a greater degree of growth suppression in the atmosphere saturated with salt aeroions. The growth of this phytopathogen was suppressed by 39,5 % at 16% humidity, by 48,3% at 50% humidity, and by 63.1% at 85% humidity. In addition, experiments on storing potatoes in an atmosphere in contact with natural potash salts showed minimal damage to tubers by phytopathogens when using the bulk surface of potassium salt.

Systematic measurements of isotopic tracers in the atmosphere, particularly tritium, deuterium, and oxygen 18 in water vapor, are for practical reasons largely restricted to samples obtained at ground level. On the other hand, their use as atmospheric tracers requires as complete a knowledge as possible of their sources and sinks as well as of their distribution and transport patterns (in space and time) in the atmosphere. In their paper, Schell et al. [1970] attempt to develop a model that permits combination of isotope measurements in ground-level samples with meteorological parameters of the three-dimensional atmosphere in order to calculate the desired tracer distribution and transport values. In this particular case, the authors determine the tracer injection into the moist tropospheric layer (surface to 500 mb) from above.

This article reviews the information on the climatic effect of carbon dioxide and aerosols and outlines man's part in contributing to their occurence. Recent downward trends in the average surface temperature of the biosphere has lead some scientists to conclude that albedo increases due to the effect of aerosol backscatter is the causative mechanism. While there is evidence for and against this hypothesis, this paper emphasizes that albedo changes due to aerosol modification of cloud cover may be a more significant mechanism for explaining temperature trends.

The present study was done to analyze and compare synoptic conditions during the most durable pollution and clean waves (MDPW and MDCW) in Tehran City (capital of Iran). For this purpose, air quality index (AQI) data were first obtained during 2009-2019 from the Tehran Air Quality Control Company in Tehran Province. Then, a threshold of (AQI ≤ 101) representing a polluted and unhealthy atmosphere was considered as MDPW, and a threshold of (AQI ≤ 50) representing a clean (good) air was selected as MDCW in Tehran City by identifying the polluted days. The results showed the presence of MDPW during 43 polluted days from November 21, 2010 to January 2, 2011. Intensity and frequency of the polluted days during statistical period showed a decreasing trend that coincided with an increasing trend of precipitation. Analysis of synoptic conditions occurred during 43 days of MDPW indicated penetration of Siberian high-pressure from the east at sea level and extension of sub-tropical anticyclone in mid-level from the west that led to development of an anticyclone circulation with descending and converging flow in Iran and surrounding region. As a result, a calm and sustainable climate and stable concentration of pollutants were observed throughout Tehran City. Backward trajectory of sources and entry route of the polluted air to Tehran City during peak days of pollution showed that desert regions of southern Iraq and central Iran along the southern and southwestern parts played a major role in increasing concentration of pollutants during occurrence of durable wave. Different routes were observed in entry of dusty and the polluted air to Tehran City according to hybrid single-particle Lagrangian integrated trajectory (HY SPLIT) model, but in most of peak days, the areas that were near and adjacent to Tehran City with height of less than 1000 m played a greater role in particle transport. Investigation of instability indices during MDPW showed that in most days of pollution, values of instability intensity were classified into weak class and lower troposphere (1000-850 hPa) compared to higher levels, and degree of stability and calmness of the atmosphere was more. So that, the highest frequency of temperature inversions occurred near the earth's surface.

For low temperature agricultural crop and meat drying, dryers utilizing the renewable energy source (solar energy) appear to be an efficient technique as it is ecofriendly, energy efficient, and available in free of cost. This work presents the experimental investigation on a solar food dryer equipped with external reflectors to enhance the rate of drying efficiency by removing the moisture content available in the anchovy fish. A comparison of conventional open solar drying is carried out to assess the parameters such as drying efficiency, moisture removal rate, and heat energy required for drying the anchovy fish using the modified solar dryer using the natural convection technique. From the experimental results it is observed that the relative humidity greatly influence the rate of drying. The average relative humidity during the experiments using open solar drying is found as 50–65% whereas, the using solar dryer the average relative humidity inside the chamber is found as 20–35%. The relative humidity of the fish using open solar drying is higher as compared to solar dryer drying as the drying products are kept in open atmosphere. The physical examination results on the dried products proved that using a modified solar dryers, the dried product is free from insects, and dust. Also, it is found that the loss of color from the product is a minimum while compared to conventional open solar drying. The results showed that the thermal efficiency of top tray (dryer 1) and bottom tray (dryer 2) is comparatively higher as compared to that of conventional open solar drying and found as 16.73 and 19.34 %, respectively. Results also showed that nearly 20.05% of the energy could be saved using the modified solar dryer as compared to the open solar drying technique.

A simplified filter paper method of determining the 15-atmosphere percentage in soils has been tested over a range of soil textures from sands to heavy clays. The regression of filter paper determinations against pressure membrane determinations of the 15-atmosphere percentage for the 34 soils gave the equation- y = 1.03x + 3.0 (r = 0.99 and P

The Generic Screening Object hypothesis of Frank et al. (1986) is refuted, and it is indicated that the DE-1 dark pixel events do not serve as evidence for a large cometary influx. It is shown that the average scan line count profiles of the dark pixel events show no significant reductions in the two neighboring pixel positions, although at least a 9 percent reduction would be expected if the dark pixels were the result of shielding of the photometric field of view. In a reply, Frank et al. uphold their previous hypothesis, pointing out that the suggestion that the atmospheric holes are not a geophysical phenomenon is incorrect due to: (1) the use of an overly simplified model for the instrument responses to small, opaque objects as seen against a statistically fluctuating screen of dayglow intensities; and (2) an insufficient treatment of the observations.