It is well established that extensive depletion of ozone, initiated by heterogenous reactions on polar stratospheric clouds (PSCs) can occur in both the Arctic and Antarctic lower stratosphere. ...Moreover, it has been shown that ozone loss rates in the Arctic region in recent years reached values comparable to those over the Antarctic,. But until now the accumulated ozone losses over the Arctic have been the smaller, mainly because the period of Arctic ozone loss has not-unlike over the Antarctic-persisted well into springtime. Here we report the occurrence-during the unusually cold 1995-96 Arctic winter-of the highest recorded chemical ozone loss over the Arctic region. Two new kinds of behaviour were observed. First, ozone loss at some altitudes was observed long after the last exposure to PSCs. This continued loss appears to be due to a removal of the nitrogen species that slow down chemical ozone depletion. Second, in another altitude range ozone loss rates decreased while PSCs were still present, apparently because of an early transformation of the ozone-destroying chlorine species into less active chlorinenitrate. The balance between these two counteracting mechanisms is probably a fine one, determined by small differences in wintertime stratospheric temperatures. If the apparent cooling trend in the Arctic stratosphere is real, more dramatic ozone losses may occur in the future.
Unprecedented Arctic ozone loss in 2011 Manney, Gloria L; Santee, Michelle L; Rex, Markus ...
Nature (London),
10/2011, Volume:
478, Issue:
7370
Journal Article
Peer reviewed
Chemical ozone destruction occurs over both polar regions in local winter-spring. In the Antarctic, essentially complete removal of lower-stratospheric ozone currently results in an ozone hole every ...year, whereas in the Arctic, ozone loss is highly variable and has until now been much more limited. Here we demonstrate that chemical ozone destruction over the Arctic in early 2011 was--for the first time in the observational record--comparable to that in the Antarctic ozone hole. Unusually long-lasting cold conditions in the Arctic lower stratosphere led to persistent enhancement in ozone-destroying forms of chlorine and to unprecedented ozone loss, which exceeded 80 per cent over 18-20 kilometres altitude. Our results show that Arctic ozone holes are possible even with temperatures much milder than those in the Antarctic. We cannot at present predict when such severe Arctic ozone depletion may be matched or exceeded.
The article is devoted to the characterization of some problems of crop production and animal husbandry in the Kuzbass region (Kuzbass) during the late XIX - early XX centuries. The issues of ...livestock breeding dynamics in this territory are considered. Attention is paid to the characteristics of the structure of the Kuzbass herd in the indicated period. Based on the analysis of statistical data, the volumes of the Kuzbass herd in cabinet and state-owned villages of the Kuzbass region are presented. The question is raised about the characteristics of the agricultural districts of the Kuzbass region. The model farm of Kuzbass is being reconstructed at the time of 1913. The novelty of the study is that for the first time based on the processing of statistics, the state and dynamics of crop production and animal husbandry in the Kuzbass region (Kuzbass) in the late XIX - early XX centuries are presented. The relevance of the study is due to its scientific and social significance. The first is determined by the fact that this kind of research, based on the analysis of statistical data, is undertaken for the first time. The second is connected with the need to draw attention to the problems of sustainable socio-economic development of rural territories at present. The authors conclude that the degree of development of a particular agricultural sector in the region was determined by factors of a natural-geographical and climatic nature, as well as household needs.
The atmospheric ozone plays an important role in understanding of the processes occurring in the atmosphere and changes in the climate. Total ozone observations in Siberia were performed by Brewer ...MKIV No. 049 spectrophotometer in Tomsk, Western Siberia and SAOZ UV-Vis spectrometers deployed along the Arctic Circle in Salekhard aerological station since 1998 and Zhigansk aerological station in Eastern Siberia since 1991. We also use 2Z-ECC ozonesondes for ozone profile observations in winter-spring period at the Salekhard aerological station at the in Western Siberia and ECC-6A sondes at the drifting North Pole station NP-38 in the Central Arctic area. During the winter-spring season in 2011, Arctic ozone in the 19-21 km altitude region was observed to be more than 70% less that typical values. In the winter-spring of 2012, on the other hand, Arctic conditions were overall much warmer than in 2011, and no evidence of significant ozone loss was seen above the Asiatic regions of Russian Federation. The aim of the paper is to describe which and where these measurements were carried out and illustrate their performances by some examples of ozone data measured in Western and Eastern Siberia, Russia such as that which occurred in the winter-spring season of 2011.
Unprecedented Arctic ozone loss in 2011 Manney, Gloria L; Santee, Michelle L; Rex, Markus ...
Nature (London),
10/2011, Volume:
478, Issue:
7370
Journal Article
Peer reviewed
Chemical ozone destruction occurs over both polar regions in local winter-spring. In the Antarctic, essentially complete removal of lower-stratospheric ozone currently results in an ozone hole every ...year, whereas in the Arctic, ozone loss is highly variable and has until now been much more limited. Here we demonstrate that chemical ozone destruction over the Arctic in early 2011 was--for the first time in the observational record--comparable to that in the Antarctic ozone hole. Unusually long-lasting cold conditions in the Arctic lower stratosphere led to persistent enhancement in ozone-destroying forms of chlorine and to unprecedented ozone loss, which exceeded 80 per cent over 18-20 kilometres altitude. Our results show that Arctic ozone holes are possible even with temperatures much milder than those in the Antarctic. We cannot at present predict when such severe Arctic ozone depletion may be matched or exceeded.
Methods of evaluation of substates of sleep and sleepiness differ in, at least, two respects. Although sleepiness has not been separated from other wake and sleep substates using yes-or-no criteria ...for sleep scoring, it would be consciously perceived and, therefore, assessed with a questionary. However, such subjective method was challenged by the finding suggesting a disconnect between two most widely used subjective and objective indicators of excessive daytime sleepiness (EDS), a score on the Epworth sleepiness scale (ESS) > 10 and a reduced latency to sleep onset (SOL), respectively. We examined whether these two EDS indicators differ in their association with physiological sleepiness, i.e., the polysomnographic indexes of elevated sleep pressure. In the afternoon hours, polysomnographic recordings were obtained throughout 54 50-min and 56 90-min napping attempts of 27 and 28 university students, respectively. Within some but not all 10-min intervals of the 50- or 90-min naps, each EDS indicator was validated against different objective polysomnographic indexes suggesting an association of EDS with elevated sleep pressure. Significant differences in sleep indexes were found between participants with short and longer SOL, but they disappeared right before the appearance of such differences between participants with higher and lower ESS score (usually at the 4th 10-min interval). This mismatch in timing of appearance of significant differences might be a plausible explanation for the lack of significant association between the ESS and SOL. Therefore, the physiologic underpinnings of the ESS can be uncovered despite such a disconnect between these two EDS indicators.
Graphical abstract
This study aimed to develop a sustainable industrial chemical engineering technology to improve the interaction between technology, plants, and soil in agriculture. The signaling crosstalk between H
...2
O
2
and NO and that between H
2
O
2
and Ca
2+
influence plant developmental and physiological processes. Many promising technologies for crop stimulation and protection are based on a thorough study of the environmental impact of various physical factors. A low-temperature, high-frequency plasma was generated via cathode high-frequency glow discharge and used for the electrolysis of an aqueous solution of a low concentration of the strong electrolyte KH
2
PO
4
, with an electrolysis-activated solution named Plasmolite. The Plasmolite solution yielded a Raman (red) scattering spectrum with a maximum at 1,640 cm
−1
, which was associated with hydrogen atom vibrations, and other bands at 875, 930, 1,050, and 1,123 cm
−1
, which were associated with the aqueous electrolyte solution plasma treatment. Based on the goal of producing an optimal H
2
O
2
concentration of 100 μM, two types of seeds were exposed to a Plasmolite-based 2 × 10
–5
M KH
2
PO
4
solution moisturizing medium for three days. Approximately 92% of the spring spelled seeds (grade “Gremme”) that were exposed to this test solution sprouted, compared with 76% of the seeds exposed to a control solution. The spring rye seeds (grade “Onokhoyskaya”) that were exposed to the test solution sprouted at a rate of 90% compared with 75% in the control. The percentage of seeds that sprouted with a root length of more than 6 mm was approximately 80% for the test solution, compared to 50% for the control. Based on these results, the use of Plasmolite is considered to be promising for the production of activated H
2
O
2
for protecting plants and stimulating growth, particularly for enhancing the functions of K and P
2
O
5
of fertilizers.
An original inertial principle of solid and liquid phase separation and the construction of a slurry reactor system on this basis are investigated. A continuous operation reactor system ensures the ...presence of catalyst in the reaction mixture stays nearly constant while a minimum is withdrawn with the reaction products. The results of hydraulic tests on the developed system, consisting of reactors with volumes of 0.02 and 1.0 m3 and equipped with mechanical agitators, are discussed. The effect of agitation velocity on the velocity of slurry moving in the circulation loop, as well as the extent of withdrawal of solid particles with the clarified liquid stream leaving the reaction system, are investigated in detail. Technical characteristics of the developed reactor system for industrial‐scale Fischer‐Tropsch synthesis, hydrogenation, and other three‐phase processes are discussed.
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