Orthogonal design for optimization of pigment extraction from surface sediments of the Changjiang River Estuary

Using a suitable solvent for extracting pigments from sediment for high performance liquid chro-matography (HPLC) analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass, as well as community composition. Five methodolog-ical factors (sample dehydration, extraction solvent, extraction duration, number of extractions, and ratio of solvent volume: sample weight) were studied using an L₉ (3⁴) orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary (LDE), using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L₉ (3⁴) or-thogonal design experiments and showed that the extraction solvent was the most important, with extraction duration the second most important, and numbers of extraction and ratio of solvent vol-ume: sample weight was the least important. The mixed solvent treatment comprised of acetone, methanol and water (80:15:5, by volume) was best for polar pigment extraction, with 100% acetone better for apolar pigments. For most pigments employed in this study (i.e., peridinin, fucoxanthin, alloxanthin, diatoxanthin, zeaxanthin, pheophytin-a and β-carotene), 3 h was found to be enough time for extraction from these deltaic sediments. However, for chlorophyll-a, the most important pigment used for estimating algal biomass, 12 h was needed. A small amount of solvent (3 ml) with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately, no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study, taking into consideration the properties of sediments and pigments in question.     

DIRECT DETERMINATION OF STRONTIUM IN SEAWATER BY FLAME EMISSION SPECTROPHOTOMETRY

A procedure is suggested for direct determination of Sr in seawater using diluted seawater sample and background emission correction by FES. The standard deviation for 8 ppm Sr is better then 2 %, and the recovery of the added Sr is 97-105 %.     

Measurements of dissolved organic carbon (DOC) in sea water by high temperature combustion method

Dissolved organic carbon (DOC) is the largest organic carbon reservoir in sea water and plays an imporrant role in the marine carbon cycle and other biogeochemical processes in the ocean. Accurate and precise determinalion of the bOC concentration in sea water is thus a prerequisite for any interpretation of DOC biogeochemistry. A key factor in analytical quality control is an accurate determination of the blank. The assessment and distinction of DOC blanks are essential for the precise measurements of oceanic DOC. The total DOC blank includes instrument and water blanks in the high temperature catalytic oxidation (HTCO) method. DOC can be measured accurately using the HTCO method only when the instrument blank is correctly distinguished from the total DOC blank and corrected in the sample measurements. Low DOC blanks can be achieved by extensive conditioning of new catalysts and the whole instrument system, whereas instrument blanks can be quantified by subtracting the water blank from the total DOC blank. We have been able to produce low carbon nanopure water [≤2μmol/dm³(C)] and have a low instrumental blank [< 5-6 μmol/dm³(C)] when using the HTCO method. Results of concentrations and distributions of DOC in the Gulf of Mexico and the North Atlantic are oceanographically consistent. Results from DOC measurements on samples from the international DOC methods comparison program further confirmed our low values of both nenopure water and the instrument blank.     

Effect of NaNO3 Concentrations on the Growth and Fatty Acid Compositions of Nitzschia closterium and Chaetoceros gracilis

Fatty acid compositions of two strains of marine diatoms Nitzschia closterium(MACC B222)and Chaetoceros gracilis(MACCB13)have been examined.The microalgae have been grown at different initial NaNO3 concentrations(75,375,750,1125,1500,1875mg/L)and harvested at the late exponential phase.The results by one factor analysis of variance show that the NaNO3 concentrations have no significant influence on the relative growth rate of two stains of marine diatoms;the influence of NaNO3 concentrations on the fatty acids differs from species to species.The major fatty acids of two diatom strains are 14:0,16:0,16:In-7and 20:5n-3(EPA),B13 also has high percentage of 20:4n-6(6.0-9.1%).     

Anti-oxidant and anti-inflammatory activities of ultrasonicassistant extracted polyphenol-rich compounds from Sargassum muticum

Polypehnol is an important,potentially bioactive component of Sargassum muticum.In this study,ultrasonic assisted extraction of polyphenol-rich substances was performed using a 38%ethanol solution at a solid:liquid ratio of 1:30 at 68℃ for 32min,determined by single-factor and response surface methodology(RSM)optimization.The content of polyphenol was 5.66mg/g in the crude extract.Further extraction showed that the polyphenol mainly distributed in ethyl acetate(SKEE)and water phases(SKEW).The anti-oxidation test by electron spin resonance(ESR)spectrum showed that the SKEE had the strongest scavenging activity on DPPH(1,1-diphenyl-2-picrylhydrazyl)and alkyl radicals.SKEE was shown noncytotoxic but could inhibit the generation of cellular ROS,showing protective effects in H2O2 and AAPHinduced Vero cells and UV-B irradiated HaCaT cells.SKEE also signifi cantly inhibited the release of NO of LPS-induced RAW 264.7 cells.Therefore,the polyphenol-rich extracts in ethanol and ethyl acetate showed excellent anti-oxidant and anti-infl ammatory activities,which is beneficial to the development of high-value bio-substances.     

A study on sample pretreatment of analysis of Cd, Pb and Zn in seawater by IDMS

Isotope dilution mass spectrometry (IDMS) and ultra-clean room approach are successfully used in the determination of Cd, Pb and Zn in seawater and the sample pretreatment of analysis. The precision in the determination of Cd, Pb and Zn in seawater is better than±3% and the limits of detection are 6×10-12, 6×10-11 and 2.4×10-10 respectively. The effects of sample pretreatment such as filtration and acidification on the results of determination of Cd- Pb and Zn in seawater are disscussed.     

Distribution characteristics of lipids in hadal sediment in the Yap Trench

In this study,cored sediment samples collected by the Jiaolong Submersible at 6779 m depth from the hadal zone of the Yap Trench in May 2016 were sliced in 1-cm interval from top to bottom,and lipids in each sediment layer were quantitatively and qualitatively analyzed.The vertical distribution profiles of the lipids in the sediment sample,their main existing forms,and their possible sources were investigated.The results show that the concentration of lipid in the surface sediment was the highest with the carbon number from 12 to 27,dominated by medium and short-chain lipids.The total concentration of fatty acids in surface sediment was much higher than those in the offshore and deep-sea areas,being up to 325.77μg/g due to the funnel effect caused by the“V”terrain of the trench.Fatty acid 18:0 was the most abundant lipids in the sediment sample.Abnormal high concentrations of fatty acid 18:1ω7 and alkanes indicated the existence of hydrothermal fluids in the study area.In addition,saturated fatty acids and monounsaturated fatty acids existed mainly in free form,and polyunsaturated fatty acids existed mainly in bound form.Most of the alkanes were in bound form,and their major source was autochthounous input.The carbon number of alcohols in the sediment sample ranged from 12 to 20,mainly existed in bound form.The source of fatty acids was mainly autochthonous input,and the neutral lipids had both marine and terrestrial origin.This is the first study of lipids in hadal sediment of the Yap Trench.The results will promote deeper understanding of organic carbon cycle in marine environment.     

Extraction of agar from Eucheuma cottonii and Gelidium amansii seaweeds with sonication pretreatment using autoclaving method

The effect of sonication pretreatment condition on Eucheuma cottonii and Gelidium amansii seaweed towards agar extraction wae studied.Four parameters were changed during sonication to investigate the effects on agar yield and quality.These parameters include the time interval,concentration ratio,frequency,and intensity.The highest amount of agar extracted from Eucheuma cottonii species could be obtained from the time interval of 30min,seaweed weight to solvent volume ratio of 1:20,the frequency of 35Hz,and the sonication power intensity of 30%.For Gelidium amansii species,the best agar yield also could be obtained from the time interval of 30 min,1:20 of seaweed weight to water volume ratio,the frequency of 35Hz,and power intensity of 30%.From the experiment,sonication pretreatment signifi cantly influenced the yield and properties of extracted agar.The sonication with autoclaved seaweed produced agar containing less sulfate content,which is an excellent chemical property for gel electrophoresis applications.The gelstrength of sonication with autoclaving for both seaweeds,Eucheuma and Gelidium species was the highest among those by sonication with direct heating,which proved that sonication pretreatment with autoclaving could enhance the physical properties of the agar.     

Assessment of the conventional molybdenum-blue and magnesium-induced coprecipitation procedures in phosphorus measurement in various aquatic environments

Phosphorus (P) is an essential nutrient utilized by all organisms for energy transport and growth. Both the conventional molybdenum-blue method and the magnesium-induced coprecipitation (MAGIC) procedures were applied for the measurement of dissolved inorganic phosphorus (DIP) and total dissolved phosphorus (TDP) in more than 840 water samples collected between 2003 and 2005, including seawater (the Huanghai Sea, the East China Sea, and the northern South China Sea), water from rivers and estuaries (the Changjiang, the Huanghe, and the major rivers emptying into the Jiaozhou Bay), groundwater (in the drainage basin surrounding the Jiaozhou Bay), rain- water, and aquaculture water samples. The MAGIC method allows the investigation of phosphorus distributions and cycling for systems in which DIP is below the detection limits of conventional methods. Comparison between the two methods demonstrated that the concentrations obtained with both methods were signiˉcantly correlated. The di?erences of DIP and TDP concentrations measured with the two methods were higher when the concentrations of DIP and TDP were lower, implying the lower reproducibility at low concentrations. The concentration di?erences increase with the increase in the proportion of DOP in TDP, which indicates that the discrepancy of DIP concentrations measured with the two methods increases when the DOP concentration is high. The discrepancies indicated that the composition of P compounds di?ers depending on sample sources and water type; it would be useful to infer the presence of di?erent phosphorus compound pools from di?erences between the two methods. This study indicates the potential presence of a pool of alkaline-labile compounds for samples from rainwater and rivers and estuaries surrounding the Jiaozhou Bay; the potential presence of acid-labile compounds that were adsorbed by Mg(OH)2 for samples from the Changjiang Estuary, Huanghai Sea, East China Sea, and groundwater; the po- tential presence of a substantial pool of acid-labile compounds that were not adsorbed by Mg(OH)2 for samples from the Huanghe Estuary, aquaculture water, the East China Sea algal bloom water, and the northern South China Sea.     

Isolation of protein from Chlorella sorokiniana CY1 using liquid biphasic flotation assisted with sonication through sugaring-out effect

Microalgae,a sustainable source of multi beneficial components has been discovered and could be utilised in pharmaceutical,bioenergy and food applications.This study aims to investigate the sugaring-out effect on the recovery of protein from wet green microalga,Chlorella sorokiniana CY1 which was assisted with sonication.A comparison of monosaccharides and disaccharides as one of the phaseforming constituents shows that the monosaccharides,glucose was the most suitable sugar in forming the phases with acetonitrile to enhance the production of protein(52% of protein).The protein productivity of microalgae was found to be significantly influenced by the volume ratio of both phases,as the yield of protein increased to 77%.The interval time between the sonication as well as the sonication modes were influencing the protein productivity as well.The optimum protein productivity was obtained with 10s of resting time in between sonication.Pulse mode of sonication was suitable to break down the cell wall of microalgae compared to continuous mode as a lower protein yield was obtained with the application of continuous mode.The optimum condition for protein extraction were found as followed:200g/L glucose as bottom phase with volume ratio of 1:1.25,10s of resting time for ultrasonication,5s of ultrasonication in pulse mode and 0.25g of biomass weight.The high yield of protein about 81% could be obtained from microalgae which demonstrates the potential of this source and expected to play an important role in the future.     

酸化过程对不同碳酸钙含量的海洋沉积物中总氮及其同位素分析的影响

为节约成本和样品,一些学者同时分析海洋沉积物中的碳、氮及其同位素（TOC、TN、δ¹³C和δ¹⁵N）。分析沉积物中的δ¹³C,需要对样品进行酸化去除无机碳,但是这一酸化过程会使TN和δ¹⁵N的分析结果产生偏差,且偏差范围与沉积物中无机碳含量（CaCO₃）有关。本研究选取了低CaCO₃含量（1-16%）和高CaCO₃含量（20-40%）的海洋沉积物样品,比较了酸化过程对TN和δ¹⁵N的影响。研究结果表明,酸化过程对海洋沉积物中TN和δ¹⁵N的分析结果产生了显著影响。对于低CaCO₃含量的样品,酸化导致样品中TN流失了约0-40%,δ¹⁵N偏移了约0-2‰;而对于高CaCO₃含量的样品,酸化导致样品中TN流失了约10-60%,δ¹⁵N偏移了约1-14‰。表明酸化对TN和δ¹⁵N的影响已经超过了仪器的误差范围0.002%（TN）和0.08‰（δ¹⁵N）,将影响TN和δ¹⁵N的环境指示意义。因此,即使海洋沉积物样品中CaCO₃含量很低,也必须用原样分析TN和δ¹⁵N以避免酸化过程的影响。     

利用孔隙水Br/Cl、I/Cl比和氯同位素组成来示踪南海北部东沙海域浅层流体来源

The Dongsha area is one of the most promising target areas for gas hydrate exploration in the South China Sea(SCS).The study of pore water geochemistry has played a key role in Chinese gas hydrate exploration.Br/Cl,I/Cl and δ37Cl in pore water were applied here in tracing gas hydrate occurrence,chemical evolution of pore fluids and water/rock interactions in low temperature sediment environments.The samples were collected from Sites HD255 PC and HD309 PC in the Dongsha area in 2004.At Site HD255 PC,we found the elevated Br/Cl,I/Cl and decreased SO_4/Cl at the depth of 4–5 m,suggestive of a laterally migrated fluid probably generated from the gas hydrate occurrence.The range of δ37Cl is –0.54‰ to +0.96‰,and positive δ~(37)Cl at 4–5 m interval should be related with different diffusion rates between ~(35)Cl and ~(37)Cl.At Site HD309 PC,a laterally migrated fluid was also found at the depth of 3–4 m,with the Br/Cl two times to that of the seawater and decreased I/Cl,indicating the fluid has no relationship with the gas hydrate.In this site,the chlorine isotopic composition varies from –0.7‰ to+1.9‰.Extra high Br/Cl might relate with the deep generated fluid.At higher temperature and pressure,the Br/Cl of the fluid is elevated during the hydrous silicate formation,while positive δ37Cl is also associated with the same mechanism.     

Seasonal variations in the nitrogen isotopic composition of settling particles at station K2 in the western subarctic North Pacific

Intensive observations using hydrographical cruises and moored sediment trap deployments during 2010 and 2012 at station K2 in the North Pacific Western Subarctic Gyre (WSG) revealed seasonal changes in δ ¹⁵N of both suspended and settling particles. Suspended particles (SUS) were collected from depths between the surface and 200 m; settling particles by drifting sediment traps (DST; 100–200 m) and moored sediment traps (MST; 200 and 500 m). All particles showed higher δ ¹⁵N values in winter and lower in summer, contrary to the expected by isotopic fractionation during phytoplankton nitrate consumption. We suggest that these observed isotopic patterns are due to ammonium consumption via light-controlled nitrification, which could induce variations in δ ¹⁵N(SUS) of 0.4–3.1 ‰ in the euphotic zone (EZ). The δ ¹⁵N(SUS) signature was reflected by δ ¹⁵N(DST) despite modifications during biogenic transformation from suspended particles in the EZ. δ ¹⁵N enrichment (average: 3.6 ‰) and the increase in C:N ratio (by 1.6) in settling particles suggests year-round contributions of metabolites from herbivorous zooplankton as well as TEPs produced by diatoms. Accordingly, seasonal δ ¹⁵N(DST) variations of 2.4–7.0 ‰ showed a significant correlation with primary productivity (PP) at K2. By applying the observed δ ¹⁵N(DST) vs. PP regression to δ ¹⁵N(MST) of 1.9–8.0 ‰, we constructed the first annual time-series of PP changes in the WSG. This new approach to estimate productivity can be a powerful tool for further understanding of the biological pump in the WSG, even though its validity needs to be examined carefully.     

基于稳定同位素分析推定秋冬季南极半岛南极大磷虾营养变化

南极大磷虾（Euphausia superba）为南大洋生态系统中的关键种,也是南极生态系统食物网中的重要枢纽。该种秋冬季转换期的营养信息对于理解其知之甚少的越冬机制非常重要。但关于此方面的少数研究在时空变化上仍存在着差异。为此,我们调查了南极半岛秋季（4-5月）和冬季（6月）磷虾成体δ¹³C和δ¹⁵N值的个体、月份及区域性差异。我们的目标旨在检验该期间磷虾的营养变化以及磷虾与其在南极海洋生态系统中的摄食环境之间的关系。结果如下：（1）磷虾δ¹³C值与体长之间无显著关系,但δ¹⁵N值与体长之间则存在显著相关性;（2）秋季磷虾δ¹³C值呈现增长趋势,但冬初季节并无显著变化,此期间δ¹⁵N值无显著不同;（3）布兰斯菲尔德与南设得兰群岛之间的δ¹⁵N平均值显著不同。我们的数据表明南极半岛秋至初冬转换期间磷虾成体营养呈现个体、季节性及区域性变化。     

鱼耳石碳氧同位素在黄、渤海小黄鱼种群识别中的应用

Oxygen and carbon isotope ratios(δ~(18)O and δ~(13)C) in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations across the Yellow Sea and the Bohai Sea representing most of their distributional range and fisheries areas.The significant differences in the isotopic signatures showed that the five locations could be chemically distinguished and clearly separated,indicating stock subdivision.Correlation of δ~(18)O and δ~(13)C values suggested that population of L.polyactis could be divided into the Bohai Sea group,the southern Yellow Sea group and the central Yellow Sea group.Discriminant analysis of δ~(18)O and δ~(13)C values demonstrated a high significant difference with 85.7% classification accuracy.The spatial separation of L.polyactis indicated a complex stock structure across the Yellow Sea and the Bohai Sea.These results indicate that optimal fisheries management may require a comprehensive consideration on the current spatial arrangements.This study has provided further evidence that measurement of the stable isotopes ratios in otolith can be a valuable tool in the delineation of fishery management units.     

胶州湾沉积物中有机质的来源与组成及其对百年尺度环境变化的指示

The Jiaozhou Bay is characterized by heavy eutrophication that is associated with intensive anthropogenic activities. Four core sediments from the Jiaozhou Bay are analyzed using bulk technologies, including sedimentary total organic carbon(TOC), total nitrogen(TN), the stable carbon(δ~(13)C) and nitrogen(δ~(15) N) isotopic composition to obtain the comprehensive understanding of the source and composition of sedimentary organic matter and further shed light on the environmental changes of the Jiaozhou Bay on a centennial time scale.Results suggest that the TOC and TN concentrations increase in the upper core, having indicated a probable eutrophication process since the 1920 s in the inner bay and the 2000 s in the bay mouth. The TOC and TN concentrations outside the bay have also changed since 1916 owing to the variation of terrigenous input.Considering TOC/TN ratio, δ~(13) C and δ~(15) N, it can be concluded there is a mixture of terrigenous and marine organic matter sources in the study area. A simple two end-member(terrigenous and marine) mixing model usingδ~(13) C indicats that 45%–79% of TOC in the Jiaozhou Bay is from the marine source. The environmental changes of the Jiaozhou Bay are recorded by geochemical proxies, which are influenced by the intensive anthropogenic activities(e.g., extensive use of fertilizers, and discharge of sewage) and climate changes(e.g., rainfall).     

Phytoplankton production characteristics in the Eastern Atlantic and Atlantic sector of the Southern Ocean in October–November 2004

Production parameters of surface phytoplankton were measured along three transects: La Manche-Cape Town (I); Cape Town-54°S (II); 0°-49°W (along 54°S) (III). The Canary upwelling waters were most productive along transect I, where the surface chlorophyll a (Chl ₀) and the surface primary production (PP ₀) were as high as 4.3 mg/m³ and 173 mg C/m³ per day, respectively. Mosaic patterns in the distribution of these parameters were recorded in the northeastern regions of the South Subtropical Anticyclonic Gyre (Chl ₀ = 0.03–0.35 mg/m³; PP ₀ = 1.6–12.6 mg C/m³ per day). Along transect II, the average twofold southward increase in Chl ₀ (from 0.2 to 0.4 mg/m³) and the concurrent decline of the phytoplankton assimilation activity ( AN ₀) resulted in deviations from typical latitudinal changes inPP ₀. At most sites, PP ₀ values varied between 6 and 15 mg C/m³ per day. Negligible changes in Chl ₀ (0.36–0.85 mg/m³), PP ₀ (8–19 mg C/m³ per day), and AN ₀ (0.7–1.6 mg C/mg chl a per hour) were registered for the oceanic waters along transect III. Along all the transects, PP ₀ depended on Chl ₀ to a greater extent than AN ₀. The values of the latter parameter were largely determined by the water temperature and showed a slight correlation with the insolation. Along transect II, the integrated primary production (PP _int) and the layer-integrated chlorophyll a in the upper 200 m (Chl _0–200) generally varied from 180 to 360 mg C/m² per day and from 30 to 70 mg/m², respectively. In the Polar Front region, an increase in Chl _0–200, PP _int, Chl ₀, and PP ₀ up to respective values of 190 mg/m², 520 mg C/m² per day, 1.2 mg/m³, and 32 mg C/m³ per day was observed. A comparison of the water column (0–100 m) stability with the vertical distribution of the primary production and chlorophyll content along transect II implies that the thick (>100 m) upper mixed layer (UML) formed in response to the strong water cooling and wind forcing was largely responsible for the limited primary production in the Subantarctic and Antarctic regions. The large UML thickness resulted in an intense removal of plant cells from the photosynthetic layer and light starvation of a significant (up to 60%) part of the phytoplankton community.     

Geochemical characteristics of gases from the largest tight sand gas field (Sulige) and shale gas field (Fuling) in China

This study performed a detailed geochemical analyses of the components, stable carbon isotopes of alkane gas and CO₂, stable hydrogen isotopes of alkane gas and helium isotopes of reproducing gas from the largest tight gas field (Sulige) and shale gas (Fuling) field in China. The comparative study shows that tight gas from the Sulige gas field in the Ordos Basin is of coal-derived origin, which is characterized by a positive carbon and hydrogen isotopic distribution pattern (δ¹³C₁ > δ¹³C₂ > δ¹³C₃ > δ¹³C₄; δ²H₁ > δ²H₂ > δ²H₃), i.e., the carbon and hydrogen isotopes increase with increasing carbon numbers. Carbon dioxide from this field are of biogenic origin and the helium is crust-derived. Shale gas from the Fuling shale gas field belongs to oil-derived gas which has complete carbon and hydrogen isotopic reversal of secondary alteration origin (δ¹³C₁ < δ¹³C₂ < δ¹³C₃; δ²H₁ < δ²H₂ < δ²H₃), i.e., the carbon and hydrogen isotopes decrease with increasing carbon numbers. Such complete isotopic reversal distribution pattern is due to the secondary alteration like oil or gas cracking, diffusion and so on under high temperature. In that case, positive carbon or hydrogen isotopic distribution pattern will change into complete isotopic reversal as the temperature increases. Carbon dioxide is of abiogenic origin resulting from the thermal metamorphism of carbonates and helium is crust-derived.     

Retrieval of total ozone in the mesosphere with a new model of electronic-vibrational kinetics of O<Subscript>3</Subscript> and O<Subscript>2</Subscript> photolysis products

The paper presents a new model of electronic-vibrational kinetics of the products of ozone and molecular oxygen photodissociation in the terrestrial middle atmosphere. The model includes 45 excited states of the oxygen molecules O₂(b ¹, Σ _g ⁺ ,v= 0−2), O₂ (a ¹Δ _g , v= 0−5), and O₂(X ³Σ _g ⁻ , v= 1−35) and of the metastable atom O (¹ D) and over 100 aeronomic reactions. The model takes into account the dependence of quantum yields of the production of O₂(a ¹Δ _g , v= 0−5) in a singlet channel of ozone photolysis in the Hartley band on the wavelength of photolytic emission. Taking account of the electronic-vibrational kinetics is important in retrieval of the vertical profiles of ozone concentration from measured intensities of the Atm and IR Atm emissions of the oxygen bands above 65 km and leads to an increase in the ozone concentration retrieved from the 1.27-μm emission, in contrast to the previous model of pure electronic kinetics. Sensitivity analysis of the new model is made for variations in the concentrations of atmospheric constituents ([O₂], [N₂], [O(³P)], [O₃], [CO₂]), the gas temperature, rate constants of the reactions, and quantum yields of the reaction products. A group of reactions that most strongly affect the uncertainty of ozone retrieval from measured intensities of atmospheric emissions of molecular oxygen O₂(b ¹Σ _g ⁺ , v) and O₂(a ¹Δ _g , v) has been determined. Original Russian Text ? V.A. Yankovsky, V.A. Kuleshov, R.O. Manuilova, A.O. Semenov, 2007, published in Izvestiya AN. Fizika Atmosfery i Okeana, 2007, Vol. 43, No. 4, pp. 557–569.     

Estimating the parameters of pulsed sources from data on acoustic waves recorded in the atmosphere

The possibility of estimating the parameters of surface pulsed sources from data on acoustic waves recorded in the atmosphere is studied. Experimental values are given for peak pressure P ₊ of recorded acoustic signals, wave-profile area S ₊ in their positive phase, and length t ₊ of this phase, and the approximations of these parameters are obtained within wide ranges of source energy 10^–3 < E < 10¹⁰ kg TNT and scaled distances 1 < R/E ^1/3 < 4 × 10⁴ m/kg^1/3. Conventional methods of estimating the acoustic energy E according to data obtained from acoustic measurements in the atmosphere are analyzed, and ways to improve their accuracy are proposed. The influence of the type of explosions on the parameters P ₊, S ₊, and t ₊ of acoustic signals at long distances R/E ^1/3 > 500 m/kg^1/3 from explosions is shown.