Articles de revues : « Chochen »

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Mukhamedov, Yakubdjan Kadirovich. « CHOCH TRADE SYSTEM WITH CHINESE DYNASTIES AND DIPLOMATIC RELATIONS ». Frontline Social Sciences and History Journal 03, n^o 05 (1 mai 2023) : 17–25. http://dx.doi.org/10.37547/social-fsshj-03-05-02.

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The Choch oasis is one of the regions that have had trade, economic and cultural relations with the countries of the Central Asian region since ancient times. By the VI-VIII centuries, economic relations reached their peak. During this period, Choch's trade and economic relations with the Chinese dynasties and diplomatic relations took an important place. As early as the III-IV centuries AD, the Choch people had intensive trade relations with the Sughd merchants who had trade colonies in the regions of Eastern Turkestan. The common interests of the Western Turkic Khanate and the upper class of Sughd caused Sughd merchants to take a leading position in trade and economic relations in the eastern direction[21], which created the ground for Choch and Sughd people, who actively participated in these relations, to occupy the international markets of the great Silk Road trade. This article discusses choch trade system

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Marques, Flávia Charão, et Ingrid Bergman Inchausti de Barros. « Qualidade de sementes de marcela (Achyrocline satureioides) provenientes de duas populações do Rio Grande do Sul ». Ciência Rural 30, n^o 2 (avril 2000) : 241–47. http://dx.doi.org/10.1590/s0103-84782000000200008.

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Marcela é uma planta medicinal de largo uso popular, cujas propriedades despertam interesse da indústria farmacêutica. Com o objetivo de avaliar sementes de diferentes procedências e épocas de coleta, aquênios de marcela foram coletados em Eldorado do Sul e Viamão/RS, em 11 de março; 24 de março e 11 de abril. Os aquênios foram classificados em cheios, intermediários e chochos, conforme seu tamanho, coloração e rugosidade do pericarpo. A umidade foi determinada pelo método da estufa a 105ºC (± 3ºC/24h), o vigor foi avaliado pelo teste de condutividade elétrica e velocidade de germinação. A germinação foi testada a 20ºC e iluminação constante. Os lotes de 24 de março reuniram melhores características, pois aliaram maior quantidade de sementes cheias (58%), com vigor e germinação (64%) satisfatórios. Sementes de 11 de abril, embora tenham atingido maior germinação (82%), apresentaram grande quantidade de sementes chochas (49%), baixando a qualidade do lote. Em 11 de março, as sementes apresentaram significativamente maior umidade, caracterizando sua imaturidade. Os lotes coletados em Eldorado do Sul/RS apresentaram qualidade superior àqueles provenientes de Viamão/RS, evidenciando diferenças populacionais. A melhor época de coleta foi em 24 de março; a maturação das sementes parece estar relacionada à senescência da planta mãe.

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KOJIMA, Mamoru, Shun KOJIMA, Masaki SAKATA, Mio ARAI, Natsumi SASAOKA, Masashi KUME, Tetsuya YOSHIDA et Hiroyuki HAMADA. « 140 Hone-tame process in Kyo-Chochin fabrication ». Proceedings of the Materials and processing conference 2010.18 (2010) : _140–1_—_140–3_. http://dx.doi.org/10.1299/jsmemp.2010.18._140-1_.

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Pache, Matthias. « Pumé (Yaruro) and Chocoan ». Language Dynamics and Change 6, n^o 1 (2016) : 99–155. http://dx.doi.org/10.1163/22105832-00601001.

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This paper illustrates and discusses recurrent sound correspondences between Pumé (also known as Yaruro) and Chocoan languages. Pumé is a language of the Apure state of Venezuela and has so far been considered an isolate. Chocoan is a small language family of western Colombia and eastern Panama. Until now, these language groups have never been considered together and compared systematically. It is argued here that the recurrent sound correspondences attested in Chocoan and Pumé basic vocabulary are difficult to explain by coincidence or language contact. It is therefore concluded that there should be enough evidence to postulate a genealogical link between both language groups.

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Chan Miller, Christopher, Daniel J. Jacob, Eloise A. Marais, Karen Yu, Katherine R. Travis, Patrick S. Kim, Jenny A. Fisher et al. « Glyoxal yield from isoprene oxidation and relation to formaldehyde : chemical mechanism, constraints from SENEX aircraft observations, and interpretation of OMI satellite data ». Atmospheric Chemistry and Physics 17, n^o 14 (18 juillet 2017) : 8725–38. http://dx.doi.org/10.5194/acp-17-8725-2017.

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Abstract. Glyoxal (CHOCHO) is produced in the atmosphere by the oxidation of volatile organic compounds (VOCs). Like formaldehyde (HCHO), another VOC oxidation product, it is measurable from space by solar backscatter. Isoprene emitted by vegetation is the dominant source of CHOCHO and HCHO in most of the world. We use aircraft observations of CHOCHO and HCHO from the SENEX campaign over the southeast US in summer 2013 to better understand the CHOCHO time-dependent yield from isoprene oxidation, its dependence on nitrogen oxides (NOx ≡ NO + NO2), the behavior of the CHOCHO–HCHO relationship, the quality of OMI CHOCHO satellite observations, and the implications for using CHOCHO observations from space as constraints on isoprene emissions. We simulate the SENEX and OMI observations with the Goddard Earth Observing System chemical transport model (GEOS-Chem) featuring a new chemical mechanism for CHOCHO formation from isoprene. The mechanism includes prompt CHOCHO formation under low-NOx conditions following the isomerization of the isoprene peroxy radical (ISOPO2). The SENEX observations provide support for this prompt CHOCHO formation pathway, and are generally consistent with the GEOS-Chem mechanism. Boundary layer CHOCHO and HCHO are strongly correlated in the observations and the model, with some departure under low-NOx conditions due to prompt CHOCHO formation. SENEX vertical profiles indicate a free-tropospheric CHOCHO background that is absent from the model. The OMI CHOCHO data provide some support for this free-tropospheric background and show southeast US enhancements consistent with the isoprene source but a factor of 2 too low. Part of this OMI bias is due to excessive surface reflectivities assumed in the retrieval. The OMI CHOCHO and HCHO seasonal data over the southeast US are tightly correlated and provide redundant proxies of isoprene emissions. Higher temporal resolution in future geostationary satellite observations may enable detection of the prompt CHOCHO production under low-NOx conditions apparent in the SENEX data.

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Ruiz-Santillán, María, Emiliana Huamán et Freddy Mejía. « ECOLOGICAL DIAGNOSIS OF HUMEDAL CHOCHOC ». REBIOL 39, n^o 2 (31 décembre 2019) : 3–18. http://dx.doi.org/10.17268/rebiol.2019.39.02.01.

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Myriokefalitakis, S., M. Vrekoussis, K. Tsigaridis, F. Wittrock, A. Richter, C. Brühl, R. Volkamer, J. P. Burrows et M. Kanakidou. « The influence of natural and anthropogenic secondary sources on the glyoxal global distribution ». Atmospheric Chemistry and Physics 8, n^o 16 (28 août 2008) : 4965–81. http://dx.doi.org/10.5194/acp-8-4965-2008.

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Abstract. Glyoxal, the smallest dicarbonyl, which has recently been observed from space, is expected to provide indications on volatile organic compounds (VOC) oxidation and secondary aerosol formation in the troposphere. Glyoxal (CHOCHO) is known to be mostly of natural origin and is produced during biogenic VOC oxidation. However, a number of anthropogenically emitted hydrocarbons, like acetylene and aromatics, have been positively identified as CHOCHO precursors. The present study investigates the contribution of pollution to the CHOCHO levels by taking into account the secondary chemical formation of CHOCHO from precursors emitted from biogenic, anthropogenic and biomass burning sources. The impact of potential primary land emissions of CHOCHO is also investigated. A global 3-dimensional chemistry transport model of the troposphere (TM4-ECPL) able to simulate the gas phase chemistry coupled with all major aerosol components is used. The secondary anthropogenic contribution from fossil fuel and industrial VOCs emissions oxidation to the CHOCHO columns is found to reach 20–70% in the industrialized areas of the Northern Hemisphere and 3–20% in the tropics. This secondary CHOCHO source is on average three times larger than that from oxidation of VOCs from biomass burning sources. The chemical production of CHOCHO is calculated to equal to about 56 Tg y−1 with 70% being produced from biogenic hydrocarbons oxidation, 17% from acetylene, 11% from aromatic chemistry and 2% from ethene and propene. CHOCHO is destroyed in the troposphere primarily by reaction with OH radicals (23%) and by photolysis (63%), but it is also removed from the atmosphere through wet (8%) and dry deposition (6%). Potential formation of secondary organic aerosol through CHOCHO losses on/in aerosols and clouds is neglected here due to the significant uncertainties associated with the underlying chemistry. The global annual mean CHOCHO burden and lifetime in the model domain are estimated to be 0.02 Tg (equal to the global burden seen by SCIAMACHY over land for the year 2005) and about 3 h, respectively. The model results are compared with satellite observations of CHOCHO columns. When accounting only for the secondary sources of CHOCHO in the model, the model underestimates CHOCHO columns observed by satellites. This is attributed to an overestimate of CHOCHO sinks or a missing global source of about 20 Tg y−1. Using the current primary emissions of CHOCHO from biomass burning together with the anthropogenic combustion sources of about 7 Tg y−1 leads to an overestimate by the model over hot spot areas.

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Sinreich, R., R. Volkamer, F. Filsinger, U. Frieß, C. Kern, U. Platt, O. Sebastián et T. Wagner. « MAX-DOAS detection of glyoxal during ICARTT 2004 ». Atmospheric Chemistry and Physics Discussions 6, n^o 5 (26 septembre 2006) : 9459–81. http://dx.doi.org/10.5194/acpd-6-9459-2006.

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Abstract. The direct detection of glyoxal (CHOCHO), the smallest α-dicarbonyl, in the open atmosphere by active differential optical absorption spectroscopy (DOAS) has recently been demonstrated (Volkamer et al., 2005a) and triggered the very recent successful detection of CHOCHO from space (Kurosu et al., 2005; Wittrock et al., 2006; Beirle et al., 2006). Here we report the first detection of CHOCHO by passive multi axis differential optical absorption spectroscopy (MAX-DOAS). CHOCHO and NO2 slant column measurements were conducted at MIT, Cambridge, USA, and on board the research vessel Ron Brown in the Gulf of Maine as part of the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) 2004 campaign. For a day with nearly clear sky conditions, radiative transfer modeling was employed to derive diurnal CHOCHO mixing ratios for both sites. CHOCHO mixing ratios at MIT varied from 40 to 120 ppt, with peak values observed around noon. Mixing ratios over the Gulf of Maine were found to be up to 3 times larger than at MIT. The CHOCHO-to-NO2ratio at MIT was <0.03, and enhancements of this ratio by up to two orders of magnitude were found over the Gulf of Maine. This paper focuses on the instrumental aspects involved with MAX-DOAS measurements of CHOCHO.

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Alvarado, Leonardo M. A., Andreas Richter, Mihalis Vrekoussis, Andreas Hilboll, Anna B. Kalisz Hedegaard, Oliver Schneising et John P. Burrows. « Unexpected long-range transport of glyoxal and formaldehyde observed from the Copernicus Sentinel-5 Precursor satellite during the 2018 Canadian wildfires ». Atmospheric Chemistry and Physics 20, n^o 4 (25 février 2020) : 2057–72. http://dx.doi.org/10.5194/acp-20-2057-2020.

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Abstract. Glyoxal (CHOCHO) and formaldehyde (HCHO) are intermediate products in the tropospheric oxidation of the majority of volatile organic compounds (VOCs). CHOCHO is also a precursor of secondary organic aerosol (SOA) in the atmosphere. CHOCHO and HCHO are released from biogenic, anthropogenic, and pyrogenic sources. CHOCHO and HCHO tropospheric lifetimes are typically considered to be short during the daytime at mid-latitudes (e.g. several hours), as they are rapidly removed from the atmosphere by their photolysis, oxidation by OH, and uptake on particles or deposition. At night and at high latitudes, tropospheric lifetimes increase to many hours or even days. Previous studies demonstrated that CHOCHO and HCHO vertical column densities (VCDs) are well retrieved from space-borne observations using differential optical absorption spectroscopy (DOAS). In this study, we present CHOCHO and HCHO VCDs retrieved from measurements by TROPOMI (TROPOspheric Monitoring Instrument), launched on the Sentinel-5 Precursor (S5P) platform in October 2017. We observe strongly elevated amounts of CHOCHO and HCHO during the 2018 fire season in British Columbia, Canada, where a large number of fires occurred in August. CHOCHO and HCHO plumes from individual fire hot spots are observed in air masses travelling over distances of up to 1500 km, i.e. much longer than expected for the relatively short tropospheric lifetime expected for CHOCHO and HCHO. Comparison with simulations by the particle dispersion model FLEXPART (FLEXible PARTicle dispersion model) indicates that effective lifetimes of 20 h and more are needed to explain the observations of CHOCHO and HCHO if they decay in an effective first-order process. FLEXPART used in the study calculates accurately the transport. In addition an exponential decay, in our case assumed to be photochemical, of a species along the trajectory is added. We have used this simple approach to test our assumption that CHOCHO and HCHO are created in the fires and then decay at a constant rate in the plume as it is transported. This is clearly not the case and we infer that CHOCHO and HCHO are either efficiently recycled during transport or continuously formed from the oxidation of longer-lived precursors present in the plume, or possibly a mixture of both. We consider the best explanation of the observed CHOCHO and HCHO VCD in the plumes of the fire is that they are produced by oxidation of longer-lived precursors, which were also released by the fire and present in the plume.

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Tan, M. Erwin S. H. « Reply to Chocron and Kaili ». European Journal of Cardio-Thoracic Surgery 37, n^o 4 (avril 2010) : 980–81. http://dx.doi.org/10.1016/j.ejcts.2009.11.013.

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Kim, Dongwook, Changmin Cho, Seokhan Jeong, Soojin Lee, Benjamin A. Nault, Pedro Campuzano-Jost, Douglas A. Day et al. « Field observational constraints on the controllers in glyoxal (CHOCHO) reactive uptake to aerosol ». Atmospheric Chemistry and Physics 22, n^o 2 (18 janvier 2022) : 805–21. http://dx.doi.org/10.5194/acp-22-805-2022.

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Abstract. Glyoxal (CHOCHO), the simplest dicarbonyl in the troposphere, is a potential precursor for secondary organic aerosol (SOA) and brown carbon (BrC) affecting air quality and climate. The airborne measurement of CHOCHO concentrations during the KORUS-AQ (KORea–US Air Quality study) campaign in 2016 enables detailed quantification of loss mechanisms pertaining to SOA formation in the real atmosphere. The production of this molecule was mainly from oxidation of aromatics (59 %) initiated by hydroxyl radical (OH). CHOCHO loss to aerosol was found to be the most important removal path (69 %) and contributed to roughly ∼ 20 % (3.7 µg sm−3 ppmv−1 h−1, normalized with excess CO) of SOA growth in the first 6 h in Seoul Metropolitan Area. A reactive uptake coefficient (γ) of ∼ 0.008 best represents the loss of CHOCHO by surface uptake during the campaign. To our knowledge, we show the first field observation of aerosol surface-area-dependent (Asurf) CHOCHO uptake, which diverges from the simple surface uptake assumption as Asurf increases in ambient condition. Specifically, under the low (high) aerosol loading, the CHOCHO effective uptake rate coefficient, keff,uptake, linearly increases (levels off) with Asurf; thus, the irreversible surface uptake is a reasonable (unreasonable) approximation for simulating CHOCHO loss to aerosol. Dependence on photochemical impact and changes in the chemical and physical aerosol properties “free water”, as well as aerosol viscosity, are discussed as other possible factors influencing CHOCHO uptake rate. Our inferred Henry's law coefficient of CHOCHO, 7.0×108 M atm−1, is ∼ 2 orders of magnitude higher than those estimated from salting-in effects constrained by inorganic salts only consistent with laboratory findings that show similar high partitioning into water-soluble organics, which urges more understanding on CHOCHO solubility under real atmospheric conditions.

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Sinreich, R., R. Volkamer, F. Filsinger, U. Frieß, C. Kern, U. Platt, O. Sebastián et T. Wagner. « MAX-DOAS detection of glyoxal during ICARTT 2004 ». Atmospheric Chemistry and Physics 7, n^o 5 (22 février 2007) : 1293–303. http://dx.doi.org/10.5194/acp-7-1293-2007.

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Abstract. The direct detection of glyoxal (CHOCHO), the smallest α-dicarbonyl, in the open atmosphere by active differential optical absorption spectroscopy (DOAS) has recently been demonstrated (Volkamer et al., 2005a) and triggered the very recent successful detection of CHOCHO from space (Kurosu et al., 2005; Wittrock et al., 2006; Beirle et al., 2006). Here we report the first comprehensive analysis of CHOCHO by passive multi axis differential optical absorption spectroscopy (MAX-DOAS). CHOCHO and NO2 slant column measurements were conducted at the Massachusetts Institute of Technology (MIT), Cambridge, USA, and on board the research vessel Ron Brown in the Gulf of Maine as part of the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) 2004 campaign. For a day with nearly clear sky conditions, radiative transfer modeling was employed to derive diurnal CHOCHO mixing ratios in the planetary boundary layer (PBL) for both sites. CHOCHO mixing ratios at MIT varied from 40 to 140 ppt, with peak values observed around noon. Mixing ratios over the Gulf of Maine were found to be up to 2.5 times larger than at MIT. The CHOCHO-to-NO2 ratio at MIT was <0.03, and enhancements of this ratio by up to two orders of magnitude were found over the Gulf of Maine. This paper focuses on the methodological aspects involved with MAX-DOAS measurements of CHOCHO.

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Li, X., F. Rohrer, T. Brauers, A. Hofzumahaus, K. Lu, M. Shao, Y. H. Zhang et A. Wahner. « Modeling of HCHO and CHOCHO at a semi-rural site in southern China during the PRIDE-PRD2006 campaign ». Atmospheric Chemistry and Physics 14, n^o 22 (21 novembre 2014) : 12291–305. http://dx.doi.org/10.5194/acp-14-12291-2014.

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Abstract. HCHO and CHOCHO are important trace gases in the atmosphere, serving as tracers of VOC oxidations. In the past decade, high concentrations of HCHO and CHOCHO have been observed for the Pearl River Delta (PRD) region in southern China. In this study, we performed box model simulations of HCHO and CHOCHO at a semi-rural site in the PRD, focusing on understanding their sources and sinks and factors influencing the CHOCHO to HCHO ratio (RGF). The model was constrained by the simultaneous measurements of trace gases and radicals. Isoprene oxidation by OH radicals is the major pathway forming HCHO, followed by degradations of alkenes, aromatics, and alkanes. The production of CHOCHO is dominated by isoprene and aromatic degradation; contributions from other NMHCs are of minor importance. Compared to the measurement results, the model predicts significant higher HCHO and CHOCHO concentrations. Sensitivity studies suggest that fresh emissions of precursor VOCs, uptake of HCHO and CHOCHO by aerosols, fast vertical transport, and uncertainties in the treatment of dry deposition all have the potential to contribute significantly to this discrepancy. Our study indicates that, in addition to chemical considerations (i.e., VOC composition, OH and NOx levels), atmospheric physical processes (e.g., transport, dilution, deposition) make it difficult to use the CHOCHO to HCHO ratio as an indicator for the origin of air mass composition.

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Li, X., F. Rohrer, T. Brauers, A. Hofzumahaus, K. Lu, M. Shao, Y. H. Zhang et A. Wahner. « Modeling of HCHO and CHOCHO at a semi-rural site in southern China during the PRIDE-PRD2006 campaign ». Atmospheric Chemistry and Physics Discussions 13, n^o 12 (17 décembre 2013) : 33013–54. http://dx.doi.org/10.5194/acpd-13-33013-2013.

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Abstract. HCHO and CHOCHO are important trace gases in the atmosphere, serving as tracers of VOCs oxidations. In the past decade, high concentrations of HCHO and CHOCHO have been observed for the Pearl River Delta (PRD) region in southern China. In this study, we performed box model simulations of HCHO and CHOCHO at a semi-rural site in PRD, focusing on understanding their sources and sinks and factors influencing the CHOCHO to HCHO ratio (RGF). The model was constrained by the simultaneous measurements of trace gases and radicals. Isoprene oxidation by OH radicals is the major pathway forming HCHO, followed by degradations of alkenes, aromatics, and alkanes. The production of CHOCHO is dominated by isoprene and aromatic degradation; contributions from other NMHCs are of minor importance. The modeled RGF shows a complex dependence on the VOCs composition, OH and NOx levels, and atmospheric physical processes, which suggest the necessity of careful treatment of RGF as an indicator of anthropogenic or biogenic emissions. Compared to the measurement results, the model predicts significant higher HCHO and CHOCHO concentrations. Sensitivity studies suggest that this discrepancy is to a large extent (>70%) due to the missing consideration of fresh emissions, vertical transport of precursor VOCs, and uptake of HCHO and CHOCHO by aerosols in the model. Insufficient treatments of dry deposition of HCHO and CHOCHO and of vertical dilution of all species in the model account for the rest 30% discrepancy. Our study indicates that, in addition to chemical mechanisms, atmospheric physical processes (e.g., transport, dilution, deposition) have to be well considered for a box model predicting HCHO and CHOCHO concentrations.

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Sinreich, R., S. Coburn, B. Dix et R. Volkamer. « Ship-based detection of glyoxal over the remote tropical Pacific Ocean ». Atmospheric Chemistry and Physics Discussions 10, n^o 6 (21 juin 2010) : 15075–107. http://dx.doi.org/10.5194/acpd-10-15075-2010.

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Abstract. We present the first detection of glyoxal (CHOCHO) over the remote tropical Pacific Ocean in the Marine Boundary Layer (MBL). The measurements were conducted by means of the University of Colorado Ship Multi-Axis Differential Optical Spectroscopy (CU SMAX-DOAS) instrument aboard the research vessel Ronald H. Brown. The research vessel was on a cruise in the framework of the VAMOS Ocean-Cloud-Atmosphere-Land Study – Regional Experiment (VOCALS-REx) and the Tropical Atmosphere Ocean (TAO) projects lasting from October 2008 through January 2009 (74 days at sea). The CU SMAX-DOAS instrument features a motion compensation system to characterize the pitch and roll of the ship and to compensate for ship movements in real time. We found elevated mixing ratios of up to 170 ppt CHOCHO located inside the MBL up to 3000 km from the continental coast over biologically active upwelling regions of the tropical Eastern Pacific Ocean. This is surprising since CHOCHO is very short lived (atmospheric life time ~2 h) and highly water soluble (Henry's Law constant H=4.2×105 M/atm). This CHOCHO cannot be explained by transport of it or its precursors from continental sources. Rather, the open ocean is a source for CHOCHO to the atmosphere. Dissolved Organic Matter (DOM) photochemistry in surface waters is a source for Volatile Organic Compounds (VOCs) to the atmosphere, e.g. acetaldehyde. The extension of this mechanism to very soluble gases, like CHOCHO, is not straightforward since the air-sea flux is directed from the atmosphere into the ocean. For CHOCHO, the dissolved concentrations would need to be extremely high in order to explain our gas-phase observations by this mechanism (40–70 μM CHOCHO, compared to ~0.01 μM acetaldehyde and 60–70 μM DOM). Further, while there is as yet no direct measurement of VOCs in our study area, measurements of the CHOCHO precursors isoprene, and/or acetylene over phytoplankton bloom areas in other parts of the oceans are too low (by a factor of 10–100) to explain the observed CHOCHO amounts. We conclude that our CHOCHO data cannot be explained by currently understood processes. Yet, it supports first global source estimates of 20 Tg/year CHOCHO from the oceans, which likely is a significant source of secondary organic aerosol (SOA). This chemistry is currently not considered by atmospheric models.

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Sinreich, R., S. Coburn, B. Dix et R. Volkamer. « Ship-based detection of glyoxal over the remote tropical Pacific Ocean ». Atmospheric Chemistry and Physics 10, n^o 23 (1 décembre 2010) : 11359–71. http://dx.doi.org/10.5194/acp-10-11359-2010.

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Abstract. We present the first detection of glyoxal (CHOCHO) over the remote tropical Pacific Ocean in the Marine Boundary Layer (MBL). The measurements were conducted by means of the University of Colorado Ship Multi-Axis Differential Optical Absorption Spectroscopy (CU SMAX-DOAS) instrument aboard the research vessel Ronald H. Brown. The research vessel was on a cruise in the framework of the VAMOS Ocean-Cloud-Atmosphere-Land Study – Regional Experiment (VOCALS-REx) and the Tropical Atmosphere Ocean (TAO) projects lasting from October 2008 through January 2009 (74 days at sea). The CU SMAX-DOAS instrument features a motion compensation system to characterize the pitch and roll of the ship and to compensate for ship movements in real time. We found elevated mixing ratios of up to 140 ppt CHOCHO located inside the MBL up to 3000 km from the continental coast over biologically active upwelling regions of the tropical Eastern Pacific Ocean. This is surprising since CHOCHO is very short lived (atmospheric life time ~2 h) and highly water soluble (Henry's Law constant H = 4.2 × 105 M/atm). This CHOCHO cannot be explained by transport of it or its precursors from continental sources. Rather, the open ocean must be a source for CHOCHO to the atmosphere. Dissolved Organic Matter (DOM) photochemistry in surface waters is a source for Volatile Organic Compounds (VOCs) to the atmosphere, e.g. acetaldehyde. The extension of this mechanism to very soluble gases, like CHOCHO, is not straightforward since the air-sea flux is directed from the atmosphere into the ocean. For CHOCHO, the dissolved concentrations would need to be extremely high in order to explain our gas-phase observations by this mechanism (40–70 μM CHOCHO, compared to ~0.01 μM acetaldehyde and 60–70 μM DOM). Further, while there is as yet no direct measurement of VOCs in our study area, measurements of the CHOCHO precursors isoprene, and/or acetylene over phytoplankton bloom areas in other parts of the oceans are too low (by a factor of 10–100) to explain the observed CHOCHO amounts. We conclude that our CHOCHO data cannot be explained by currently understood processes. Yet, it supports first global source estimates of 20 Tg/year CHOCHO from the oceans, which likely is a significant source of secondary organic aerosol (SOA). This chemistry is currently not considered by atmospheric models.

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Javed, Zeeshan, Cheng Liu, Muhammad Khokhar, Wei Tan, Haoran Liu, Chengzhi Xing, Xiangguang Ji et al. « Ground-Based MAX-DOAS Observations of CHOCHO and HCHO in Beijing and Baoding, China ». Remote Sensing 11, n^o 13 (27 juin 2019) : 1524. http://dx.doi.org/10.3390/rs11131524.

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Glyoxal (CHOCHO) and formaldehyde (HCHO) trace gases were successfully retrieved from a multi-axis differential optical absorption spectroscopy (MAX-DOAS) system in Beijing (39.95°N, 116.32°E) and Baoding (39.15°N, 115.40°E), China. The measurements of these trace gases span the period from May 2017 to April 2018. Higher levels of trace gases were observed in Beijing most likely due to increased transport and industrial activities compared to Baoding. Different time scales were analyzed from seasonal to daily levels. Seasonal variation categorized by wintertime maximum and summertime minimum was observed for CHOCHO, while for HCHO maximum values were recorded during summer at both observation points. Variations in the diurnal cycle of trace gases were examined. The results are consistent with strong links to photo-oxidations of VOCs for HCHO production, whereas the CHOCHO diurnal variation can be related to anthropogenic effects in the evening. Weekends didn’t have any significant effect on both HCHO and CHOCHO. We investigated the temperature dependency of HCHO and CHOCHO. HCHO shows positive correlation with air temperature, which strengthened the argument that HCHO production is linked to photo-oxidation of VOCs. CHOCHO is anti-correlated with air temperature. This suggests that photolysis is a major sink for CHOCHO in Beijing and Baoding. We also investigated the relationship between CHOCHO and HCHO VCDs with enhanced vegetation index (EVI) data obtained from MODIS, which represents a direct relation with biogenic emissions. The positive correlations were observed among monthly mean HCHO VCDs and monthly mean EVI at both monitoring stations. The strong correlation of HCHO with EVI found, suggests that oxidation of isoprene and HCHO production is strongly related, while negative correlation was observed among CHOCHO VCDs and EVI.

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Kiverin, Alexey D., et Ivan S. Yakovenko. « Estimation of critical conditions for deflagration-to-detonation transition in obstructed channels filled with gaseous mixtures ». Mathematical Modelling of Natural Phenomena 13, n^o 6 (2018) : 54. http://dx.doi.org/10.1051/mmnp/2018071.

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The paper considers the peculiarities of deflagration-to-detonation transition (DDT) in obstructed channels filled with gaseous mixtures. The necessary stage in flame evolution prior to DDT is the stage of flame propagation in so-called “chocked flame” regime. The structure of the chocked flame is studied numerically in details that allows formulating the criterion of its stability. In turn, the stability of chocked flame determines the possibility of further flame acceleration and subsequent DDT. Such a criterion is of purely chemical nature and can be estimated using the parametric study involving simple one-dimensional calculations. It should be however noted that to get the prediction of DDT in real complex geometry one should additionally estimate the particular conditions of chocked flame formation in the given geometry. Moreover, the particular mechanisms of detonation onset should be analyzed. Such a complex analysis involving both chemical criterion and analysis of geometrical conditions is applied to the estimation of DDT possibility in obstructed channels. The obtained results are in a good agreement with available experimental data.

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Chan Miller, Christopher, Daniel J. Jacob, Gonzalo González Abad et Kelly Chance. « Hotspot of glyoxal over the Pearl River delta seen from the OMI satellite instrument : implications for emissions of aromatic hydrocarbons ». Atmospheric Chemistry and Physics 16, n^o 7 (13 avril 2016) : 4631–39. http://dx.doi.org/10.5194/acp-16-4631-2016.

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Abstract. The Pearl River delta (PRD) is a densely populated hub of industrial activity located in southern China. OMI (Ozone Monitoring Instrument) satellite observations reveal a large hotspot of glyoxal (CHOCHO) over the PRD that is almost twice as large as any other in Asia. Formaldehyde (HCHO) and NO2 observed by OMI are also high in the PRD but no more than in other urban/industrial areas of China. The CHOCHO hotspot over the PRD can be explained by industrial paint and solvent emissions of aromatic volatile organic compounds (VOCs), with toluene being a dominant contributor. By contrast, HCHO in the PRD originates mostly from VOCs emitted by combustion (principally vehicles). By applying a plume transport model to wind-segregated OMI data, we show that the CHOCHO and HCHO enhancements over the PRD observed by OMI are consistent with current VOC emission inventories. Prior work using CHOCHO retrievals from the SCIAMACHY satellite instrument suggested that emission inventories for aromatic VOCs in the PRD were too low by a factor of 10–20; we attribute this result in part to bias in the SCIAMACHY data and in part to underestimated CHOCHO yields from oxidation of aromatics. Our work points to the importance of better understanding CHOCHO yields from the oxidation of aromatics in order to interpret space-based CHOCHO observations in polluted environments.

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García-Borrás, F. J. « Cuando los mundos chocan ». Revista Eureka sobre enseñanza y divulgación de las ciencias 3, n^o 2 (2006) : 268–86. http://dx.doi.org/10.25267/rev_eureka_ensen_divulg_cienc.2006.v3.i2.08.

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Alvarado, L. M. A., A. Richter, M. Vrekoussis, F. Wittrock, A. Hilboll, S. F. Schreier et J. P. Burrows. « An improved glyoxal retrieval from OMI measurements ». Atmospheric Measurement Techniques Discussions 7, n^o 6 (5 juin 2014) : 5559–99. http://dx.doi.org/10.5194/amtd-7-5559-2014.

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Abstract. Satellite observations from the SCIAMACHY, GOME-2, and OMI spectrometers have been used to retrieve atmospheric columns of glyoxal (CHOCHO) with the DOAS method. High CHOCHO levels are found over regions with large biogenic and pyrogenic emissions, and hot-spots have been identified over areas of anthropogenic activities. This study focuses on the development of an improved retrieval for CHOCHO from measurements by the OMI instrument. From sensitivity tests, an optimal fitting window and polynomial degree are determined. Two different approaches to reduce the interference of liquid water absorption over oceanic regions are evaluated, achieving significant reduction of negative columns over clear water regions. Moreover, a high temperature absorption cross-section of nitrogen dioxide (NO2) is introduced in the DOAS retrieval to account for potential interferences of NO2 over regions with large anthropogenic emissions, leading to improved fit quality over these areas. A comparison with vertical CHOCHO columns retrieved from measurements of the GOME-2 and SCIAMACHY instruments over continental regions is performed, showing overall good consistency. Using the new OMI CHOCHO data set, the link between fires and glyoxal columns is investigated for two selected regions in Africa. In addition, mapped averages are computed for a fire event in the east of Moscow between mid-July and mid-August 2010. In both cases, enhanced CHOCHO levels are found in close spatial and temporal proximity to MODIS fire radiative power, demonstrating that pyrogenic emissions can be clearly identified in the OMI CHOCHO product.

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Javed, Zeeshan, Cheng Liu, Kalim Ullah, Wei Tan, Chengzhi Xing et Haoran Liu. « Investigating the Effect of Different Meteorological Conditions on MAX-DOAS Observations of NO2 and CHOCHO in Hefei, China ». Atmosphere 10, n^o 7 (27 juin 2019) : 353. http://dx.doi.org/10.3390/atmos10070353.

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In this work, a ground-based remote sensing instrument was used for observation of the trace gases NO2 and CHOCHO in Hefei, China. Excessive development and rapid economic growth over the years have resulted in the compromising of air quality in this city, with haze being the most prominent environmental problem. This is first study covering observation of CHOCHO in Hefei (31.783° N, 117.201° E). The observation period of this study, i.e., July 2018 to December 2018, is divided into three different categories: (1) clear days, (2) haze days, and (3) severe haze days. The quality of the differential optical absorption spectroscopy (DOAS) fit for both CHOCHO and NO2 was low during severe haze days due to a reduced signal to noise ratio. NO2 and CHOCHO showed positive correlations with PM2.5, producing R values of 0.95 and 0.98, respectively. NO2 showed strong negative correlations with visibility and air temperature, obtaining R values of 0.97 and 0.98, respectively. CHOCHO also exhibited strong negative correlations with temperature and visibility, displaying R values of 0.83 and 0.91, respectively. The average concentration of NO2, CHOCHO, and PM2.5 during haze days was larger compared to that of clear days. Diurnal variation of both CHOCHO and NO2 showed a significant decreasing trend in the afternoons during clear days due to photolysis, while during haze days these two gases started to accumulate as their residence time increases in the absence of photolysis. There was no prominent weekly cycle for both trace gases.

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Alvarado, L. M. A., A. Richter, M. Vrekoussis, F. Wittrock, A. Hilboll, S. F. Schreier et J. P. Burrows. « An improved glyoxal retrieval from OMI measurements ». Atmospheric Measurement Techniques 7, n^o 12 (3 décembre 2014) : 4133–50. http://dx.doi.org/10.5194/amt-7-4133-2014.

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Abstract. Satellite observations from the SCIAMACHY, GOME-2 and OMI spectrometers have been used to retrieve atmospheric columns of glyoxal (CHOCHO) with the DOAS method. High CHOCHO levels were found over regions with large biogenic and pyrogenic emissions, and hot-spots have been identified over areas of anthropogenic activities. This study focuses on the development of an improved retrieval for CHOCHO from measurements by the OMI instrument. From sensitivity tests, a fitting window and a polynomial degree are determined. Two different approaches to reduce the interference of liquid water absorption over oceanic regions are evaluated, achieving significant reduction of the number of negative columns over clear water regions. The impact of using different absorption cross-sections for water vapour is evaluated and only small differences are found. Finally, a high-temperature (boundary layer ambient: 294 K) absorption cross-section of nitrogen dioxide (NO2) is introduced in the DOAS retrieval to account for potential interferences of NO2 over regions with large anthropogenic emissions, leading to improved fit quality over these areas. A comparison with vertical CHOCHO columns retrieved from GOME-2 and SCIAMACHY measurements over continental regions is performed, showing overall good consistency. However, SCIAMACHY CHOCHO columns are systematically higher than those obtained from the other instruments. Using the new OMI CHOCHO data set, the link between fires and glyoxal columns is investigated for two selected regions in Africa. In addition, mapped averages are computed for a fire event in Russia between mid-July and mid-August 2010. In both cases, enhanced CHOCHO levels are found in close spatial and temporal proximity to elevated levels of MODIS fire radiative power, demonstrating that pyrogenic emissions can be clearly identified in the new OMI CHOCHO product.

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Cornelius, Nathalie G. « Le troisième jour by Chochana Boukhobza ». French Review 85, n^o 2 (2011) : 391–92. http://dx.doi.org/10.1353/tfr.2011.0018.

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Czugler, Mátyás, Edwin Weber, László Párkányi, Petros P. Korkas et Petra Bombicz. « Supramolecular[6]Chochin and“Big Mac” Made from Chiral Piedfort Assemblies ». Chemistry - A European Journal 9, n^o 16 (18 août 2003) : 3741–47. http://dx.doi.org/10.1002/chem.200304969.

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Ortega Duarte, Alejandra, Francisco Javier Martin-Sanchez, Juan Gonzalez-Castillo et Pedro Ruiz-Artacho. « Intoxicación por «agua de chocho» ». Medicina Clínica 140, n^o 1 (janvier 2013) : 43–44. http://dx.doi.org/10.1016/j.medcli.2012.05.023.

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Campbell, R. Keith, et John R. White. « More Choces Than Ever Before ». Diabetes Educator 34, n^o 3 (mai 2008) : 518–34. http://dx.doi.org/10.1177/0145721708317870.

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Washenfelder, R. A., A. O. Langford, H. Fuchs et S. S. Brown. « Measurement of glyoxal using an incoherent broadband cavity enhanced absorption spectrometer ». Atmospheric Chemistry and Physics Discussions 8, n^o 4 (29 août 2008) : 16517–53. http://dx.doi.org/10.5194/acpd-8-16517-2008.

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Abstract. We describe an instrument for simultaneous measurements of glyoxal (CHOCHO) and nitrogen dioxide (NO2) using cavity enhanced absorption spectroscopy with a broadband light source. The output of a Xenon arc lamp is coupled into a 1 m optical cavity, and the spectrum of light exiting the cavity is recorded by a grating spectrometer with a charge-coupled device (CCD) array detector. The mirror reflectivity and effective path lengths are determined from the known Rayleigh scattering of He and dry zero air (N2+O2). Least-squares fitting, using published reference spectra, allow the simultaneous retrieval of CHOCHO, NO2, O4, and H2O in the 441 to 469 nm spectral range. For a 1-min sampling time, the minimum detectable absorption is 4×10−10 cm−1, and the precision (±1σ) on signal for measurements of CHOCHO and NO2 is 29 pptv and 20 pptv, respectively. We directly compare the incoherent broadband cavity enhanced absorption spectrometer to 404 and 532 nm cavity ringdown instruments for CHOCHO and NO2 detection, and find linear agreement over a wide range of concentrations. The instrument has been tested in the laboratory with both synthetic and real air samples, and the demonstrated sensitivity and specificity suggest a strong potential for field measurements of both CHOCHO and NO2.

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Washenfelder, R. A., A. O. Langford, H. Fuchs et S. S. Brown. « Measurement of glyoxal using an incoherent broadband cavity enhanced absorption spectrometer ». Atmospheric Chemistry and Physics 8, n^o 24 (23 décembre 2008) : 7779–93. http://dx.doi.org/10.5194/acp-8-7779-2008.

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Abstract. We describe an instrument for simultaneous measurements of glyoxal (CHOCHO) and nitrogen dioxide (NO2) using cavity enhanced absorption spectroscopy with a broadband light source. The output of a Xenon arc lamp is coupled into a 1 m optical cavity, and the spectrum of light exiting the cavity is recorded by a grating spectrometer with a charge-coupled device (CCD) array detector. The mirror reflectivity and effective path lengths are determined from the known Rayleigh scattering of He and dry zero air (N2+O2). Least-squares fitting, using published reference spectra, allow the simultaneous retrieval of CHOCHO, NO2, O4, and H2O in the 441 to 469 nm spectral range. For a 1-min sampling time, the precision (±1σ) on signal for measurements of CHOCHO and NO2 is 29 pptv and 20 pptv, respectively. We directly compare measurements made with the incoherent broadband cavity enhanced absorption spectrometer with those from cavity ringdown instruments detecting CHOCHO and NO2 at 404 and 532 nm, respectively, and find linear agreement over a wide range of concentrations. The instrument has been tested in the laboratory with both synthetic and real air samples, and the demonstrated sensitivity and specificity suggest a strong potential for field measurements of both CHOCHO and NO2.

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Šrámek, Přemysl, et Tatiana Molková. « THE DETAILED PRIORITY OF INTERNATIONAL FREIGHT EXPRESSES IN THE OVERLAPPING SECTION OF RFC 7 AND RFC 9 KOLÍN – CHOCEŇ ». Acta Polytechnica CTU Proceedings 11 (28 août 2017) : 70. http://dx.doi.org/10.14311/app.2017.11.0070.

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The main goal of this article is to research the optimal priority of international freight expresses, especially on European freight corridors. This article shows this problem in the context in the overlapping section of RFC 7 and RFC 9 Kolín – Chocen. There is solved changing priority of freight expresses in detail, whereas other train priorities are the same.

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Volkamer, R., P. J. Ziemann et M. J. Molina. « Secondary organic aerosol formation from acetylene (C2H2) : seed effect on SOA yields due to organic photochemistry in the aerosol aqueous phase ». Atmospheric Chemistry and Physics Discussions 8, n^o 4 (5 août 2008) : 14841–92. http://dx.doi.org/10.5194/acpd-8-14841-2008.

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Abstract. The lightest Non Methane HydroCarbon (NMHC), i.e. acetylene (C2H2) is found to form secondary organic aerosol (SOA). Contrary to current belief, the number of carbon atoms, n, for a NMHC to act as SOA precursor is lowered to n=2 here. The OH-radical initiated oxidation of C2H2 forms glyoxal (CHOCHO) as the highest yield product, and >99% of the SOA from C2H2 is attributed to CHOCHO. SOA formation from C2H2 and CHOCHO was studied in a photochemical and a dark simulation chamber. Further, the experimental conditions were varied with respect to the chemical composition of the seed aerosol, mild acidification with sulphuric acid (SA, 3<pH<4), and relative humidity (10<RH<90%). The rate of SOA formation is found enhanced by several orders of magnitude in the photochemical system. The SOA yields (YSOA) ranged from 1% to 20% and did not correlate with the organic mass portion of the seed, but increased linearly with liquid water content (LWC) of the seed. For fixed LWC, YSOA varied by more than a factor of five. Water soluble organic carbon (WSOC) photochemistry in the liquid water associated with internally mixed inorganic/WSOC seed aerosols is found responsible for this seed effect. WSOC photochemistry enhances the SOA source from CHOCHO, while seeds containing amino acids (AA) and/or SA showed among the lowest of all YSOA values, and largely suppress the photochemical enhancement on the rate of CHOCHO uptake. Our results give first evidence for the importance of heterogeneous photochemistry of CHOCHO in SOA formation, and identify a potential bias in the currently available YSOA data for other SOA precursor NMHCs. We demonstrate that SOA formation via the aqueous phase is not limited to cloud droplets, but proceeds also in the absence of clouds, i.e. does not stop once a cloud droplet evaporates. Atmospheric models need to be expanded to include SOA formation from WSOC photochemistry of CHOCHO, and possibly other α-dicarbonyls, in aqueous aerosols.

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Volkamer, R., P. J. Ziemann et M. J. Molina. « Secondary Organic Aerosol Formation from Acetylene (C2H2) : seed effect on SOA yields due to organic photochemistry in the aerosol aqueous phase ». Atmospheric Chemistry and Physics 9, n^o 6 (19 mars 2009) : 1907–28. http://dx.doi.org/10.5194/acp-9-1907-2009.

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Abstract. The lightest Non Methane HydroCarbon (NMHC), i.e., acetylene (C2H2) is found to form secondary organic aerosol (SOA). Contrary to current belief, the number of carbon atoms, n, for a NMHC to act as SOA precursor is lowered to n=2 here. The OH-radical initiated oxidation of C2H2 forms glyoxal (CHOCHO) as the highest yield product, and >99% of the SOA from C2H2 is attributed to CHOCHO. SOA formation from C2H2 and CHOCHO was studied in a photochemical and a dark simulation chamber. Further, the experimental conditions were varied with respect to the chemical composition of the seed aerosols, mild acidification with sulphuric acid (SA, 3<pH<4), and relative humidity (10<RH<90%). The rate of SOA formation is found enhanced by several orders of magnitude in the photochemical system. The SOA yields (YSOA) ranged from 1% to 24% and did not correlate with the organic mass portion of the seed, but increased linearly with liquid water content (LWC) of the seed. For fixed LWC, YSOA varied by more than a factor of five. Water soluble organic carbon (WSOC) photochemistry in the liquid water associated with internally mixed inorganic/WSOC seed aerosols is found responsible for this seed effect. WSOC photochemistry enhances the SOA source from CHOCHO, while seeds containing amino acids (AA) and/or SA showed among the lowest of all YSOA values, and largely suppress the photochemical enhancement on the rate of CHOCHO uptake. Our results give first evidence for the importance of heterogeneous photochemistry of CHOCHO in SOA formation, and identify a potential bias in the currently available YSOA data for other SOA precursor NMHCs. We demonstrate that SOA formation via the aqueous phase is not limited to cloud droplets, but proceeds also in the absence of clouds, i.e., does not stop once a cloud droplet evaporates. Atmospheric models need to be expanded to include SOA formation from WSOC photochemistry of CHOCHO, and possibly other α-dicarbonyls, in aqueous aerosols.

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Kaiser, J., G. M. Wolfe, K. E. Min, S. S. Brown, C. C. Miller, D. J. Jacob, J. A. deGouw et al. « Reassessing the ratio of glyoxal to formaldehyde as an indicator of hydrocarbon precursor speciation ». Atmospheric Chemistry and Physics 15, n^o 13 (13 juillet 2015) : 7571–83. http://dx.doi.org/10.5194/acp-15-7571-2015.

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Abstract. The yield of formaldehyde (HCHO) and glyoxal (CHOCHO) from oxidation of volatile organic compounds (VOCs) depends on precursor VOC structure and the concentration of NOx (NOx = NO + NO2). Previous work has proposed that the ratio of CHOCHO to HCHO (RGF) can be used as an indicator of precursor VOC speciation, and absolute concentrations of the CHOCHO and HCHO as indicators of NOx. Because this metric is measurable by satellite, it is potentially useful on a global scale; however, absolute values and trends in RGF have differed between satellite and ground-based observations. To investigate potential causes of previous discrepancies and the usefulness of this ratio, we present measurements of CHOCHO and HCHO over the southeastern United States (SE US) from the 2013 SENEX (Southeast Nexus) flight campaign, and compare these measurements with OMI (Ozone Monitoring Instrument) satellite retrievals. High time-resolution flight measurements show that high RGF is associated with monoterpene emissions, low RGF is associated with isoprene oxidation, and emissions associated with oil and gas production can lead to small-scale variation in regional RGF. During the summertime in the SE US, RGF is not a reliable diagnostic of anthropogenic VOC emissions, as HCHO and CHOCHO production are dominated by isoprene oxidation. Our results show that the new CHOCHO retrieval algorithm reduces the previous disagreement between satellite and in situ RGF observations. As the absolute values and trends in RGF observed during SENEX are largely reproduced by OMI observations, we conclude that satellite-based observations of RGF can be used alongside knowledge of land use as a global diagnostic of dominant hydrocarbon speciation.

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Albuja Landi, Ana Karina, Paola Fernanda Arguello Hernández, Sandra Noemí Escobar Arrieta et Verónica Yolanda Buenaño Suárez. « Calidad microbiológica del ceviche de chochos (Lupinus mutabilis) expendido en la vía pública de la ciudad de Riobamba – Ecuador ». LA CIENCIA AL SERVICIO DE LA SALUD Y NUTRICIÓN 12, n^o 1 (22 juin 2021) : 86–93. http://dx.doi.org/10.47187/cssn.vol12.iss1.142.

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Introducción: El ceviche de chochos, patrimonio alimentario de la ciudad de Riobamba-Ecuador, se expende en puestos de venta fijos y ambulantes. Este producto de consumo masivo es preparado a base de jugo de tomate, cuero de chancho, especias y chochos desamargados. Objetivo: Evaluar la calidad microbiológica de los ceviches de chochos, comercializados en la vía pública en sitios de mayor concurrencia de la ciudad de Riobamba. Métodos: Estudio observacional, descriptivo de corte transversal. Para esto se realizó el recuento de bacterias indicadoras de calidad microbiológica (Aerobios mesófilos, Staphylococcus aureus, Salmonella spp. y Coliformes totales) y el análisis parasitológico de muestras obtenidas por duplicado de 14 puestos de venta, utilizando las normas técnicas ecuatorianas pertinentes. Resultados: Los resultados muestran deficiente calidad sanitaria del producto, los recuentos sobrepasan los límites establecidos en el Reglamento Sanitario de los Alimentos-Chile Dto. N° 977/96 y Norma sanitaria NTS N° 071- MINSA/DIGESA-V.01.2008 del Perú. El 100% de las muestras presentó recuentos altos de aerobios mesófilos, el 85.7 % para S. aureus, 42.8% para coliformes totales, en cuanto a Samonella spp. en el 35.7% de las muestras se confirmó su presencia hasta pruebas bioquímicas. Finalmente, en el 71.42% se observaron parásitos. Conclusiones: Los ceviches de chochos pueden convertirse en un potencial transmisor de enfermedades. Sugiriendo a las autoridades de control sanitario, la vigilancia sanitaria, en la elaboración de estos productos, así como la capacitación y concienciación a los manipuladores de la aplicación de las prácticas correctas de higiene.

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Fernández Jeri, Armstrong Barnard, et Marilú Mestanza Mendoza. « Influencia de la fortificación con pasta de Oncorhynchus mykiss "trucha" y harina de Lupinus mutabilis "chocho" en el sabor y dureza de galletas ». Revista Científica UNTRM : Ciencias Naturales e Ingeniería 2, n^o 1 (21 novembre 2017) : 40. http://dx.doi.org/10.25127/ucni.v2i1.224.

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El objetivo de la presente investigación fue determinar la influencia de la fortificación con pasta de Oncorhynchus mykiss "trucha" y harina de Lupinus mutabilis "chocho" sobre el sabor y dureza de galletas. La trucha fresca tuvo un peso promedio de 250 gy se evaluó cuatro formulaciones, TI (5% pescado y 0% chocho), T2 (5% de chocho y 10% pescado), T3 (10% de chocho y 15% pescado) y T4 (10% de chocho y 10% pescado) y un control C (0% pescado y 0% chocho), todos con tres repeticiones. Para la preparación de galletas se preparó la pasta de pescado que se mezcló con los demás ingredientes; luego se amasó y moldeó en forma laminar. Se puso enun horno de 140 - 170ºC. En las galletas obtenidas se evaluó la humedad, la acidez total y el pH; así como el sabor y dureza. Se obtuvo una galleta con un pH ligeramente ácido y los mejores valores sensoriales fueron para los tratamientos T2 y T4; siendo T2 la formulación de mayor aceptación.

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Kang, Kyoung Min. « Reflections on the characteristics and community of Wasanbuldotdang in Chocheon, Jeju City ». Korean Shanmanism 45 (31 août 2022) : 7–31. http://dx.doi.org/10.54269/akss.2022.08.45.7.

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Liang, Shuaixi, Min Qin, Pinhua Xie, Jun Duan, Wu Fang, Yabai He, Jin Xu et al. « Development of an incoherent broadband cavity-enhanced absorption spectrometer for measurements of ambient glyoxal and NO2 ; in a polluted urban environment ». Atmospheric Measurement Techniques 12, n^o 4 (24 avril 2019) : 2499–512. http://dx.doi.org/10.5194/amt-12-2499-2019.

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Abstract. We report the development of an instrument for simultaneous fast measurements of glyoxal (CHOCHO) and NO2 based on incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) in the 438–465 nm wavelength region. The highly reflective cavity mirrors were protected from contamination by N2 purge gas. The reduction of the effective cavity length was calibrated by measuring collision-induced oxygen absorption at ∼477 nm of pure oxygen gas input with and without the N2 mirror purge gas. The detection limits of the developed system were evaluated to be 23 parts per trillion by volume (pptv, 2σ) for CHOCHO and 29 pptv (2σ) for NO2 with a 30 s acquisition time. A potential cross-interference of NO2 absorption on accurate CHOCHO measurements has been investigated in this study, as the absorption of NO2 in the atmosphere could often be several hundred-fold higher than that of glyoxal, especially in contaminated areas. Due to non-linear spectrometer dispersion, simulation spectra of NO2 based on traditional convolution simulation did not match the measurement spectra well enough. In this work, we applied actual NO2 spectral profile measured by the same spectrometer as a reference spectral profile in subsequent atmospheric spectral analysis and retrieval of NO2 and CHOCHO concentrations. This effectively reduced the spectral fitting residuals. The instrument was successfully deployed for 24 d of continuous measurements of CHOCHO and NO2 in the atmosphere in a comprehensive field campaign in Beijing in June 2017.

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Leroux, Killian, Jean-Claude Guillemin et Lahouari Krim. « Solid-state formation of CO and H2CO via the CHOCHO + H reaction ». Monthly Notices of the Royal Astronomical Society 491, n^o 1 (13 novembre 2019) : 289–301. http://dx.doi.org/10.1093/mnras/stz3051.

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ABSTRACT Glycolaldehyde (CHOCH2OH) and ethylene glycol (HOCH2CH2OH) are among many complex organic molecules detected in the interstellar medium (ISM). Astrophysical models proposed very often that the formation of these compounds would be directly linked to the hydrogenation of glyoxal (CHOCHO), a potential precursor which is not yet detected in the ISM. We have performed, in this work, surface and bulk hydrogenations of solid CHOCHO under ISM conditions in order to confirm or invalidate the astrophysical modelling of glyoxal transformation. Our results show that the hydrogenation of glyoxal does not lead to the formation of detectable amounts of heavier organic molecules such as glycolaldehyde and ethylene glycol but rather to lighter CO-bearing species such as CO, H2CO, and CO–H2CO, a reaction intermediate resulting from an H-addition–elimination process on CHOCHO and where CO is linked to H2CO. The solid phase formation of such a reaction intermediate has been confirmed through the neon matrix isolation of CO–H2CO species. Additionally, the CHOCHO + H solid-state reaction might also lead to the production of CH3OH formed under our experimental conditions as a secondary product resulting from the hydrogenation of formaldehyde.

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Sánchez Aguilera, Damaris Dalia, Stalin Gustavo Santacruz Terán, Daniel Ricardo Aguayo Pino, Karol Yannela Revilla Escobar, María Laura Carrillo Pisco et Jhonnatan Placido Aldas Morejon. « CARACTERIZACIÓN FISICOQUÍMICA DE FRÉJOL CANARIO (Vigna unguiculata) Y CHOCHO GUARANGUITO (Lupinus mutabilis) Y SU INCIDENCIA EN LA FUNCIONALIDAD DE HARINAS ». Revista Bases de la Ciencia 8, n^o 1 (19 avril 2023) : 38–50. http://dx.doi.org/10.33936/revbasdelaciencia.v8i1.5452.

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Las leguminosas tienen un gran aporte nutricional y sus propiedades funcionales, entre las más importante para la alimentación destacan el fréjol canario (V. unguiculata) y el chocho guaranguito (L. mutabilis). Debido a su bajo costo, es accesible para las personas, sin embargo, los consumidores desconocen de su valor nutricional, exceptuando la importancia de estas leguminosas que, gracias a su gran contenido de proteína, vitaminas y minerales, se podrían considerar como una excelente alternativa de alimentación saludable. Por esta razón, la presente investigación tuvo como objetivo evaluar las características fisicoquímica de las leguminosas fréjol y chocho y su incidencia en la funcionalidad de harinas. Lo cual permitió determinar que el chocho mostró mayor contenido proteico 40,69 % y de lípidos 11,04 %, mientras que el fréjol canario tuvo mayor contenido de carbohidratos totales 75,12 %. Por otro lado, en relación a la funcionalidad de las harinas, la obtenida del fréjol se situó un mayor contenido en WHC (142,62 ml/100 g) y OAC (148, 03 ml/100 g), FS (96,71 %), EA (29,48 %), ES (42,30 %), FC (16,00 %), en comparación a la harina del chocho que presentó mejores capacidades en WAC (157,82 ml/100 g) y OHC (151,05 ml/100 g).

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Seraquive Minga, Ángel Hilario, et Franklin Alfredo Iñiguez Heredia. « Niveles de Adición de Harina de Chocho, Lupinus Mutabilis, en la Elaboración de Quesos Frescos Artesanales ». Ciencia Latina Revista Científica Multidisciplinar 8, n^o 1 (9 avril 2024) : 10472–80. http://dx.doi.org/10.37811/cl_rcm.v8i1.10353.

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Esta investigación se centra en los efectos de la incorporación de harina de chocho en la elaboración de quesos frescos artesanales, explorando su impacto en el contenido proteico, de fibra y las características organolépticas de los productos lácteos. Los objetivos incluyen la determinación de niveles óptimos de adición de harina de chocho para lograr quesos frescos altamente proteicos, evaluando rigurosamente la calidad microbiológica y estableciendo un protocolo de elaboración que garantice tanto la seguridad como la excelencia sensorial de los productos finales. La hipótesis planteada sugiere que la adición de harina de chocho puede aumentar significativamente el contenido de proteínas y fibra en los quesos, sin comprometer sus cualidades organolépticas y funcionales. Los resultados obtenidos indican que la adición de harina de chocho, especialmente al 10%, mejora el perfil sensorial y nutricional de los quesos, ofreciendo beneficios en términos de sabor y digestibilidad. Aunque se observa una posible afectación en la apariencia, se identifica el 10% como el nivel óptimo para mantener la calidad global del producto. Este hallazgo posee implicaciones significativas para la industria alimentaria ecuatoriana al mejorar sustancialmente el valor nutricional de los quesos frescos artesanales, potencialmente atrayendo a consumidores interesados en opciones más saludables.

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ACUÑA-TARAZONA, MARGOTH, ERIC HAGSATER et ELIZABETH SANTIAGO AYALA. « Epidendrum choccei (Orchidaceae), a new species from Northern Peru ». Phytotaxa 394, n^o 1 (25 février 2019) : 98. http://dx.doi.org/10.11646/phytotaxa.394.1.7.

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Nogué, Santiago, Jorge Arbulú et Cèsar Blanché. « Toxicidad por el «agua de chocho» ». Medicina Clínica 141, n^o 6 (septembre 2013) : 274–75. http://dx.doi.org/10.1016/j.medcli.2013.01.046.

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Yuwita, Aulia Mawar, et Nyayu Masyita Ariani. « Lembar Kerja Siswa untuk Kemampuan Penalaran Matematis Siswa SMP Kelas VIII ». VYGOTSKY 2, n^o 2 (31 août 2020) : 126. http://dx.doi.org/10.30736/vj.v2i2.275.

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Penelitian ini bertujuan menghasilkan Lembar Kerja Siswa untuk kemampuan penalaran matematis siswa SMP dengan model pembelajaran Auditory Intellectually and Repetition. Subjek yang menjadi fokus penelitian adalah siswa SMPN 20 Kota Bengkulu kelas VIII. Digunakan model 4-D dalam pengembangan LKS ini. Penelitian ini dilakukan pada tanggal 27 Januari-27 Februari 2020. LKS yang dihasilkan telah valid berdasarkan pertimbangan 3 validator dan uji Q Chochran. Uji Q Chochran menunjukkan hasil Q hitung lebih kecil dari tabel taraf signifikasi , yang artinya ketiga validator sepakat bahwa LKS valid. Hasil yang didapatkan pada uji kepraktisan memenuhi kriteria kepraktisan tinggi dengan skor keprakatisan rata-rata secara keseluruhan adalah sebesar 3,53.

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KUME, Masashi, Mamoru KOJIMA, Syun KOJIMA, Mio ARAI, Masaki SAKATA, Natumi SASAOKA, Akihiko GOTO, Tetuya YOSHIDA et Hiroyuki HAMADA. « 405 Comparison of motion concerning making "Kyo-Chochin" in expert and non-expert ». Proceedings of the Materials and processing conference 2010.18 (2010) : _405–1_—_405–2_. http://dx.doi.org/10.1299/jsmemp.2010.18._405-1_.

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DÁVALOS, LILIANA M. « A New Chocoan Species of Lonchophylla (Chiroptera : Phyllostomidae) ». American Museum Novitates 3426 (février 2004) : 1–14. http://dx.doi.org/10.1206/0003-0082(2004)426<0001:ancsol>2.0.co;2.

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Kang, Yanyu, Guiqian Tang, Qihua Li, Baoxian Liu, Dan Yao, Yiming Wang, Yinghong Wang, Yuesi Wang et Wenqing Liu. « Problems with and Improvement of HCHO/NO2 for Diagnosing Ozone Sensitivity—A Case in Beijing ». Remote Sensing 15, n^o 8 (9 avril 2023) : 1982. http://dx.doi.org/10.3390/rs15081982.

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Rfn (formaldehyde/nitrogen dioxide) is a common indicator based on satellite observations used to classify ozone formation sensitivity. However, it may underestimate anthropogenic volatile organic compounds (VOCs) in heavily polluted cities when only formaldehyde (HCHO) is used in Rfn to measure VOCs, since it is mainly derived from natural sources worldwide. In this study, we used multiaxis differential optical absorption spectroscopy to acquire tropospheric observations of nitrogen dioxide (NO2), HCHO and glyoxal (CHOCHO) in Beijing from 1 April 2019 to 31 March 2020. Combined with VOCs detected simultaneously by gas chromatography—mass spectrometry and proton transfer reaction–time-of-flight/mass spectrometry near the ground, we evaluated the representativeness of HCHO column densities on total VOCs (TVOC) in equivalent propylene concentrations, which is called reactivity. The results showed that there were significant seasonal differences in the response of HCHO to TVOC reactivity, with fitting slopes of 2.3 (spring), 2.6 (summer), 2.9 (autumn) and 1.0 (winter) in the four seasons, respectively. Since CHOCHO can be used to partly characterize the contribution of anthropogenic VOC emissions and demonstrated a better response to TVOC reactivity in winter, with fitting slopes of 0.2 (spring), 0.2 (summer), 0.2 (autumn) and 0.5 (winter) in the four seasons, respectively, we introduced CHOCHO to construct a new indicator (HCHO + 6 × CHOCHO). The fitting slopes of the four seasons were more similar, being 3.2 (spring), 3.6 (summer), 4.0 (autumn) and 4.0 (winter). The ratio of the new indicator to NO2, Rmn ((HCHO + 6 × CHOCHO)/NO2), was used to reclassify the ozone formation sensitivity of urban areas in North China, revealing that it is a transition regime before 1300 LST (LST = UST + 8) and an NOx-limited regime afterwards. Rmn improved the sensitivity from the VOC-limited regime to the NOx-limited regime, enhancing the sensitivity of NOx and providing new robust support for ozone pollution prevention and control.

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Zurita Gallegos, Ronald Mauricio, Byron Adrián Herrera Chávez et Jessica Alexandra Robalino Vallejo. « Análisis químico, microbiológico y sensorial de helados de mora (Rubus glaucus Benth) a base de leche de chocho (Lupinus mutabilis Sweet). » Ciencia Digital 4, n^o 3 (25 août 2020) : 391–403. http://dx.doi.org/10.33262/cienciadigital.v4i3.1443.

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Se realizó un análisis químico, microbiológico y sensorial de los helados de mora (Rubus glaucus Benth) a base de leche de chocho (Lupinus mutabilis Sweet). Se aplicó un diseño experimental DBCA con tres tratamientos y tres repeticiones para la leche de chocho y los helados de mora. La información fue analizada en el programa SPSS, mediante ANOVA y la prueba de Duncan para los contenidos de proteína, grasa, sólidos totales y cenizas. Se realizó un test con un grupo de estudio de 36 degustadores, donde se utilizó una escala hedónica verbal. La leche de chocho del tratamiento T 3 (LHC3) fue considerado como el mejor tratamiento para la elaboración del helado con proteína 4.17%, grasa 2.18%, sólidos totales 6.77%, cenizas 0.20%. Para el helado de mora, el tratamiento más aceptado fue T 1 (HLM1) con proteína 6.21 %, grasa 2.20 %, sólidos totales17.84 %, cenizas 0.58 % siendo aptos para el consumo.

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Mishra, Bhupesh Kumar, Makroni Lily, Arup Kumar Chakrabartty, Debajyoti Bhattacharjee, Ramesh Chandra Deka et Asit K. Chandra. « Theoretical investigation of atmospheric chemistry of volatile anaesthetic sevoflurane : reactions with the OH radicals and atmospheric fate of the alkoxy radical (CF3)2CHOCHFO : thermal decomposition vs. oxidation ». New J. Chem. 38, n^o 7 (2014) : 2813–22. http://dx.doi.org/10.1039/c3nj01408h.

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Del Val de Gortari, Ek, et Ana Isabel Moreno-Calles. « La paradoja de los chapulines ». Herreriana 4, n^o 1 (5 juillet 2022) : 6–10. http://dx.doi.org/10.29057/h.v4i1.8741.

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Los chapulines o chochos son insectos comunes en México pertenecientes al orden Orthoptera, considerados como plagas agrícolas en algunas regiones y consumidos en otras. El consumo de chapulines en el sur del país es una tradición que se ha mantenido desde la época prehispánica. En la actualidad se ha acentuado esta percepción regional debido al aumento poblacional de los chapulines en aquellas zonas que son consideradas como una plaga. Este artículo plantea que es posible cosechar a los abundantes chapulines para ser consumidos en regiones que no son tradicionalmente entomófagas. Asimismo, se incluye información sobre su manejo y recolección, una receta de cómo cocinarlos, y se describen algunos retos y perspectivas sobre el consumo de chapulines o chochos en la actualidad.

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Kaiser, J., G. M. Wolfe, K. E. Min, S. S. Brown, C. C. Miller, D. J. Jacob, J. A. deGouw et al. « Reassessing the ratio of glyoxal to formaldehyde as an indicator of hydrocarbon precursor speciation ». Atmospheric Chemistry and Physics Discussions 15, n^o 5 (4 mars 2015) : 6237–75. http://dx.doi.org/10.5194/acpd-15-6237-2015.

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Abstract. The yield of formaldehyde (HCHO) and glyoxal (CHOCHO) from oxidation of volatile organic compounds (VOCs) depends on precursor VOC structure and the concentration of NOx (NOx = NO +NO2). Previous work has proposed that the ratio of CHOCHO to HCHO (RGF) can be used as an indicator of precursor VOC speciation, and absolute concentrations of the oxidation products as indicators of NOx. Because this metric is measurable by satellite, it is potentially useful on a global scale; however, absolute values and trends in RGF have differed between satellite and ground-based observations. To investigate potential causes of previous discrepancies and the usefulness of this ratio, we present measurements of CHOCHO and HCHO over the Southeast United States (SE US) from the 2013 SENEX flight campaign and compare these measurements with OMI satellite retrievals. High time-resolution flight measurements show that high RGF is associated with monoterpene emissions, low RGF is associated with isoprene oxidation, and emissions associated with oil and gas production can lead to small-scale variation in regional RGF. During the summertime in the SE US, RGF is not a reliable diagnostic of anthropogenic VOC emissions, as HCHO and CHOCHO production are dominated by isoprene oxidation. Our results show that the new glyoxal retrieval algorithm reduces the previous disagreement between satellite and in situ RGF observations. We conclude that satellite-based observations of RGF can be used alongside other measurements as a global diagnostic of the chemical conditions leading to secondary pollutant formation.

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