Atmospheric Research Articles

‘Sungold’ Kivi Çeşidinin Kalite Özellikleri Üzerine Modifiye Atmosfer Paketlemenin Etkisi

Bu çalışma; soğukta muhafaza süresince ‘Sungold’ (Actinidia chinensis) kivi çeşidinin ağırlık kaybı, meyve eti sertliği, suda çözünür kuru madde miktarı (SÇKM), titre edilebilir asitlik içeriği, meyve et rengi değişimi, toplam fenolik maddeler, etilen üretim miktarı ile fizyolojik ve patolojik bozukluklar gibi kalite özellikleri üzerine modifiye atmosfer paketleme (MAP) uygulamasının etkisini belirlemek için yürütülmüştür. Bu amaçla meyveler; 1.0 °C ± 0.5 °C sıcaklık ve %90-95 oransal nem koşullarında 150 gün süreyle muhafaza edilmişlerdir. Soğukta muhafazanın tüm ölçüm dönemlerinde MAP içerisinde muhafaza edilen meyvelerin ağırlık kaybının, kontrol meyvelerine kıyasla önemli derecede daha düşük olduğu belirlenmiştir. Aynı zamanda meyve eti sertliğinin korunması, suda çözünür kuru madde miktarındaki artışın yavaşlaması, titre edilebilir asitlik miktarındaki düşüşün sınırlanması, etilen üretiminin baskılanması ve iç çökmesi oranının düşüklüğü kapsamında MAP uygulaması özellikle 60 gün depolamadan itibaren, kontrol meyvelerine kıyasla daha olumlu sonuçlar vermiştir. Sonuç olarak ‘Sungold’ kivi çeşidinde herhangi bir uygulama yapılmadan 60 gün süreyle muhafaza edilebilmenin mümkün olduğu, bununla birlikte MAP uygulamasıyla bu çeşidin, 150 gün süreyle kalitenin korunarak muhafaza edilebildiği saptanmıştır.

Musa Acuminata Banana Bunch-Based Activated Carbon for Adsorption of Cu(II) Ions in Aqueous Solution: Kinetic and Isotherm Studies

Activated carbon prepared from Musa Acuminata banana bunch (AC-MABB) was proposed in this study. The active sites and morphology structure of three types of the AC-MABB were analysed using FTIR and SEM, respectively. The effect of independent variables namely contact time, Cu(II) ions concentration in solution, NaOH activator concentration, initial pH and temperature on adsorption capacity of the AC-MABB were investigated through batch mode experiments. The Cu(II) ions adsorbed onto the AC-MABB showed excellent fitting to the pseudo second-order adsorption kinetic with a correlation coefficient value of 0.999. Meanwhile it followed Langmuir isotherm with coefficient value of 0.981 and 0.991 at 27 and 57 oC, respectively. The optimum adsorption condition for 1 g of the AC-MABB was observed to be under 0.4 M NaOH activation atmosphere and, stirred at initial pH of 5 with a speed of 100-rpm and a pressure of 1 atm. The maximum Cu(II) ions adsorption capacity based on Langmuir was identified approximately equal to 40.322 and 46.082 mg/g at 27 and 57 oC, respectively.

Direct Radiative Forcing Induced by Light‐Absorbing Aerosols in Different Climate Regions Over East Asia

AbstractLight‐absorbing aerosols (LAAs), mainly composed of black carbon (BC) and dust aerosols, are responsible for significant climate forcing through their strong absorption of solar radiation. A fully coupled meteorology‐chemistry model (WRF‐Chem) associated with satellite retrievals and in situ measurements is used to investigate the direct radiative forcing (DRF) induced by LAAs in different climate regions over East Asia. Results show that the annual all‐sky dust and BC DRF are −0.84 and 1.06 W m−2 at the top of atmosphere (TOA), −1.23 and −1.55 W m−2 at the surface (SUR), and 0.39 and 2.61 W m−2 within the atmosphere (ATM) over East Asia. Large LAAs DRF can be found in hyper‐arid, subhumid, and humid regions at the SUR and ATM where dust DRF dominates the surface cooling effect, while BC DRF is predominant in the eminent warming effect on ATM in most climate regions. The meteorological conditions in hyper‐arid region are associated with enhanced surface wind and weakened atmospheric wind, which is in favor of the emission and accumulation of dust supporting the positive LAAs DRF anomalies higher than 10 W m−2 in hyper‐arid region. The positive geopotential height anomalies over Northeast China weaken the westerly winds, which is beneficial to the accumulation of LAAs, and results in the positive LAAs DRF anomalies of 3 W m−2 in semiarid regions. The large LAAs mass loading, strong aerosol absorptive ability, and decreased cloudiness caused by northerly anomalies are responsible for the high LAAs DRF in humid region.

Black Carbon aerosol characteristics and radiative forcing over the high altitude glacier region of Himalaya-Karakorum-Hindukush

Abstract Absorbing aerosols mainly Black Carbon (BC) have potential effects on the hydrological cycle and climate change over the high-altitude regions particularly in South Asia. The BC measurements are sparse in high altitude locations of the world particularly over the Northern regions of Pakistan. This study investigated the diurnal/monthly variations of BC and its climatic impacts during the period of 2016–2017 over four high altitude locations, i.e., Astore, Gilgit, Sost and Skardu located in the Himalaya-Karakorum-Hindukush (HKH) mountain ranges in Northern Pakistan. The Optical Properties of Aerosols and Clouds (OPAC) model was used for the estimation of aerosol optical properties, e.g., Aerosol Optical Depth (AOD), Asymmetry Parameter (AP) and Single Scattering Albedo (SSA) using the BC number density corresponding to the BC mass concentration. Then the model derived optical properties (AOD, AP and SSA), surface reflectance, ozone and water vapor were used in Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model for the calculation of BC aerosol radiative forcing (ARF) at the Top Of Atmosphere (TOA), Surface (SUR) and within the ATMosphere (ATM). The results revealed that the mean monthly BC concentrations were maximum during November (3.05 ± 0.7 μg/m3) as well as in December (3.05 ± 0.5 μg/m3) at Gilgit and minimum during August (1.1 ± 0.3 μg/m3) at Sost. Correspondingly, the diurnal variation of BC concentrations displayed strong fluctuations, with high concentrations in the late night and early morning during November and December for Astore and Gilgit, respectively. Generally, the BC concentrations were maximum/minimum in the morning/evening during May, June, August and September at all locations. The correlation of BC with different meteorological parameters showed that the BC has positive correlation with temperature and wind speed, while negative with relative humidity and rainfall. The HYSPLIT back trajectory analysis revealed that air masses arrived the study locations from both long distance (Turkmenistan, Tajikistan, Uzbekistan, Iran, Afghanistan, India, and China) and local sources. The monthly mean maximum and minimum BC ARF values at SUR (TOA) were found to be −43.7 ± 3.0 W/m2 (−8.2 ± 0.2 W/m2) and −16.4 ± 1.0 W/m2 (−1.2 ± 0.1 W/m2), respectively, giving an averaged atmospheric forcing of 35.7 ± 2.3 W/m2 and 15.2 ± 1.9 W/m2.

In the Atmosphere: The politics of Mati Diop's Atlantics

The Yale ReviewVolume 108, Issue 2 p. 186-191 REVIEW In the Atmosphere: The politics of Mati Diop's Atlantics Lindsay Turner, Author of Songs & Ballads and the translator of several books of contemporary Francophone poetry and philosophy.Search for more papers by this author Lindsay Turner, Author of Songs & Ballads and the translator of several books of contemporary Francophone poetry and philosophy.Search for more papers by this author First published: 07 July 2020 https://doi.org/10.1111/yrev.13647AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Volume108, Issue2Summer 2020Pages 186-191 RelatedInformation

Gender Differences in Senior High School Science Students’ Perceptions of Their Teachers’ Classroom Management Strategies in New-Juaben Municipality of Ghana

This study explored gender differences associated with science students’ perception of their educators’ classroom management strategies used in the learning and teaching of science. A cross-sectional survey design was used for the investigation, which took place in three senior high schools offering the General Science programme in the New-Juaben Municipal (Koforidua), in the Eastern Region of Ghana. A sample of 300 third year (SHS 3) senior high school students in the 2018/2019 academic year were selected using a random sampling procedure to respond to a Self-Report Survey Questionnaire with closed-ended and open-ended questions. The questionnaire was adapted from the Technology-Rich outcomes-focused Learning Environment Inventory -TROFLEI) to suit the study design and was pre-tested to ensure that the statements were reliable and valid. The results from the study revealed that there are clear differences between genders regarding educators’ classroom management strategies. One other key finding from the study was students’ indecision as to the extent to which their teachers use the 10 classroom management strategies prescribed to be used by teachers. It was therefore recommended among others for educators to create an empowering technology-rich classroom atmosphere for learners to actively partake in classroom activities.

Aproximaciones a la experiencia estética de a cueca chilena: la fiesta como perspectiva estética y filosófica

En este artículo se aborda el fenómeno de la cueca chilena, específicamente su vertiente urbana, como experiencia estética, desde los elementos que residen en ella: la lírica popular, el baile y el canto englobados en la expresión de la farra o fiesta. Para ello, se revisará la pertinencia de este estudio dentro de la filosofía, con sus roces con otras disciplinas y los propios límites del lenguaje filosófico para abordarla. Desde el trabajo del filósofo chileno Fidel Sepúlveda y de Hans-Georg Gadamer, estudiaremos sus componentes formales para observar el fenómeno en su dimensión estética. El artículo culmina proponiendo una mirada distinta para abordar esta experiencia estética a partir del ambiente, como una nueva perspectiva para emprender un estudio estético y filosófico.

Evaluation of future climate change scenarios in urban heat island and its neighborhood using dynamical downscaling

According to IPCC reports, global climate change is likely to be accompanied by a greater frequency, intensity, and duration of heat waves in urban areas. This is related to predicted and ongoing variation of atmospheric temperature and its association with the dynamical evolution of cities. Changes in the roughness pattern of the surface, wind intensity, soil available humidity and radiative properties compared to the natural surfaces characterize the formation of the Urban Heat Island (UHI). A dynamical downscaling of A2 and B1 SRES’s future scenarios from Intergovernmental Panel on Climate Change were performed for Londrina, a medium-size city of Southern Brazil, using the Weather Research and Forecasting model. The main objective of this study is to investigate the impact of these scenarios on the UHI formation and intensity based on different input data, and its role and influence in the rural area. For this, an evaluation of the model and a comparison with the scenarios were done to mitigate the current trends. The results show a tendency in the current situation in following the pessimistic A2 scenario. Also, a drier rural area for the sustainable projection (B1) is found which implicates in a higher temperature and wind patterns modification for both sites, urban and rural region. Both future projections have a direct influence on the UHI intensity and formation, yielding effects in the agriculture and affecting conditions on human comfort over the region. (Less)

Black carbon aerosols over a high altitude station, Mahabaleshwar: Radiative forcing and source apportionment

Observations of Black Carbon (BC) aerosol concentrations were carried at Mahabaleshwar, a high altitude station in southwest India during March 2017–February 2019 using an Aethalometer (AE42) from Magee Scientific. BC concentration at Mahabaleshwar, varied from 0.016 μg/m3 to 16.03 μg/m3, with an average of 1.56 ± 0.88 μg/m3, indicating significant burden of these absorbing aerosols even at the free tropospheric altitudes (1348 m AMSL) as the station height remains above the Mixing Layer Height (MLH) throughout the year (MLH varies from 60 to 1293.6 m). BC is found to exhibit strong seasonal variation with the maximum concentration during winter and minimum during monsoon. The concentrations of BC, BC from fossil fuel (BCff), and BC from biomass burning (BCbb) exhibit diurnal variation with maximum values in the morning and evening hours and lower values around the afternoon due to the changes in the mixing layer height. The BCff and BCbb show the maximum value in winter (BCff: 1.47 μg/m3, BCbb: 0.69 μg/m3) which may be due to more biomass burning activity in the surrounding area along with the lower atmospheric temperatures and wind speeds which trap the pollution near the surface. However, in summer and post-monsoon the BCff remains around 1.0 μg/m3 and BCbb remains around 0.4 μg/m3. The lowest values of BCff (0.47 μg/m3) and BCbb (0.15 μg/m3) are exhibited in monsoon. Large negative radiative forcing was observed at the surface (SUF) and at top of atmosphere (TOA) whereas that at the atmosphere (ATM) was positive during all the seasons for both composite aerosol and without BC scenarios thus inferring to the significant cooling at SUF and warming at ATM leading to high atmospheric heating rates. Overall, the contribution of BC to the total atmospheric aerosol radiative forcing (ARF) was found to be 43% for the whole observational period. Temporal variations of MLH, BCff, and BCbb along with meteorological parameters and bivariate analysis of winds with respect to BC have been also discussed.

‘The surface becomes a part of the atmosphere’: light as medium in László Moholy-Nagy’s aesthetics of dematerialization

‘The surface becomes a part of the atmosphere’: light as medium in László Moholy-Nagy’s aesthetics of dematerialization

Large eddy simulation of blockage effects in the assessment of wind effects on tall buildings

The blockage effect on the aerodynamic characteristics of tall buildings is a fundamental issue in wind tunnel test but has rarely been addressed. To evaluate the blockage effects on the aerodynamic forces on a square tall building and flow field peripherally, large eddy simulations (LES) were performed on a 3D square cylinder with an aspect ratio of 6:1 under the uniform smooth inflow and turbulent atmospheric boundary layer (ABL) inflow generated by the narrowband synthesis random flow generator (NSRFG). First, a basic case at a blockage ratio (BR) of 0.8% was conducted to validate the adopted numerical methodology. Subsequently, simulations were systematically performed at 6 different BRs. The simulation results were compared in detail to illustrate the differences induced by the blockage, and the mechanism of the blockage effects under turbulent inflow was emphatically analysed. The results reveal that the pressure coefficients, the aerodynamic forces, and the Strouhal number increase monotonically with BRs. Additionally, the increase of BR leads to more coherence of the turbulent structures and the higher intensity of the vortices in the vicinity of the building. Moreover, the blockage effects on the aerodynamic forces and flow field are more significant under smooth inflow than those under turbulent inflow.

Changes in the Rotation Axis of Earth After Asteroid/Cometary Impacts and their Geological Effects

In this paper sudden shifts of the poles are proposed as an explanation for the recurrent geological crisis during which volcanic eruptions, orogenesis, climatic changes, sea levels variations, together with mass extinctions occur. Such shifts are usually considered impossible on the assumption that only a planetary impact could change in a significant way the Earth’s momentum. The position of the poles, however, is determined by the equatorial bulges; if they are “reshaped” for some reason, the poles shift without any significant change of the momentum. Due to the enormous extend of its oceans, Earth is an inherently unstable planet, so much so that a kick apparently irrelevant can trigger a process that in a very short period, that is instantaneously in geological time, provokes a reshaping of the equatorial bulge, thus making the poles shift permanently. When this happens all the masses on its surface, atmosphere, oceans and continents, are suddenly subjected to tangential forces, thus triggering a global catastrophe and long lasting effects for what concerns climate, volcanism and circulation cells of the mantle.

Experimental Study on Sugarcane Bagasse Pyrolysis in a Hermochemical Processes Pilot Plant

This paper investigates the sugarcane bagasse pyrolysis for bio-oil and biochar production in a pilot plant that was designed to perform the gasification process. After some modifications of changing the temperature of fluidized bed reactor and the catalytic reforming reactor, the fast pyrolysis process was performed at 500–600 °C using a fluidized bed reactor (air flow rate: 20–70 L.min-1) under atmospheric pressure, with sugarcane bagasse feeding (2–3.5 kg.h-1) with particles size less than 1.18 mm. Fluidization tests were performed with air feed (oxidative pyrolysis), to guarantee the fluidization is occurring, finding that the minimum fluidization rate was 22 L.min-1 (minimum velocity of gas: 6.3 cm.s-1). The residence time was 7 seconds (ratio between empty reactor volume by fluidizing gas flow). The highest bio-oil yield of 7.43 wt. % was obtained at 500 °C, with a bagasse flow rate of 3.5 kg.h-1 and 25.93 L.min-1 of air flow rate, and this low yield can be explained by the inefficient heat exchanger used. On the other hand, biochar yield achieved 35.88 wt. % using a temperature of 570 °C, 3.1 kg.h-1 of bagasse flow rate, and 28.26 L.min-1 of air flow rate. Considering this pilot plant has never operated in a pyrolysis mode, these results demonstrate that pyrolysis can be applied to this pilot plant, being versatile for different types of processes with a great potential for biochar and bio-oil production besides the high gas production.

ATMOSFER RUANG DI STUDIO AIR PUTIH @BATUBATA, TANGERANG

Abstrak - Suasana atmosfer ruang yang berbeda antara ruang luar yang dinamis dan beragam, secara gradual menjadi singular dan statis ditemukan pada @Batubata. Hal ini berbeda dengan ruang arsitektur yang hanya dipahami sebagai sebuah hegemoni occulocentrism, yang berfokus hanya pada kajian visual.Studi dilakukan untuk memahami pembentukan atmosfer ruang, dengan memahami elemen fisik-spasial-material yang membentuknya dan sensasi periferal yang tidak sadar, dialami subjek penggunanya. Atmosfer ruang bersifat abstrak dan intangible yang suasananya bisa dirasakan melalui medium ruang pada lingkungan binaan yang sifatnya perlahan (slowness) dan mendorong kesendirian (secluded). Pembelajaran dilakukan melalui dua tahap studi. Tahap pertama untuk memaparkan elemen fisik-spasial-material melalui pembahasan layering dan transparansi, dimensi dan proporsi, density dan emptiness, serta material berdasarkan teori desain spasial Bert Bielefelt. Tahap kedua dilakukan pemaparan sensasi periferal yang dirasakan pengamat saat mengalami ruang- ruang di @Batubata. Sensasi periferal dirasakan simultan menggugah emosi dan imajinasi penggunanya. Pemaparan dilakukan berdasarkan teori yang disampaikan oleh Juhanni Pallasmaa. Pembentukan atmosfer ruang dipahami berdasarkan hasil kesimpulan pada kedua tahap ini.Studi ini merupakan studi terhadap fenomena yang terjadi di dalam ruang arsitektur. Metoda yang digunakan adalah deskriptif kualitatif, data diperoleh dari studi literatur, pengamatan lapangan, wawancara dengan arsitek perencana dan kuisioner kepada subjek pengguna. Penelitian dilakukan dengan meninjau elemen fisik spasial dan material melalui observasi awal, yang diperkaya dengan wawancara dan kuisioner terbuka kepada pengguna ruang.Dari hasil analisis tahap 1 didapat kesimpulan karakter ruang yang secluded, statis dan rapat. Pada analisis tahap 2, dihasilkan pengalaman ruang yang sunyi dan tenang.Dari kedua tahap tersebut, bisa disimpulkan bahwa @Batubata mampu memberikan kesempatan bagi pengunjung untuk merasakan kesendirian (solitude) dan keperlahanan (slowness) untuk mengalami atmosfer melalui sensasi periferal mereka. Perasaan dan suasana hati subjek pengguna selalu memengaruhi pembentukan atmosfer ruang yang bersifat abstrak.

Mechanism of atmospheric organic amines reacted with ozone and implications for the formation of secondary organic aerosols

Organic amines are one of the most important nitrogen-containing compounds in the atmosphere, and their reactions with tropospheric ozone contribute significantly to the formation of secondary organic aerosols (SOA). However, the chemical pathways of their reaction with atmospheric ozone are poorly understood. This study investigates the atmospheric ozonolysis mechanism of two typical organic amines—diethylamine and triethylamine using experimental and theoretical methods. Intermediate results from GC–MS and PTR-TOF-MS analysis confirm the formation of eight and eleven nitrogen- and oxygen-containing products during the ozonolysis of diethylamine and triethylamine, respectively. N-ethylethanimine (56.5% in average) or acetaldehyde (64.9% in average) is formed as the dominant product from the ozonolysis of each organic amine. Ozonolysis pathway results indicate that the conversion to N-ethylethanimine is the dominant pathway for diethylamine ozonolysis. At the same time, triethylamine prefers the initial transformation to diethylamine with the discharge of acetaldehyde and then converts to N-ethylethanimine. Higher SOA mass concentration is obtained from the ozonolysis of triethylamine than diethylamine, probably because the former releases a larger amount of intermediate products, especially acetaldehyde. Our results provide a deep insight into the atmospheric processing of organic amines via ozonolysis and the implications of this mechanism for SOA formation.

Produksi bersih dan model kerjasama sebagai upaya mitigasi emisi gas rumah kaca pada sektor industri

Pemanasan global telah menyita perhatian dunia bahkan akan semakin bertambah besar dimasa yang akan datang mengingat akibat yang ditimbulkannya UNO, melalui program lingkungan UNEP (United Nations Environment Programme) dan Organisasi Meteorologi Dunia (World Meteorological Organization, WMO) membentuk The Intergovernmental Panel on Climate Change (IPCC) pada 1988 untuk meneliti dan menganalisa isu-isu ilmu pengetahuan yang muncul. Makalah ini akan membahas tentang emisi GRK dari empat industri yaitu baja, aluminium, semen dan kimia.Guna mengantisipasi meningkatnya emisi GRK maka keempat industri ini perlu melakukan kerjasama. Model kerjasama apa yang paling tepat juga akan dibahas pada makalah ini.Selanjutnya alternatif solusi yang bisa. Ada beberapa emisi GRK dari sektor industri, mulai dari industri kimia, baja, semen dan alumunium. Dalam Protocol Kyoto, tersedia tiga mekanisme fleksibel dalam upaya pencapaian target penurunan emisi GRK, yaitu Emissions Trading (ET) atau perdagangan emisi antar negara maju, Joint Implementation (JI) atau pelaksanaan penurunan emisi secara bersama sama antar negara maju, dan Clean Development Mechanism (CDM) atau kerjasama antara negara maju dan negara berkembang. Studi ini menyimpulkan bahwa salah satu cara yang strategis untuk melindungi atmosfir adalah dengan cara mengontrol penggunaan sumber daya alam melalui emisi GRK.

Characteristics and Sources of Microbial Aerosols in Urban and Mountainous Areas in Autumn and Winter in Xi'an, China

To explore the bioaerosol composition characteristics and sources in urban areas and mountains, three sample sites were selected in urban (urban, suburban) and southern mountainous areas in Xi'an, and air, soil, and leaf samples were simultaneously collected. The fungi and bacteria community structures at different sampling sites were analyzed through a high-throughput sequencing method, and their spatio-temporal variations were also examined. Moreover, a source track technique was used to identify the source of microorganisms in the air. The results showed that the fungi and bacteria at different sampling sites were significantly different, indicating that the geographical location has a significant influence on the community structure of microorganisms in the air. In winter, more potential fungal pathogens and bacterial pathogens were detected in urban areas with high relative abundance and diversity. In addition, the results showed that the main local source of fungi and bacteria was the leaf surface, of which the contribution rate of bacteria in the air fine particles was up to (55±30)%. This study can provide a scientific basis for understanding the characteristics of microbial pollution in the atmosphere, and for air environment quality evaluation and disease prevention in China.

Pollution characteristics and source analysis of metal and metalloid elements in PM_(2. 5)in two districts of Xi'an City from 2016 to 2018

To investigate the concentration levels and sources of 12 metals and metalloids in PM_(2. 5) in Lianhu district and Yanta district of Xi'an City. From 2016-2018, PM_(2. 5) samples were collected periodically in the monitoring points of the two urban areas of Xi'an City. According to the ministry of environmental protection's "Ambient air and stationary source emission-Determination of metals in ambient particulate matter-Inductively coupled plasma/mass spectrometry"(HJ 657-2013) to determine the content of 12 metals and metalloid elements(Sb, Al, As, Be, Cd, Cr, Hg, Pb, Mn, Ni, Se, Ti). To analyse and evaluate of As, Cd, Pb and Hg according to the annual average reference concentration limit of "Ambient air quality standards"(GB 3095-2012). The main sources of 12 metals and metalloid elements were identified by enrichment factor(EF) and factor analysis. The total qualified rates of As, Cd, Pb and Hg were 46. 89%, 83. 03%, 99. 00% and 100. 00%, respectively, and the difference between the years was not statistically significant(P>0. 05). The average concentration of 12 metals and metalloid elements in PM_(2. 5) for three years was as follows: Al>Pb>Mn>As>Se>Sb>Cr>Cd>Ti>Ni>Hg>Be. The average concentration of As was 10. 10 ng/m~3, which was 1. 68 times exceeding the standard. The average concentration of Cd was 2. 68 ng/m~3, and the average concentration of Pb was 81. 26 ng/m~3. Concentration levels of As, Cd and Pb were on the decline. The EF values of Al, Cr, and Ni were all ≤1, the EF value of As was between 1 and 10. The EF values of Sb, Pb and Ti were all >10, and the EF values of Cd and Se were all >300. The main components of each year from 2016 to 2018 were 2, 2 and 3 respectively. The main component 1 included Pb, As, Cd, Se, Sb and Mn, and the main component 2 included Al, Cr and Ni. In 2018, the main component 3 included Ti(Ti was located in the main component 1 in 2016 and 2017). The sources of pollution of metals and metalloid elements in PM_(2. 5) in the atmosphere of Xi'an City mainly include motor vehicle emissions, coal combustion, industrial pollution and natural particles.

Initial Corrosion Behavior of Carbon Steel and Weathering Steel in Nansha Marine Atmosphere

Initial Corrosion Behavior of Carbon Steel and Weathering Steel in Nansha Marine Atmosphere

FATTY ACID PROFILE AND SENSORY PROPERTIES OF ROE DEER MEAT AFTER MODIFIED ATMOSPHERE STORAGE

The aim of this study was to determine the effect of cold storage (2°C, 7 and 21 days) under vacuum and modified atmosphere (MA) conditions on the fatty acid (FA) profile and sensory properties of the Longissimus thoracis et lumborum from male roe deer. The total content of polyunsaturated FA tended to decrease during storage. Storage conditions had a limited (P>0.05) influence on the FA composition. Vacuum- and MA-packaged meat was characterized by high sensory quality during storage. However, samples packaged in MA composed of 40% CO2+60% N2 had a tendency to higher average scores for taste desirability after the third week of storage.