formation processes
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2022 ◽  
Author(s):  
Jingnan Shi ◽  
Juan Hong ◽  
Nan Ma ◽  
Qingwei Luo ◽  
Yao He ◽  
...  

Abstract. Atmospheric processes, including both primary emissions and secondary formation, may exert complex effects on aerosol hygroscopicity, which is of significant importance in understanding and quantifying the effect of aerosols on climate and human health. In order to explore the influence of local emissions and secondary formation processes on aerosol hygroscopicity, we investigated the hygroscopic properties of submicron aerosol particles at a rural site in the North China Plain (NCP) in winter 2018. This was conducted by simultaneous measurements of aerosol hygroscopicity and chemical composition, using a self-assembled hygroscopic tandem differential mobility analyzer (HTDMA) and a capture-vaporizer time-of-flight aerosol chemical speciation monitor (CV-ToF-ACSM). The hygroscopicity results showed that the particles during the entire campaign were mainly externally mixed, with a more hygroscopic (MH) mode and a less hygroscopic (LH) particles mode. The mean hygroscopicity parameter values (κmean) derived from hygroscopicity measurements for particles at 60, 100, 150, and 200 nm were 0.16, 0.18, 0.16, and 0.15, respectively. During this study, we classified two distinct episodes with different RH/T conditions, indicative of different primary emissions and secondary formation processes. It was observed that aerosols at all measured sizes were more hygroscopic under the high RH (HRH) episode than those under the low RH (LRH) episode. During the LRH, κ decreased with increasing particle size, which may be explained by the enhanced domestic heating at low temperature, causing large emissions of non- or less-hygroscopic primary aerosols. This is particularly obvious for 200 nm particles, with a dominant number fraction (> 50 %) of LH mode particles. Using O : C-dependent hygroscopic parameters of secondary organic compounds (κSOA), closure analysis between the HTDMA_measured κ and the ACSM_derived κ was carried out. The results showed that κSOA under the LRH episode was less sensitive to the changes in organic oxidation level, while κSOA under the HRH had a relatively stronger dependency on the organic O : C. This feature suggests that the different sources and aerosol evolution processes, partly resulting from the variation in atmospheric RH/T conditions, may lead to significant changes in aerosol chemical composition, which will further influence their corresponding physical properties.


The Analyst ◽  
2022 ◽  
Author(s):  
Nicole M. Ralbovsky ◽  
Randal J. Soukup ◽  
Justin P. Lomont ◽  
Mackenzie L. Lauro ◽  
Amanda Gulasarian ◽  
...  

Process analytical technology was used to monitor formation of a stable emulsion product, with results providing improved understanding of emulsion-based vaccine adjuvant formation processes.


2022 ◽  
pp. 413-429
Author(s):  
Fateme Etebari ◽  
Yasaman Enjavi ◽  
Mohammad Amin Sedghamiz ◽  
Mohammad Reza Rahimpour

2021 ◽  
Vol 49 (4) ◽  
pp. 136-161
Author(s):  
E. V. Ivanova ◽  
O. V. Levchenko ◽  
E. A. Ovsepyan ◽  
D. G. Borisov ◽  
T. F. Zinger

On August 6, 2021, the chief researcher of the IO RAS, Doctor of Geological and Mineralogical Sciences, Professor Ivar Oskarovich Murdmaa turned 90 years old. The main focus of I.O. Murdmaa is the study of bottom sediments of seas and oceans, their lithology, mineralogy, deposition processes, facies and formations, the theory of oceanic sedimentogenesis. He first distinguished marine volcanoterrigenous sediments and described the facies variability of modern sediments of island arcs. Ivar Murdmaa is known for his studies in mineralogy of oceanic sediments, processes of pelagic sedimentogenesis and associated iron-manganese nodules formation. Studying sediment formation in rift zones of mid-ocean ridges, he identified a new genetic type of sediments named edaphogeonus sediments, elaborated mineralogical criteria for their recognition and formation processes. In recent years I.O. Murdmaa is actively developing the theoretical concept of "sedimentosphere", paying special attention to a new direction – the study of the erosion-accumulative activity of bottom currents and the formation of contourites.


2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Seiji Kadowaki ◽  
Toru Tamura ◽  
Risako Kida ◽  
Takayuki Omori ◽  
Lisa A. Maher ◽  
...  

AbstractThe Initial Upper Paleolithic (IUP) is a key chrono-cultural concept in our understanding of the cultural and population dynamics at the transition from the Middle Paleolithic to Upper Paleolithic period. This paper presents technological and chronological analyses of lithic assemblages from a rockshelter site at Tor Fawaz in the Jebel Qalkha area, southern Jordan, to provide accurate dating and detailed recognition of the IUP variability in the Levant. We present integrated micromorphological, phytolith, and dung spherulite analyses to evaluate formation and postdepositional processes of archaeological remains through high-resolution micro-contextual studies. As a result, the Tor Fawaz assemblages show general similarity to those of Boker Tachtit Level 4, Tor Sadaf A–B, and Wadi Aghar C–D1 that represent the late phase of the IUP in the southern Levant. Based on the detailed recognition of site-formation processes, we suggest ca. 45–36 ka as the age of IUP occupations at Tor Fawaz. More specifically, the IUP occupations at Tor Fawaz and Wadi Aghar, a nearby IUP site in the same area, may represent slightly different phases that show a lithic technological trend paralleling the IUP sequence at Tor Sadaf in southern Jordan, and possibly post-date Boker Tachtit Level 4. We also discuss the issue of partial chronological overlap between the late IUP and the Ahmarian and also argue for the geographically different trends in cultural changes from the late IUP to the Ahmarian.


2021 ◽  
Vol 924 (1) ◽  
pp. L1
Author(s):  
Chris Lintott ◽  
Michele T. Bannister ◽  
J. Ted Mackereth

Abstract Planetesimals inevitably bear the signatures of their natal environment, preserving in their composition a record of the metallicity of their system’s original gas and dust, albeit one altered by the formation processes. When planetesimals are dispersed from their system of origin, this record is carried with them. As each star is likely to contribute at least 1012 interstellar objects (ISOs), the Galaxy’s drifting population of ISOs provides an overview of the properties of its stellar population through time. Using the EAGLE cosmological simulations and models of protoplanetary formation, our modeling predicts an ISO population with a bimodal distribution in their water mass fraction: objects formed in low-metallicity, typically older, systems have a higher water fraction than their counterparts formed in high-metallicity protoplanetary disks, and these water-rich objects comprise the majority of the population. Both detected ISOs seem to belong to the lower water fraction population; these results suggest they come from recently formed systems. We show that the population of ISOs in galaxies with different star formation histories will have different proportions of objects with high and low water fractions. This work suggests that it is possible that the upcoming Vera C. Rubin Observatory Legacy Survey of Space and Time will detect a large enough population of ISOs to place useful constraints on models of protoplanetary disks, as well as galactic structure and evolution.


Author(s):  
O. G. Litvinova

One of the fundamental urban planning tasks is currently a study of the settlement system properties. In Russian and foreign historical and urban planning science, settlement is studied according to the hierarchical location of settlements. Small and medium-sized settlements are considered as elementary lower units of large cities, their structure and formation processes are not studied. Accordingly, they are rarely considered in elaborating strategic programs of the regional development. The paper proposes the urban retrospective method, which provides a deep and large-scale analysis of the settlement system in the coastal area of the Angara River.Research is based on the cartographic sources developed by governmental institutions whose the activity depends on statistical data. Here belong Ministry of Internal Affairs, Ministry of Agriculture, Ministry of Railways. The comparative analysis of the sources provides modeling and identification of the settlement system with respect to small settlements in the coastal area of the Angara River in different periods. Significant results include the quantitative data on small settlements, since they are not interesting to urban planners of today.


2021 ◽  
Vol 4 (12) ◽  
pp. 158-163
Author(s):  
Nurhidayati Tazar ◽  
Ichwan Suyudi

  Pageant lovers (PLs) in Indonesia use special registers in communicating with each other in their group when discussing pageants on their Instagram accounts. This study aims to find out what types of word-formation processes are found in the register of pageant lovers (PLs) in Indonesia and explain the meaning of that register and how it is translated into English. The data in this study are all words, phrases and sentences, as well as PLs conversational dialogues taken from captions and comments on several PLs Instagram accounts in Indonesia. The research method used in this research is the descriptive qualitative method. The data is analyzed through linguistic characteristics to examine the types of word-formation processes and translate them into English from the data collected. The results of the study show that the PL register in Indonesia has types of word formation, namely (1) Blending: boti, natdir, gercep, gaje, gece etc. (2) Clipping: unfoll-unfollow, parno-paranoid, etc. (3) Acronym: OMG, etc. (4) Coinage: deseu, deswita, alemong, keron, gorjes, alemong, pewong, mekiwati, kenti, buleleng, centong, bensiyong, udin, adindut, luk laik, etc. (5) reduplication: merong-merong, lobi-lobi, jor-joran, henpik-henpik, kaleng-kaleng etc. (6) Abbreviation: PHP, IDL, MU, MS, MGI, MW etc. (7) Compounding: swimsuit, catwalk, etc.


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