scholarly journals Observations of Gas-Phase Alkylamines at a Coastal Site in the East Mediterranean Atmosphere

Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1454
Author(s):  
Evangelia Tzitzikalaki ◽  
Nikos Kalivitis ◽  
Maria Kanakidou
Keyword(s):  
Gas Phase ◽  
High Performance ◽  
Animal Husbandry ◽  
Anthropogenic Sources ◽  
Clear Correlation ◽  
East Mediterranean ◽  
Triple Quadrupole Mass Spectrometer ◽  
Nucleation Mode ◽  
Marine Source ◽  
The University

Atmospheric amines are ubiquitous compounds in the atmosphere, having both natural and anthropogenic origin. Recently, they have been identified as important contributors to new particle formation in the atmosphere, but observations of their atmospheric concentrations are scarce. In the present study we introduce the first systematic long-term observations of gas-phase amines measurements in the East Mediterranean atmosphere. Air samples were collected at the Finokalia monitoring station of the University of Crete during a 3.5-year period from January 2013 to July 2016, and analyzed after extraction using a high-performance liquid chromatography triple quadrupole mass spectrometer. The detected alkylamines were the sum of dimethylamine and ethylamine (DMA+EA), trimethylamine (TMA), diethylamine (DEA) and triethylamine (TEA). DMA+EA and TMA were the most abundant alkylamines, with concentrations spanning from the detection limit to 78.0 and 69.8 pptv, and average concentrations of 7.8 ± 12.1 and 7.5 ± 12.4 pptv, respectively. Amines showed pronounced seasonal variability with DMA+EA and TMA concentrations being higher in winter. Statistical analysis of the observations showed different sources for each of the studied amines, except for DMA+ΕA and DEA that appear to have common sources in the region. This analysis points to a marine source of TMA and animal husbandry in the area as a potential source of TEA. None of the alkylamines is correlated with other anthropogenic sources. Furthermore, no clear association was found between the seasonality of NPF events and alkylamines concentrations, while a clear correlation was detected between the seasonality of nucleation mode particle (dp < 25 nm) number concentrations and alkylamine concentrations, indicating that amines may contribute to nucleation mode particles’ production.

Advances in imaging SIMS studies of stained and BrdU-labelled human metaphase chromosomes

1995 ◽  
Vol 53 ◽  
pp. 932-933
Author(s):  
R. Levi-Setti ◽  
J. M. Chabala ◽  
R. Espinosa ◽  
M. M. Le Beau
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Analytical Sensitivity ◽  
Metaphase Chromosomes ◽  
Banding Patterns ◽  
Sector Mass Spectrometer ◽  
Staining Methods ◽  
The University ◽  
Secondary Ion ◽  
Better Than

We have shown previously that isotope-labelled nucleotides in human metaphase chromosomes can be detected and mapped by imaging secondary ion mass spectrometry (SIMS), using the University of Chicago high resolution scanning ion microprobe (UC SIM). These early studies, conducted with BrdU- and 14C-thymidine-labelled chromosomes via detection of the Br and 28CN- (14C14N-> labelcarrying signals, provided some evidence for the condensation of the label into banding patterns along the chromatids (SIMS bands) reminiscent of the well known Q- and G-bands obtained by conventional staining methods for optical microscopy. The potential of this technique has been greatly enhanced by the recent upgrade of the UC SIM, now coupled to a high performance magnetic sector mass spectrometer in lieu of the previous RF quadrupole mass filter. The high transmission of the new spectrometer improves the SIMS analytical sensitivity of the microprobe better than a hundredfold, overcoming most of the previous imaging limitations resulting from low count statistics.

scholarly journals Numerical Evaluation of a HVAC System Based on a High-Performance Heat Transfer Fluid

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3298
Author(s):  
Gianpiero Colangelo ◽  
Brenda Raho ◽  
Marco Milanese ◽  
Arturo de Risi
Keyword(s):  
Heat Transfer ◽  
High Performance ◽  
Cooling System ◽  
Electrical Energy ◽  
Simulation Software ◽  
Heat Transfer Fluid ◽  
Hvac System ◽  
Dynamic Simulations ◽  
Heating And Cooling ◽  
The University

Nanofluids have great potential to improve the heat transfer properties of liquids, as demonstrated by recent studies. This paper presents a novel idea of utilizing nanofluid. It analyzes the performance of a HVAC (Heating Ventilation Air Conditioning) system using a high-performance heat transfer fluid (water-glycol nanofluid with nanoparticles of Al2O3), in the university campus of Lecce, Italy. The work describes the dynamic model of the building and its heating and cooling system, realized through the simulation software TRNSYS 17. The use of heat transfer fluid inseminated by nanoparticles in a real HVAC system is an innovative application that is difficult to find in the scientific literature so far. This work focuses on comparing the efficiency of the system working with a traditional water-glycol mixture with the same system that uses Al2O3-nanofluid. The results obtained by means of the dynamic simulations have confirmed what theoretically assumed, indicating the working conditions of the HVAC system that lead to lower operating costs and higher COP and EER, guaranteeing the optimal conditions of thermo-hygrometric comfort inside the building. Finally, the results showed that the use of a nanofluid based on water-glycol mixture and alumina increases the efficiency about 10% and at the same time reduces the electrical energy consumption of the HVAC system.

Learnings from the Field Implementation of a Novel Ultra-High Performance Concrete Beam End Repair on a Corroded Steel Girder Bridge in Connecticut

2021 ◽  
pp. 036119812110041
Author(s):  
Alexandra Hain ◽  
Arash E. Zaghi
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Implementation Process ◽  
Lessons Learned ◽  
Load Path ◽  
Ultra High Performance Concrete ◽  
Steel Girder Bridge ◽  
Aging Steel ◽  
Girder Bridge ◽  
The University

Corrosion at steel beam ends is one of the most pressing challenges in the maintenance of aging bridges. To tackle this challenge, the Connecticut Department of Transportation (DOT) has partnered with the University of Connecticut to develop a repair method that benefits from the superior mechanical and durability characteristics of ultra-high performance concrete (UHPC) material. The repair involves welding shear studs to the intact portions of the web and encasing the beam end with UHPC. This provides an alternate load path for bearing forces that bypasses the corroded regions of the beam. The structural viability of the repair has been extensively proven through small- and full-scale experiments and comprehensive finite element simulations. Connecticut DOT implemented the repair for the first time in the field on a heavily trafficked four-span bridge in 2019. The UHPC beam end repair was chosen because of the access constraints and geometric complexities of the bridge that limited the viable repair options. Four of the repaired beam ends were fully instrumented to collect data on the performance of the repaired locations before casting, during curing, and for approximately 6 months following the application of the repair. This paper provides an overview of the successful repair implementation and presents the lessons learned during construction. Select data from the monitored beam ends are presented. It is expected that this information will provide engineers with a better understanding of the repair implementation process, and thus provide an additional repair option for states to enhance the safety of aging steel bridges.

scholarly journals Exergy As a Measure of Sustainable Retrofitting of Buildings

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3139 ◽  
Author(s):  
Carlos Fernández Bandera ◽  
Ana Muñoz Mardones ◽  
Hu Du ◽  
Juan Echevarría Trueba ◽  
Germán Ramos Ruiz
Keyword(s):  
High Performance ◽  
Exergy Analysis ◽  
Local Contexts ◽  
Primary Selection ◽  
Optimization Methodology ◽  
The One ◽  
Reference Environment ◽  
Architectural Characteristics ◽  
The University

This study presents a novel optimization methodology for choosing optimal building retrofitting strategies based on the concept of exergy analysis. The study demonstrates that the building exergy analysis may open new opportunities in the design of an optimal retrofit solution despite being a theoretical approach based on the high performance of a Carnot reverse cycle. This exergy-based solution is different from the one selected through traditional efficient retrofits where minimizing energy consumption is the primary selection criteria. The new solution connects the building with the reference environment, which acts as “an unlimited sink or unlimited sources of energy”, and it adapts the building to maximize the intake of energy resources from the reference environment. The building hosting the School of Architecture at the University of Navarra has been chosen as the case study building. The unique architectural appearance and bespoke architectural characteristics of the building limit the choices of retrofitting solutions; therefore, retrofitting solutions on the façade, roof, roof skylight and windows are considered in multi-objective optimization using the jEPlus package. It is remarkable that different retrofitting solutions have been obtained for energy-driven and exergy-driven optimization, respectively. Considering the local contexts and all possible reference environments for the building, three “unlimited sinks or unlimited sources of energy” are selected for the case study building to explore exergy-driven optimization: the external air, the ground in the surrounding area and the nearby river. The evidence shows that no matter which reference environment is chosen, an identical envelope retrofitting solution has been obtained.

scholarly journals UHPLC-QQQ-MS/MS assay for quantification of dianthrones as potential toxic markers of Polygonum multiflorum Thunb: Application to the standardization of TCMs with endogenous toxicity

2021 ◽  
Author(s):  
Jian-Bo Yang ◽  
Yun-Fei Song ◽  
Yue Liu ◽  
Hui-Yu Gao ◽  
Qi Wang ◽  
...  
Keyword(s):  
High Performance ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
Triple Quadrupole ◽  
Quadrupole Mass ◽  
Polygonum Multiflorum ◽  
Triple Quadrupole Mass Spectrometer ◽  
Benefit Risk Assessment ◽  
Heparg Cells

Abstract Background: The raw and processed roots of Polygonum multiflorum Thunb (PM) are commonly used in clinical practice to treat diverse diseases; however, the reports of hepatotoxicity induced by Polygoni Multiflori Radix (PMR) and Polygoni Multiflori Radix Praeparata (PMRP) have emerged worldwide. Thus, it is necessary for researcher to explore the methods to improve its quality standards and further ensure its quality and treatment effect.Methods: In the present study, an ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QQQ- MS/MS) method has been optimized and validated for the determination of dianthrones in PMR and PMRP, using bianthronyl as the internal standard. Chromatographic separation with a gradient mobile phase (A: acetonitrile and B: water containing 0.1% formic acid (v/v)) at a flow rate of 0.25 mL/min was achieved on a Waters Acquilty UPLC BEH b) C18 column (2.1 mm × 50 mm, 1.7 µm). A triple quadrupole mass spectrometer (TQMS) was operated in negative ionization mode with multiple reaction monitoring for the quantitative analysis of six dianthrones. Meanwhile, compounds 5 and 6 were further evaluated for cytotoxicity of HepaRG cells by CCK8 assay.Results: The UHPLC-QQQ-MS/MS method was first developed to simultaneous determination of six dianthrones in PMR and PMRP, namely polygonumnolides C1–C4 (1–4), trans-emodin dianthrones (5), and cis-emodin dianthrones (6). The contents of 1~6 in 90 batches of PMR were in the range of 0.027-19.04, 0.022-13.86, 0.073 -15.53, 0.034 -23.35, 0.38-83.67 and 0.29 -67.00 µg/g, respectively. The contents of 1~6 in 86 batches of commercial PMRP were in the range of 0.020-13.03, 0.051-8.94, 0.022-7.23, 0.030 -12.75, 0.098-28.54 and 0.14-27.79 µg/g, respectively. The six dianthrones were almost completely gone after reasonable processing for 24 h. Meanwhile, compounds 5 and 6 showed the inhibitory activity against HepaRG cells with the IC50 values of 10.98 and 15.45 μM, respectively. Furthermore, a systematic five-step strategy to realize the standardization of TCMs with endogenous toxicity is proposed for the first time, involving the establishment of determination methods, determination of the toxic markers, the standardization of processing method, the development of limit standards and benefit-risk assessment.Conclusion: The results of cytotoxicity evaluation of dianthrone indicated that trans-emodin dianthrones (5) and cis-emodin dianthrones (6) could be selected as the toxic markers of PMRP. Taking PMR and PMRP for example, we hope this study provided insight into the standardization and internationalization of endogenous toxic TCMs, with the main purpose of improving public health by scientifically using TCMs to treat diverse complex diseases in future.

scholarly journals PROJECT MANAGEMENT AS A TOOL FOR DEVELOPMENT ENGINEERING CENTER, BASED AT THE UNIVERSITY

2016 ◽  
Vol 2 (1) ◽  
pp. 240-244
Author(s):  
Малыхина ◽  
Irina Malykhina ◽  
Брежнев ◽  
Aleksey Brezhnev
Keyword(s):  
Project Management ◽  
High Performance ◽  
Building Materials ◽  
Innovative Development ◽  
Research And Innovation ◽  
Steady Growth ◽  
Scientific Results ◽  
The University ◽  
Development Engineering ◽  
Difficult Times

Today, the domestic economy is going through difficult times associated with the instability of the geopolitical situation in the world, a strengthening of the sanctions policy of Western countries to-wards the Russian Federation, limited access to foreign investment and other factors that directly affect the speed and quality of economic development of the state. However, Russia today is on the path of innovative development, so the generation and usage in industry innovation is a priority. Recognition of necessity of innovative development of Russia determines the importance of improving and obtaining good results in such a relatively young activities for our country as project management and engineering. In this paper, the influence of project management as a form of innovative management in the development of the engineering centre, based at the University. Steady growth in demand for engineering services, which contribute to qualitative and effective implemen-tation of the latest technological solutions in production, largely due to the significant complexity of scientific results in scientific, research and innovation. Therefore, the use of the principles and methods of project management creates the conditions for high performance implementation of innovation projects, which include the creation and development of engineering centers, including in the field of building materials industry.

scholarly journals Preparation of isocyanates by carbamates thermolysis on the example of butyl isocyanate

2019 ◽  
Vol 58 (4) ◽  
pp. 40-47
Author(s):  
Ratmir R. Dashkin ◽  
◽  
Dmitry A. Gordeev ◽  
Khusrav Kh. Gafurov ◽  
Sergey N. Mantrov ◽  
...  
Keyword(s):  
Gas Phase ◽  
High Performance ◽  
Gas Flow ◽  
Flow Reactor ◽  
Packed Column ◽  
Biologically Active ◽  
Dibutyltin Dilaurate ◽  
Reaction Products ◽  
Uv Detector ◽  
Laboratory Setup

Butyl isocyanate is widely distributed as a precursor for the production of a number of biologically active substances: fungicides, preservatives, insecticides, personal care products, etc. Nowadays, there are a number of methods for the preparation of isocyanates, which can be divided into liquid phase and gas phase. One of the perspective methods for the production of isocyanates is the thermolysis of carbamate and/or the actions of various reaction activating agents, accompanied by the elimination of alcohol, but this process is reversible, which greatly complicates its use in industry. The paper presents the results of studies of non-catalytic thermal decomposition of N-alkylcarbamates with the formation of alkylisocyanates on the example of butylisocyanate in the gas phase, flow reactor in a wide temperature range (200 to 450 °C). In addition, a series of experiments was carried out using a catalyst, dibutyltin dilaurate, in order to reduce the thermolysis temperature and increase the yield of the final product. To implement the isocyanate production process, an experimental laboratory setup, consisting of a gas flow meter (argon) regulator, a packed column (for heating) and a sorption solution tank, was developed and tested. The thermolysis of N-n-butylcarbamate was carried out in two variations: the preparation of an individual n-butylisocyanate and the passage of reaction products through a sorption solution linking the n-butyl isocyanate to N-n-butyl-N '-(1-phenylethyl)urea, which allows to estimate the yield of the target n-butylisocyanate without additional losses. The analysis of the obtained substances was carried out by high performance liquid chromatography with a UV detector (target product) and a mass detector (analysis of by-products). According to the results of research, a modification of the laboratory facility was proposed, as well as n-butylisocyanate was obtained with a yield of 49% on the basis of a new technique.

scholarly journals Back-end porting of FT_MX based on LLVM compilation architecture

2021 ◽  
Vol 336 ◽  
pp. 04018
Author(s):  
Ping Deng ◽  
Xiaolong Zhu ◽  
Haiyan Sun ◽  
Yi Ren
Keyword(s):  
Open Source ◽  
High Performance ◽  
Instruction Set ◽  
University Of Illinois ◽  
Specific Process ◽  
Defense Technology ◽  
Migration Mechanism ◽  
National University ◽  
Compiler Framework ◽  
The University

The processor FT_MX is a high-performance chip independently developed by the National University of Defense Technology, with an innovative architecture and instruction set. LLVM architecture is a widely used and efficient open source compiler framework initiated by the University of Illinois. This paper introduces the basic architecture and functions of LLVM, analyzes the back-end migration mechanism of the architecture in detail, and gives the specific process of implementing FT_MX back-end migration, and realizes the support of LLVM architecture to the back-end of FT_MX processor.

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