A submillimeter heterodyne radiometer, developed for astronomical applications, uses an optically pumped laser local oscillator and a quasi-optical Schottky diode mixer. The resultant telescope-mounted system, which has a noise temperature less than 4000 K (double sideband) and high frequency and spatial resolution, has been used to detect the J = 6 --> 5 rotational transition of carbon monoxide at 434 micrometers in the Orion molecular cloud. The measurements, when compared with previous millimeter-wave data, indicate that the broad carbon monoxide emission feature is produced by an optically thin gas whose temperature exceeds 180 K.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1126/science.211.4482.580 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Spatio-temporal analysis of formaldehyde and its association with atmospheric and environmental variables over the Southeast Asian region using satellite data.
Environ Monit Assess
January 2025
Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi, Delhi, 110078, India.
This study investigates the spatio-temporal distribution of formaldehyde (HCHO) over the mainland Southeast Asian region (including Northeast India) from 2019 to 2022 using TROPOMI satellite data. HCHO is a key atmospheric trace gas which is influenced by both natural processes and anthropogenic activities. We analyze HCHO levels in relation to atmospheric species including carbon monoxide (CO), nitrogen dioxide (NO), and environmental factors such as land surface temperature (LST), precipitation (PPT), fire radiative power (FRP), and enhanced vegetation index (EVI).
View Article and Find Full Text PDFJinbei oral liquid for idiopathic pulmonary fibrosis: a randomized placebo-controlled trial.
Sci Rep
January 2025
Department of Respiratory and Critical Care Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, People's Republic of China.
The traditional Chinese medicine compound preparation known as Jinbei Oral Liquid (JBOL) consists of 12 herbs, including Astragalus membranaceus (Fisch.) Bge, Codonopsis pilosula (Franch.) Nannf, et al.
View Article and Find Full Text PDFAmbient Air Pollution and COPD: The Multiethnic Cohort Study.
Ann Am Thorac Soc
January 2025
University of California San Francisco, Department of Epidemiology and Biostatistics, San Francisco, California, United States.
Rationale: Globally, in 2019, chronic obstructive pulmonary disease (COPD) was the third leading cause of death. While tobacco smoking is the predominant risk factor, the role of long-term air pollution exposure in increasing risk of COPD remains unclear. Moreover, there are few studies that have been conducted in racial and ethnic minoritized and socioeconomically diverse populations, while accounting for smoking history and other known risk factors.
View Article and Find Full Text PDFNi Single Atoms/FeN Nanoparticles Supported by N-Doped Carbon Hollow Nanododecahedras with Nanotubes on the Surface for Efficient Electro-Reduction of CO to CO.
Small
January 2025
College of Materials Science and Engineering, Sichuan University, Chengdu, 610065, China.
The transition metal single atoms (SAs)-based catalysts with M-N coordination environment have shown excellent performance in electrocatalytic reduction of CO, and they have received extensive attention in recent years. However, the presence of SAs makes it very difficult to efficiently improve the coordination environment. In this paper, a method of direct high-temperature pyrolysis carbonization of ZIF-8 adsorbed with Ni and Fe ions is reported for the synthesis of Ni SAs and FeN nanoparticles (NPs) supported by the N-doped carbon (NC) hollow nanododecahedras (HNDs) with nanotubes (NTs) on the surface (Ni SAs/FeN NPs@NC-HNDs-NTs).
View Article and Find Full Text PDFRevealing the catalytic oxidation mechanism of CO on α-FeO surfaces: an thermodynamic study.
Phys Chem Chem Phys
January 2025
Institute of Nanomaterials, Faculty of Materials Science, Kim Il Sung University, Ryongnam-Dong, Taesong District, Pyongyang, Democratic People's Republic of Korea.
Significant research efforts have been devoted to improving the efficiency of catalytic carbon monoxide (CO) oxidation over α-FeO-based catalysts, but details of the underlying mechanism are still under debate. Here we apply the thermodynamic method (AITM) within the density functional theory framework to investigate the phase diagram of α-FeO(0001) surfaces with various terminations and the catalytic mechanism of CO oxidation on these surfaces. By extending the conventional AITM to consider the charge state of surface defects, we build the phase diagram of α-FeO(0001) surfaces in relation to the Fermi energy as well as the oxygen chemical potential, which makes it possible to explain the influence of point defects on the surface morphology and to predict the existence of the experimentally observed functional sites such as the ferryl group (FeO) and oxygen vacancies.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!