Grand challenges in the nitrogen cycle

2021 ◽  
Author(s):  
Nicolai Lehnert ◽  
Bradley W. Musselman ◽  
Lance C. Seefeldt

In this Viewpoint, we address limitations within our current understanding of the complex chemistry of the enzymes in the Nitrogen Cycle. Understanding of these chemical processes plays a key role in limiting anthropogenic effects on our environment.

2017 ◽  
Vol 4 (1) ◽  
pp. 83-86
Author(s):  
V. Mazánková ◽  
L. Töröková ◽  
D. Trunec ◽  
F. Krčma ◽  
S. Matejčík ◽  
...  

The exploration of planetary atmosphere is being advanced by the exciting results of the Cassin-Huygens mission to Titan. The complex chemistry revealed in such atmospheres leading to the synthesis of bigger molecules is providing new insights into our understanding of how life on Earth developed. This work extends our previous investigation of nitrogen-methane (N<sub>2</sub>-CH<sub>4</sub>) atmospheric glow discharge for simulation chemical processes in prebiotic atmospheres. In presented experiments 2 % of water vapor were addet to nitrogen-methane gas mixture. Exhaust products of discharge in this gas mixture were in-situ analysed by Fourier Transform Infra Red spectroscopy (FTIR). The major products identified in spectra were: hydrogen cyanide, acetylene and acetonitrile.


1970 ◽  
Vol 5 (2) ◽  
pp. 128-144 ◽  
Author(s):  
Carleton Perrin

For French chemistry the early 1770's were lively years of discovery and controversy. Two neglected areas of research were opened up in 1772 with the publication of the Digressions académiques by Louis-Bernard Guyton de Morveau and with the first knowledge of later British pneumatic chemistry. Guyton's book established the general fact of weight-gain in metals upon calcination, thereby raising the problem of reconciling this gain with simultaneous loss of phlogiston. The spread of pneumatic chemistry, which proceeded rapidly in 1773, stimulated a renewed interest in the nature of air and its part in chemical composition. It was, of course, Antoine Laurent Lavoisier who perceived a relationship between these two developments—one which he believed would revolutionize the current understanding of chemical processes. In 1772 Lavoisier began the series of investigations which culminated in his Opuscules physiques et chimiques (1774), in which he demonstrated that weight-gain in both calcination and combustion is correlated with absorption of an equal weight of air.


1983 ◽  
Vol 45 (5) ◽  
pp. 1633-1645 ◽  
Author(s):  
Clifford N. Dahm ◽  
John A. Baross ◽  
Amelia K. Ward ◽  
Marvin D. Lilley ◽  
James R. Sedell

2018 ◽  
Vol 3 (12) ◽  
Author(s):  
Anthony M. Noce

Abstract In its simplest form, green chemistry may be defined as the design of chemical products and processes that reduce or eliminate the generation of hazardous substances. The brief history of green chemistry is marked with extraordinary creativity and accomplishments in meeting the “triple bottom line” of sustainability in economic, social, and environmental performance. Green chemistry is about redesigning chemical processes from the ground up, and it goes hand in hand with the sustainable practice of chemistry. We need to start at the undergraduate level, and to provide a better foundation in green chemistry and systems thinking if we are to prepare a generation of chemists able to respond to the grand challenges of sustainability.


2019 ◽  
Vol 40 (2) ◽  
pp. 92-103 ◽  
Author(s):  
Janko Međedović ◽  
Goran Knežević

Abstract. Earlier research suggested that militant extremists could have certain aspects of psychopathic and psychotic characteristics. Relying on these studies, we investigated whether the Militant Extremist Mind-Set (MEM) could be explained by psychopathy, sadism, and Disintegration (psychosis proneness), as subclinical manifestations of amoral, antisocial, and psychotic-like traits. In Study 1 (306 undergraduate students), it was shown that sadistic and psychopathic tendencies were related to Proviolence (advocating violence as a means for achieving a goal); psychopathic and disintegrative tendencies were associated to the Vile World (belief in a world as a corrupted and vile place), while Disintegration was the best predictor of Divine Power (relying on supernatural forces as a rationale for extremist acts). In Study 2 (147 male convicts), these relations were largely replicated and broadened by including implicit emotional associations to violence in the study design. Thus, while Proviolence was found to be related to a weakened negative emotional reaction to violent pictures, Vile World was found to be associated with stronger negative emotions as a response to violence. Furthermore, Proviolence was the only MEM factor clearly differentiating the sample of convicts from male students who participated in Study 1. Results help extend current understanding about personal characteristics related to militant extremism.


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