Identification and composition of conformational isomers and their cations in crotonaldehyde by VUV-MATI spectroscopy

2018 ◽  
Vol 20 (42) ◽  
pp. 27162-27168 ◽  
Author(s):  
Sung Man Park ◽  
Hong Lae Kim ◽  
Chan Ho Kwon

Composition of the crotonaldehyde sample at ambient temperature was determined as 93.0%, 3.4%, 3.4%, and 0.2% for the tt-/tc-/ct-/cc-conformers, respectively, for the first time.

2021 ◽  
pp. 074873042110342
Author(s):  
Daniel W. Hart ◽  
Barry van Jaarsveld ◽  
Kiara G. Lasch ◽  
Kerryn L. Grenfell ◽  
Maria K. Oosthuizen ◽  
...  

Mammals have evolved circadian rhythms in internal biological processes and behaviors, such as locomotor activity (LA), to synchronize to the environmental conditions they experience. Photic entrainment of LA has been well established; however, non-photic entrainment, such as ambient temperature ( Ta), has received much less attention. To address this dearth of knowledge, we exposed two subterranean endothermic-homeothermic African mole-rat species, the solitary Cape mole-rat ( Georychus capensis [GC]) and social Mahali mole-rat ( Cryptomys hottentotus mahali [CHM]), to varying Ta cycles in the absence of light. We showed that the LA rhythms of these two species entrain to Ta cycles and that the majority of LA occurred during the coolest 12-h period. LA confined to the coolest Ta periods may be the direct consequence of the poor heat dissipation abilities of African mole-rats brought about by physiological and ecological constraints. Recently, it has been hypothesized that Ta is only a strong zeitgeber for circadian rhythms in species whose thermoregulatory abilities are sensitive to changes in Ta (i.e., heterotherms and ectotherms), which previously has excluded endothermic-homeothermic mammals. However, this study demonstrates that Ta is a strong zeitgeber or entrainer for circadian rhythms of LA in subterranean endothermic-homeothermic mammals as a consequence of their sensitivity to changes in Ta brought about by their poor heat dissipation abilities. This study reinforces the intimate link between circadian rhythms and thermoregulation and conclusively, for the first time, provides evidence that Ta is a strong zeitgeber for endothermic-homeothermic mammals.


2021 ◽  
Author(s):  
Hanbang Liu ◽  
Danhua Yuan ◽  
Liping Yang ◽  
Jiacheng Xing ◽  
Shu Zeng ◽  
...  

The traditional zeolites used in air separation are generally N2-selective adsorbents. It was found for the first time that the O2/N2 adsorption selectivity can be reversed by directly decorating the...


2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
G. B. Lebron ◽  
T. L. Tan

The integrated band intensities of ethylene (12C2H4) in the 640–3260 cm−1 region were determined by Fourier transform infrared (FTIR) spectroscopy. The infrared absorbance spectra of the ν7 and ν10, ν12, ν7+ν8, ν6+ν10, v11, and ν9 and ν2+ν12 bands of ethylene recorded at a resolution of 0.5 cm−1 were measured at an ambient temperature of 296 K at various vapor pressures ranging from 3×10−5 to 1×10−3 atm to obtain respective Beer-Lambert's law plots. The measured integrated band intensities in cm−1/cm atm were S(ν9andν2+ν12)=112.20±0.24, S(ν11)=55.35±0.14, S(ν12)=41.22±0.30, and S(ν7andν10)=328.66±16.55. In addition, the measured infrared band intensities of the ν7+ν8 and ν6+ν10 combination bands of ethylene are reported for the first time: S(ν7+ν8)=21.701±0.028 cm−1/cm atm and S(ν6+ν10)=2.568±0.025 cm−1/cm atm.


RSC Advances ◽  
2016 ◽  
Vol 6 (99) ◽  
pp. 96914-96917 ◽  
Author(s):  
Ming Chen ◽  
Shuanglong Wang

A one-step synthesis of PMDA–ODA polyimide at ambient temperature was reported for the first time, in which a polyimidization reaction was rapidly accomplished in 99% yield in an imidazolium-based ionic liquid containing a non-nucleophilic base.


2014 ◽  
Vol 7 (10) ◽  
pp. 3352-3361 ◽  
Author(s):  
Liyu Jin ◽  
Patrick C. Howlett ◽  
Jennifer M. Pringle ◽  
Judith Janikowski ◽  
Michel Armand ◽  
...  

For the first time, practical lithium cell performance is achieved at ambient temperature with an organic ionic plastic crystal solid electrolyte.


Synthesis ◽  
2018 ◽  
Vol 50 (10) ◽  
pp. 2124-2130 ◽  
Author(s):  
Fariba Rahmani ◽  
Ali Darehkordi

An approach for the synthesis of 4-amino-2-(trifluoromethyl)quinolines via the intramolecular Friedel–Crafts reaction of 2-(1-(arylamino)-2,2,2-trifluoroethylidene)malononitrile derivatives is reported. This simple protocol provides a wide variety of 4-amino-2-(trifluoromethyl)quinolines in good to excellent yields, without any purification. Furthermore, the 2-(1-(arylamino)-2,2,2-trifluoroethylidene) malononitrile derivatives used in this project have been synthesized by the reaction of N-aryl-2,2,2-trifluoroacetimidoyl chlorides and malononitrile at ambient temperature and under microwave irradiation in excellent yields, for the first time.


2015 ◽  
Vol 44 (40) ◽  
pp. 17767-17773 ◽  
Author(s):  
Woormileela Sinha ◽  
Luca Ravotto ◽  
Paola Ceroni ◽  
Sanjib Kar

The observed phosphorescence of the studied Ir(iii)corroles at ambient temperature appears at much longer wavelengths than the previously reported Ir(iii) porphyrin/corrole derivatives. Efficiencies of these compounds in the generation of singlet oxygen are also studied for the first time.


RSC Advances ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 3686-3694
Author(s):  
Sazia Sultana ◽  
Md. Sahadat Hossain ◽  
Monika Mahmud ◽  
Mashrafi Bin Mobarak ◽  
Md Humayun Kabir ◽  
...  

Hap has been developed from eggshell by UV-irradiation for the first time. The negligible cytotoxicity and the efficient delivery of a therapeutic level of ciprofloxacin as well as bioactivity of this UV- Hap supports its use in biomedical fields.


2019 ◽  
Vol 9 (2) ◽  
pp. 3853-3859

Pharmaceuticals have turned in to a major class of contaminants due to their widespread usage and known biological effects. Rifampin is known as an antibiotic with a strong red color. It is used in the treatment of many infectious, especially tuberculosis. If it is used in subtherapeutic concentrations, it can lead to drug resistance in the microbial population. Thus, it is essential to remove its low concentrations from the wastewater to inhibit resistance in a pathogenic microorganism and save its effectiveness against tuberculosis. In the present research, the “Oxidation process by metallic catalysts” method, which consisted of zinc and copper, was employed for the first time in order to remove Rifampin from pharmaceutical wastewater. Variables including the total amount of zinc and copper catalysts, the ratio of the catalysts, duration of the reaction, rotation rate, temperature, and the pH considered and evaluated. It revealed that 0.154 mL of the total amount of the mixture of zinc and copper at the ratio of 70:30 in 100 ml of 40-ppm Rifampin solution, in the neutral pH and at ambient temperature (around 25ºc) and rotation rate, could decrease the concentration of Rifampin to 1 ppm after 120 minutes. The catalysts could be used many times in order to remove the Rifampin from fresh wastewater. It was also shown that 96.4% of Rifampin could be removed from handmade Rifampin solutions and actual wastewater with 70% zinc and 30% copper in 600 rpm, the neutral pH, and the ambient temperature for 120 minutes. The catalysts could be used repeatedly to remove the Rifampin from fresh wastewater.


2009 ◽  
Vol 5 (6) ◽  
pp. 739-742 ◽  
Author(s):  
Marcel E. Visser ◽  
Juan José Sanz

Avian timing of reproduction is strongly affected by ambient temperature. Here we show that there is an additional effect of sunspots on laying date, from five long-term population studies of great and blue tits ( Parus major and Cyanistes caeruleus ), demonstrating for the first time that solar activity not only has an effect on population numbers but that it also affects the timing of animal behaviour. This effect is statistically independent of ambient temperature. In years with few sunspots, birds initiate laying late while they are often early in years with many sunspots. The sunspot effect may be owing to a crucial difference between the method of temperature measurements by meteorological stations (in the shade) and the temperatures experienced by the birds. A better understanding of the impact of all the thermal components of weather on the phenology of ecosystems is essential when predicting their responses to climate change.


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