scholarly journals Photo-Oxidation of Ammonia to Molecular Nitrogen in Water under UV, Vis and Sunlight Irradiation

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 975
Author(s):  
Francesco Conte ◽  
Veronica Pellegatta ◽  
Antonio Tripodi ◽  
Gianguido Ramis ◽  
Ilenia Rossetti

Titanium dioxide-based photocatalysts have been used to perform the photo-oxidation of ammonium/ammonia to molecular nitrogen. Different light sources were employed, i.e., UV, LED visible light and natural sunlight, and their performance was compared in order to understand which setup was the most efficient. It was found that under selected conditions, the LED lamp, in combination with silver-promoted TiO2, was able to push the conversion of ammonium toward 48% after 4 h of reaction time. On the other hand, with a more powerful UV lamp, lower conversion was achieved, ca. 40%. Natural sunlight under the same conditions attained more than 38% conversion, but the fluctuation of the reaction conditions remain a very critical issue for the real exploitation of sunlight in water treatment.

2020 ◽  
Vol 24 ◽  
Author(s):  
Bubun Banerjee ◽  
Gurpreet Kaur ◽  
Navdeep Kaur

: Metal-free organocatalysts are becoming an important tool for the sustainable developments of various bioactive heterocycles. On the other hand, during last two decades, calix[n]arenes have been gaining considerable attention due to their wide range of applicability in the field of supramolecular chemistry. Recently, sulfonic acid functionalized calix[n] arenes are being employed as an efficient alternative catalyst for the synthesis of various bioactive scaffolds. In this review we have summarized the catalytic efficiency of p-sulfonic acid calix[n]arenes for the synthesis of diverse biologically promising scaffolds under various reaction conditions. There is no such review available in the literature showing the catalytic applicability of p-sulfonic acid calix[n]arenes. Therefore, we strongly believe that this review will surely attract those researchers who are interested about this fascinating organocatalyst.


Sensor Review ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Tunan Chen ◽  
Fengxiang Ma ◽  
Yue Zhao ◽  
Zhenghai Liao ◽  
Zongjia Qiu ◽  
...  

Purpose This paper aims to establish a photoacoustic detection system for SO2 using UV-LED and testify its feasibility for sensitive measurement. The work in this paper can avoid potential crossover interference in infrared (IR) range and also balance the capability and cost of feasible excitation for photoacoustic detection system. Design/methodology/approach In this experimental work, a cantilever-enhanced–based photoacoustic SO2 detection system using an ultraviolet (UV) LED light source with a light power of 4 mW as the excitation was established. Findings A feasible photoacoustic detection system for SO2 using UV-LED was established. Experimental results demonstrate that the detection limit of the system can reach the level of 0.667 ppm, which can serve as a reference for the application of PAS in insulation fault diagnosis. Originality/value This work investigated the potential of using ultraviolet photoacoustic spectroscopy to detect trace SO2, which provided an ideal replacement of infrared-laser-based detection system. In this paper, a photoacoustic detection system using LED with a low light power was established. Low light power requirement can expand the options of light sources accordingly. In this paper, the absorption characteristics of SO2 in the presented detection system and ultraviolet range were studied. And the detection limit of the presented system was given. Both of which can provide reference to SO2 detection in ambient SF6.


Author(s):  
V. Kozachuk ◽  
M. Sliusarenko

In the article, the authors propose a method for controlling the presence of foreign substances and objects inside the barrel. The problem of surface cleanliness control remains relevant in many areas, ranging from sanitary cleaning to nanoelectronics. In the military sphere, this becomes particularly important during the cleaning of cannon barrels. Both powder combustion products and cartridge cap and bullet shell particles are deposited in the barrel during firing from guns. Under the impact of high temperatures, the bullet particles are partially oxidized and cover the barrel channel with a thin layer of deposit of oxides, which are difficult to dissolve. As a result, the density of the bullet abuting the walls changes. This affects the characteristics of its motion inside the barrel. The accuracy of the shot is reduced, and subsequently the precision and accuracy of shooting in general decreases. The essence of the proposed method consists in the fact that a light source is placed in the bore of the barrel on one side, and an optical device is placed on the other side, with the help of which the presence of foreign substances and objects is monitored. Unlike the known methods, this method is characterized in that several monochrome light sources in addition are placed in turn in the bore of the barrel from the breech part, and in the bore of the barrel from the muzzle part there is equipment for receiving (detecting) monochrome light. Then, obtained monochrome light is analyzed, current value of its defined parameters is determined. At the next stage, parameter values of monochrome light fixed during control are compared with parameter values of reference signatures, which had been obtained before the barrel was put in service. These values are stored in equipment memory. If the values of at least one of the parameters from at least one of the monochrome light sources are found to be inconsistent with the parameters of the reference signatures, the equipment for receiving and analyzing monochrome light gives a signal about the presence of foreign substances and objects in the bore of the barrel.


2021 ◽  
Vol 11 (1) ◽  
pp. 12-23
Author(s):  
Halime Turkkan

With the development of technology and the dominance of the digital world, typography has become a critical issue. Information design systems are considered as one of the significant areas of graphic design and big data provides essential information on data visualization. This research aims to analyse the effects of typographic elements on visualizing data in terms of visual communication, by discussing the value that typography gives to design space. The research discusses randomly selected 10 infographic design samples published in the last six months on google. From the results, 5 designs with typographic concern were more favourable and visually more striking and preferable than the other 5 designs in terms of design disciplines. As in all areas of graphic design, it is argued that the power of typography is an indisputable concept in data visualization, which is seen as a sub-branch of information design. Keywords: data visualization; design; typography, significance, technology


Author(s):  
Dr. B Jishamol

Buckingham Canal bank was an important water - way of old Madras. It has been facing slow death due to many reasons such as encroachments by various constructions like MRTS (The Mass Rapid Transit System is popularly called MRTS), and also the Urban poor, the slum dwellers. The slum dwellers face various problems like, flooding, insanitary conditions, health and socio-economic issues. One of the major issue is the eviction process. In this link, the Elango Street of Govindaswamy Nagar has been allotted by the Tamil Nadu Slum Clearance Board based on G.O.Ms.No 163 Housing (F) Department, Dated 28.02.1973. Elango Street escapes all the natural problems the other slums are facing, but it is expected to be evicted. This critical issue made the researcher to compare Elango Street of Govindaswamy Nagar with the other slums on the banks of Central Buckingham Canal.


Author(s):  
Marta de-Melo-Diogo ◽  
Jorge Tavares ◽  
Ângelo Nunes Luís

Blockchain technology in a clinical trial setting is a valuable asset due to decentralization, immutability, transparency, and traceability features. For this chapter, a literature review was conducted to map the current utilization of blockchain systems in clinical trials, particularly data security managing systems and their characteristics, such as applicability, interests of use, limitations, and issues. The advantages of data security are producing a more transparent and tamper-proof clinical trial by providing accurate, validated data, therefore producing a more reliable and credible clinical trial. On the other hand, data integrity is a critical issue since data obtained from trials are not instantly made public to all participants. Work needs to be done to establish the significant implications in security data when applying blockchain technology in a real-world clinical trial setting and generalized conditions of use to establish its security.


2013 ◽  
Vol 295-298 ◽  
pp. 1209-1214 ◽  
Author(s):  
Si Hang Shan ◽  
Peng Fei Fan ◽  
Yi Xing ◽  
Geng Qiao

Two kinds of vitamin B12 waste water from a pharmaceutical factory were treated separately by methods of combining micro-electrolysis with physiochemical and O3 oxidation. Effects of the reaction conditions on the removal rate of color were investigated. Results showed that the color removal rate of vitamin B12 waste water, which was treated by combined micro-electrolysis and physiochemical treatment reached 71.25%, while the color removal rate of the other waste water which treated by O3 oxidation reached 68.80%. The decolorizing treatment of those different natures of vitamin B12 waste water effectively provides a useful reference for this kind of waste water.


1979 ◽  
Vol 34 (12) ◽  
pp. 1205-1208 ◽  
Author(s):  
K. H. Grumbach

Abstract Two β-Carotene pools were obtained in the chloroplast. It is concluded that one pool is very small like α-carotene and responsible exclusively for the biosynthesis of β-ionone-xanthophylls. The other β-carotene pool is proposed to be the one, that is located close to photosystem I and is involved in photosynthesis as a light protecting agent for chlorophylls against photo-oxidation. Furthermore evidence is given that both β-carotene pools are synthesized by independent biosyn thetic pathways.


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