THE MERCURY PHOTOSENSITIZED REACTIONS OF BENZENE AT HIGH TEMPERATURES

1951 ◽  
Vol 29 (3) ◽  
pp. 233-242 ◽  
Author(s):  
E. J. Y. Scott ◽  
E. W. R. Steacie
Keyword(s):  
High Temperatures ◽  
Room Temperature ◽  
Main Product ◽  
Main Reaction ◽  
Kcal Mole ◽  
Detailed Mechanism ◽  
Maximum Value ◽  
Secondary Reactions

An investigation has been made of the mercury photosensitized decomposition of benzene at high temperatures. Practically no reaction occurs at room temperature. At higher temperatures the main product is diphenyl although even at 400°C. the maximum value of [Formula: see text] is 0.1. Ediphenyl has been found to be 13 kcal. mole−1. There is evidence that an activated molecule mechanism occurs. The secondary reactions are complex and it is not possible to arrive at a detailed mechanism, but the probable main reaction steps have been pointed out.

REACTION OF OXYGEN ATOMS WITH BENZENE

1961 ◽  
Vol 39 (12) ◽  
pp. 2436-2443 ◽  
Author(s):  
G. Boocock ◽  
R. J. Cvetanović
Keyword(s):  
Activation Energy ◽  
Carbon Monoxide ◽  
Room Temperature ◽  
Main Reaction ◽  
Main Reaction Product ◽  
Kcal Mole ◽  
Volatile Material ◽  
Formed Adduct ◽  
Decomposition Of Nitrous Oxide ◽  
Oxygen Atoms

The reaction of benzene with oxygen atoms produced by mercury photosensitized decomposition of nitrous oxide has been studied in a circulating system at room temperature. The main reaction product is a non-volatile material probably largely aldehydic in character. This is tentatively assumed to result from the rearrangement and polymerization of the initially formed adduct. Smaller amounts of phenol and carbon monoxide are also formed. The rate of formation of carbon monoxide decreases with increasing pressure, suggesting an energy-rich precursor.Oxygen atoms react with benzene much more slowly than with olefines. At 120° cyclopentene reacts about 150 times more quickly than benzene. The activation energy of the reaction of oxygen atoms with benzene has been estimated at 4.6 to 4.9 kcal/mole, with an uncertainty of about 0.7 kcal/mole.

scholarly journals S235JRC+C Steel Response Analysis Subjected to Uniaxial Stress Tests in the Area of High Temperatures and Material Fatigue

2021 ◽  
Vol 13 (10) ◽  
pp. 5675
Author(s):  
Josip Brnic ◽  
Marino Brcic ◽  
Sebastian Balos ◽  
Goran Vukelic ◽  
Sanjin Krscanski ◽  
...  
Keyword(s):  
High Temperatures ◽  
Room Temperature ◽  
Uniaxial Stress ◽  
Fatigue Tests ◽  
Experimental Investigations ◽  
Response Analysis ◽  
Stress Tests ◽  
Staircase Method ◽  
Mechanical Fatigue ◽  
Proper Material

Knowledge of the properties and behavior of materials under certain working conditions is the basis for the selection of the proper material for the design of a new structure. This paper deals with experimental investigations of the mechanical properties of unalloyed high quality steel S235JRC + C (1.0122) and its behavior under conditions of high temperatures, creep and mechanical fatigue. The response of the material at high temperatures (20–700 °C) is shown in the form of engineering stress-strain diagrams while that at creep behavior (400–600 °C) is shown in the form of creep curves. Furthermore, based on uniaxial fully reversed mechanical fatigue tests (R=−1), a stress-life (S-N) fatigue diagram has been constructed and the fatigue (endurance) limit of the material is calculated The experimentally determined value of tensile strength at room temperature is 534 MPa. The calculated value of the fatigue limit, also at room temperature, using the modified staircase method and based on the mechanical fatigue tests data, is 202 MPa. With regard to creep resistance, steel 1.0122 can be considered creep-resistant only at a temperature of 400 °C and at an applied stress not exceeding 50% of the yield strength corresponding to this temperature.

Room temperature freezing and orientational control of surface-immobilized peptides in air

2015 ◽  
Vol 51 (55) ◽  
pp. 11015-11018 ◽  
Author(s):  
Yaoxin Li ◽  
Xiaoxian Zhang ◽  
John Myers ◽  
Nicholas L. Abbott ◽  
Zhan Chen
Keyword(s):  
High Temperatures ◽  
Room Temperature ◽  
Peptide Structure ◽  
Native Structure ◽  
Immobilized Peptide

The “native” structure and orientation of a surface immobilized peptide was successfully controlled in air with a sugar layer. The robust peptide structure could also be retained at high temperatures.

Perancangan Sistem Pengaturan Suhu Ruangan Otomatis Berbasis Mikrokontroler

2019 ◽  
Vol 8 (1) ◽  
pp. 95
Author(s):  
I Wayan Gede Partamayasa ◽  
I Ketut Gede Suhartana ◽  
I Wayan Supriana
Keyword(s):  
High Temperatures ◽  
Room Temperature ◽  
Network Communication ◽  
The Internet ◽  
Humidity Sensors ◽  
Temperature And Humidity ◽  
Communication Devices ◽  
Internet Network

A server room is a room that is used to store servers, network communication devices such as routers and switches, and other operational related devices. Server rooms that have high temperatures and humidity will affect the performance of all devices, so the temperature and humidity of the server room must be maintained so that the device is not easily damaged. So from that, the company needs to implement a standard to protect the performance of the devices stored in it. To overcome this problem a device was developed that can automatically control and monitor temperature and humidity. The system will be built using temperature and humidity sensors that are used to monitor the temperature of the room, the condition of the room temperature and humidity of the room will be displayed through a website that can be accessed through the internet network.

Change in the Properties of a Lead-acid Battery Depending on the Cycling Speed and the Ambient Temperature

2021 ◽  
Vol 105 (1) ◽  
pp. 119-134
Author(s):  
Jana Zimáková ◽  
Petr Baca ◽  
Martin Langer ◽  
Tomáš Binar
Keyword(s):  
Ambient Temperature ◽  
High Temperatures ◽  
Room Temperature ◽  
Lead Acid Battery ◽  
Ambient Temperatures ◽  
Lead Acid Batteries ◽  
Temperature Dependences ◽  
Cycling Speed ◽  
Lead Acid

This work deals with lead-acid batteries, their properties and individual types that are available on the market. The temperature dependences of the battery parameters at different ambient temperatures and at different discharging and charging modes are measured. 6 batteries are tested at different charging currents, which provides information about their behavior both during discharge and at the time of charging. During the experiments, testing is not only performed at room temperature, but the batteries are also exposed to high temperatures up to 75 °C.

Investigations on Phosphate Cements Hardening at Room Temperature

1989 ◽  
Vol 179 ◽  
Author(s):  
Alfred Zurz ◽  
I. Odler ◽  
B. Dettki
Keyword(s):  
Ultimate Strength ◽  
Room Temperature ◽  
Main Reaction ◽  
Main Reaction Product

AbstractPastes prepared from diammonium orthophosphate and calcined magnesia, MgO, exhibit a fast setting and hardening associated with NH3 liberation. Struvite, MgNH4PO4.6H2O, was found to be the main reaction product. Pastes made with NaH2PO4 or Na-polyphosphate exhibit a similar hardening reaction. The hardening reaction may be retarded and the ultimate strength moderately increased by adding appropriate retarders, such as Na2B4O7 10H2O to the system. The quality of the used MgO and its fineness has a significant effect on the rate of the hardening reaction.

THE SUSCEPTIBILITY OF SPERMATOZOA TO TEMPERATURE SHOCK

1959 ◽  
Vol 19 (3) ◽  
pp. 211-220 ◽  
Author(s):  
R. G. WALES ◽  
I. G. WHITE
Keyword(s):  
High Temperatures ◽  
Seminal Plasma ◽  
Room Temperature ◽  
Cold Shock ◽  
Differential Staining ◽  
Temperature Shock

SUMMARY The susceptibility of bull, ram, rabbit, dog, human and fowl spermatozoa to cold shock and high temperatures has been assessed. Motility and differential staining were used as criteria. Ram and bull spermatozoa were increasingly affected by cold shock at temperatures below 15° C; other spermatozoa were, however, little affected. Epididymal ram spermatozoa, particularly those with an attached kinoplasmic droplet, were more resistant than ejaculated ones; the addition of seminal plasma had little effect. Second ejaculates from bulls were slightly more resistant than first ejaculates. Washing bull or fowl spermatozoa free of seminal plasma did not influence their susceptibility to cold shock. Five min at 50° C severely depressed the motility of all spermatozoa except those of the fowl which were, however, completely immobilized at 55° C. Most spermatozoa took up stain more readily when mixed with it at high temperatures than when brought back to room temperature and then mixed; this is due to an increase in the toxicity of the stain at high temperatures.

C60 UNDER PRESSURE

1992 ◽  
Vol 06 (19) ◽  
pp. 1153-1158 ◽  
Author(s):  
MANUEL NÚÑEZ-REGUEIRO
Keyword(s):  
Phase Diagram ◽  
High Pressure ◽  
High Temperatures ◽  
Room Temperature ◽  
Fullerene Cage ◽  
Temperature Phase ◽  
Bonded Phase ◽  
Temperature Phase Diagram

The high pressure experiments done on fullerenes are reviewed. C 60 has found to be stable up to about 20 GPa at room temperature and hydrostatic conditions. Application of stronger, or non-hydrostatic, pressures at room temperature can induce the formation of a partially sp3 bonded phase, that apparently conserves the fullerene cage. Extreme non-hydrostatic compressions above about 15 GPa can, though, break down the cage and produce amorphous or cubic diamond. Destruction of the cage at high temperatures has also been observed, but the resulting product is amorphous sp2 material. A preliminary pressure-temperature phase diagram for C 60 is proposed.

1700V, 5.5mOhm-cm2 4H-SiC DMOSFET with Stable 225°C Operation

2014 ◽  
Vol 778-780 ◽  
pp. 903-906 ◽  
Author(s):  
Kevin Matocha ◽  
Kiran Chatty ◽  
Sujit Banerjee ◽  
Larry B. Rowland
Keyword(s):  
High Temperature ◽  
Temperature Stress ◽  
High Temperatures ◽  
Threshold Voltage ◽  
Room Temperature ◽  
Gate Bias ◽  
Threshold Voltage Shift ◽  
Device Reliability ◽  
Bias Temperature Stress ◽  
High Temperature Operation

We report a 1700V, 5.5mΩ-cm24H-SiC DMOSFET capable of 225°C operation. The specific on-resistance of the DMOSFET designed for 1200V applications is 8.8mΩ-cm2at 225°C, an increase of only 60% compared to the room temperature value. The low specific on-resistance at high temperatures enables a smaller die size for high temperature operation. Under a negative gate bias temperature stress (BTS) at VGS=-15 V at 225°C for 20 minutes, the devices show a threshold voltage shift of ΔVTH=-0.25 V demonstrating one of the key device reliability requirements for high temperature operation.

The photochemical and thermal decompositions of hydrogen sulphide

1953 ◽  
Vol 216 (1126) ◽  
pp. 344-361 ◽  
Keyword(s):  
Thermal Decomposition ◽  
Quantum Yield ◽  
Hydrogen Sulphide ◽  
Low Temperatures ◽  
Room Temperature ◽  
Large Fraction ◽  
Kcal Mole ◽  
Hydrogen Atoms ◽  
Photochemical Decomposition ◽  
Bimolecular Mechanism

The photochemical decomposition of hydrogen sulphide has been investigated at pressures between 8 and 550 mm of mercury and at temperatures between 27 and 650° C, using the narrow cadmium line ( λ 2288) and the broad mercury band (about λ 2550). At room temperature the quantum yield increases with pressure from 1.09 at 30 mm to 1.26 at 200 mm. Above 200 mm pressure there was no further increase in the quantum yield. Temperature had little effect on the quantum yield at λ 2550, but there was a marked increase in the rate of hydrogen production between 500 and 650° C with 2288 Å radiation. This may have been caused by the decomposition of excited hydrosulphide radicals. The results are consistent with a mechanism involving hydrogen atoms and hydrosulphide radicals. The mercury-photosensitized reaction is less efficient than the photochemical decomposition, the quantum yield being only about 0.45. The efficiency increased with temperature and approached unity at high temperatures and pressures. This agrees with the suggestion that a large fraction of the quenching collisions lead to the formation of Hg ( 3 P 0 ) atoms. The thermal decomposition is heterogeneous at low temperatures and becomes homogeneous and of the second order at 650° C. The experimental evidence suggests the bimolecular mechanism 2H 2 S → 2H 2 + S 2 . The activation energies are 25 kcal/mole (heterogeneous) and 50 kcal/mole (homogeneous).

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