TRENDING HASHTAG: #definition
Trending Posts
-
jyhinge
Products
https://www.jyhinge.com/products/
#door #hinge #definition
Industrial Door Hinges
Industrial door hinge are robust, durable components designed to support heavy-duty doors in commercial and industrial settings. Made from high-strength... moreProducts
https://www.jyhinge.com/products/
#door #hinge #definition
Industrial Door Hinges
Industrial door hinge are robust, durable components designed to support heavy-duty doors in commercial and industrial settings. Made from high-strength materials like stainless steel or brass, these hinges ensure smooth operation and longevity under rigorous use. They come in various types, including butt, pivot, and continuous hinges, each offering unique benefits. Key features often include corrosion resistance, load-bearing capacity, and security enhancements. Whether for warehouses, factories, or commercial buildings, industrial door hinges are essential for safe and efficient door functionality. less
May 8
-
bird sat
SP80 Satellite TV Antennas
https://www.birdsat-vsat.com/products/sp80-satellite-tv-antennas/
#vsat #definition
BIRDSAT's new 80 cm KU band satellite TVRO antenna is on board now. Powerful and compact, shortened response time, every improvement is... moreSP80 Satellite TV Antennas
https://www.birdsat-vsat.com/products/sp80-satellite-tv-antennas/
#vsat #definition
BIRDSAT's new 80 cm KU band satellite TVRO antenna is on board now. Powerful and compact, shortened response time, every improvement is aiming at increase the life happiness experience on sea.
Features of SP80 Satellite TV Antennas
Quick response
Uninterrupted connection
Signal receiving strengthened less
April 18, 2023
-
gosdwan gosdwan
RMA Support #rma #support #definition
Pack and ship the product: The customer will then need to pack the product securely and ship it back to GoSDWAN, along with the RMA number. https://www.gosdwan.com/rma-support/
April 18, 2023
-
dehaiyouli
Definition and Raw Materials of Flat Belt
https://www.dehaiyouli.com/definition-and-raw-materials-of-flat-belt.html
#flat #belt #definition
Flat Belt Definition
Flat belt is a kind of power transmission belt with a flat surface, usually with uniform... moreDefinition and Raw Materials of Flat Belt
https://www.dehaiyouli.com/definition-and-raw-materials-of-flat-belt.html
#flat #belt #definition
Flat Belt Definition
Flat belt is a kind of power transmission belt with a flat surface, usually with uniform texture on both sides, used in pulley drive system. In history, flat belts usually use pulleys to transmit power to other parts of the machine, thereby driving the machine's operation.
Nowadays, they are commonly used as part of power transmission devices. There is a kind of belt drive that uses a flat belt, which is the thing we talk about. It operates through a drive and a pulley. The drive speed of a flat rubber belt can even exceed 3000 feet per minute. Specifically, the power is generated under the operation of the drive, and is transmitted from one shaft to the other through the belt, that is, when the two shafts are separated by a certain distance, a flat belt is required to transmit the power. less
September 22, 2022
-
gihi chem
Bacillus coagulans produces lactic acid and is often misclassified as lactobacillus. In fact, some commercial products containing Bacillus coagulans are marketed as Lactobacillus sporogenes. Unlike lactic acid bacteria such as lactobacillus or... moreBacillus coagulans produces lactic acid and is often misclassified as lactobacillus. In fact, some commercial products containing Bacillus coagulans are marketed as Lactobacillus sporogenes. Unlike lactic acid bacteria such as lactobacillus or bifidobacteria, Bacillus coagulans forms spores. Spores are an important factor in telling Bacillus coagulans apart from other lactic acid bacteria.
#bacillus #coagulans #definition
https://www.gihichem.com/products/bacillus-coagulans/ less
August 14, 2022
Do you want to report this? Why didn't you like it?
-
hxtechnology
Power PCBA Board
#pcb #pcba #definition
As a professional PCBA supplier, HX Technology is committed to providing high-quality power PCBA board services. The... morePower PCBA Board
#pcb #pcba #definition
As a professional PCBA supplier, HX Technology is committed to providing high-quality power PCBA board services. The product services cover industrial controller, medical equipment, telecommunications equipment, environmental protection equipment, instrumentation, security systems, and other fields. HX Technology’s power PCBA boards are exported to Europe and North America. With experienced, senior, stringent, and principled work styles, we aim to provide our customers with the best power PCBA board and good service feeling.
Application of Electronics PCBA
Electronic PCBA is mainly used in computer motherboard mouse board, graphics cards, office equipment, printers, copiers, shakers, all kinds of chargers, calculators, digital cameras, radios, TV motherboards, limited TV amplifiers, cell phones, washing machines, electronic scales, telephones, LED lamps, etc.
https://www.hx-technology.com/power-pcba-board.html less
June 27, 2022
-
-
wsxchem
Acid Anhydride Curing Agent Guide
#curing #agent #definition
The curing reaction mechanism of anhydrides can be divided into two forms according to the presence or absence of... moreAcid Anhydride Curing Agent Guide
#curing #agent #definition
The curing reaction mechanism of anhydrides can be divided into two forms according to the presence or absence of accelerators.
1. In the absence of accelerants, the hydroxyl group in epoxy resin reacts with anhydride first, and the anhydride is turned on, then the addition polymerization is carried out. The order is as follows:
Hydroxyl reacts with anhydride to form ester bond and carboxylic acid.
Carboxylic acid is added to epoxy group to form hydroxyl group.
The hydroxyl groups formed continue to react with other anhydrides.
The reaction proceeds repeatedly to form bulk polymers. In addition, in this system, due to the acidic state, the reaction parallel to the above reaction is the reaction of other epoxy groups with hydroxyl groups, resulting in the formation of ether bonds. From the above mechanism, it can be seen that there are two kinds of structures in the cured product: ether bond and ester bond, and the reaction rate is controlled by the concentration of epoxy group and hydroxyl group.
2. In the presence of accelerants, the acid anhydride curing reaction is promoted by Lewis base. Accelerators (usually tertiary amines) initiate an attack on anhydride. The main reactions are as follows:
accelerator attacked anhydride to form carboxylate anion.
carboxylate anion reacts with epoxy group to form oxygen anion.
oxygen anion reacts with other anhydrides to form carboxylate anion again.
In this way, acid anhydride reacts with epoxy group, and additive polymerization is carried out step by step. In the presence of promoter Lewis base, all the bonds formed are ester bonds, and no ether bond was found as in the absence of promoter.
In the presence of accelerants, the curing rate of epoxy resin is also controlled by the concentration of hydroxyl groups in the acceptor system. Therefore, the addition of accelerators is very effective for liquid epoxy resin, and the curing reaction can be completed at the temperature of the 120～150℃. But for solid epoxy resin, we should pay attention to the problem of very short application period. In the absence of accelerants, theoretically, an epoxy group should be used for an anhydride, but in fact, only 80%-90% of the theoretical chemical quantity is enough. In the presence of accelerants, the amount of anhydride used is the chemical theoretical quantity.
https://www.wsxchem.com/resources/acid-anhydride-curing-agent-guide.html less
March 31, 2021
Loading ...
Updates
Do you want to report this? Why didn't you like it?
Loading ...
Loading ...
There are no more results to show.
Find in Members
Find in Projects
Find in Channels
