How to get to the children's kingdom in Naha, Okinawa
Publish: 2021-05-11 10:28:11
1. bitcoin is a kind of virtual digital currency. Gold coins will be created when trading. Of course, the number is very rare
the bitcoin transaction process takes about two hours, in which the security will be confirmed. The longer the transaction time, the higher the security factor
there is no discrimination.
the bitcoin transaction process takes about two hours, in which the security will be confirmed. The longer the transaction time, the higher the security factor
there is no discrimination.
2. Method 1: find a place with good light (or use a flashlight), and look at the iron sheet under the password finger wheel. If you look carefully, you will find a small gap. Turn the three gaps to the left, and then subtract three (5) from each number to the left, which is the password. But the key of the pull bar box of different brands is different. Method 2: turn the wheel of the password box to the place with strong light, If you look inside the gap of each runner and slowly rotate the runner, you can see that there are two depressions on the runner. Adding 5 to the big depression is the password of the runner. For example, if the depressions of the three runners are above 240, the password is 795 (2 + 5 = 7,4 + 5 = 9,0 + 5 = 5). First, set all the three password numbers to zero. Then do it as follows:
Press and hold the button with one hand, use a little force to open the button, and then use the other hand to adjust the first digit of the password, that is, the nearest digit to the button. Try one digit by one... Don't be afraid of trouble
when your number is adjusted correctly, the hand holding down the button will feel that the button has a certain displacement, and then start to adjust the next digit... Until all three digits are adjusted correctly, the button will open automatically
I don't know if you understand. Hope to help you.
Press and hold the button with one hand, use a little force to open the button, and then use the other hand to adjust the first digit of the password, that is, the nearest digit to the button. Try one digit by one... Don't be afraid of trouble
when your number is adjusted correctly, the hand holding down the button will feel that the button has a certain displacement, and then start to adjust the next digit... Until all three digits are adjusted correctly, the button will open automatically
I don't know if you understand. Hope to help you.
3. Zip file password decoding:
download / utility / encrpt / 4804 / utility / encrpt / 12456 / utility / encrpt / 9295 / utility / encrpt / 4798. HTML
zip / rar / ACE / ARJ / PDF
decryption toolkit
the toolkit contains four Chinese software: 1. Advanced
archive
password
recovery
2.0
Chinese version; It can solve the password of
zip / PKZIP / winzip, ARJ / winarj, rar / WinRAR
(2. X)
and
ACE / winace
(2. X)
and other compressed files
2. Advanced
zip
password
recovery
3.52
Chinese version; It can unlock the password of
zip
compressed file; 3. Advanced
rar
password
recovery
1.11
Chinese version; It can unlock the password of
rar
compressed file
4. Advanced
PDF
password
recovery
Pro
1.01
Chinese version. You can unlock the password of
PDF
files
address:
/ soft / 343. HTML
rar
password
recovery
v1.1
rc16
rar / WinRAR compressed file password cracking tool, supporting brute force cracking, dictionary cracking and extremely fast & quot; Booost-Up" Crack method, can also interrupt the calculation and recovery, continue the previous calculation
address:
/ soft / 2308. HTML
Advanced
rar
password
recovery
v1.52
Chinese version
a program to recover the password of RAR / WinRAR files lost or forgotten. It supports customizable brute force cracking and dictionary cracking, and provides a multilingual interface
this new version includes: can work in AV record files; Recover the password of some special files; When the recovery is completed, it can be saved automatically and quickly. The interface of the software is very simple and easy to use. At the same time, it has powerful functions. Theoretically, it can solve any rar file password. Of course, the longer the password is, the longer the time will be:)
address:
/ soft / 4548. HTML
rar
password
recovery
v1.1
Chinese version
rar
password
recovery
is a password cracking tool that can help you quickly retrieve the decompression password of RAR / WinRAR compressed package that you have lost or forgotten. The program supports brute force cracking, dictionary based cracking and very unique & quot; Acceleration & quot
password cracking mode, and can resume the password cracking work which was stopped unexpectedly last time at any time! Similar to the breakpoint continuation function, very practical
address:
/ soft / 4299. HTML
Advanced
rar
password
recovery
v1.52
a fast password that can help you retrieve the rar file, and can unlock up to 128 passwords after registration. It provides an estimate of the time required to work out the password; Interruptible computation and recovery continue the previous computation
address:
/ soft / 2009. HTML
rar
key
v7.0.1180
rar
key can recover the password of rar file, use brute force cracking and dictionary attack to recover the password of RAR
2. X file, support multilingual password. The program can save the password automatically every time
address:
/ soft / 4525. HTML
rar
password
recovery
key
V6.3
rar
key
is one of a series of password recovery softwares made by
passware
it is a powerful password cracking tool for rar compressed package. The program can recover the password of RAR containing self decompressed files by using brute force, xieve and Dictionary attack is used to recover the password of RAR
2. X
files. It supports multi language password and can automatically save the cracking progress. It should be noted that it does not support password recovery of rar3. X
or above
s / N: r9e2-sx42-q7jc-dg5ej
address:
/ soft / 3600. HTML
passware
rar
password
recovery
key
V6.5
rar
key can recover the password of rar file. Brute force cracking and dictionary attack can be used to recover the password of RAR
2. X file, supporting multilingual password. The program can save the password automatically every time
address:
/ soft / 3891.html
download / utility / encrpt / 4804 / utility / encrpt / 12456 / utility / encrpt / 9295 / utility / encrpt / 4798. HTML
zip / rar / ACE / ARJ / PDF
decryption toolkit
the toolkit contains four Chinese software: 1. Advanced
archive
password
recovery
2.0
Chinese version; It can solve the password of
zip / PKZIP / winzip, ARJ / winarj, rar / WinRAR
(2. X)
and
ACE / winace
(2. X)
and other compressed files
2. Advanced
zip
password
recovery
3.52
Chinese version; It can unlock the password of
zip
compressed file; 3. Advanced
rar
password
recovery
1.11
Chinese version; It can unlock the password of
rar
compressed file
4. Advanced
password
recovery
Pro
1.01
Chinese version. You can unlock the password of
files
address:
/ soft / 343. HTML
rar
password
recovery
v1.1
rc16
rar / WinRAR compressed file password cracking tool, supporting brute force cracking, dictionary cracking and extremely fast & quot; Booost-Up" Crack method, can also interrupt the calculation and recovery, continue the previous calculation
address:
/ soft / 2308. HTML
Advanced
rar
password
recovery
v1.52
Chinese version
a program to recover the password of RAR / WinRAR files lost or forgotten. It supports customizable brute force cracking and dictionary cracking, and provides a multilingual interface
this new version includes: can work in AV record files; Recover the password of some special files; When the recovery is completed, it can be saved automatically and quickly. The interface of the software is very simple and easy to use. At the same time, it has powerful functions. Theoretically, it can solve any rar file password. Of course, the longer the password is, the longer the time will be:)
address:
/ soft / 4548. HTML
rar
password
recovery
v1.1
Chinese version
rar
password
recovery
is a password cracking tool that can help you quickly retrieve the decompression password of RAR / WinRAR compressed package that you have lost or forgotten. The program supports brute force cracking, dictionary based cracking and very unique & quot; Acceleration & quot
password cracking mode, and can resume the password cracking work which was stopped unexpectedly last time at any time! Similar to the breakpoint continuation function, very practical
address:
/ soft / 4299. HTML
Advanced
rar
password
recovery
v1.52
a fast password that can help you retrieve the rar file, and can unlock up to 128 passwords after registration. It provides an estimate of the time required to work out the password; Interruptible computation and recovery continue the previous computation
address:
/ soft / 2009. HTML
rar
key
v7.0.1180
rar
key can recover the password of rar file, use brute force cracking and dictionary attack to recover the password of RAR
2. X file, support multilingual password. The program can save the password automatically every time
address:
/ soft / 4525. HTML
rar
password
recovery
key
V6.3
rar
key
is one of a series of password recovery softwares made by
passware
it is a powerful password cracking tool for rar compressed package. The program can recover the password of RAR containing self decompressed files by using brute force, xieve and Dictionary attack is used to recover the password of RAR
2. X
files. It supports multi language password and can automatically save the cracking progress. It should be noted that it does not support password recovery of rar3. X
or above
s / N: r9e2-sx42-q7jc-dg5ej
address:
/ soft / 3600. HTML
passware
rar
password
recovery
key
V6.5
rar
key can recover the password of rar file. Brute force cracking and dictionary attack can be used to recover the password of RAR
2. X file, supporting multilingual password. The program can save the password automatically every time
address:
/ soft / 3891.html
4. Cl (CAS
latency): is the delay time of CAS, which is the response time of longitudinal address pulse. It is also one of the important marks to measure the memory supporting different specifications at a certain frequency
the memory is responsible for providing the CPU with the raw data needed for the operation. At present, the running speed of the CPU is much faster than the data transmission speed of the memory. Therefore, in many cases, the CPU needs to wait for the memory to provide data, which is often called "CPU waiting time". The slower the memory transfer speed, the longer the CPU waiting time, and the greater the impact on the overall performance of the system. Therefore, fast memory is one of the keys to improve CPU efficiency and overall performance
in actual work, no matter what type of memory, before the data is transmitted, the sender must spend a certain amount of time waiting for the response of the transmission request. Generally speaking, the sender and the receiver must communicate before transmission, which will cause a certain delay of transmission. To some extent, the setting of CL reflects the waiting time from the CPU receiving the instruction of reading memory data to the beginning of reading data. It is not difficult to see that with the same frequency of memory, the low Cl setting has more speed advantage
the above is just to establish a basic CL concept for you, but in fact, the basic factors of memory latency are definitely more than these. Memory latency has a special term called latency. To understand the delay vividly, we might as well regard the memory as an array storing data, or an excel table. To determine the position of each data, each data is marked by row and column sorting numbers. After determining the row and column serial numbers, the data will be unique. When the memory is working, to read or write some data, the memory control chip will first transmit the column address of the data, and the RAS signal (row
address
strobe, row address signal) will be activated. Before converting to row data, it needs to go through several execution cycles, and then the CAS signal (column
address
strobe, column address signal) will be activated. Several execution cycles between RAS signal and CAS signal are RAS to CAS delay time. It also needs several execution cycles after CAS signal is executed. This execution cycle is about 2 to 3 cycles in SDRAM using standard PC133; DDR
ram is 4 to 5 cycles. In DDR, the real CAS latency is 2 to 2.5 execution cycles. The time of RAS to CAS depends on the technology, about 5 to 7 cycles, which is also the basic factor of delay
CL setting lower memory has a higher advantage, which can be shown by the total latency. There is a formula to calculate the total delay time of memory. The total delay time = system clock cycle × CL mode number + access time (TAC). First of all, let's understand the concept of access time (TAC). TAC is the abbreviation of access
time
from
CLK, which refers to the maximum number of input clocks at the maximum CAS delay. It is in nanoseconds, which is completely different from the concept of memory clock cycle, although it is in nanoseconds. Access time (TAC) represents the time of reading and writing, while clock frequency represents the speed of memory
take an example to calculate the total delay time. For example, the access time of a ddr333 memory is 6ns, and the memory clock cycle is 6ns (DDR memory clock cycle = 1x2 / memory frequency, DDR400 memory frequency is 400, then the clock cycle is 6ns). If we set CL to 2.5 in the BIOS of the motherboard, the total delay time is 6ns
x2.5 + 6ns = 21ns. If CL is set to 2, the total delay time is 6ns
x2 + 6ns = 18
ns, which reces the time by 3ns
in terms of the total delay time, the CL value plays a key role. Therefore, users who have high system requirements and like overclocking usually prefer to buy memory with low Cl value. At present, in addition to improving DDR performance by increasing memory clock frequency, memory granule manufacturers have considered further recing CAS delay time to improve memory performance
however, it does not mean that the lower the CL value, the better the performance, because other factors will affect this data. For example, the cache of the new generation processor is more efficient, which means that the processor reads less data directly from memory. Moreover, column data will be accessed more often, so RAS to CAS is more likely to occur, and the reading time will increase. Finally, sometimes a large amount of data will be read at the same time. In this case, the adjacent memory data will be read out at one time, and the CAS delay time will only occur once
when you choose to buy memory, you'd better choose the memory with the same cl setting, because when memory with different speeds is mixed in the system, the system will run at a slower speed, that is, when the memory of cl2.5 and Cl2 is inserted in the host at the same time, the system will automatically make both memory work in cl2.5 state, causing a waste of resources.
latency): is the delay time of CAS, which is the response time of longitudinal address pulse. It is also one of the important marks to measure the memory supporting different specifications at a certain frequency
the memory is responsible for providing the CPU with the raw data needed for the operation. At present, the running speed of the CPU is much faster than the data transmission speed of the memory. Therefore, in many cases, the CPU needs to wait for the memory to provide data, which is often called "CPU waiting time". The slower the memory transfer speed, the longer the CPU waiting time, and the greater the impact on the overall performance of the system. Therefore, fast memory is one of the keys to improve CPU efficiency and overall performance
in actual work, no matter what type of memory, before the data is transmitted, the sender must spend a certain amount of time waiting for the response of the transmission request. Generally speaking, the sender and the receiver must communicate before transmission, which will cause a certain delay of transmission. To some extent, the setting of CL reflects the waiting time from the CPU receiving the instruction of reading memory data to the beginning of reading data. It is not difficult to see that with the same frequency of memory, the low Cl setting has more speed advantage
the above is just to establish a basic CL concept for you, but in fact, the basic factors of memory latency are definitely more than these. Memory latency has a special term called latency. To understand the delay vividly, we might as well regard the memory as an array storing data, or an excel table. To determine the position of each data, each data is marked by row and column sorting numbers. After determining the row and column serial numbers, the data will be unique. When the memory is working, to read or write some data, the memory control chip will first transmit the column address of the data, and the RAS signal (row
address
strobe, row address signal) will be activated. Before converting to row data, it needs to go through several execution cycles, and then the CAS signal (column
address
strobe, column address signal) will be activated. Several execution cycles between RAS signal and CAS signal are RAS to CAS delay time. It also needs several execution cycles after CAS signal is executed. This execution cycle is about 2 to 3 cycles in SDRAM using standard PC133; DDR
ram is 4 to 5 cycles. In DDR, the real CAS latency is 2 to 2.5 execution cycles. The time of RAS to CAS depends on the technology, about 5 to 7 cycles, which is also the basic factor of delay
CL setting lower memory has a higher advantage, which can be shown by the total latency. There is a formula to calculate the total delay time of memory. The total delay time = system clock cycle × CL mode number + access time (TAC). First of all, let's understand the concept of access time (TAC). TAC is the abbreviation of access
time
from
CLK, which refers to the maximum number of input clocks at the maximum CAS delay. It is in nanoseconds, which is completely different from the concept of memory clock cycle, although it is in nanoseconds. Access time (TAC) represents the time of reading and writing, while clock frequency represents the speed of memory
take an example to calculate the total delay time. For example, the access time of a ddr333 memory is 6ns, and the memory clock cycle is 6ns (DDR memory clock cycle = 1x2 / memory frequency, DDR400 memory frequency is 400, then the clock cycle is 6ns). If we set CL to 2.5 in the BIOS of the motherboard, the total delay time is 6ns
x2.5 + 6ns = 21ns. If CL is set to 2, the total delay time is 6ns
x2 + 6ns = 18
ns, which reces the time by 3ns
in terms of the total delay time, the CL value plays a key role. Therefore, users who have high system requirements and like overclocking usually prefer to buy memory with low Cl value. At present, in addition to improving DDR performance by increasing memory clock frequency, memory granule manufacturers have considered further recing CAS delay time to improve memory performance
however, it does not mean that the lower the CL value, the better the performance, because other factors will affect this data. For example, the cache of the new generation processor is more efficient, which means that the processor reads less data directly from memory. Moreover, column data will be accessed more often, so RAS to CAS is more likely to occur, and the reading time will increase. Finally, sometimes a large amount of data will be read at the same time. In this case, the adjacent memory data will be read out at one time, and the CAS delay time will only occur once
when you choose to buy memory, you'd better choose the memory with the same cl setting, because when memory with different speeds is mixed in the system, the system will run at a slower speed, that is, when the memory of cl2.5 and Cl2 is inserted in the host at the same time, the system will automatically make both memory work in cl2.5 state, causing a waste of resources.
5. PC material is a kind of chemical synthesis, which is widely used in daily life, especially in instry. This kind of synthesis is safe and non-toxic, and has many functions. Its existence promotes the development of instry, and has a high position in the development of instry. Polycarbonate
polycarbonate (PC) is a kind of polymer with carbonate group in the molecular chain. According to the structure of ester group, PC can be divided into aliphatic group, aromatic group, aliphatic aromatic group and so on. Because of the low mechanical properties of aliphatic and aliphatic aromatic polycarbonates, their applications in engineering plastics are limited
only aromatic polycarbonate has been instrialized. Due to the special structure of polycarbonate, it has become the fastest growing general engineering plastics among the five engineering plastics
Chinese name
polycarbonate
English name
polycarbonate
nickname
PC plastic
chemical formula
2,2 & # 39- Bis (4-hydroxyphenyl) propane polycarbonate
CAS accession number
25037-45-0
melting point
220-230 ℃
water soluble
insoluble
density
1200kg / m3
safety description
inedible
polycarbonate fiber polycarbonate structural polycarbonate what material ASA resin PC plastic PC what material polycarbonate price PC material polycarbonate price trend Figure PC material
composition
polycarbonate is a kind of strong thermoplastic resin, its name comes from its internal CO3 group. It can be synthesized from bisphenol A and carbon oxychloride (CoCl2). The most commonly used method is melt transesterification (Synthesis of bisphenol A and diphenyl carbonate by transesterification and polycondensation)
reaction principle of bisphenol A and diphenyl carbonate:
properties
chemistry
polycarbonate (PC) is a kind of polyester of carbonic acid. Carbonic acid itself is not stable, but its derivatives (such as phosgene, urea, carbonate, carbonate) have certain stability
polycarbonate can be divided into aliphatic group and aromatic group according to different alcohol structures
aliphatic polycarbonate. For example, poly (ethylene carbonate), poly (trimethylene carbonate) and their copolymers can not be used as structural materials because of their low melting point and glass transition temperature and poor strength; However, e to its biocompatibility and biodegradability, it can be used in drug delivery carriers, surgical sutures, bone support materials, etc
polycarbonate is resistant to weak acid, weak alkali and neutral oil
polycarbonate is not resistant to ultraviolet light and strong alkali
PC is a kind of linear carbonated polyester, in which carbonic acid groups are alternately arranged with other groups, which can be aromatic, aliphatic or both. BPA PC is the most important instrial proct
PC is almost colorless glassy amorphous polymer with good optical properties. PC high molecular weight resin has high toughness, the notched impact strength of cantilever beam is 600 ~ 900j / m, and the thermal deformation temperature of unfilled grade is about 130 ℃ ° C. Glass fiber reinforcement can increase this value by 10% ° C The bending molus of PC can reach more than 2400mpa, and the resin can be processed into large rigid procts. Below 100 ° The creep rate under load is very low at C. PC has poor hydrolysis resistance and can not be used for procts repeatedly subjected to high pressure steam
the main performance defects of PC are low hydrolysis resistance, sensitivity to notch, poor resistance to organic chemicals, poor scratch resistance, and yellowing after long-term exposure to ultraviolet light. Like other resins, PC is easily eroded by some organic solvents
PC material has flame retardancy. Antioxidant activity
physical
density: 1.18-1.22 g / cm ^ 3 linear expansion: 3.8 × 10^-5 cm/ ° C hot deformation temperature: 135 ° C low temperature - 45 ° C
polycarbonate is colorless, transparent, heat-resistant, impact resistant, flame retardant, Bi grade, and has good mechanical properties at ordinary service temperature. Compared with polymethyl methacrylate, polycarbonate has better impact resistance, high refractive index, good processability and UL94 V-2 flame retardancy without additives. However, the price of PMMA is lower than that of polycarbonate, and large devices can be proced by bulk polymerization
the wear resistance of the material is relative. Compared with PC material, ABS material has better wear resistance. However, compared with most of the plastic materials, the wear resistance of polycarbonate is relatively poor, which is in the middle and lower level. Therefore, some polycarbonate devices used for easy wear need special surface treatment
classification
antistatic PC, conctive PC, fiber reinforced fireproof PC, UV resistant and weather resistant PC, food grade PC, chemical resistant PC
main advantages
1
2. High transparency and free staining< 3. Low shrinkage and good dimensional stability
4
5
6. Excellent electrical characteristics< Mechanical properties: high strength, fatigue resistance, dimensional stability and small creep (little change at high temperature)< 2. Heat aging resistance: the enhanced UL temperature index is 120 ~ 140 ℃ (outdoor long-term aging is also good)< 3. Solvent resistance: no stress cracking
4. Water stability: it is easy to decompose when meeting water at high temperature (caution should be taken when using in high temperature and high humidity environment)< Electrical properties:
5. Electrical properties:
6. Insulation properties: excellent (moisture, high temperature can also maintain stable electrical properties, is an ideal material for manufacturing electronic and electrical parts)
7. Dielectric coefficient: 3.0-3.2
8. Arc resistance: 120s
9. Molding processability: injection molding or extrusion molding with ordinary equipment
adhesion of PC plastic
according to different needs, the following adhesives can be selected:
1. G-933: one component room temperature curable soft elastic shockproof adhesive, high and low temperature resistance, different viscosity, bonding speed, several seconds to several hours, curing completed
2. Kd-833 instant adhesive can quickly bond PC plastics for several seconds or tens of seconds, but the adhesive layer is hard and brittle, and can't withstand hot water immersion above 60 ℃< Qn-505, two-component adhesive, soft adhesive layer, suitable for large area bonding or composite of PC plastics. But the high temperature resistance is poor< Qn-906: two component adhesive, high temperature resistant
5. G-988: one component room temperature vulcanizate is an elastomer after curing. It has excellent waterproof and shockproof adhesive, high and low temperature resistance. If the thickness is 1-2mm, it will be initially cured in about 10 minutes and basically cured in 5-6 hours, with certain strength. It will take at least 24 hours to fully cure. Single component, no need to mix, after extrusion, daub and stand, no need to heat
6. Kd-5606: UV curing adhesive, bonding transparent PS sheet and plate, can achieve no trace effect, need to use UV lamp irradiation curing. The effect is beautiful after gluing. But the high temperature resistance is poor<
Application
development instry
the three major application fields of PC engineering plastics are glass assembly instry, automobile instry and electronic and electrical instry, followed by instrial mechanical parts, optical disk, packaging, computer and other office equipment, medical and health care, film, leisure and protective equipment, etc. PC can be used as window glass. PC laminate is widely used in protective windows of banks, embassies, detention centers and public places, as well as in aircraft canopy, lighting equipment, instrial safety baffle and bulletproof glass
the PC board can be used as various labels, such as gasoline pump dial, automobile instrument panel, warehouse and outdoor commercial label, point sliding indicator. The PC resin is used for automobile lighting system, instrument panel system and interior decoration system, as front lampshade, front and rear baffle with stiffener, reflector frame, door frame cover, operating rod sheath, choke plate, PC is used as junction box, socket Plug and sleeve, gasket, TV conversion device, connector of communication cable under telephone line bracket, switch box, telephone switchboard, distribution board components, relay shell. PC can be used as low load parts, such as motor of household appliances, vacuum cleaner, handle of shampoo, coffee machine, toaster, power tool, gear, worm gear, shaft sleeve, guide gauge, shelf in refrigerator. PC is an ideal material for optical disk storage
PC bottles (containers) are transparent, light in weight, good in impact resistance, and resistant to certain high temperature and corrosive solution washing, which can be used as recyclable bottles (containers). PC and PC alloy can be used as computer frame, shell, auxiliary machine and printer parts. The modified PC is resistant to high-energy radiation sterilization, steaming and baking disinfection, and can be used for blood sampling instruments, blood oxygenator, surgical instruments, renal dialyzer, etc. the PC can be used as helmet and helmet, protective mask, sunglasses and sports eye protection. PC film is widely used in printing charts, pharmaceutical packaging and membrane commutators
the application and development of polycarbonate is developing in the direction of high composite, high function, specialization and serialization. It has launched a variety of procts, such as CD-ROM, automobile, office equipment, box, packaging, medicine, lighting, film and so on.
polycarbonate (PC) is a kind of polymer with carbonate group in the molecular chain. According to the structure of ester group, PC can be divided into aliphatic group, aromatic group, aliphatic aromatic group and so on. Because of the low mechanical properties of aliphatic and aliphatic aromatic polycarbonates, their applications in engineering plastics are limited
only aromatic polycarbonate has been instrialized. Due to the special structure of polycarbonate, it has become the fastest growing general engineering plastics among the five engineering plastics
Chinese name
polycarbonate
English name
polycarbonate
nickname
PC plastic
chemical formula
2,2 & # 39- Bis (4-hydroxyphenyl) propane polycarbonate
CAS accession number
25037-45-0
melting point
220-230 ℃
water soluble
insoluble
density
1200kg / m3
safety description
inedible
polycarbonate fiber polycarbonate structural polycarbonate what material ASA resin PC plastic PC what material polycarbonate price PC material polycarbonate price trend Figure PC material
composition
polycarbonate is a kind of strong thermoplastic resin, its name comes from its internal CO3 group. It can be synthesized from bisphenol A and carbon oxychloride (CoCl2). The most commonly used method is melt transesterification (Synthesis of bisphenol A and diphenyl carbonate by transesterification and polycondensation)
reaction principle of bisphenol A and diphenyl carbonate:
properties
chemistry
polycarbonate (PC) is a kind of polyester of carbonic acid. Carbonic acid itself is not stable, but its derivatives (such as phosgene, urea, carbonate, carbonate) have certain stability
polycarbonate can be divided into aliphatic group and aromatic group according to different alcohol structures
aliphatic polycarbonate. For example, poly (ethylene carbonate), poly (trimethylene carbonate) and their copolymers can not be used as structural materials because of their low melting point and glass transition temperature and poor strength; However, e to its biocompatibility and biodegradability, it can be used in drug delivery carriers, surgical sutures, bone support materials, etc
polycarbonate is resistant to weak acid, weak alkali and neutral oil
polycarbonate is not resistant to ultraviolet light and strong alkali
PC is a kind of linear carbonated polyester, in which carbonic acid groups are alternately arranged with other groups, which can be aromatic, aliphatic or both. BPA PC is the most important instrial proct
PC is almost colorless glassy amorphous polymer with good optical properties. PC high molecular weight resin has high toughness, the notched impact strength of cantilever beam is 600 ~ 900j / m, and the thermal deformation temperature of unfilled grade is about 130 ℃ ° C. Glass fiber reinforcement can increase this value by 10% ° C The bending molus of PC can reach more than 2400mpa, and the resin can be processed into large rigid procts. Below 100 ° The creep rate under load is very low at C. PC has poor hydrolysis resistance and can not be used for procts repeatedly subjected to high pressure steam
the main performance defects of PC are low hydrolysis resistance, sensitivity to notch, poor resistance to organic chemicals, poor scratch resistance, and yellowing after long-term exposure to ultraviolet light. Like other resins, PC is easily eroded by some organic solvents
PC material has flame retardancy. Antioxidant activity
physical
density: 1.18-1.22 g / cm ^ 3 linear expansion: 3.8 × 10^-5 cm/ ° C hot deformation temperature: 135 ° C low temperature - 45 ° C
polycarbonate is colorless, transparent, heat-resistant, impact resistant, flame retardant, Bi grade, and has good mechanical properties at ordinary service temperature. Compared with polymethyl methacrylate, polycarbonate has better impact resistance, high refractive index, good processability and UL94 V-2 flame retardancy without additives. However, the price of PMMA is lower than that of polycarbonate, and large devices can be proced by bulk polymerization
the wear resistance of the material is relative. Compared with PC material, ABS material has better wear resistance. However, compared with most of the plastic materials, the wear resistance of polycarbonate is relatively poor, which is in the middle and lower level. Therefore, some polycarbonate devices used for easy wear need special surface treatment
classification
antistatic PC, conctive PC, fiber reinforced fireproof PC, UV resistant and weather resistant PC, food grade PC, chemical resistant PC
main advantages
1
2. High transparency and free staining< 3. Low shrinkage and good dimensional stability
4
5
6. Excellent electrical characteristics< Mechanical properties: high strength, fatigue resistance, dimensional stability and small creep (little change at high temperature)< 2. Heat aging resistance: the enhanced UL temperature index is 120 ~ 140 ℃ (outdoor long-term aging is also good)< 3. Solvent resistance: no stress cracking
4. Water stability: it is easy to decompose when meeting water at high temperature (caution should be taken when using in high temperature and high humidity environment)< Electrical properties:
5. Electrical properties:
6. Insulation properties: excellent (moisture, high temperature can also maintain stable electrical properties, is an ideal material for manufacturing electronic and electrical parts)
7. Dielectric coefficient: 3.0-3.2
8. Arc resistance: 120s
9. Molding processability: injection molding or extrusion molding with ordinary equipment
adhesion of PC plastic
according to different needs, the following adhesives can be selected:
1. G-933: one component room temperature curable soft elastic shockproof adhesive, high and low temperature resistance, different viscosity, bonding speed, several seconds to several hours, curing completed
2. Kd-833 instant adhesive can quickly bond PC plastics for several seconds or tens of seconds, but the adhesive layer is hard and brittle, and can't withstand hot water immersion above 60 ℃< Qn-505, two-component adhesive, soft adhesive layer, suitable for large area bonding or composite of PC plastics. But the high temperature resistance is poor< Qn-906: two component adhesive, high temperature resistant
5. G-988: one component room temperature vulcanizate is an elastomer after curing. It has excellent waterproof and shockproof adhesive, high and low temperature resistance. If the thickness is 1-2mm, it will be initially cured in about 10 minutes and basically cured in 5-6 hours, with certain strength. It will take at least 24 hours to fully cure. Single component, no need to mix, after extrusion, daub and stand, no need to heat
6. Kd-5606: UV curing adhesive, bonding transparent PS sheet and plate, can achieve no trace effect, need to use UV lamp irradiation curing. The effect is beautiful after gluing. But the high temperature resistance is poor<
Application
development instry
the three major application fields of PC engineering plastics are glass assembly instry, automobile instry and electronic and electrical instry, followed by instrial mechanical parts, optical disk, packaging, computer and other office equipment, medical and health care, film, leisure and protective equipment, etc. PC can be used as window glass. PC laminate is widely used in protective windows of banks, embassies, detention centers and public places, as well as in aircraft canopy, lighting equipment, instrial safety baffle and bulletproof glass
the PC board can be used as various labels, such as gasoline pump dial, automobile instrument panel, warehouse and outdoor commercial label, point sliding indicator. The PC resin is used for automobile lighting system, instrument panel system and interior decoration system, as front lampshade, front and rear baffle with stiffener, reflector frame, door frame cover, operating rod sheath, choke plate, PC is used as junction box, socket Plug and sleeve, gasket, TV conversion device, connector of communication cable under telephone line bracket, switch box, telephone switchboard, distribution board components, relay shell. PC can be used as low load parts, such as motor of household appliances, vacuum cleaner, handle of shampoo, coffee machine, toaster, power tool, gear, worm gear, shaft sleeve, guide gauge, shelf in refrigerator. PC is an ideal material for optical disk storage
PC bottles (containers) are transparent, light in weight, good in impact resistance, and resistant to certain high temperature and corrosive solution washing, which can be used as recyclable bottles (containers). PC and PC alloy can be used as computer frame, shell, auxiliary machine and printer parts. The modified PC is resistant to high-energy radiation sterilization, steaming and baking disinfection, and can be used for blood sampling instruments, blood oxygenator, surgical instruments, renal dialyzer, etc. the PC can be used as helmet and helmet, protective mask, sunglasses and sports eye protection. PC film is widely used in printing charts, pharmaceutical packaging and membrane commutators
the application and development of polycarbonate is developing in the direction of high composite, high function, specialization and serialization. It has launched a variety of procts, such as CD-ROM, automobile, office equipment, box, packaging, medicine, lighting, film and so on.
6. Yes, pt950 is 95 percent gold
7.
bus line: Metro Line 2 → Metro Line 1, the whole journey is about 28.0 km
1. Walk about 910 meters from children's kingdom to Likou station
2. Take Metro Line 2, pass 9 stations, reach Guangji South Road Station
3, walk about 80 meters, transfer to Metro Line 1
4. Take Metro Line 1, pass 14 stations, reach Zhongnan Street Station
5, walk about 520 meters, Arrive at Yongwang mengle City
8. Children's kingdom
the Ocean Expo Park was built in 1976 and rebuilt from the club of the first World Ocean Expo. It is the largest state-owned subtropical company in Japan. Now it is a must visit place for tourists to Okinawa and a tourist hotspot in Northern Okinawa. There are more than 200 kinds of fish aquarium, wonderful and interesting dolphin theater, Emerald Beach, marine culture museum, local village, botanical garden, tropical Dream Center, tropical and subtropical urban green botanical garden and sunset square. Absolutely let you spend unforgettable happy time here
in the three areas of the Ocean Expo Park, about 1000 points of living utensils and fishing tools showing the relationship with the marine ethnic groups in Southeast Asian countries are displayed in the ocean culture museum, and no ethnic group in the Ryukyu Archipelago has been involved since ancient times; omorosaushi" Among the singing plants, there are 22 kinds of representative exhibitions in historical and cultural areas.
the Ocean Expo Park was built in 1976 and rebuilt from the club of the first World Ocean Expo. It is the largest state-owned subtropical company in Japan. Now it is a must visit place for tourists to Okinawa and a tourist hotspot in Northern Okinawa. There are more than 200 kinds of fish aquarium, wonderful and interesting dolphin theater, Emerald Beach, marine culture museum, local village, botanical garden, tropical Dream Center, tropical and subtropical urban green botanical garden and sunset square. Absolutely let you spend unforgettable happy time here
in the three areas of the Ocean Expo Park, about 1000 points of living utensils and fishing tools showing the relationship with the marine ethnic groups in Southeast Asian countries are displayed in the ocean culture museum, and no ethnic group in the Ryukyu Archipelago has been involved since ancient times; omorosaushi" Among the singing plants, there are 22 kinds of representative exhibitions in historical and cultural areas.
9.
I think virtual currency should be suppressed because virtual currency is just an asset bubble.
some people are particularly optimistic about the prospect of virtual currency. They think that virtual currency will eventually replace the traditional currency we are using. However, in the current situation, virtual currency is only under the banner of replacing traditional currency, but it is controlled by traditional currency, which is a very embarrassing reality
What's the matter
China CITIC Bank has issued a clear notice to the outside world, and will prohibit all accounts from being used for bitcoin transactions in the future. This is a very explosive news, although not all bitcoin transactions are concted through China CITIC Bank< but when a bank starts to ban bitcoin trading, many banks will follow suit . This means that bitcoin trading will become a restriction for many banks, which is not concive to the whole bitcoin market{ RRRRR}
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