Copper North Reports Exploration Program
An exploration program was conducted by Aurora Geosciences Ltd. (a company which was engaged by Copper North to provide geological, geophysical and logistical field services in the Northwest Territories) in 2012, which targeted stratiform, sedimentary rock-hosted, copper-silver mineralization, and included; geological mapping, 21.3 line km of induced polarization ("IP") surveys, 41.25 line km of ground-based extremely low frequency electromagnetic ("ELF-EM") surveys, 324 stream sediment samples and 690 biogeochemical samples. An additional 18,979.1 acres across 15 new mineral claims were staked to increase Copper North's land position in the Redstone Copperbelt.
Highlights include:
Identification of drill-ready targets at the Coates Lake and Johnson Vein properties
Delineation of chargeable IP anomalies at the north end of the Coates Lake property that extend along strike northwards 3,000 m from the limit of known stratiform copper-silver mineralization
Delineation and 3D modelling of a complex zone of chargeable IP anomalies that extends at least 1,000 m along strike at the south end of the Coates Lake property
ELF-EM surveys have been a useful tool to provide new data on structures and stratigraphy in the near and deep (<2 km) subsurface. This data can be used to help target exploration efforts and to de-risk the positioning of future drill holes
Several regional targets have been generated with anomalous stream sediment geochemistry, including samples that have returned assays of up to 490 ppm Cu
Biogeochemistry has the potential to locate stratiform copper-silver mineralization that is concealed beneath glacial sediment cover
President and Chief Executive Officer, Dr. Sally Eyre, commented, "The 4,000 m of chargeable strike length successfully identified in 2012, in addition to the 6,000 m strike length of known copper-silver mineralization demonstrated by historical drilling, indicates the geological potential for a conceptual stratiform, sedimentary rock-hosted copper target that spans up to 10,000 m of strike length at Coates Lake. In addition to this, the deposit remains open to the north and at depth to the west and southwest."
Coates Lake deposit
The Coates Lake deposit is a stratiform, sedimentary rock-hosted, copper-silver deposit, that is located 116 kilometres north-east of the Cantung mine, Tungsten, Northwest Territories. At Coates Lake, mineralization comprises a high-grade, laterally continuous zone that has a demonstrated strike-length of over 6,000 m and extends down-dip for at least 2,400 m.
IP Surveys
21.3 line km of IP surveys were conducted at Coates Lake over two areas: a northern area and a southern area. Pole-dipole surveys were carried out at a spacing of 50 m or 100 m, observing 6 dipoles for a total of 12 lines. All IP data was modelled to produce 2D psuedosections and the southern area was modelled in 3D. Modelled chargeability anomalies from IP surveys were found to be coincident with known zones of stratiform, disseminated copper-silver mineralization. Chargeable anomalies present on four lines extend 3,000 m along strike from the northern limit of known stratiform copper-silver mineralization. A chargeable zone in the south of the property extends over 1,000 m strike length and is evident on 8 lines.
Drill-ready targets have been identified at Coates Lake (see accompanying Map) to further assess the potential for a large, copper-silver deposit; focussing on extending known high grade zones of stratiform copper-silver mineralization and exploring for thicker mineralized zones.
2013年2月20日星期三
Tungsten Copper Metals
The 10 Most Crisis-prone Metals
Over the last few years, the rare earth market has taught investors about the dangers (and rewards) of geographically concentrated metals.
One nation — China — produces 86 percent of the planet’s rare earths. This dominance caused a panic in the market when Chinese exports were disrupted by government policies aimed at keeping rare earths in the country for domestic use.
Fear of a massive supply disruption subsequently drove prices of the metals higher, also lifting share prices of producing and exploration companies to dizzying heights.
A similar story unfolded recently in the graphite market. The top three graphite-producing nations control some 88 percent of global output. Again, this monopoly has raised fears of a supply crunch.
Which metal is next?
New data released by the United States Geological Survey (USGS) last month provides some clues.
The USGS information shows the breakdown of global production for over 80 metals and other mineral commodities, revealing which markets are the most geographically concentrated — and thus the most primed for supply crises due to political, social or geological problems in the biggest producing nations.
The mineral monopolies
Resource Investing News conducted its own exclusive analysis of the USGS data, compiling the numbers to tease out two metrics:
What percentage of global production is controlled by the top producing nation in the market?
What percentage of production is controlled by the top three producing nations as a group?
The table below shows the metals that are most tied to the fate of one or a few countries as well as metals that may be at risk of future supply shocks similar to those experienced by the rare earths and graphite markets.
Over the last few years, the rare earth market has taught investors about the dangers (and rewards) of geographically concentrated metals.
One nation — China — produces 86 percent of the planet’s rare earths. This dominance caused a panic in the market when Chinese exports were disrupted by government policies aimed at keeping rare earths in the country for domestic use.
Fear of a massive supply disruption subsequently drove prices of the metals higher, also lifting share prices of producing and exploration companies to dizzying heights.
A similar story unfolded recently in the graphite market. The top three graphite-producing nations control some 88 percent of global output. Again, this monopoly has raised fears of a supply crunch.
Which metal is next?
New data released by the United States Geological Survey (USGS) last month provides some clues.
The USGS information shows the breakdown of global production for over 80 metals and other mineral commodities, revealing which markets are the most geographically concentrated — and thus the most primed for supply crises due to political, social or geological problems in the biggest producing nations.
The mineral monopolies
Resource Investing News conducted its own exclusive analysis of the USGS data, compiling the numbers to tease out two metrics:
What percentage of global production is controlled by the top producing nation in the market?
What percentage of production is controlled by the top three producing nations as a group?
The table below shows the metals that are most tied to the fate of one or a few countries as well as metals that may be at risk of future supply shocks similar to those experienced by the rare earths and graphite markets.
2013年2月7日星期四
Tungsten Infiltrated
Tungsten base infiltrated metals with either copper or silver as infiltrates have been widely used in industry for many years. The major uses include missile vector control vanes, nozzle and throat materials, missile plume deflector shields, electrical contacts, resistance welding contacts, and porous emitters.
Recently, the aerospace industry has opened up an entirely new field for both tungsten-silver and tungsten-copper composites. These, with approximately 90 weight % tungsten have proven highly advantageous because of their excellent mach inability. Complicated forms of nozzles and inserts can now be machined from a powder metallurgy product. Excellent thermal shock resistance, especially during firings, ablative cooling by silver vapor or copper vapor, and approximately 10% less weight than pure tungsten, with much easier handling, are additional benefits of infiltrated compounds.
Infiltrated tungsten powder is extensively used as matrix support material in diamond rock drilling bits. Its main function is to hold the diamond grit in place and the purpose of infiltrating the tungsten powder is to form a strong chemical bond between the diamond and the matrix.
It has been estimated that only 1/10 of the diamond grit is actually consumed in the intended cutting application. The remainder of the grit is wasted either by being left over when the tool’s useful life has expired or by being pulled-out or broken during use due to poor attachment and inadequate support.
The ideal support for the cutting particles is to have a matrix hard enough so that it will gradually of delaminating, plowing, cracking, cutting and fatigue fracture. The displacement of the abrasive particle on the surface of the matrix and the subsequent passes of other abrasive particle cause the detachment of small chips, usually by a fatigue-controlled mechanism. If the matrix is more brittle in nature, with a propensity for cracking during plowing, then fracture is the primary material removal mechanism. The ability of the infiltrate alloy to hold the tungsten particles together, measured by the amount of ductility of the composite, has been shown to have a major effect on the amount of plastic deformation of the composite prior to the formation of micro cracks due to wear. Most of the diamond drill manufacturers and the geological exploration companies agree that the performance of the bit is greatly affected by the type of infiltrate alloy, even when the percentage of the infiltrate alloy does not exceed 30% by weight.
In addition, the use of secondary abrasive particles has been found to be a very effective method to improve the wear resistance of the MMC. Harder particles such as TiB2, TiC and TiN added to Ti powder caused a significant the samples infiltrated with 60Cu–40Ag and 65–70wt% tungsten in the samples infiltrated with 56Cu–43Zn–1Sn. The green compact and the graphite mold were placed in a box furnace under a partially protected atmosphere generated by adding activated carbon on top of the infiltrate alloy. The type of infiltration can be described as infiltration by capillary forces aided by gravity. That is, the infiltrate alloy was placed on top of the green compact. The temperature of the box furnace was kept 100C over the fusion temperature of the infiltrate.
In some of the 60Cu–40Ag and 56Cu–43Zn–1Sn samples, single additions of 3% by volume of SiO2, SiC and WC were made to the tungsten powder before infiltration. The material infiltrated was disk-shaped, 38 mm diameter and 6 mm thick.
Recently, the aerospace industry has opened up an entirely new field for both tungsten-silver and tungsten-copper composites. These, with approximately 90 weight % tungsten have proven highly advantageous because of their excellent mach inability. Complicated forms of nozzles and inserts can now be machined from a powder metallurgy product. Excellent thermal shock resistance, especially during firings, ablative cooling by silver vapor or copper vapor, and approximately 10% less weight than pure tungsten, with much easier handling, are additional benefits of infiltrated compounds.
Infiltrated tungsten powder is extensively used as matrix support material in diamond rock drilling bits. Its main function is to hold the diamond grit in place and the purpose of infiltrating the tungsten powder is to form a strong chemical bond between the diamond and the matrix.
It has been estimated that only 1/10 of the diamond grit is actually consumed in the intended cutting application. The remainder of the grit is wasted either by being left over when the tool’s useful life has expired or by being pulled-out or broken during use due to poor attachment and inadequate support.
The ideal support for the cutting particles is to have a matrix hard enough so that it will gradually of delaminating, plowing, cracking, cutting and fatigue fracture. The displacement of the abrasive particle on the surface of the matrix and the subsequent passes of other abrasive particle cause the detachment of small chips, usually by a fatigue-controlled mechanism. If the matrix is more brittle in nature, with a propensity for cracking during plowing, then fracture is the primary material removal mechanism. The ability of the infiltrate alloy to hold the tungsten particles together, measured by the amount of ductility of the composite, has been shown to have a major effect on the amount of plastic deformation of the composite prior to the formation of micro cracks due to wear. Most of the diamond drill manufacturers and the geological exploration companies agree that the performance of the bit is greatly affected by the type of infiltrate alloy, even when the percentage of the infiltrate alloy does not exceed 30% by weight.
In addition, the use of secondary abrasive particles has been found to be a very effective method to improve the wear resistance of the MMC. Harder particles such as TiB2, TiC and TiN added to Ti powder caused a significant the samples infiltrated with 60Cu–40Ag and 65–70wt% tungsten in the samples infiltrated with 56Cu–43Zn–1Sn. The green compact and the graphite mold were placed in a box furnace under a partially protected atmosphere generated by adding activated carbon on top of the infiltrate alloy. The type of infiltration can be described as infiltration by capillary forces aided by gravity. That is, the infiltrate alloy was placed on top of the green compact. The temperature of the box furnace was kept 100C over the fusion temperature of the infiltrate.
In some of the 60Cu–40Ag and 56Cu–43Zn–1Sn samples, single additions of 3% by volume of SiO2, SiC and WC were made to the tungsten powder before infiltration. The material infiltrated was disk-shaped, 38 mm diameter and 6 mm thick.
Tungsten Copper Mounts
Copper Tungsten Mounts Keep Diode Lasers Cool
In addition to traditional heat sinking in packaging of microelectronic dies, more demanding applications are emerging for copper/tungsten (WCu) metal-matrix composites (MMCs) as mounts and submounts for semiconductor laser diodes. Currently, the majority of semiconductor laser diodes are mounted on a mount or submount made out of WCu. Improved thermal expansion match between the heat sink and the die, coupled with the current trend of increasing die size and power-dissipation requirements, has made WCu the material of choice for packaging laser diodes. This is particularly true for die larger than 1000 µm in any direction. Copper/tungsten provides the needed thermal dissipation and good thermal expansion match. Some laser diodes are mounted directly on oxygen free high purity copper, on a beryllia or aluminum nitride ceramic substrate, or even on a diamond substrate.
The majority of power semiconductor laser diodes manufactured for wavelengths in the 800 to 1550 nm range have benefited from the improved performance of the new WCu heat sink bases. Applications include medical, scientific, and fiberoptic-based communication networks, among others.
Copper Tungsten Mounts Changing Conventions
Conventional copper tungsten heat sink bases provide thermal conductivity between 170 and 220 W/mK and a reduced coefficient of thermal expansion that matches the semiconductor dies for diode manufacturing (5.6-9.0 ppm/°C). Laser dies are typically built on gallium arsenide (GaAs) substrates using processes such as molecular-beam epitaxy or metal-organic chemical-vapor deposition. The final chemical composition may include indium gallium arsenide (InGaAs), indium aluminum gallium arsenide (InAlGaAs), aluminum gallium arsenide (AlGaAs), indium gallium arsenide phosphide (InGaAsP), or indium gallium phosphide (InGaP). Recently, indium gallium nitride (InGaN) lasers have been manufactured on a sapphire substrate using a layer of epitaxially laterally overgrown GaN to match the lattice energy between the sapphire and the semiconductor.
Different tungsten copper mounts were modeled using the finite boundary value solution technique. Performance was compared using 160-W/mK WCu material as the baseline and high-purity copper (thermal conductivity = 398 W/mK) for top-end performance. Based on thermal-resistance reduction, an improvement of 19.1% was obtained for the 200-W/mK material. The functionally graded 320-W/mK material was about 47.54% better, with the top-end material providing a 56.88% improvement over the standard. Corresponding reduction in junction temperature is also shown.
Technical developments using functionally graded materials (FGMs) push the performance envelope of copper/tungsten to thermal conductivity levels around 320 W/mK. This performance level is comparable to the thermal performance provided by copper. These thermal-management solutions are pursued using common, readily available materials such as copper and tungsten.
In addition to traditional heat sinking in packaging of microelectronic dies, more demanding applications are emerging for copper/tungsten (WCu) metal-matrix composites (MMCs) as mounts and submounts for semiconductor laser diodes. Currently, the majority of semiconductor laser diodes are mounted on a mount or submount made out of WCu. Improved thermal expansion match between the heat sink and the die, coupled with the current trend of increasing die size and power-dissipation requirements, has made WCu the material of choice for packaging laser diodes. This is particularly true for die larger than 1000 µm in any direction. Copper/tungsten provides the needed thermal dissipation and good thermal expansion match. Some laser diodes are mounted directly on oxygen free high purity copper, on a beryllia or aluminum nitride ceramic substrate, or even on a diamond substrate.
The majority of power semiconductor laser diodes manufactured for wavelengths in the 800 to 1550 nm range have benefited from the improved performance of the new WCu heat sink bases. Applications include medical, scientific, and fiberoptic-based communication networks, among others.
Copper Tungsten Mounts Changing Conventions
Conventional copper tungsten heat sink bases provide thermal conductivity between 170 and 220 W/mK and a reduced coefficient of thermal expansion that matches the semiconductor dies for diode manufacturing (5.6-9.0 ppm/°C). Laser dies are typically built on gallium arsenide (GaAs) substrates using processes such as molecular-beam epitaxy or metal-organic chemical-vapor deposition. The final chemical composition may include indium gallium arsenide (InGaAs), indium aluminum gallium arsenide (InAlGaAs), aluminum gallium arsenide (AlGaAs), indium gallium arsenide phosphide (InGaAsP), or indium gallium phosphide (InGaP). Recently, indium gallium nitride (InGaN) lasers have been manufactured on a sapphire substrate using a layer of epitaxially laterally overgrown GaN to match the lattice energy between the sapphire and the semiconductor.
Different tungsten copper mounts were modeled using the finite boundary value solution technique. Performance was compared using 160-W/mK WCu material as the baseline and high-purity copper (thermal conductivity = 398 W/mK) for top-end performance. Based on thermal-resistance reduction, an improvement of 19.1% was obtained for the 200-W/mK material. The functionally graded 320-W/mK material was about 47.54% better, with the top-end material providing a 56.88% improvement over the standard. Corresponding reduction in junction temperature is also shown.
Technical developments using functionally graded materials (FGMs) push the performance envelope of copper/tungsten to thermal conductivity levels around 320 W/mK. This performance level is comparable to the thermal performance provided by copper. These thermal-management solutions are pursued using common, readily available materials such as copper and tungsten.
Tungsten Copper Electrical Contacts
The high Electrical & thermal conductivity of copper are combined with the arc-resistant & non-welding properties of tungsten or their carbides to form an extensive series of compositions each designed to give the best performance for your particular application. These materials are used for such heavy duty contact applications as:
Circuit breakers, air & oil immersed
Arcing tips or arc runners
Make & break contacts
Heavy duty conductors, relays & switches.
The high electrical and thermal conductivity of tungsten copper alloy allows a cool, effective transfer of power, while the excellent arc-resistance properties of tungsten copper minimize arc erosion and transfer problems. These characteristics can be varied by composition more silver or copper yields higher electrical and thermal conductivity, while a higher refractory metal content results in superior arc erosion properties. We offer a variety of composites to meet your demands. Regardless of the environment (oil-filled devices, air and gas circuit breakers, contactors, high voltage switch gear) or the application (arcing contacts and plates, arc runners, current carrying members and blade facings), you won't be disappointed in electrical contacts made from our copper tungsten composites.
We will analyze your application & recommend sintered materials to suit your requirements. We can often suggest design revisions that may improve the performance of the product & reduce your costs.From simple to complex geometry, Chinatungsten produces custom electrical contacts that meet the demands of customer applications. A variety of shapes and sizes for contact requirements are possible because of powder metal technology.
Circuit breakers, air & oil immersed
Arcing tips or arc runners
Make & break contacts
Heavy duty conductors, relays & switches.
The high electrical and thermal conductivity of tungsten copper alloy allows a cool, effective transfer of power, while the excellent arc-resistance properties of tungsten copper minimize arc erosion and transfer problems. These characteristics can be varied by composition more silver or copper yields higher electrical and thermal conductivity, while a higher refractory metal content results in superior arc erosion properties. We offer a variety of composites to meet your demands. Regardless of the environment (oil-filled devices, air and gas circuit breakers, contactors, high voltage switch gear) or the application (arcing contacts and plates, arc runners, current carrying members and blade facings), you won't be disappointed in electrical contacts made from our copper tungsten composites.
We will analyze your application & recommend sintered materials to suit your requirements. We can often suggest design revisions that may improve the performance of the product & reduce your costs.From simple to complex geometry, Chinatungsten produces custom electrical contacts that meet the demands of customer applications. A variety of shapes and sizes for contact requirements are possible because of powder metal technology.
Tungsten Copper for Low Voltage Electrode Contact Application
Low Voltage Electrode Contact Application-1
Automotive electrical contacts
Car electrical contacts are typically pure tungsten rod cutting, brazed tungsten the surface oxide layer, if long-term placement will produce automotive electrical failure phenomenon tungsten copper alloy rod to ensure that the contact has good electrical conductivity, resistance to arc erosion and oxidation-resistant performance.
Low Voltage Electrode Contact Application-2
Medical equipment with discharge board
The human crusher, pulse ray generator equipment in high-voltage, high-current discharge electrodes, tungsten copper alloy with copper one way of making, not only to ensure good electrical conductivity of the electrode, arc erosion resistance, and solve the electrodes connectivity issues.
Low Voltage Electrode Contact Application-3
The Overall Electrical Contacts
The arc current 380V contactors, switches, etc. used finger brazing copper and contacts connections occurred often in the process of using high temperatures lead to melting of the brazing layer to produce U-turn phenomenon. Tungsten copper produced by the method of the overall sintered integrally arc contact means to solve the above problems, and to reduce the production processes.
Low Voltage Electrode Contact Application-4
Other applications
Tungsten-copper alloy has a high melting point, high electrical conductivity and good ablation resistance; it can be used in many electrical fields.
Automotive electrical contacts
Car electrical contacts are typically pure tungsten rod cutting, brazed tungsten the surface oxide layer, if long-term placement will produce automotive electrical failure phenomenon tungsten copper alloy rod to ensure that the contact has good electrical conductivity, resistance to arc erosion and oxidation-resistant performance.
Low Voltage Electrode Contact Application-2
Medical equipment with discharge board
The human crusher, pulse ray generator equipment in high-voltage, high-current discharge electrodes, tungsten copper alloy with copper one way of making, not only to ensure good electrical conductivity of the electrode, arc erosion resistance, and solve the electrodes connectivity issues.
Low Voltage Electrode Contact Application-3
The Overall Electrical Contacts
The arc current 380V contactors, switches, etc. used finger brazing copper and contacts connections occurred often in the process of using high temperatures lead to melting of the brazing layer to produce U-turn phenomenon. Tungsten copper produced by the method of the overall sintered integrally arc contact means to solve the above problems, and to reduce the production processes.
Low Voltage Electrode Contact Application-4
Other applications
Tungsten-copper alloy has a high melting point, high electrical conductivity and good ablation resistance; it can be used in many electrical fields.
Tungsten Copper for Switch
Tungsten Copper for Switch
The circuit breaker is one of the systems the most important of the high-pressure equipment. When systems failure, to trip the circuit breaker protection devices excision of failure to maintain system stability. The circuit breaker in accordance with its interrupter media sub-divided into the oil circuit breakers, compressed air circuit breakers, vacuum circuit breakers and SF6 circuit breakers. Oil circuit breaker is divided into two types of oil and less oil. Products are eliminated more oil has basically not used; less oil circuit breaker is not to say that in our country there is a certain range of applications, but this performance is very good, but relative to the same voltage level of vacuum its cheaper price and s breaker can basically meet the requirements, the specific use down. Oil circuit breaker has a fatal flaw, it is in the long-running the insulating oil prone carbonation phenomenon, especially in the case of a short time repeated resection failure are more likely to insulating oil carbonization, which will greatly reduce its ability to interrupter. The second is the maintenance workload, maintenance interval shorter in the new project is not recommended to use.
Compressed air circuit breaker must be equipped with a compressed air device, relying on compressed gas interrupter larger area and greater wear contacts, and therefore a very small range of applications. The vacuum circuit breaker is a vacuum (pressure of l0 ~ l0-6 Pa) to the interrupter of a circuit breaker, the contact is mounted in the vacuum interrupter chamber. Since there is almost no free gas in the vacuum, therefore, when such contacts of the circuit breaker in the disconnected only emitted because of the high electric field, and the thermoelectric emission produces little vacuum arc so that it can in the first current zero crossing off, so that both ensures that the interrupter can be within a very short time, but not so in the system to produce a high pressure changes due to the Shaanxi speed current. Vacuum circuit breaker has small size, light weight, fast action, long service life, high security and reliability, and eases of maintenance overhaul many advantages, but the price is more expensive than oil circuit breaker. SF6 Circuit Breaker is the use of a circuit breaker of the SF6 gas as the insulating and arc extinguishing medium, s is a colorless, odorless, non-toxic and flammable gases, its chemical properties are fairly stable below 150 ℃, although at a high temperature will break down to produce toxic gas interrupter state, and will produce a small amount of the active substance, but through the use of the adsorbent and the contact has a self-cleaning function, equipment and personal will not cause harm.
The circuit breaker is one of the systems the most important of the high-pressure equipment. When systems failure, to trip the circuit breaker protection devices excision of failure to maintain system stability. The circuit breaker in accordance with its interrupter media sub-divided into the oil circuit breakers, compressed air circuit breakers, vacuum circuit breakers and SF6 circuit breakers. Oil circuit breaker is divided into two types of oil and less oil. Products are eliminated more oil has basically not used; less oil circuit breaker is not to say that in our country there is a certain range of applications, but this performance is very good, but relative to the same voltage level of vacuum its cheaper price and s breaker can basically meet the requirements, the specific use down. Oil circuit breaker has a fatal flaw, it is in the long-running the insulating oil prone carbonation phenomenon, especially in the case of a short time repeated resection failure are more likely to insulating oil carbonization, which will greatly reduce its ability to interrupter. The second is the maintenance workload, maintenance interval shorter in the new project is not recommended to use.
Compressed air circuit breaker must be equipped with a compressed air device, relying on compressed gas interrupter larger area and greater wear contacts, and therefore a very small range of applications. The vacuum circuit breaker is a vacuum (pressure of l0 ~ l0-6 Pa) to the interrupter of a circuit breaker, the contact is mounted in the vacuum interrupter chamber. Since there is almost no free gas in the vacuum, therefore, when such contacts of the circuit breaker in the disconnected only emitted because of the high electric field, and the thermoelectric emission produces little vacuum arc so that it can in the first current zero crossing off, so that both ensures that the interrupter can be within a very short time, but not so in the system to produce a high pressure changes due to the Shaanxi speed current. Vacuum circuit breaker has small size, light weight, fast action, long service life, high security and reliability, and eases of maintenance overhaul many advantages, but the price is more expensive than oil circuit breaker. SF6 Circuit Breaker is the use of a circuit breaker of the SF6 gas as the insulating and arc extinguishing medium, s is a colorless, odorless, non-toxic and flammable gases, its chemical properties are fairly stable below 150 ℃, although at a high temperature will break down to produce toxic gas interrupter state, and will produce a small amount of the active substance, but through the use of the adsorbent and the contact has a self-cleaning function, equipment and personal will not cause harm.
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