One hot technology Quest: Unraveling the true veil Ⅱ of hybrid hybrid technology is also fair to
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inscription: < br> How your mind the impression of hybrid: the weight load than the full weight of the prototype car is heavier? low-end price of hybrid vehicles in the high end than the non-hybrid car is more expensive? have the money I can afford enough expensive oil money, but also buy hybrid? do not fuel-efficient hybrid vehicles? energy-efficient hybrid vehicles mainly in the braking energy recovery point? any car manufacturers to produce hybrid vehicles? If so, I can clearly tell you: you are varied, according to the current relatively high degree of public acceptance of the classification methods are mainly two: one is in accordance with sub-structure: in series, parallel and hybrid hybrid. the other is classified according to degree of hybridization. Whether classification to conventional hybrid vehicles mainly includes three parts: power generation plant, power storage devices and power transmission equipment. First, I introduce the next three parts, let everyone know that the energy transfer is what the chain, then this Each link chain, respectively, as a whole, energy analysis and the energy flow analysis, to distinguish between primary and secondary, so that everyone at a glance.
power generating device
a wide range of power generating device, the current major is the engine we all know, gasoline fuel engines, diesel fuel engines and a variety of hybrid fuel engine. Because many of these presentations, in which no detail, we introduce other less common under the power generation devices: rotary engines, gas turbines, two-stroke engines, Stirling engines and fuel cells. present study compared the new engine include: linear free piston engine or the engine will be called to make presentations in the future.
rotor engines have a small size, light weight, warm-up speed quickly and the torque curve flat, etc. advantages in the use of hybrid cars is the emissions of the main problems, especially in the switch mode emissions, while the minimum fuel consumption rate is relatively high, reaching 300 ~ 360g/kwh. but for some hybrid vehicle design terms or meet the performance requirements. Mazda to a subsection on the application of hybrid rotary engines.
transient response time of long gas turbine itself does not apply to automobile transmission. but in the hybrid electric car, the engine and may only drive a small generator speed range, so no problem of gas turbine shortcomings. And the use of gas turbines will have some advantages, such as small size, low maintenance cost, noise and vibration at low speed can produce greater torque. thermal efficiency, can be a variety of fuels and simple design. In addition, the gas turbine is outboard engines, the emission level is low, and after the processor or through the use of catalytic combustion chamber can also be used to achieve quasi-zero emission levels. But in the present application, little car, but the literature describes, it has applications in a mixed potential on the Series and can be mass-produced and low cost, I believe its future prospects will be better. < br> For the two-stroke engine used to drive the car most of the research is very basic, some studies have looked at the engine intake and exhaust cycle used in a variety of scavenging ways to improve fuel consumption and reduce hydrocarbon emissions from the engine, trying to fluid mechanics as a way to improve engine design, and some studies have looked at ways to improve the combustion of the combustion process, some research studies focus on the work of EFI, is generally believed that, with low fuel consumption and low-emission two-stroke engine system relatively complex structure. But hybrid cars are easier to achieve on, because the hybrid car engine running in a relatively narrow torque - speed range, most of the water-cooled two-stroke motorcycle engine can be used for hybrid electric vehicles, they do not exist package, but high-load conditions of the NOx emissions is a potential problem, and usually of small motorcycle engines to meet emissions, noise, cooling and car engine fuel consumption parameters and the requirements are very different, so to give full play to the potential of two-stroke engines also do a lot of hard work.
Stirling engine heat as high efficiency, low emissions and low noise performance make the It can be used in hybrid vehicles. but because of the Stirling engine is external combustion, so it has low power density and the need for large heat sink and other shortcomings, and the Stirling engine has not set a precedent in the automotive industry. by the U.S. Department of Energy The pre-launch research showed that the engine, the Stirling engine dynamic performance is poor and ordinary vehicles is difficult to match the transmission system, while the series hybrid electric vehicle is not a problem, so the engine may also be in application of hybrid cars.
power storage device power storage device to understand is the longest electrochemical cell, followed by a flywheel battery, super capacitors, fuel cells will be some people down to storage devices. This is classified as power generating devices. < br> electrochemical cell, also known as battery. in electric vehicles already on the application of considerable experience, including considerable potential for several applications, including lead-acid batteries, nickel metal hydride batteries and lithium ion batteries. At present, the ratio of lead-acid batteries for driving energy is generally 30 ~ 40wh/kg, than the power is generally 150 ~ 200w/kg, cycle of life is generally 500 to 700, in hybrid cars on the advantages of using lead-acid battery: lead-acid battery technology is more mature, high reliability, easy to get and cheap raw materials in a wide range of applications on electric vehicles so that it has also considerable experience in applications, but lower than the energy of lead-acid battery in discharge and overcharge, their life will be significantly reduced, the depth of discharge and temperature change is also a greater impact on battery performance, lead-acid batteries in the future development goals to improve the specific energy, increased cycle life, to further reduce costs, the development of sealed maintenance-free battery. thin plate VRLA acid batteries due to high peak power, can achieve shallow discharge cycles, and maintenance is very suitable for hybrid vehicles use nickel-metal hydride batteries are extremely nickel oxide, hydrogen carrier is extremely negative hydrogen storage alloy which has good resistance to over charging characteristics of a good safety and the use of charge-discharge efficiency is more important is that the battery is no dissolution of the reactant precipitates developed by Japan's Matsushita Battery Industrial Ni-MH battery charge capacity of 6.5Ah, each unit's maximum output power of the battery 100w. Ni-MH battery discharge power of 2 seconds 600w/kg, discharge power is more than three seconds 500w/kg, for the control of hybrid vehicles is very beneficial addition Ni-MH battery charging almost 100% efficiency, is conducive to mixed electric vehicle regenerative braking, taking into account the hybrid electric vehicle battery is fully charged and the maximum is characterized by incomplete discharge, discharge and recharge the battery often in a state of energy consumption and is often added, may have a certain impact battery life But experiments show that these factors affect the nickel-metal hydride battery life is not large, this also shows that hybrid vehicles use nickel-metal hydride batteries will be very appropriate, therefore, Japan's hybrid vehicles listed on civilian vehicles, nickel metal hydride Battery dominant. experts predict the future period of time, Ni-MH battery is the most competitive, but the domestic used car large Ni-MH battery technology and cost issues still a major difficulty, however, an ongoing research in this area and the corresponding support of the State, I believe that soon there will be the higher cost of domestic vehicle nickel metal hydride batteries. lithium-ion battery energy density can be achieved 100wh/kg, power density 300w/kg, and long cycle life, in the Mitsubishi Motors sedan-type self-generation electric vehicles SPACE, WAGON and card models have already been applied CANTER. In addition, the United States, Japan also are developing lithium polymer batteries. has been put into the security of critical experimental assessment, the United States USABC planned for 2000 to 2010 developed a specific energy than the power of 400w/kg 200wh/kg lithium polymer batteries, to address the problem of high prices, looking for cheaper, suitable active substances. current lead-acid battery has been very little use, mainly using a nickel-metal hydride batteries and lithium batteries.
flywheel battery, also known as electrical machinery batteries. It breaks through the limitations of chemical batteries, using physical methods to achieve energy storage, flywheel battery has a motor, charging The form of the motor to the motor operation, driven by external power supplies, motor drives high-speed rotating flywheel, the flywheel power to charge the battery. that increases the speed of the flywheel to increase its kinetic energy. discharge, the state of the motor generator operation, in flywheel driven by exporting electricity to complete mechanical energy, kinetic energy, to electrical energy conversion, flywheel, flywheel battery is operating in a vacuum, the speed of up to 200,000 r / min, but it also constitutes a proposed strength of the material density ratio a higher demand. In addition, the flywheel battery with 2 ~ 4kw/kg 125wh/kg than power and specific energy, and virtually maintenance free, has a lower life cycle cost, so that is very suitable for heavy-duty hybrid truck transmission of energy storage components. At present, difficult to promote the application of flywheel batteries because of its high price and the use of safety and reliability of the process can be.
super capacitor applications in hybrid cars on the most attractive features is that it has high specific power up to 2 ~ 4kw/kg and high cycle efficiency up to 92 ~ 98%, including working conditions, including peak power, which power the vehicle to accelerate recovery and avoid braking system over voltage condition is of great significance. In addition , as a super capacitor with stored electronic and no physical changes in the chemical reaction can be, with excellent tolerance and life cycle of work, but the application of a super capacitor main defect is relatively low specific energy, currently about 7 ~ 10wh / kg. because the super-capacitor voltage varies directly with the state of charge, the majority of its capacity may not be used, therefore, suitable only for super-capacitor energy demand is low compared with mild hybrid vehicles, the Russian experts also pointed out that in the light mixed vehicles on the use of capacitor energy storage device will be more reasonable.
energy storage capacity of the solution to many: I believe that two more feasible now.
first is a composite power:
as batteries and super capacitors can not meet the needs of vehicle power and energy, a combination of the two to form a composite power, to give full play to their respective battery and super capacitor specific energy and power advantages of the composite power structure including batteries, super capacitors and the control of a super capacitor charging and discharging of the power converters DC / DC. composite power of the significance of the following:
through a combination of complex power, the battery only provides vehicle electrical system during operation, the average power, average power super capacitor charge to make up fluctuations than the power demand. by super capacitor The application of advantage, so the two combine, exceed and maximize the recovery of vehicle braking energy, to further tap the HEV energy saving, emission reduction potential. through the composite power supply of the battery manufacturers to devote more energy for extended battery life, reduce battery costs will help to further improve battery performance and reduce battery costs. As super capacitor was relatively easy to accurately estimate the battery SOC can provide a new solution. As a super capacitor has a strong high and low temperature performance, and its influence by a lesser extent, ambient temperature, you can use this feature to adjust the control strategy, increased the proportion of super-capacitor charge and discharge, to ensure vehicle performance under low temperature requirements.
second battery industry is subsidized state monopoly.
power storage device through the analysis, we all know, the battery life is , the hybrid electric vehicle because the engine, not all energy has to go through stored before use, so battery life can be longer still, for the pure electric car is a very serious problem, the battery wearing, good charge and discharge more than a thousand times corrupt, not to the charge and discharge hundreds of times out, so that people take up this part of the cost, no one is willing.
there is a problem, charging will take time. Now we drive to the gas station, a few get away So, we believe that easy to drive, if the fuel is now a day, and then add the oil can only run one hundred kilometers, will you? necessary or not. may we all do not want to drive, the electric car is faced with such embarrassment.
There is a third problem, the battery scrapped three years or five years, how do the old batteries? user how to deal with? people may say that the automobile manufacturers to recover, the problem again, and now production of hybrid cars, pure electric vehicles have several companies that own production company is the battery? FAW production of the battery? SAIC production of the battery? all. They recall how to deal with? battery pollution emissions compared to the pollution problem, I think it may be it will be more severe.
how to solve, I think the energy saving, low-carbon life is our government to promote that everyone should be implemented. But this duty can not measure. so not enforceable. I do not buy conventional vehicles buy pure electric cars, hybrid cars are my thing, do not break the law thing. taking into account the recent State of the electric car subsidies, I would like to say that a European policy of the country's new energy vehicles. The cars in China last year had a special study of all reported that in Switzerland, the new energy policy of the car, they set up a fixed charging station, charging all of the new energy vehicles for free. That means you bought a conventional car, then you can run out of petrol. But to buy a new energy vehicles, as long as you buy the vehicle out of the initial money to run. for to do is you will seriously consider it. Besides Texas, under the policy, I have not witnessed last year, Texas A & M University, Gao Yimin Professor, introduced in China, the other side of hybrid car buyers can enjoy the treatment in the school bus. better than the domestic side of the school bus, with accompanying with the stop, other vehicles, the privilege of priority it first. It is also tempting. China now is the car allowance. I repeatedly thought, this subsidy, regardless of the number, I do not dare to buy. the prices of enterprises will be, the total subsidy money will not feel real benefits to themselves. I guess there is this idea I'm not the only one. If you do not believe, you look out of electric vehicles, hybrid vehicles have several people in their own vehicles in the open. or from another point of view, people developing their car subsidies to buy a pure electric car yet? apparently attractive enough.
energy saving, I start, of course, very noble, noble We also want to be affordable, the policy can be a long time. My personal recommendations are as follows: state monopoly grants the battery industry, the state lose money operating the battery industry so that use tax money on the one hand, energy conservation, pollution, the obligation to implement low-carbon life to every man enforceable. On the other hand the unity of the battery recycling, help to avoid secondary pollution. deeper level terms, the state of the battery production, use, management, infrastructure and power together, by way of a user can effectively promote more people to purchase and use of new energy vehicles. effective way is: because the batteries in a vest an enterprise, users need only pay a certain annual fee to the company, you can use the battery of the enterprise, the enterprise can always a lot of battery charging, the battery is dead the user to pick the battery, just to the car electrical energy consumption do the battery to cancel and replace the power station has been filled with energy of the battery can immediately walk. and fuel than the original, there is no time to waste.
Some may say that this will be difficult, in fact, no trouble, we pumping the gas is not oil from the oil wells plus Well, something happens to the fuel delivery to a gas station, then add it to us. a battery charge, then change to give us a reason.
remember the power transmission device honor and a FAW Engineering Institute recognized at a banquet in his hours of work early, enroll in a Ph.D. later, the door division be alumni, and his main research direction is the development of diesel engines, about the direction of my research, I said that is a hybrid car, he suddenly rather scornful tone, said hybrid vehicle no technical content, the concept of pure speculation. I was raised up to fight all of a sudden, relied fearless spirit, and his On the Road. First of all I say mixed really fuel efficient vehicles. He agreed, and I said as long as the fuel, there is Development. temporarily that battery technology content, traditional vehicles, the province is a difficult to control, plus motor hybrid cars now, both directly coupling are a headache from the principle, let alone on the actual operation of the process. In particular, electric wheel hybrid vehicle. so it has a technical content.
In addition, another point of view, it is not only meaningful, technical content, vehicles and is a necessary step in the future. If the oil has always existed, and whether it is gasoline, diesel oil, peanut oil, soybean oil Han, are can be used in the car. conventional vehicles burning these fuels do not burn these hybrid cars fuel economy, pure electric car without burning the fuel, so the hybrid car is necessary. Moreover, if we do not have fuel, and rely on pure electric vehicle drive motor! hybrid cars we drive is the motor. study of hybrid car is necessary and has a long-term significance. This shows that the research is very interesting powertrain.
After characterization, I believe that there are five ways that more fully explains the hybrid nature:
first hybrid vehicles can reduce engine size and weight
conventional vehicles because of engine to meet the vehicle acceleration, hill climbing and high speed performance requirements, often with large reserves of power. from the name can be seen, this usually do not use some power. the characteristics of hybrid energy source is more, it has both engines, there are motor, battery, low speed, it does not need engine, high-speed or hard acceleration, climbing the motor, battery and engine together work. battery reserve power can be disguised to replace the traditional reserve of the vehicle engine power, and this part of the reserve power in the vehicle at low load when the power demand can also be elegant and low emissions profile to show up, show than the original engines more excellent features. It would appear that the engine does not require reserve power, and can be made into a low-power engine, he any good? the one hand because of reduced emissions, the volume decreases, we all know that the addition of the motor, battery, hybrid vehicles must increase their size, will occupy the user can use the space, the engine side will have compensation reduced in size. related series of volume decrease. On the other hand, decreases the weight of volume decrease led , narrow cylinder, cooling system, lubrication system and a series of institutions and systems are reduced, reducing the vehicle's weight. Compared with the right battery, hybrid motor is concerned, the quality of the vehicle will not be re- too much. quality and fuel consumption is directly related to weight means the car is not fuel efficient too.
its second hybrid vehicle engine optimization can improve
then analyze the characteristics of the engine characteristics to gasoline as an example the engine's fuel consumption curve is typical of the hook curve. probably in the vicinity of seventy-five percent, with the lowest fuel consumption. Each engine is slightly different. the lowest point of the efficiency of the fuel consumption of gasoline is about 25% of the vicinity. usually work vehicles area about how much load is 20% of the books, in my opinion, the city is about 10%. This is What is the efficiency, around 8%. That is a car, regardless of the salesman told you that you how much energy the gasoline engine, its efficiency is not likely to exceed 30%, usually at work efficiency as low as 10%, the engine has two advantages in this respect: first, my own reserves of power to eliminate the use of a small row the amount of my usual load is 75%, to avoid a small horse-drawn carts, horse-drawn my car right now, the efficiency of natural increase. Some people may say, or just start at low speed, the load is still very small thing, is not a problem, a battery, motor ah, when their work. engine does not work, avoid the low efficiency area.
Some people may joke that I do not know the logic, the battery's energy comes from the engine, originally used directly for the vehicle power, but also more energy transfer of two components: batteries, motors, efficiency is reduced. through the battery, motor, energy is lost, I admit that this will question not only the ordinary layman, and even some professors challenged me once . but I came to an account balance.
low-load efficiency of 10%
low engine load using the battery, when the efficiency of motor drive:
Ni-MH battery charge and discharge efficiency: 95% * 98% , permanent magnet synchronous motor efficiency 98% and charging 30% high efficiency engines, three multiplication, 95% * 98% * 98% * 25% = 22.81%> 10%
they still fuel-efficient . so this part of the engine work in the area can save a lot of fuel efficiency.
characteristics of the third hybrid vehicle can very simply by optimizing the engine itself to meet the
this main point is that the advantages of hybrid dual-energy, on a section is how optimized the engine itself, this section mainly to explain the type of engine optimization. from the front part of the power generating device can be seen, the choice of hybrid, more and more applications in the vehicle had not appropriate now because the engine multi-hybrid electric vehicle energy source characteristics, is now available. What good is it? a good point on the section that the efficiency of gasoline is 30%, 40% of diesel engine does, that can optimize both the number of percentage points, most of the energy wasted, and this is the engine of the disadvantages of current energy sources are flawed, is very serious. now in the room for big election, we face many kinds, and efficiency go up. As the next step which has a about these specific topics, so temporarily detailed, but must be clear, this part is another energy-saving hybrid car key.
fourth hybrid vehicle to re-use braking energy
this part of the energy recovery of all understanding of hybrid cars people can say, of course, part of the energy does allow us to have part of the energy-saving, energy-efficient vehicle when we left without when we need to consider all the possible places to cut costs.
but This part of the amount of energy can bring much effect? We did an experiment, do not say this Which car experiments ,2-6%, this is a very good effect. Another point I can not confirm the early stage friends asked me why did this article come out, in fact, I was checking out a law, European law, and it has not found, so this hearsay it, reportedly for a European vehicle safety laws, prohibiting the use of braking energy recovery way to achieve energy-saving effect.
Some experts may be engaged in the rest of your life brake energy recovery, say you took me a few words to deny Hua-Jie Ding, and callow Xiaomao Children braking energy percentage of the total energy you know ? In fact, the teachers worked on hybrid may have in mind. give you an example, the campus is quieter, the Department of age in some of the professors on the body is not very good, always liked wandering around the campus. a system where we met Professor Liu, a walk, talked the way, the did not think he was indignant: before walking on campus is very safe, even if a car is also very civilized. which as now, a bunch of laboratories engaged in hybrid, driving a test car around run, if program fly, can not brake how to do? I'm just a perfunctory process that we do, so do the number system to the redundant system. very safe and the like, in fact, I do still have to test vehicle lab Several characters on the front identifies the Toyota pedals as to say things out of the recall and improve it, the meaning of life because of the heavy and should be more treasured. deviate from the theme of the.
fifth hybrid vehicle can take advantage of existing hybrid electric vehicles
because of the energy storage and motor and other components, you can use different energy, so that sometimes we look back now is very interesting, we tried to promote electric cars, I do not deny that the future direction of electric vehicles. But we will not discuss energy source, WELL-TO-WHEEL energy conversion efficiency mode, just from the power to the vehicle under consideration, what kind of vehicle the most energy. I dare say that the prevalence of the last century, and now the most energy in Changchun tram there, he two wire a, there is no energy storage, ah, directly to the car to use. the energy chain is short. To do this I do remember last year, a special investigation, but the companies do not match, unable to get detailed data and reports. of course, wired very convenient, so now we are thinking about charging the battery energy, so many people now and then of plug-in hybrid vehicles, also known as Plug-in HEV, of course, there is a reasonable thing, which makes hybrid vehicles and pure electric car one step closer. auto show many hybrid vehicles have become a plug-in hybrid of the Well, and why? from hybrid cars to plug-in hybrid vehicle technology difficulty, very easy to implement. But is feasible, because only the countries and regions.
that needs to be unified from the point of view of energy as a system point of view. that is, the Well-to-Wheel, Chinese is: from the well to wheels. This concept is the fire of speculation the past two years, In fact also, the energy sector, a branch of the vehicle is a small, considering the whole is more scientific. undeniable, pure electric cars is a very good future direction of the car, but now the development is appropriate? abroad has been to develop many a, such as Switzerland. in China's development is appropriate. I think the Swiss development is very appropriate, inappropriate yet of China's development. Swiss development because of his energy structure, mainly clean energy, electricity is how people come from? most green, wind, solar, geothermal and nuclear power is called green. in China it is mainly coal-fired generation, which is thermal power. A few days ago an American professor talked about this part, from the heat value of coal to generate electricity, then send to the grid, and then stored in the battery until the car is used, the efficiency, I am not down, only to note the conclusion of this low efficiency is amazing. not discuss thermal pollution problems, because someone can focus on recovery of pollution Well handled. So the thermal power accounted for under the current composition of the main energy, we have developed plug-in electric or hybrid cars is still too early. It was also questioned, should not be developed that China Well? development! when development? and other Chinese nuclear power, hydropower, wind power and solar energy mix is dominated development.
2008 China's energy structure, as this study can
so, to develop still open to question.
then vehicle as a system for analysis, hybrid vehicles to clear the main source of energy, does not include plug-in hybrid and fuel cell vehicles, it is the main source of the engine. That only change other aspects of this session energy efficiency, and change the engine does the whole system can always change. So R & D focus is the engine. in the next section which I will detail.
four components of hybrid technology as an R & D trends
colleagues made a number of issues need to be explored, the article predicted energy content will be removed this as a topic of the next show to everyone in this state.
Motor vehicle manufacturers develop hybrid prerequisites
I remember this school, a professor talk about the domestic auto companies, mentioned a very famous domestic motorcycle enterprises are prepared to do to enter the automotive industry. The professor was very nose: Do you think cars like you do motorcycle, only tax evasion will be able to do a good job, win the thing in the market. and regardless of the professor's intemperate remarks. a reflection of, or do hybrid cars do have the objective conditions. or more precisely, to have the core of things.
First of all, with the ability of the car the car is
basic conditions for hybrid vehicles. cars are the flower industry, behind automotive industry must have done well, further, hybrid cars are the cars of the flowers, cars do not do a good job hybrid vehicle is impossible. vehicle chassis, engine and vehicle parts is a new energy auto companies want to pursue necessary.
Second, there must be key components of the design and production capacity
this points more difficult to achieve, the key components mean? battery, motor, engine. only the engine, in recent years, the domestic auto companies have been suffering from the national criticism. battery, motor and easy. But having said that, and want new energy vehicles, the world's leading companies, you have to fight tough. grasp the core technology to control their quality and cost of the car. For example: the development of our own to buy a hybrid vehicle's nickel-metal hydride batteries Chunlan, buy 16Ah, they are not related to the battery box matches , and then used a 24Ah box to us, we do not temper, why? Well we do not have this technology. yes, how do we how to design a suitable, but also can use him. In addition, although the inappropriate parts, the price fool you , there is no way ah. especially for the enterprise.
again, have enough capital reserves sufficient reserves
we might have a good understanding of the enterprise, however, estimated that the new energy vehicles is different from the reserve funds conventional vehicles. conventional vehicles can quickly return to you, ah, new energy vehicles were praised in recent years has been. market share is very small. This chain is not long enough funds, even if the technology no matter how good, could not drag the past. < br> These three conditions are indispensable, if you can not meet the first one, you can not make good cars, hybrid cars do not make good, no good car pave the way, what do you eat and what car ah? the lack of a second, then why the price of hybrid vehicles so high, by buying batteries, motors rely on outsourcing, and even some enterprises have purchased the engine. They have to survive in these places, ah, you master the core technology, they also do not know How would you like your car in the end parts, is holding a flute to sell you something ready, you're not technical, only to pay high prices, the result was not easy to use bought. buy a car they will buy when the price is so high, dead-end A. So this is certainly not lacking. Third, it is not good to buy new energy vehicles, we all know, world-wide know but we are all optimistic, most also know that this means that you engaged in has the potential to cause, but the money put into recycling, but may be short-lived fad. Yours very difficult to survive on their own, do not think holding a national Maybe time will the law for you. Therefore, enterprises must have adequate financial support, a company can not, can team up, do not think to buy a motor, batteries, a fight is the new energy vehicles will be able to make money, get worse far from it.
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