Li Huohua and Shen Qihong

　　Recently, a news has become the focus of attention. the Political Bureau of the Communist Party of China (CPC) Central Committee has made a collective study on the development status and trend of blockchain technology, emphasizing that blockchain should be regarded as an important breakthrough for independent innovation of core technology and accelerate the development of blockchain technology and industrial innovation.

　　So what is blockchain technology? What is its development process and current situation? What application scenarios are there in the future? Let’s talk about it here.

　　The Origin and Development of Blockchain Technology

　　When it comes to blockchain, many people may think of Bitcoin. In fact, the two are not the same thing. Blockchain is the underlying technology of Bitcoin.

　　In 2008, a self-proclaimed "Satoshi Nakamoto" published a white paper, hoping to build an electronic money system that won’t be spammed. In January 2009, Bitcoin was officially born, with a total limit of 21 million pieces. The distribution rules are transparent, and there is no central issuer, which is automatically executed by code. The code and operation of Bitcoin are maintained by the participants, and anyone in the world can participate in it.

　　At first, Bitcoin was only circulated among computer geeks. Some people tried it as a new gadget, while others were attracted by its utopian ideal of not spamming and circulating freely. In 2010, there was even a story that a programmer exchanged 10,000 bitcoins for two pizzas. In any case, few people would have thought that bitcoin would have such a great influence later.

　　With the passage of time, bitcoin gradually spread from the computer geek circle. As more and more people participate, capital speculation and speculation follow one after another, and the price of Bitcoin has also started the skyrocketing and plunging mode, which has attracted the attention and reports of some mainstream media and attracted more and more people to study Bitcoin.

　　After studying the code of Bitcoin, people collectively refer to the underlying technology adopted by Bitcoin as blockchain technology, and Bitcoin is the first application of blockchain technology. If bitcoin is compared to bread, then the blockchain is flour. Flour can be made into bread, noodles, rolls, steamed bread and cakes. Similarly, you can use blockchain technology to create bitcoin, and you can also use blockchain technology to do many other things to benefit the whole society.

　　Blockchain is a "trusted machine"

　　As the name implies, blockchain is a combination of "block" and "chain", which is essentially a distributed account book. So, how does this account book keep accounts and how does it work? We might as well use an analogy to illustrate.

　　At the beginning, a group of people first stood up and took a blank piece of paper for bookkeeping, and the system gave this bookkeeper a certain amount of reward (such as 50 bitcoins). After recording the bill, generate an anti-counterfeiting code from this page of bill through encryption algorithm, and copy the bill to all other people at the same time. Next, by calculating a difficult problem, the person who works out first can keep accounts and enjoy the rewards given to the bookkeeper by the system. When recording the bill on the second page, you need to write the anti-counterfeiting code of the bill on the first page at the beginning, and then make an account. After recording, you can also generate an anti-counterfeiting code of the bill on the second page through encryption algorithm, and then copy the bill to everyone else. Then, everyone will compete for the right to charge the bill on the third page by calculating the next difficult problem. This bill will also be marked with the security code of the bill on the first page, and after recording, it will also generate an security code and synchronize the bill to others, and so on. This page-by-page bill is turned into an increasingly thick general ledger through the binding line in sequence, and each participant has one copy.

　　In the above analogy, the bill page by page is called a "block" and the binding line is a "chain". By binding the bill page by page in sequence into a general ledger, a "blockchain" is formed, and its essence is still an account book. Only this account book has one person, and there is no central person or organization. Everyone is equal, and everyone can compete for the right to keep accounts by calculating difficult problems. The whole account book is jointly maintained by all participants.

　　Since there is no central person or organization, how can this jointly maintained account book prevent malicious people from making false accounts or tampering with account book records? Suppose Zhang San grabbed the right to charge the bill on page 100. His good friend Li Si had only 3,000 yuan in his account, but Zhang San helped him secretly change it to 30,000 yuan. After recording the account, he synchronized the account book to others. At this time, others will immediately find that there is something wrong with this account, because there is one account book, and the ins and outs of Li Si’s assets are recorded in the previous account book. Therefore, others will refuse to add the bill on page 100 with wrong records to the general ledger, and will choose another honest person to record the bill on page 100 through calculation problems.

　　Therefore, we can see that blockchain technology has these characteristics: openness and transparency (everyone has one account book, everyone can check it), decentralization (there is no central person or organization), and it cannot be tampered with (because any tampering or false accounting will be discovered).

　　In daily life, many people are used to paying with WeChat and Alipay, and WeChat and Alipay act as bookkeepers. We need to trust this bookkeeper not to misremember or falsify accounts. Blockchain is different. Hackers may attack and modify the account books in a computer, but if they want to really modify the blockchain data, they need to attack more than half of the account books in computers, which is very difficult, especially in a blockchain like Bitcoin. There are tens of thousands of accounting nodes, and one account book is distributed all over the world. Therefore, blockchain technology also has great advantages in security.

　　Openness, transparency, decentralization and non-tampering … … Because of these advantages, the famous British financial magazine The Economist praised the blockchain as a "machine of trust".

　　Blockchain empowers future social development.

　　For more than a decade, blockchain technology has gone from the 1.0 era to the 2.0 era, and now it is moving towards the 3.0 era.

　　In the 1.0 era of blockchain, Bitcoin is a typical representative, mainly recording transaction information simply, with very single function and limited application scenarios. In the 2.0 era of blockchain, the Ethereum project is a typical representative. Different from bitcoin with single function, Ethereum has added the function of "smart contract", which can be simply understood as a program that can be automatically executed. Because of this automatic program, the blockchain has been upgraded from a single-function account book to a world computer, on which people can develop various blockchain applications.

　　As for the 3.0 era of blockchain, just like the 5G era, only after it really comes can people know what it looks like and what new business models and social impacts it will have. The blockchain we are talking about now empowers social development, mainly based on blockchain 2.0.

　　So, in what ways will the blockchain empower social development?

　　The first is the financial industry. The financial industry has to deal with all kinds of accounts every day. The blockchain is essentially a distributed ledger. Using the blockchain as a "trusted machine", it has obvious advantages to use blockchain technology to realize the work that needs multi-party information synchronization, such as bookkeeping, accounting, reimbursement, settlement and tax return. On August 10th last year, Shenzhen Taxation Bureau and Tencent Company launched the blockchain electronic invoice, which realized that the electronic invoice can’t be forged, the data can be inquired, the transaction can be invoiced, and the invoice can be reimbursed, which greatly simplified the traditional financial and taxation workflow.

　　In addition, cross-border payment is also a major application of blockchain in the financial field. Using the advantages of blockchain technology, such as openness, transparency, non-tampering, and distrust of intermediaries, various cumbersome procedures between different banks can be reduced and the process can be accelerated in cross-border payment. On June 25th last year, Alipay launched the cross-border remittance service of e-wallet based on blockchain in Hong Kong. With the Hong Kong version of Alipay, cross-border remittance can be made to Philippine wallet Gcash through blockchain technology. At the press conference, the whole remittance process took only 3 seconds, while it took several days through the traditional cross-border transfer method.

　　In addition to the financial sector, blockchain technology is also promising in business. JD.COM launched the JD.COM Zhizhen Chain a long time ago, using blockchain technology to build an anti-counterfeiting traceability platform, recording the important data of every link of goods from raw material procurement to after-sales, and jointly cracking down on counterfeiting with regulatory authorities, third-party institutions and brands. Last year’s Double Eleven, Tmall International Mall had more than 150 million cross-border goods, which made use of the traceability and non-tampering characteristics of blockchain technology to achieve permanent traceability, prevent false information and protect consumers’ rights and interests.

　　In the field of people’s livelihood, the application prospect of blockchain technology is also very broad. For example, charity can use the openness and transparency of blockchain technology to monitor the flow of each charity fund and ensure that the money finally reaches the recipients.

　　Blockchain technology can also simplify government affairs and realize the interconnection of various functional departments. On November 13th last year, Loudi City, Hunan Province issued the first real estate blockchain electronic certificate, which realized the interconnection between real estate registration and the data of government functional departments such as land, taxation and real estate.

　　Storing data on the blockchain also has legal effect. On June 29 last year, the first case of blockchain deposit in China was pronounced in the first instance of Hangzhou Internet Court, which confirmed the legal effect of using blockchain technology to deposit electronic data and clarified the review and judgment methods of blockchain electronic deposit.

　　For many people who pay attention to privacy protection, blockchain technology is a great boon. All kinds of usage data we leave on the Internet every day, including sensitive information such as identity, mobile phone number, hobbies, shopping records, location, etc., may be leaked directly or indirectly, which will bring great threats and troubles to our lives. Blockchain technology combines cryptography and encryption technology, which can realize the separation of user identity and data, encrypted storage and distributed storage, and make your own data completely in your own hands.

　　The current blockchain technology is still in the early stage of development, just like the Internet around 2000. Although it is full of various possibilities, it is not mature, and there are very few successful large-scale applications, and it is also full of capital speculation and speculation. For this emerging technology, we can’t overestimate its short-term impact, nor can we ignore its long-term changes.

　　(Zhan Rongrong, Lu Bufan, Ma Dan and Wu Jie also contributed to this article. Special "Vernacular Blockchain" contributed by WeChat official account)

　　Overseas networkAugust 23 rdOn August 1st, two French hip-hop singers, Booba and Kaaris, fought at an airport in Paris and were detained by the police. Although they are temporarily detained in prison, netizens are surprised to find that they are still active on social networks, which makes people question how they play with their mobile phones in prison. In fact, it is nothing new for French prisoners to secretly hold mobile phones in prisons.

　　According to the French newspaper le figaro, on August 1st, Booba and Kaaris, two French hip-hop singers, and their entourage fought in orly airport, causing flight delays and scaring other tourists, and two of them were slightly injured in the group fight. Finally, the two singers and their entourage were detained by the police. The airport filed a complaint against them on the 2nd. Booba is currently being held in a prison in Essonne province, while Kaaris is being held in Fresnes prison in 94 province.

　　However, Booba, who was in prison, posted a tweet on the 21st, saying that he wanted to be a "beating bodyguard" like Benara. (Source: Twitter)

　　Another rapper, a cellmate of Kaaris, exposed a photo with Kaaris on Twitter, and arrogantly typed the coordinates of "Frena Prison" in the label, and then his mobile phone was found in the cell by the prison guards.

　　It is not uncommon for prisoners to hold mobile phones in prisons in France, but mobile phones that should have been banned are widely used by prisoners in prisons.

　　In 2017, more than 40,000 mobile phones, chargers and other related accessories were found in prisons across France, which was four times that of 2010. On the one hand, this is related to the surge in the number of prisoners. According to previous reports, the prison occupancy rate of Fresnes in the south of Paris is as high as 200%. Due to the lack of beds in the prison, some prisoners can only sleep on mattresses on the ground.

　　On the other hand, the way the mobile phone is transported into the prison also makes it impossible for prison guards to guard against it. According to reports, some people usually throw their mobile phones into the courtyard where prisoners walk from the outside; Another source said that sometimes mobile phones are difficult to be detected by machines. "Mobile phone accessories are getting smaller and smaller, and some of them contain very little metal, so that they can hardly be detected"; At the end of July this year, a prison guard in Nanterre was also charged and suspended for allegedly smuggling 10 mobile phones into the prison.

　　A senior official of the French Prison Administration (DAP) said, "We lost the ‘ The battle of mobile phones ’ " . However, in order to cope with this phenomenon, French Minister of Justice Nicole Belloubet said in January that it would spend 15 million euros (about 120 million yuan) to install mobile phone signal interference equipment, which currently has 804, but only 10% are in use; The department also plans to install 50,000 fixed telephones in the cells so as not to cut off the contact between prisoners and their relatives, and hopes to help prisoners reintegrate into society. (Overseas Network/Liang Yi)

The whole level of the double-row shack is divided into five levels: preface, blow to the head, dying, abyss, and power supply.

Click to view > > > Full chapter introduction for two people in a row < < <

1. Introduction of the shed chapter (portal: detailed explanation of the whole chapter of two-person trip)

Our story begins with a quarrel between a couple, who decided to divorce because they couldn’t accept each other, while their daughter in the house witnessed the whole process, holding two dolls in her hand, hoping that the two sides could get back together &hellip; &hellip;

2. Preface

Plot: While eating, parents told the girl that they were going to divorce. The little girl ran into the shed and found the title "Back of Love", hoping that her parents could get back together.

Step 3 hit the head

Plot: As soon as the camera turns, the husband and wife become dolls, and both sides are scared by this scene. Just when they are anxious, the book turns into an uncle with a beard, hoping to help them repair their broken feelings … Portal: the first customs clearance method for two people’s trip.

Step 4 be dying

Plot: After they came up, they met a vacuum cleaner damaged by Cody, and the angry vacuum cleaner blew them away. After falling to the lower floor, the book told them that if they want to see their daughter, they must climb the vacuum cleaner, so they started their adventure again … Portal: How to get through the checkpoint in pairs?

5. the abyss

Plot: After they escaped, they saw their daughter Ross, but the daughter couldn’t hear their voices, and the hammer next to them made a sound. It could help them, but they needed two people to help them rescue their friends in the toolbox, and then they got the hammer and nails …… The detailed strategy portal: How to get through the abyss of checkpoints when two people walked in a row.

Step 6 turn on the power

Plot: As a reward, the tools sent them to the daughter, but the daughter didn’t notice them. At this time, the annoying book came out again. It told them that if they wanted to see their daughter, they had to go to the upper window … Portal: How to connect the power through the checkpoint when two people walk.

What do you know about recyclables?

What is recyclable?

Recyclable materials are renewable resources, which refer to unpolluted, recyclable and recyclable wastes in domestic garbage, mainly including waste paper, waste plastics, waste metals, waste glass and waste fabrics.

Details of recyclables

01

Waste paper

Undisturbed paper products, such as cartons, cardboard, newspapers, books, paper, envelopes, advertising leaflets, express packaging boxes, etc.

Pay attention! Pay attention! When you want to throw away the packaging of beverage boxes and milk boxes and let them become garbage, be sure to rinse them clean.

02

Waste plastics

Plastic products without other impurities, such as beverage bottles, mineral water bottles, shampoo and bath bottles, edible oil drums, milk bottles, plastic bowls and basins, foam plastics, etc.

03

Scrap metal

Metal products whose whole or main body is metal, such as cans, metal packaging boxes (cans), pots, kettles, metal tableware, metal knives, metal racks, waste wires, etc.

04

Waste glass

Glass products without other impurities, such as seasoning bottles, wine bottles, vases, glass tableware, glasses, door and window glass, coffee table glass, glass handicrafts, etc.

05

Waste fabrics

Textile products that are not contaminated and have recycling channels, such as clothes, bags, bedding, curtains, etc.

Easily confused items

In life, some items are not recyclable, such as napkins, toilet paper and other water-soluble papers, wet wipes, plastic wrap, disposable paper cups, ultra-thin plastic bags, etc., which should be put into other trash cans.

In addition, some items that can be recycled by themselves should be put into other garbage after being polluted because they no longer have recycling value.

In order to reduce the difficulty of residents’ initial sorting, items that are not clear about whether they belong to recyclables can be put into other garbage first! This is also beneficial to the purity and recycling of recyclables.

Requirements for putting recyclable materials in.

The generated recyclables should be put into the blue recyclable bucket, or put into the intelligent recycling box, or contact the recycling personnel for home recycling. In the community with waste clothes recycling bins, residents can separate the waste clothes and put them in.

At the same time, residents should do:

1, when put should be put down gently;

2. Recyclable materials should be clean and dry to avoid pollution;

3. Waste paper should be as flat as possible, and cartons should be opened and flattened before being put into use;

4, three-dimensional packaging (all kinds of bottles, cans, boxes, etc.) before delivery, should empty the contents, try to clean, squashed after delivery;

5. Recyclable materials that are easily damaged or have sharp corners should be wrapped and put into use.

Cold knowledge of life: you can sell it for money.

Meat waste is recyclable waste.

Garbage classification creates beauty together.

HAN LU

Original title: "Garbage Classification? What do you know about recyclable garbage? 》

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