Create Ethereum wallet address

1. Ethereum is an open source public blockchain platform with smart contract function. As of February 2018, Ethernet is the second highest cryptocurrency in market value, second only to bitcoin. There are many ways to quickly create Ethereum wallet in daily coin collection. According to the operation, it can be completed quickly. After the creation, you can get free virtual coin directly from the website.

2. Ethereum wallet address is your bank card number. If you forget the address, you can use the private key, mnemonic words and keystore + password to import the wallet and retrieve it. Buying and selling Ethereum is even easier. You can open an account with $100 in the realm Kingdom, and then analyze the price. Buying up or down means buying in the right direction is profitable.

3. At present, Ethereum wallet specific development enterprises, such as fiwork mutual metal workshop, are more than one of the software system development enterprises using blockchain technology, and their development schemes are also more reference.

4. You're too easy to handle your wallet. I'll have a look at it right away.

5. This needs to be recharged, but we must pay attention to the risk. This chain is not particularly mainstream. It may be the capital disk or counterfeit currency.

6. Confinement is a thing that must be done after childbirth. If you don't take delivery, the maternal body will leave the root of the disease after pregnancy, which is difficult to cure. Pregnant women can choose to take delivery at home or in the delivery center

first of all, confinement is usually for one month. So whether at home or in the confinement center is the same, it needs to live for a month. But this time is not certain, can only be said to be at least a month's time to live. A month is a minimum time, even if the maternal recovery is fast, but also to live enough for a month. But if the maternal recovery is relatively slow, then it is not only to live for a month, it is necessary to live longer. Therefore, it is more recommended that pregnant women take delivery at home, which is more convenient and comfortable<

secondly, confinement is the key period for a newborn baby to recover. During this period, it is necessary to take good care of the baby. The time of each confinement is different, but it is generally 30 days or 42 days, so the body will recover more completely

in the end, the place to take delivery of the baby must choose a better place, a place with more complete facilities and better service. Otherwise, if the pregnant woman goes to the delivery center and no one is in charge, the delivery of the baby will be greatly reced

pay attention to diet after childbirth:

women have higher requirements for diet when they are in confinement, and many women think that there are not so many restrictions after childbirth, but as long as women are still in lactation, there are still many things to pay attention to

1. During lactation, women should not eat food with milk returning function, such as leek, malt, etc. Many women think ginseng tonic body is very effective, but ginseng will make maternal milk, in breast-feeding, it is best not to eat. In addition, more estrogen content of food is also easy to cause milk, such as pigeons, hens and so on

2. Women should not eat caffeinated food ring lactation. Caffeine can stimulate the nervous system. It is likely to enter the child's body through milk, causing damage to the child's nervous system and heart, and also causing indigestion

3. Eat less salt and monosodium glutamate, too much salt will increase the burden on the kidney. And monosodium glutamate will affect the development of children, eat too much monosodium glutamate will make children appear mental retardation, growth retardation and so on

women should not only pay attention to their diet when they are in confinement, even when they are out of confinement, as long as they are still in the lactation period, they can not do whatever they want in their diet, so as not to have adverse effects on their children.

7. The axial force is the inertial force.
for a gear group with a strip shape, the direction of the axial force is odd in the same direction (that is, 1.3 in the same direction) and even in the same direction
axial force is not divided into helical and straight teeth. It refers to the inertia of axial operation in a certain direction.

8.

Transaction

the behavior of blockchain transaction follows different rule sets

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e to the distributed and unlicensed nature of public blockchain, anyone can sign the transaction and broadcast it to the network

according to different blockchains, traders will be charged a certain transaction fee, which depends on the needs of users rather than the value of assets in the transaction

blockchain transactions do not require any central authority verification. It only needs to use the digital signature algorithm (DSA) corresponding to its blockchain to sign it with the private key

once a transaction is signed, broadcast to the network and mined into a successful block in the network, the transaction cannot be recovered

Ethereum transaction structure

Ethereum transaction data structure: transaction 0.1 eth

{
& 39; nonce':&# 39; 0x00', // Decimal: 0
& 39; gasLimit': &# 39; 0x5208', // Decimal system: 21000
& 39; gasPrice': &# 39; 0x3b9aca00', // Decimal system: 10000000000
& 39; to': &# 39;&# 39; ，// Sending address
& 39; value': &# 39; 0x16345785d8a0000',// 100000000000000000 ，10^17
' data': &# 39; 0x', // Decimal representation of null data; chainId': 1 / / blockchain network ID
}

these data have nothing to do with the transaction content, but have something to do with the execution mode of the transaction. This is because when you send a transaction in Ethereum, you must define some other parameters to tell miners how to handle your transaction. Transaction data structure has two attribute designs & quot; gas": & quot; gasPrice",& quot; gasLimit"

" gasPrice": The unit is Gwei, which is 1 / 1000 eth, indicating the transaction cost

& quot; gasLimit": The maximum gas charge allowed for the transaction

these two values are usually filled in automatically by the wallet provider

in addition, you need to specify which Ethereum network to execute the transaction (chainid): 1 represents the Ethereum main network

ring development, tests are usually carried out locally and on the test network, and transactions are carried out through the test eth issued by the test network to avoid economic losses. After the test, enter the main network transaction

in addition, if you need to submit some other data, you can use & quot; data" And & quot; nonce" Attach as part of a transaction

a nonce (number used only once) is the value used by Ethereum to track transactions, which helps to avoid double spending and replay attacks in the network

Ethereum transaction signature

Ethereum transaction involves ECDSA algorithm. Taking JavaScript code as an example, the popular ethers.js is used to call ECDSA algorithm for transaction signature

const ethers = require(' ethers')

const signer = new ethers.Wallet(' Wallet address

signer.signTransaction({

' nonce':&# 39; 0x00', // Decimal: 0

& 39; gasLimit': &# 39; 0x5208', // Decimal: 21000

& 39; gasPrice': &# 39; 0x3b9aca00', // Decimal 10000000000

& 39; to': &# 39;&# 39; ，// Sending address

& 39; value': &# 39; 0x16345785d8a0000',// 100000000000000000 ，10^17

' data': &# 39; 0x', // Decimal representation of null data

& 39; chainId': 1 / / blockchain network ID

})

. Then (console. Log)

you can use the online application composer to deliver signed transactions to Ethereum. This is known as "offline signature.". Offline signatures are particularly useful for applications such as status channels, which are smart contracts that track the balance between two accounts and transfer funds after a signed transaction is submitted. Offline signature is also a common practice in dexes

you can also use online wallet to create signature verification and broadcast through Ethereum account

with Portis, you can sign a transaction to interact with the gas station network (GSN)

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