20xx英文報告格式(編輯修改稿)
2025-01-12 06:43 本頁面
【文章內(nèi)容簡介】 re between 600 and 800 words in report on robinson crusoe gone with the wind篇四：英文讀書報告撰寫格式 英文讀書報告撰寫格式
1．字體均為times new roman報告題目為3號黑體居中
學生姓名、專業(yè)班級、學號、正文及參考文獻均為小4號 雙倍行距
2．打印紙張規(guī)格：用a4紙單面打印。
3．報告第一頁第一行應(yīng)為：報告題目 第二行靠右應(yīng)為：學生姓名、專業(yè)班級、學號接下來是正文；參考文獻在正文之后。
4. 報告字數(shù)為10001500字。
篇二：英文實驗報告模板
Determination of heavy metals in soil byatomic absorption spectrometry(AAS)
Name: XuFei Group: The 3rd group
Date: Sep. 20th 2020
Part 1 The introduction
purposes
(1)Learn how to operate the atomic absorption spectrometry。
(2)Learn how to do the pretreatment of soil samples。
(3)Get familiar with the application of atomic absorption spectrometry.
principles
Atomic Absorption Spectrometry (AAS) is a technique for measuring quantities of chemical elements present in environmental samples by measuring the absorbed radiation by the chemical element of interest. This is done by reading the spectra produced when the sample is excited by radiation. The atoms absorb ultraviolet or visible light and make transitions to higher energy levels .
Atomic absorption methods measure the amount of energy in the form of photons of light that are absorbed by the sample. A detector measures the wavelengths of light transmitted by the sample, and pares them to the wavelengths which originally passed through the sample. A signal processor then integrates the changes in wavelength absorbed, which appear in the readout as peaks of energy absorption at discrete wavelengths. The energy required for an electron to leave an atom is known as ionization energy and is specific to each chemical element. When an electron moves from one energy level to another within the atom, a photon is emitted with energy E. Atoms of an element emit a characteristic spectral line. Every atom has its own distinct pattern of wavelengths at which it will absorb energy, due to the unique configuration of electrons in its outer shell. This enables the qualitative analysis of a sample.
The concentration is calculated based on the BeerLambert law. Absorbance is directly proportional to the concentration of the analyte absorbed for the existing set of conditions. The concentration is usually determined from a calibration curve, obtained using standards of known concentration. Calibration Curve Method: Prepare standard solutions of at least three different concentrations, measure the absorbance of these standard solutions, and prepare a calibration curve from the values obtained. Then measure the absorbance of the test solution adjusted in concentration to a measurable range, and determine the concentration of the element from the calibration curve.
Part 2 The materials and apparatus
Atomic absorption spectrometry。 Cu hollow cathode lamp。 AC voltage stabilizer。 oilfree gas pressor。 acetylene cylinder。 oscillator。 sample boat。 Erlenmeyer flask with stopper (100 ml)。 beaker。 graduate cylinder。 pipette.
Part 3 The procedure
operating procedure for AAS
(1) inspect major ponents to ensure operating normal.
(2) Install required hollow cathode lamp. Select “T” before turning to the power and hollow cathode lamp. Then select appropriate la mp current and preheat for 30min.
(3) Make sure electrical meter to point to zero and then turn on highvoltage power.
(4) Sele
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