·▪•● فیلم های درخواستی مهندسی شیمی ●•▪·

سلام دوستان عزیز
این مجموعه از لینکهای دانلود فیلمهای آموزشی (how do they do it?) از شبکه دیسکوری خدمت شما عرض میکنم
این فیلمها شامل موضوعات مانند
(Recycling, Plasma TV, Fireworks, Railroad tracks, Ink ، Salt mines, Trainers, Ships, Watches, Wind farms، Tires, Excavators, Newspapers, Ports, Contact lenses) وغیره
این فیلمها با زبان انگلیسی ساده تهیه شده اند​

Discovery - 100 Greatest Discoveries - 3 of 9 - Chemistry
XviD | 4000 kbps | 1280x720 | 29.97 fps | AC3 | 45 min | RS | 1.36 GB​

Chemistry

1. Oxygen (1770s)
Joseph Priestley discovers oxygen; later, Antoine Lavoisier clarifies the nature of elements. Priestley produces oxygen in experiments and describes its role in combustion and respiration. Then, by dissolving fixed air in water, he invents carbonated water. Priestley, oblivious to the importance of his discovery, calls the new gas "dephlogisticated air." Lavoisier gives oxygen its name and correctly describes its role in combustion. Lavoisier then works with others to devise a chemical nomenclature, which serves as the basis of the modern system.

2. Atomic Theory (1808)
John Dalton provides a way of linking invisible atoms to measurable quantities like the volume of a gas or mass of a mineral. His atomic theory states that elements consist of tiny particles called atoms. Thus, a pure element consists of identical atoms, all with the same mass, and compounds consist of atoms of different elements combined together.

3. Atoms Combine Into Molecules (1811 onward)
Italian chemist Amedeo Avogadro finds that the atoms in elements combine to form molecules. Avogadro proposes that equal volumes of gases under equal conditions of temperature and pressure contain equal numbers of molecules.

4. Synthesis of Urea (1828)
Friedrich Woehler accidentally synthesizes urea from inorganic materials, proving that substances made by living things can be reproduced with nonliving substances. Until 1828, it was believed that organic substances could only form with the help of the "vital force" present in animals and plants.

5. Chemical Structure (1850s)
Friedrich Kekule figures out the chemical structure of benzene, bringing the study of molecular structure to the forefront of chemistry. He writes that after years of studying the nature of carbon-carbon bonds, he came up with the ring shape of the benzene molecule after dreaming of a snake seizing its own tail. The unusual structure solves the problem of how carbon atoms can bond with up to four other atoms at the same time.

6. Periodic Table of the Elements (1860s – 1870s)
Dmitry Mendeleyev realizes that if all of the 63 known elements are arranged in order of increasing atomic weight, their properties are repeated according to certain periodic cycles. He formulates the periodic table of the elements and predicts the existence of elements that have not yet been discovered. Three of those elements are found during his lifetime: gallium, scandium and germanium.

7. Electricity Transforms Chemicals (1807 – 1810)
Humphry Davy finds that electricity transforms chemicals. He uses an electric pile (an early battery) to separate salts by a process now known as electrolysis. With many batteries he is able to separate elemental potassium and sodium in calcium, strontium, barium and magnesium.

8. The Electron (1897)
J.J. Thomson discovers that the negatively charged particles emitted by cathode ray tubes are smaller than atoms and part of all atoms. He calls these particles, now known as electrons, "corpuscles."

9. Electrons for Chemical Bonds (1913 onward)
Niels Bohr publishes his model of atomic structure in which electrons travel in specific orbits around the nucleus, and the chemical properties of an element are largely determined by the number of electrons in its atoms' outer orbits. This paves the way to an understanding of how electrons are involved in chemical bonding.

10. Atoms Have Signatures of Light (1850s)
Gustav Kirchhoff and Robert Bunsen find that each element absorbs or emits light at specific wavelengths, producing specific spectra.

11. Radioactivity (1890s – 1900s)
Marie and Pierre Curie discover and isolate radioactive materials. After chemically extracting uranium from uranium ore, Marie notes the residual material is more "active" than the pure uranium. She concludes that the ore contains, in addition to uranium, new elements that are also radioactive. This leads to the discovery of the elements polonium and radium.

12. Plastics (1869 and 1900s)
John Wesley Hyatt formulates celluloid plastic for use as a substitute for ivory in the manufacture of billiard balls. Celluloid is the first important synthetic plastic and is used as a substitute for expensive substances such as ivory, amber, horn and tortoiseshell. Later, Leo Baekeland invents hardened plastics, specifically Bakelite, a synthetic substitute for the shellac used in electronic insulation.

13. Fullerenes (1985)
Robert Curl, Harold Kroto and Rick Smalley discover an entirely new class of carbon compound with a cage-like structure. This leads to the discovery of similar tube-like carbon structures. Collectively, the compounds come to be called buckminsterfullerenes, or fullerenes. The molecules are composed entirely of carbon and take the form of a hollow sphere, ellipsoid, tube or ring. Named for Richard Buckminster Fuller, the architect who created the geodesic dome, they are sometimes called "buckyballs" or "buckytubes." ”​

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فیلمی درباره تقطیر در خلا(Vacuum Distillation) با فرمت FLV
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Chemistry Comes Alive! Volume 5 covers a great number of topics in organic chemistry.

Manipulating and Transferring Samples

Heating and Cooling

Selecting a Heat Source
Gas Burner
Hot Plate
Reflux: Reactions at Constant Temperature
Preparing an Ice Bath
Mixing

Mechanical Mixing
Magnetic Stirrer
Manual Mixing
Mixing Safely
Transferring Samples

Obtaining a Liquid Sample
Pouring
Quantitative Transfer
2. Measuring

Electrical Properties

Conductivity Meter
Voltage of an Electrochemical Cell
Mass

Analytical Balance
Top-Loading Balance
Top-Loading Balance with Draft Shield
pH

pH Meter
pH Paper
Pressure

Barometer
McLeod Gauge Manometer
Recording Data

Chart Recorder
Reading a Scale
Spectroscopy

Spectroscope
Spectronic 20 Spectrophotometer
Single-Beam Recording Spectrophotometer
Double-Beam Recording Spectrophotometer
Diode-Array Spectrophotometer
Temperature

Thermometer
Calorimeter
Melting Point Apparatus
Titration

Titration Techniques and Concepts
A Complete Acid–Base Titration
Procedures and Mistakes
Volume

Precision of Measurement
Buret
Graduated Cylinder
Pipets
Volumetric Flask
3. Separating and Purifying

Centrifuge

Loading and Unloading a Centrifuge
Centrifuging a Sample
Removing Supernatant and Washing Precipitate
Chromatography

Paper Chromatography
Thin-Layer Chromatography
Gas Chromatography
Distillation

Simple Distillation
Distillation at Reduced Pressure
Using a Rotary Evaporator
Extraction

Separatory Funnel
Product Isolation
Filtration

Gravity Filtration
Vacuum Filtration
Recrystallization

Single-Solvent Method
Two-Solvent Method
4. Safety

Eye Protection
Handling and Mixing Chemicals
Handling Glassware
Heating and Hot Items
Loose Clothing, Hair, and Jewelry
Pipetting
Safe Lab Setting

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متاسفانه اطلاعاتم در این زمینه کامل نیست اما تا جایی که می دونم از مبدل dynamic scraped surface توی جاهایی استفاده می کنن که سیال خیلی رسوب زا هست و یا اینکه ویسکوزیته سیال خیلی بالا باشه و باعث بشه جریان لیمنار بوجود بیاد که اثر انتقال حرارت رو خیلی محدود می کنه، از این نوع مبدل استفاده می کنن، چون به علت حرکت اون شفت مرکزی، جلوی تشکیل رسوب یا هر ماده جامد دیگری رو بر روی سطح، میگیره. البته حرکت اون شفت مرکزی، مدل های مختلف داره، هم رفت و برگشتی، هم دورانی. اما در هر حال فقط برای جریان های مایع کاربرد داره.

اما مبدل screw، می تونه هم جریانهایی از مایع و هم جامد رو پروسس کنه.

درست گفتم ؟

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سلام
دقيقا درست گفتيد .و مرسي از اطلاعات خوبتون
مبدل هاي داراي اسكرپر عموما دولوله اي هستند و اسكرپر ميتونه هم داخل لوله و هم داخل لوله بيروني قرار بگيره كه وابسته به نوع سيال مي باشد . اين مبدلها از طريق 1. برداشتن لايه فولينگ 2. ايجاد تلاطم و ممانعت از تشكيل يخ و كريستال باعث افزايش انتقال حرارت مي شوند و عموما براي( سرد كردن) سيالات ويسكوز يا سيالاتي كه تشكيل كريستال داده و يا سيالات حساس به دما به كار ميرود.در صنايع داروسازي و شيميايي و پتروشيمي و غذايي كاربرد دارد . بر حسب قرار گيري و نوع تيغه ها عموما به سه دسته تقسيم مي شوند :
1.Rotating, tubular​