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Topics - Tanvir Ahmed Chowdhury

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46
Textile Engineering / Properties of soaps
« on: January 12, 2017, 03:01:31 PM »
1.    Soap dissolves very slowly in cold water but rapidly in hot water.

2. Soap dissolves in hot alcohol but is only carefully soluble in other organic solvents such as acetone, ether or petroleum.

3. In extremely dilute solutions soap ionizes as

      RCOONa ↔ RCOO‾+ Na+
                                             RCOO‾+ H2O ↔ RCOOH + OH‾   

4. Sometimes there are free fatty acid molecules in soap to form what is known as acid soaps. 
 


5. Soap reacts with hard water to form insoluble soap.
                                   

6. The no. of carbon atoms in the aliphatic chain of soap is very important.
      Less than 9(C) – No detergency power
      9-17(C) – Extremely good detergent
      Above 17(C) – Poor solubility

47
Textile Engineering / Soaps
« on: January 12, 2017, 03:01:03 PM »
Soaps are sodium or potassium salts of higher fatty acids (are organic acids that have more than 16 carbon atoms in their molecules) like stearic, palmitic and oleic acids. Soap is a metallic salt of saturated (CnH2n+1COOH) or unsaturated (CnH2n-1COOH) higher fatty acid. There may be Pb, Mg, Ca or other metallic salts. The sodium soaps are called hard soaps and the potassium soaps are known as soft soaps. Soaps are obtained from oils and fats. For example, tri-stearin is got from beef and mutton tallow, tri-palmitin from palm oil and tri-olein from lard (pig fat), olive oil and cotton seed oil.


48
Textile Engineering / Standard or Quality of Dye-house water
« on: January 12, 2017, 03:00:21 PM »
   Water must be colorless and odorless
   pH of water should be ±7
   Hardness of water must be less than 5 degree in german hardness scale
   Amount of dissolved solids in water should be less than 1 mg/liter
   Amount of solid deposits in water should be less than 50 mg/liter
   Amount of organic substances in water should be less than 20 mg/liter
   Amount of inorganic salts in water should be less than 500 mg/liter
   Iron content in water should be less than 0.1 mg/litre
   Copper content in water should be less than 0.005 mg/litre
   Nitrate content in water should be less than 50 mg/litre
   Nitrite content in water should be less than 5 mg/litre

49
Textile Engineering / Types of Water Hardness
« on: January 12, 2017, 02:59:53 PM »
0 Temporary Hardness:

The presence of bi-carbonate salts of calcium, magnesium and iron makes the water temporary hard. Temporary hardness of water can be removed easily by simply boiling the water. When the water is boiled, the bi-carbonates decompose with the liberation of CO2 and insoluble carbonates deposits as precipitation under water.

          Ca (HCO3)2 → CaCO3 ↓ + CO2 + H2O

0 Permanent Hardness: 

Permanent hardness arises when water contains soluble salts of calcium and magnesium such as their sulphates and chlorides. Permanent hardness is hardness (mineral content) that cannot be removed by boiling.  Permanent hardness can be removed by converting the sulphate salts into carbonates with the help of soda ash (Na2CO3).

   CaSO4 + Na2CO3 → Na2SO4 + CaCO3

Permanent hardness can also be removed with using a water softener or ion exchange column, where the calcium and magnesium ions are exchanged with the sodium ions in the column.

50
Textile Engineering / Water hardness
« on: January 12, 2017, 02:59:31 PM »
Hardness in water is defined as the presence of multivalent cations. In other words, hardness is defined as the presence of soluble calcium and magnesium salts in the water. The presence of sulpahates, chlorides, carbonates and bi-carbonates of calcium, magnesium and ferrous salts make water hard. Due to water hardness, soaps and detergents can not creat foam easily. Rather they react with hardness creating metals and form insoluble organic salts.

For example, sodium stearate reacts with calcium as follows-
   
CaSO4+2RCOONa→ (RCOO)2Ca ↓ + Na2SO4
MgSO4+2RCOONa→ (RCOO)2Mg ↓ + Na2SO4

51
Water is used extensively throughout textile processing operations. a plentiful supply of suitable water is essential for a wet processing industry. Water is considered as the life line of the wet processing industry as because it is the single most used chemical and is also universal cleansing agent. The amount of water used varies widely in the industry, depending on specific processes operated in the mill, equipment used, and existing management philosophy concerning water used. Water is used in the plant in –

0   In Boiler for supplying steam for heating and drying
           0 In different types of wet processes-
   In Sizing
   In Desizing
   In Scouring
   In Bleaching
   In Mercerizing
   In Dyeing
   In Printing
   In Finishing
   In Rinsing and Washing

52
Textile Engineering / Kinds of Managers
« on: January 12, 2017, 02:57:33 PM »
 Managers can be differentiated according to their level in the organization. The most common view considers three basic levels: top, middle and first line managers.

I)   Top Managers: who is working in the top position and try to manage the overall organization. Example- President, Vice-President, Chief Executive Officers (CEO) etc.
Responsible task: goals setting, over all strategy and operating policies.
                        II)      Middle Managers: the largest group of managers in the most   organization. Common middle-management tittles include Plant manager, Operations managers and Division head.
                                       Responsible task: implementing the policies and plans developed by top managers and for supervising and coordinating the activities of lower-level managers.
III)   First-line Managers: They supervise and coordinate the activities of operating employees. Common titles for line managers are- Supervisor, Coordinator and Office Manager.
          Responsible for: looking after the operating employees and implemented the plans developed by middle managers.

53
Textile Engineering / Manager
« on: January 12, 2017, 02:57:08 PM »
A manager is a person who is responsible for directing the efforts aimed at helping organizations achieve their goals with the best use of resources. C.S. George Says-‘a manager is who accomplishes objectives by directing the efforts of others.
In today's world managers are the most basic resource of any business enterprise. Managers are also the most expensive resource of a business. Modern society's aims and aspirations call for unprecedented co-operative effort. Our capacity to rebuild slums, to eliminate pollution, to give people an opportunity for self expression; to raise the standard of living and to achieve many other social and personal objectives depends on joint or co-operative activity.
The job of managers and management is to make such co-operative efforts function properly. Managers are required to convert disorganized resources of men, machines, materials and money in to a useful and productive enterprise. Managers conceive of the service, an organization can render, mobilize the required means of production, co-ordinate activities within and outside the organization; and above all, inspires people associated with the organization to work towards agreed common objectives. Managers therefore, are the driving or activating element of an organization.

54
Textile Engineering / Functions of Management
« on: January 12, 2017, 02:56:37 PM »
Planning, Organizing, Staffing, Directing and Controlling.

55
Textile Engineering / Why Is Management Important?
« on: January 12, 2017, 02:55:56 PM »
All organizations rely upon group efforts to achieve goals.  And whenever two or more people are required to work together, management is necessary.  According to the U.S. Bureau of Labor Statistics, management positions are projected to continue to grow by an average of 7% percent.  If that is not enough reason to become a believer in management, maybe the reasons below will:
•   Accomplish goals – It is possible to accomplish goals without management, but it would be extremely difficult.  With proper management, an organization is allowed to plan and balance their resources in such a way that every task is completed.  This does not only relate to businesses, but it also applies to our lives.
•   Be more efficient – There are only so many hours in a work day, so it beneficial to make the most of it.  The last thing a company wants its employees to do is to waste time.  With good time management skills, companies are able to get as much work done as possible with the time given to them.
•   Make better decisions – The choices a business makes can make the difference between being successful to being a complete disaster.  Therefore, making rational decisions is vital for a company if they want to do well. With good time management, they will have more time to weigh out the positives from the negatives in their decision making.
•   Earn more profit – When all of the other benefits mentioned above are met, it will usually equal to an increase of profit for the company.  The most successful and profitable businesses in the world attribute a lot of it to their management skills

56
Common Forum/Request/Suggestions / Factors of Terrorism
« on: January 12, 2017, 02:50:08 PM »
some of major factors are given under:
1. Extreme Poverty
2. Unequal Distribution of Resources
3. Economic Exploitation
4. Over-Population
5. Illiteracy
6. Unemployment
7. Extremism & Sectarianism
8. Imbalance Opportunity Structure
9. Weak Social Bonds
10. Political Instability
11. Deprivation of Fundamental Rights
12. Institutional Evasions
13. Anathema of Social Injustice
14. Visceral Political Dispensation
15. Social Imbalance & Regional Disparities
16. Proliferation of Weapon of Mass Destruction
17. Impact of Proxy War of Afghanistan (1979-1989)
18. Policies against Islamic Revolution of Iran (1979)
19. Political Insurgency

57
Constructivism thinks that the international order is contingent upon how states perceive one another.  What is important is if states perceive one another as threats or as potential allies.  This determines how peaceful the international system can be. Constructivist theory has, unlike Realism and Liberalism, people at the heart of its definition of power and takes into account that people make up the states and institutions that work within the anarchy of the world. Constructivists view individual people and the ideas that they believe in are what gives these things meaning. They argue that power does not reside in the state or institutions, but rather in ideas that people use and collectively come to believe in.

58
Liberalism sees a much less anarchic world order.  It believes that international bodies like the UN can create an international system that is based more on cooperation than on competition.  More international bodies leads to a greater chance for peace. Liberal theory too, believes in the view that states are seeking military power to combat anarchy. However, it views the players involved in different terms than Realists and offers a different solution to the problem of war. For Liberal theory, there is hope for world peace if states seek common ground, forming alliances and institutions for policing the world powers.

59
Realism conceives of the international system as anarchy.  It believes that states must therefore always act in ways that will get them the most power.  In such a belief system, organizations like the United Nations are pointless because states will only do things that will increase their power. Realist theory holds that events in the world follow one basic system; a Hobbesian system where everyone must be viewed as a threat and the only way to survive is to gain more power than your rivals. Because there is anarchy in the international world, Realists believe that greater power is the only way for states to secure their sovereignty, and this leads to the belief that states are the main players in international politics because the system discourages individuality in favor of these types of power struggles.

60
How can we implementation of IE in all kind of Textile Industries. Please explain..................

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